Administrative Appointments


  • Executive Committee, Stanford Cardiovascular Institute (2010 - Present)
  • Member, Stanford Diabetes Research Center (2018 - Present)
  • Co-Director, Cardiovascular Pulmonary Sciences Application (2005 - 2018)

Honors & Awards


  • Department of Medicine Teaching Award, Stanford (2003)
  • Fellow, Arteriosclerosis, Thrombosis, and Vascular Biology Council of the American Heart Association (2003)
  • Established Investigator Award, American Heart Association (2008)

Professional Education


  • PhD, Thomas Jefferson University, Cardiovascular Physiology (1991)

Current Research and Scholarly Interests


Our primary interests are in understanding the molecular underpinnings of vascular disease as well as assessing disease risk. We use a wide range of biochemical, molecular and physiological techniques to make primary observations in cell systems as well as preclinical models. Furthermore, we continue to extend our findings to human subjects in order to confirm their clinical applicability. Current research projects include:

Mechanisms regulating atherosclerosis and abdominal aortic aneurysm disease: While single genes can have dramatic effects in cellular biology, it is becoming increasingly clear that vascular disease (and health) is regulated by the coordinated expression of gene cassettes or pathways. By monitoring expression patterns of the entire genome simultaneously, we can begin to identify networks of genes that work in concert to affect disease progression. Moreover, this approach can often implicate specific nexus genes that are at the center of larger networks and/or participate in multiple pathways. Additionally, we are investigating the role microRNAs, a newly discovered class of small RNA molecues, in orchestrating the activity of multiple genes during the course of disease.

Role of insulin resistance: Reduced activity of the endogenous hormone, insulin, is now recognized as a cardinal feature of type 2 diabetes and an independent risk factor for cardiovascular disease. We have investigated the effects of insulin resistance in several tissues and have recently focused our attention on adipose tissue biology and how it relates to CVD. Long known as a storage vehicle for excess calories, the fat cell is now recognized to be a factory of different products that can not only affect local activity, but can circulate in the blood as hormones and regulate many biological processes. For example, we have recently reported that the novel hormone, apelin, is produced by fat tissue and has important effects upon insulin resistance, obesity and diabetes, all of which have significant implications for cardiovascular disease.

Biomarkers for risk assessment: In addition to target identification, we are applying transcriptional profiling and pathway analysis for another important aspect of cardiovascular disease management--biomarker discovery. As the name connotes, a biomarker should be a good indication of the disease state and thereby allow for early detection as well as monitoring disease progression and, hopefully, efficacy of an applied therapy. Biomarkers can encompass a wide range of molecules including DNA variants, RNA, proteins, as well as lipids. They can even encompass modalities such as molecular imaging. We are engaged in not only identifying novel biomarkers for cardiovascular disease, but also in producing algorithms that combine multiple biomarkers to optimally assess risk.

Clinical Trials


  • Effects of Dietary Antioxidants on Cardiovascular Risk Factors Not Recruiting

    The aim of the Antioxidant Study was to compare the efficacy of foods naturally rich in antioxidants with that of antioxidants in a pill form on markers of inflammation and plasma cholesterol in healthy adults at risk of cardiovascular disease.

    Stanford is currently not accepting patients for this trial. For more information, please contact Antonella Dewell, (650) 736 - 8577.

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  • Effects of Glutathione (an Antioxidant) and N-Acetylcysteine on Inflammation Not Recruiting

    The rationale for the potential role of antioxidants in the prevention of cardiovascular diseases (CVD) remains strong despite the disappointing results of recent trials with a few select antioxidant vitamins. Glutathione (GSH) is one of the body's most powerful antioxidant agents but there is a surprising paucity of data on its use as an interventional therapy. Glutathione, when taken orally, is immediately broken down into its constituent amino acids, of which cysteine is the only one to be essential. Available cysteine is the critical determinant of intracellular GSH concentrations. N-acetyl cysteine (NAC) is an antioxidant supplement that has been used to provide a source of cysteine to replete GSH levels. By replenishing endogenous glutathione, it is possible that NAC would exert the same effect(s) as exogenous GSH. However, there is a new delivery system, liposomal GSH, which keeps glutathione intact. In this study, the investigators propose to match the cysteine content of NAC and GSH and compare the effects of these two supplements, at two different doses, on markers of inflammation and oxidative stress.

    Stanford is currently not accepting patients for this trial. For more information, please contact Antonella Dewell, (650) 736 - 8577.

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  • Effects of Omega-3 Fatty Acids on Markers of Inflammation Not Recruiting

    The major purpose of this study is to examine the effect of two sources of dietary omega-3 fatty acids, each given at two doses, on potential health benefits related to cardiovascular disease prevention. The two sources of dietary omega-3 fatty acids will be fish oil, and flaxseed oil.

    Stanford is currently not accepting patients for this trial. For more information, please contact Antonella Dewell, (650) 736 - 8577.

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  • Exercise Therapy to Treat Adults With Abdominal Aortic Aneurysms Not Recruiting

    An abdominal aortic aneurysm (AAA) is a weakened and enlarged area in the abdominal aorta, which is a large blood vessel in the abdomen. If an AAA ruptures, it can be life-threatening. Research has shown that sedentary individuals are at increased risk of developing AAAs. This study will evaluate the effectiveness of an exercise program at limiting the growth of small AAAs in older individuals.

    Stanford is currently not accepting patients for this trial. For more information, please contact Ronald Dalman, (650) 723 - 2169.

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  • Permission to Collect Blood Over Time for Research Not Recruiting

    To determine whether biomarkers assessed in blood samples can be used to detect individuals at risk for developing blood clots or worsening of their underlying disease. The ultimate goal of the study is to identify key biomarkers derived from blood that are most characteristic and informative of individuals who will go on to develop a clotting complication.

    Stanford is currently not accepting patients for this trial. For more information, please contact Fizaa Ahmed, 650-725-6409.

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2023-24 Courses


Stanford Advisees


Graduate and Fellowship Programs


All Publications


  • Genome-wide association meta-analysis identifies risk loci for abdominal aortic aneurysm and highlights PCSK9 as a therapeutic target NATURE GENETICS Roychowdhury, T., Klarin, D., Levin, M. G., Spin, J. M., Rhee, Y., Deng, A., Headley, C. A., Tsao, N. L., Gellatly, C., Zuber, V., Shen, F., Hornsby, W. E., Laursen, I., Verma, S. S., Locke, A. E., Einarsson, G., Thorleifsson, G., Graham, S. E., Dikilitas, O., Pattee, J. W., Judy, R. L., Pauls-Verges, F., Nielsen, J. B., Wolford, B. N., Brumpton, B. M., Dilme, J., Peypoch, O., Juscafresa, L., Edwards, T. L., Li, D., Banasik, K., Brunak, S., Jacobsen, R. L., Garcia-Barrio, M. T., Zhang, J., Rasmussen, L. M., Lee, R., Handa, A., Wanhainen, A., Mani, K., Lindholt, J. S., Obel, L. M., Strauss, E., Oszkinis, G., Nelson, C. P., Saxby, K. L., van Herwaarden, J. A., van der Laan, S. W., van Setten, J., Camacho, M., Davis, F. M., Wasikowski, R., Tsoi, L. C., Gudjonsson, J. E., Eliason, J. L., Coleman, D. M., Henke, P. K., Ganesh, S. K., Chen, Y., Guan, W., Pankow, J. S., Pankratz, N., Pedersen, O. B., Erikstrup, C., Tang, W., Hveem, K., Gudbjartsson, D., Gretarsdottir, S., Thorsteinsdottir, U., Holm, H., Stefansson, K., Ferreira, M. A., Baras, A., Kullo, I. J., Ritchie, M. D., Christensen, A. H., Iversen, K. K., Eldrup, N., Sillesen, H., Ostrowski, S. R., Bundgaard, H., Ullum, H., Burgess, S., Gill, D., Gallagher, K., Sabater-Lleal, M., Surakka, I., Jones, G. T., Bown, M. J., Tsao, P. S., Willer, C. J., Damrauer, S. M., Dudbridge, F., Samani, N. J., DiscovEHR, Regeneron Genetics Ctr, UK Aneurysm Growth Study, DBDS Genomic Consortium, VA Million Vet Program 2023
  • Genome-wide association meta-analysis identifies risk loci for abdominal aortic aneurysm and highlights PCSK9 as a therapeutic target. Nature genetics Roychowdhury, T., Klarin, D., Levin, M. G., Spin, J. M., Rhee, Y. H., Deng, A., Headley, C. A., Tsao, N. L., Gellatly, C., Zuber, V., Shen, F., Hornsby, W. E., Laursen, I. H., Verma, S. S., Locke, A. E., Einarsson, G., Thorleifsson, G., Graham, S. E., Dikilitas, O., Pattee, J. W., Judy, R. L., Pauls-Verges, F., Nielsen, J. B., Wolford, B. N., Brumpton, B. M., Dilmé, J., Peypoch, O., Juscafresa, L. C., Edwards, T. L., Li, D., Banasik, K., Brunak, S., Jacobsen, R. L., Garcia-Barrio, M. T., Zhang, J., Rasmussen, L. M., Lee, R., Handa, A., Wanhainen, A., Mani, K., Lindholt, J. S., Obel, L. M., Strauss, E., Oszkinis, G., Nelson, C. P., Saxby, K. L., van Herwaarden, J. A., van der Laan, S. W., van Setten, J., Camacho, M., Davis, F. M., Wasikowski, R., Tsoi, L. C., Gudjonsson, J. E., Eliason, J. L., Coleman, D. M., Henke, P. K., Ganesh, S. K., Chen, Y. E., Guan, W., Pankow, J. S., Pankratz, N., Pedersen, O. B., Erikstrup, C., Tang, W., Hveem, K., Gudbjartsson, D., Gretarsdottir, S., Thorsteinsdottir, U., Holm, H., Stefansson, K., Ferreira, M. A., Baras, A., Kullo, I. J., Ritchie, M. D., Christensen, A. H., Iversen, K. K., Eldrup, N., Sillesen, H., Ostrowski, S. R., Bundgaard, H., Ullum, H., Burgess, S., Gill, D., Gallagher, K., Sabater-Lleal, M., Surakka, I., Jones, G. T., Bown, M. J., Tsao, P. S., Willer, C. J., Damrauer, S. M. 2023

    Abstract

    Abdominal aortic aneurysm (AAA) is a common disease with substantial heritability. In this study, we performed a genome-wide association meta-analysis from 14 discovery cohorts and uncovered 141 independent associations, including 97 previously unreported loci. A polygenic risk score derived from meta-analysis explained AAA risk beyond clinical risk factors. Genes at AAA risk loci indicate involvement of lipid metabolism, vascular development and remodeling, extracellular matrix dysregulation and inflammation as key mechanisms in AAA pathogenesis. These genes also indicate overlap between the development of AAA and other monogenic aortopathies, particularly via transforming growth factor β signaling. Motivated by the strong evidence for the role of lipid metabolism in AAA, we used Mendelian randomization to establish the central role of nonhigh-density lipoprotein cholesterol in AAA and identified the opportunity for repurposing of proprotein convertase, subtilisin/kexin-type 9 (PCSK9) inhibitors. This was supported by a study demonstrating that PCSK9 loss of function prevented the development of AAA in a preclinical mouse model.

    View details for DOI 10.1038/s41588-023-01510-y

    View details for PubMedID 37845353

    View details for PubMedCentralID 5800308

  • E-cigarette exposure augments murine abdominal aortic aneurysm development: role of Chil1. Cardiovascular research Mulorz, J., Spin, J. M., Mulorz, P., Wagenhauser, M., Deng, A., Mattern, K., Rhee, Y. H., Toyama, K., Adam, M., Schelzig, H., Maegdefessel, L., Tsao, P. S. 2022

    Abstract

    AIMS: Abdominal aortic aneurysm (AAA) is a common cardiovascular disease with a strong correlation to smoking, although underlying mechanisms have been minimally explored. Electronic cigarettes (e-cigs) have gained recent broad popularity and can deliver nicotine at comparable levels to tobacco cigarettes, but effects on AAA development are unknown.METHODS AND RESULTS: We evaluated the impact of daily e-cig vaping with nicotine on AAA using two complementary murine models and found that exposure enhanced aneurysm development in both models and genders. E-cigs induced changes in key mediators of AAA development including cytokine chitinase-3-like protein 1 (CHI3L1/Chil1) and its targeting microRNA-24 (miR-24). We show that nicotine triggers inflammatory signaling and reactive oxygen species while modulating miR-24 and CHI3L1/Chil1 in vitro, and that Chil1 is crucial to e-cig-augmented aneurysm formation using a knockout model.CONCLUSIONS: In conclusion our work shows increased aneurysm formation along with augmented vascular inflammation in response to e-cig exposure with nicotine. Further we identify Chil1 as a key mediator in this context. Our data raise concerns regarding the potentially harmful long-term effects of e-cig nicotine vaping.TRANSLATIONAL PERSPECTIVE: Smoking is one of the most hazardous modifiable risk factors, with clear links to abdominal aortic aneurysm. E-cig vaping has displayed explosive growth in popularity. Intended for smoking cessation, it has been taken up by millions with no such clinical need, delivering nicotine addiction to new generations. The presumption that vaping is safer than tobacco overlooks the potential cardiovascular risks of nicotine. This study shows for the first time that inhaled e-cig nicotine vapor augments experimental AAA and aortic inflammation, suggests a mechanistic role for the cytokine Chil1/CHI3L1 and its regulator microRNA-24, and raises red flags regarding longitudinal e-cig safety.

    View details for DOI 10.1093/cvr/cvac173

    View details for PubMedID 36413508

  • The power of genetic diversity in genome-wide association studies of lipids. Nature Graham, S. E., Clarke, S. L., Wu, K. H., Kanoni, S., Zajac, G. J., Ramdas, S., Surakka, I., Ntalla, I., Vedantam, S., Winkler, T. W., Locke, A. E., Marouli, E., Hwang, M. Y., Han, S., Narita, A., Choudhury, A., Bentley, A. R., Ekoru, K., Verma, A., Trivedi, B., Martin, H. C., Hunt, K. A., Hui, Q., Klarin, D., Zhu, X., Thorleifsson, G., Helgadottir, A., Gudbjartsson, D. F., Holm, H., Olafsson, I., Akiyama, M., Sakaue, S., Terao, C., Kanai, M., Zhou, W., Brumpton, B. M., Rasheed, H., Ruotsalainen, S. E., Havulinna, A. S., Veturi, Y., Feng, Q., Rosenthal, E. A., Lingren, T., Pacheco, J. A., Pendergrass, S. A., Haessler, J., Giulianini, F., Bradford, Y., Miller, J. E., Campbell, A., Lin, K., Millwood, I. Y., Hindy, G., Rasheed, A., Faul, J. D., Zhao, W., Weir, D. R., Turman, C., Huang, H., Graff, M., Mahajan, A., Brown, M. R., Zhang, W., Yu, K., Schmidt, E. M., Pandit, A., Gustafsson, S., Yin, X., Luan, J., Zhao, J., Matsuda, F., Jang, H., Yoon, K., Medina-Gomez, C., Pitsillides, A., Hottenga, J. J., Willemsen, G., Wood, A. R., Ji, Y., Gao, Z., Haworth, S., Mitchell, R. E., Chai, J. F., Aadahl, M., Yao, J., Manichaikul, A., Warren, H. R., Ramirez, J., Bork-Jensen, J., Karhus, L. L., Goel, A., Sabater-Lleal, M., Noordam, R., Sidore, C., Fiorillo, E., McDaid, A. F., Marques-Vidal, P., Wielscher, M., Trompet, S., Sattar, N., Mollehave, L. T., Thuesen, B. H., Munz, M., Zeng, L., Huang, J., Yang, B., Poveda, A., Kurbasic, A., Lamina, C., Forer, L., Scholz, M., Galesloot, T. E., Bradfield, J. P., Daw, E. W., Zmuda, J. M., Mitchell, J. S., Fuchsberger, C., Christensen, H., Brody, J. A., Feitosa, M. F., Wojczynski, M. K., Preuss, M., Mangino, M., Christofidou, P., Verweij, N., Benjamins, J. W., Engmann, J., Kember, R. L., Slieker, R. C., Lo, K. S., Zilhao, N. R., Le, P., Kleber, M. E., Delgado, G. E., Huo, S., Ikeda, D. D., Iha, H., Yang, J., Liu, J., Leonard, H. L., Marten, J., Schmidt, B., Arendt, M., Smyth, L. J., Canadas-Garre, M., Wang, C., Nakatochi, M., Wong, A., Hutri-Kahonen, N., Sim, X., Xia, R., Huerta-Chagoya, A., Fernandez-Lopez, J. C., Lyssenko, V., Ahmed, M., Jackson, A. U., Irvin, M. R., Oldmeadow, C., Kim, H., Ryu, S., Timmers, P. R., Arbeeva, L., Dorajoo, R., Lange, L. A., Chai, X., Prasad, G., Lores-Motta, L., Pauper, M., Long, J., Li, X., Theusch, E., Takeuchi, F., Spracklen, C. N., Loukola, A., Bollepalli, S., Warner, S. C., Wang, Y. X., Wei, W. B., Nutile, T., Ruggiero, D., Sung, Y. J., Hung, Y., Chen, S., Liu, F., Yang, J., Kentistou, K. A., Gorski, M., Brumat, M., Meidtner, K., Bielak, L. F., Smith, J. A., Hebbar, P., Farmaki, A., Hofer, E., Lin, M., Xue, C., Zhang, J., Concas, M. P., Vaccargiu, S., van der Most, P. J., Pitkanen, N., Cade, B. E., Lee, J., van der Laan, S. W., Chitrala, K. N., Weiss, S., Zimmermann, M. E., Lee, J. Y., Choi, H. S., Nethander, M., Freitag-Wolf, S., Southam, L., Rayner, N. W., Wang, C. A., Lin, S., Wang, J., Couture, C., Lyytikainen, L., Nikus, K., Cuellar-Partida, G., Vestergaard, H., Hildalgo, B., Giannakopoulou, O., Cai, Q., Obura, M. O., van Setten, J., Li, X., Schwander, K., Terzikhan, N., Shin, J. H., Jackson, R. D., Reiner, A. P., Martin, L. W., Chen, Z., Li, L., Highland, H. M., Young, K. L., Kawaguchi, T., Thiery, J., Bis, J. C., Nadkarni, G. N., Launer, L. J., Li, H., Nalls, M. A., Raitakari, O. T., Ichihara, S., Wild, S. H., Nelson, C. P., Campbell, H., Jager, S., Nabika, T., Al-Mulla, F., Niinikoski, H., Braund, P. S., Kolcic, I., Kovacs, P., Giardoglou, T., Katsuya, T., Bhatti, K. F., de Kleijn, D., de Borst, G. J., Kim, E. K., Adams, H. H., Ikram, M. A., Zhu, X., Asselbergs, F. W., Kraaijeveld, A. O., Beulens, J. W., Shu, X., Rallidis, L. S., Pedersen, O., Hansen, T., Mitchell, P., Hewitt, A. W., Kahonen, M., Perusse, L., Bouchard, C., Tonjes, A., Chen, Y. I., Pennell, C. E., Mori, T. A., Lieb, W., Franke, A., Ohlsson, C., Mellstrom, D., Cho, Y. S., Lee, H., Yuan, J., Koh, W., Rhee, S. Y., Woo, J., Heid, I. M., Stark, K. J., Volzke, H., Homuth, G., Evans, M. K., Zonderman, A. B., Polasek, O., Pasterkamp, G., Hoefer, I. E., Redline, S., Pahkala, K., Oldehinkel, A. J., Snieder, H., Biino, G., Schmidt, R., Schmidt, H., Chen, Y. E., Bandinelli, S., Dedoussis, G., Thanaraj, T. A., Kardia, S. L., Kato, N., Schulze, M. B., Girotto, G., Jung, B., Boger, C. A., Joshi, P. K., Bennett, D. A., De Jager, P. L., Lu, X., Mamakou, V., Brown, M., Caulfield, M. J., Munroe, P. B., Guo, X., Ciullo, M., Jonas, J. B., Samani, N. J., Kaprio, J., Pajukanta, P., Adair, L. S., Bechayda, S. A., de Silva, H. J., Wickremasinghe, A. R., Krauss, R. M., Wu, J., Zheng, W., den Hollander, A. I., Bharadwaj, D., Correa, A., Wilson, J. G., Lind, L., Heng, C., Nelson, A. E., Golightly, Y. M., Wilson, J. F., Penninx, B., Kim, H., Attia, J., Scott, R. J., Rao, D. C., Arnett, D. K., Walker, M., Koistinen, H. A., Chandak, G. R., Yajnik, C. S., Mercader, J. M., Tusie-Luna, T., Aguilar-Salinas, C. A., Villalpando, C. G., Orozco, L., Fornage, M., Tai, E. S., van Dam, R. M., Lehtimaki, T., Chaturvedi, N., Yokota, M., Liu, J., Reilly, D. F., McKnight, A. J., Kee, F., Jockel, K., McCarthy, M. I., Palmer, C. N., Vitart, V., Hayward, C., Simonsick, E., van Duijn, C. M., Lu, F., Qu, J., Hishigaki, H., Lin, X., Marz, W., Parra, E. J., Cruz, M., Gudnason, V., Tardif, J., Lettre, G., 't Hart, L. M., Elders, P. J., Damrauer, S. M., Kumari, M., Kivimaki, M., van der Harst, P., Spector, T. D., Loos, R. J., Province, M. A., Psaty, B. M., Brandslund, I., Pramstaller, P. P., Christensen, K., Ripatti, S., Widen, E., Hakonarson, H., Grant, S. F., Kiemeney, L. A., de Graaf, J., Loeffler, M., Kronenberg, F., Gu, D., Erdmann, J., Schunkert, H., Franks, P. W., Linneberg, A., Jukema, J. W., Khera, A. V., Mannikko, M., Jarvelin, M., Kutalik, Z., Cucca, F., Mook-Kanamori, D. O., van Dijk, K. W., Watkins, H., Strachan, D. P., Grarup, N., Sever, P., Poulter, N., Rotter, J. I., Dantoft, T. M., Karpe, F., Neville, M. J., Timpson, N. J., Cheng, C., Wong, T., Khor, C. C., Sabanayagam, C., Peters, A., Gieger, C., Hattersley, A. T., Pedersen, N. L., Magnusson, P. K., Boomsma, D. I., de Geus, E. J., Cupples, L. A., van Meurs, J. B., Ghanbari, M., Gordon-Larsen, P., Huang, W., Kim, Y. J., Tabara, Y., Wareham, N. J., Langenberg, C., Zeggini, E., Kuusisto, J., Laakso, M., Ingelsson, E., Abecasis, G., Chambers, J. C., Kooner, J. S., de Vries, P. S., Morrison, A. C., North, K. E., Daviglus, M., Kraft, P., Martin, N. G., Whitfield, J. B., Abbas, S., Saleheen, D., Walters, R. G., Holmes, M. V., Black, C., Smith, B. H., Justice, A. E., Baras, A., Buring, J. E., Ridker, P. M., Chasman, D. I., Kooperberg, C., Wei, W., Jarvik, G. P., Namjou, B., Hayes, M. G., Ritchie, M. D., Jousilahti, P., Salomaa, V., Hveem, K., Asvold, B. O., Kubo, M., Kamatani, Y., Okada, Y., Murakami, Y., Thorsteinsdottir, U., Stefansson, K., Ho, Y., Lynch, J. A., Rader, D. J., Tsao, P. S., Chang, K., Cho, K., O'Donnell, C. J., Gaziano, J. M., Wilson, P., Rotimi, C. N., Hazelhurst, S., Ramsay, M., Trembath, R. C., van Heel, D. A., Tamiya, G., Yamamoto, M., Kim, B., Mohlke, K. L., Frayling, T. M., Hirschhorn, J. N., Kathiresan, S., VA Million Veteran Program, Global Lipids Genetics Consortium*, Boehnke, M., Natarajan, P., Peloso, G. M., Brown, C. D., Morris, A. P., Assimes, T. L., Deloukas, P., Sun, Y. V., Willer, C. J. 2021

    Abstract

    Increased blood lipid levels are heritable risk factors of cardiovascular disease with varied prevalence worldwide owing to different dietary patterns and medication use1. Despite advances in prevention and treatment, in particular through reducing low-density lipoprotein cholesterol levels2, heart disease remains the leading cause of death worldwide3. Genome-wideassociation studies (GWAS) of blood lipid levels have led to important biological and clinical insights, as well as new drug targets, for cardiovascular disease. However, most previous GWAS4-23 have been conducted in European ancestry populations and may have missed genetic variants that contribute to lipid-level variation in other ancestry groups. These include differences in allele frequencies, effect sizes and linkage-disequilibrium patterns24. Here we conduct a multi-ancestry, genome-wide genetic discovery meta-analysis of lipid levels in approximately 1.65million individuals, including 350,000 of non-European ancestries. We quantify the gain in studying non-European ancestries and provide evidence to support the expansion of recruitment of additional ancestries, even with relatively small sample sizes. We find that increasing diversity rather than studying additional individuals of European ancestry results in substantial improvements in fine-mapping functional variants and portability of polygenic prediction (evaluated in approximately295,000 individuals from 7ancestry groupings). Modest gains in the number of discovered loci and ancestry-specific variants were also achieved. As GWAS expand emphasis beyond the identification of genes and fundamental biology towards the use of genetic variants for preventive and precision medicine25, we anticipate that increased diversity of participants will lead to more accurate and equitable26 application of polygenic scores in clinical practice.

    View details for DOI 10.1038/s41586-021-04064-3

    View details for PubMedID 34887591

  • Genetic Architecture of Abdominal Aortic Aneurysm in the Million Veteran Program. Circulation Klarin, D. n., Verma, S. S., Judy, R. n., Dikilitas, O. n., Wolford, B. N., Paranjpe, I. n., Levin, M. G., Pan, C. n., Tcheandjieu, C. n., Spin, J. M., Lynch, J. n., Assimes, T. L., Nyrønning, L. Å., Mattsson, E. n., Edwards, T. L., Denny, J. n., Larson, E. n., Lee, M. T., Carrell, D. n., Zhang, Y. n., Jarvik, G. P., Gharavi, A. G., Harley, J. n., Mentch, F. n., Pacheco, J. A., Hakonarson, H. n., Skogholt, A. H., Thomas, L. n., Gabrielsen, M. E., Hveem, K. n., Nielsen, J. B., Zhou, W. n., Fritsche, L. n., Huang, J. n., Natarajan, P. n., Sun, Y. V., DuVall, S. L., Rader, D. J., Cho, K. n., Chang, K. M., Wilson, P. W., O'Donnell, C. J., Kathiresan, S. n., Scali, S. T., Berceli, S. A., Willer, C. n., Jones, G. T., Bown, M. J., Nadkarni, G. n., Kullo, I. J., Ritchie, M. n., Damrauer, S. M., Tsao, P. S. 2020

    View details for DOI 10.1161/CIRCULATIONAHA.120.047544

    View details for PubMedID 32981348

  • Genome-wide association study of peripheral artery disease in the Million Veteran Program. Nature medicine Klarin, D., Lynch, J., Aragam, K., Chaffin, M., Assimes, T. L., Huang, J., Lee, K. M., Shao, Q., Huffman, J. E., Natarajan, P., Arya, S., Small, A., Sun, Y. V., Vujkovic, M., Freiberg, M. S., Wang, L., Chen, J., Saleheen, D., Lee, J. S., Miller, D. R., Reaven, P., Alba, P. R., Patterson, O. V., DuVall, S. L., Boden, W. E., Beckman, J. A., Gaziano, J. M., Concato, J., Rader, D. J., Cho, K., Chang, K., Wilson, P. W., O'Donnell, C. J., Kathiresan, S., VA Million Veteran Program, Tsao, P. S., Damrauer, S. M. 2019

    Abstract

    Peripheral artery disease (PAD) is a leading cause of cardiovascular morbidity and mortality; however, the extent to which genetic factors increase risk for PAD is largely unknown. Using electronic health record data, we performed a genome-wide association study in the Million Veteran Program testing ~32 million DNA sequence variants with PAD (31,307 cases and 211,753 controls) across veterans of European, African and Hispanic ancestry. The results were replicated in an independent sample of 5,117 PAD cases and 389,291 controls from the UK Biobank. We identified 19 PAD loci, 18 of which have not been previously reported. Eleven of the 19 loci were associated with disease in three vascular beds (coronary, cerebral, peripheral), including LDLR, LPL and LPA, suggesting that therapeutic modulation of low-density lipoprotein cholesterol, the lipoprotein lipase pathway or circulating lipoprotein(a) may be efficacious for multiple atherosclerotic disease phenotypes. Conversely, four of the variants appeared to be specific for PAD, including F5 p.R506Q, highlighting the pathogenic role of thrombosis in the peripheral vascular bed and providing genetic support for Factor Xa inhibition as a therapeutic strategy for PAD. Our results highlight mechanistic similarities and differences among coronary, cerebral and peripheral atherosclerosis and provide therapeutic insights.

    View details for DOI 10.1038/s41591-019-0492-5

    View details for PubMedID 31285632

  • Decoding the Genomics of Abdominal Aortic Aneurysm. Cell Li, J., Pan, C., Zhang, S., Spin, J. M., Deng, A., Leung, L. L., Dalman, R. L., Tsao, P. S., Snyder, M. 2018; 174 (6): 1361

    Abstract

    A key aspect of genomic medicine is to make individualized clinical decisions from personal genomes. We developed a machine-learning framework to integrate personal genomes and electronic health record (EHR) data and used this framework to study abdominal aortic aneurysm (AAA), a prevalent irreversible cardiovascular disease with unclear etiology. Performing whole-genome sequencing on AAA patients and controls, we demonstrated its predictive precision solely from personal genomes. By modeling personal genomes with EHRs, this framework quantitatively assessed the effectiveness of adjusting personal lifestyles given personal genome baselines, demonstrating its utility as a personal health management tool. We showed that this new framework agnostically identified genetic components involved in AAA, which were subsequently validated in human aortic tissues and in murine models. Our study presents a new framework for disease genome analysis, which can be used for both health management and understanding the biological architecture of complex diseases. VIDEO ABSTRACT.

    View details for PubMedID 30193110

  • Segmental Aortic Stiffening Contributes to Experimental Abdominal Aortic Aneurysm Development CIRCULATION Raaz, U., Zoellner, A. M., Schellinger, I. N., Toh, R., Nakagami, F., Brandt, M., Emrich, F. C., Kayama, Y., Eken, S., Adam, M., Maegdefessel, L., Hertel, T., Deng, A., Jagger, A., Buerke, M., Dalman, R. L., Spin, J. M., Kuhl, E., Tsao, P. S. 2015; 131 (20): 1783-1795

    Abstract

    Stiffening of the aortic wall is a phenomenon consistently observed in age and in abdominal aortic aneurysm (AAA). However, its role in AAA pathophysiology is largely undefined.Using an established murine elastase-induced AAA model, we demonstrate that segmental aortic stiffening precedes aneurysm growth. Finite-element analysis reveals that early stiffening of the aneurysm-prone aortic segment leads to axial (longitudinal) wall stress generated by cyclic (systolic) tethering of adjacent, more compliant wall segments. Interventional stiffening of AAA-adjacent aortic segments (via external application of surgical adhesive) significantly reduces aneurysm growth. These changes correlate with the reduced segmental stiffness of the AAA-prone aorta (attributable to equalized stiffness in adjacent segments), reduced axial wall stress, decreased production of reactive oxygen species, attenuated elastin breakdown, and decreased expression of inflammatory cytokines and macrophage infiltration, and attenuated apoptosis within the aortic wall, as well. Cyclic pressurization of segmentally stiffened aortic segments ex vivo increases the expression of genes related to inflammation and extracellular matrix remodeling. Finally, human ultrasound studies reveal that aging, a significant AAA risk factor, is accompanied by segmental infrarenal aortic stiffening.The present study introduces the novel concept of segmental aortic stiffening as an early pathomechanism generating aortic wall stress and triggering aneurysmal growth, thereby delineating potential underlying molecular mechanisms and therapeutic targets. In addition, monitoring segmental aortic stiffening may aid the identification of patients at risk for AAA.

    View details for DOI 10.1161/CIRCULATIONAHA.114.012377

    View details for PubMedID 25904646

  • miR-24 limits aortic vascular inflammation and murine abdominal aneurysm development NATURE COMMUNICATIONS Maegdefessel, L., Spin, J. M., Raaz, U., Eken, S. M., Toh, R., Azuma, J., Adam, M., Nagakami, F., Heymann, H. M., Chernugobova, E., Jin, H., Roy, J., Hultgren, R., Caidahl, K., Schrepfer, S., Hamsten, A., Eriksson, P., McConnell, M. V., Dalman, R. L., Tsao, P. S. 2014; 5

    Abstract

    Identification and treatment of abdominal aortic aneurysm (AAA) remain among the most prominent challenges in vascular medicine. MicroRNAs (miRNAs) are crucial regulators of cardiovascular pathology and represent intriguing targets to limit AAA expansion. Here we show, by using two established murine models of AAA disease along with human aortic tissue and plasma analysis, that miR-24 is a key regulator of vascular inflammation and AAA pathology. In vivo and in vitro studies reveal chitinase 3-like 1 (Chi3l1) to be a major target and effector under the control of miR-24, regulating cytokine synthesis in macrophages as well as their survival, promoting aortic smooth muscle cell migration and cytokine production, and stimulating adhesion molecule expression in vascular endothelial cells. We further show that modulation of miR-24 alters AAA progression in animal models, and that miR-24 and CHI3L1 represent novel plasma biomarkers of AAA disease progression in humans.

    View details for DOI 10.1038/ncomms6214

    View details for Web of Science ID 000343982800003

    View details for PubMedCentralID PMC4217126

  • Pathogenesis of Abdominal Aortic Aneurysms: MicroRNAs, Proteases, Genetic Associations. Annual review of medicine Maegdefessel, L., Dalman, R. L., Tsao, P. S. 2014; 65: 49-62

    Abstract

    Abdominal aortic aneurysm (AAA) disease is a common, morbid, and highly lethal pathology. Extraordinary efforts have been launched to determine the molecular and pathophysiological characteristics of AAAs. Although surgery is highly effective in preventing death by rupture for larger AAAs, no guidance or preventive therapy is currently available for the >90% of patients whose aneurysms are below the surgical threshold. Predictive animal models of AAA as well as human pathological samples have revealed a complex circuit of AAA formation and progression. The proteolytic destruction of matrix components of the aorta by different proteases has been extensively studied over many years. Recently, a novel class of small noncoding RNAs, called microRNAs, was identified as "fine-tuners" of the translational output of target genes; they act by promoting mRNA degradation. Their therapeutic potential in limiting AAA development appears very intriguing. Further, current studies assessing genetic and heritable associations for AAA disease have provided great insight into its pathogenesis, potentially enabling us to better clinically manage affected patients.

    View details for DOI 10.1146/annurev-med-101712-174206

    View details for PubMedID 24274177

  • MicroRNA-21 Blocks Abdominal Aortic Aneurysm Development and Nicotine-Augmented Expansion SCIENCE TRANSLATIONAL MEDICINE Maegdefessel, L., Azuma, J., Toh, R., Deng, A., Merk, D. R., Raiesdana, A., Leeper, N. J., Raaz, U., Schoelmerich, A. M., McConnell, M. V., Dalman, R. L., Spin, J. M., Tsao, P. S. 2012; 4 (122)

    Abstract

    Identification and treatment of abdominal aortic aneurysm (AAA) remains among the most prominent challenges in vascular medicine. MicroRNAs are crucial regulators of cardiovascular pathology and represent possible targets for the inhibition of AAA expansion. We identified microRNA-21 (miR-21) as a key modulator of proliferation and apoptosis of vascular wall smooth muscle cells during development of AAA in two established murine models. In both models (AAA induced by porcine pancreatic elastase or infusion of angiotensin II), miR-21 expression increased as AAA developed. Lentiviral overexpression of miR-21 induced cell proliferation and decreased apoptosis in the aortic wall, with protective effects on aneurysm expansion. miR-21 overexpression substantially decreased expression of the phosphatase and tensin homolog (PTEN) protein, leading to increased phosphorylation and activation of AKT, a component of a pro-proliferative and antiapoptotic pathway. Systemic injection of a locked nucleic acid-modified antagomir targeting miR-21 diminished the pro-proliferative impact of down-regulated PTEN, leading to a marked increase in the size of AAA. Similar results were seen in mice with AAA augmented by nicotine and in human aortic tissue samples from patients undergoing surgical repair of AAA (with more pronounced effects observed in smokers). Modulation of miR-21 expression shows potential as a new therapeutic option to limit AAA expansion and vascular disease progression.

    View details for DOI 10.1126/scitranslmed.3003441

    View details for PubMedID 22357537

  • Inhibition of microRNA-29b reduces murine abdominal aortic aneurysm development JOURNAL OF CLINICAL INVESTIGATION Maegdefessel, L., Azuma, J., Toh, R., Merk, D. R., Deng, A., Chin, J. T., Raaz, U., Schoelmerich, A. M., Raiesdana, A., Leeper, N. J., McConnell, M. V., Dalman, R. L., Spin, J. M., Tsao, P. S. 2012; 122 (2): 497-506

    Abstract

    MicroRNAs (miRs) regulate gene expression at the posttranscriptional level and play crucial roles in vascular integrity. As such, they may have a role in modifying abdominal aortic aneurysm (AAA) expansion, the pathophysiological mechanisms of which remain incompletely explored. Here, we investigate the role of miRs in 2 murine models of experimental AAA: the porcine pancreatic elastase (PPE) infusion model in C57BL/6 mice and the AngII infusion model in Apoe-/- mice. AAA development was accompanied by decreased aortic expression of miR-29b, along with increased expression of known miR-29b targets, Col1a1, Col3a1, Col5a1, and Eln, in both models. In vivo administration of locked nucleic acid anti-miR-29b greatly increased collagen expression, leading to an early fibrotic response in the abdominal aortic wall and resulting in a significant reduction in AAA progression over time in both models. In contrast, overexpression of miR-29b using a lentiviral vector led to augmented AAA expansion and significant increase of aortic rupture rate. Cell culture studies identified aortic fibroblasts as the likely vascular cell type mediating the profibrotic effects of miR-29b modulation. A similar pattern of reduced miR-29b expression and increased target gene expression was observed in human AAA tissue samples compared with that in organ donor controls. These data suggest that therapeutic manipulation of miR-29b and its target genes holds promise for limiting AAA disease progression and protecting from rupture.

    View details for DOI 10.1172/JCI61598

    View details for PubMedID 22269326

  • Genetic drivers of heterogeneity in type 2 diabetes pathophysiology. Nature Suzuki, K., Hatzikotoulas, K., Southam, L., Taylor, H. J., Yin, X., Lorenz, K. M., Mandla, R., Huerta-Chagoya, A., Melloni, G. E., Kanoni, S., Rayner, N. W., Bocher, O., Arruda, A. L., Sonehara, K., Namba, S., Lee, S. S., Preuss, M. H., Petty, L. E., Schroeder, P., Vanderwerff, B., Kals, M., Bragg, F., Lin, K., Guo, X., Zhang, W., Yao, J., Kim, Y. J., Graff, M., Takeuchi, F., Nano, J., Lamri, A., Nakatochi, M., Moon, S., Scott, R. A., Cook, J. P., Lee, J. J., Pan, I., Taliun, D., Parra, E. J., Chai, J. F., Bielak, L. F., Tabara, Y., Hai, Y., Thorleifsson, G., Grarup, N., Sofer, T., Wuttke, M., Sarnowski, C., Gieger, C., Nousome, D., Trompet, S., Kwak, S. H., Long, J., Sun, M., Tong, L., Chen, W. M., Nongmaithem, S. S., Noordam, R., Lim, V. J., Tam, C. H., Joo, Y. Y., Chen, C. H., Raffield, L. M., Prins, B. P., Nicolas, A., Yanek, L. R., Chen, G., Brody, J. A., Kabagambe, E., An, P., Xiang, A. H., Choi, H. S., Cade, B. E., Tan, J., Broadaway, K. A., Williamson, A., Kamali, Z., Cui, J., Thangam, M., Adair, L. S., Adeyemo, A., Aguilar-Salinas, C. A., Ahluwalia, T. S., Anand, S. S., Bertoni, A., Bork-Jensen, J., Brandslund, I., Buchanan, T. A., Burant, C. F., Butterworth, A. S., Canouil, M., Chan, J. C., Chang, L. C., Chee, M. L., Chen, J., Chen, S. H., Chen, Y. T., Chen, Z., Chuang, L. M., Cushman, M., Danesh, J., Das, S. K., de Silva, H. J., Dedoussis, G., Dimitrov, L., Doumatey, A. P., Du, S., Duan, Q., Eckardt, K. U., Emery, L. S., Evans, D. S., Evans, M. K., Fischer, K., Floyd, J. S., Ford, I., Franco, O. H., Frayling, T. M., Freedman, B. I., Genter, P., Gerstein, H. C., Giedraitis, V., González-Villalpando, C., González-Villalpando, M. E., Gordon-Larsen, P., Gross, M., Guare, L. A., Hackinger, S., Hakaste, L., Han, S., Hattersley, A. T., Herder, C., Horikoshi, M., Howard, A. G., Hsueh, W., Huang, M., Huang, W., Hung, Y. J., Hwang, M. Y., Hwu, C. M., Ichihara, S., Ikram, M. A., Ingelsson, M., Islam, M. T., Isono, M., Jang, H. M., Jasmine, F., Jiang, G., Jonas, J. B., Jørgensen, T., Kamanu, F. K., Kandeel, F. R., Kasturiratne, A., Katsuya, T., Kaur, V., Kawaguchi, T., Keaton, J. M., Kho, A. N., Khor, C. C., Kibriya, M. G., Kim, D. H., Kronenberg, F., Kuusisto, J., Läll, K., Lange, L. A., Lee, K. M., Lee, M. S., Lee, N. R., Leong, A., Li, L., Li, Y., Li-Gao, R., Ligthart, S., Lindgren, C. M., Linneberg, A., Liu, C. T., Liu, J., Locke, A. E., Louie, T., Luan, J., Luk, A. O., Luo, X., Lv, J., Lynch, J. A., Lyssenko, V., Maeda, S., Mamakou, V., Mansuri, S. R., Matsuda, K., Meitinger, T., Melander, O., Metspalu, A., Mo, H., Morris, A. D., Moura, F. A., Nadler, J. L., Nalls, M. A., Nayak, U., Ntalla, I., Okada, Y., Orozco, L., Patel, S. R., Patil, S., Pei, P., Pereira, M. A., Peters, A., Pirie, F. J., Polikowsky, H. G., Porneala, B., Prasad, G., Rasmussen-Torvik, L. J., Reiner, A. P., Roden, M., Rohde, R., Roll, K., Sabanayagam, C., Sandow, K., Sankareswaran, A., Sattar, N., Schönherr, S., Shahriar, M., Shen, B., Shi, J., Shin, D. M., Shojima, N., Smith, J. A., So, W. Y., Stančáková, A., Steinthorsdottir, V., Stilp, A. M., Strauch, K., Taylor, K. D., Thorand, B., Thorsteinsdottir, U., Tomlinson, B., Tran, T. C., Tsai, F. J., Tuomilehto, J., Tusie-Luna, T., Udler, M. S., Valladares-Salgado, A., van Dam, R. M., van Klinken, J. B., Varma, R., Wacher-Rodarte, N., Wheeler, E., Wickremasinghe, A. R., van Dijk, K. W., Witte, D. R., Yajnik, C. S., Yamamoto, K., Yamamoto, K., Yoon, K., Yu, C., Yuan, J. M., Yusuf, S., Zawistowski, M., Zhang, L., Zheng, W., Raffel, L. J., Igase, M., Ipp, E., Redline, S., Cho, Y. S., Lind, L., Province, M. A., Fornage, M., Hanis, C. L., Ingelsson, E., Zonderman, A. B., Psaty, B. M., Wang, Y. X., Rotimi, C. N., Becker, D. M., Matsuda, F., Liu, Y., Yokota, M., Kardia, S. L., Peyser, P. A., Pankow, J. S., Engert, J. C., Bonnefond, A., Froguel, P., Wilson, J. G., Sheu, W. H., Wu, J. Y., Hayes, M. G., Ma, R. C., Wong, T. Y., Mook-Kanamori, D. O., Tuomi, T., Chandak, G. R., Collins, F. S., Bharadwaj, D., Paré, G., Sale, M. M., Ahsan, H., Motala, A. A., Shu, X. O., Park, K. S., Jukema, J. W., Cruz, M., Chen, Y. I., Rich, S. S., McKean-Cowdin, R., Grallert, H., Cheng, C. Y., Ghanbari, M., Tai, E. S., Dupuis, J., Kato, N., Laakso, M., Köttgen, A., Koh, W. P., Bowden, D. W., Palmer, C. N., Kooner, J. S., Kooperberg, C., Liu, S., North, K. E., Saleheen, D., Hansen, T., Pedersen, O., Wareham, N. J., Lee, J., Kim, B. J., Millwood, I. Y., Walters, R. G., Stefansson, K., Ahlqvist, E., Goodarzi, M. O., Mohlke, K. L., Langenberg, C., Haiman, C. A., Loos, R. J., Florez, J. C., Rader, D. J., Ritchie, M. D., Zöllner, S., Mägi, R., Marston, N. A., Ruff, C. T., van Heel, D. A., Finer, S., Denny, J. C., Yamauchi, T., Kadowaki, T., Chambers, J. C., Ng, M. C., Sim, X., Below, J. E., Tsao, P. S., Chang, K. M., McCarthy, M. I., Meigs, J. B., Mahajan, A., Spracklen, C. N., Mercader, J. M., Boehnke, M., Rotter, J. I., Vujkovic, M., Voight, B. F., Morris, A. P., Zeggini, E. 2024

    Abstract

    Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes1,2 and molecular mechanisms that are often specific to cell type3,4. Here, to characterize the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study data from 2,535,601 individuals (39.7% not of European ancestry), including 428,452 cases of T2D. We identify 1,289 independent association signals at genome-wide significance (P < 5 × 10-8) that map to 611 loci, of which 145 loci are, to our knowledge, previously unreported. We define eight non-overlapping clusters of T2D signals that are characterized by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type-specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial cells and enteroendocrine cells. We build cluster-specific partitioned polygenic scores5 in a further 279,552 individuals of diverse ancestry, including 30,288 cases of T2D, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned polygenic scores are associated with coronary artery disease, peripheral artery disease and end-stage diabetic nephropathy across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings show the value of integrating multi-ancestry genome-wide association study data with single-cell epigenomics to disentangle the aetiological heterogeneity that drives the development and progression of T2D. This might offer a route to optimize global access to genetically informed diabetes care.

    View details for DOI 10.1038/s41586-024-07019-6

    View details for PubMedID 38374256

    View details for PubMedCentralID 6518376

  • Mitochondrial Transplantation promotes protective effector and memory CD4+ T cell response during Mycobacterium tuberculosis infection and diminishes exhaustion and senescence in elderly CD4+ T cells. bioRxiv : the preprint server for biology Headley, C. A., Gautam, S., Olmo-Fontanez, A., Garcia-Vilanova, A., Dwivedi, V., Schami, A., Weintraub, S., Tsao, P. S., Torrelles, J. B., Turner, J. 2024

    Abstract

    Tuberculosis (TB), caused by the bacterium Mycobacterium tuberculosis (M.tb), remains a significant health concern worldwide, especially in populations with weakened or compromised immune systems, such as the elderly. Proper adaptive immune function, particularly a CD4+ T cell response, is central to host immunity against M.tb. Chronic infections, such as M.tb, as well as aging promote T cell exhaustion and senescence, which can impair immune control and promote progression to TB disease. Mitochondrial dysfunction contributes to T cell dysfunction, both in aging and chronic infections and diseases. Mitochondrial perturbations can disrupt cellular metabolism, enhance oxidative stress, and impair T-cell signaling and effector functions. This study examined the impact of mitochondrial transplantation (mito-transfer) on CD4+ T cell differentiation and function using aged mouse models and human CD4+ T cells from elderly individuals. Our study revealed that mito-transfer in naïve CD4+ T cells promoted the generation of protective effector and memory CD4+ T cells during M.tb infection in mice. Further, mito-transfer enhanced the function of elderly human T cells by increasing their mitochondrial mass and modulating cytokine production, which in turn reduced exhaustion and senescence cell markers. Our results suggest that mito-transfer could be a novel strategy to reestablish aged CD4+ T cell function, potentially improving immune responses in the elderly and chronic TB patients, with a broader implication for other diseases where mitochondrial dysfunction is linked to T cell exhaustion and senescence.

    View details for DOI 10.1101/2024.01.24.577036

    View details for PubMedID 38328206

    View details for PubMedCentralID PMC10849707

  • Can Metformin reduce AAA risk? A Mendelian randomisation study Saxby, K., Dudbridge, F., Roychowdhury, T., Klarin, D., Jones, G., Tsao, P., Damrauer, S., Bown, M., Nelson, C. SPRINGERNATURE. 2024: 416
  • Investigation of genomic and transcriptomic risk factors in clopidogrel response in African Americans. medRxiv : the preprint server for health sciences Yang, G., Alarcon, C., Chanfreau, C., Lee, N. H., Friedman, P., Nutescu, E., Tuck, M., O'Brien, T., Gong, L., Klein, T. E., Chang, K. M., Tsao, P. S., Meltzer, D. O., Tuteja, S., Perera, M. A. 2023

    Abstract

    Clopidogrel, an anti-platelet drug, used to prevent thrombosis after percutaneous coronary intervention. Clopidogrel resistance results in recurring ischemic episodes, with African Americans suffering disproportionately. The aim of this study was to identify biomarkers of clopidogrel resistance in African American patients. We conducted a genome-wide association study, including local ancestry adjustment, in 141 African Americans on clopidogrel to identify associations with high on-treatment platelet reactivity (HTPR). We validated genome-wide and suggestive hits in an independent cohort of African American clopidogrel patients (N = 823) from the Million Veteran's Program (MVP) along with in vitro functional follow up. We performed differential gene expression (DGE) analysis in whole blood with functional follow-up in MEG-01 cells. We identified rs7807369, within thrombospondin 7A (THSD7A), as significantly associated with increasing risk of HTPR (p = 4.56 × 10-9). Higher THSD7A expression was associated with HTPR in an independent gene expression cohort of clopidogrel treated patients (p = 0.004) and supported by increased gene expression on THSD7A in primary human endothelial cells carrying the risk haplotype. Two SNPs (rs1149515 and rs191786) were validated in the MVP cohort. DGE analysis identified an association with decreased LAIR1 expression to HTPR. LAIR1 knockdown in a MEG-01 cells resulted in increased expression of SYK and AKT1, suggesting an inhibitory role of LAIR1 in the Glycoprotein VI pathway. Notably, the CYP2C19 variants showed no association with clopidogrel response in the discovery or MVP cohorts. In summary, these finding suggest that other variants outside of CYP2C19 star alleles play an important role in clopidogrel response in African Americans.

    View details for DOI 10.1101/2023.12.05.23299140

    View details for PubMedID 38106031

    View details for PubMedCentralID PMC10723512

  • Profiling the genome and proteome of metabolic dysfunction-associated steatotic liver disease identifies potential therapeutic targets. medRxiv : the preprint server for health sciences Liu, J., Hu, S., Chen, L., Daly, C., Prada Medina, C. A., Richardson, T. G., Traylor, M., Dempster, N. J., Mbasu, R., Monfeuga, T., Vujkovic, M., Tsao, P. S., Lynch, J. A., Voight, B. F., Chang, K. M., Million, V. A., Cobbold, J. F., Tomlinson, J. W., van Duijn, C. M., Howson, J. M. 2023

    Abstract

    Metabolic dysfunction-associated steatotic liver disease (MASLD) affects over 25% of the population and currently has no effective treatments. Plasma proteins with causal evidence may represent promising drug targets. We aimed to identify plasma proteins in the causal pathway of MASLD and explore their interaction with obesity.We analysed 2,941 plasma proteins in 43,978 European participants from UK Biobank. We performed genome-wide association study (GWAS) for all MASLD-associated proteins and created the largest MASLD GWAS (109,885 cases/1,014,923 controls). We performed Mendelian Randomization (MR) and integrated proteins and their encoding genes in MASLD ranges to identify candidate causal proteins. We then validated them through independent replication, exome sequencing, liver imaging, bulk and single-cell gene expression, liver biopsies, pathway, and phenome-wide data. We explored the role of obesity by MR and multivariable MR across proteins, body mass index, and MASLD.We found 929 proteins associated with MASLD, reported five novel genetic loci associated with MASLD, and identified 17 candidate MASLD protein targets. We identified four novel targets for MASLD (CD33, GRHPR, HMOX2, and SCG3), provided protein evidence supporting roles of AHCY, FCGR2B, ORM1, and RBKS in MASLD, and validated nine previously known targets. We found that CD33, FCGR2B, ORM1, RBKS, and SCG3 mediated the association of obesity and MASLD, and HMOX2, ORM1, and RBKS had effect on MASLD independent of obesity.This study identified new protein targets in the causal pathway of MASLD, providing new insights into the multi-omics architecture and pathophysiology of MASLD. These findings advise further therapeutic interventions for MASLD.

    View details for DOI 10.1101/2023.11.30.23299247

    View details for PubMedID 38076879

    View details for PubMedCentralID PMC10705663

  • Extracellular Delivery of Functional Mitochondria Rescues the Dysfunction of CD4+T Cells in Aging. Advanced science (Weinheim, Baden-Wurttemberg, Germany) Headley, C. A., Gautam, S., Olmo-Fontanez, A., Garcia-Vilanova, A., Dwivedi, V., Akhter, A., Schami, A., Chiem, K., Ault, R., Zhang, H., Cai, H., Whigham, A., Delgado, J., Hicks, A., Tsao, P. S., Gelfond, J., Martinez-Sobrido, L., Wang, Y., Torrelles, J. B., Turner, J. 2023: e2303664

    Abstract

    Mitochondrial dysfunction alters cellular metabolism, increases tissue oxidative stress, and may be principal to the dysregulated signaling and function of CD4+ T lymphocytes in the elderly. In this proof of principle study, it is investigated whether the transfer of functional mitochondria into CD4+ T cells that are isolated from old mice (aged CD4+ T cells), can abrogate aging-associated mitochondrial dysfunction, and improve the aged CD4+ T cell functionality. The results show that the delivery of exogenous mitochondria to aged non-activated CD4+ T cells led to significant mitochondrial proteome alterations highlighted by improved aerobic metabolism and decreased cellular mitoROS. Additionally, mito-transferred aged CD4+ T cells showed improvements in activation-induced TCR-signaling kinetics displaying markers of activation (CD25), increased IL-2 production, enhanced proliferation ex vivo. Importantly, immune deficient mouse models (RAG-KO) showed that adoptive transfer of mito-transferred naive aged CD4+ T cells, protected recipient mice from influenza A and Mycobacterium tuberculosis infections. These findings support mitochondria as targets of therapeutic intervention in aging.

    View details for DOI 10.1002/advs.202303664

    View details for PubMedID 37990641

  • CXCL12 regulates coronary artery dominance in diverse populations and links development to disease. medRxiv : the preprint server for health sciences Rios Coronado, P. E., Zanetti, D., Zhou, J., Naftaly, J. A., Prabala, P., Kho, P. F., Martínez Jaimes, A. M., Hilliard, A. T., Pyarajan, S., Dochtermann, D., Chang, K. M., Winn, V. D., Pașca, A. M., Plomondon, M. E., Waldo, S. W., Tsao, P. S., Clarke, S. L., Red-Horse, K., Assimes, T. L. 2023

    Abstract

    Mammalian cardiac muscle is supplied with blood by right and left coronary arteries that form branches covering both ventricles of the heart. Whether branches of the right or left coronary arteries wrap around to the inferior side of the left ventricle is variable in humans and termed right or left dominance. Coronary dominance is likely a heritable trait, but its genetic architecture has never been explored. Here, we present the first large-scale multi-ancestry genome-wide association study of dominance in 61,043 participants of the VA Million Veteran Program, including over 10,300 Africans and 4,400 Admixed Americans. Dominance was moderately heritable with ten loci reaching genome wide significance. The most significant mapped to the chemokine CXCL12 in both Europeans and Africans. Whole-organ imaging of human fetal hearts revealed that dominance is established during development in locations where CXCL12 is expressed. In mice, dominance involved the septal coronary artery, and its patterning was altered with Cxcl12 deficiency. Finally, we linked human dominance patterns with coronary artery disease through colocalization, genome-wide genetic correlation and Mendelian Randomization analyses. Together, our data supports CXCL12 as a primary determinant of coronary artery dominance in humans of diverse backgrounds and suggests that developmental patterning of arteries may influence one's susceptibility to ischemic heart disease.

    View details for DOI 10.1101/2023.10.27.23297507

    View details for PubMedID 37961706

    View details for PubMedCentralID PMC10635223

  • CYP2C19 Polymorphisms and Clinical Outcomes Following Percutaneous Coronary Intervention (PCI) in the Million Veterans Program. medRxiv : the preprint server for health sciences Chanfreau-Coffinier, C., Friede, K. A., Plomondon, M. E., Lee, K. M., Lu, Z., Lynch, J. A., DuVall, S. L., Vassy, J. L., Waldo, S. W., Cleator, J. H., Maddox, T. M., Rader, D. J., Assimes, T. L., Damrauer, S. M., Tsao, P. S., Chang, K. M., Voora, D., Giri, J., Tuteja, S. 2023

    Abstract

    CYP2C19 loss-of-function (LOF) alleles decrease the antiplatelet effect of clopidogrel following percutaneous coronary intervention (PCI) in patients presenting with acute coronary syndrome (ACS). The impact of genotype in stable ischemic heart disease (SIHD) is unclear.Determine the association of CYP2C19 genotype with major adverse cardiac events (MACE) after PCI for ACS or SIHD.Million Veterans Program (MVP) participants age <65 years with a PCI documented in the VA Clinical Assessment, Reporting and Tracking (CART) Program between 1/1/2009 to 9/30/2017, treated with clopidogrel were included. Time to MACE defined as the composite of all-cause death, stroke or myocardial infarction within 12 months following PCI.Among 4,461 Veterans (mean age 59.1 ± 5.1 years, 18% Black); 44% had ACS, 56% had SIHD and 29% carried a CYP2C19 LOF allele. 301 patients (6.7%) experienced MACE while being treated with clopidogrel, 155 (7.9%) in the ACS group and 146 (5.9%) in the SIHD group. Overall, MACE was not significantly different between LOF carriers vs. noncarriers (adjusted hazard ratio [HR] 1.18, confidence interval [95%CI] 0.97-1.45, p=0.096). Among patients presenting with ACS, MACE risk in LOF carriers versus non-carriers was numerically higher (HR 1.30, 95%CI 0.98-1.73, p=0.067). There was no difference in MACE risk in patients with SIHD (HR 1.09, 95%CI 0.82-1.44; p=0.565).CYP2C19 LOF carriers presenting with ACS treated with clopidogrel following PCI experienced a numerically greater elevated risk of MACE events. CYP2C19 LOF genotype is not associated with MACE among patients presenting with SIHD.

    View details for DOI 10.1101/2023.10.25.23297578

    View details for PubMedID 37961335

    View details for PubMedCentralID PMC10635203

  • Genetic Inhibition of APOL1 Pore-Forming Function Prevents APOL1-Mediated Kidney Disease. Journal of the American Society of Nephrology : JASN Hung, A. M., Assimon, V. A., Chen, H., Yu, Z., Vlasschaert, C., Triozzi, J. L., Chan, H., Wheless, L., Wilson, O., Shah, S. C., Mack, T., Thompson, T., Matheny, M. E., Chandrasekar, S., Mozaffari, S. V., Chung, C. P., Tsao, P., Susztak, K., Siew, E. D., Estrada, K., Gaziano, J. M., Graham, R. R., Tao, R., Hoek, M., Robinson-Cohen, C., Green, E. M., Bick, A. G., Million Veteran Program, Muralidhar, S., Moser, J., Deen, J. E., Tsao, P. S., Gaziano, J. M., Hauser, E., Kilbourne, A., Luoh, S., Matheny, M., Oslin, D., Churby, L., Whitbourne, S. B., Brewer, J. V., Shayan, S. A., Selva, L. E., Pyarajan, S., Cho, K., DuVall, S. L., Brophy, M. T., Stephens, B., Connor, T., Argyres, D. P., Assimes, T., Hung, A., Kranzler, H., Aguayo, S., Ahuja, S., Alexander, K., Androulakis, X. M., Balasubramanian, P., Ballas, Z., Beckham, J., Bhushan, S., Boyko, E., Cohen, D., Dellitalia, L., Faulk, L. C., Fayad, J., Fujii, D., Gappy, S., Gesek, F., Greco, J., Godschalk, M., Gress, T. W., Gupta, S., Gutierrez, S., Harley, J., Hammer, K., Hamner, M., Hurley, R., Iruvanti, P., Jacono, F., Jhala, D., Kinlay, S., Klein, J., Landry, M., Liang, P., Liangpunsakul, S., Lichy, J., Mahan, C. S., Marrache, R., Mastorides, S., Mates, E., Mattocks, K., Meyer, P., Moorman, J., Morgan, T., Murdoch, M., Norton, J., Okusaga, O., Oursler, K. A., Palacio, A., Poon, S., Potter, E., Rauchman, M., Servatius, R., Sharma, S., Smith, R., Sriram, P., Strollo, P. J., Tandon, N., Tsao, P., Villareal, G., Wallbom, A., Walsh, J., Wells, J., Whittle, J., Whooley, M., Williams, A. E., Wilson, P., Xu, J., Yeh, S. S. 2023

    Abstract

    SIGNIFICANCE STATEMENT: African Americans are at increased risk of CKD in part due to high-risk (HR) variants in the apolipoprotein L1 (APOL1) gene, termed G1/G2. A different APOL1 variant, p.N264K, reduced the risk of CKD and ESKD among carriers of APOL1 HR variants to levels comparable with individuals with APOL1 low-risk variants in an analysis of 121,492 participants of African ancestry from the Million Veteran Program (MVP). Functional genetic studies in cell models showed that APOL1 p.N264K blocked APOL1 pore-forming function and ion channel conduction and reduced toxicity of APOL1 HR mutations. Pharmacologic inhibitors that mimic this mutation blocking APOL1-mediated pore formation may be able to prevent and/or treat APOL1-associated kidney disease.BACKGROUND: African Americans are at increased risk for nondiabetic CKD in part due to HR variants in the APOL1 gene.METHODS: We tested whether a different APOL1 variant, p.N264K, modified the association between APOL1 HR genotypes (two copies of G1/G2) and CKD in a cross-sectional analysis of 121,492 participants of African ancestry from the MVP. We replicated our findings in the Vanderbilt University Biobank (n=14,386) and National Institutes of Health All of Us (n=14,704). Primary outcome was CKD and secondary outcome was ESKD among nondiabetic patients. Primary analysis compared APOL1 HR genotypes with and without p.N264K. Secondary analyses included APOL1 low-risk genotypes and tested for interaction. In MVP, we performed sequential logistic regression models adjusting for demographics, comorbidities, medications, and ten principal components of ancestry. Functional genomic studies expressed APOL1 HR variants with and without APOL1 p.N264K in cell models.RESULTS: In the MVP cohort, 15,604 (12.8%) had two APOL1 HR variants, of which 582 (0.5%) also had APOL1 p.N264K. In MVP, 18,831 (15%) had CKD, 4177 (3%) had ESKD, and 34% had diabetes. MVP APOL1 HR, without p.N264K, was associated with increased odds of CKD (odds ratio [OR], 1.72; 95% confidence interval [CI], 1.60 to 1.85) and ESKD (OR, 3.94; 95% CI, 3.52 to 4.41). In MVP, APOL1 p.N264K mitigated the renal risk of APOL1 HR, in CKD (OR, 0.43; 95% CI, 0.28 to 0.65) and ESKD (OR, 0.19; CI 0.07 to 0.51). In the replication cohorts meta-analysis, APOL1 p.N264K mitigated the renal risk of APOL1 HR in CKD (OR, 0.40; 95% CI, 0.18 to 0.92) and ESKD (OR, 0.19; 95% CI, 0.05 to 0.79). In the mechanistic studies, APOL1 p.N264K blocked APOL1 pore-forming function and ion channel conduction and reduced toxicity of APOL1 HR variants.CONCLUSIONS: APOL1 p.N264K is associated with reduced risk of CKD and ESKD among carriers of APOL1 HR to levels comparable with individuals with APOL1 low-risk genotypes.

    View details for DOI 10.1681/ASN.0000000000000219

    View details for PubMedID 37798822

  • Admixture mapping of peripheral artery disease in a Dominican population reveals a putative risk locus on 2q35. Frontiers in genetics Cullina, S., Wojcik, G. L., Shemirani, R., Klarin, D., Gorman, B. R., Sorokin, E. P., Gignoux, C. R., Belbin, G. M., Pyarajan, S., Asgari, S., Tsao, P. S., Damrauer, S. M., Abul-Husn, N. S., Kenny, E. E. 2023; 14: 1181167

    Abstract

    Peripheral artery disease (PAD) is a form of atherosclerotic cardiovascular disease, affecting ∼8 million Americans, and is known to have racial and ethnic disparities. PAD has been reported to have a significantly higher prevalence in African Americans (AAs) compared to non-Hispanic European Americans (EAs). Hispanic/Latinos (HLs) have been reported to have lower or similar rates of PAD compared to EAs, despite having a paradoxically high burden of PAD risk factors; however, recent work suggests prevalence may differ between sub-groups. Here, we examined a large cohort of diverse adults in the BioMe biobank in New York City. We observed the prevalence of PAD at 1.7% in EAs vs. 8.5% and 9.4% in AAs and HLs, respectively, and among HL sub-groups, the prevalence was found at 11.4% and 11.5% in Puerto Rican and Dominican populations, respectively. Follow-up analysis that adjusted for common risk factors demonstrated that Dominicans had the highest increased risk for PAD relative to EAs [OR = 3.15 (95% CI 2.33-4.25), p < 6.44 × 10-14]. To investigate whether genetic factors may explain this increased risk, we performed admixture mapping by testing the association between local ancestry and PAD in Dominican BioMe participants (N = 1,813) separately from European, African, and Native American (NAT) continental ancestry tracts. The top association with PAD was an NAT ancestry tract at chromosome 2q35 [OR = 1.96 (SE = 0.16), p < 2.75 × 10-05) with 22.6% vs. 12.9% PAD prevalence in heterozygous NAT tract carriers versus non-carriers, respectively. Fine-mapping at this locus implicated tag SNP rs78529201 located within a long intergenic non-coding RNA (lincRNA) LINC00607, a gene expression regulator of key genes related to thrombosis and extracellular remodeling of endothelial cells, suggesting a putative link of the 2q35 locus to PAD etiology. Efforts to reproduce the signal in other Hispanic cohorts were unsuccessful. In summary, we showed how leveraging health system data helped understand nuances of PAD risk across HL sub-groups and admixture mapping approaches elucidated a putative risk locus in a Dominican population.

    View details for DOI 10.3389/fgene.2023.1181167

    View details for PubMedID 37600667

    View details for PubMedCentralID PMC10432698

  • Serum microRNA-501-3p is a potential diagnostic tool for detecting mild cognitive impairment: Ehime genome study. Journal of neurochemistry Toyama, K., Spin, J. M., Tsao, P. S., Maruyama, K., Osawa, H., Mogi, M., Takata, Y. 2023

    Abstract

    Tight junction disruption and dysfunction are involved in the progression of blood-brain barrier (BBB) breakdown. Recent investigations have revealed BBB disruption in patients with vascular cognitive decline. Our previous studies showed that miR-501-3p negatively regulates cerebral endothelial tight junction protein-1, resulting in the disruption of the BBB, and playing an important role in the development of vascular cognitive impairment. BBB breakdown in white matter lesions is often seen in the patients with vascular mild cognitive impairment (MCI). We therefore hypothesize that most early-phase MCI patients may demonstrate elevated expression of miR-501-3p and sought to investigate whether serum exosome miR-501-3p levels could be a clinical indicator for detecting mild cognitive impairment. One hundred and seventy-eight subjects (aged 73 [68-75] years, 53% male) were recruited for this study. The Japanese version of the Montreal Cognitive Assessment (MoCA-J) was used for detecting MCI. Serum exosome miR-501-3p expression levels were measured by qPCR methods. Patients were divided into two groups depending on whether their miR-501-3p ∆Ct values were above ("High"; n = 74) or below ("Low"; n = 104) cutoff levels determined by ROC curve. MCI was detected significantly more often in the miR-501-3p-High group (vs. -Low group, 63.5% vs. 47.1%, respectively; p < 0.05). Multivariate logistic regression analysis showed a significant association between MCI status and High miR-501-3p (odds ratio 2.662; p < 0.01), improved vs. known risk factors. In non-diabetic patients, High miR-501-3p was positively associated with MCI status (odds ratio 3.633; p < 0.01) and also positively associated with MCI status in those with atherosclerosis (odds ratio 3.219; p < 0.01). The present study demonstrates that elevated expression of blood exosomal miR-501-3p can indicate the presence of MCI in human patients. Early detection of vascular injuries may allow a reduction in progressive dementia through the management of vascular risk factors.

    View details for DOI 10.1111/jnc.15911

    View details for PubMedID 37439367

  • A multi-ancestry polygenic risk score improves risk prediction for coronary artery disease. Nature medicine Patel, A. P., Wang, M., Ruan, Y., Koyama, S., Clarke, S. L., Yang, X., Tcheandjieu, C., Agrawal, S., Fahed, A. C., Ellinor, P. T., Genes & Health Research Team; the Million Veteran Program, Tsao, P. S., Sun, Y. V., Cho, K., Wilson, P. W., Assimes, T. L., van Heel, D. A., Butterworth, A. S., Aragam, K. G., Natarajan, P., Khera, A. V. 2023

    Abstract

    Identification of individuals at highest risk of coronary artery disease (CAD)-ideally before onset-remains an important public health need. Prior studies have developed genome-wide polygenic scores to enable risk stratification, reflecting the substantial inherited component to CAD risk. Here we develop a new and significantly improved polygenic score for CAD, termed GPSMult, that incorporates genome-wide association data across five ancestries for CAD (>269,000 cases and >1,178,000 controls) and ten CAD risk factors. GPSMult strongly associated with prevalent CAD (odds ratio per standard deviation 2.14, 95% confidence interval 2.10-2.19, P<0.001) in UK Biobank participants of European ancestry, identifying 20.0% of the population with 3-fold increased risk and conversely 13.9% with 3-fold decreased risk as compared with those in the middle quintile. GPSMult was also associated with incident CAD events (hazard ratio per standard deviation 1.73, 95% confidence interval 1.70-1.76, P<0.001), identifying 3% of healthy individuals with risk of future CAD events equivalent to those with existing disease and significantly improving risk discrimination and reclassification. Across multiethnic, external validation datasets inclusive of 33,096, 124,467, 16,433 and 16,874 participants of African, European, Hispanic and South Asian ancestry, respectively, GPSMult demonstrated increased strength of associations across all ancestries and outperformed all available previously published CAD polygenic scores. These data contribute a new GPSMult for CAD to the field and provide a generalizable framework for how large-scale integration of genetic association data for CAD and related traits from diverse populations can meaningfully improve polygenic risk prediction.

    View details for DOI 10.1038/s41591-023-02429-x

    View details for PubMedID 37414900

  • Contemporary Polygenic Scores of Low-Density Lipoprotein Cholesterol and Coronary Artery Disease Predict Coronary Atherosclerosis in Adolescents and Young Adults. Circulation. Genomic and precision medicine Guarischi-Sousa, R., Salfati, E., Kho, P. F., Iyer, K. R., Hilliard, A. T., Herrington, D. M., Tsao, P. S., Clarke, S. L., Assimes, T. L. 2023: e004047

    View details for DOI 10.1161/CIRCGEN.122.004047

    View details for PubMedID 37409455

  • Diversity and Scale: Genetic Architecture of 2,068 Traits in the VA Million Veteran Program. medRxiv : the preprint server for health sciences Verma, A., Huffman, J. E., Rodriguez, A., Conery, M., Liu, M., Ho, Y. L., Kim, Y., Heise, D. A., Guare, L., Panickan, V. A., Garcon, H., Linares, F., Costa, L., Goethert, I., Tipton, R., Honerlaw, J., Davies, L., Whitbourne, S., Cohen, J., Posner, D. C., Sangar, R., Murray, M., Wang, X., Dochtermann, D. R., Devineni, P., Shi, Y., Nandi, T. N., Assimes, T. L., Brunette, C. A., Carroll, R. J., Clifford, R., Duvall, S., Gelernter, J., Hung, A., Iyengar, S. K., Joseph, J., Kember, R., Kranzler, H., Levey, D., Luoh, S. W., Merritt, V. C., Overstreet, C., Deak, J. D., Grant, S. F., Polimanti, R., Roussos, P., Sun, Y. V., Venkatesh, S., Voloudakis, G., Justice, A., Begoli, E., Ramoni, R., Tourassi, G., Pyarajan, S., Tsao, P. S., O'Donnell, C. J., Muralidhar, S., Moser, J., Casas, J. P., Bick, A. G., Zhou, W., Cai, T., Voight, B. F., Cho, K., Gaziano, M. J., Madduri, R. K., Damrauer, S. M., Liao, K. P. 2023

    Abstract

    Genome-wide association studies (GWAS) have underrepresented individuals from non-European populations, impeding progress in characterizing the genetic architecture and consequences of health and disease traits. To address this, we present a population-stratified phenome-wide GWAS followed by a multi-population meta-analysis for 2,068 traits derived from electronic health records of 635,969 participants in the Million Veteran Program (MVP), a longitudinal cohort study of diverse U.S. Veterans genetically similar to the respective African (121,177), Admixed American (59,048), East Asian (6,702), and European (449,042) superpopulations defined by the 1000 Genomes Project. We identified 38,270 independent variants associating with one or more traits at experiment-wide P<4.6×10-11 significance; fine-mapping 6,318 signals identified from 613 traits to single-variant resolution. Among these, a third (2,069) of the associations were found only among participants genetically similar to non-European reference populations, demonstrating the importance of expanding diversity in genetic studies. Our work provides a comprehensive atlas of phenome-wide genetic associations for future studies dissecting the architecture of complex traits in diverse populations.

    View details for DOI 10.1101/2023.06.28.23291975

    View details for PubMedID 37425708

    View details for PubMedCentralID PMC10327290

  • Plasma proteomic signatures of a direct measure of insulin sensitivity in two population cohorts. Diabetologia Zanetti, D., Stell, L., Gustafsson, S., Abbasi, F., Tsao, P. S., Knowles, J. W., Zethelius, B., Ärnlöv, J., Balkau, B., Walker, M., Lazzeroni, L. C., Lind, L., Petrie, J. R., Assimes, T. L. 2023

    Abstract

    The euglycaemic-hyperinsulinaemic clamp (EIC) is the reference standard for the measurement of whole-body insulin sensitivity but is laborious and expensive to perform. We aimed to assess the incremental value of high-throughput plasma proteomic profiling in developing signatures correlating with the M value derived from the EIC.We measured 828 proteins in the fasting plasma of 966 participants from the Relationship between Insulin Sensitivity and Cardiovascular disease (RISC) study and 745 participants from the Uppsala Longitudinal Study of Adult Men (ULSAM) using a high-throughput proximity extension assay. We used the least absolute shrinkage and selection operator (LASSO) approach using clinical variables and protein measures as features. Models were tested within and across cohorts. Our primary model performance metric was the proportion of the M value variance explained (R2).A standard LASSO model incorporating 53 proteins in addition to routinely available clinical variables increased the M value R2 from 0.237 (95% CI 0.178, 0.303) to 0.456 (0.372, 0.536) in RISC. A similar pattern was observed in ULSAM, in which the M value R2 increased from 0.443 (0.360, 0.530) to 0.632 (0.569, 0.698) with the addition of 61 proteins. Models trained in one cohort and tested in the other also demonstrated significant improvements in R2 despite differences in baseline cohort characteristics and clamp methodology (RISC to ULSAM: 0.491 [0.433, 0.539] for 51 proteins; ULSAM to RISC: 0.369 [0.331, 0.416] for 67 proteins). A randomised LASSO and stability selection algorithm selected only two proteins per cohort (three unique proteins), which improved R2 but to a lesser degree than in standard LASSO models: 0.352 (0.266, 0.439) in RISC and 0.495 (0.404, 0.585) in ULSAM. Reductions in improvements of R2 with randomised LASSO and stability selection were less marked in cross-cohort analyses (RISC to ULSAM R2 0.444 [0.391, 0.497]; ULSAM to RISC R2 0.348 [0.300, 0.396]). Models of proteins alone were as effective as models that included both clinical variables and proteins using either standard or randomised LASSO. The single most consistently selected protein across all analyses and models was IGF-binding protein 2.A plasma proteomic signature identified using a standard LASSO approach improves the cross-sectional estimation of the M value over routine clinical variables. However, a small subset of these proteins identified using a stability selection algorithm affords much of this improvement, especially when considering cross-cohort analyses. Our approach provides opportunities to improve the identification of insulin-resistant individuals at risk of insulin resistance-related adverse health consequences.

    View details for DOI 10.1007/s00125-023-05946-z

    View details for PubMedID 37329449

    View details for PubMedCentralID 5866840

  • Autoimmune alleles at the major histocompatibility locus modify melanoma susceptibility. American journal of human genetics Talwar, J. V., Laub, D., Pagadala, M. S., Castro, A., Lewis, M., Luebeck, G. E., Gorman, B. R., Pan, C., Dong, F. N., Markianos, K., Teerlink, C. C., Lynch, J., Hauger, R., Pyarajan, S., Tsao, P. S., Morris, G. P., Salem, R. M., Thompson, W. K., Curtius, K., Zanetti, M., Carter, H. 2023

    Abstract

    Autoimmunity and cancer represent two different aspects of immune dysfunction. Autoimmunity is characterized by breakdowns in immune self-tolerance, while impaired immune surveillance can allow for tumorigenesis. The class I major histocompatibility complex (MHC-I), which displays derivatives of the cellular peptidome for immune surveillance by CD8+ T cells, serves as a common genetic link between these conditions. As melanoma-specific CD8+ T cells have been shown to target melanocyte-specific peptide antigens more often than melanoma-specific antigens, we investigated whether vitiligo- and psoriasis-predisposing MHC-I alleles conferred a melanoma-protective effect. In individuals with cutaneous melanoma from both The Cancer Genome Atlas (n = 451) and an independent validation set (n = 586), MHC-I autoimmune-allele carrier status was significantly associated with a later age of melanoma diagnosis. Furthermore, MHC-I autoimmune-allele carriers were significantly associated with decreased risk of developing melanoma in the Million Veteran Program (OR = 0.962, p = 0.024). Existing melanoma polygenic risk scores (PRSs) did not predict autoimmune-allele carrier status, suggesting these alleles provide orthogonal risk-relevant information. Mechanisms of autoimmune protection were neither associated with improved melanoma-driver mutation association nor improved gene-level conserved antigen presentation relative to common alleles. However, autoimmune alleles showed higher affinity relative to common alleles for particular windows of melanocyte-conserved antigens and loss of heterozygosity of autoimmune alleles caused the greatest reduction in presentation for several conserved antigens across individuals with loss of HLA alleles. Overall, this study presents evidence that MHC-I autoimmune-risk alleles modulate melanoma risk unaccounted for by current PRSs.

    View details for DOI 10.1016/j.ajhg.2023.05.013

    View details for PubMedID 37339630

  • Genome-wide association study of thoracic aortic aneurysm and dissection in the Million Veteran Program. Nature genetics Klarin, D., Devineni, P., Sendamarai, A. K., Angueira, A. R., Graham, S. E., Shen, Y. H., Levin, M. G., Pirruccello, J. P., Surakka, I., Karnam, P. R., Roychowdhury, T., Li, Y., Wang, M., Aragam, K. G., Paruchuri, K., Zuber, V., Shakt, G. E., Tsao, N. L., Judy, R. L., Vy, H. M., Verma, S. S., Rader, D. J., Do, R., Bavaria, J. E., Nadkarni, G. N., Ritchie, M. D., Burgess, S., Guo, D. C., Ellinor, P. T., LeMaire, S. A., Milewicz, D. M., Willer, C. J., Natarajan, P., Tsao, P. S., Pyarajan, S., Damrauer, S. M. 2023

    Abstract

    The current understanding of the genetic determinants of thoracic aortic aneurysms and dissections (TAAD) has largely been informed through studies of rare, Mendelian forms of disease. Here, we conducted a genome-wide association study (GWAS) of TAAD, testing ~25 million DNA sequence variants in 8,626 participants with and 453,043 participants without TAAD in the Million Veteran Program, with replication in an independent sample of 4,459 individuals with and 512,463 without TAAD from six cohorts. We identified 21 TAAD risk loci, 17 of which have not been previously reported. We leverage multiple downstream analytic methods to identify causal TAAD risk genes and cell types and provide human genetic evidence that TAAD is a non-atherosclerotic aortic disorder distinct from other forms of vascular disease. Our results demonstrate that the genetic architecture of TAAD mirrors that of other complex traits and that it is not solely inherited through protein-altering variants of large effect size.

    View details for DOI 10.1038/s41588-023-01420-z

    View details for PubMedID 37308786

    View details for PubMedCentralID 3244938

  • Genome-Wide Association Study of CKD Progression. Journal of the American Society of Nephrology : JASN Robinson-Cohen, C., Triozzi, J. L., Rowan, B., He, J., Chen, H. C., Zheng, N. S., Wei, W. Q., Wilson, O. D., Hellwege, J. N., Tsao, P. S., Gaziano, J. M., Bick, A., Matheny, M. E., Chung, C. P., Lipworth, L., Siew, E. D., Ikizler, T. A., Tao, R., Hung, A. M. 2023

    Abstract

    Rapid progression of CKD is associated with poor clinical outcomes. Despite extensive study of the genetics of cross-sectional eGFR, only a few loci associated with eGFR decline over time have been identified.We performed a meta-analysis of genome-wide association studies of eGFR decline among 116,870 participants with CKD-defined by two outpatient eGFR measurements of <60 ml/min per 1.73 m 2 , obtained 90-365 days apart-from the Million Veteran Program and Vanderbilt University Medical Center's DNA biobank. The primary outcome was the annualized relative slope in outpatient eGFR. Analyses were stratified by ethnicity and diabetes status and meta-analyzed thereafter.In cross-ancestry meta-analysis, the strongest association was rs77924615, near UMOD / PDILT ; each copy of the G allele was associated with a 0.30%/yr faster eGFR decline ( P = 4.9×10 -27 ). We also observed an association within BICC1 (rs11592748), where every additional minor allele was associated with a 0.13%/yr slower eGFR decline ( P = 5.6×10 -9 ). Among participants without diabetes, the strongest association was the UMOD/PDILT variant rs36060036, associated with a 0.27%/yr faster eGFR decline per copy of the C allele ( P = 1.9×10 -17 ). Among Black participants, a significantly faster eGFR decline was associated with variant rs16996674 near APOL1 (R 2 =0.29 with the G1 high-risk genotype); among Black participants with diabetes, lead variant rs11624911 near HEATR4 also was associated with a significantly faster eGFR decline. We also nominally replicated loci with known associations with eGFR decline, near PRKAG2, FGF5, and C15ORF54.Three loci were significantly associated with longitudinal eGFR change at genome-wide significance. These findings help characterize molecular mechanisms of eGFR decline and may contribute to the development of new therapeutic approaches for progressive CKD.

    View details for DOI 10.1681/ASN.0000000000000170

    View details for PubMedID 37261792

  • Author Correction: The power of genetic diversity in genome-wide association studies of lipids. Nature Graham, S. E., Clarke, S. L., Wu, K. H., Kanoni, S., Zajac, G. J., Ramdas, S., Surakka, I., Ntalla, I., Vedantam, S., Winkler, T. W., Locke, A. E., Marouli, E., Hwang, M. Y., Han, S., Narita, A., Choudhury, A., Bentley, A. R., Ekoru, K., Verma, A., Trivedi, B., Martin, H. C., Hunt, K. A., Hui, Q., Klarin, D., Zhu, X., Thorleifsson, G., Helgadottir, A., Gudbjartsson, D. F., Holm, H., Olafsson, I., Akiyama, M., Sakaue, S., Terao, C., Kanai, M., Zhou, W., Brumpton, B. M., Rasheed, H., Ruotsalainen, S. E., Havulinna, A. S., Veturi, Y., Feng, Q., Rosenthal, E. A., Lingren, T., Pacheco, J. A., Pendergrass, S. A., Haessler, J., Giulianini, F., Bradford, Y., Miller, J. E., Campbell, A., Lin, K., Millwood, I. Y., Hindy, G., Rasheed, A., Faul, J. D., Zhao, W., Weir, D. R., Turman, C., Huang, H., Graff, M., Mahajan, A., Brown, M. R., Zhang, W., Yu, K., Schmidt, E. M., Pandit, A., Gustafsson, S., Yin, X., Luan, J., Zhao, J. H., Matsuda, F., Jang, H. M., Yoon, K., Medina-Gomez, C., Pitsillides, A., Hottenga, J. J., Willemsen, G., Wood, A. R., Ji, Y., Gao, Z., Haworth, S., Mitchell, R. E., Chai, J. F., Aadahl, M., Yao, J., Manichaikul, A., Warren, H. R., Ramirez, J., Bork-Jensen, J., Kårhus, L. L., Goel, A., Sabater-Lleal, M., Noordam, R., Sidore, C., Fiorillo, E., McDaid, A. F., Marques-Vidal, P., Wielscher, M., Trompet, S., Sattar, N., Møllehave, L. T., Thuesen, B. H., Munz, M., Zeng, L., Huang, J., Yang, B., Poveda, A., Kurbasic, A., Lamina, C., Forer, L., Scholz, M., Galesloot, T. E., Bradfield, J. P., Daw, E. W., Zmuda, J. M., Mitchell, J. S., Fuchsberger, C., Christensen, H., Brody, J. A., Feitosa, M. F., Wojczynski, M. K., Preuss, M., Mangino, M., Christofidou, P., Verweij, N., Benjamins, J. W., Engmann, J., Kember, R. L., Slieker, R. C., Lo, K. S., Zilhao, N. R., Le, P., Kleber, M. E., Delgado, G. E., Huo, S., Ikeda, D. D., Iha, H., Yang, J., Liu, J., Leonard, H. L., Marten, J., Schmidt, B., Arendt, M., Smyth, L. J., Cañadas-Garre, M., Wang, C., Nakatochi, M., Wong, A., Hutri-Kähönen, N., Sim, X., Xia, R., Huerta-Chagoya, A., Fernandez-Lopez, J. C., Lyssenko, V., Ahmed, M., Jackson, A. U., Yousri, N. A., Irvin, M. R., Oldmeadow, C., Kim, H. N., Ryu, S., Timmers, P. R., Arbeeva, L., Dorajoo, R., Lange, L. A., Chai, X., Prasad, G., Lorés-Motta, L., Pauper, M., Long, J., Li, X., Theusch, E., Takeuchi, F., Spracklen, C. N., Loukola, A., Bollepalli, S., Warner, S. C., Wang, Y. X., Wei, W. B., Nutile, T., Ruggiero, D., Sung, Y. J., Hung, Y. J., Chen, S., Liu, F., Yang, J., Kentistou, K. A., Gorski, M., Brumat, M., Meidtner, K., Bielak, L. F., Smith, J. A., Hebbar, P., Farmaki, A. E., Hofer, E., Lin, M., Xue, C., Zhang, J., Concas, M. P., Vaccargiu, S., van der Most, P. J., Pitkänen, N., Cade, B. E., Lee, J., van der Laan, S. W., Chitrala, K. N., Weiss, S., Zimmermann, M. E., Lee, J. Y., Choi, H. S., Nethander, M., Freitag-Wolf, S., Southam, L., Rayner, N. W., Wang, C. A., Lin, S. Y., Wang, J. S., Couture, C., Lyytikäinen, L. P., Nikus, K., Cuellar-Partida, G., Vestergaard, H., Hildalgo, B., Giannakopoulou, O., Cai, Q., Obura, M. O., van Setten, J., Li, X., Schwander, K., Terzikhan, N., Shin, J. H., Jackson, R. D., Reiner, A. P., Martin, L. W., Chen, Z., Li, L., Highland, H. M., Young, K. L., Kawaguchi, T., Thiery, J., Bis, J. C., Nadkarni, G. N., Launer, L. J., Li, H., Nalls, M. A., Raitakari, O. T., Ichihara, S., Wild, S. H., Nelson, C. P., Campbell, H., Jäger, S., Nabika, T., Al-Mulla, F., Niinikoski, H., Braund, P. S., Kolcic, I., Kovacs, P., Giardoglou, T., Katsuya, T., Bhatti, K. F., de Kleijn, D., de Borst, G. J., Kim, E. K., Adams, H. H., Ikram, M. A., Zhu, X., Asselbergs, F. W., Kraaijeveld, A. O., Beulens, J. W., Shu, X. O., Rallidis, L. S., Pedersen, O., Hansen, T., Mitchell, P., Hewitt, A. W., Kähönen, M., Pérusse, L., Bouchard, C., Tönjes, A., Chen, Y. I., Pennell, C. E., Mori, T. A., Lieb, W., Franke, A., Ohlsson, C., Mellström, D., Cho, Y. S., Lee, H., Yuan, J. M., Koh, W. P., Rhee, S. Y., Woo, J. T., Heid, I. M., Stark, K. J., Völzke, H., Homuth, G., Evans, M. K., Zonderman, A. B., Polasek, O., Pasterkamp, G., Hoefer, I. E., Redline, S., Pahkala, K., Oldehinkel, A. J., Snieder, H., Biino, G., Schmidt, R., Schmidt, H., Chen, Y. E., Bandinelli, S., Dedoussis, G., Thanaraj, T. A., Kardia, S. L., Kato, N., Schulze, M. B., Girotto, G., Jung, B., Böger, C. A., Joshi, P. K., Bennett, D. A., De Jager, P. L., Lu, X., Mamakou, V., Brown, M., Caulfield, M. J., Munroe, P. B., Guo, X., Ciullo, M., Jonas, J. B., Samani, N. J., Kaprio, J., Pajukanta, P., Adair, L. S., Bechayda, S. A., de Silva, H. J., Wickremasinghe, A. R., Krauss, R. M., Wu, J. Y., Zheng, W., den Hollander, A. I., Bharadwaj, D., Correa, A., Wilson, J. G., Lind, L., Heng, C. K., Nelson, A. E., Golightly, Y. M., Wilson, J. F., Penninx, B., Kim, H. L., Attia, J., Scott, R. J., Rao, D. C., Arnett, D. K., Hunt, S. C., Walker, M., Koistinen, H. A., Chandak, G. R., Yajnik, C. S., Mercader, J. M., Tusié-Luna, T., Aguilar-Salinas, C. A., Villalpando, C. G., Orozco, L., Fornage, M., Tai, E. S., van Dam, R. M., Lehtimäki, T., Chaturvedi, N., Yokota, M., Liu, J., Reilly, D. F., McKnight, A. J., Kee, F., Jöckel, K. H., McCarthy, M. I., Palmer, C. N., Vitart, V., Hayward, C., Simonsick, E., van Duijn, C. M., Lu, F., Qu, J., Hishigaki, H., Lin, X., März, W., Parra, E. J., Cruz, M., Gudnason, V., Tardif, J. C., Lettre, G., 't Hart, L. M., Elders, P. J., Damrauer, S. M., Kumari, M., Kivimaki, M., van der Harst, P., Spector, T. D., Loos, R. J., Province, M. A., Psaty, B. M., Brandslund, I., Pramstaller, P. P., Christensen, K., Ripatti, S., Widén, E., Hakonarson, H., Grant, S. F., Kiemeney, L. A., de Graaf, J., Loeffler, M., Kronenberg, F., Gu, D., Erdmann, J., Schunkert, H., Franks, P. W., Linneberg, A., Jukema, J. W., Khera, A. V., Männikkö, M., Jarvelin, M. R., Kutalik, Z., Cucca, F., Mook-Kanamori, D. O., van Dijk, K. W., Watkins, H., Strachan, D. P., Grarup, N., Sever, P., Poulter, N., Rotter, J. I., Dantoft, T. M., Karpe, F., Neville, M. J., Timpson, N. J., Cheng, C. Y., Wong, T. Y., Khor, C. C., Sabanayagam, C., Peters, A., Gieger, C., Hattersley, A. T., Pedersen, N. L., Magnusson, P. K., Boomsma, D. I., de Geus, E. J., Cupples, L. A., van Meurs, J. B., Ghanbari, M., Gordon-Larsen, P., Huang, W., Kim, Y. J., Tabara, Y., Wareham, N. J., Langenberg, C., Zeggini, E., Kuusisto, J., Laakso, M., Ingelsson, E., Abecasis, G., Chambers, J. C., Kooner, J. S., de Vries, P. S., Morrison, A. C., North, K. E., Daviglus, M., Kraft, P., Martin, N. G., Whitfield, J. B., Abbas, S., Saleheen, D., Walters, R. G., Holmes, M. V., Black, C., Smith, B. H., Justice, A. E., Baras, A., Buring, J. E., Ridker, P. M., Chasman, D. I., Kooperberg, C., Wei, W. Q., Jarvik, G. P., Namjou, B., Hayes, M. G., Ritchie, M. D., Jousilahti, P., Salomaa, V., Hveem, K., Åsvold, B. O., Kubo, M., Kamatani, Y., Okada, Y., Murakami, Y., Thorsteinsdottir, U., Stefansson, K., Ho, Y. L., Lynch, J. A., Rader, D. J., Tsao, P. S., Chang, K. M., Cho, K., O'Donnell, C. J., Gaziano, J. M., Wilson, P., Rotimi, C. N., Hazelhurst, S., Ramsay, M., Trembath, R. C., van Heel, D. A., Tamiya, G., Yamamoto, M., Kim, B. J., Mohlke, K. L., Frayling, T. M., Hirschhorn, J. N., Kathiresan, S., Boehnke, M., Natarajan, P., Peloso, G. M., Brown, C. D., Morris, A. P., Assimes, T. L., Deloukas, P., Sun, Y. V., Willer, C. J. 2023

    View details for DOI 10.1038/s41586-023-06194-2

    View details for PubMedID 37237109

  • Genetically proxied glucose-lowering drug target perturbation and risk of cancer: a Mendelian randomisation analysis. Diabetologia Yarmolinsky, J., Bouras, E., Constantinescu, A., Burrows, K., Bull, C. J., Vincent, E. E., Martin, R. M., Dimopoulou, O., Lewis, S. J., Moreno, V., Vujkovic, M., Chang, K. M., Voight, B. F., Tsao, P. S., Gunter, M. J., Hampe, J., Pellatt, A. J., Pharoah, P. D., Schoen, R. E., Gallinger, S., Jenkins, M. A., Pai, R. K., Gill, D., Tsilidis, K. K. 2023

    Abstract

    Epidemiological studies have generated conflicting findings on the relationship between glucose-lowering medication use and cancer risk. Naturally occurring variation in genes encoding glucose-lowering drug targets can be used to investigate the effect of their pharmacological perturbation on cancer risk.We developed genetic instruments for three glucose-lowering drug targets (peroxisome proliferator activated receptor γ [PPARG]; sulfonylurea receptor 1 [ATP binding cassette subfamily C member 8 (ABCC8)]; glucagon-like peptide 1 receptor [GLP1R]) using summary genetic association data from a genome-wide association study of type 2 diabetes in 148,726 cases and 965,732 controls in the Million Veteran Program. Genetic instruments were constructed using cis-acting genome-wide significant (p<5×10-8) SNPs permitted to be in weak linkage disequilibrium (r2<0.20). Summary genetic association estimates for these SNPs were obtained from genome-wide association study (GWAS) consortia for the following cancers: breast (122,977 cases, 105,974 controls); colorectal (58,221 cases, 67,694 controls); prostate (79,148 cases, 61,106 controls); and overall (i.e. site-combined) cancer (27,483 cases, 372,016 controls). Inverse-variance weighted random-effects models adjusting for linkage disequilibrium were employed to estimate causal associations between genetically proxied drug target perturbation and cancer risk. Co-localisation analysis was employed to examine robustness of findings to violations of Mendelian randomisation (MR) assumptions. A Bonferroni correction was employed as a heuristic to define associations from MR analyses as 'strong' and 'weak' evidence.In MR analysis, genetically proxied PPARG perturbation was weakly associated with higher risk of prostate cancer (for PPARG perturbation equivalent to a 1 unit decrease in inverse rank normal transformed HbA1c: OR 1.75 [95% CI 1.07, 2.85], p=0.02). In histological subtype-stratified analyses, genetically proxied PPARG perturbation was weakly associated with lower risk of oestrogen receptor-positive breast cancer (OR 0.57 [95% CI 0.38, 0.85], p=6.45×10-3). In co-localisation analysis, however, there was little evidence of shared causal variants for type 2 diabetes liability and cancer endpoints in the PPARG locus, although these analyses were likely underpowered. There was little evidence to support associations between genetically proxied PPARG perturbation and colorectal or overall cancer risk or between genetically proxied ABCC8 or GLP1R perturbation with risk across cancer endpoints.Our drug target MR analyses did not find consistent evidence to support an association of genetically proxied PPARG, ABCC8 or GLP1R perturbation with breast, colorectal, prostate or overall cancer risk. Further evaluation of these drug targets using alternative molecular epidemiological approaches may help to further corroborate the findings presented in this analysis.Summary genetic association data for select cancer endpoints were obtained from the public domain: breast cancer ( https://bcac.ccge.medschl.cam.ac.uk/bcacdata/ ); and overall prostate cancer ( http://practical.icr.ac.uk/blog/ ). Summary genetic association data for colorectal cancer can be accessed by contacting GECCO (kafdem at fredhutch.org). Summary genetic association data on advanced prostate cancer can be accessed by contacting PRACTICAL (practical at icr.ac.uk). Summary genetic association data on type 2 diabetes from Vujkovic et al (Nat Genet, 2020) can be accessed through dbGAP under accession number phs001672.v3.p1 (pha004945.1 refers to the European-specific summary statistics). UK Biobank data can be accessed by registering with UK Biobank and completing the registration form in the Access Management System (AMS) ( https://www.ukbiobank.ac.uk/enable-your-research/apply-for-access ).

    View details for DOI 10.1007/s00125-023-05925-4

    View details for PubMedID 37171501

    View details for PubMedCentralID 7310804

  • Building the case for mitochondrial transplantation as an anti-aging cardiovascular therapy. Frontiers in cardiovascular medicine Headley, C. A., Tsao, P. S. 2023; 10: 1141124

    Abstract

    Mitochondrial dysfunction is a common denominator in both biological aging and cardiovascular disease (CVD) pathology. Understanding the protagonist role of mitochondria in the respective and independent progressions of CVD and biological aging will unravel the synergistic relationship between biological aging and CVD. Moreover, the successful development and implementation of therapies that can simultaneously benefit mitochondria of multiple cell types, will be transformational in curtailing pathologies and mortality in the elderly, including CVD. Several works have compared the status of mitochondria in vascular endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) in CVD dependent context. However, fewer studies have cataloged the aging-associated changes in vascular mitochondria, independent of CVD. This mini review will focus on the present evidence related to mitochondrial dysfunction in vascular aging independent of CVD. Additionally, we discuss the feasibility of restoring mitochondrial function in the aged cardiovascular system through mitochondrial transfer.

    View details for DOI 10.3389/fcvm.2023.1141124

    View details for PubMedID 37229220

    View details for PubMedCentralID PMC10203246

  • Cardiovascular Disease Risk Assessment Using Traditional Risk Factors and Polygenic Risk Scores in the Million Veteran Program. JAMA cardiology Vassy, J. L., Posner, D. C., Ho, Y., Gagnon, D. R., Galloway, A., Tanukonda, V., Houghton, S. C., Madduri, R. K., McMahon, B. H., Tsao, P. S., Damrauer, S. M., O'Donnell, C. J., Assimes, T. L., Casas, J. P., Gaziano, J. M., Pencina, M. J., Sun, Y. V., Cho, K., Wilson, P. W. 2023

    Abstract

    Importance: Primary prevention of atherosclerotic cardiovascular disease (ASCVD) relies on risk stratification. Genome-wide polygenic risk scores (PRSs) are proposed to improve ASCVD risk estimation.Objective: To determine whether genome-wide PRSs for coronary artery disease (CAD) and acute ischemic stroke improve ASCVD risk estimation with traditional clinical risk factors in an ancestrally diverse midlife population.Design, Setting, and Participants: This was a prognostic analysis of incident events in a retrospectively defined longitudinal cohort conducted from January 1, 2011, to December 31, 2018. Included in the study were adults free of ASCVD and statin naive at baseline from the Million Veteran Program (MVP), a mega biobank with genetic, survey, and electronic health record data from a large US health care system. Data were analyzed from March 15, 2021, to January 5, 2023.Exposures: PRSs for CAD and ischemic stroke derived from cohorts of largely European descent and risk factors, including age, sex, systolic blood pressure, total cholesterol, high-density lipoprotein (HDL) cholesterol, smoking, and diabetes status.Main Outcomes and Measures: Incident nonfatal myocardial infarction (MI), ischemic stroke, ASCVD death, and composite ASCVD events.Results: A total of 79 151 participants (mean [SD] age, 57.8 [13.7] years; 68 503 male [86.5%]) were included in the study. The cohort included participants from the following harmonized genetic ancestry and race and ethnicity categories: 18 505 non-Hispanic Black (23.4%), 6785 Hispanic (8.6%), and 53 861 non-Hispanic White (68.0%) with a median (5th-95th percentile) follow-up of 4.3 (0.7-6.9) years. From 2011 to 2018, 3186 MIs (4.0%), 1933 ischemic strokes (2.4%), 867 ASCVD deaths (1.1%), and 5485 composite ASCVD events (6.9%) were observed. CAD PRS was associated with incident MI in non-Hispanic Black (hazard ratio [HR], 1.10; 95% CI, 1.02-1.19), Hispanic (HR, 1.26; 95% CI, 1.09-1.46), and non-Hispanic White (HR, 1.23; 95% CI, 1.18-1.29) participants. Stroke PRS was associated with incident stroke in non-Hispanic White participants (HR, 1.15; 95% CI, 1.08-1.21). A combined CAD plus stroke PRS was associated with ASCVD deaths among non-Hispanic Black (HR, 1.19; 95% CI, 1.03-1.17) and non-Hispanic (HR, 1.11; 95% CI, 1.03-1.21) participants. The combined PRS was also associated with composite ASCVD across all ancestry groups but greater among non-Hispanic White (HR, 1.20; 95% CI, 1.16-1.24) than non-Hispanic Black (HR, 1.11; 95% CI, 1.05-1.17) and Hispanic (HR, 1.12; 95% CI, 1.00-1.25) participants. Net reclassification improvement from adding PRS to a traditional risk model was modest for the intermediate risk group for composite CVD among men (5-year risk >3.75%, 0.38%; 95% CI, 0.07%-0.68%), among women, (6.79%; 95% CI, 3.01%-10.58%), for age older than 55 years (0.25%; 95% CI, 0.03%-0.47%), and for ages 40 to 55 years (1.61%; 95% CI, -0.07% to 3.30%).Conclusions and Relevance: Study results suggest that PRSs derived predominantly in European samples were statistically significantly associated with ASCVD in the multiancestry midlife and older-age MVP cohort. Overall, modest improvement in discrimination metrics were observed with addition of PRSs to traditional risk factors with greater magnitude in women and younger age groups.

    View details for DOI 10.1001/jamacardio.2023.0857

    View details for PubMedID 37133828

  • Multi-ancestry genome-wide study in >2.5 million individuals reveals heterogeneity in mechanistic pathways of type 2 diabetes and complications. medRxiv : the preprint server for health sciences Suzuki, K., Hatzikotoulas, K., Southam, L., Taylor, H. J., Yin, X., Lorenz, K. M., Mandla, R., Huerta-Chagoya, A., Rayner, N. W., Bocher, O., Arruda, A. n., Sonehara, K., Namba, S., Lee, S. S., Preuss, M. H., Petty, L. E., Schroeder, P., Vanderwerff, B., Kals, M., Bragg, F., Lin, K., Guo, X., Zhang, W., Yao, J., Kim, Y. J., Graff, M., Takeuchi, F., Nano, J., Lamri, A., Nakatochi, M., Moon, S., Scott, R. A., Cook, J. P., Lee, J. J., Pan, I., Taliun, D., Parra, E. J., Chai, J. F., Bielak, L. F., Tabara, Y., Hai, Y., Thorleifsson, G., Grarup, N., Sofer, T., Wuttke, M., Sarnowski, C., Gieger, C., Nousome, D., Trompet, S., Kwak, S. H., Long, J., Sun, M., Tong, L., Chen, W. M., Nongmaithem, S. S., Noordam, R., Lim, V. J., Tam, C. H., Joo, Y. Y., Chen, C. H., Raffield, L. M., Prins, B. P., Nicolas, A., Yanek, L. R., Chen, G., Brody, J. A., Kabagambe, E., An, P., Xiang, A. H., Choi, H. S., Cade, B. E., Tan, J., Broadaway, K. A., Williamson, A., Kamali, Z., Cui, J., Adair, L. S., Adeyemo, A., Aguilar-Salinas, C. A., Ahluwalia, T. S., Anand, S. S., Bertoni, A., Bork-Jensen, J., Brandslund, I., Buchanan, T. A., Burant, C. F., Butterworth, A. S., Canouil, M., Chan, J. C., Chang, L. C., Chee, M. L., Chen, J., Chen, S. H., Chen, Y. T., Chen, Z., Chuang, L. M., Cushman, M., Danesh, J., Das, S. K., de Silva, H. J., Dedoussis, G., Dimitrov, L., Doumatey, A. P., Du, S., Duan, Q., Eckardt, K. U., Emery, L. S., Evans, D. S., Evans, M. K., Fischer, K., Floyd, J. S., Ford, I., Franco, O. H., Frayling, T. M., Freedman, B. I., Genter, P., Gerstein, H. C., Giedraitis, V., González-Villalpando, C., González-Villalpando, M. E., Gordon-Larsen, P., Gross, M., Guare, L. A., Hackinger, S., Han, S., Hattersley, A. T., Herder, C., Horikoshi, M., Howard, A. G., Hsueh, W., Huang, M., Huang, W., Hung, Y. J., Hwang, M. Y., Hwu, C. M., Ichihara, S., Ikram, M. A., Ingelsson, M., Islam, M. T., Isono, M., Jang, H. M., Jasmine, F., Jiang, G., Jonas, J. B., Jørgensen, T., Kandeel, F. R., Kasturiratne, A., Katsuya, T., Kaur, V., Kawaguchi, T., Keaton, J. M., Kho, A. N., Khor, C. C., Kibriya, M. G., Kim, D. H., Kronenberg, F., Kuusisto, J., Läll, K., Lange, L. A., Lee, K. M., Lee, M. S., Lee, N. R., Leong, A., Li, L., Li, Y., Li-Gao, R., Lithgart, S., Lindgren, C. M., Linneberg, A., Liu, C. T., Liu, J., Locke, A. E., Louie, T., Luan, J., Luk, A. O., Luo, X., Lv, J., Lynch, J. A., Lyssenko, V., Maeda, S., Mamakou, V., Mansuri, S. R., Matsuda, K., Meitinger, T., Metspalu, A., Mo, H., Morris, A. D., Nadler, J. L., Nalls, M. A., Nayak, U., Ntalla, I., Okada, Y., Orozco, L., Patel, S. R., Patil, S., Pei, P., Pereira, M. A., Peters, A., Pirie, F. J., Polikowsky, H. G., Porneala, B., Prasad, G., Rasmussen-Torvik, L. J., Reiner, A. P., Roden, M., Rohde, R., Roll, K., Sabanayagam, C., Sandow, K., Sankareswaran, A., Sattar, N., Schönherr, S., Shahriar, M., Shen, B., Shi, J., Shin, D. M., Shojima, N., Smith, J. A., So, W. Y., Stančáková, A., Steinthorsdottir, V., Stilp, A. M., Strauch, K., Taylor, K. D., Thorand, B., Thorsteinsdottir, U., Tomlinson, B., Tran, T. C., Tsai, F. J., Tuomilehto, J., Tusie-Luna, T., Udler, M. S., Valladares-Salgado, A., van Dam, R. M., van Klinken, J. B., Varma, R., Wacher-Rodarte, N., Wheeler, E., Wickremasinghe, A. R., van Dijk, K. W., Witte, D. R., Yajnik, C. S., Yamamoto, K., Yamamoto, K., Yoon, K., Yu, C., Yuan, J. M., Yusuf, S., Zawistowski, M., Zhang, L., Zheng, W., Raffel, L. J., Igase, M., Ipp, E., Redline, S., Cho, Y. S., Lind, L., Province, M. A., Fornage, M., Hanis, C. L., Ingelsson, E., Zonderman, A. B., Psaty, B. M., Wang, Y. X., Rotimi, C. N., Becker, D. M., Matsuda, F., Liu, Y., Yokota, M., Kardia, S. L., Peyser, P. A., Pankow, J. S., Engert, J. C., Bonnefond, A., Froguel, P., Wilson, J. G., Sheu, W. H., Wu, J. Y., Hayes, M. G., Ma, R. C., Wong, T. Y., Mook-Kanamori, D. O., Tuomi, T., Chandak, G. R., Collins, F. S., Bharadwaj, D., Paré, G., Sale, M. M., Ahsan, H., Motala, A. A., Shu, X. O., Park, K. S., Jukema, J. W., Cruz, M., Chen, Y. I., Rich, S. S., McKean-Cowdin, R., Grallert, H., Cheng, C. Y., Ghanbari, M., Tai, E. S., Dupuis, J., Kato, N., Laakso, M., Köttgen, A., Koh, W. P., Bowden, D. W., Palmer, C. N., Kooner, J. S., Kooperberg, C., Liu, S., North, K. E., Saleheen, D., Hansen, T., Pedersen, O., Wareham, N. J., Lee, J., Kim, B. J., Millwood, I. Y., Walters, R. G., Stefansson, K., Goodarzi, M. O., Mohlke, K. L., Langenberg, C., Haiman, C. A., Loos, R. J., Florez, J. C., Rader, D. J., Ritchie, M. D., Zöllner, S., Mägi, R., Denny, J. C., Yamauchi, T., Kadowaki, T., Chambers, J. C., Ng, M. C., Sim, X., Below, J. E., Tsao, P. S., Chang, K. M., McCarthy, M. I., Meigs, J. B., Mahajan, A., Spracklen, C. N., Mercader, J. M., Boehnke, M., Rotter, J. I., Vujkovic, M., Voight, B. F., Morris, A. P., Zeggini, E. 2023

    Abstract

    Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes. To characterise the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study (GWAS) data from 2,535,601 individuals (39.7% non-European ancestry), including 428,452 T2D cases. We identify 1,289 independent association signals at genome-wide significance (P<5×10-8) that map to 611 loci, of which 145 loci are previously unreported. We define eight non-overlapping clusters of T2D signals characterised by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial, and enteroendocrine cells. We build cluster-specific partitioned genetic risk scores (GRS) in an additional 137,559 individuals of diverse ancestry, including 10,159 T2D cases, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned GRS are more strongly associated with coronary artery disease and end-stage diabetic nephropathy than an overall T2D GRS across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings demonstrate the value of integrating multi-ancestry GWAS with single-cell epigenomics to disentangle the aetiological heterogeneity driving the development and progression of T2D, which may offer a route to optimise global access to genetically-informed diabetes care.

    View details for DOI 10.1101/2023.03.31.23287839

    View details for PubMedID 37034649

    View details for PubMedCentralID PMC10081410

  • Overview of Efforts to Increase Women Enrollment in the Veterans Affairs Million Veteran Program. Health equity Whitbourne, S. B., Li, Y., Brewer, J. V., Deen, J., Gutierrez, C., Murphy, S. A., Lord, E., Yan, J., Nguyen, X. T., Tsao, P. S., Gaziano, J. M., Muralidhar, S. 2023; 7 (1): 324-332

    Abstract

    Background: Ensuring enhanced delivery of care to women Veterans is a top Veterans Affairs (VA) priority; however, women are historically underrepresented in research that informs evidence-based health care. A primary barrier to women's participation is the inability to engage with research in person due to a number of documented challenges. The VA Million Veteran Program (MVP) is committed to increasing access for women Veterans to participate in research, thereby better understanding conditions specific to this population and how disease manifests differently in women compared to men. The goal of this work is to describe the results of the MVP Women's Campaign, an effort designed to increase outreach to and awareness of remote enrollment options for women Veterans.Materials and Methods: The MVP Women's Campaign launched two phases between March 2021 and April 2022: the Multimedia Phase leveraged a variety of strategic multichannel communication tactics and the Email Phase focused on direct email communication to women Veterans. The effect of the Multimedia Phase was determined using t-tests and chi-square tests, as well as logistic regression models to compare demographic subgroups. The Email Phase was evaluated using comparisons of the enrollment rate across demographic groups through a multivariate adjusted logistic regression model.Results: Overall, 4694 women Veterans enrolled during the MVP Women's Campaign (54% during the Multimedia Phase and 46% during the Email Phase). For the Multimedia Phase, the percentage of older women online enrollees increased, along with women from the southwest and western regions of the United States. Differences for women Veteran online enrollment across different ethnicity and race groups were not observed. During the Email Phase, the enrollment rate increased with age. Compared to White women Veterans, Blacks, Asians, and Native Americans were significantly less likely to enroll while Veterans with multiple races were more likely to enroll.Conclusion: The MVP Women's Campaign is the first large-scale outreach effort focusing on recruitment of women Veterans into MVP. The combination of print and digital outreach tactics and direct email recruitment resulted in over a fivefold increase in women Veteran enrollees during a 7-month period. Attention to messaging and communication channels, combined with a better understanding of effective recruitment methods for certain Veteran populations, allows MVP the opportunity to advance health and health care not only for women Veterans, but beyond. Lessons learned will be applied to increase other populations in MVP such as Blacks, Hispanics, Asians, Native Americans, younger Veterans, and Veterans with certain health conditions.

    View details for DOI 10.1089/heq.2023.0006

    View details for PubMedID 37284530

  • IS IT POSSIBLE TO ACCELERATE SENESCENCE IN THE VASCULAR ENDOTHELIAL CELL BY MODULATING SEVERAL MICRORNAS? Toyama, K., Spin, J. M., Tsao, P. S., Mogi, M. LIPPINCOTT WILLIAMS & WILKINS. 2023: E171
  • Genomics and phenomics of body mass index reveals a complex disease network. Nature communications Huang, J., Huffman, J. E., Huang, Y., Do Valle, Í., Assimes, T. L., Raghavan, S., Voight, B. F., Liu, C., Barabási, A. L., Huang, R. D., Hui, Q., Nguyen, X. T., Ho, Y. L., Djousse, L., Lynch, J. A., Vujkovic, M., Tcheandjieu, C., Tang, H., Damrauer, S. M., Reaven, P. D., Miller, D., Phillips, L. S., Ng, M. C., Graff, M., Haiman, C. A., Loos, R. J., North, K. E., Yengo, L., Smith, G. D., Saleheen, D., Gaziano, J. M., Rader, D. J., Tsao, P. S., Cho, K., Chang, K. M., Wilson, P. W., Sun, Y. V., O'Donnell, C. J. 2022; 13 (1): 7973

    Abstract

    Elevated body mass index (BMI) is heritable and associated with many health conditions that impact morbidity and mortality. The study of the genetic association of BMI across a broad range of common disease conditions offers the opportunity to extend current knowledge regarding the breadth and depth of adiposity-related diseases. We identify 906 (364 novel) and 41 (6 novel) genome-wide significant loci for BMI among participants of European (N~1.1 million) and African (N~100,000) ancestry, respectively. Using a BMI genetic risk score including 2446 variants, 316 diagnoses are associated in the Million Veteran Program, with 96.5% showing increased risk. A co-morbidity network analysis reveals seven disease communities containing multiple interconnected diseases associated with BMI as well as extensive connections across communities. Mendelian randomization analysis confirms numerous phenotypes across a breadth of organ systems, including conditions of the circulatory (heart failure, ischemic heart disease, atrial fibrillation), genitourinary (chronic renal failure), respiratory (respiratory failure, asthma), musculoskeletal and dermatologic systems that are deeply interconnected within and across the disease communities. This work shows that the complex genetic architecture of BMI associates with a broad range of major health conditions, supporting the need for comprehensive approaches to prevent and treat obesity.

    View details for DOI 10.1038/s41467-022-35553-2

    View details for PubMedID 36581621

  • Implicating genes, pleiotropy, and sexual dimorphism at blood lipid loci through multi-ancestry meta-analysis. Genome biology Kanoni, S., Graham, S. E., Wang, Y., Surakka, I., Ramdas, S., Zhu, X., Clarke, S. L., Bhatti, K. F., Vedantam, S., Winkler, T. W., Locke, A. E., Marouli, E., Zajac, G. J., Wu, K. H., Ntalla, I., Hui, Q., Klarin, D., Hilliard, A. T., Wang, Z., Xue, C., Thorleifsson, G., Helgadottir, A., Gudbjartsson, D. F., Holm, H., Olafsson, I., Hwang, M. Y., Han, S., Akiyama, M., Sakaue, S., Terao, C., Kanai, M., Zhou, W., Brumpton, B. M., Rasheed, H., Havulinna, A. S., Veturi, Y., Pacheco, J. A., Rosenthal, E. A., Lingren, T., Feng, Q., Kullo, I. J., Narita, A., Takayama, J., Martin, H. C., Hunt, K. A., Trivedi, B., Haessler, J., Giulianini, F., Bradford, Y., Miller, J. E., Campbell, A., Lin, K., Millwood, I. Y., Rasheed, A., Hindy, G., Faul, J. D., Zhao, W., Weir, D. R., Turman, C., Huang, H., Graff, M., Choudhury, A., Sengupta, D., Mahajan, A., Brown, M. R., Zhang, W., Yu, K., Schmidt, E. M., Pandit, A., Gustafsson, S., Yin, X., Luan, J., Zhao, J. H., Matsuda, F., Jang, H. M., Yoon, K., Medina-Gomez, C., Pitsillides, A., Hottenga, J. J., Wood, A. R., Ji, Y., Gao, Z., Haworth, S., Yousri, N. A., Mitchell, R. E., Chai, J. F., Aadahl, M., Bjerregaard, A. A., Yao, J., Manichaikul, A., Hwu, C. M., Hung, Y. J., Warren, H. R., Ramirez, J., Bork-Jensen, J., Kårhus, L. L., Goel, A., Sabater-Lleal, M., Noordam, R., Mauro, P., Matteo, F., McDaid, A. F., Marques-Vidal, P., Wielscher, M., Trompet, S., Sattar, N., Møllehave, L. T., Munz, M., Zeng, L., Huang, J., Yang, B., Poveda, A., Kurbasic, A., Lamina, C., Forer, L., Scholz, M., Galesloot, T. E., Bradfield, J. P., Ruotsalainen, S. E., Daw, E., Zmuda, J. M., Mitchell, J. S., Fuchsberger, C., Christensen, H., Brody, J. A., Vazquez-Moreno, M., Feitosa, M. F., Wojczynski, M. K., Wang, Z., Preuss, M. H., Mangino, M., Christofidou, P., Verweij, N., Benjamins, J. W., Engmann, J., Tsao, N. L., Verma, A., Slieker, R. C., Lo, K. S., Zilhao, N. R., Le, P., Kleber, M. E., Delgado, G. E., Huo, S., Ikeda, D. D., Iha, H., Yang, J., Liu, J., Demirkan, A., Leonard, H. L., Marten, J., Frank, M., Schmidt, B., Smyth, L. J., Cañadas-Garre, M., Wang, C., Nakatochi, M., Wong, A., Hutri-Kähönen, N., Sim, X., Xia, R., Huerta-Chagoya, A., Fernandez-Lopez, J. C., Lyssenko, V., Nongmaithem, S. S., Bayyana, S., Stringham, H. M., Irvin, M. R., Oldmeadow, C., Kim, H. N., Ryu, S., Timmers, P. R., Arbeeva, L., Dorajoo, R., Lange, L. A., Prasad, G., Lorés-Motta, L., Pauper, M., Long, J., Li, X., Theusch, E., Takeuchi, F., Spracklen, C. N., Loukola, A., Bollepalli, S., Warner, S. C., Wang, Y. X., Wei, W. B., Nutile, T., Ruggiero, D., Sung, Y. J., Chen, S., Liu, F., Yang, J., Kentistou, K. A., Banas, B., Nardone, G. G., Meidtner, K., Bielak, L. F., Smith, J. A., Hebbar, P., Farmaki, A. E., Hofer, E., Lin, M., Concas, M. P., Vaccargiu, S., van der Most, P. J., Pitkänen, N., Cade, B. E., van der Laan, S. W., Chitrala, K. N., Weiss, S., Bentley, A. R., Doumatey, A. P., Adeyemo, A. A., Lee, J. Y., Petersen, E. R., Nielsen, A. A., Choi, H. S., Nethander, M., Freitag-Wolf, S., Southam, L., Rayner, N. W., Wang, C. A., Lin, S. Y., Wang, J. S., Couture, C., Lyytikäinen, L. P., Nikus, K., Cuellar-Partida, G., Vestergaard, H., Hidalgo, B., Giannakopoulou, O., Cai, Q., Obura, M. O., van Setten, J., Li, X., Liang, J., Tang, H., Terzikhan, N., Shin, J. H., Jackson, R. D., Reiner, A. P., Martin, L. W., Chen, Z., Li, L., Kawaguchi, T., Thiery, J., Bis, J. C., Launer, L. J., Li, H., Nalls, M. A., Raitakari, O. T., Ichihara, S., Wild, S. H., Nelson, C. P., Campbell, H., Jäger, S., Nabika, T., Al-Mulla, F., Niinikoski, H., Braund, P. S., Kolcic, I., Kovacs, P., Giardoglou, T., Katsuya, T., de Kleijn, D., de Borst, G. J., Kim, E. K., Adams, H. H., Ikram, M. A., Zhu, X., Asselbergs, F. W., Kraaijeveld, A. O., Beulens, J. W., Shu, X. O., Rallidis, L. S., Pedersen, O., Hansen, T., Mitchell, P., Hewitt, A. W., Kähönen, M., Pérusse, L., Bouchard, C., Tönjes, A., Chen, Y. I., Pennell, C. E., Mori, T. A., Lieb, W., Franke, A., Ohlsson, C., Mellström, D., Cho, Y. S., Lee, H., Yuan, J. M., Koh, W. P., Rhee, S. Y., Woo, J. T., Heid, I. M., Stark, K. J., Zimmermann, M. E., Völzke, H., Homuth, G., Evans, M. K., Zonderman, A. B., Polasek, O., Pasterkamp, G., Hoefer, I. E., Redline, S., Pahkala, K., Oldehinkel, A. J., Snieder, H., Biino, G., Schmidt, R., Schmidt, H., Bandinelli, S., Dedoussis, G., Thanaraj, T. A., Kardia, S. L., Peyser, P. A., Kato, N., Schulze, M. B., Girotto, G., Böger, C. A., Jung, B., Joshi, P. K., Bennett, D. A., De Jager, P. L., Lu, X., Mamakou, V., Brown, M., Caulfield, M. J., Munroe, P. B., Guo, X., Ciullo, M., Jonas, J. B., Samani, N. J., Kaprio, J., Pajukanta, P., Tusié-Luna, T., Aguilar-Salinas, C. A., Adair, L. S., Bechayda, S. A., de Silva, H. J., Wickremasinghe, A. R., Krauss, R. M., Wu, J. Y., Zheng, W., Hollander, A. I., Bharadwaj, D., Correa, A., Wilson, J. G., Lind, L., Heng, C. K., Nelson, A. E., Golightly, Y. M., Wilson, J. F., Penninx, B., Kim, H. L., Attia, J., Scott, R. J., Rao, D. C., Arnett, D. K., Hunt, S. C., Walker, M., Koistinen, H. A., Chandak, G. R., Mercader, J. M., Costanzo, M. C., Jang, D., Burtt, N. P., Villalpando, C. G., Orozco, L., Fornage, M., Tai, E., van Dam, R. M., Lehtimäki, T., Chaturvedi, N., Yokota, M., Liu, J., Reilly, D. F., McKnight, A. J., Kee, F., Jöckel, K. H., McCarthy, M. I., Palmer, C. N., Vitart, V., Hayward, C., Simonsick, E., van Duijn, C. M., Jin, Z. B., Qu, J., Hishigaki, H., Lin, X., März, W., Gudnason, V., Tardif, J. C., Lettre, G., Hart, L. M., Elders, P. J., Damrauer, S. M., Kumari, M., Kivimaki, M., van der Harst, P., Spector, T. D., Loos, R. J., Province, M. A., Parra, E. J., Cruz, M., Psaty, B. M., Brandslund, I., Pramstaller, P. P., Rotimi, C. N., Christensen, K., Ripatti, S., Widén, E., Hakonarson, H., Grant, S. F., Kiemeney, L. A., de Graaf, J., Loeffler, M., Kronenberg, F., Gu, D., Erdmann, J., Schunkert, H., Franks, P. W., Linneberg, A., Jukema, J. W., Khera, A. V., Männikkö, M., Jarvelin, M. R., Kutalik, Z., Francesco, C., Mook-Kanamori, D. O., van Dijk, K. W., Watkins, H., Strachan, D. P., Grarup, N., Sever, P., Poulter, N., Chuang, L. M., Rotter, J. I., Dantoft, T. M., Karpe, F., Neville, M. J., Timpson, N. J., Cheng, C. Y., Wong, T. Y., Khor, C. C., Li, H., Sabanayagam, C., Peters, A., Gieger, C., Hattersley, A. T., Pedersen, N. L., Magnusson, P. K., Boomsma, D. I., Willemsen, A. H., Cupples, L., van Meurs, J. B., Ghanbari, M., Gordon-Larsen, P., Huang, W., Kim, Y. J., Tabara, Y., Wareham, N. J., Langenberg, C., Zeggini, E., Kuusisto, J., Laakso, M., Ingelsson, E., Abecasis, G., Chambers, J. C., Kooner, J. S., de Vries, P. S., Morrison, A. C., Hazelhurst, S., Ramsay, M., North, K. E., Daviglus, M., Kraft, P., Martin, N. G., Whitfield, J. B., Abbas, S., Saleheen, D., Walters, R. G., Holmes, M. V., Black, C., Smith, B. H., Baras, A., Justice, A. E., Buring, J. E., Ridker, P. M., Chasman, D. I., Kooperberg, C., Tamiya, G., Yamamoto, M., van Heel, D. A., Trembath, R. C., Wei, W. Q., Jarvik, G. P., Namjou, B., Hayes, M. G., Ritchie, M. D., Jousilahti, P., Salomaa, V., Hveem, K., Åsvold, B. O., Kubo, M., Kamatani, Y., Okada, Y., Murakami, Y., Kim, B. J., Thorsteinsdottir, U., Stefansson, K., Zhang, J., Chen, Y., Ho, Y. L., Lynch, J. A., Rader, D. J., Tsao, P. S., Chang, K. M., Cho, K., O'Donnell, C. J., Gaziano, J. M., Wilson, P. W., Frayling, T. M., Hirschhorn, J. N., Kathiresan, S., Mohlke, K. L., Sun, Y. V., Morris, A. P., Boehnke, M., Brown, C. D., Natarajan, P., Deloukas, P., Willer, C. J., Assimes, T. L., Peloso, G. M. 2022; 23 (1): 268

    Abstract

    Genetic variants within nearly 1000 loci are known to contribute to modulation of blood lipid levels. However, the biological pathways underlying these associations are frequently unknown, limiting understanding of these findings and hindering downstream translational efforts such as drug target discovery.To expand our understanding of the underlying biological pathways and mechanisms controlling blood lipid levels, we leverage a large multi-ancestry meta-analysis (N = 1,654,960) of blood lipids to prioritize putative causal genes for 2286 lipid associations using six gene prediction approaches. Using phenome-wide association (PheWAS) scans, we identify relationships of genetically predicted lipid levels to other diseases and conditions. We confirm known pleiotropic associations with cardiovascular phenotypes and determine novel associations, notably with cholelithiasis risk. We perform sex-stratified GWAS meta-analysis of lipid levels and show that 3-5% of autosomal lipid-associated loci demonstrate sex-biased effects. Finally, we report 21 novel lipid loci identified on the X chromosome. Many of the sex-biased autosomal and X chromosome lipid loci show pleiotropic associations with sex hormones, emphasizing the role of hormone regulation in lipid metabolism.Taken together, our findings provide insights into the biological mechanisms through which associated variants lead to altered lipid levels and potentially cardiovascular disease risk.

    View details for DOI 10.1186/s13059-022-02837-1

    View details for PubMedID 36575460

    View details for PubMedCentralID PMC9793579

  • Linking single nucleotide polymorphisms to signaling blueprints in abdominal aortic aneurysms. Scientific reports Lim, C., Pratama, M. Y., Rivera, C., Silvestro, M., Tsao, P. S., Maegdefessel, L., Gallagher, K. A., Maldonado, T., Ramkhelawon, B. 2022; 12 (1): 20990

    Abstract

    Abdominal aortic aneurysms (AAA) is a multifactorial complex disease with life-threatening consequences. While Genome-wide association studies (GWAS) have revealed several single nucleotide polymorphisms (SNPs) located in the genome of individuals with AAA, the link between SNPs with the associated pathological signals, the influence of risk factors on their distribution and their combined analysis is not fully understood. We integrated 86 AAA SNPs from GWAS and clinical cohorts from the literature to determine their phenotypical vulnerabilities and association with AAA risk factors. The SNPs were annotated using snpXplorer AnnotateMe tool to identify their chromosomal position, minor allele frequency, CADD (Combined Annotation Dependent Depletion), annotation-based pathogenicity score, variant consequence, and their associated gene. Gene enrichment analysis was performed using Gene Ontology and clustered using REVIGO. The plug-in GeneMANIA in Cytoscape was applied to identify network integration with associated genes and functions. 15 SNPs affecting 20 genes with a CADD score above ten were identified. AAA SNPs were predominantly located on chromosome 3 and 9. Stop-gained rs5516 SNP obtained high frequency in AAA and associated with proinflammatory and vascular remodeling phenotypes. SNPs presence positively correlated with hypertension, dyslipidemia and smoking history. GO showed that AAA SNPs and their associated genes could regulate lipid metabolism, extracellular matrix organization, smooth muscle cell proliferation, and oxidative stress, suggesting that part of these AAA traits could stem from genetic abnormalities. We show a library of inborn SNPs and associated genes that manifest in AAA. We uncover their pathological signaling trajectories that likely fuel AAA development.

    View details for DOI 10.1038/s41598-022-25144-y

    View details for PubMedID 36470918

  • Fibromuscular Dysplasia and Abdominal Aortic Aneurysms Are Dimorphic Sex-Specific Diseases With Shared Complex Genetic Architecture. Circulation. Genomic and precision medicine Katz, A. E., Yang, M., Levin, M. G., Tcheandjieu, C., Mathis, M., Hunker, K., Blackburn, S., Eliason, J. L., Coleman, D. M., Fendrikova-Mahlay, N., Gornik, H. L., Karmakar, M., Hill, H., Xu, C., Zawistowski, M., Brummett, C. M., Zoellner, S., Zhou, X., O'Donnell, C., Douglas, J. A., Assimes, T. L., Tsao, P. S., Li, J. Z., Damrauer, S. M., Stanley, J. C., Ganesh, S. K., VA Million Veteran Program, Gaziano, J. M., Muralidhar, S., Ramoni, R., Beckham, J., Chang, K., Breeling, J., Huang, G., Casas, J. P., Muralidhar, S., Moser, J., Whitbourne, S. B., Brewer, J. V., Aslan, M., Connor, T., Argyres, D. P., Gaziano, J. M., Stephens, B., Brophy, M. T., Humphries, D. E., Selva, L. E., Do, N., Shayan, S. A., Cho, K., Churby, L., Pyarajan, S., Cho, K., DuVall, S. L., Pyarajan, S., Hauser, E., Sun, Y., Zhao, H., Wilson, P., McArdle, R., Dellitalia, L., Mattocks, K., Harley, J., Whittle, J., Jacono, F., Beckham, J., Wells, J., Gutierrez, S., Gibson, G., Hammer, K., Kaminsky, L., Villareal, G., Kinlay, S., Xu, J., Hamner, M., Mathew, R., Bhushan, S., Iruvanti, P., Godschalk, M., Ballas, Z., Ivins, D., Mastorides, S., Moorman, J., Gappy, S., Klein, J., Ratcliffe, N., Florez, H., Okusaga, O., Murdoch, M., Sriram, P., Yeh, S. S., Tandon, N., Jhala, D., Aguayo, S., Cohen, D., Sharma, S., Liangpunsakul, S., Oursler, K. A., Whooley, M., Ahuja, S., Constans, J., Meyer, P., Greco, J., Rauchman, M., Servatius, R., Gaddy, M., Wallbom, A., Morgan, T., Stapley, T., Sherman, S., Ross, G., Strollo, P. J., Boyko, E., Meyer, L., Gupta, S., Huq, M., Fayad, J., Hung, A., Lichy, J., Hurley, R., Robey, B., Striker, R. 2022: e003496

    Abstract

    BACKGROUND: The risk of arterial diseases may be elevated among family members of individuals having multifocal fibromuscular dysplasia (FMD). We sought to investigate the risk of arterial diseases in families of individuals with FMD.METHODS: Family histories for 73 probands with FMD were obtained, which included an analysis of 463 total first-degree relatives focusing on FMD and related arterial disorders. A polygenic risk score for FMD (PRSFMD) was constructed from prior genome-wide association findings of 584 FMD cases and 7139 controls and evaluated for association with an abdominal aortic aneurysm (AAA) in a cohort of 9693 AAA cases and 294049 controls. A previously published PRSAAA was also assessed among the FMD cases and controls.RESULTS: 9.3% (43) of all first-degree relatives of probands were diagnosed with FMD, aneurysms, and dissections. Aneurysmal disease occurred in 60.5% of affected relatives and 5.6% of all relatives. Among 227 female first-degree relatives of probands, 4.8% (11) had FMD, representing a relative risk (RR)FMD of 1.5 ([95% CI, 0.75-2.8]; P=0.19) compared with the estimated population prevalence of 3.3%, though not of statistical significance. 11% (8 of 72) of FMD proband fathers had AAAs resulting in a RRAAA of 2.3 ([95% CI, 1.12-4.6]; P=0.014) compared with population estimates. The PRSFMD was found to be associated with an AAA (odds ratio, 1.03 [95% CI, 1.01-1.05]; P=2.6*10-3), and the PRSAAA was found to be associated with FMD (odds ratio, 1.53 [95% CI, 1.2-1.9]; P=9.0*10-5) as well.CONCLUSIONS: FMD and AAAs seem to be sex-dimorphic manifestations of a heritable arterial disease with a partially shared complex genetic architecture. Excess risk of having an AAA according to a family history of FMD may justify screening in family members of individuals having FMD.

    View details for DOI 10.1161/CIRCGEN.121.003496

    View details for PubMedID 36374587

  • Mild-to-Moderate Kidney Dysfunction and Cardiovascular Disease: Observational and Mendelian Randomization Analyses. Circulation Gaziano, L., Sun, L., Arnold, M., Bell, S., Cho, K., Kaptoge, S. K., Song, R. J., Burgess, S., Posner, D. C., Mosconi, K., Robinson-Cohen, C., Mason, A., Bolton, T. R., Tao, R., Allara, E., Schubert, P., Chen, L., Staley, J. R., Staplin, N., Altay, S., Amiano, P., Arndt, V., Arnlov, J., Barr, E. L., Bjorkelund, C., Boer, J. M., Brenner, H., Casiglia, E., Chiodini, P., Cooper, J. A., Coresh, J., Cushman, M., Dankner, R., Davidson, K. W., de Jongh, R. T., Donfrancesco, C., Engstrom, G., Freisling, H., de la Camara, A. G., Gudnason, V., Hankey, G. J., Hansson, P., Heath, A. K., Hoorn, E. J., Imano, H., Jassal, S. K., Kaaks, R., Katzke, V., Kauhanen, J., Kiechl, S., Koenig, W., Kronmal, R. A., Kyro, C., Lawlor, D. A., Ljungberg, B., MacDonald, C., Masala, G., Meisinger, C., Melander, O., Moreno Iribas, C., Ninomiya, T., Nitsch, D., Nordestgaard, B. G., Onland-Moret, C., Palmieri, L., Petrova, D., Garcia, J. R., Rosengren, A., Sacerdote, C., Sakurai, M., Santiuste, C., Schulze, M. B., Sieri, S., Sundstrom, J., Tikhonoff, V., Tjonneland, A., Tong, T., Tumino, R., Tzoulaki, I., van der Schouw, Y. T., Monique Verschuren, W. M., Volzke, H., Wallace, R. B., Goya Wannamethee, S., Weiderpass, E., Willeit, P., Woodward, M., Yamagishi, K., Zamora-Ros, R., Akwo, E. A., Pyarajan, S., Gagnon, D. R., Tsao, P. S., Muralidhar, S., Edwards, T. L., Damrauer, S. M., Joseph, J., Pennells, L., Wilson, P. W., Harrison, S., Gaziano, T. A., Inouye, M., Million Veteran Program, Baigent, C., Casas, J. P., Langenberg, C., Wareham, N., Riboli, E., Michael Gaziano, J., Danesh, J., Hung, A. M., Butterworth, A. S., Wood, A. M., Di Angelantonio, E., Emerging Risk Factors Collaboration/EPIC-CVD/Million Veteran Program, Koettgen, A., Shaw, J., Atkins, R., Zimmet, P., Whincup, P., Willeit, J., Leitner, C., Schnohr, P., Afzal, S., Pablos, D. L., Arriscado, C. M., Ferreiro, C. R., Stocker, H., Schottker, B., Holleczek, B., Chetrit, A., Welin, L., Svardsudd, K., Welin, L., Svardsudd, K., Lissner, L., Hange, D., Mehlig, K., Nagel, D., Norman, P. E., Almeida, O., Flicker, L., Hata, J., Honda, T., Furuta, Y., Iso, H., Kitamura, A., Muraki, I., Salonen, J. T., Tuomainen, T., van Zutphen, E. M., van Schoor, N. M., Lo Noce, C., Lappas, G., Nilsson, P. M., Hedblad, B., Shaffer, J., Schwartz, J., Shimbo, D., Sato, S., Iso, H., Hayama-Terada, M., Aspelund, T., Thorsson, B., Sigurdsson, G., Chaker, L., Ikram, K. M., Kavousi, M., Tunstall-Pedoe, H., Can, G., Yuksel, H., Ozkan, U., Nakagawa, H., Morikawa, Y., Ishizaki, M., Feskens, E., Geleijnse, J. M., Kromhout, D. 2022

    Abstract

    BACKGROUND: End-stage renal disease is associated with a high risk of cardiovascular events. It is unknown, however, whether mild-to-moderate kidney dysfunction is causally related to coronary heart disease (CHD) and stroke.METHODS: Observational analyses were conducted using individual-level data from 4 population data sources (Emerging Risk Factors Collaboration, EPIC-CVD [European Prospective Investigation into Cancer and Nutrition-Cardiovascular Disease Study], Million Veteran Program, and UK Biobank), comprising 648135 participants with no history of cardiovascular disease or diabetes at baseline, yielding 42858 and 15693 incident CHD and stroke events, respectively, during 6.8 million person-years of follow-up. Using a genetic risk score of 218 variants for estimated glomerular filtration rate (eGFR), we conducted Mendelian randomization analyses involving 413718 participants (25917 CHD and 8622 strokes) in EPIC-CVD, Million Veteran Program, and UK Biobank.RESULTS: There were U-shaped observational associations of creatinine-based eGFR with CHD and stroke, with higher risk in participants with eGFR values <60 or >105 mL·min-1·1.73 m-2, compared with those with eGFR between 60 and 105 mL·min-1·1.73 m-2. Mendelian randomization analyses for CHD showed an association among participants with eGFR <60 mL·min-1·1.73 m-2, with a 14% (95% CI, 3%-27%) higher CHD risk per 5 mL·min-1·1.73 m-2 lower genetically predicted eGFR, but not for those with eGFR >105 mL·min-1·1.73 m-2. Results were not materially different after adjustment for factors associated with the eGFR genetic risk score, such as lipoprotein(a), triglycerides, hemoglobin A1c, and blood pressure. Mendelian randomization results for stroke were nonsignificant but broadly similar to those for CHD.CONCLUSIONS: In people without manifest cardiovascular disease or diabetes, mild-to-moderate kidney dysfunction is causally related to risk of CHD, highlighting the potential value of preventive approaches that preserve and modulate kidney function.

    View details for DOI 10.1161/CIRCULATIONAHA.122.060700

    View details for PubMedID 36314129

  • A GENOTYPE-FIRST APPROACH TO DEFINING THE HEPATOBILIARY PHENOTYPES IN CARRIERS OF THE AFRICAN-ANCESTRY SPECIFIC ABCB4 MISSENSE VARIANT P.ALA934THR Mezina, A., Vujkovic, M., Park, J., Lynch, J. A., Voight, B. F., Tsao, P. S., Kaplan, D. E., Chang, K., Wangensteen, K., Rader, D. J. WILEY. 2022: S1283
  • GERMLINE SUSCEPTIBILITY TO HEPATOCELLULAR CARCINOMA AMONG PATIENTS WITH CIRRHOSIS: A GENOME-WIDE ASSOCIATION STUDY Kaplan, D. E., Vujkovic, M., Dochtermann, D., Chang, B., Hoteit, M. A., Wangensteen, K., Keating, B., Shaked, A., Olthoff, K. M., Asrani, S. K., Testa, G., Trotter, J. F., Klintmalm, G. B., Devineni, P., Schwantes-An, T., Sendamarai, A., Karnam, P., Sileo, E., Anglin, T., Norden-Krichmar, T., Lewis, A., Bastarache, L., Schneider, C., Tsao, P., Morgan, T. R., Pyarajan, S., Lynch, J. A., Voight, B. F., Chang, K. WILEY. 2022: S182-S183
  • A multi-layer functional genomic analysis to understand noncoding genetic variation in lipids. American journal of human genetics Ramdas, S., Judd, J., Graham, S. E., Kanoni, S., Wang, Y., Surakka, I., Wenz, B., Clarke, S. L., Chesi, A., Wells, A., Bhatti, K. F., Vedantam, S., Winkler, T. W., Locke, A. E., Marouli, E., Zajac, G. J., Wu, K. H., Ntalla, I., Hui, Q., Klarin, D., Hilliard, A. T., Wang, Z., Xue, C., Thorleifsson, G., Helgadottir, A., Gudbjartsson, D. F., Holm, H., Olafsson, I., Hwang, M. Y., Han, S., Akiyama, M., Sakaue, S., Terao, C., Kanai, M., Zhou, W., Brumpton, B. M., Rasheed, H., Havulinna, A. S., Veturi, Y., Pacheco, J. A., Rosenthal, E. A., Lingren, T., Feng, Q., Kullo, I. J., Narita, A., Takayama, J., Martin, H. C., Hunt, K. A., Trivedi, B., Haessler, J., Giulianini, F., Bradford, Y., Miller, J. E., Campbell, A., Lin, K., Millwood, I. Y., Rasheed, A., Hindy, G., Faul, J. D., Zhao, W., Weir, D. R., Turman, C., Huang, H., Graff, M., Choudhury, A., Sengupta, D., Mahajan, A., Brown, M. R., Zhang, W., Yu, K., Schmidt, E. M., Pandit, A., Gustafsson, S., Yin, X., Luan, J., Zhao, J. H., Matsuda, F., Jang, H. M., Yoon, K., Medina-Gomez, C., Pitsillides, A., Hottenga, J. J., Wood, A. R., Ji, Y., Gao, Z., Haworth, S., Mitchell, R. E., Chai, J. F., Aadahl, M., Bjerregaard, A. A., Yao, J., Manichaikul, A., Lee, W. J., Hsiung, C. A., Warren, H. R., Ramirez, J., Bork-Jensen, J., Kårhus, L. L., Goel, A., Sabater-Lleal, M., Noordam, R., Mauro, P., Matteo, F., McDaid, A. F., Marques-Vidal, P., Wielscher, M., Trompet, S., Sattar, N., Møllehave, L. T., Munz, M., Zeng, L., Huang, J., Yang, B., Poveda, A., Kurbasic, A., Schönherr, S., Forer, L., Scholz, M., Galesloot, T. E., Bradfield, J. P., Ruotsalainen, S. E., Daw, E. W., Zmuda, J. M., Mitchell, J. S., Fuchsberger, C., Christensen, H., Brody, J. A., Le, P., Feitosa, M. F., Wojczynski, M. K., Hemerich, D., Preuss, M., Mangino, M., Christofidou, P., Verweij, N., Benjamins, J. W., Engmann, J., Noah, T. L., Verma, A., Slieker, R. C., Lo, K. S., Zilhao, N. R., Kleber, M. E., Delgado, G. E., Huo, S., Ikeda, D. D., Iha, H., Yang, J., Liu, J., Demirkan, A., Leonard, H. L., Marten, J., Emmel, C., Schmidt, B., Smyth, L. J., Cañadas-Garre, M., Wang, C., Nakatochi, M., Wong, A., Hutri-Kähönen, N., Sim, X., Xia, R., Huerta-Chagoya, A., Fernandez-Lopez, J. C., Lyssenko, V., Nongmaithem, S. S., Sankareswaran, A., Irvin, M. R., Oldmeadow, C., Kim, H. N., Ryu, S., Timmers, P. R., Arbeeva, L., Dorajoo, R., Lange, L. A., Prasad, G., Lorés-Motta, L., Pauper, M., Long, J., Li, X., Theusch, E., Takeuchi, F., Spracklen, C. N., Loukola, A., Bollepalli, S., Warner, S. C., Wang, Y. X., Wei, W. B., Nutile, T., Ruggiero, D., Sung, Y. J., Chen, S., Liu, F., Yang, J., Kentistou, K. A., Banas, B., Morgan, A., Meidtner, K., Bielak, L. F., Smith, J. A., Hebbar, P., Farmaki, A. E., Hofer, E., Lin, M., Concas, M. P., Vaccargiu, S., van der Most, P. J., Pitkänen, N., Cade, B. E., van der Laan, S. W., Chitrala, K. N., Weiss, S., Bentley, A. R., Doumatey, A. P., Adeyemo, A. A., Lee, J. Y., Petersen, E. R., Nielsen, A. A., Choi, H. S., Nethander, M., Freitag-Wolf, S., Southam, L., Rayner, N. W., Wang, C. A., Lin, S. Y., Wang, J. S., Couture, C., Lyytikäinen, L. P., Nikus, K., Cuellar-Partida, G., Vestergaard, H., Hidalgo, B., Giannakopoulou, O., Cai, Q., Obura, M. O., van Setten, J., He, K. Y., Tang, H., Terzikhan, N., Shin, J. H., Jackson, R. D., Reiner, A. P., Martin, L. W., Chen, Z., Li, L., Kawaguchi, T., Thiery, J., Bis, J. C., Launer, L. J., Li, H., Nalls, M. A., Raitakari, O. T., Ichihara, S., Wild, S. H., Nelson, C. P., Campbell, H., Jäger, S., Nabika, T., Al-Mulla, F., Niinikoski, H., Braund, P. S., Kolcic, I., Kovacs, P., Giardoglou, T., Katsuya, T., de Kleijn, D., de Borst, G. J., Kim, E. K., Adams, H. H., Ikram, M. A., Zhu, X., Asselbergs, F. W., Kraaijeveld, A. O., Beulens, J. W., Shu, X. O., Rallidis, L. S., Pedersen, O., Hansen, T., Mitchell, P., Hewitt, A. W., Kähönen, M., Pérusse, L., Bouchard, C., Tönjes, A., Ida Chen, Y. D., Pennell, C. E., Mori, T. A., Lieb, W., Franke, A., Ohlsson, C., Mellström, D., Cho, Y. S., Lee, H., Yuan, J. M., Koh, W. P., Rhee, S. Y., Woo, J. T., Heid, I. M., Stark, K. J., Zimmermann, M. E., Völzke, H., Homuth, G., Evans, M. K., Zonderman, A. B., Polasek, O., Pasterkamp, G., Hoefer, I. E., Redline, S., Pahkala, K., Oldehinkel, A. J., Snieder, H., Biino, G., Schmidt, R., Schmidt, H., Bandinelli, S., Dedoussis, G., Thanaraj, T. A., Peyser, P. A., Kato, N., Schulze, M. B., Girotto, G., Böger, C. A., Jung, B., Joshi, P. K., Bennett, D. A., De Jager, P. L., Lu, X., Mamakou, V., Brown, M., Caulfield, M. J., Munroe, P. B., Guo, X., Ciullo, M., Jonas, J. B., Samani, N. J., Kaprio, J., Pajukanta, P., Tusié-Luna, T., Aguilar-Salinas, C. A., Adair, L. S., Bechayda, S. A., de Silva, H. J., Wickremasinghe, A. R., Krauss, R. M., Wu, J. Y., Zheng, W., den Hollander, A. I., Bharadwaj, D., Correa, A., Wilson, J. G., Lind, L., Heng, C. K., Nelson, A. E., Golightly, Y. M., Wilson, J. F., Penninx, B., Kim, H. L., Attia, J., Scott, R. J., Rao, D. C., Arnett, D. K., Walker, M., Scott, L. J., Koistinen, H. A., Chandak, G. R., Mercader, J. M., Villalpando, C. G., Orozco, L., Fornage, M., Tai, E. S., van Dam, R. M., Lehtimäki, T., Chaturvedi, N., Yokota, M., Liu, J., Reilly, D. F., McKnight, A. J., Kee, F., Jöckel, K. H., McCarthy, M. I., Palmer, C. N., Vitart, V., Hayward, C., Simonsick, E., van Duijn, C. M., Jin, Z. B., Lu, F., Hishigaki, H., Lin, X., März, W., Gudnason, V., Tardif, J. C., Lettre, G., T Hart, L. M., Elders, P. J., Rader, D. J., Damrauer, S. M., Kumari, M., Kivimaki, M., van der Harst, P., Spector, T. D., Loos, R. J., Province, M. A., Parra, E. J., Cruz, M., Psaty, B. M., Brandslund, I., Pramstaller, P. P., Rotimi, C. N., Christensen, K., Ripatti, S., Widén, E., Hakonarson, H., Grant, S. F., Kiemeney, L., de Graaf, J., Loeffler, M., Kronenberg, F., Gu, D., Erdmann, J., Schunkert, H., Franks, P. W., Linneberg, A., Jukema, J. W., Khera, A. V., Männikkö, M., Jarvelin, M. R., Kutalik, Z., Francesco, C., Mook-Kanamori, D. O., Willems van Dijk, K., Watkins, H., Strachan, D. P., Grarup, N., Sever, P., Poulter, N., Huey-Herng Sheu, W., Rotter, J. I., Dantoft, T. M., Karpe, F., Neville, M. J., Timpson, N. J., Cheng, C. Y., Wong, T. Y., Khor, C. C., Li, H., Sabanayagam, C., Peters, A., Gieger, C., Hattersley, A. T., Pedersen, N. L., Magnusson, P. K., Boomsma, D. I., de Geus, E. J., Cupples, L. A., van Meurs, J. B., Ikram, A., Ghanbari, M., Gordon-Larsen, P., Huang, W., Kim, Y. J., Tabara, Y., Wareham, N. J., Langenberg, C., Zeggini, E., Tuomilehto, J., Kuusisto, J., Laakso, M., Ingelsson, E., Abecasis, G., Chambers, J. C., Kooner, J. S., de Vries, P. S., Morrison, A. C., Hazelhurst, S., Ramsay, M., North, K. E., Daviglus, M., Kraft, P., Martin, N. G., Whitfield, J. B., Abbas, S., Saleheen, D., Walters, R. G., Holmes, M. V., Black, C., Smith, B. H., Baras, A., Justice, A. E., Buring, J. E., Ridker, P. M., Chasman, D. I., Kooperberg, C., Tamiya, G., Yamamoto, M., van Heel, D. A., Trembath, R. C., Wei, W. Q., Jarvik, G. P., Namjou, B., Hayes, M. G., Ritchie, M. D., Jousilahti, P., Salomaa, V., Hveem, K., Åsvold, B. O., Kubo, M., Kamatani, Y., Okada, Y., Murakami, Y., Kim, B. J., Thorsteinsdottir, U., Stefansson, K., Zhang, J., Chen, Y. E., Ho, Y. L., Lynch, J. A., Tsao, P. S., Chang, K. M., Cho, K., O'Donnell, C. J., Gaziano, J. M., Wilson, P., Mohlke, K. L., Frayling, T. M., Hirschhorn, J. N., Kathiresan, S., Boehnke, M., Natarajan, P., Sun, Y. V., Morris, A. P., Deloukas, P., Peloso, G., Assimes, T. L., Willer, C. J., Zhu, X., Brown, C. D. 2022; 109 (8): 1366-1387

    Abstract

    A major challenge of genome-wide association studies (GWASs) is to translate phenotypic associations into biological insights. Here, we integrate a large GWAS on blood lipids involving 1.6 million individuals from five ancestries with a wide array of functional genomic datasets to discover regulatory mechanisms underlying lipid associations. We first prioritize lipid-associated genes with expression quantitative trait locus (eQTL) colocalizations and then add chromatin interaction data to narrow the search for functional genes. Polygenic enrichment analysis across 697 annotations from a host of tissues and cell types confirms the central role of the liver in lipid levels and highlights the selective enrichment of adipose-specific chromatin marks in high-density lipoprotein cholesterol and triglycerides. Overlapping transcription factor (TF) binding sites with lipid-associated loci identifies TFs relevant in lipid biology. In addition, we present an integrative framework to prioritize causal variants at GWAS loci, producing a comprehensive list of candidate causal genes and variants with multiple layers of functional evidence. We highlight two of the prioritized genes, CREBRF and RRBP1, which show convergent evidence across functional datasets supporting their roles in lipid biology.

    View details for DOI 10.1016/j.ajhg.2022.06.012

    View details for PubMedID 35931049

  • Large-scale genome-wide association study of coronary artery disease in genetically diverse populations. Nature medicine Tcheandjieu, C., Zhu, X., Hilliard, A. T., Clarke, S. L., Napolioni, V., Ma, S., Lee, K. M., Fang, H., Chen, F., Lu, Y., Tsao, N. L., Raghavan, S., Koyama, S., Gorman, B. R., Vujkovic, M., Klarin, D., Levin, M. G., Sinnott-Armstrong, N., Wojcik, G. L., Plomondon, M. E., Maddox, T. M., Waldo, S. W., Bick, A. G., Pyarajan, S., Huang, J., Song, R., Ho, Y. L., Buyske, S., Kooperberg, C., Haessler, J., Loos, R. J., Do, R., Verbanck, M., Chaudhary, K., North, K. E., Avery, C. L., Graff, M., Haiman, C. A., Le Marchand, L., Wilkens, L. R., Bis, J. C., Leonard, H., Shen, B., Lange, L. A., Giri, A., Dikilitas, O., Kullo, I. J., Stanaway, I. B., Jarvik, G. P., Gordon, A. S., Hebbring, S., Namjou, B., Kaufman, K. M., Ito, K., Ishigaki, K., Kamatani, Y., Verma, S. S., Ritchie, M. D., Kember, R. L., Baras, A., Lotta, L. A., Kathiresan, S., Hauser, E. R., Miller, D. R., Lee, J. S., Saleheen, D., Reaven, P. D., Cho, K., Gaziano, J. M., Natarajan, P., Huffman, J. E., Voight, B. F., Rader, D. J., Chang, K. M., Lynch, J. A., Damrauer, S. M., Wilson, P. W., Tang, H., Sun, Y. V., Tsao, P. S., O'Donnell, C. J., Assimes, T. L. 2022

    Abstract

    We report a genome-wide association study (GWAS) of coronary artery disease (CAD) incorporating nearly a quarter of a million cases, in which existing studies are integrated with data from cohorts of white, Black and Hispanic individuals from the Million Veteran Program. We document near equivalent heritability of CAD across multiple ancestral groups, identify 95 novel loci, including nine on the X chromosome, detect eight loci of genome-wide significance in Black and Hispanic individuals, and demonstrate that two common haplotypes at the 9p21 locus are responsible for risk stratification in all populations except those of African origin, in which these haplotypes are virtually absent. Moreover, in the largest GWAS for angiographically derived coronary atherosclerosis performed to date, we find 15 loci of genome-wide significance that robustly overlap with established loci for clinical CAD. Phenome-wide association analyses of novel loci and polygenic risk scores (PRSs) augment signals related to insulin resistance, extend pleiotropic associations of these loci to include smoking and family history, and precisely document the markedly reduced transferability of existing PRSs to Black individuals. Downstream integrative analyses reinforce the critical roles of vascular endothelial, fibroblast, and smooth muscle cells in CAD susceptibility, but also point to a shared biology between atherosclerosis and oncogenesis. This study highlights the value of diverse populations in further characterizing the genetic architecture of CAD.

    View details for DOI 10.1038/s41591-022-01891-3

    View details for PubMedID 35915156

  • Race and Ethnicity Stratification for Polygenic Risk Score Analyses May Mask Disparities in Hispanics CIRCULATION Clarke, S. L., Huang, R. L., Hilliard, A. T., Tcheandjieu, C., Lynch, J., Damrauer, S. M., Chang, K., Tsao, P. S., Assimes, T. L. 2022; 146 (3): 265-267
  • Race and Ethnicity Stratification for Polygenic Risk Score Analyses May Mask Disparities in Hispanics. Circulation Clarke, S. L., Huang, R. D., Hilliard, A. T., Tcheandjieu, C., Lynch, J., Damrauer, S. M., Chang, K. M., Tsao, P. S., Assimes, T. L. 2022; 146 (3): 265-267

    View details for DOI 10.1161/CIRCULATIONAHA.122.059162

    View details for PubMedID 35861770

  • Role of MicroRNAs in acceleration of vascular endothelial senescence. Biochemistry and biophysics reports Toyama, K., Spin, J. M., Deng, A. C., Abe, Y., Tsao, P. S., Mogi, M. 2022; 30: 101281

    Abstract

    Backgrounds: Many factors are involved in cellular aging, and senescence induction requires complex regulation of various signaling networks and processes. Specifically, in the area of aging-related vascular cognitive impairment, laboratory-based findings have not yet yielded agents of practical use for clinical settings. One possible reason is that the physiologic elements of aging have been insufficiently considered. We sought to establish techniques to better model cellular aging using modulation of microRNAs, aiming to identify key microRNAs capable of fine-tuning aging-associated genes, and thereby regulating the senescence of vascular endothelial cells.Methods: We utilized expression microRNA arrays to evaluate control and senescent vascular endothelial cells in order to identify testable candidates. Bioinformatic analysis was used to select key microRNAs. These candidates were then modulated in vitro using microRNA mimics and inhibitors in endothelial cells, and senescence-associated gene expression patterns were evaluated by qPCR.Results: Seventeen microRNAs were found to be significantly increased more than 2-fold in senescent cells. Of those, bioinformatic analysis concluded that miR-181a-5p, miR-30a-5p, miR-30a-3p, miR-100-5p, miR-21-5p, and miR-382-5p were likely associated with regulation of cellular senescence. We evaluated the potential targets of these six microRNAs by comparing them with cell-cycling and apoptosis-related genes from published mRNA transcriptional array data from aged tissues, and found that miR-181a-5p, miR-30a-5p and miR-30a-3p were enriched in overlapping targets compared with the other candidates. Modulation of these microRNAs in vascular endothelial cells revealed that over-expression of miR-30a-5p, and inhibition of both miR-30a-3p and miR-181a-5p, induced senescence.Conclusion: miR-181a-5p, miR-30a-5p and miR-30a-3p likely contribute to aging-associated vascular endothelial cell senescence.

    View details for DOI 10.1016/j.bbrep.2022.101281

    View details for PubMedID 35651952

  • Linear slope of serial FIB-4 measurements predicts liver-related complications and correlates with cirrhosis-associated genetic variants among patients with ALT-based NAFLD phenotype Teerlink, C., Kaplan, D. E., Vujkovic, M., Voight, B., Chang, K., Lynch, J., Duvall, S., Anglin, T., Morgan, T., Tae-Hwi, L., Norden-Krichmar, T., Dochterman, D., Devineni, P., Tsao, P., Schneider, C. ELSEVIER. 2022: S30-S31
  • Genetic interactions drive heterogeneity in causal variant effect sizes for gene expression and complex traits. American journal of human genetics Patel, R. A., Musharoff, S. A., Spence, J. P., Pimentel, H., Tcheandjieu, C., Mostafavi, H., Sinnott-Armstrong, N., Clarke, S. L., Smith, C. J., V.A. Million Veteran Program,,, Durda, P. P., Taylor, K. D., Tracy, R., Liu, Y., Johnson, W. C., Aguet, F., Ardlie, K. G., Gabriel, S., Smith, J., Nickerson, D. A., Rich, S. S., Rotter, J. I., Tsao, P. S., Assimes, T. L., Pritchard, J. K. 2022

    Abstract

    Despite the growing number of genome-wide association studies (GWASs), it remains unclear to what extent gene-by-gene and gene-by-environment interactions influence complex traits in humans. The magnitude of genetic interactions in complex traits has been difficult to quantify because GWASs are generally underpowered to detect individual interactions of small effect. Here, we develop a method to test for genetic interactions that aggregates information across all trait-associated loci. Specifically, we test whether SNPs in regions of European ancestry shared between European American and admixed African American individuals have the same causal effect sizes. We hypothesize that in African Americans, the presence of genetic interactions will drive the causal effect sizes of SNPs in regions of European ancestry to be more similar to those of SNPs in regions of African ancestry. We apply our method to two traits: gene expression in 296 African Americans and 482 European Americans in the Multi-Ethnic Study of Atherosclerosis (MESA) and low-density lipoprotein cholesterol (LDL-C) in 74K African Americans and 296K European Americans in the Million Veteran Program (MVP). We find significant evidence for genetic interactions in our analysis of gene expression; for LDL-C, we observe a similar point estimate, although this is not significant, most likely due to lower statistical power. These results suggest that gene-by-gene or gene-by-environment interactions modify the effect sizes of causal variants in human complex traits.

    View details for DOI 10.1016/j.ajhg.2022.05.014

    View details for PubMedID 35716666

  • Multiomic analysis reveals cell-type-specific molecular determinants of COVID-19 severity. Cell systems Zhang, S., Cooper-Knock, J., Weimer, A. K., Shi, M., Kozhaya, L., Unutmaz, D., Harvey, C., Julian, T. H., Furini, S., Frullanti, E., Fava, F., Renieri, A., Gao, P., Shen, X., Timpanaro, I. S., Kenna, K. P., Baillie, J. K., Davis, M. M., Tsao, P. S., Snyder, M. P. 2022

    Abstract

    The determinants of severe COVID-19 in healthy adults are poorly understood, which limits the opportunity for early intervention. We present a multiomic analysis using machine learning to characterize the genomic basis of COVID-19 severity. We use single-cell multiome profiling of human lungs to link genetic signals to cell-type-specific functions. We discover >1,000 risk genes across 19 cell types, which account for 77% of the SNP-based heritability for severe disease. Genetic risk is particularly focused within natural killer (NK) cells and T cells, placing the dysfunction of these cells upstream of severe disease. Mendelian randomization and single-cell profiling of human NK cells support the role of NK cells and further localize genetic risk to CD56bright NK cells, which are key cytokine producers during the innate immune response. Rare variant analysis confirms the enrichment of severe-disease-associated genetic variation within NK-cell risk genes. Our study provides insights into the pathogenesis of severe COVID-19 with potential therapeutic targets.

    View details for DOI 10.1016/j.cels.2022.05.007

    View details for PubMedID 35690068

  • A multiancestry genome-wide association study of unexplained chronic ALT elevation as a proxy for nonalcoholic fatty liver disease with histological and radiological validation. Nature genetics Vujkovic, M., Ramdas, S., Lorenz, K. M., Guo, X., Darlay, R., Cordell, H. J., He, J., Gindin, Y., Chung, C., Myers, R. P., Schneider, C. V., Park, J., Lee, K. M., Serper, M., Carr, R. M., Kaplan, D. E., Haas, M. E., MacLean, M. T., Witschey, W. R., Zhu, X., Tcheandjieu, C., Kember, R. L., Kranzler, H. R., Verma, A., Giri, A., Klarin, D. M., Sun, Y. V., Huang, J., Huffman, J. E., Townsend Creasy, K., Hand, N. J., Liu, C., Long, M. T., Yao, J., Budoff, M., Tan, J., Li, X., Lin, H. J., Chen, Y. I., Taylor, K. D., Chang, R., Krauss, R. M., Vilarinho, S., Brancale, J., Nielsen, J. B., Locke, A. E., Jones, M. B., Verweij, N., Baras, A., Reddy, K. R., Neuschwander-Tetri, B. A., Schwimmer, J. B., Sanyal, A. J., Chalasani, N., Ryan, K. A., Mitchell, B. D., Gill, D., Wells, A. D., Manduchi, E., Saiman, Y., Mahmud, N., Miller, D. R., Reaven, P. D., Phillips, L. S., Muralidhar, S., DuVall, S. L., Lee, J. S., Assimes, T. L., Pyarajan, S., Cho, K., Edwards, T. L., Damrauer, S. M., Wilson, P. W., Gaziano, J. M., O'Donnell, C. J., Khera, A. V., Grant, S. F., Brown, C. D., Tsao, P. S., Saleheen, D., Lotta, L. A., Bastarache, L., Anstee, Q. M., Daly, A. K., Meigs, J. B., Rotter, J. I., Lynch, J. A., Regeneron Genetics Center, Geisinger-Regeneron DiscovEHR Collaboration, EPoS Consortium, VA Million Veteran Program, Rader, D. J., Voight, B. F., Chang, K. 2022

    Abstract

    Nonalcoholic fatty liver disease (NAFLD) is a growing cause of chronic liver disease. Using a proxy NAFLD definition of chronic elevation of alanine aminotransferase (cALT) levels without other liver diseases, we performed a multiancestry genome-wide association study (GWAS) in the Million Veteran Program (MVP) including 90,408 cALT cases and 128,187 controls. Seventy-seven loci exceeded genome-wide significance, including 25 without prior NAFLD or alanine aminotransferase associations, with one additional locus identified in European American-only and two in African American-only analyses (P<5 * 10-8). External replication in histology-defined NAFLD cohorts (7,397 cases and 56,785 controls) or radiologic imaging cohorts (n=44,289) replicated 17 single-nucleotide polymorphisms (SNPs) (P<6.5 * 10-4), of which 9 were new (TRIB1, PPARG, MTTP, SERPINA1, FTO, IL1RN, COBLL1, APOH and IFI30). Pleiotropy analysis showed that 61 of 77 multiancestry and all 17 replicated SNPs were jointly associated with metabolic and/or inflammatory traits, revealing a complex model of genetic architecture. Our approach integrating cALT, histology and imaging reveals new insights into genetic liability to NAFLD.

    View details for DOI 10.1038/s41588-022-01078-z

    View details for PubMedID 35654975

  • A multi-population phenome-wide association study of genetically-predicted height in the Million Veteran Program. PLoS genetics Raghavan, S., Huang, J., Tcheandjieu, C., Huffman, J. E., Litkowski, E., Liu, C., Ho, Y. A., Hunter-Zinck, H., Zhao, H., Marouli, E., North, K. E., VA Million Veteran Program, Lange, E., Lange, L. A., Voight, B. F., Gaziano, J. M., Pyarajan, S., Hauser, E. R., Tsao, P. S., Wilson, P. W., Chang, K., Cho, K., O'Donnell, C. J., Sun, Y. V., Assimes, T. L. 2022; 18 (6): e1010193

    Abstract

    BACKGROUND: Height has been associated with many clinical traits but whether such associations are causal versus secondary to confounding remains unclear in many cases. To systematically examine this question, we performed a Mendelian Randomization-Phenome-wide association study (MR-PheWAS) using clinical and genetic data from a national healthcare system biobank.METHODS AND FINDINGS: Analyses were performed using data from the US Veterans Affairs (VA) Million Veteran Program in non-Hispanic White (EA, n = 222,300) and non-Hispanic Black (AA, n = 58,151) adults in the US. We estimated height genetic risk based on 3290 height-associated variants from a recent European-ancestry genome-wide meta-analysis. We compared associations of measured and genetically-predicted height with phenome-wide traits derived from the VA electronic health record, adjusting for age, sex, and genetic principal components. We found 345 clinical traits associated with measured height in EA and an additional 17 in AA. Of these, 127 were associated with genetically-predicted height at phenome-wide significance in EA and 2 in AA. These associations were largely independent from body mass index. We confirmed several previously described MR associations between height and cardiovascular disease traits such as hypertension, hyperlipidemia, coronary heart disease (CHD), and atrial fibrillation, and further uncovered MR associations with venous circulatory disorders and peripheral neuropathy in the presence and absence of diabetes. As a number of traits associated with genetically-predicted height frequently co-occur with CHD, we evaluated effect modification by CHD status of genetically-predicted height associations with risk factors for and complications of CHD. We found modification of effects of MR associations by CHD status for atrial fibrillation/flutter but not for hypertension, hyperlipidemia, or venous circulatory disorders.CONCLUSIONS: We conclude that height may be an unrecognized but biologically plausible risk factor for several common conditions in adults. However, more studies are needed to reliably exclude horizontal pleiotropy as a driving force behind at least some of the MR associations observed in this study.

    View details for DOI 10.1371/journal.pgen.1010193

    View details for PubMedID 35653334

  • High heritability of ascending aortic diameter and trans-ancestry prediction of thoracic aortic disease. Nature genetics Tcheandjieu, C., Xiao, K., Tejeda, H., Lynch, J. A., Ruotsalainen, S., Bellomo, T., Palnati, M., Judy, R., Klarin, D., Kember, R. L., Verma, S., Palotie, A., Daly, M., Ritchie, M., Rader, D. J., Rivas, M. A., Assimes, T., Tsao, P., Damrauer, S., Priest, J. R. 2022

    Abstract

    Enlargement of the aorta is an important risk factor for aortic aneurysm and dissection, a leading cause of morbidity in the developed world. Here we performed automated extraction of ascending aortic diameter from cardiac magnetic resonance images of 36,021 individuals from the UK Biobank, followed by genome-wide association. We identified lead variants across 41 loci, including genes related to cardiovascular development (HAND2, TBX20) and Mendelian forms of thoracic aortic disease (ELN, FBN1). A polygenic score significantly predicted prevalent risk of thoracic aortic aneurysm and the need for surgical intervention for patients with thoracic aneurysm across multiple ancestries within the UK Biobank, FinnGen, the Penn Medicine Biobank and the Million Veterans Program (MVP). Additionally, we highlight the primary causal role of blood pressure in reducing aortic dilation using Mendelian randomization. Overall, our findings provide a roadmap for using genetic determinants of human anatomy to understand cardiovascular development while improving prediction of diseases of the thoracic aorta.

    View details for DOI 10.1038/s41588-022-01070-7

    View details for PubMedID 35637384

  • Genome-wide association study and replication of liver enzyme loci Pazoki, R., Vujkovic, M., Elliott, J., Evangelou, E., Gill, D., Ghanbari, M., Van der Most, P. J., Pinto, R., Wielscher, M., Farlik, M., Zuber, V., de Knegt, R. J., Snieder, H., Uitterlinden, A. G., Lynch, J. A., Jiang, X., Said, S., Kaplan, D. E., Lee, K., Serper, M., Carr, R. M., Tsao, P. S., Atkinson, S. R., Dehghan, A., Tzoulaki, I., Ikram, A., Herzig, K., Jarvelin, M., Alizadeh, B. Z., O'Don-Nell, C. J., Saleheen, D., Voight, B. F., Chang, K., Thursz, M. R., Elliott, P., Lifelines Cohort Study, V A Million Veteran Program SPRINGERNATURE. 2022: 47-48
  • A Phenome-Wide Association Study of genes associated with COVID-19 severity reveals shared genetics with complex diseases in the Million Veteran Program. PLoS genetics Verma, A., Tsao, N. L., Thomann, L. O., Ho, Y., Iyengar, S. K., Luoh, S., Carr, R., Crawford, D. C., Efird, J. T., Huffman, J. E., Hung, A., Ivey, K. L., Levin, M. G., Lynch, J., Natarajan, P., Pyarajan, S., Bick, A. G., Costa, L., Genovese, G., Hauger, R., Madduri, R., Pathak, G. A., Polimanti, R., Voight, B., Vujkovic, M., Zekavat, S. M., Zhao, H., Ritchie, M. D., VA Million Veteran Program COVID-19 Science Initiative, Chang, K., Cho, K., Casas, J. P., Tsao, P. S., Gaziano, J. M., O'Donnell, C., Damrauer, S. M., Liao, K. P. 2022; 18 (4): e1010113

    Abstract

    The study aims to determine the shared genetic architecture between COVID-19 severity with existing medical conditions using electronic health record (EHR) data. We conducted a Phenome-Wide Association Study (PheWAS) of genetic variants associated with critical illness (n = 35) or hospitalization (n = 42) due to severe COVID-19 using genome-wide association summary data from the Host Genetics Initiative. PheWAS analysis was performed using genotype-phenotype data from the Veterans Affairs Million Veteran Program (MVP). Phenotypes were defined by International Classification of Diseases (ICD) codes mapped to clinically relevant groups using published PheWAS methods. Among 658,582 Veterans, variants associated with severe COVID-19 were tested for association across 1,559 phenotypes. Variants at the ABO locus (rs495828, rs505922) associated with the largest number of phenotypes (nrs495828 = 53 and nrs505922 = 59); strongest association with venous embolism, odds ratio (ORrs495828 1.33 (p = 1.32 x 10-199), and thrombosis ORrs505922 1.33, p = 2.2 x10-265. Among 67 respiratory conditions tested, 11 had significant associations including MUC5B locus (rs35705950) with increased risk of idiopathic fibrosing alveolitis OR 2.83, p = 4.12 * 10-191; CRHR1 (rs61667602) associated with reduced risk of pulmonary fibrosis, OR 0.84, p = 2.26* 10-12. The TYK2 locus (rs11085727) associated with reduced risk for autoimmune conditions, e.g., psoriasis OR 0.88, p = 6.48 x10-23, lupus OR 0.84, p = 3.97 x 10-06. PheWAS stratified by ancestry demonstrated differences in genotype-phenotype associations. LMNA (rs581342) associated with neutropenia OR 1.29 p = 4.1 x 10-13 among Veterans of African and Hispanic ancestry but not European. Overall, we observed a shared genetic architecture between COVID-19 severity and conditions related to underlying risk factors for severe and poor COVID-19 outcomes. Differing associations between genotype-phenotype across ancestries may inform heterogenous outcomes observed with COVID-19. Divergent associations between risk for severe COVID-19 with autoimmune inflammatory conditions both respiratory and non-respiratory highlights the shared pathways and fine balance of immune host response and autoimmunity and caution required when considering treatment targets.

    View details for DOI 10.1371/journal.pgen.1010113

    View details for PubMedID 35482673

  • Development of a polygenic risk score to improve detection of peripheral artery disease. Vascular medicine (London, England) Wang, F., Ghanzouri, I., Leeper, N. J., Tsao, P. S., Ross, E. G. 2022: 1358863X211067564

    Abstract

    INTRODUCTION: Peripheral artery disease (PAD) is a major cause of cardiovascular morbidity and mortality, yet timely diagnosis is elusive. Larger genome-wide association studies (GWAS) have now provided the ability to evaluate whether genetic data, in the form of genome-wide polygenic risk scores (PRS), can help improve our ability to identify patients at high risk of having PAD.METHODS: Using summary statistic data from the largest PAD GWAS from the Million Veteran Program, we developed PRSs with genome data from UK Biobank. We then evaluated the clinical utility of adding the best-performing PRS to a PAD clinical risk score.RESULTS: A total of 487,320 participants (5759 PAD cases) were included in our final genetic analysis. Compared to participants in the lowest 10% of PRS, those in the highest decile had 3.1 higher odds of having PAD (95% CI, 3.06-3.21). Additionally, a PAD PRS was associated with increased risk of having coronary artery disease, congestive heart failure, and cerebrovascular disease. The PRS significantly improved a clinical risk model (Net Reclassification Index = 0.07, p < 0.001), with most of the performance seen in downgrading risk of controls. Combining clinical and genetic data to detect risk of PAD resulted in a model with an area under the curve of 0.76 (95% CI, 0.75-0.77).CONCLUSION: We demonstrate that a genome-wide PRS can discriminate risk of PAD and other cardiovascular diseases. Adding a PAD PRS to clinical risk models may help improve detection of prevalent, but undiagnosed disease.

    View details for DOI 10.1177/1358863X211067564

    View details for PubMedID 35287516

  • Genetic and clinical determinants of abdominal aortic diameter: genome-wide association studies, exome array data and Mendelian randomization study. Human molecular genetics Portilla-Fernandez, E., Klarin, D., Hwang, S., Biggs, M. L., Bis, J. C., Weiss, S., Rospleszcz, S., Natarajan, P., Hoffmann, U., Rogers, I. S., Truong, Q. A., Volker, U., Dorr, M., Bulow, R., Criqui, M. H., Allison, M., Ganesh, S. K., Yao, J., Waldenberger, M., Bamberg, F., Rice, K. M., Essers, J., Kapteijn, D. M., van der Laan, S. W., de Knegt, R. J., Ghanbari, M., Felix, J. F., Ikram, M. A., Kavousi, M., Uitterlinden, A. G., Roks, A. J., Danser, A. H., Tsao, P. S., Damrauer, S. M., Guo, X., Rotter, J. I., Psaty, B. M., Kathiresan, S., Volzke, H., Peters, A., Johnson, C., Strauch, K., Meitinger, T., O'Donnell, C. J., Dehghan, A., VA Million Veteran Program 2022

    Abstract

    Progressive dilation of the infrarenal aortic diameter is a consequence of the ageing process and is considered the main determinant of Abdominal Aortic Aneurysm (AAA). We aimed to investigate the genetic and clinical determinants of abdominal aortic diameter (AAD). We conducted a meta-analysis of genome-wide association studies in ten cohorts (n=13542) imputed to the 1000 Genome Project reference panel including 12815 subjects in the discovery phase and 727 subjects (PBIO) as replication. Maximum anterior-posterior diameter of the infrarenal aorta was used as AAD. We also included exome array data (n=14480) from seven epidemiologic studies. Single-variant and gene-based associations were done using SeqMeta package. A Mendelian randomization analysis was applied to investigate the causal effect of a number of clinical risk factors on AAD. In GWAS on AAD, rs74448815 in the intronic region of LDLRAD4 reached genome-wide significance (beta=-0.02, SE=0.004, p-value=2.10*10-8). The association replicated in the PBIO1 cohort (p-value=8.19*10-4). In exome-array single-variant analysis (p-value threshold=9*10-7), the lowest p-value was found for rs239259 located in SLC22A20 (beta=0.007, p-value =1.2*10-5). In the gene-based analysis (p-value threshold=1.85*10-6), PCSK5 showed an association with AAD (p-value=8.03*10-7). Furthermore, in Mendelian randomization analyses, we found evidence for genetic association of pulse pressure (beta=-0.003, p-value=0.02), triglycerides (beta=-0.16, p-value=0.008) and height (beta=0.03, p-value<0.0001), known risk factors for AAA, consistent with a causal association with AAD. Our findings point to new biology as well as highlighting gene regions in mechanisms that have previously been implicated in the genetics of other vascular diseases.

    View details for DOI 10.1093/hmg/ddac051

    View details for PubMedID 35234888

  • APOL1 Risk Variants, Acute Kidney Injury, and Death in Participants With African Ancestry Hospitalized With COVID-19 From the Million Veteran Program. JAMA internal medicine Hung, A. M., Shah, S. C., Bick, A. G., Yu, Z., Chen, H., Hunt, C. M., Wendt, F., Wilson, O., Greevy, R. A., Chung, C. P., Suzuki, A., Ho, Y., Akwo, E., Polimanti, R., Zhou, J., Reaven, P., Tsao, P. S., Gaziano, J. M., Huffman, J. E., Joseph, J., Luoh, S., Iyengar, S., Chang, K., Casas, J. P., Matheny, M. E., O'Donnell, C. J., Cho, K., Tao, R., Susztak, K., Robinson-Cohen, C., Tuteja, S., Siew, E. D., VA Million Veteran Program COVID-19 Science Initiative, Hung, A., Wallbom, A., Palacio, A., Robey, B., Jhala, D., Fujii, D., Cohen, D., Boyko, E., Jacono, F., Villareal, G., Garcon, H., Gaziano, J. M., Lichy, J., Norton, J., Beckham, J., Whittle, J., Huffman, J., Moser, J., Greco, J., Walsh, J., Harley, J., Wells, J., Klein, J., Moorman, J., Constans, J., Fayad, J., Casas, J. P., Xu, J., Liao, K., Alexander, K., Cho, K., Hammer, K., Oursler, K., Mattocks, K., Chang, K., Dellitalia, L., Hamner, M., Whooley, M., Murdoch, M., Gaddy, M., Godschalk, M., Rauchman, M., Huq, M., Tandon, N., Kosik, N., Ratcliffe, N., Okusaga, O., Roussos, P., Strollo, P., Meyer, P., Sriram, P., Wilson, P., Liang, P., Tsao, P. S., Balasubramanian, P., Ramoni, R., McArdle, R., Hauger, R., Servatius, R., Smith, R., Striker, R., Mathew, R., Gappy, S., Pyarajan, S., Gutierrez, S., Gupta, S., Aguayo, S., Sharma, S., Damrauer, S., Kinlay, S., Yeh, S., Luoh, S., Tuteja, S., Mastorides, S., Iyengar, S., Bhushan, S., Muralidhar, S., Ahuja, S., Liangpunsakul, S., Assimes, T., Morgan, T., Stapley, T., Sun, Y., Ballas, Z. 1800

    Abstract

    Importance: Coronavirus disease 2019 (COVID-19) confers significant risk of acute kidney injury (AKI). Patients with COVID-19 with AKI have high mortality rates.Objective: Individuals with African ancestry with 2 copies of apolipoprotein L1 (APOL1) variants G1 or G2 (high-risk group) have significantly increased rates of kidney disease. We tested the hypothesis that the APOL1 high-risk group is associated with a higher-risk of COVID-19-associated AKI and death.Design, Setting, and Participants: This retrospective cohort study included 990 participants with African ancestry enrolled in the Million Veteran Program who were hospitalized with COVID-19 between March 2020 and January 2021 with available genetic information.Exposures: The primary exposure was having 2 APOL1 risk variants (RV) (APOL1 high-risk group), compared with having 1 or 0 risk variants (APOL1 low-risk group).Main Outcomes and Measures: The primary outcome was AKI. The secondary outcomes were stages of AKI severity and death. Multivariable logistic regression analyses adjusted for preexisting comorbidities, medications, and inpatient AKI risk factors; 10 principal components of ancestry were performed to study these associations. We performed a subgroup analysis in individuals with normal kidney function prior to hospitalization (estimated glomerular filtration rate ≥60 mL/min/1.73 m2).Results: Of the 990 participants with African ancestry, 905 (91.4%) were male with a median (IQR) age of 68 (60-73) years. Overall, 392 (39.6%) patients developed AKI, 141 (14%) developed stages 2 or 3 AKI, 28 (3%) required dialysis, and 122 (12.3%) died. One hundred twenty-five (12.6%) of the participants were in the APOL1 high-risk group. Patients categorized as APOL1 high-risk group had significantly higher odds of AKI (adjusted odds ratio [OR], 1.95; 95% CI, 1.27-3.02; P=.002), higher AKI severity stages (OR, 2.03; 95% CI, 1.37-2.99; P<.001), and death (OR, 2.15; 95% CI, 1.22-3.72; P=.007). The association with AKI persisted in the subgroup with normal kidney function (OR, 1.93; 95% CI, 1.15-3.26; P=.01). Data analysis was conducted between February 2021 and April 2021.Conclusions and Relevance: In this cohort study of veterans with African ancestry hospitalized with COVID-19 infection, APOL1 kidney risk variants were associated with higher odds of AKI, AKI severity, and death, even among individuals with prior normal kidney function.

    View details for DOI 10.1001/jamainternmed.2021.8538

    View details for PubMedID 35089317

  • Leveraging cell-type-specific regulatory networks to interpret genetic variants in abdominal aortic aneurysm. Proceedings of the National Academy of Sciences of the United States of America Ma, S., Chen, X., Zhu, X., Tsao, P. S., Wong, W. H. 1800; 119 (1)

    Abstract

    Abdominal aortic aneurysm (AAA) is a common degenerative cardiovascular disease whose pathobiology is not clearly understood. The cellular heterogeneity and cell-type-specific gene regulation of vascular cells in human AAA have not been well-characterized. Here, we performed analysis of whole-genome sequencing data in AAA patients versus controls with the aim of detecting disease-associated variants that may affect gene regulation in human aortic smooth muscle cells (AoSMC) and human aortic endothelial cells (HAEC), two cell types of high relevance to AAA disease. To support this analysis, we generated H3K27ac HiChIP data for these cell types and inferred cell-type-specific gene regulatory networks. We observed that AAA-associated variants were most enriched in regulatory regions in AoSMC, compared with HAEC and CD4+ cells. The cell-type-specific regulation defined by this HiChIP data supported the importance of ERG and the KLF family of transcription factors in AAA disease. The analysis of regulatory elements that contain noncoding variants and also are differentially open between AAA patients and controls revealed the significance of the interleukin-6-mediated signaling pathway. This finding was further validated by including information from the deleteriousness effect of nonsynonymous single-nucleotide variants in AAA patients and additional control data from the Medical Genome Reference Bank dataset. These results shed important insights into AAA pathogenesis and provide a model for cell-type-specific analysis of disease-associated variants.

    View details for DOI 10.1073/pnas.2115601119

    View details for PubMedID 34930827

  • Genome-wide and phenome-wide analysis of ideal cardiovascular health in the VA Million Veteran Program. PloS one Huang, R. D., Nguyen, X. T., Peloso, G. M., Trinder, M., Posner, D. C., Aragam, K. G., Ho, Y., Lynch, J. A., Damrauer, S. M., Chang, K., Tsao, P. S., Natarajan, P., Assimes, T., Gaziano, J. M., Djousse, L., Cho, K., Wilson, P. W., Huffman, J. E., O'Donnell, C. J., Veterans Affairs Million Veteran Program 2022; 17 (5): e0267900

    Abstract

    BACKGROUND: Genetic studies may help identify causal pathways; therefore, we sought to identify genetic determinants of ideal CVH and their association with CVD outcomes in the multi-population Veteran Administration Million Veteran Program.METHODS: An ideal health score (IHS) was calculated from 3 clinical factors (blood pressure, total cholesterol, and blood glucose levels) and 3 behavioral factors (smoking status, physical activity, and BMI), ascertained at baseline. Multi-population genome-wide association study (GWAS) was performed on IHS and binary ideal health using linear and logistic regression, respectively. Using the genome-wide significant SNPs from the IHS GWAS, we created a weighted IHS polygenic risk score (PRSIHS) which was used (i) to conduct a phenome-wide association study (PheWAS) of associations between PRSIHS and ICD-9 phenotypes and (ii) to further test for associations with mortality and selected CVD outcomes using logistic and Cox regression and, as an instrumental variable, in Mendelian Randomization.RESULTS: The discovery and replication cohorts consisted of 142,404 (119,129 European American (EUR); 16,495 African American (AFR)), and 45,766 (37,646 EUR; 5,366 AFR) participants, respectively. The mean age was 65.8 years (SD = 11.2) and 92.7% were male. Overall, 4.2% exhibited ideal CVH based on the clinical and behavioral factors. In the multi-population meta-analysis, variants at 17 loci were associated with IHS and each had known GWAS associations with multiple components of the IHS. PheWAS analysis in 456,026 participants showed that increased PRSIHS was associated with a lower odds ratio for many CVD outcomes and risk factors. Both IHS and PRSIHS measures of ideal CVH were associated with significantly less CVD outcomes and CVD mortality.CONCLUSION: A set of high interest genetic variants contribute to the presence of ideal CVH in a multi-ethnic cohort of US Veterans. Genetically influenced ideal CVH is associated with lower odds of CVD outcomes and mortality.

    View details for DOI 10.1371/journal.pone.0267900

    View details for PubMedID 35613103

  • Million Veteran Program's response to COVID-19: Survey development and preliminary findings. PloS one Whitbourne, S. B., Nguyen, X. T., Song, R. J., Lord, E., Lyden, M., Harrington, K. M., Ward, R., Li, Y., Brewer, J. V., Cho, K. M., Djousse, L., Muralidhar, S., Tsao, P. S., Gaziano, J. M., Casas, J. P., MVP COVID-19 Science Program 2022; 17 (4): e0266381

    Abstract

    BACKGROUND: In response to the novel Coronavirus Disease 2019 (COVID-19) pandemic, the Department of Veterans Affairs (VA) Million Veteran Program (MVP) organized efforts to better understand the impact of COVID-19 on Veterans by developing and deploying a self-reported survey.METHODS: The MVP COVID-19 Survey was developed to collect COVID-19 specific elements including symptoms, diagnosis, hospitalization, behavioral and psychosocial factors and to augment existing MVP data with longitudinal collection of key domains in physical and mental health. Due to the rapidly evolving nature of the pandemic, a multipronged strategy was implemented to widely disseminate the COVID-19 Survey and capture data using both the online platform and mailings.RESULTS: We limited the findings of this paper to the initial phase of survey dissemination which began in May 2020. A total of 729,625 eligible MVP Veterans were invited to complete version 1 of the COVID-19 Survey. As of October 31, 2020, 58,159 surveys have been returned. The mean and standard deviation (SD) age of responders was 71 (11) years, 8.6% were female, 8.2% were Black, 5.6% were Hispanic, and 446 (0.8%) self-reported a COVID-19 diagnosis. Over 90% of responders reported wearing masks, practicing social distancing, and frequent hand washing.CONCLUSION: The MVP COVID-19 Survey provides a systematic collection of data regarding COVID-19 behaviors among Veterans and represents one of the first large-scale, national surveillance efforts of COVID-19 in the Veteran population. Continued work will examine the overall response to the survey with comparison to available VA health record data.

    View details for DOI 10.1371/journal.pone.0266381

    View details for PubMedID 35468170

  • Coronary Artery Disease Risk of Familial Hypercholesterolemia Genetic Variants Independent of Clinically Observed Longitudinal Cholesterol Exposure. Circulation. Genomic and precision medicine Clarke, S. L., Tcheandjieu, C., Hilliard, A. T., Lee, M., Lynch, J., Chang, K. M., Miller, D., Knowles, J. W., O'Donnell, C., Tsao, P., Rader, D. J., Wilson, P. W., Sun, Y. V., Gaziano, M., Assimes, T. L. 2022: CIRCGEN121003501

    Abstract

    Familial hypercholesterolemia (FH) genetic variants confer risk for coronary artery disease independent of LDL-C (low-density lipoprotein cholesterol) when considering a single measurement. In real clinical settings, longitudinal LDL-C data are often available through the electronic health record. It is unknown whether genetic testing for FH variants provides additional risk-stratifying information once longitudinal LDL-C is considered.We used the extensive electronic health record data available through the Million Veteran Program to conduct a nested case-control study. The primary outcome was coronary artery disease, derived from electronic health record codes for acute myocardial infarction and coronary revascularization. Incidence density sampling was used to match case/control exposure windows, defined by the date of the first LDL-C measurement to the date of the first coronary artery disease code of the index case. Adjustments for the first, maximum, or mean LDL-C were analyzed. FH variants in LDLR, APOB, and PCSK9 were assessed by custom genotype array.In a cohort of 23 091 predominantly prevalent cases at enrollment and 230 910 matched controls, FH variant carriers had an increased risk for coronary artery disease (odds ratio [OR], 1.53 [95% CI, 1.24-1.89]). Adjusting for mean LDL-C led to the greatest attenuation of the risk estimate, but significant risk remained (odds ratio, 1.33 [95% CI, 1.08-1.64]). The degree of attenuation was not affected by the number and the spread of LDL-C measures available.The risk associated with carrying an FH variant cannot be fully captured by the LDL-C data available in the electronic health record, even when considering multiple LDL-C measurements spanning more than a decade.

    View details for DOI 10.1161/CIRCGEN.121.003501

    View details for PubMedID 35143253

  • Preoperative Computed Tomography Angiography Reveals Leaflet-Specific Calcification and Excursion Patterns in Aortic Stenosis. Circulation. Cardiovascular imaging Chen, I. Y., Vedula, V., Malik, S. B., Liang, T., Chang, A. Y., Chung, K. S., Sayed, N., Tsao, P. S., Giacomini, J. C., Marsden, A. L., Wu, J. C. 1800: CIRCIMAGING121012884

    Abstract

    BACKGROUND: Computed tomography-based evaluation of aortic stenosis (AS) by calcium scoring does not consider interleaflet differences in leaflet characteristics. Here, we sought to examine the functional implications of these differences.METHODS: We retrospectively reviewed the computed tomography angiograms of 200 male patients with degenerative calcific AS undergoing transcatheter aortic valve replacement and 20 male patients with normal aortic valves. We compared the computed tomography angiography (CTA)-derived aortic valve leaflet calcification load (AVLCCTA), appearance, and systolic leaflet excursion (LEsys) of individual leaflets. We performed computer simulations of normal valves to investigate how interleaflet differences in LEsys affect aortic valve area. We used linear regression to identify predictors of leaflet-specific calcification in patients with AS.RESULTS: In patients with AS, the noncoronary cusp (NCC) carried the greatest AVLCCTA (365.9 [237.3-595.4] Agatston unit), compared to the left coronary cusp (LCC, 278.5 [169.2-478.8] Agatston unit) and the right coronary cusp (RCC, 240.6 [137.3-439.0] Agatston unit; both P<0.001). However, LCC conferred the least LEsys (42.8 [38.8-49.0]) compared to NCC (44.8 [41.1-49.78], P=0.001) and RCC (47.7 [42.0-52.3], P<0.001) and was more often characterized as predominantly thickened (23.5%) compared to NCC (12.5%) and RCC (16.5%). Computer simulations of normal valves revealed greater reductions in aortic valve area following closures of NCC (-32.2 [-38.4 to -25.8]%) and RCC (-35.7 [-40.2 to -32.9]%) than LCC (-24.5 [-28.5 to -18.3]%; both P<0.001). By linear regression, the AVLCCTA of NCC and RCC, but not LCC, predicted LEsys (both P<0.001) in patients with AS. Both ostial occlusion and ostial height of the right coronary artery predicted AVLCCTA, RCC (P=0.005 and P=0.001).CONCLUSIONS: In male patients, the AVLCCTA of NCC and RCC contribute more to AS than that of LCC. LCC's propensity for noncalcific leaflet thickening and worse LEsys, however, should not be underestimated when using calcium scores to assess AS severity.

    View details for DOI 10.1161/CIRCIMAGING.121.012884

    View details for PubMedID 34915729

  • Trellis for efficient data and task management in the VA Million Veteran Program. Scientific reports Ross, P. B., Song, J., Tsao, P. S., Pan, C. 2021; 11 (1): 23229

    Abstract

    Biomedical studies have become larger in size and yielded large quantities of data, yet efficient data processing remains a challenge. Here we present Trellis, a cloud-based data and task management framework that completely automates the process from data ingestion to result presentation, while tracking data lineage, facilitating information query, and supporting fault-tolerance and scalability. Using a graph database to coordinate the state of the data processing workflows and a scalable microservice architecture to perform bioinformatics tasks, Trellis has enabled efficient variant calling on 100,000 human genomes collected in the VA Million Veteran Program.

    View details for DOI 10.1038/s41598-021-02569-5

    View details for PubMedID 34853358

  • A Phenome-Wide Association Study of genes associated with COVID-19 severity reveals shared genetics with complex diseases in the Million Veteran Program. medRxiv : the preprint server for health sciences Verma, A., Tsao, N., Thomann, L., Ho, Y. L., Iyengar, S., Luoh, S. W., Carr, R., Crawford, D., Efird, J. T., Huffman, J., Hung, A., Ivey, K., Levin, M., Lynch, J., Natarajan, P., Pyarajan, S., Bick, A., Costa, L., Genovese, G., Hauger, R., Madduri, R., Pathak, G., Polimanti, R., Voight, B., Vujkovic, M., Zekavat, M., Zhao, H., Ritchie, M. D., Chang, K. M., Cho, K., Casas, J. P., Tsao, P. S., Gaziano, J. M., O'Donnell, C., Damrauer, S., Liao, K. 2021

    Abstract

    The study aims to determine the shared genetic architecture between COVID-19 severity with existing medical conditions using electronic health record (EHR) data. We conducted a Phenome-Wide Association Study (PheWAS) of genetic variants associated with critical illness (n=35) or hospitalization (n=42) due to severe COVID-19 using genome-wide association summary from the Host Genetics Initiative. PheWAS analysis was performed using genotype-phenotype data from the Veterans Affairs Million Veteran Program (MVP). Phenotypes were defined by International Classification of Diseases (ICD) codes mapped to clinically relevant groups using published PheWAS methods. Among 658,582 Veterans, variants associated with severe COVID-19 were tested for association across 1,559 phenotypes. Variants at the ABO locus (rs495828, rs505922) associated with the largest number of phenotypes (nrs495828=53 and nrs505922=59); strongest association with venous embolism, odds ratio (ORrs495828 1.33 (p=1.32 × 10-199), and thrombosis ORrs505922 1.33, p=2.2 × 10-265. Among 67 respiratory conditions tested, 11 had significant associations including MUC5B locus (rs35705950) with increased risk of idiopathic fibrosing alveolitis OR 2.83, p=4.12 × 10-191; CRHR1 (rs61667602) associated with reduced risk of pulmonary fibrosis, OR 0.84, p=2.26 × 10-12. The TYK2 locus (rs11085727) associated with reduced risk for autoimmune conditions, e.g., psoriasis OR 0.88, p=6.48 × 10-23, lupus OR 0.84, p=3.97 × 10-06. PheWAS stratified by genetic ancestry demonstrated differences in genotype-phenotype associations across ancestry. LMNA (rs581342) associated with neutropenia OR 1.29 p=4.1 × 10-13 among Veterans of African ancestry but not European. Overall, we observed a shared genetic architecture between COVID-19 severity and conditions related to underlying risk factors for severe and poor COVID-19 outcomes. Differing associations between genotype-phenotype across ancestries may inform heterogenous outcomes observed with COVID-19. Divergent associations between risk for severe COVID-19 with autoimmune inflammatory conditions both respiratory and non-respiratory highlights the shared pathways and fine balance of immune host response and autoimmunity and caution required when considering treatment targets.

    View details for DOI 10.1101/2021.05.18.21257396

    View details for PubMedID 34642702

    View details for PubMedCentralID PMC8509103

  • A GENOME-WIDE ASSOCIATION STUDY OF CHRONIC ALT-BASED NAFLD IN THE MILLION VETERAN PROGRAM WITH HISTOLOGICAL AND RADIOLOGICAL VALIDATION Vujkovic, M., Ramdas, S., Lorenz, K. M., Guo, X., Darlay, R., Cordell, H. J., He, J., Gindin, Y., Chung, C., Myers, R. P., Schneider, C., Park, J., Lee, K., Serper, M., Carr, R. M., Kaplan, D. E., Haas, M., MacLean, M., Witschey, W., Zhu, X., Tcheandjieu, C., Kember, R. L., Kranzler, H. R., Verma, A., Giri, A., Klarin, D. M., Sun, Y. V., Huang, J., Huffman, J., Creasy, K., Hand, N. J., Liu, C., Long, M., Yao, J., Li, X., Budoff, M., Tan, J., Lin, H. J., Chen, Y., Taylor, K., Chang, R., Krauss, R., Vilarinho, S. M., Brancale, J., Nielsen, J., Locke, A. E., Verweij, N., Jones, M. B., Baras, A., Reddy, K., Neuschwander-Tetri, B. A., Schwimmer, J., Sanyal, A. J., Chalasani, N. P., Ryan, K. A., Mitchell, B. D., Gill, D., Wells, A., Manduchi, E., Saiman, Y., Mahmud, N., Miller, D. R., Reaven, P. D., Phillips, L. S., Muralidhar, S., DuVall, S. L., Lee, J. S., Assimes, T. L., Pyarajan, S., Cho, K., Edwards, T. L., Damrauer, S. M., Wilson, P. F., Gaziano, J., O'Donnell, C. J., Khera, A., Grant, S., Brown, C. D., Tsao, P., Saleheen, D., Lotta, L., Bastarache, L., Anstee, Q. M., Daly, A. K., Meigs, J. B., Rotter, J. I., Lynch, J. A., Rader, D. J., Voight, B. F., Chang, K., Regeneron Genetics Center, DiscovEHR Collaboration WILEY. 2021: 6A-7A
  • A Missense Variant in the IL-6 Receptor and Protection from Peripheral Artery Disease. Circulation research Levin, M. G., Klarin, D., Georgakis, M. K., Lynch, J., Liao, K. P., Voight, B. F., O'Donnell, C. J., Chang, K., Assimes, T. L., Tsao, P. S., Damrauer, S. M. 2021

    View details for DOI 10.1161/CIRCRESAHA.121.319589

    View details for PubMedID 34547901

  • peri-Adventitial delivery of smooth muscle cells in porous collagen scaffolds for treatment of experimental abdominal aortic aneurysm. Biomaterials science Mulorz, J., Shayan, M., Hu, C., Alcazar, C., Chan, A. H., Briggs, M., Wen, Y., Walvekar, A. P., Ramasubramanian, A. K., Spin, J. M., Chen, B., Tsao, P. S., Huang, N. F. 2021

    Abstract

    Abdominal aortic aneurysm (AAA) is associated with the loss of vascular smooth muscle cells (SMCs) within the vessel wall. Direct delivery of therapeutic cells is challenging due to impaired mechanical integrity of the vessel wall. We hypothesized that porous collagen scaffolds can be an effective vehicle for the delivery of human-derived SMCs to the site of AAA. The purpose was to evaluate if the delivery of cell-seeded scaffolds can abrogate progressive expansion in a mouse model of AAA. Collagen scaffolds seeded with either primary human aortic SMCs or induced pluripotent stem cell derived-smooth muscle progenitor cells (iPSC-SMPs) had >80% in vitro cell viability and >75% cell penetrance through the scaffold's depth, while preserving smooth muscle phenotype. The cell-seeded scaffolds were successfully transplanted onto the murine aneurysm peri-adventitia on day 7 following AAA induction using pancreatic porcine elastase infusion. Ultrasound imaging revealed that SMC-seeded scaffolds significantly reduced the aortic diameter by 28 days, compared to scaffolds seeded with iPSC-SMPs or without cells (acellular scaffold), respectively. Bioluminescence imaging demonstrated that both cell-seeded scaffold groups had cellular localization to the aneurysm but a decline in survival with time. Histological analysis revealed that both cell-seeded scaffold groups had more SMC retention and less macrophage invasion into the medial layer of AAA lesions, when compared to the acellular scaffold treatment group. Our data suggest that scaffold-based SMC delivery is feasible and may constitute a platform for cell-based AAA therapy.

    View details for DOI 10.1039/d1bm00685a

    View details for PubMedID 34522940

  • Dissecting the Shared Genetic Architecture of Suicide Attempt, Psychiatric Disorders, and Known Risk Factors. Biological psychiatry Mullins, N., Kang, J., Campos, A. I., Coleman, J. R., Edwards, A. C., Galfalvy, H., Levey, D. F., Lori, A., Shabalin, A., Starnawska, A., Su, M., Watson, H. J., Adams, M., Awasthi, S., Gandal, M., Hafferty, J. D., Hishimoto, A., Kim, M., Okazaki, S., Otsuka, I., Ripke, S., Ware, E. B., Bergen, A. W., Berrettini, W. H., Bohus, M., Brandt, H., Chang, X., Chen, W. J., Chen, H., Crawford, S., Crow, S., DiBlasi, E., Duriez, P., Fernandez-Aranda, F., Fichter, M. M., Gallinger, S., Glatt, S. J., Gorwood, P., Guo, Y., Hakonarson, H., Halmi, K. A., Hwu, H., Jain, S., Jamain, S., Jimenez-Murcia, S., Johnson, C., Kaplan, A. S., Kaye, W. H., Keel, P. K., Kennedy, J. L., Klump, K. L., Li, D., Liao, S., Lieb, K., Lilenfeld, L., Liu, C., Magistretti, P. J., Marshall, C. R., Mitchell, J. E., Monson, E. T., Myers, R. M., Pinto, D., Powers, A., Ramoz, N., Roepke, S., Rozanov, V., Scherer, S. W., Schmahl, C., Sokolowski, M., Strober, M., Thornton, L. M., Treasure, J., Tsuang, M. T., Witt, S. H., Woodside, D. B., Yilmaz, Z., Zillich, L., Adolfsson, R., Agartz, I., Air, T. M., Alda, M., Alfredsson, L., Andreassen, O. A., Anjorin, A., Appadurai, V., Soler Artigas, M., Van der Auwera, S., Azevedo, M. H., Bass, N., Bau, C. H., Baune, B. T., Bellivier, F., Berger, K., Biernacka, J. M., Bigdeli, T. B., Binder, E. B., Boehnke, M., Boks, M. P., Bosch, R., Braff, D. L., Bryant, R., Budde, M., Byrne, E. M., Cahn, W., Casas, M., Castelao, E., Cervilla, J. A., Chaumette, B., Cichon, S., Corvin, A., Craddock, N., Craig, D., Degenhardt, F., Djurovic, S., Edenberg, H. J., Fanous, A. H., Foo, J. C., Forstner, A. J., Frye, M., Fullerton, J. M., Gatt, J. M., Gejman, P. V., Giegling, I., Grabe, H. J., Green, M. J., Grevet, E. H., Grigoroiu-Serbanescu, M., Gutierrez, B., Guzman-Parra, J., Hamilton, S. P., Hamshere, M. L., Hartmann, A., Hauser, J., Heilmann-Heimbach, S., Hoffmann, P., Ising, M., Jones, I., Jones, L. A., Jonsson, L., Kahn, R. S., Kelsoe, J. R., Kendler, K. S., Kloiber, S., Koenen, K. C., Kogevinas, M., Konte, B., Krebs, M., Landen, M., Lawrence, J., Leboyer, M., Lee, P. H., Levinson, D. F., Liao, C., Lissowska, J., Lucae, S., Mayoral, F., McElroy, S. L., McGrath, P., McGuffin, P., McQuillin, A., Medland, S. E., Mehta, D., Melle, I., Milaneschi, Y., Mitchell, P. B., Molina, E., Morken, G., Mortensen, P. B., Muller-Myhsok, B., Nievergelt, C., Nimgaonkar, V., Nothen, M. M., O'Donovan, M. C., Ophoff, R. A., Owen, M. J., Pato, C., Pato, M. T., Penninx, B. W., Pimm, J., Pistis, G., Potash, J. B., Power, R. A., Preisig, M., Quested, D., Ramos-Quiroga, J. A., Reif, A., Ribases, M., Richarte, V., Rietschel, M., Rivera, M., Roberts, A., Roberts, G., Rouleau, G. A., Rovaris, D. L., Rujescu, D., Sanchez-Mora, C., Sanders, A. R., Schofield, P. R., Schulze, T. G., Scott, L. J., Serretti, A., Shi, J., Shyn, S. I., Sirignano, L., Sklar, P., Smeland, O. B., Smoller, J. W., Sonuga-Barke, E. J., Spalletta, G., Strauss, J. S., Swiatkowska, B., Trzaskowski, M., Turecki, G., Vilar-Ribo, L., Vincent, J. B., Volzke, H., Walters, J. T., Shannon Weickert, C., Weickert, T. W., Weissman, M. M., Williams, L. M., Wray, N. R., Zai, C. C., Ashley-Koch, A. E., Beckham, J. C., Hauser, E. R., Hauser, M. A., Kimbrel, N. A., Lindquist, J. H., McMahon, B., Oslin, D. W., Qin, X., Major Depressive Disorder Working Group of the Psychiatric Genomics Consortium, Bipolar Disorder Working Group of the Psychiatric Genomics Consortium, Eating Disorders Working Group of the Psychiatric Genomics Consortium, German Borderline Genomics Consortium, MVP Suicide Exemplar Workgroup, VA Million Veteran Program, Agerbo, E., Borglum, A. D., Breen, G., Erlangsen, A., Esko, T., Gelernter, J., Hougaard, D. M., Kessler, R. C., Kranzler, H. R., Li, Q. S., Martin, N. G., McIntosh, A. M., Mors, O., Nordentoft, M., Olsen, C. M., Porteous, D., Ursano, R. J., Wasserman, D., Werge, T., Whiteman, D. C., Bulik, C. M., Coon, H., Demontis, D., Docherty, A. R., Kuo, P., Lewis, C. M., Mann, J. J., Renteria, M. E., Smith, D. J., Stahl, E. A., Stein, M. B., Streit, F., Willour, V., Ruderfer, D. M., Wray, N. R., Ripke, S., Mattheisen, M., Trzaskowski, M., Byrne, E. M., Abdellaoui, A., Adams, M. J., Agerbo, E., Air, T. M., Andlauer, T. F., Bacanu, S., Bakvad-Hansen, M., Beekman, A. T., Bigdeli, T. B., Binder, E. B., Bryois, J., Buttenschon, H. N., Bybjerg-Grauholm, J., Cai, N., Castelao, E., Christensen, J. H., Clarke, T., Coleman, J. R., Colodro-Conde, L., Couvy-Duchesne, B., Craddock, N., Crawford, G. E., Davies, G., Degenhardt, F., Derks, E. M., Direk, N., Dolan, C. V., Dunn, E. C., Eley, T. C., Escott-Price, V., Hassan Kiadeh, F. F., Finucane, H. K., Foo, J. C., Forstner, A. J., Frank, J., Gaspar, H. A., Gill, M., Goes, F. S., Gordon, S. D., Weinsheimer, S. M., Wellmann, J., Willemsen, G., Witt, S. H., Wu, Y., Xi, H. S., Yang, J., Zhang, F., Arolt, V., Baune, B. T., Berger, K., Boomsma, D. I., Cichon, S., Dannlowski, U., de Geus, E. J., Depaulo, J. R., Domenici, E., Domschke, K., Esko, T., Grabe, H. J., Hamilton, S. P., Grove, J., Hall, L. S., Hansen, C. S., Hansen, T. F., Herms, S., Hickie, I. B., Hoffmann, P., Homuth, G., Horn, C., Hottenga, J., Hougaard, D. M., Howard, D. M., Ising, M., Jansen, R., Jones, I., Jones, L. A., Jorgenson, E., Knowles, J. A., Kohane, I. S., Kraft, J., Kretzschmar, W. W., Kutalik, Z., Li, Y., Lind, P. A., MacIntyre, D. J., MacKinnon, D. F., Maier, R. M., Maier, W., Marchini, J., Mbarek, H., McGrath, P., McGuffin, P., Medland, S. E., Mehta, D., Middeldorp, C. M., Mihailov, E., Milaneschi, Y., Milani, L., Mondimore, F. M., Montgomery, G. W., Mostafavi, S., Mullins, N., Nauck, M., Ng, B., Nivard, M. G., Nyholt, D. R., O'Reilly, P. F., Oskarsson, H., Hayward, C., Heath, A. C., Kendler, K. S., Kloiber, S., Lewis, G., Li, Q. S., Lucae, S., Madden, P. A., Magnusson, P. K., Martin, N. G., McIntosh, A. M., Metspalu, A., Mors, O., Mortensen, P. B., Muller-Myhsok, B., Nordentoft, M., Nothen, M. M., O'Donovan, M. C., Paciga, S. A., Pedersen, N. L., Owen, M. J., Painter, J. N., Pedersen, C. B., Pedersen, M. G., Peterson, R. E., Peyrot, W. J., Pistis, G., Posthuma, D., Quiroz, J. A., Qvist, P., Rice, J. P., Riley, B. P., Rivera, M., Mirza, S. S., Schoevers, R., Schulte, E. C., Shen, L., Shi, J., Shyn, S. I., Sigurdsson, E., Sinnamon, G. C., Smit, J. H., Smith, D. J., Stefansson, H., Steinberg, S., Streit, F., Strohmaier, J., Tansey, K. E., Teismann, H., Teumer, A., Thompson, W., Thomson, P. A., Thorgeirsson, T. E., Traylor, M., Treutlein, J., Trubetskoy, V., Uitterlinden, A. G., Umbricht, D., der Auwera, S. V., van Hemert, A. M., Viktorin, A., Visscher, P. M., Wang, Y., Webb, B. T., Penninx, B. W., Perlis, R. H., Porteous, D. J., Potash, J. B., Preisig, M., Rietschel, M., Schaefer, C., Schulze, T. G., Smoller, J. W., Stefansson, K., Tiemeier, H., Uher, R., Volzke, H., Weissman, M. M., Werge, T., Lewis, C. M., Levinson, D. F., Breen, G., Borglum, A. D., Sullivan, P. F., Mullins, N., Forstner, A. J., O'Connell, K. S., Coombes, B., Coleman, J. R., Qiao, Z., Als, T. D., Bigdeli, T. B., Borte, S., Bryois, J., Charney, A. W., Drange, O. K., Gandal, M. J., Hagenaars, S. P., Ikeda, M., Kamitaki, N., Kim, M., Krebs, K., Panagiotaropoulou, G., Schilder, B. M., Sloofman, L. G., Steinberg, S., Trubetskoy, V., Winsvold, B. S., Won, H., Abramova, L., Adorjan, K., Agerbo, E., Al Eissa, M., Albani, D., Alliey-Rodriguez, N., Anjorin, A., Antilla, V., Antoniou, A., Awasthi, S., Baek, J. H., Bakvad-Hansen, M., Bass, N., Bauer, M., Beins, E. C., Bergen, S. E., Birner, A., Pedersen, C. B., Boen, E., Boks, M. P., Bosch, R., Brum, M., Brumpton, B. M., Brunkhorst-Kanaan, N., Budde, M., Bybjerg-Grauholm, J., Byerley, W., Cairns, M., Casas, M., Cervantes, P., Clarke, T., Cruceanu, C., Cuellar-Barboza, A., Cunningham, J., Curtis, D., Czerski, P. M., Dale, A. M., Dalkner, N., David, F. S., Degenhardt, F., Djurovic, S., Dobbyn, A. L., Douzenis, A., Elvsashagen, T., Escott-Price, V., Ferrier, I. N., Fiorentino, A., Foroud, T. M., Forty, L., Frank, J., Frei, O., Freimer, N. B., Frisen, L., Gade, K., Garnham, J., Gelernter, J., Pedersen, M. G., Gizer, I. R., Gordon, S. D., Gordon-Smith, K., Greenwood, T. A., Grove, J., Guzman-Parra, J., Ha, K., Haraldsson, M., Hautzinger, M., Heilbronner, U., Hellgren, D., Herms, S., Hoffmann, P., Holmans, P. A., Huckins, L., Jamain, S., Johnson, J. S., Kalman, J. L., Kamatani, Y., Kennedy, J. L., Kittel-Schneider, S., Knowles, J. A., Kogevinas, M., Koromina, M., Kranz, T. M., Kranzler, H. R., Kubo, M., Kupka, R., Kushner, S. A., Lavebratt, C., Lawrence, J., Leber, M., Lee, H., Lee, P. H., Levy, S. 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B., Morken, G., Mors, O., Mortensen, P. B., Mowry, B., Muller-Myhsok, B., Myers, R. M., Neale, B. M., Nievergelt, C. M., Nordentoft, M., Nothen, M. M., O'Donovan, M. C., Oedegaard, K. J., Olsson, T., Owen, M. J., Paciga, S. A., Pantelis, C., Pato, C., Pato, M. T., Patrinos, G. P., Perlis, R. H., Posthuma, D., Ramos-Quiroga, J. A., Reif, A., Reininghaus, E. Z., Ribases, M., Rietschel, M., Ripke, S., Rouleau, G. A., Saito, T., Schall, U., Schalling, M., Schofield, P. R., Schulze, T. G., Scott, L. J., Scott, R. J., Serretti, A., Weickert, C. S., Smoller, J. W., Stefansson, H., Stefansson, K., Stordal, E., Streit, F., Sullivan, P. F., Turecki, G., Vaaler, A. E., Vieta, E., Vincent, J. B., Waldman, I. D., Weickert, T. W., Werge, T., Wray, N. R., Zwart, J., Biernacka, J. M., Nurnberger, J. I., Cichon, S., Edenberg, H. J., Stahl, E. A., McQuillin, A., Di Florio, A., Ophoff, R. A., Andreassen, O. A., Adan, R. A., Alfredsson, L., Ando, T., Andreassen, O. A., Aschauer, H., Baker, J. H., Bencko, V., Bergen, A. W., Berrettini, W. H., Birgegard, A., Boden, J. M., Boehm, I., Boni, C., Perica, V. B., Brandt, H., Breen, G., Bryois, J., Buehren, K., Bulik, C. M., Burghardt, R., Carlberg, L., Cassina, M., Cichon, S., Clementi, M., Coleman, J. R., Cone, R. D., Courtet, P., Crawford, S., Crow, S., Crowley, J. J., Danner, U. N., Davis, O. S., de Zwaan, M., Dedoussis, G., Degortes, D., DeSocio, J. E., Dick, D. M., Dikeos, D., Dina, C., Dmitrzak-Weglarz, M., Martinez, E. D., Duncan, L. E., Egberts, K., Marshall, C. R., Martin, N. G., Mattheisen, M., Mattingsdal, M., McDevitt, S., McGuffin, P., Medland, S. E., Metspalu, A., Meulenbelt, I., Micali, N., Mitchell, J., Mitchell, K., Monteleone, P., Monteleone, A. M., Montgomery, G. W., Mortensen, P. B., Munn-Chernoff, M. A., Nacmias, B., Navratilova, M., Ntalla, I., Olsen, C. M., Ophoff, R. A., O'Toole, J. K., Padyukov, L., Palotie, A., Pantel, J., Papezova, H., Parker, R., Pearson, J. F., Pedersen, N. L., Ehrlich, S., Escaramis, G., Esko, T., Espeseth, T., Estivill, X., Farmer, A., Favaro, A., Fernandez-Aranda, F., Fichter, M. M., Fischer, K., Floyd, J. A., Focker, M., Foretova, L., Forstner, A. J., Forzan, M., Franklin, C. S., Gallinger, S., Gambaro, G., Gaspar, H. A., Giegling, I., Giuranna, J., Giusti-Rodriquez, P., Gonidakis, F., Gordon, S., Gorwood, P., Mayora, M. G., Grove, J., Guillaume, S., Guo, Y., Hakonarson, H., Halmi, K. A., Hanscombe, K. B., Hatzikotoulas, K., Hauser, J., Hebebrand, J., Helder, S. G., Henders, A. K., Herms, S., Herpertz-Dahlmann, B., Herzog, W., Hinney, A., Horwood, L. J., Hubel, C., Petersen, L. V., Pinto, D., Purves, K. L., Raevuori, A., Ramoz, N., Reichborn-Kjennerud, T., Ricca, V., Ripatti, S., Ripke, S., Ritschel, F., Roberts, M., Rujescu, D., Rybakowski, F., Santonastaso, P., Scherag, A., Scherer, S. W., Schmidt, U., Schork, N. J., Schosser, A., Seitz, J., Slachtova, L., Slagboom, P. E., Slof-Op 't Landt, M. C., Slopien, A., Soranzo, N., Sorbi, S., Southam, L., Steen, V. W., Strober, M., Huckins, L. M., Hudson, J. I., Imgart, H., Inoko, H., Janout, V., Jimenez-Murcia, S., Johnson, C., Jordan, J., Julia, A., Kalsi, G., Kaminska, D., Kaplan, A. S., Kaprio, J., Karhunen, L., Karwautz, A., Kas, M. J., Kaye, W. H., Kennedy, J. L., Kennedy, M. A., Keski-Rahkonen, A., Kiezebrink, K., Kim, Y., Kirk, K. M., Klareskog, L., Klump, K. L., Knudsen, G. P., Landen, M., Larsen, J. T., Le Hellard, S., Leppa, V. M., Li, D., Lichtenstein, P., Lilenfeld, L., Lin, B. D., Lissowska, J., Lundervold, A., Luykx, J., Magistretti, P. J., Maj, M., Mannik, K., Marsal, S., Stuber, G. D., Sullivan, P. F., Swiatkowska, B., Szatkiewicz, J. P., Tachmazidou, I., Tenconi, E., Thornton, L. M., Tortorella, A., Tozzi, F., Treasure, J., Tsitsika, A., Tyszkiewicz-Nwafor, M., Tziouvas, K., van Elburg, A. A., van Furth, E. F., Wade, T. D., Wagner, G., Walton, E., Watson, H. J., Werge, T., Whiteman, D. C., Wichmann, H. E., Widen, E., Woodside, D. B., Yao, S., Yilmaz, Z., Zeggini, E., Zerwas, S., Zipfel, S., Witt, S. H., Streit, F., Jungkunz, M., Frank, J., Awasthi, S., Treutlein, J., Dietl, L., Schwarze, C. E., Dahmen, N., Schott, B. H., Nothen, M. M., Ripke, S., Mobascher, A., Rujescu, D., Lieb, K., Roepke, S., Schmahl, C., Bohus, M., Rietschel, M., Crivelli, S., Dennis, M. F., Harvey, P. D., Carter, B. W., Huffman, J. E., Jacobson, D., Madduri, R., Olsen, M. K., Pestian, J., Gaziano, J. M., Muralidhar, S., Ramoni, R., Beckham, J., Chang, K., O'Donnell, C. J., Tsao, P. S., Breeling, J., Huang, G., Romero, J. P., Muralidhar, S., Moser, J., Whitbourne, S. B., Brewer, J. V., Aslan, M., Connor, T., Argyres, D. P., Tsao, P. S., Gaziano, J. M., Stephens, B., Brophy, M. T., Humphries, D. E., Selva, L. E., Do, N., Shayan, S., Cho, K., O'Donnell, C. J., O'Donnell, C. J., Pyarajan, S., Tsao, P. S., Cho, K., Pyarajan, S., Hauser, E., Sun, Y., Zhao, H., Wilson, P., McArdle, R., Dellitalia, L., Mattocks, K., Harley, J., Zablocki, C. J., Whittle, J., Jacono, F., Beckham, J., Gutierrez, S., Gibson, G., Hammer, K., Kaminsky, L., Villareal, G., Kinlay, S., Xu, J., Hamner, M., Mathew, R., Bhushan, S., Iruvanti, P., Godschalk, M., Ballas, Z., Ivins, D., Mastorides, S., Moorman, J., Gappy, S., Klein, J., Ratcliffe, N., Florez, H., Okusaga, O., Murdoch, M., Sriram, P., Yeh, S. S., Tandon, N., Jhala, D., Aguayo, S., Cohen, D., Sharma, S., Liangpunsakul, S., Oursler, K. A., Whooley, M., Ahuja, S., Constans, J., Meyer, P., Greco, J., Rauchman, M., Servatius, R., Gaddy, M., Wallbom, A., Morgan, T., Stapley, T., Sherman, S., Ross, G., Tsao, P., Strollo, P. J., Boyko, E., Meyer, L., Gupta, S., Huq, M., Fayad, J., Hung, A., Lichy, J., Hurley, R., Robey, B., Striker, R. 2021

    Abstract

    BACKGROUND: Suicide is a leading cause of death worldwide, and nonfatal suicide attempts, which occur far more frequently, are a major source of disability and social and economic burden. Both have substantial genetic etiology, which is partially shared and partially distinct from that of related psychiatric disorders.METHODS: We conducted a genome-wide association study (GWAS) of 29,782 suicide attempt (SA) cases and 519,961 controls in the International Suicide Genetics Consortium (ISGC). The GWAS of SA was conditioned on psychiatric disorders using GWAS summary statistics via multitrait-based conditional and joint analysis, to remove genetic effects on SA mediated by psychiatric disorders. We investigated the shared and divergent genetic architectures of SA, psychiatric disorders, and other known risk factors.RESULTS: Two loci reached genome-wide significance for SA: the major histocompatibility complex and an intergenic locus on chromosome 7, the latter of which remained associated with SA after conditioning on psychiatric disorders and replicated in an independent cohort from the Million Veteran Program. This locus has been implicated in risk-taking behavior, smoking, and insomnia. SA showed strong genetic correlation with psychiatric disorders, particularly major depression, and also with smoking, pain, risk-taking behavior, sleep disturbances, lower educational attainment, reproductive traits, lower socioeconomic status, and poorer general health. After conditioning on psychiatric disorders, the genetic correlations between SA and psychiatric disorders decreased, whereas those with nonpsychiatric traits remained largely unchanged.CONCLUSIONS: Our results identify a risk locus that contributes more strongly to SA than other phenotypes and suggest a shared underlying biology between SA and known risk factors that is not mediated by psychiatric disorders.

    View details for DOI 10.1016/j.biopsych.2021.05.029

    View details for PubMedID 34861974

  • Regulatory variants in TCF7L2 are associated with thoracic aortic aneurysm. American journal of human genetics Roychowdhury, T., Lu, H., Hornsby, W. E., Crone, B., Wang, G. T., Guo, D., Sendamarai, A. K., Devineni, P., Lin, M., Zhou, W., Graham, S. E., Wolford, B. N., Surakka, I., Wang, Z., Chang, L., Zhang, J., Mathis, M., Brummett, C. M., Melendez, T. L., Shea, M. J., Kim, K. M., Deeb, G. M., Patel, H. J., Eliason, J., Eagle, K. A., Yang, B., Ganesh, S. K., Brumpton, B., Asvold, B. O., Skogholt, A. H., Hveem, K., VA Million Veteran Program, Pyarajan, S., Klarin, D., Tsao, P. S., Damrauer, S. M., Leal, S. M., Milewicz, D. M., Chen, Y. E., Garcia-Barrio, M. T., Willer, C. J. 2021

    Abstract

    Thoracic aortic aneurysm (TAA) is characterized by dilation of the aortic root or ascending/descending aorta. TAA is a heritable disease that can be potentially life threatening. While 10%-20% of TAA cases are caused by rare, pathogenic variants in single genes, the origin of the majority of TAA cases remains unknown. A previous study implicated common variants in FBN1 with TAA disease risk. Here, we report a genome-wide scan of 1,351 TAA-affected individuals and 18,295 control individuals from the Cardiovascular Health Improvement Project and Michigan Genomics Initiative at the University of Michigan. We identified a genome-wide significant association with TAA for variants within the third intron of TCF7L2 following replication with meta-analysis of four additional independent cohorts. Common variants in this locus are the strongest known genetic risk factor for type 2 diabetes. Although evidence indicates the presence of different causal variants for TAA and type 2 diabetes at this locus, we observed an opposite direction of effect. The genetic association for TAA colocalizes with an aortic eQTL of TCF7L2, suggesting a functional relationship. These analyses predict an association of higher expression of TCF7L2 with TAA disease risk. Invitro, we show that upregulation of TCF7L2 is associated with BCL2 repression promoting vascular smooth muscle cell apoptosis, a key driver of TAA disease.

    View details for DOI 10.1016/j.ajhg.2021.06.016

    View details for PubMedID 34265237

  • Nicotine Affects Murine Aortic Stiffness and Fatigue Response During Supraphysiological Cycling. Journal of biomechanical engineering Ho, E., Mulorz, J., Wong, J., Wagenhauser, M. U., Tsao, P., Ramasubramanian, A. K., Lee, S. J. 2021

    Abstract

    Nicotine exposure is a major risk factor for several cardiovascular diseases. Although the deleterious effects of nicotine on aortic remodeling processes have been studied to some extent, the biophysical consequences are not fully elucidated. In this investigation, we applied quasi-static and dynamic loading to quantify ways in which exposure to nicotine affects mechanical behavior of murine arterial tissue. Segments of thoracic aortas from C57BL/6 mice exposed to 25 mg/kg/day of subcutaneous nicotine for 28 days were subjected to uniaxial tensile loading in an open-circumferential configuration. Comparing aorta segments from nicotine-treated mice relative to an equal number of control counterparts, stiffness in the circumferential direction was nearly two-fold higher (377 kPa ± 165 kPa vs. 191 kPa ± 65 kPa, n = 5, p = 0.03) at 50% strain. Using a degradative power-law fit to fatigue data at supraphysiological loading, we observed that nicotine-treated aortas exhibited significantly higher peak stress, greater loss of tension, and wider oscillation band than control aortas (p = 0.01 for all three variables). Compared to simple stress relaxation tests, fatigue cycling is shown to be more sensitive and versatile in discerning nicotine-induced changes in mechanical behavior over many cycles. Supraphysiological fatigue cycling thus may have broader potential to reveal subtle changes in vascular mechanics caused by other exogenous toxins or pathological conditions.

    View details for DOI 10.1115/1.4051706

    View details for PubMedID 34244728

  • Publisher Correction: A multi-ethnic epigenome-wide association study of leukocyte DNA methylation and blood lipids. Nature communications Jhun, M., Mendelson, M., Wilson, R., Gondalia, R., Joehanes, R., Salfati, E., Zhao, X., Braun, K. V., Do, A. N., Hedman, A. K., Zhang, T., Carnero-Montoro, E., Shen, J., Bartz, T. M., Brody, J. A., Montasser, M. E., O'Connell, J. R., Yao, C., Xia, R., Boerwinkle, E., Grove, M., Guan, W., Liliane, P., Singmann, P., Muller-Nurasyid, M., Meitinger, T., Gieger, C., Peters, A., Zhao, W., Ware, E. B., Smith, J. A., Dhana, K., van Meurs, J., Uitterlinden, A., Ikram, M. A., Ghanbari, M., Zhi, D., Gustafsson, S., Lind, L., Li, S., Sun, D., Spector, T. D., Chen, Y. I., Damcott, C., Shuldiner, A. R., Absher, D. M., Horvath, S., Tsao, P. S., Kardia, S., Psaty, B. M., Sotoodehnia, N., Bell, J. T., Ingelsson, E., Chen, W., Dehghan, A., Arnett, D. K., Waldenberger, M., Hou, L., Whitsel, E. A., Baccarelli, A., Levy, D., Fornage, M., Irvin, M. R., Assimes, T. L. 2021; 12 (1): 4256

    View details for DOI 10.1038/s41467-021-24600-z

    View details for PubMedID 34230475

  • Genetic Evidence for Repurposing of GLP1R (Glucagon-Like Peptide-1 Receptor) Agonists to Prevent Heart Failure. Journal of the American Heart Association Daghlas, I., Karhunen, V., Ray, D., Zuber, V., Burgess, S., Tsao, P. S., Lynch, J. A., Lee, K. M., Voight, B. F., Chang, K., Baker, E. H., Damrauer, S. M., Howson, J. M., Vujkovic, M., Gill, D. 2021: e020331

    Abstract

    Background This study was designed to investigate the genetic evidence for repurposing of GLP1R (glucagon-like peptide-1 receptor) agonists to prevent heart failure (HF) and whether the potential benefit exceeds the benefit conferred by more general glycemic control. Methods and Results We applied 2-sample Mendelian randomization of genetically proxied GLP1R agonism on HF as the main outcome and left ventricular ejection fraction as the secondary outcome. The associations were compared with those of general glycemic control on the same outcomes. Genetic associations were obtained from genome-wide association study summary statistics of type 2 diabetes mellitus (228499 cases and 1178783 controls), glycated hemoglobin (n=344182), HF (47,309 cases and 930014 controls), and left ventricular ejection fraction (n=16923). Genetic proxies for GLP1R agonism associated with reduced risk of HF (odds ratio per 1mmol/mol decrease in glycated hemoglobin 0.75; 95% CI, 0.64-0.87; P=1.69*10-4), and higher left ventricular ejection fraction (SD change in left ventricular ejection fraction per 1mmol/mol decrease in glycated hemoglobin 0.22%; 95% CI, 0.03-0.42; P=0.03). The magnitude of these benefits exceeded those expected from improved glycemic control more generally. The results were similar in sensitivity analyses, and we did not find evidence to suggest that these associations were mediated by reduced coronary artery disease risk. Conclusions This genetic evidence supports the repurposing of GLP1R agonists for preventing HF.

    View details for DOI 10.1161/JAHA.120.020331

    View details for PubMedID 34184541

  • A multi-ethnic epigenome-wide association study of leukocyte DNA methylation and blood lipids. Nature communications Jhun, M., Mendelson, M., Wilson, R., Gondalia, R., Joehanes, R., Salfati, E., Zhao, X., Braun, K. V., Do, A. N., Hedman, A. K., Zhang, T., Carnero-Montoro, E., Shen, J., Bartz, T. M., Brody, J. A., Montasser, M. E., O'Connell, J. R., Yao, C., Xia, R., Boerwinkle, E., Grove, M., Guan, W., Liliane, P., Singmann, P., Muller-Nurasyid, M., Meitinger, T., Gieger, C., Peters, A., Zhao, W., Ware, E. B., Smith, J. A., Dhana, K., van Meurs, J., Uitterlinden, A., Ikram, M. A., Ghanbari, M., Zhi, D., Gustafsson, S., Lind, L., Li, S., Sun, D., Spector, T. D., Chen, Y. I., Damcott, C., Shuldiner, A. R., Absher, D. M., Horvath, S., Tsao, P. S., Kardia, S., Psaty, B. M., Sotoodehnia, N., Bell, J. T., Ingelsson, E., Chen, W., Dehghan, A., Arnett, D. K., Waldenberger, M., Hou, L., Whitsel, E. A., Baccarelli, A., Levy, D., Fornage, M., Irvin, M. R., Assimes, T. L. 2021; 12 (1): 3987

    Abstract

    Here we examine the association between DNA methylation in circulating leukocytes and blood lipids in a multi-ethnic sample of 16,265 subjects. We identify 148, 35, and 4 novel associations among Europeans, African Americans, and Hispanics, respectively, and an additional 186 novel associations through a trans-ethnic meta-analysis. We observe a high concordance in the direction of effects across racial/ethnic groups, a high correlation of effect sizes between high-density lipoprotein and triglycerides, a modest overlap of associations with epigenome-wide association studies of other cardio-metabolic traits, and a largely non-overlap with lipid loci identified to date through genome-wide association studies. Thirty CpGs reached significance in at least 2 racial/ethnic groups including 7 that showed association with the expression of an annotated gene. CpGs annotated to CPT1A showed evidence of being influenced by triglycerides levels. DNA methylation levels of circulating leukocytes show robust and consistent association with blood lipid levels across multiple racial/ethnic groups.

    View details for DOI 10.1038/s41467-021-23899-y

    View details for PubMedID 34183656

  • Prioritizing the Role of Major Lipoproteins and Subfractions as Risk Factors for Peripheral Artery Disease. Circulation Levin, M. G., Zuber, V., Walker, V. M., Klarin, D., Lynch, J., Malik, R., Aday, A. W., Bottolo, L., Pradhan, A. D., Dichgans, M., Chang, K., Rader, D. J., Tsao, P. S., Voight, B. F., Gill, D., Burgess, S., Damrauer, S. M., VA Million Veteran Program 2021

    Abstract

    Background: Lipoprotein-related traits have been consistently identified as risk factors for atherosclerotic cardiovascular disease, largely on the basis of studies of coronary artery disease (CAD). The relative contributions of specific lipoproteins to risk of peripheral artery disease (PAD) have not been well-defined. We leveraged large-scale genetic association data to investigate effects of circulating lipoprotein-related traits on PAD risk. Methods: Genome-wide association study summary statistics for circulating lipoprotein-related traits were used in the MR Bayesian model averaging framework to prioritize the most likely causal major lipoprotein and subfraction risk factors for PAD and CAD. MR was used to estimate the effect of ApoB-lowering on PAD risk using gene regions proxying lipid-lowering drug targets. Genes relevant to prioritized lipoprotein subfractions were identified using transcriptome-wide association studies. Results: ApoB was identified as the most likely causal lipoprotein-related risk factor for both PAD (marginal inclusion probability [MIP] 0.86, p = 0.003) and CAD (MIP 0.92, p = 0.005). Genetic proxies for ApoB (apolipoprotein B)-lowering medications were associated with reduced risk of both PAD (OR 0.87 per 1 standard deviation decrease in ApoB, 95% CI 0.84 to 0.91, p = 9 x 10-10) and CAD (OR 0.66, 95% CI 0.63 to 0.69, p = 4 x 10-73), with a stronger predicted effect of ApoB-lowering on CAD (ratio of effects 3.09, 95% CI 2.29 to 4.60, p < 1 * 10-6). Extra-small-VLDL particle concentration (XS.VLDL.P) was identified as the most likely subfraction associated with PAD risk (MIP 0.91, p = 2.3 x 10-4), while large-LDL particle concentration (L.LDL.P) was the most likely subfraction associated with CAD risk (MIP 0.95, p = 0.011). Genes associated with XS.VLDL.P and L.LDL.P included canonical ApoB-pathway components, although gene-specific effects were variable. Lipoprotein(a) was associated with increased risk of PAD, independent of ApoB (OR 1.04, 95% CI 1.03 to 1.04, 95% CI 1.0 x 10-33). Conclusions: ApoB was prioritized as the major lipoprotein fraction causally responsible for both PAD and CAD risk. However, ApoB-lowering drug targets and ApoB-containing lipoprotein subfractions had diverse associations with ASCVD, and distinct subfraction-associated genes suggest possible differences in the role of lipoproteins in the pathogenesis of PAD and CAD.

    View details for DOI 10.1161/CIRCULATIONAHA.121.053797

    View details for PubMedID 34139859

  • Genetic Determinants of Peripheral Artery Disease. Circulation research Klarin, D., Tsao, P. S., Damrauer, S. M. 2021; 128 (12): 1805-1817

    Abstract

    Peripheral artery disease-atherosclerosis of the abdominal aorta and lower extremity vascular bed-is a complex disease with both environmental and genetic determinants. Unmitigated disease is associated with major functional decline and can lead to chronic limb-threatening ischemia, amputation, and increased mortality. Over the last 10 years, major advances have been made in identifying the genetic basis of this common, complex disease. In this review, we provide an overview of the primary types of genetic analyses performed for peripheral artery disease, including heritability and linkage studies, and more recently biobank-based genome-wide association studies. Looking forward, we highlight areas of future study including efforts to identify causal peripheral artery disease genes, rare variant and structural variant analyses using whole-exome and whole-genome sequencing data, and the need to include individuals of diverse genetic ancestries.

    View details for DOI 10.1161/CIRCRESAHA.121.318327

    View details for PubMedID 34110906

  • MicroRNA miR-29b regulates diabetic aortic remodeling and stiffening. Molecular therapy. Nucleic acids Schellinger, I. N., Wagenhauser, M., Chodisetti, G., Mattern, K., Dannert, A., Petzold, A., Jakubizka-Smorag, J., Emrich, F., Haunschild, J., Schuster, A., Schwob, E., Schulz, K., Maegdefessel, L., Spin, J. M., Stumvoll, M., HasenfuSS, G., Tsao, P. S., Raaz, U. 2021; 24: 188–99

    Abstract

    Patients with type 2 diabetes (T2D) are threatened by excessive cardiovascular morbidity and mortality. While accelerated arterial stiffening may represent a critical mechanistic factor driving cardiovascular risk in T2D, specific therapies to contain the underlying diabetic arterial remodeling have been elusive. The present translational study investigates the role of microRNA-29b (miR-29b) as a driver and therapeutic target of diabetic aortic remodeling and stiffening. Using a murine model (db/db mice), as well as human aortic tissue samples, we find that diabetic aortic remodeling and stiffening is associated with medial fibrosis, as well as fragmentation of aortic elastic layers. miR-29b is significantly downregulated in T2D and miR-29b repression is sufficient to induce both aortic medial fibrosis and elastin breakdown through upregulation of its direct target genes COL1A1 and MMP2 thereby increasing aortic stiffness. Moreover, antioxidant treatment restores aortic miR-29b levels and counteracts diabetic aortic remodeling. Concluding, we identify miR-29b as a comprehensive-and therefore powerful-regulator of aortic remodeling and stiffening in T2D that moreover qualifies as a (redox-sensitive) target for therapeutic intervention.

    View details for DOI 10.1016/j.omtn.2021.02.021

    View details for PubMedID 33767915

  • Association of the transthyretin variant V122I with polyneuropathy among individuals of African ancestry. Scientific reports Parker, M. M., Damrauer, S. M., Tcheandjieu, C., Erbe, D., Aldinc, E., Hawkins, P. N., Gillmore, J. D., Hull, L. E., Lynch, J. A., Joseph, J., Ticau, S., Flynn-Carroll, A. O., Deaton, A. M., Ward, L. D., Assimes, T. L., Tsao, P. S., Chang, K., Rader, D. J., Fitzgerald, K., Vaishnaw, A. K., Hinkle, G., Nioi, P. 2021; 11 (1): 11645

    Abstract

    Hereditary transthyretin-mediated (hATTR) amyloidosis is an underdiagnosed, progressively debilitating disease caused by mutations in the transthyretin (TTR) gene. V122I, a common pathogenic TTR mutation, is found in 3-4% of individuals of African ancestry in the United States and has been associated with cardiomyopathy and heart failure. To better understand the phenotypic consequences of carrying V122I, we conducted a phenome-wide association study scanning 427 ICD diagnosis codes in UK Biobank participants of African ancestry (n=6062). Significant associations were tested for replication in the Penn Medicine Biobank (n=5737) and the Million Veteran Program (n=82,382). V122I was significantly associated with polyneuropathy in the UK Biobank (odds ratio [OR]=6.4, 95% confidence interval [CI] 2.6-15.6, p=4.2*10-5), which was replicated in the Penn Medicine Biobank (OR=1.6, 95% CI 1.2-2.4, p=6.0*10-3) and Million Veteran Program (OR=1.5, 95% CI 1.2-1.8, p=1.8*10-4). Polyneuropathy prevalence among V122I carriers was 2.1%, 9.0%, and 4.8% in the UK Biobank, Penn Medicine Biobank, and Million Veteran Program, respectively. The cumulative incidence of common hATTR amyloidosis manifestations (carpal tunnel syndrome, polyneuropathy, cardiomyopathy, heart failure) was significantly enriched in V122I carriers compared with non-carriers (HR=2.8, 95% CI 1.7-4.5, p=2.6*10-5) in the UK Biobank, with 37.4% of V122I carriers having at least one of these manifestations by age 75. Our findings show that V122I carriers are at increased risk of polyneuropathy. These results also emphasize the underdiagnosis of disease in V122I carriers with a significant proportion of subjects showing phenotypic changes consistent with hATTR amyloidosis. Greater understanding of the manifestations associated with V122I is critical for earlier diagnosis and treatment.

    View details for DOI 10.1038/s41598-021-91113-6

    View details for PubMedID 34079032

  • Risk factors mediating the effect of body mass index and waist-to-hip ratio on cardiovascular outcomes: Mendelian randomization analysis. International journal of obesity (2005) Gill, D., Zuber, V., Dawson, J., Pearson-Stuttard, J., Carter, A. R., Sanderson, E., Karhunen, V., Levin, M. G., Wootton, R. E., Klarin, D., Tsao, P. S., Tsilidis, K. K., Damrauer, S. M., Burgess, S., Elliott, P. 2021

    Abstract

    BACKGROUND: Higher body mass index (BMI) and waist-to-hip ratio (WHR) increase the risk of cardiovascular disease, but the extent to which this is mediated by blood pressure, diabetes, lipid traits, and smoking is not fully understood.METHODS: Using consortia and UK Biobank genetic association summary data from 140,595 to 898,130 participants predominantly of European ancestry, Mendelian randomization mediation analysis was performed to investigate the degree to which systolic blood pressure (SBP), diabetes, lipid traits, and smoking mediated an effect of BMI and WHR on the risk of coronary artery disease (CAD), peripheral artery disease (PAD) and stroke.RESULTS: The odds ratio of CAD per 1-standard deviation increase in genetically predicted BMI was 1.49 (95% CI 1.39 to 1.60). This attenuated to 1.34 (95% CI 1.24 to 1.45) after adjusting for genetically predicted SBP (proportion mediated 27%, 95% CI 3% to 50%), to 1.27 (95% CI 1.17 to 1.37) after adjusting for genetically predicted diabetes (41% mediated, 95% CI 18% to 63%), to 1.47 (95% CI 1.36 to 1.59) after adjusting for genetically predicted lipids (3% mediated, 95% -23% to 29%), and to 1.46 (95% CI 1.34 to 1.58) after adjusting for genetically predicted smoking (6% mediated, 95% CI -20% to 32%). Adjusting for all the mediators together, the estimate attenuated to 1.14 (95% CI 1.04 to 1.26; 66% mediated, 95% CI 42% to 91%). A similar pattern was observed when considering genetically predicted WHR as the exposure, and PAD or stroke as the outcome.CONCLUSIONS: Measures to reduce obesity will lower the risk of cardiovascular disease primarily by impacting downstream metabolic risk factors, particularly diabetes and hypertension. Reduction of obesity prevalence alongside control and management of its mediators is likely to be most effective for minimizing the burden of obesity.

    View details for DOI 10.1038/s41366-021-00807-4

    View details for PubMedID 34002035

  • Genetic analysis in European ancestry individuals identifies 517 loci associated with liver enzymes. Nature communications Pazoki, R., Vujkovic, M., Elliott, J., Evangelou, E., Gill, D., Ghanbari, M., van der Most, P. J., Pinto, R. C., Wielscher, M., Farlik, M., Zuber, V., de Knegt, R. J., Snieder, H., Uitterlinden, A. G., Lifelines Cohort Study, Lynch, J. A., Jiang, X., Said, S., Kaplan, D. E., Lee, K. M., Serper, M., Carr, R. M., Tsao, P. S., Atkinson, S. R., Dehghan, A., Tzoulaki, I., Ikram, M. A., Herzig, K., Jarvelin, M., Alizadeh, B. Z., O'Donnell, C. J., Saleheen, D., Voight, B. F., Chang, K., Thursz, M. R., Elliott, P., VA Million Veteran Program, Boezen, H. M., Franke, L., van der Harst, P., Navis, G., Rots, M., Swertz, M., Wolffenbuttel, B. H., Wijmenga, C., Ballas, Z. K., Bhushan, S., Boyko, E. J., Cohen, D. M., Concato, J., Aslan, M., Zhao, H., Constans, J. I., Dellitalia, L. J., Fayad, J. M., Fernando, R. S., Florez, H. J., Gaddy, M. A., Gappy, S. S., Gibson, G., Godschalk, M., Greco, J. A., Gupta, S., Gutierrez, S., Hammer, K. D., Hamner, M. B., Harley, J. B., Hung, A. M., Huq, M., Hurley, R. A., Iruvanti, P. R., Ivins, D. J., Jacono, F. J., Jhala, D. N., Kaminsky, L. S., Klein, J. B., Liangpunsakul, S., Lichy, J. H., Moser, J., Huang, G. D., Muralidhar, S., Mastorides, S. M., Mathew, R. O., Mattocks, K. M., McArdle, R., Meyer, P. N., Meyer, L. J., Moorman, J. P., Morgan, T. R., Murdoch, M., Okusaga, O. O., Oursler, K. K., Ratcliffe, N. R., Rauchman, M. I., Robey, R. B., Ross, G. W., Servatius, R. J., Sharma, S. C., Sherman, S. E., Sonel, E., Sriram, P., Stapley, T., Striker, R. T., Tandon, N., Villareal, G., Wallbom, A. S., Wells, J. M., Whittle, J. C., Whooley, M. A., Wilson, P. W., Sun, Y. V., Xu, J., Yeh, S., Connor, T., Argyres, D. P., Hauser, E. R., Beckham, J. C., Stephens, B., Aguayo, S. M., Ahuja, S. K., Pyarajan, S., Cho, K., Gaziano, J. M., Kinlay, S., Nguyen, X. T., Brewer, J. V., Brophy, M. T., Do, N. V., Humphries, D. E., Selva, L. E., Shayan, S., Whitbourne, S. B., Breeling, J. L., Romero, J. P., Ramoni, R. B. 2021; 12 (1): 2579

    Abstract

    Serum concentration of hepatic enzymes are linked to liver dysfunction, metabolic and cardiovascular diseases. We perform genetic analysis on serum levels of alanine transaminase (ALT), alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT) using data on 437,438 UK Biobank participants. Replication in 315,572 individuals from European descent from the Million Veteran Program, Rotterdam Study and Lifeline study confirms 517 liver enzyme SNPs. Genetic risk score analysis using the identified SNPs is strongly associated with serum activity of liver enzymes in two independent European descent studies (The Airwave Health Monitoring study and the Northern Finland Birth Cohort 1966). Gene-set enrichment analysis using the identified SNPs highlights involvement in liver development and function, lipid metabolism, insulin resistance, and vascular formation. Mendelian randomization analysis shows association of liver enzyme variants with coronary heart disease and ischemic stroke. Genetic risk score for elevated serum activity of liver enzymes is associated with higher fat percentage of body, trunk, and liver and body mass index. Our study highlights the role of molecular pathways regulated by the liver in metabolic disorders and cardiovascular disease.

    View details for DOI 10.1038/s41467-021-22338-2

    View details for PubMedID 33972514

  • Response by Pan and Tsao to Letter Regarding Article, "Genetic Architecture of Abdominal Aortic Aneurysm in the Million Veteran Program". Circulation Pan, C., Tsao, P. S. 2021; 143 (17): e873–e874

    View details for DOI 10.1161/CIRCULATIONAHA.121.053669

    View details for PubMedID 33900828

  • Association Between Genetic Variation in Blood Pressure and Increased Lifetime Risk of Peripheral Artery Disease. Arteriosclerosis, thrombosis, and vascular biology Levin, M. G., Klarin, D., Walker, V. M., Gill, D., Lynch, J., Hellwege, J. N., Keaton, J. M., Lee, K. M., Assimes, T. L., Natarajan, P., Hung, A. M., Edwards, T., Rader, D. J., Gaziano, J. M., Davies, N. M., Tsao, P. S., Chang, K., Voight, B. F., Damrauer, S. M. 2021: ATVBAHA120315482

    Abstract

    OBJECTIVE: We aimed to estimate the effect of blood pressure (BP) traits and BP-lowering medications (via genetic proxies) on peripheral artery disease. Approach and Results: Genome-wide association studies summary statistics were obtained for BP, peripheral artery disease (PAD), and coronary artery disease. Causal effects of BP on PAD were estimated by 2-sample Mendelian randomization using a range of pleiotropy-robust methods. Increased systolic BP (SBP), diastolic BP, mean arterial pressure (MAP), and pulse pressure each significantly increased risk of PAD (SBP odds ratio [OR], 1.20 [1.16-1.25] per 10 mmHg increase, P=1*10-24; diastolic BP OR, 1.27 [1.18-1.35], P=4*10-11; MAP OR, 1.26 [1.19-1.33], P=6*10-16; pulse pressure OR, 1.31 [1.24-1.39], P=9*10-23). The effects of SBP, diastolic BP, and MAP were greater for coronary artery disease than PAD (SBP ratio of Ors, 1.06 [1.0-1.12], P=0.04; MAP ratio of OR, 1.15 [1.06-1.26], P=8.6*10-4; diastolic BP ratio of OR, 1.21 [1.08-1.35], P=6.9*10-4). Considered jointly, both pulse pressure and MAP directly increased risk of PAD (pulse pressure OR, 1.26 [1.17-1.35], P=3*10-10; MAP OR, 1.14 [1.06-1.23], P=2*10-4). The effects of antihypertensive medications were estimated using genetic instruments. SBP-lowering via beta-blocker (OR, 0.74 per 10 mmHg decrease in SBP [95% CI, 0.65-0.84]; P=5*10-6), loop diuretic (OR, 0.66 [0.48-0.91], P=0.01), and thiazide diuretic (OR, 0.57 [0.41-0.79], P=6*10-4) associated variants were protective of PAD.CONCLUSIONS: Higher BP is likely to cause PAD. BP-lowering through beta blockers, loop diuretics, and thiazide diuretics (as proxied by genetic variants) was associated with decreased risk of PAD. Future study is needed to clarify the specific mechanisms by which BP influences PAD.

    View details for DOI 10.1161/ATVBAHA.120.315482

    View details for PubMedID 33853351

  • Actionable druggable genome-wide Mendelian randomization identifies repurposing opportunities for COVID-19. Nature medicine Gaziano, L., Giambartolomei, C., Pereira, A. C., Gaulton, A., Posner, D. C., Swanson, S. A., Ho, Y., Iyengar, S. K., Kosik, N. M., Vujkovic, M., Gagnon, D. R., Bento, A. P., Barrio-Hernandez, I., Ronnblom, L., Hagberg, N., Lundtoft, C., Langenberg, C., Pietzner, M., Valentine, D., Gustincich, S., Tartaglia, G. G., Allara, E., Surendran, P., Burgess, S., Zhao, J. H., Peters, J. E., Prins, B. P., Angelantonio, E. D., Devineni, P., Shi, Y., Lynch, K. E., DuVall, S. L., Garcon, H., Thomann, L. O., Zhou, J. J., Gorman, B. R., Huffman, J. E., O'Donnell, C. J., Tsao, P. S., Beckham, J. C., Pyarajan, S., Muralidhar, S., Huang, G. D., Ramoni, R., Beltrao, P., Danesh, J., Hung, A. M., Chang, K., Sun, Y. V., Joseph, J., Leach, A. R., Edwards, T. L., Cho, K., Gaziano, J. M., Butterworth, A. S., Casas, J. P., VA Million Veteran Program COVID-19 Science Initiative 2021

    Abstract

    Drug repurposing provides a rapid approach to meet the urgent need for therapeutics to address COVID-19. To identify therapeutic targets relevant to COVID-19, we conducted Mendelian randomization analyses, deriving genetic instruments based on transcriptomic and proteomic data for 1,263 actionable proteins that are targeted by approved drugs or in clinical phase of drug development. Using summary statistics from the Host Genetics Initiative and the Million Veteran Program, we studied 7,554 patients hospitalized with COVID-19 and >1 million controls. We found significant Mendelian randomization results for three proteins (ACE2, P=1.6*10-6; IFNAR2, P=9.8*10-11 and IL-10RB, P=2.3*10-14) using cis-expression quantitative trait loci genetic instruments that also had strong evidence for colocalization with COVID-19 hospitalization. To disentangle the shared expression quantitative trait loci signal for IL10RB and IFNAR2, we conducted phenome-wide association scans and pathway enrichment analysis, which suggested that IFNAR2 is more likely to play a role in COVID-19 hospitalization. Our findings prioritize trials of drugs targeting IFNAR2 and ACE2 for early management of COVID-19.

    View details for DOI 10.1038/s41591-021-01310-z

    View details for PubMedID 33837377

  • Discovery of rare variants associated with blood pressure regulation through meta-analysis of 1.3 million individuals (vol 52, pg 1314, 2020) NATURE GENETICS Surendran, P., Feofanova, E. V., Lahrouchi, N., Ntalla, I., Karthikeyan, S., Cook, J., Chen, L., Mifsud, B., Yao, C., Kraja, A. T., Cartwright, J. H., Hellwege, J. N., Giri, A., Tragante, V., Thorleifsson, G., Liu, D. J., Prins, B. P., Stewart, I. D., Cabrera, C. P., Eales, J. M., Akbarov, A., Auer, P. L., Bielak, L. F., Bis, J. C., Braithwaite, V. S., Brody, J. A., Daw, E., Warren, H. R., Drenos, F., Nielsen, S., Faul, J. D., Fauman, E. B., Fava, C., Ferreira, T., Foley, C. N., Franceschini, N., Gao, H., Giannakopoulou, O., Giulianini, F., Gudbjartsson, D. F., Guo, X., Harris, S. E., Havulinna, A. S., Helgadottir, A., Huffman, J. E., Hwang, S., Kanoni, S., Kontto, J., Larson, M. G., Li-Gao, R., Lindstrom, J., Lotta, L. A., Lu, Y., Luan, J., Mahajan, A., Malerba, G., Masca, N. D., Mei, H., Menni, C., Mook-Kanamori, D. O., Mosen-Ansorena, D., Muller-Nurasyid, M., Pare, G., Paul, D. S., Perola, M., Poveda, A., Rauramaa, R., Richard, M., Richardson, T. G., Sepulveda, N., Sim, X., Smith, A. V., Smith, J. A., Staley, J. R., Stanakova, A., Sulem, P., Theriault, S., Thorsteinsdottir, U., Trompet, S., Varga, T. V., Velez Edwards, D. R., Veronesi, G., Weiss, S., Willems, S. M., Yao, J., Young, R., Yu, B., Zhang, W., Zhao, J., Zhao, W., Zhao, W., Evangelou, E., Aeschbacher, S., Asllanaj, E., Blankenberg, S., Bonnycastle, L. L., Bork-Jensen, J., Brandslund, I., Braund, P. S., Burgess, S., Cho, K., Christensen, C., Connell, J., de Mutsert, R., Dominiczak, A. F., Dorr, M., Eiriksdottir, G., Farmaki, A., Gaziano, J., Grarup, N., Grove, M. L., Hallmans, G., Hansen, T., Have, C. T., Heiss, G., Jorgensen, M. E., Jousilahti, P., Kajantie, E., Kamat, M., Karajamaki, A., Karpe, F., Koistinen, H. A., Kovesdy, C. P., Kuulasmaa, K., Laatikainen, Lannfelt, L., Lee, I., Lee, W., Linneberg, A., Martin, L. W., Moitry, M., Nadkarni, G., Neville, M. J., Palmer, C. A., Papanicolaou, G. J., Pedersen, O., Peters, J., Poulter, N., Rasheed, A., Rasmussen, K. L., Rayner, N., Magi, R., Renstrom, F., Rettig, R., Rossouw, J., Schreiner, P. J., Sever, P. S., Sigurdsson, E. L., Skaaby, T., Sun, Y. V., Sundstrom, J., Thorgeirsson, G., Esko, T., Trabetti, E., Tsao, P. S., Tuomi, T., Turner, S. T., Tzoulaki, I., Vaartjes, I., Vergnaud, A., Willer, C. J., Wilson, P. F., Witte, D. R., Yonova-Doing, E., Zhang, H., Aliya, N., Almgren, P., Amouyel, P., Asselbergs, F. W., Barnes, M. R., Blakemore, A. I., Boehnke, M., Bots, M. L., Bottinger, E. P., Buring, J. E., Chambers, J. C., Chen, Y., Chowdhury, R., Conen, D., Correa, A., Davey Smith, G., Boer, R., Deary, I. J., Dedoussis, G., Deloukas, P., Di Angelantonio, E., Elliott, P., Felix, S. B., Ferrieres, J., Ford, I., Fornage, M., Franks, P. W., Franks, S., Frossard, P., Gambaro, G., Gaunt, T. R., Groop, L., Gudnason, V., Harris, T. B., Hayward, C., Hennig, B. J., Herzig, K., Ingelsson, E., Tuomilehto, J., Jarvelin, M., Jukema, J., Kardia, S. R., Kee, F., Kooner, J. S., Kooperberg, C., Launer, L. J., Lind, L., Loos, R. F., Majumder, A., Laakso, M., McCarthy, M. I., Melander, O., Mohlke, K. L., Murray, A. D., Nordestgaard, B., Orho-Melander, M., Packard, C. J., Padmanabhan, S., Palmas, W., Polasek, O., Porteous, D. J., Prentice, A. M., Province, M. A., Relton, C. L., Rice, K., Ridker, P. M., Rolandsson, O., Rosendaal, F. R., Rotter, J. I., Rudan, I., Salomaa, V., Samani, N. J., Sattar, N., Sheu, W., Smith, B. H., Soranzo, N., Spector, T. D., Starr, J. M., Sebert, S., Taylor, K. D., Lakka, T. A., Timpson, N. J., Tobin, M. D., van der Harst, P., van der Meer, P., Ramachandran, V. S., Verweij, N., Virtamo, J., Volker, U., Weir, D. R., Zeggini, E., Charchar, F. J., Wareham, N. J., Langenberg, C., Tomaszewski, M., Butterworth, A. S., Caulfield, M. J., Danesh, J., Edwards, T. L., Holm, H., Hung, A. M., Lindgren, C. M., Liu, C., Manning, A. K., Morris, A. P., Morrison, A. C., O'Donnell, C. J., Psaty, B. M., Saleheen, D., Stefansson, K., Boerwinkle, E., Chasman, D. I., Levy, D., Newton-Cheh, C., Munroe, P. B., Howson, J. M., LifeLines Cohort Study, EPIC CVD, EPIC InterAct, Understanding Soc Sci Grp, Million Veteran Program 2021

    View details for DOI 10.1038/s41588-021-00832-z

    View details for Web of Science ID 000629572200001

    View details for PubMedID 33727701

  • Hummingbird: Efficient Performance Prediction for Executing Genomic Applications in the Cloud. Bioinformatics (Oxford, England) Bahmani, A., Xing, Z., Krishnan, V., Ray, U., Mueller, F., Alavi, A., Tsao, P. S., Snyder, M. P., Pan, C. 2021

    Abstract

    MOTIVATION: A major drawback of executing genomic applications on cloud computing facilities is the lack of tools to predict which instance type is the most appropriate, often resulting in an over- or under- matching of resources. Determining the right configuration before actually running the applications will save money and time. Here, we introduce Hummingbird, a tool for predicting performance of computing instances with varying memory and CPU on multiple cloud platforms.RESULTS: Our experiments on three major genomic data pipelines, including GATK HaplotypeCaller, GATK MuTect2, and ENCODE ATAC-seq, showed that Hummingbird was able to address applications in command line specified in JSON format or workflow description language (WDL) format, and accurately predicted the fastest, the cheapest, and the most cost-efficient compute instances in an economic manner.AVAILABILITY: Hummingbird is available as an open source tool at: https://github.com/StanfordBioinformatics/Hummingbird.SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

    View details for DOI 10.1093/bioinformatics/btab161

    View details for PubMedID 33693476

  • Exosome miR-501-3p Elevation Contributes to Progression of Vascular Stiffness. Circulation reports Toyama, K., Igase, M., Spin, J. M., Abe, Y., Javkhlant, A., Okada, Y., Wagenhauser, M. U., Schelzig, H., Tsao, P. S., Mogi, M. 2021; 3 (3): 170–77

    Abstract

    Background: Tight junction (TJ) disruption and dysfunction are involved in the progression of arteriosclerosis. miR-501-3p regulates endothelial TJ protein-1, resulting in TJ disruption. Because exosomal microRNAs can travel to distant tissues and influence cell behavior, patients with elevated miR-501-3p may experience accelerated vascular disease progression secondary to miR-501-3p-induced reductions in TJ. This study investigated whether plasma exosome miR-501-3p levels are associated with vascular stiffness, an indicator for arteriosclerotic changes. Methods and Results: Fifty-one subjects (mean [±SD] age 70±8 years, 37% male) enrolled in a medical checkup program were recruited to the study. Brachial-ankle arterial pulse wave velocity (baPWV) and plasma exosome miR-501-3p expression were measured. Patients were divided into 2 groups depending on whether their miR-501-3p ∆Ct values were above ("High"; n=24) or below ("Low"; n=27) the cut-off levels determined by receiver operating characteristic (ROC) curve analysis. Median (interquartile range) baPWV levels were significantly higher in the miR-501-3p High than Low group (1,664 [1,496-1,859] vs. 1,450 [1,353-1,686] cm/s, respectively; P<0.05). Multivariate logistic regression analysis showed a significant association between increased baPWV and High miR-501-3p expression (odds ratio 4.66). At follow-up visits (mean 62 months later), baPWV remained significantly higher in the miR-501-3p High than Low group (1,830 [1,624-2,056] vs. 1,620 [1,377-1,816] cm/s, respectively; P<0.05). Conclusions: High expression levels of exosome miR-501-3p contribute to arteriosclerotic changes.

    View details for DOI 10.1253/circrep.CR-20-0135

    View details for PubMedID 33738350

  • Multi-trait association studies discover pleiotropic loci between Alzheimer's disease and cardiometabolic traits. Alzheimer's research & therapy Bone, W. P., Siewert, K. M., Jha, A., Klarin, D., Damrauer, S. M., VA Million Veteran Program, Chang, K., Tsao, P. S., Assimes, T. L., Ritchie, M. D., Voight, B. F., Ballas, Z. K., Bhushan, S., Boyko, E. J., Cohen, D. M., Concato, J., Constans, J. I., Dellitalia, L. J., Fayad, J. M., Fernando, R. S., Florez, H. J., Gaddy, M. A., Gappy, S. S., Gibson, G., Godschalk, M., Greco, J. A., Gupta, S., Gutierrez, S., Hammer, K. D., Hamner, M. B., Harley, J. B., Hung, A. M., Huq, M., Hurley, R. A., Iruvanti, P. R., Ivins, D. J., Jacono, F. J., Jhala, D. N., Kaminsky, L. S., Kinlay, S., Klein, J. B., Liangpunsakul, S., Lichy, J. H., Mastorides, S. M., Mathew, R. O., Mattocks, K. M., McArdle, R., Meyer, P. N., Meyer, L. J., Moorman, J. P., Morgan, T. R., Murdoch, M., Nguyen, X. T., Okusaga, O. O., Oursler, K. K., Ratcliffe, N. R., Rauchman, M. I., Robey, R. B., Ross, G. W., Servatius, R. J., Sharma, S. C., Sherman, S. E., Sonel, E., Sriram, P., Stapley, T., Striker, R. T., Tandon, N., Villareal, G., Wallbom, A. S., Wells, J. M., Whittle, J. C., Whooley, M. A., Xu, J., Yeh, S., Aslan, M., Brewer, J. V., Brophy, M. T., Connor, T., Argyres, D. P., Do, N. V., Hauser, E. R., Humphries, D. E., Selva, L. E., Shayan, S., Stephens, B., Whitbourne, S. B., Zhao, H., Moser, J., Beckham, J. C., Breeling, J. L., Romero, J. P., Huang, G. D., Ramoni, R. B., Muralidhar, S., Aguayo, S. M., Ahuja, S. K., Pyarajan, S., Sun, Y. V., Cho, K., Gaziano, J. M., Wilson, P. W., O'Donnell, C. J. 2021; 13 (1): 34

    Abstract

    BACKGROUND: Identification of genetic risk factors that are shared between Alzheimer's disease (AD) and other traits, i.e., pleiotropy, can help improve our understanding of the etiology of AD and potentially detect new therapeutic targets. Previous epidemiological correlations observed between cardiometabolic traits and AD led us to assess the pleiotropy between these traits.METHODS: We performed a set of bivariate genome-wide association studies coupled with colocalization analysis to identify loci that are shared between AD and eleven cardiometabolic traits. For each of these loci, we performed colocalization with Genotype-Tissue Expression (GTEx) project expression quantitative trait loci (eQTL) to identify candidate causal genes.RESULTS: We identified three previously unreported pleiotropic trait associations at known AD loci as well as four novel pleiotropic loci. One associated locus was tagged by a low-frequency coding variant in the gene DOCK4 and is potentially implicated in its alternative splicing. Colocalization with GTEx eQTL data identified additional candidate genes for the loci we detected, including ACE, the target of the hypertensive drug class of ACE inhibitors. We found that the allele associated with decreased ACE expression in brain tissue was also associated with increased risk of AD, providing human genetic evidence of a potential increase in AD risk from use of an established anti-hypertensive therapeutic.CONCLUSION: Our results support a complex genetic relationship between AD and these cardiometabolic traits, and the candidate causal genes identified suggest that blood pressure and immune response play a role in the pleiotropy between these traits.

    View details for DOI 10.1186/s13195-021-00773-z

    View details for PubMedID 33541420

  • Genetics of Smoking and Risk of Atherosclerotic Cardiovascular Diseases: A Mendelian Randomization Study. JAMA network open Levin, M. G., Klarin, D., Assimes, T. L., Freiberg, M. S., Ingelsson, E., Lynch, J., Natarajan, P., O'Donnell, C., Rader, D. J., Tsao, P. S., Chang, K., Voight, B. F., Damrauer, S. M., VA Million Veteran Program 2021; 4 (1): e2034461

    Abstract

    Importance: Smoking is associated with atherosclerotic cardiovascular disease, but the relative contribution to each subtype (coronary artery disease [CAD], peripheral artery disease [PAD], and large-artery stroke) remains less well understood.Objective: To determine the association between genetic liability to smoking and risk of CAD, PAD, and large-artery stroke.Design, Setting, and Participants: Mendelian randomization study using summary statistics from genome-wide associations of smoking (UK Biobank; up to 462 690 individuals), CAD (Coronary Artery Disease Genome Wide Replication and Meta-analysis plus the Coronary Artery Disease Genetics Consortium; up to 60 801 cases, 123 504 controls), PAD (VA Million Veteran Program; up to 24 009 cases, 150 983 controls), and large-artery stroke (MEGASTROKE; up to 4373 cases, 406 111 controls). This study was conducted using summary statistic data from large, previously described cohorts. Review of those publications does not reveal the total recruitment dates for those cohorts. Data analyses were conducted from August 2019 to June 2020.Exposures: Genetic liability to smoking (as proxied by genetic variants associated with lifetime smoking index).Main Outcomes and Measures: Risk (odds ratios [ORs]) of CAD, PAD, and large-artery stroke.Results: Genetic liability to smoking was associated with increased risk of PAD (OR, 2.13; 95% CI, 1.78-2.56; P=3.6*10-16), CAD (OR, 1.48; 95% CI, 1.25-1.75; P=4.4*10-6), and stroke (OR, 1.40; 95% CI, 1.02-1.92; P=.04). Genetic liability to smoking was associated with greater risk of PAD than risk of large-artery stroke (ratio of ORs, 1.52; 95% CI, 1.05-2.19; P=.02) or CAD (ratio of ORs, 1.44; 95% CI, 1.12-1.84; P=.004). The association between genetic liability to smoking and atherosclerotic cardiovascular diseases remained independent from the effects of smoking on traditional cardiovascular risk factors.Conclusions and Relevance: In this mendelian randomization analysis of data from large studies of atherosclerotic cardiovascular diseases, genetic liability to smoking was a strong risk factor for CAD, PAD, and stroke, although the estimated association was strongest between smoking and PAD. The association between smoking and atherosclerotic cardiovascular disease was independent of traditional cardiovascular risk factors.

    View details for DOI 10.1001/jamanetworkopen.2020.34461

    View details for PubMedID 33464320

  • Chitinase 3 like 1 (CHI3L1) is a regulator of smooth muscle cell physiology and atherosclerotic lesion stability. Cardiovascular research Tsantilas, P. n., Lao, S. n., Wu, Z. n., Eberhard, A. n., Winski, G. n., Vaerst, M. n., Nanda, V. n., Wang, Y. n., Kojima, Y. n., Ye, J. n., Flores, A. n., Jarr, K. U., Pelisek, J. n., Eckstein, H. H., Matic, L. n., Hedin, U. n., Tsao, P. S., Paloschi, V. n., Maegdefessel, L. n., Leeper, N. J. 2021

    Abstract

    Atherosclerotic cerebrovascular disease underlies the majority of ischemic strokes and is a major cause of death and disability. While plaque burden is a predictor of adverse outcomes, plaque vulnerability is increasingly recognized as a driver of lesion rupture and risk for clinical events. Defining the molecular regulators of carotid instability could inform the development of new biomarkers and/or translational targets for at-risk individuals.Using two independent human endarterectomy biobanks, we found that the understudied glycoprotein, Chitinase 3 like 1 (CHI3L1), is upregulated in patients with carotid disease compared to healthy controls. Further, CHI3L1 levels were found to stratify individuals based on symptomatology and histopathological evidence of an unstable fibrous cap. Gain- and loss-of-function studies in cultured human carotid artery smooth muscle cells (SMCs) showed that CHI3L1 prevents a number of maladaptive changes in that cell type, including phenotype switching towards a synthetic and hyperproliferative state. Using two murine models of carotid remodelling and lesion vulnerability, we found that knockdown of Chil1 resulted in larger neointimal lesions comprised by de-differentiated SMCs that failed to invest within and stabilize the fibrous cap. Exploratory mechanistic studies identified alterations in potential downstream regulatory genes, including large tumor suppressor kinase 2 (LATS2), which mediates macrophage marker and inflammatory cytokine expression on SMCs, and may explain how CHI3L1 modulates cellular plasticity.CHI3L1 is upregulated in humans with carotid artery disease and appears to be a strong mediator of plaque vulnerability. Mechanistic studies suggest this change may be a context-dependent adaptive response meant to maintain vascular SMCs in a differentiated state and to prevent rupture of the fibrous cap. Part of this effect may be mediated through downstream suppression of LATS2. Future studies should determine how these changes occur at the molecular level, and whether this gene can be targeted as a novel translational therapy for subjects at risk of stroke.Taken together, CHI3L1 has the potential to become a new translational target for cardiovascular disease. With further studies to understand its full causal relationship to inflammatory pathways, it could have a role in the diagnosis and management of patients with cerebrovascular disease at risk for stroke.

    View details for DOI 10.1093/cvr/cvab014

    View details for PubMedID 33471078

  • Multi-Trait Genome-Wide Association Study of Atherosclerosis Detects Novel Pleiotropic Loci. Frontiers in genetics Bellomo, T. R., Bone, W. P., Chen, B. Y., Gawronski, K. A., Zhang, D., Park, J., Levin, M., Tsao, N., Klarin, D., Lynch, J., Assimes, T. L., Gaziano, J. M., Wilson, P. W., Cho, K., Vujkovic, M., O'Donnell, C. J., Chang, K., Tsao, P. S., Rader, D. J., Ritchie, M. D., Damrauer, S. M., Voight, B. F. 2021; 12: 787545

    Abstract

    Although affecting different arterial territories, the related atherosclerotic vascular diseases coronary artery disease (CAD) and peripheral artery disease (PAD) share similar risk factors and have shared pathobiology. To identify novel pleiotropic loci associated with atherosclerosis, we performed a joint analysis of their shared genetic architecture, along with that of common risk factors. Using summary statistics from genome-wide association studies of nine known atherosclerotic (CAD, PAD) and atherosclerosis risk factors (body mass index, smoking initiation, type 2 diabetes, low density lipoprotein, high density lipoprotein, total cholesterol, and triglycerides), we perform 15 separate multi-trait genetic association scans which resulted in 25 novel pleiotropic loci not yet reported as genome-wide significant for their respective traits. Colocalization with single-tissue eQTLs identified candidate causal genes at 14 of the detected signals. Notably, the signal between PAD and LDL-C at the PCSK6 locus affects PCSK6 splicing in human liver tissue and induced pluripotent derived hepatocyte-like cells. These results show that joint analysis of related atherosclerotic disease traits and their risk factors allowed identification of unified biology that may offer the opportunity for therapeutic manipulation. The signal at PCSK6 represent possible shared causal biology where existing inhibitors may be able to be leveraged for novel therapies.

    View details for DOI 10.3389/fgene.2021.787545

    View details for PubMedID 35186008

  • A statistical quality assessment method for longitudinal observations in electronic health record data with an application to the VA million veteran program. BMC medical informatics and decision making Wang, H., Belitskaya-Levy, I., Wu, F., Lee, J. S., Shih, M. C., Tsao, P. S., Lu, Y. 2021; 21 (1): 289

    Abstract

    To describe an automated method for assessment of the plausibility of continuous variables collected in the electronic health record (EHR) data for real world evidence research use.The most widely used approach in quality assessment (QA) for continuous variables is to detect the implausible numbers using prespecified thresholds. In augmentation to the thresholding method, we developed a score-based method that leverages the longitudinal characteristics of EHR data for detection of the observations inconsistent with the history of a patient. The method was applied to the height and weight data in the EHR from the Million Veteran Program Data from the Veteran's Healthcare Administration (VHA). A validation study was also conducted.The receiver operating characteristic (ROC) metrics of the developed method outperforms the widely used thresholding method. It is also demonstrated that different quality assessment methods have a non-ignorable impact on the body mass index (BMI) classification calculated from height and weight data in the VHA's database.The score-based method enables automated and scaled detection of the problematic data points in health care big data while allowing the investigators to select the high-quality data based on their need. Leveraging the longitudinal characteristics in EHR will significantly improve the QA performance.

    View details for DOI 10.1186/s12911-021-01643-2

    View details for PubMedID 34670548

  • Swarm: A federated cloud framework for large-scale variant analysis. PLoS computational biology Bahmani, A. n., Ferriter, K. n., Krishnan, V. n., Alavi, A. n., Alavi, A. n., Tsao, P. S., Snyder, M. P., Pan, C. n. 2021; 17 (5): e1008977

    Abstract

    Genomic data analysis across multiple cloud platforms is an ongoing challenge, especially when large amounts of data are involved. Here, we present Swarm, a framework for federated computation that promotes minimal data motion and facilitates crosstalk between genomic datasets stored on various cloud platforms. We demonstrate its utility via common inquiries of genomic variants across BigQuery in the Google Cloud Platform (GCP), Athena in the Amazon Web Services (AWS), Apache Presto and MySQL. Compared to single-cloud platforms, the Swarm framework significantly reduced computational costs, run-time delays and risks of security breach and privacy violation.

    View details for DOI 10.1371/journal.pcbi.1008977

    View details for PubMedID 33979321

  • Phenome-wide association of 1809 phenotypes and COVID-19 disease progression in the Veterans Health Administration Million Veteran Program. PloS one Song, R. J., Ho, Y., Schubert, P., Park, Y., Posner, D., Lord, E. M., Costa, L., Gerlovin, H., Kurgansky, K. E., Anglin-Foote, T., DuVall, S., Huffman, J. E., Pyarajan, S., Beckham, J. C., Chang, K., Liao, K. P., Djousse, L., Gagnon, D. R., Whitbourne, S. B., Ramoni, R., Muralidhar, S., Tsao, P. S., O'Donnell, C. J., Gaziano, J. M., Casas, J. P., Cho, K., VA Million Veteran Program COVID-19 Science Initiative 2021; 16 (5): e0251651

    Abstract

    BACKGROUND: The risk factors associated with the stages of Coronavirus Disease-2019 (COVID-19) disease progression are not well known. We aim to identify risk factors specific to each state of COVID-19 progression from SARS-CoV-2 infection through death.METHODS AND RESULTS: We included 648,202 participants from the Veteran Affairs Million Veteran Program (2011-). We identified characteristics and 1,809 ICD code-based phenotypes from the electronic health record. We used logistic regression to examine the association of age, sex, body mass index (BMI), race, and prevalent phenotypes to the stages of COVID-19 disease progression: infection, hospitalization, intensive care unit (ICU) admission, and 30-day mortality (separate models for each). Models were adjusted for age, sex, race, ethnicity, number of visit months and ICD codes, state infection rate and controlled for multiple testing using false discovery rate (≤0.1). As of August 10, 2020, 5,929 individuals were SARS-CoV-2 positive and among those, 1,463 (25%) were hospitalized, 579 (10%) were in ICU, and 398 (7%) died. We observed a lower risk in women vs. men for ICU and mortality (Odds Ratio (95% CI): 0.48 (0.30-0.76) and 0.59 (0.31-1.15), respectively) and a higher risk in Black vs. Other race patients for hospitalization and ICU (OR (95%CI): 1.53 (1.32-1.77) and 1.63 (1.32-2.02), respectively). We observed an increased risk of all COVID-19 disease states with older age and BMI ≥35 vs. 20-24 kg/m2. Renal failure, respiratory failure, morbid obesity, acid-base balance disorder, white blood cell diseases, hydronephrosis and bacterial infections were associated with an increased risk of ICU admissions; sepsis, chronic skin ulcers, acid-base balance disorder and acidosis were associated with mortality.CONCLUSIONS: Older age, higher BMI, males and patients with a history of respiratory, kidney, bacterial or metabolic comorbidities experienced greater COVID-19 severity. Future studies to investigate the underlying mechanisms associated with these phenotype clusters and COVID-19 are warranted.

    View details for DOI 10.1371/journal.pone.0251651

    View details for PubMedID 33984066

  • E-Cigarettes and Cardiopulmonary Health. Function (Oxford, England) Tarran, R., Barr, R. G., Benowitz, N. L., Bhatnagar, A., Chu, H. W., Dalton, P., Doerschuk, C. M., Drummond, M. B., Gold, D. R., Goniewicz, M. L., Gross, E. R., Hansel, N. N., Hopke, P. K., Kloner, R. A., Mikheev, V. B., Neczypor, E. W., Pinkerton, K. E., Postow, L., Rahman, I., Samet, J. M., Salathe, M., Stoney, C. M., Tsao, P. S., Widome, R., Xia, T., Xiao, D., Wold, L. E. 2021; 2 (2): zqab004

    Abstract

    E-cigarettes have surged in popularity over the last few years, particularly among youth and young adults. These battery-powered devices aerosolize e-liquids, comprised of propylene glycol and vegetable glycerin, typically with nicotine, flavors, and stabilizers/humectants. Although the use of combustible cigarettes is associated with several adverse health effects including multiple pulmonary and cardiovascular diseases, the effects of e-cigarettes on both short- and long-term health have only begun to be investigated. Given the recent increase in the popularity of e-cigarettes, there is an urgent need for studies to address their potential adverse health effects, particularly as many researchers have suggested that e-cigarettes may pose less of a health risk than traditional combustible cigarettes and should be used as nicotine replacements. This report is prepared for clinicians, researchers, and other health care providers to provide the current state of knowledge on how e-cigarette use might affect cardiopulmonary health, along with research gaps to be addressed in future studies.

    View details for DOI 10.1093/function/zqab004

    View details for PubMedID 33748758

  • Unresolved Issues in RNA Therapeutics in Vascular Diseases With a Focus on Aneurysm Disease. Frontiers in cardiovascular medicine Schellinger, I. N., Dannert, A. R., Mattern, K., Raaz, U., Tsao, P. S. 2021; 8: 571076

    Abstract

    New technologies have greatly shaped the scientific and medical landscape within the last years. The unprecedented expansion of data and information on RNA biology has led to the discovery of new RNA classes with unique functions and unexpected modifications. Today, the biggest challenge is to transfer the large number of findings in basic RNA biology into corresponding clinical RNA-based therapeutics. Lately, this research begins to yield positive outcomes. RNA drugs advance to the final phases of clinical trials or even receive FDA approval. Furthermore, the introduction of the RNA-guided gene-editing technology CRISPR and advances in the delivery of messenger RNAs have triggered a major progression in the field of RNA-therapeutics. Especially short interfering RNAs and antisense oligonucleotides are promising examples for novel categories of therapeutics. However, several issues need to be addressed including intracellular delivery, toxicity, and immune responses before utilizing RNAs in a clinical setting. In this review, we provide an overview on opportunities and challenges for clinical translation of RNA-based therapeutics, with an emphasis on advances in novel delivery technologies and abdominal aortic aneurysm disease where non-coding RNAs have been shown to play a crucial regulatory role.

    View details for DOI 10.3389/fcvm.2021.571076

    View details for PubMedID 33937351

  • Urate, Blood Pressure, and Cardiovascular Disease: Evidence From Mendelian Randomization and Meta-Analysis of Clinical Trials. Hypertension (Dallas, Tex. : 1979) Gill, D., Cameron, A. C., Burgess, S., Li, X., Doherty, D. J., Karhunen, V., Abdul-Rahim, A. H., Taylor-Rowan, M., Zuber, V., Tsao, P. S., Klarin, D., VA Million Veteran Program, Evangelou, E., Elliott, P., Damrauer, S. M., Quinn, T. J., Dehghan, A., Theodoratou, E., Dawson, J., Tzoulaki, I. 2020: HYPERTENSIONAHA12016547

    Abstract

    Serum urate has been implicated in hypertension and cardiovascular disease, but it is not known whether it is exerting a causal effect. To investigate this, we performed Mendelian randomization analysis using data from UK Biobank, Million Veterans Program and genome-wide association study consortia, and meta-analysis of randomized controlled trials. The main Mendelian randomization analyses showed that every 1-SD increase in genetically predicted serum urate was associated with an increased risk of coronary heart disease (odds ratio, 1.19 [95% CI, 1.10-1.30]; P=4*10-5), peripheral artery disease (1.12 [95% CI, 1.03-1.21]; P=9*10-3), and stroke (1.11 [95% CI, 1.05-1.18]; P=2*10-4). In Mendelian randomization mediation analyses, elevated blood pressure was estimated to mediate approximately one-third of the effect of urate on cardiovascular disease risk. Systematic review and meta-analysis of randomized controlled trials showed a favorable effect of urate-lowering treatment on systolic blood pressure (mean difference, -2.55 mm Hg [95% CI, -4.06 to -1.05]; P=1*10-3) and major adverse cardiovascular events in those with previous cardiovascular disease (odds ratio, 0.40 [95% CI, 0.22-0.73]; P=3*10-3) but no significant effect on major adverse cardiovascular events in all individuals (odds ratio, 0.67 [95% CI, 0.44-1.03]; P=0.07). In summary, these Mendelian randomization and clinical trial data support an effect of higher serum urate on increasing blood pressure, which may mediate a consequent effect on cardiovascular disease risk. High-quality trials are necessary to provide definitive evidence on the specific clinical contexts where urate lowering may be of cardiovascular benefit.

    View details for DOI 10.1161/HYPERTENSIONAHA.120.16547

    View details for PubMedID 33356394

  • Discovery of rare variants associated with blood pressure regulation through meta-analysis of 1.3 million individuals. Nature genetics Surendran, P., Feofanova, E. V., Lahrouchi, N., Ntalla, I., Karthikeyan, S., Cook, J., Chen, L., Mifsud, B., Yao, C., Kraja, A. T., Cartwright, J. H., Hellwege, J. N., Giri, A., Tragante, V., Thorleifsson, G., Liu, D. J., Prins, B. P., Stewart, I. D., Cabrera, C. P., Eales, J. M., Akbarov, A., Auer, P. L., Bielak, L. F., Bis, J. C., Braithwaite, V. S., Brody, J. A., Daw, E. W., Warren, H. R., Drenos, F., Nielsen, S. F., Faul, J. D., Fauman, E. B., Fava, C., Ferreira, T., Foley, C. N., Franceschini, N., Gao, H., Giannakopoulou, O., Giulianini, F., Gudbjartsson, D. F., Guo, X., Harris, S. E., Havulinna, A. S., Helgadottir, A., Huffman, J. E., Hwang, S., Kanoni, S., Kontto, J., Larson, M. G., Li-Gao, R., Lindstrom, J., Lotta, L. A., Lu, Y., Luan, J., Mahajan, A., Malerba, G., Masca, N. G., Mei, H., Menni, C., Mook-Kanamori, D. O., Mosen-Ansorena, D., Muller-Nurasyid, M., Pare, G., Paul, D. S., Perola, M., Poveda, A., Rauramaa, R., Richard, M., Richardson, T. G., Sepulveda, N., Sim, X., Smith, A. V., Smith, J. A., Staley, J. R., Stanakova, A., Sulem, P., Theriault, S., Thorsteinsdottir, U., Trompet, S., Varga, T. V., Velez Edwards, D. R., Veronesi, G., Weiss, S., Willems, S. M., Yao, J., Young, R., Yu, B., Zhang, W., Zhao, J., Zhao, W., Zhao, W., Evangelou, E., Aeschbacher, S., Asllanaj, E., Blankenberg, S., Bonnycastle, L. L., Bork-Jensen, J., Brandslund, I., Braund, P. S., Burgess, S., Cho, K., Christensen, C., Connell, J., Mutsert, R. d., Dominiczak, A. F., Dorr, M., Eiriksdottir, G., Farmaki, A., Gaziano, J. M., Grarup, N., Grove, M. L., Hallmans, G., Hansen, T., Have, C. T., Heiss, G., Jorgensen, M. E., Jousilahti, P., Kajantie, E., Kamat, M., Karajamaki, A., Karpe, F., Koistinen, H. A., Kovesdy, C. P., Kuulasmaa, K., Laatikainen, T., Lannfelt, L., Lee, I., Lee, W., LifeLines Cohort Study, Linneberg, A., Martin, L. W., Moitry, M., Nadkarni, G., Neville, M. J., Palmer, C. N., Papanicolaou, G. J., Pedersen, O., Peters, J., Poulter, N., Rasheed, A., Rasmussen, K. L., Rayner, N. W., Magi, R., Renstrom, F., Rettig, R., Rossouw, J., Schreiner, P. J., Sever, P. S., Sigurdsson, E. L., Skaaby, T., Sun, Y. V., Sundstrom, J., Thorgeirsson, G., Esko, T., Trabetti, E., Tsao, P. S., Tuomi, T., Turner, S. T., Tzoulaki, I., Vaartjes, I., Vergnaud, A., Willer, C. J., Wilson, P. W., Witte, D. R., Yonova-Doing, E., Zhang, H., Aliya, N., Almgren, P., Amouyel, P., Asselbergs, F. W., Barnes, M. R., Blakemore, A. I., Boehnke, M., Bots, M. L., Bottinger, E. P., Buring, J. E., Chambers, J. C., Chen, Y. I., Chowdhury, R., Conen, D., Correa, A., Davey Smith, G., Boer, R. A., Deary, I. J., Dedoussis, G., Deloukas, P., Di Angelantonio, E., Elliott, P., EPIC-CVD, EPIC-InterAct, Felix, S. B., Ferrieres, J., Ford, I., Fornage, M., Franks, P. W., Franks, S., Frossard, P., Gambaro, G., Gaunt, T. R., Groop, L., Gudnason, V., Harris, T. B., Hayward, C., Hennig, B. J., Herzig, K., Ingelsson, E., Tuomilehto, J., Jarvelin, M., Jukema, J. W., Kardia, S. L., Kee, F., Kooner, J. S., Kooperberg, C., Launer, L. J., Lind, L., Loos, R. J., Majumder, A. A., Laakso, M., McCarthy, M. I., Melander, O., Mohlke, K. L., Murray, A. D., Nordestgaard, B. G., Orho-Melander, M., Packard, C. J., Padmanabhan, S., Palmas, W., Polasek, O., Porteous, D. J., Prentice, A. M., Province, M. A., Relton, C. L., Rice, K., Ridker, P. M., Rolandsson, O., Rosendaal, F. R., Rotter, J. I., Rudan, I., Salomaa, V., Samani, N. J., Sattar, N., Sheu, W. H., Smith, B. H., Soranzo, N., Spector, T. D., Starr, J. M., Sebert, S., Taylor, K. D., Lakka, T. A., Timpson, N. J., Tobin, M. D., Understanding Society Scientific Group, van der Harst, P., van der Meer, P., Ramachandran, V. S., Verweij, N., Virtamo, J., Volker, U., Weir, D. R., Zeggini, E., Charchar, F. J., Million Veteran Program, Wareham, N. J., Langenberg, C., Tomaszewski, M., Butterworth, A. S., Caulfield, M. J., Danesh, J., Edwards, T. L., Holm, H., Hung, A. M., Lindgren, C. M., Liu, C., Manning, A. K., Morris, A. P., Morrison, A. C., O'Donnell, C. J., Psaty, B. M., Saleheen, D., Stefansson, K., Boerwinkle, E., Chasman, D. I., Levy, D., Newton-Cheh, C., Munroe, P. B., Howson, J. M., de Boer, R. A., van der Harst, P., van der Meer, P., Verweij, N., Butterworth, A. S., Danesh, J., Langenberg, C., Deloukas, P., McCarthy, M. I., Franks, P. W., Rolandsson, O., Wareham, N. J., Prins, B. P., Zeggini, E., Hellwege, J. N., Giri, A., Edwards, D. R., Cho, K., Gaziano, J. M., Kovesdy, C. P., Sun, Y. V., Tsao, P. S., Wilson, P. W., Edwards, T. L., Hung, A. M., O'Donnell, C. J. 2020

    Abstract

    Genetic studies of blood pressure (BP) to date have mainly analyzed common variants (minor allele frequency>0.05). In a meta-analysis of up to ~1.3 million participants, we discovered 106 new BP-associated genomic regions and 87 rare (minor allele frequency≤0.01) variant BP associations (P<5*10-8), of which 32 were in new BP-associated loci and 55 were independent BP-associated single-nucleotide variants within known BP-associated regions. Average effects of rare variants (44% coding) were ~8 times larger than common variant effects and indicate potential candidate causal genes at new and known loci (for example, GATA5 and PLCB3). BP-associated variants (including rare and common) were enriched in regions of active chromatin in fetal tissues, potentially linking fetal development with BP regulation in later life. Multivariable Mendelian randomization suggested possible inverse effects of elevated systolic and diastolic BP on large artery stroke. Our study demonstrates the utility of rare-variant analyses for identifying candidate genes and the results highlight potential therapeutic targets.

    View details for DOI 10.1038/s41588-020-00713-x

    View details for PubMedID 33230300

  • Transfer learning enables prediction of CYP2D6 haplotype function. PLoS computational biology McInnes, G., Dalton, R., Sangkuhl, K., Whirl-Carrillo, M., Lee, S., Tsao, P. S., Gaedigk, A., Altman, R. B., Woodahl, E. L. 2020; 16 (11): e1008399

    Abstract

    Cytochrome P450 2D6 (CYP2D6) is a highly polymorphic gene whose protein product metabolizes more than 20% of clinically used drugs. Genetic variations in CYP2D6 are responsible for interindividual heterogeneity in drug response that can lead to drug toxicity and ineffective treatment, making CYP2D6 one of the most important pharmacogenes. Prediction of CYP2D6 phenotype relies on curation of literature-derived functional studies to assign a functional status to CYP2D6 haplotypes. As the number of large-scale sequencing efforts grows, new haplotypes continue to be discovered, and assignment of function is challenging to maintain. To address this challenge, we have trained a convolutional neural network to predict functional status of CYP2D6 haplotypes, called Hubble.2D6. Hubble.2D6 predicts haplotype function from sequence data and was trained using two pre-training steps with a combination of real and simulated data. We find that Hubble.2D6 predicts CYP2D6 haplotype functional status with 88% accuracy in a held-out test set and explains 47.5% of the variance in in vitro functional data among star alleles with unknown function. Hubble.2D6 may be a useful tool for assigning function to haplotypes with uncurated function, and used for screening individuals who are at risk of being poor metabolizers.

    View details for DOI 10.1371/journal.pcbi.1008399

    View details for PubMedID 33137098

  • The V122I Variant in Hereditary Transthyretin-Mediated Amyloidosis is Significantly Associated with Polyneuropathy Parker, M. M., Damrauer, S. M., Tcheandjieu, C., Erbe, D., Aldinc, E., Hawkins, P. N., Gillmore, J., Hull, L. E., Lynch, J. A., Joseph, J., Ticau, S., Flynn-Carroll, A. O., Deaton, A. M., Ward, L. D., Assimes, T. L., Tsao, P. S., Chang, K., Rader, D. J., Fitzgerald, K., Vaishnaw, A. K., Hinkle, G., Nioi, P. CHURCHILL LIVINGSTONE INC MEDICAL PUBLISHERS. 2020: S96
  • Mendelian Randomization Analysis of Hemostatic Factors and Their Contribution to Peripheral Artery Disease. Arteriosclerosis, thrombosis, and vascular biology Small, A. M., Huffman, J. E., Klarin, D., Sabater-Lleal, M., Lynch, J. A., Assimes, T. L., Sun, Y. V., Miller, D., Freiberg, M. S., Morrison, A. C., Rader, D. J., Wilson, P. W., Cho, K., Tsao, P. S., Chang, K., Smith, N. L., O'Donnell, C. J., de Vries, P. S., Damrauer, S. M., Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Hemostasis Working Group and the VA Million Veteran Program 2020: ATVBAHA119313847

    Abstract

    BACKGROUND: Peripheral artery disease (PAD) is the third most common form of atherosclerotic vascular disease and is characterized by significant functional disability and increased cardiovascular mortality. Recent genetic data support a role for a procoagulation protein variant, the factor V Leiden mutation, in PAD. The role of other hemostatic factors in PAD remains unknown.OBJECTIVE: To evaluate the role of hemostatic factors in PAD using Mendelian randomization. Approach and Results: Two-sample Mendelian randomization to evaluate the roles of FVII (factor VII), FVIII (factor VIII), FXI (factor XI), VWF (von Willebrand factor), and fibrinogen in PAD was performed using summary statistics from GWAS for hemostatic factors performed within the Cohorts for Heart and Aging Research in the Genome Epidemiology Consortium and from GWAS performed for PAD within the Million Veteran Program. Genetically determined FVIII and VWF, but not FVII, FXI, or fibrinogen, were associated with PAD in Mendelian randomization experiments (FVIII: odds ratio, 1.41 [95% CI, 1.23-1.62], P=6.0*10-7, VWF: odds ratio, 1.28 [95% CI, 1.07-1.52], P=0.0073). In single variant sensitivity analysis, the ABO locus was the strongest genetic instrument for both FVIII and VWF.CONCLUSIONS: Our results suggest a role for hemostasis, and by extension, thrombosis in PAD. Further study is warranted to determine whether VWF and FVIII independently affect the biology of PAD.

    View details for DOI 10.1161/ATVBAHA.119.313847

    View details for PubMedID 32847391

  • Minority-centric meta-analyses of blood lipid levels identify novel loci in the Population Architecture using Genomics and Epidemiology (PAGE) study PLOS GENETICS Hu, Y., Graff, M., Haessler, J., Buyske, S., Bien, S. A., Tao, R., Highland, H. M., Nishimura, K. K., Zubair, N., Lu, Y., Verbanck, M., Hilliard, A. T., Klarin, D., Damrauer, S. M., Ho, Y., Wilson, P. F., Chang, K., Tsao, P. S., Cho, K., O'Donnell, C. J., Assimes, T. L., Petty, L. E., Below, J. E., Dikilitas, O., Schaid, D. J., Kosel, M. L., Kullo, I. J., Rasmussen-Torvik, L. J., Jarvik, G. P., Feng, Q., Wei, W., Larson, E. B., Mentch, F. D., Almoguera, B., Sleiman, P. M., Raffield, L. M., Correa, A., Martin, L. W., Daviglus, M., Matise, T. C., Ambite, J., Carlson, C. S., Do, R., Loos, R. F., Wilkens, L. R., Le Marchand, L., Haiman, C., Stram, D. O., Hindorff, L. A., North, K. E., Kooperberg, C., Cheng, I., Peters, U., VA Million Veteran 2020; 16 (3)
  • Involvement of Myeloid Cells and Non-Coding RNA in Abdominal Aortic Aneurysm Disease. Antioxidants & redox signaling Knappich, C. n., Spin, J. M., Eckstein, H. H., Tsao, P. S., Maegdefessel, L. n. 2020

    Abstract

    Abdominal aortic aneurysm (AAA) is a potentially fatal condition, featuring the possibility of high-mortality rupture. To date, prophylactic surgery by means of open surgical repair (OSR) or endovascular aortic repair (EVAR) at specific thresholds are considered standard therapy. Both surgical options hold different risk profiles of short- and long-term morbidity and mortality. Targeting early stages of AAA development in order to decelerate disease progression is desirable. Recent Advances: Understanding the pathomechanisms that initiate formation, maintain growth, and promote rupture of AAA is crucial to developing new medical therapeutic options. Inflammatory cells, in particular macrophages, have been investigated for their contribution to AAA disease for decades, while evidence on lymphocytes, mast cells, and neutrophils is sparse. Recently, there has been increasing interest in non-coding RNAs (ncRNA) and their involvement in disease development, including AAA.The current evidence on myeloid cells and ncRNAs in AAA largely originates from small animal models, making clinical extrapolation difficult. Although it is feasible to collect surgical human AAA samples, these tissues reflect end-stage disease, preventing examination of critical mechanisms behind early AAA formation.Gaining more insight into how myeloid cells and ncRNAs contribute to AAA disease, particularly in early stages, might suggest non-surgical AAA treatment options. The utilization of large animal models might be helpful in this context to help bridge translational results to humans.

    View details for DOI 10.1089/ars.2020.8035

    View details for PubMedID 31989839

  • Discovery of 318 new risk loci for type 2 diabetes and related vascular outcomes among 1.4 million participants in a multi-ancestry meta-analysis. Nature genetics Vujkovic, M. n., Keaton, J. M., Lynch, J. A., Miller, D. R., Zhou, J. n., Tcheandjieu, C. n., Huffman, J. E., Assimes, T. L., Lorenz, K. n., Zhu, X. n., Hilliard, A. T., Judy, R. L., Huang, J. n., Lee, K. M., Klarin, D. n., Pyarajan, S. n., Danesh, J. n., Melander, O. n., Rasheed, A. n., Mallick, N. H., Hameed, S. n., Qureshi, I. H., Afzal, M. N., Malik, U. n., Jalal, A. n., Abbas, S. n., Sheng, X. n., Gao, L. n., Kaestner, K. H., Susztak, K. n., Sun, Y. V., DuVall, S. L., Cho, K. n., Lee, J. S., Gaziano, J. M., Phillips, L. S., Meigs, J. B., Reaven, P. D., Wilson, P. W., Edwards, T. L., Rader, D. J., Damrauer, S. M., O'Donnell, C. J., Tsao, P. S., Chang, K. M., Voight, B. F., Saleheen, D. n. 2020

    Abstract

    We investigated type 2 diabetes (T2D) genetic susceptibility via multi-ancestry meta-analysis of 228,499 cases and 1,178,783 controls in the Million Veteran Program (MVP), DIAMANTE, Biobank Japan and other studies. We report 568 associations, including 286 autosomal, 7 X-chromosomal and 25 identified in ancestry-specific analyses that were previously unreported. Transcriptome-wide association analysis detected 3,568 T2D associations with genetically predicted gene expression in 687 novel genes; of these, 54 are known to interact with FDA-approved drugs. A polygenic risk score (PRS) was strongly associated with increased risk of T2D-related retinopathy and modestly associated with chronic kidney disease (CKD), peripheral artery disease (PAD) and neuropathy. We investigated the genetic etiology of T2D-related vascular outcomes in the MVP and observed statistical SNP-T2D interactions at 13 variants, including coronary heart disease (CHD), CKD, PAD and neuropathy. These findings may help to identify potential therapeutic targets for T2D and genomic pathways that link T2D to vascular outcomes.

    View details for DOI 10.1038/s41588-020-0637-y

    View details for PubMedID 32541925

  • Validating a non-invasive, ALT-based non-alcoholic fatty liver phenotype in the million veteran program. PloS one Serper, M. n., Vujkovic, M. n., Kaplan, D. E., Carr, R. M., Lee, K. M., Shao, Q. n., Miller, D. R., Reaven, P. D., Phillips, L. S., O'Donnell, C. J., Meigs, J. B., Wilson, P. W., Vickers-Smith, R. n., Kranzler, H. R., Justice, A. C., Gaziano, J. M., Muralidhar, S. n., Pyarajan, S. n., DuVall, S. L., Assimes, T. L., Lee, J. S., Tsao, P. S., Rader, D. J., Damrauer, S. M., Lynch, J. A., Saleheen, D. n., Voight, B. F., Chang, K. M. 2020; 15 (8): e0237430

    Abstract

    Given ongoing challenges in non-invasive non-alcoholic liver disease (NAFLD) diagnosis, we sought to validate an ALT-based NAFLD phenotype using measures readily available in electronic health records (EHRs) and population-based studies by leveraging the clinical and genetic data in the Million Veteran Program (MVP), a multi-ethnic mega-biobank of US Veterans.MVP participants with alanine aminotransferases (ALT) >40 units/L for men and >30 units/L for women without other causes of liver disease were compared to controls with normal ALT. Genetic variants spanning eight NAFLD risk or ALT-associated loci (LYPLAL1, GCKR, HSD17B13, TRIB1, PPP1R3B, ERLIN1, TM6SF2, PNPLA3) were tested for NAFLD associations with sensitivity analyses adjusting for metabolic risk factors and alcohol consumption. A manual EHR review assessed performance characteristics of the NAFLD phenotype with imaging and biopsy data as gold standards. Genetic associations with advanced fibrosis were explored using FIB4, NAFLD Fibrosis Score and platelet counts.Among 322,259 MVP participants, 19% met non-invasive criteria for NAFLD. Trans-ethnic meta-analysis replicated associations with previously reported genetic variants in all but LYPLAL1 and GCKR loci (P<6x10-3), without attenuation when adjusted for metabolic risk factors and alcohol consumption. At the previously reported LYPLAL1 locus, the established genetic variant did not appear to be associated with NAFLD, however the regional association plot showed a significant association with NAFLD 279kb downstream. In the EHR validation, the ALT-based NAFLD phenotype yielded a positive predictive value 0.89 and 0.84 for liver biopsy and abdominal imaging, respectively (inter-rater reliability (Cohen's kappa = 0.98)). HSD17B13 and PNPLA3 loci were associated with advanced fibrosis.We validate a simple, non-invasive ALT-based NAFLD phenotype using EHR data by leveraging previously established NAFLD risk-associated genetic polymorphisms.

    View details for DOI 10.1371/journal.pone.0237430

    View details for PubMedID 32841307

  • Cross-trait analyses with migraine reveal widespread pleiotropy and suggest a vascular component to migraine headache. International journal of epidemiology Siewert, K. M., Klarin, D. n., Damrauer, S. M., Chang, K. M., Tsao, P. S., Assimes, T. L., Davey-Smith, G. n., Voight, B. F. 2020

    Abstract

    Nearly a fifth of the world's population suffer from migraine headache, yet risk factors for this disease are poorly characterized.To further elucidate these factors, we conducted a genetic correlation analysis using cross-trait linkage disequilibrium (LD) score regression between migraine headache and 47 traits from the UK Biobank. We then tested for possible causality between these phenotypes and migraine, using Mendelian randomization. In addition, we attempted replication of our findings in an independent genome-wide association study (GWAS) when available.We report multiple phenotypes with genetic correlation (P  < 1.06 × 10-3) with migraine, including heart disease, type 2 diabetes, lipid levels, blood pressure, autoimmune and psychiatric phenotypes. In particular, we find evidence that blood pressure directly contributes to migraine and explains a previously suggested causal relationship between calcium and migraine.This is the largest genetic correlation analysis of migraine headache to date, both in terms of migraine GWAS sample size and the number of phenotypes tested. We find that migraine has a shared genetic basis with a large number of traits, indicating pervasive pleiotropy at migraine-associated loci.

    View details for DOI 10.1093/ije/dyaa050

    View details for PubMedID 32306029

  • Genotyping Array Design and Data Quality Control in the Million Veteran Program. American journal of human genetics Hunter-Zinck, H. n., Shi, Y. n., Li, M. n., Gorman, B. R., Ji, S. G., Sun, N. n., Webster, T. n., Liem, A. n., Hsieh, P. n., Devineni, P. n., Karnam, P. n., Gong, X. n., Radhakrishnan, L. n., Schmidt, J. n., Assimes, T. L., Huang, J. n., Pan, C. n., Humphries, D. n., Brophy, M. n., Moser, J. n., Muralidhar, S. n., Huang, G. D., Przygodzki, R. n., Concato, J. n., Gaziano, J. M., Gelernter, J. n., O'Donnell, C. J., Hauser, E. R., Zhao, H. n., O'Leary, T. J., Tsao, P. S., Pyarajan, S. n. 2020; 106 (4): 535–48

    Abstract

    The Million Veteran Program (MVP), initiated by the Department of Veterans Affairs (VA), aims to collect biosamples with consent from at least one million veterans. Presently, blood samples have been collected from over 800,000 enrolled participants. The size and diversity of the MVP cohort, as well as the availability of extensive VA electronic health records, make it a promising resource for precision medicine. MVP is conducting array-based genotyping to provide a genome-wide scan of the entire cohort, in parallel with whole-genome sequencing, methylation, and other 'omics assays. Here, we present the design and performance of the MVP 1.0 custom Axiom array, which was designed and developed as a single assay to be used across the multi-ethnic MVP cohort. A unified genetic quality-control analysis was developed and conducted on an initial tranche of 485,856 individuals, leading to a high-quality dataset of 459,777 unique individuals. 668,418 genetic markers passed quality control and showed high-quality genotypes not only on common variants but also on rare variants. We confirmed that, with non-European individuals making up nearly 30%, MVP's substantial ancestral diversity surpasses that of other large biobanks. We also demonstrated the quality of the MVP dataset by replicating established genetic associations with height in European Americans and African Americans ancestries. This current dataset has been made available to approved MVP researchers for genome-wide association studies and other downstream analyses. Further data releases will be available for analysis as recruitment at the VA continues and the cohort expands both in size and diversity.

    View details for DOI 10.1016/j.ajhg.2020.03.004

    View details for PubMedID 32243820

  • Hyperlipidemia does not affect development of elastase-induced abdominal aortic aneurysm in mice. Atherosclerosis Mulorz, J. n., Spin, J. M., Beck, H. C., Tha Thi, M. L., Wagenhäuser, M. U., Rasmussen, L. M., Lindholt, J. S., Tsao, P. S., Steffensen, L. B. 2020; 311: 73–83

    Abstract

    Hyperlipidemia is a suggested risk factor for abdominal aortic aneurysm (AAA). However, whether hyperlipidemia is causally involved in AAA progression remains elusive. Here, we tested the hypothesis that hyperlipidemia aggravates AAA formation in the widely used porcine pancreatic elastase (PPE) model of AAA in mice with varying levels of plasma lipids.Prior to PPE-surgery, 8-week-old male C57BL/6J mice (n = 32) received 1·1011 viral genomes of rAAV8-D377Y-mPcsk9 or control rAAV8 via the tail vein. Mice were fed either western type diet or regular chow. At baseline and during the 28 days following PPE-surgery, mice underwent weekly ultrasonic assessment of AAA progression. Experiments were repeated using Apolipoprotein E knockout (ApoE-/-) mice (n = 7) and wildtype C57BL/6J mice (n = 5).At sacrifice, maximal intergroup plasma cholesterol and non-HDL/HDL ratio differences were >5-fold and >20-fold, respectively. AAA diameters expanded to 150% of baseline, but no intergroup differences were detected. This was verified in an independent experiment comparing 8-week-old male ApoE-/- mice with wildtype mice. Histological evaluation of experimental AAA lesions revealed accumulated lipid in neointimal and medial layers, and analysis of human AAA lesions (n = 5) obtained from open repair showed medial lipid deposition.In summary, we find that lipid deposition in the aortic wall is a feature of PPE-induced AAA in mice as well as human AAA lesions. Despite, our data do not support the hypothesis that hyperlipidemia contributes to AAA progression.

    View details for DOI 10.1016/j.atherosclerosis.2020.08.012

    View details for PubMedID 32949946

  • The relationship between circulating lipids and breast cancer risk: A Mendelian randomization study. PLoS medicine Johnson, K. E., Siewert, K. M., Klarin, D. n., Damrauer, S. M., Chang, K. M., Tsao, P. S., Assimes, T. L., Maxwell, K. N., Voight, B. F. 2020; 17 (9): e1003302

    Abstract

    A number of epidemiological and genetic studies have attempted to determine whether levels of circulating lipids are associated with risks of various cancers, including breast cancer (BC). However, it remains unclear whether a causal relationship exists between lipids and BC. If alteration of lipid levels also reduced risk of BC, this could present a target for disease prevention. This study aimed to assess a potential causal relationship between genetic variants associated with plasma lipid traits (high-density lipoprotein, HDL; low-density lipoprotein, LDL; triglycerides, TGs) with risk for BC using Mendelian randomization (MR).Data from genome-wide association studies in up to 215,551 participants from the Million Veteran Program (MVP) were used to construct genetic instruments for plasma lipid traits. The effect of these instruments on BC risk was evaluated using genetic data from the BCAC (Breast Cancer Association Consortium) based on 122,977 BC cases and 105,974 controls. Using MR, we observed that a 1-standard-deviation genetically determined increase in HDL levels is associated with an increased risk for all BCs (HDL: OR [odds ratio] = 1.08, 95% confidence interval [CI] = 1.04-1.13, P < 0.001). Multivariable MR analysis, which adjusted for the effects of LDL, TGs, body mass index (BMI), and age at menarche, corroborated this observation for HDL (OR = 1.06, 95% CI = 1.03-1.10, P = 4.9 × 10-4) and also found a relationship between LDL and BC risk (OR = 1.03, 95% CI = 1.01-1.07, P = 0.02). We did not observe a difference in these relationships when stratified by breast tumor estrogen receptor (ER) status. We repeated this analysis using genetic variants independent of the leading association at core HDL pathway genes and found that these variants were also associated with risk for BCs (OR = 1.11, 95% CI = 1.06-1.16, P = 1.5 × 10-6), including locus-specific associations at ABCA1 (ATP Binding Cassette Subfamily A Member 1), APOE-APOC1-APOC4-APOC2 (Apolipoproteins E, C1, C4, and C2), and CETP (Cholesteryl Ester Transfer Protein). In addition, we found evidence that genetic variation at the ABO locus is associated with both lipid levels and BC. Through multiple statistical approaches, we minimized and tested for the confounding effects of pleiotropy and population stratification on our analysis; however, the possible existence of residual pleiotropy and stratification remains a limitation of this study.We observed that genetically elevated plasma HDL and LDL levels appear to be associated with increased BC risk. Future studies are required to understand the mechanism underlying this putative causal relationship, with the goal of developing potential therapeutic strategies aimed at altering the cholesterol-mediated effect on BC risk.

    View details for DOI 10.1371/journal.pmed.1003302

    View details for PubMedID 32915777

  • Genetic determinants of increased body mass index mediate the effect of smoking on increased risk for type 2 diabetes risk but not coronary artery disease. Human molecular genetics Thom, C. S., Ding, Z. n., Levin, M. G., Damrauer, S. M., Lee, K. M., Lynch, J. n., Chang, K. M., Tsao, P. S., Cho, K. n., Wilson, P. W., Assimes, T. L., Sun, Y. V., O'Donnell, C. J., Vujkovic, M. n., Voight, B. F. 2020

    Abstract

    Clinical observations have linked tobacco smoking with increased type 2 diabetes risk. Mendelian randomization analysis has recently suggested smoking may be a causal risk factor for type 2 diabetes. However, this association could be mediated by additional risk factors correlated with smoking behavior, which have not been investigated. We hypothesized that body mass index (BMI) could help to explain the association between smoking and diabetes risk. First, we confirmed that genetic determinants of smoking initiation increased risk for type 2 diabetes (OR = 1.21, 95% CI: 1.15-1.27, P = 1 × 10-12) and coronary artery disease (CAD; OR = 1.21, 95% CI: 1.16-1.26, P = 2 × 10-20). Additionally, 2-fold increased smoking risk was positively associated with increased BMI (~0.8 kg/m2, 95% CI: 0.54-0.98 kg/m2, P = 1.8 × 10-11). Multivariable Mendelian randomization analyses showed that BMI accounted for nearly all the risk smoking exerted on type 2 diabetes (OR 1.06, 95% CI: 1.01-1.11, P = 0.03). In contrast, the independent effect of smoking on increased CAD risk persisted (OR 1.12, 95% CI: 1.08-1.17, P = 3 × 10-8). Causal mediation analyses agreed with these estimates. Furthermore, analysis using individual-level data from the Million Veteran Program (MVP) independently replicated the association of smoking behavior with CAD (OR 1.24, 95% CI: 1.12-1.37, P = 2 × 10-5), but not type 2 diabetes (OR 0.98, 95% CI: 0.89-1.08, P = 0.69), after controlling for BMI. Our findings support a model whereby genetic determinants of smoking increase type 2 diabetes risk indirectly through their relationship with obesity. Smokers should be advised to stop smoking to limit type 2 diabetes and CAD risk. Therapeutic efforts should consider pathophysiology relating smoking and obesity.

    View details for DOI 10.1093/hmg/ddaa193

    View details for PubMedID 32833022

  • Minority-centric meta-analyses of blood lipid levels identify novel loci in the Population Architecture using Genomics and Epidemiology (PAGE) study. PLoS genetics Hu, Y. n., Graff, M. n., Haessler, J. n., Buyske, S. n., Bien, S. A., Tao, R. n., Highland, H. M., Nishimura, K. K., Zubair, N. n., Lu, Y. n., Verbanck, M. n., Hilliard, A. T., Klarin, D. n., Damrauer, S. M., Ho, Y. L., Wilson, P. W., Chang, K. M., Tsao, P. S., Cho, K. n., O'Donnell, C. J., Assimes, T. L., Petty, L. E., Below, J. E., Dikilitas, O. n., Schaid, D. J., Kosel, M. L., Kullo, I. J., Rasmussen-Torvik, L. J., Jarvik, G. P., Feng, Q. n., Wei, W. Q., Larson, E. B., Mentch, F. D., Almoguera, B. n., Sleiman, P. M., Raffield, L. M., Correa, A. n., Martin, L. W., Daviglus, M. n., Matise, T. C., Ambite, J. L., Carlson, C. S., Do, R. n., Loos, R. J., Wilkens, L. R., Le Marchand, L. n., Haiman, C. n., Stram, D. O., Hindorff, L. A., North, K. E., Kooperberg, C. n., Cheng, I. n., Peters, U. n. 2020; 16 (3): e1008684

    Abstract

    Lipid levels are important markers for the development of cardio-metabolic diseases. Although hundreds of associated loci have been identified through genetic association studies, the contribution of genetic factors to variation in lipids is not fully understood, particularly in U.S. minority groups. We performed genome-wide association analyses for four lipid traits in over 45,000 ancestrally diverse participants from the Population Architecture using Genomics and Epidemiology (PAGE) Study, followed by a meta-analysis with several European ancestry studies. We identified nine novel lipid loci, five of which showed evidence of replication in independent studies. Furthermore, we discovered one novel gene in a PrediXcan analysis, minority-specific independent signals at eight previously reported loci, and potential functional variants at two known loci through fine-mapping. Systematic examination of known lipid loci revealed smaller effect estimates in African American and Hispanic ancestry populations than those in Europeans, and better performance of polygenic risk scores based on minority-specific effect estimates. Our findings provide new insight into the genetic architecture of lipid traits and highlight the importance of conducting genetic studies in diverse populations in the era of precision medicine.

    View details for DOI 10.1371/journal.pgen.1008684

    View details for PubMedID 32226016

  • PCSK9 loss of function is protective against extra-coronary atherosclerotic cardiovascular disease in a large multi-ethnic cohort. PloS one Small, A. M., Huffman, J. E., Klarin, D. n., Lynch, J. A., Assimes, T. n., DuVall, S. n., Sun, Y. V., Shere, L. n., Natarajan, P. n., Gaziano, M. n., Rader, D. J., Wilson, P. W., Tsao, P. S., Chang, K. M., Cho, K. n., O'Donnell, C. J., Casas, J. P., Damrauer, S. M. 2020; 15 (11): e0239752

    Abstract

    Therapeutic inhibition of PCSK9 protects against coronary artery disease (CAD) and ischemic stroke (IS). The impact on other diseases remains less well characterized.We created a genetic risk score (GRS) for PCSK9 using four single nucleotide polymorphisms (SNPs) at or near the PCSK9 locus known to impact lower LDL-Cholesterol (LDL-C): rs11583680, rs11591147, rs2479409, and rs11206510. We then used our GRS to calculate weighted odds ratios reflecting the impact of a genetically determined 10 mg/dL decrease in LDL-C on several pre-specified phenotypes including CAD, IS, peripheral artery disease (PAD), abdominal aortic aneurysm (AAA), type 2 diabetes, dementia, chronic obstructive pulmonary disease, and cancer. Finally, we used our weighted GRS to perform a phenome-wide association study.Genetic and electronic health record data that passed quality control was available in 312,097 individuals, (227,490 White participants, 58,907 Black participants, and 25,700 Hispanic participants). PCSK9 mediated reduction in LDL-C was associated with a reduced risk of CAD and AAA in trans-ethnic meta-analysis (CAD OR 0.83 [95% CI 0.80-0.87], p = 6.0 x 10-21; AAA OR 0.76 [95% CI 0.68-0.86], p = 2.9 x 10-06). Significant protective effects were noted for PAD in White individuals (OR 0.83 [95% CI 0.71-0.97], p = 2.3 x 10-04) but not in other genetic ancestries. Genetically reduced PCSK9 function associated with a reduced risk of dementia in trans-ethnic meta-analysis (OR 0.86 [95% CI 0.78-0.93], p = 5.0 x 10-04).Genetically reduced PCSK9 function results in a reduction in risk of several important extra-coronary atherosclerotic phenotypes in addition to known effects on CAD and IS, including PAD and AAA. We also highlight a novel reduction in risk of dementia, supporting a well-recognized vascular component to cognitive impairment and an opportunity for therapeutic repositioning.

    View details for DOI 10.1371/journal.pone.0239752

    View details for PubMedID 33166319

  • Genome-wide association analysis of venous thromboembolism identifies new risk loci and genetic overlap with arterial vascular disease. Nature genetics Klarin, D., Busenkell, E., Judy, R., Lynch, J., Levin, M., Haessler, J., Aragam, K., Chaffin, M., Haas, M., Lindstrom, S., Assimes, T. L., Huang, J., Min Lee, K., Shao, Q., Huffman, J. E., Kabrhel, C., Huang, Y., Sun, Y. V., Vujkovic, M., Saleheen, D., Miller, D. R., Reaven, P., DuVall, S., Boden, W. E., Pyarajan, S., Reiner, A. P., Tregouet, D., Henke, P., Kooperberg, C., Gaziano, J. M., Concato, J., Rader, D. J., Cho, K., Chang, K., Wilson, P. W., Smith, N. L., O'Donnell, C. J., Tsao, P. S., Kathiresan, S., Obi, A., Damrauer, S. M., Natarajan, P., INVENT Consortium, Veterans Affairs Million Veteran Program 2019

    Abstract

    Venous thromboembolism is a significant cause of mortality1, yet its genetic determinants are incompletely defined. We performed a discovery genome-wide association study in the Million Veteran Program and UK Biobank, with testing of approximately 13 million DNA sequence variants for association with venous thromboembolism (26,066 cases and 624,053 controls) and meta-analyzed both studies, followed by independent replication with up to 17,672 venous thromboembolism cases and 167,295 controls. We identified 22 previously unknown loci, bringing the total number of venous thromboembolism-associated loci to 33, and subsequently fine-mapped these associations. We developed a genome-wide polygenic risk score for venous thromboembolism that identifies 5% of the population at an equivalent incident venous thromboembolism risk to carriers of the established factor V Leiden p.R506Q and prothrombin G20210A mutations. Our data provide mechanistic insights into the genetic epidemiology of venous thromboembolism and suggest a greater overlap among venous and arterial cardiovascular disease than previously thought.

    View details for DOI 10.1038/s41588-019-0519-3

    View details for PubMedID 31676865

  • Mapping eGFR loci to the renal transcriptome and phenome in the VA Million Veteran Program. Nature communications Hellwege, J. N., Velez Edwards, D. R., Giri, A., Qiu, C., Park, J., Torstenson, E. S., Keaton, J. M., Wilson, O. D., Robinson-Cohen, C., Chung, C. P., Roumie, C. L., Klarin, D., Damrauer, S. M., DuVall, S. L., Siew, E., Akwo, E. A., Wuttke, M., Gorski, M., Li, M., Li, Y., Gaziano, J. M., Wilson, P. W., Tsao, P. S., O'Donnell, C. J., Kovesdy, C. P., Pattaro, C., Kottgen, A., Susztak, K., Edwards, T. L., Hung, A. M. 2019; 10 (1): 3842

    Abstract

    Chronic kidney disease (CKD),defined by low estimated glomerular filtration rate (eGFR), contributes to global morbidity and mortality. Here we conduct a transethnic Genome-Wide Association Study of eGFR in 280,722 participants of the Million Veteran Program (MVP), with replication in 765,289 participants from the Chronic Kidney Disease Genetics (CKDGen) Consortium. We identify 82 previously unreported variants, confirm 54 loci, and report interesting findings including association of the sickle cell allele of betaglobin among non-Hispanic blacks. Our transcriptome-wide association study of kidney function in healthy kidney tissue identifies 36 previously unreported and nine known genes, and maps gene expression to renal cell types. In a Phenome-Wide Association Study in 192,868 MVP participants using a weighted genetic score we detect associations with CKD stages and complications and kidney stones. This investigation reinterprets the genetic architecture of kidney function to identify the gene, tissue, and anatomical context of renal homeostasis and the clinical consequences of dysregulation.

    View details for DOI 10.1038/s41467-019-11704-w

    View details for PubMedID 31451708

  • Author Correction: Genome-wide association study of alcohol consumption and use disorder in 274,424 individuals from multiple populations. Nature communications Kranzler, H. R., Zhou, H., Kember, R. L., Smith, R. V., Justice, A. C., Damrauer, S., Tsao, P. S., Klarin, D., Baras, A., Reid, J., Overton, J., Rader, D. J., Cheng, Z., Tate, J. P., Becker, W. C., Concato, J., Xu, K., Polimanti, R., Zhao, H., Gelernter, J. 2019; 10 (1): 2275

    Abstract

    The original version of this Article omitted the following from the Acknowledgements: 'Supported by the Mental Illness Research, Education and Clinical Center of the Veterans Integrated Service Network 4 of the Department of Veterans Affairs.' This has now been corrected in both the PDF and HTML versions of the Article.

    View details for DOI 10.1038/s41467-019-10254-5

    View details for PubMedID 31101824

  • Controlled isoflurane anesthesia exposure is required for reliable behavioral testing in murine surgical models. Journal of pharmacological sciences Toyama, K., Spin, J. M., Abe, Y., Suzuki, Y., Deng, A. C., Wagenhauser, M. U., Yoshino, T., Mulorz, J., Liu, S., Tsao, P. S., Mogi, M. 2019

    Abstract

    We investigated the effects of variations in anesthesia exposure time prior to conducting anxiety response behavioral testing in sham controls from an experimental murine model. The staying time in the center area of the Open Field test in the "long exposure" group was significantly decreased compared to that of the "short exposure" group. Significant correlation was found between anesthesia time and the duration of staying time in the center area. We conclude that anesthesia time may have a significant impact on behavioral anxiety testing in this context, and advise careful control of this parameter in protocol optimization in related surgical animal models.

    View details for DOI 10.1016/j.jphs.2019.03.007

    View details for PubMedID 31133404

  • Genome-wide association study of alcohol consumption and use disorder in 274,424 individuals from multiple populations NATURE COMMUNICATIONS Kranzler, H. R., Zhou, H., Kember, R. L., Smith, R., Justice, A. C., Damrauer, S., Tsao, P. S., Klarin, D., Baras, A., Reid, J., Oyerton, J., Rader, D. J., Cheng, Z., Tate, J. P., Becker, W. C., Concato, J., Xu, K., Polimanti, R., Zhao, H., Gelernter, J. 2019; 10
  • An Automated Algorithm to Quantify Collagen Distribution in Aortic Wall JOURNAL OF HISTOCHEMISTRY & CYTOCHEMISTRY Nguyen, D. M., Wagenhauser, M. U., Mehrkens, D., Adam, M., Tsao, P. S., Ramasubramanian, A. K. 2019; 67 (4): 267–74
  • microRNA-based biomarker for dementia AGING-US Toyama, K., Mogi, M., Tsao, P. S. 2019; 11 (5): 1329–30
  • microRNA-based biomarker for dementia. Aging Toyama, K., Mogi, M., Tsao, P. S. 2019

    View details for PubMedID 30867338

  • Non-coding RNAs in aneurysmal aortopathy VASCULAR PHARMACOLOGY Spin, J. M., Li, D. Y., Maegdefessel, L., Tsao, P. S. 2019; 114: 110–21
  • Association of APOL1 Risk Alleles with Cardiovascular Disease in African Americans in the Million Veteran Program. Circulation Bick, A. G., Akwo, E. n., Robinson-Cohen, C. n., Lee, K. n., Lynch, J. n., Assimes, T. L., DuVall, S. n., Edwards, T. n., Fang, H. n., Freiberg, S. M., Giri, A. n., Huffman, J. E., Huang, J. n., Hull, L. n., Kember, R. L., Klarin, D. n., Lee, J. S., Levin, M. n., Miller, D. R., Natarajan, P. n., Saleheen, D. n., Shao, Q. n., Sun, Y. V., Tang, H. n., Wilson, O. n., Chang, K. M., Cho, K. n., Concato, J. n., Gaziano, J. M., Kathiresan, S. n., O'Donnell, C. J., Rader, D. J., Tsao, P. S., Wilson, P. W., Hung, A. M., Damrauer, S. M. 2019

    Abstract

    Approximately 13% of African-American individuals carry two copies of the APOL1 risk alleles G1 or G2, which are associated with 1.5-2.5 fold increased risk of chronic kidney disease (CKD). There have been conflicting reports as to whether an association exists between APOL1 risk alleles and cardiovascular disease, independent of the effects of APOL1 on kidney disease. We sought to test the association of APOL1 G1/G2 alleles with coronary artery disease (CAD), peripheral artery disease (PAD), and stroke among African American individuals in the Million Veteran Program (MVP).We performed a time-to-event analysis of retrospective electronic health record (EHR) data using Cox proportional hazard and competing risks Fine and Gray sub-distribution hazard models. The primary exposure was APOL1 risk allele status. The primary outcome was incident CAD amongst individuals without CKD during the 12.5 year follow up period. Separately we analyzed the cross-sectional association of APOL1 risk allele status with lipid traits and 115 cardiovascular diseases using phenome-wide association.Among 30,903 African American MVP participants, 3,941 (13%) carried the two APOL1 risk allele high-risk genotype. Individuals with normal kidney function at baseline with two risk alleles had slightly higher risk of developing CAD compared to those with no risk alleles (Hazard Ratio (HR): 1.11, 95% Confidence Interval (CI): 1.01-1.21, p=0.039). Similarly, modest associations were identified with incident stroke (HR: 1.20, 95% CI: 1.05-1.36, p=0.007) and PAD (HR: 1.15, 95% CI:1.01-1.29, p=0.031). When modeling both cardiovascular and renal outcomes, APOL1 was strongly associated with incident renal disease, while no significant association with the cardiovascular disease endpoints could be detected. Cardiovascular phenome-wide association analyses did not identify additional significant associations with cardiovascular disease subsets.APOL1 risk variants display a modest association with cardiovascular disease and this association is likely mediated by the known APOL1 association with CKD.

    View details for DOI 10.1161/CIRCULATIONAHA.118.036589

    View details for PubMedID 31337231

  • Author Correction: Genome-wide association study of alcohol consumption and use disorder in 274,424 individuals from multiple populations. Nature communications Kranzler, H. R., Zhou, H. n., Kember, R. L., Smith, R. V., Justice, A. C., Damrauer, S. n., Tsao, P. S., Klarin, D. n., Baras, A. n., Reid, J. n., Overton, J. n., Rader, D. J., Cheng, Z. n., Tate, J. P., Becker, W. C., Concato, J. n., Xu, K. n., Polimanti, R. n., Zhao, H. n., Gelernter, J. n. 2019; 10 (1): 4050

    Abstract

    An amendment to this paper has been published and can be accessed via a link at the top of the paper.

    View details for DOI 10.1038/s41467-019-11916-0

    View details for PubMedID 31481659

  • Harmonizing Genetic Ancestry and Self-identified Race/Ethnicity in Genome-wide Association Studies. American journal of human genetics Fang, H. n., Hui, Q. n., Lynch, J. n., Honerlaw, J. n., Assimes, T. L., Huang, J. n., Vujkovic, M. n., Damrauer, S. M., Pyarajan, S. n., Gaziano, J. M., DuVall, S. L., O'Donnell, C. J., Cho, K. n., Chang, K. M., Wilson, P. W., Tsao, P. S., Sun, Y. V., Tang, H. n. 2019

    Abstract

    Large-scale multi-ethnic cohorts offer unprecedented opportunities to elucidate the genetic factors influencing complex traits related to health and disease among minority populations. At the same time, the genetic diversity in these cohorts presents new challenges for analysis and interpretation. We consider the utility of race and/or ethnicity categories in genome-wide association studies (GWASs) of multi-ethnic cohorts. We demonstrate that race/ethnicity information enhances the ability to understand population-specific genetic architecture. To address the practical issue that self-identified racial/ethnic information may be incomplete, we propose a machine learning algorithm that produces a surrogate variable, termed HARE. We use height as a model trait to demonstrate the utility of HARE and ethnicity-specific GWASs.

    View details for DOI 10.1016/j.ajhg.2019.08.012

    View details for PubMedID 31564439

  • Blood Leukocyte DNA Methylation Predicts Risk of Future Myocardial Infarction and Coronary Heart Disease. Circulation Agha, G. n., Mendelson, M. M., Ward-Caviness, C. K., Joehanes, R. n., Huan, T. n., Gondalia, R. n., Salfati, E. n., Brody, J. A., Fiorito, G. n., Bressler, J. n., Chen, B. H., Ligthart, S. n., Guarrera, S. n., Colicino, E. n., Just, A. C., Wahl, S. n., Gieger, C. n., Vandiver, A. R., Tanaka, T. n., Hernandez, D. G., Pilling, L. C., Singleton, A. B., Sacerdote, C. n., Krogh, V. n., Panico, S. n., Tumino, R. n., Li, Y. n., Zhang, G. n., Stewart, J. D., Floyd, J. S., Wiggins, K. L., Rotter, J. I., Multhaup, M. n., Bakulski, K. n., Horvath, S. n., Tsao, P. S., Absher, D. M., Vokonas, P. n., Hirschhorn, J. n., Fallin, M. D., Liu, C. n., Bandinelli, S. n., Boerwinkle, E. n., Dehghan, A. n., Schwartz, J. D., Psaty, B. M., Feinberg, A. P., Hou, L. n., Ferrucci, L. n., Sotoodehnia, N. n., Matullo, G. n., Peters, A. n., Fornage, M. n., Assimes, T. L., Whitsel, E. A., Levy, D. n., Baccarelli, A. A. 2019; 140 (8): 645–57

    Abstract

    DNA methylation is implicated in coronary heart disease (CHD), but current evidence is based on small, cross-sectional studies. We examined blood DNA methylation in relation to incident CHD across multiple prospective cohorts.Nine population-based cohorts from the United States and Europe profiled epigenome-wide blood leukocyte DNA methylation using the Illumina Infinium 450k microarray, and prospectively ascertained CHD events including coronary insufficiency/unstable angina, recognized myocardial infarction, coronary revascularization, and coronary death. Cohorts conducted race-specific analyses adjusted for age, sex, smoking, education, body mass index, blood cell type proportions, and technical variables. We conducted fixed-effect meta-analyses across cohorts.Among 11 461 individuals (mean age 64 years, 67% women, 35% African American) free of CHD at baseline, 1895 developed CHD during a mean follow-up of 11.2 years. Methylation levels at 52 CpG (cytosine-phosphate-guanine) sites were associated with incident CHD or myocardial infarction (false discovery rate<0.05). These CpGs map to genes with key roles in calcium regulation (ATP2B2, CASR, GUCA1B, HPCAL1), and genes identified in genome- and epigenome-wide studies of serum calcium (CASR), serum calcium-related risk of CHD (CASR), coronary artery calcified plaque (PTPRN2), and kidney function (CDH23, HPCAL1), among others. Mendelian randomization analyses supported a causal effect of DNA methylation on incident CHD; these CpGs map to active regulatory regions proximal to long non-coding RNA transcripts.Methylation of blood-derived DNA is associated with risk of future CHD across diverse populations and may serve as an informative tool for gaining further insight on the development of CHD.

    View details for DOI 10.1161/CIRCULATIONAHA.118.039357

    View details for PubMedID 31424985

  • Trans-ethnic association study of blood pressure determinants in over 750,000 individuals NATURE GENETICS Giri, A., Hellwege, J. N., Keaton, J. M., Park, J., Qiu, C., Warren, H. R., Torstenson, E. S., Kovesdy, C. P., Sun, Y. V., Wilson, O. D., Robinson-Cohen, C., Roumie, C. L., Chung, C. P., Birdwell, K. A., Damrauer, S. M., DuVall, S. L., Klarin, D., Cho, K., Wang, Y., Evangelou, E., Cabrera, C. P., Wain, L. V., Shrestha, R., Mautz, B. S., Akwo, E. A., Sargurupremraj, M., Debette, S., Boehnke, M., Scott, L. J., Luan, J., Zhao, J., Willems, S. M., Theriault, S., Shah, N., Oldmeadow, C., Almgren, P., Li-Gao, R., Verweij, N., Boutin, T. S., Mangino, M., Ntalla, I., Feofanova, E., Surendran, P., Cook, J. P., Karthikeyan, S., Lahrouchi, N., Liu, C., Sepulveda, N., Richardson, T. G., Kraja, A., Amouyel, P., Farrall, M., Poulter, N. R., Laakso, M., Zeggini, E., Sever, P., Scott, R. A., Langenberg, C., Wareham, N. J., Conen, D., Palmer, C., Attia, J., Chasman, D. I., Ridker, P. M., Melander, O., Mook-Kanamori, D., van der Harst, P., Cucca, F., Schlessinger, D., Hayward, C., Spector, T. D., Jarvelin, M., Hennig, B. J., Timpson, N. J., Wei, W., Smith, J. C., Xu, Y., Matheny, M. E., Siew, E. E., Lindgren, C., Herzig, K., Dedoussis, G., Denny, J. C., Psaty, B. M., Howson, J. M., Munroe, P. B., Newton-Cheh, C., Caulfield, M. J., Elliott, P., Gaziano, J., Concato, J., Wilson, P. F., Tsao, P. S., Edwards, D., Susztak, K., O'Donnell, C. J., Hung, A. M., Edwards, T. L., Understanding Soc Sci Grp, Int Consortium Blood Pressure, Blood Pressure-Int Consortium, Million Vet Program 2019; 51 (1): 51-+
  • Genome-wide association study of alcohol consumption and use disorder in 274,424 individuals from multiple populations. Nature communications Kranzler, H. R., Zhou, H., Kember, R. L., Vickers Smith, R., Justice, A. C., Damrauer, S., Tsao, P. S., Klarin, D., Baras, A., Reid, J., Overton, J., Rader, D. J., Cheng, Z., Tate, J. P., Becker, W. C., Concato, J., Xu, K., Polimanti, R., Zhao, H., Gelernter, J. 2019; 10 (1): 1499

    Abstract

    Alcohol consumption level and alcohol use disorder (AUD) diagnosis are moderately heritable traits. We conduct genome-wide association studies of these traits using longitudinal Alcohol Use Disorder Identification Test-Consumption (AUDIT-C) scores and AUD diagnoses in a multi-ancestry Million Veteran Program sample (N=274,424). We identify 18 genome-wide significant loci: 5 associated with both traits, 8 associated with AUDIT-C only, and 5 associated with AUD diagnosis only. Polygenic Risk Scores (PRS) for both traits are associated with alcohol-related disorders in two independent samples. Although a significant genetic correlation reflects the overlap between the traits, genetic correlations for 188 non-alcohol-related traits differ significantly for the two traits, as do the phenotypes associated with the traits' PRS. Cell type group partitioning heritability enrichment analyses also differentiate the two traits. We conclude that, although heavy drinking is a key risk factor for AUD, it is not a sufficient cause of the disorder.

    View details for PubMedID 30940813

  • Trans-ethnic association study of blood pressure determinants in over 750,000 individuals. Nature genetics Giri, A., Hellwege, J. N., Keaton, J. M., Park, J., Qiu, C., Warren, H. R., Torstenson, E. S., Kovesdy, C. P., Sun, Y. V., Wilson, O. D., Robinson-Cohen, C., Roumie, C. L., Chung, C. P., Birdwell, K. A., Damrauer, S. M., DuVall, S. L., Klarin, D., Cho, K., Wang, Y., Evangelou, E., Cabrera, C. P., Wain, L. V., Shrestha, R., Mautz, B. S., Akwo, E. A., Sargurupremraj, M., Debette, S., Boehnke, M., Scott, L. J., Luan, J., Zhao, J., Willems, S. M., Theriault, S., Shah, N., Oldmeadow, C., Almgren, P., Li-Gao, R., Verweij, N., Boutin, T. S., Mangino, M., Ntalla, I., Feofanova, E., Surendran, P., Cook, J. P., Karthikeyan, S., Lahrouchi, N., Liu, C., Sepulveda, N., Richardson, T. G., Kraja, A., Amouyel, P., Farrall, M., Poulter, N. R., Understanding Society Scientific Group, International Consortium for Blood Pressure, Blood Pressure-International Consortium of Exome Chip Studies, Laakso, M., Zeggini, E., Sever, P., Scott, R. A., Langenberg, C., Wareham, N. J., Conen, D., Palmer, C. N., Attia, J., Chasman, D. I., Ridker, P. M., Melander, O., Mook-Kanamori, D. O., Harst, P. v., Cucca, F., Schlessinger, D., Hayward, C., Spector, T. D., Jarvelin, M., Hennig, B. J., Timpson, N. J., Wei, W., Smith, J. C., Xu, Y., Matheny, M. E., Siew, E. E., Lindgren, C., Herzig, K., Dedoussis, G., Denny, J. C., Psaty, B. M., Howson, J. M., Munroe, P. B., Newton-Cheh, C., Caulfield, M. J., Elliott, P., Gaziano, J. M., Concato, J., Wilson, P. W., Tsao, P. S., Velez Edwards, D. R., Susztak, K., Million Veteran Program, O'Donnell, C. J., Hung, A. M., Edwards, T. L. 2019; 51 (1): 51–62

    Abstract

    In this trans-ethnic multi-omic study, we reinterpret the genetic architecture of blood pressure to identify genes, tissues, phenomes and medication contexts of blood pressure homeostasis. We discovered 208 novel common blood pressure SNPs and 53 rare variants in genome-wide association studies of systolic, diastolic and pulse pressure in up to 776,078 participants from the Million Veteran Program (MVP) and collaborating studies, with analysis of the blood pressure clinical phenome in MVP. Our transcriptome-wide association study detected 4,043 blood pressure associations with genetically predicted gene expression of 840 genes in 45 tissues, and mouse renal single-cell RNA sequencing identified upregulated blood pressure genes in kidney tubule cells.

    View details for PubMedID 30578418

  • Therapeutic perspective on vascular cognitive impairment. Pharmacological research Toyama, K. n., Spin, J. M., Mogi, M. n., Tsao, P. S. 2019: 104266

    Abstract

    Dementia is one of the greatest public health concerns for the modern aging world. Over the last decade, most researchers developing new therapeutic strategies for dementia have focused on amyloid-β. In contrast, numerous recent studies have indicated that vascular risk factors are associated with various forms of dementia, and that in fact most forms of dementia can be considered an extension of vascular disease. Accordingly, it is sensible to pursue treatment approaches that focus on the blood vessels. Blood-brain barrier (BBB) disruptions in the white matter of patients with vascular cognitive impairment (VCI) have been observed using imaging analysis, and might be potential targets for novel VCI treatment. Tight junctions between cerebral endothelial cells play an important role in the function of the BBB, and recent studies have demonstrated the essential role of microRNAs in regulating tight junctions. Further elucidation of the mechanisms of tight junction-disruption in dementia are likely to lead to promising novel treatments. In this article, we summarize current knowledge regarding microRNAs and vascular cognitive impairment and the possibility of utilizing microRNAs as biomarkers for BBB dysfunction, and seek to envision future therapeutic strategies.

    View details for DOI 10.1016/j.phrs.2019.104266

    View details for PubMedID 31108183

  • Effects of Genetic Variants Associated with Familial Hypercholesterolemia on Low-Density Lipoprotein-Cholesterol Levels and Cardiovascular Outcomes in the Million Veteran Program. Circulation. Genomic and precision medicine Sun, Y. V., Damrauer, S. M., Hui, Q., Assimes, T. L., Ho, Y. L., Natarajan, P., Klarin, D., Huang, J., Lynch, J., DuVall, S. L., Pyarajan, S., Honerlaw, J. P., Gaziano, J. M., Cho, K., Rader, D. J., O'Donnell, C. J., Tsao, P. S., Wilson, P. W. 2018; 11 (12)

    Abstract

    Familial hypercholesterolemia (FH) is characterized by inherited high levels of low-density lipoprotein cholesterol (LDL-C) and premature coronary heart disease (CHD). Over a thousand low-frequency variants in LDLR, APOB and PCSK9 have been implicated in FH but few have been examined at the population level. We aim to estimate the phenotypic effects of a subset of FH variants on LDL-C and clinical outcomes among 331,107 multi-ethnic participants.We examined the individual and collective association between putatively pathogenic FH variants included on the MVP biobank array and the maximum LDL-C level over an interval of 15 years (maxLDL). We assessed the collective effect on clinical outcomes by leveraging data from 61.7 million clinical encounters.We found 8 out of 16 putatively pathogenic FH variants with ≥30 observed carriers to be significantly associated with elevated maxLDL (9.4-80.2 mg/dL). Phenotypic effects were similar for European and African Americans despite substantial differences in carrier frequencies. Based on observed effects on maxLDL, we identified a total of 748 carriers (1:443) who had elevated maxLDL (36.5±1.4 mg/dL, p=1.2×10-152), and higher prevalence of clinical diagnoses related to hypercholesterolemia and CHD in a phenome-wide scan. Adjusted for maxLDL, FH variants collectively associated with higher prevalence of CHD (odds ratio, 1.59 [95% CI 1.36-1.86], p=1.1×10-8) but not peripheral artery disease.The distribution and phenotypic effects of putatively pathogenic FH variants were heterogeneous within and across variants. More robust evidence of genotype-phenotype associations of FH variants in multi-ethnic populations is needed to accurately infer at-risk individuals from genetic screening.

    View details for DOI 10.1161/CIRCGEN.118.002192

    View details for PubMedID 31106297

    View details for PubMedCentralID PMC6516478

  • Genetic analysis of over 1 million people identifies 535 new loci associated with blood pressure traits (vol 50, pg 1412, 2018) NATURE GENETICS Evangelou, E., Warren, H. R., Mosen-Ansorena, D., Mifsud, B., Pazoki, R., Gao, H., Ntritsos, G., Dimou, N., Cabrera, C. P., Karaman, I., Fu Liang Ng, Evangelou, M., Witkowska, K., Tzanis, E., Hellwege, J. N., Giri, A., Edwards, D., Sun, Y. V., Cho, K., Gaziano, J., Wilson, P. F., Tsao, P. S., Kovesdy, C. P., Esko, T., Magi, R., Milani, L., Almgren, P., Boutin, T., Debette, S., Ding, J., Giulianini, F., Holliday, E. G., Jackson, A. U., Li-Gao, R., Lin, W., Luan, J., Mangino, M., Oldmeadow, C., Prins, B., Qian, Y., Sargurupremraj, M., Shah, N., Surendran, P., Theriault, S., Verweij, N., Willems, S. M., Zhao, J., Amouyel, P., Connell, J., de Mutsert, R., Doney, A. F., Farrall, M., Menni, C., Morris, A. D., Noordam, R., Pare, G., Poulter, N. R., Shields, D. C., Stanton, A., Thom, S., Abecasis, G., Amin, N., Arking, D. E., Ayers, K. L., Barbieri, C. M., Batini, C., Bis, J. C., Blake, T., Bochud, M., Boehnke, M., Boerwinkle, E., Boomsma, D. I., Bottinger, E. P., Braund, P. S., Brumat, M., Campbell, A., Campbell, H., Chakravarti, A., Chambers, J. C., Chauhan, G., Ciullo, M., Cocca, M., Collins, F., Cordell, H. J., Davies, G., de Borst, M. H., de Geus, E. J., Deary, I. J., Deelen, J., Del Greco, F. M., Demirkale, C., Dorr, M., Ehret, G. B., Elosua, R., Enroth, S., Erzurumluoglu, A., Ferreira, T., Franberg, M., Franco, O. H., Gandin, I., Gasparini, P., Giedraitis, V., Gieger, C., Girotto, G., Goel, A., Gow, A. J., Gudnason, V., Guo, X., Gyllensten, U., Hamsten, A., Harris, T. B., Harris, S. E., Hartman, C. A., Havulinna, A. S., Hicks, A. A., Hofer, E., Hofman, A., Hottenga, J., Huffman, J. E., Hwang, S., Ingelsson, E., James, A., Jansen, R., Jarvelin, M., Joehanes, R., Johansson, A., Johnson, A. D., Joshi, P. K., Jousilahti, P., Jukema, J., Jula, A., Kahonen, M., Kathiresan, S., Keavney, B. D., Khaw, K., Knekt, P., Knight, J., Kolcic, I., Kooner, J. S., Koskinen, S., Kristiansson, K., Kutalik, Z., Laan, M., Larson, M., Launer, L. J., Lehne, B., Lehtimaki, T., Liewald, D. M., Lin, L., Lind, L., Lindgren, C. M., Liu, Y., Loos, R. F., Lopez, L. M., Lu, Y., Lyytikainen, L., Mahajan, A., Mamasoula, C., Marrugat, J., Marten, J., Milaneschi, Y., Morgan, A., Morris, A. P., Morrison, A. C., Munson, P. J., Nalls, M. A., Nandakumar, P., Nelson, C. P., Niiranen, T., Nolte, I. M., Nutile, T., Oldehinkel, A. J., Oostra, B. A., O'Reilly, P. F., Org, E., Padmanabhan, S., Palmas, W., Palotie, A., Pattie, A., Penninx, B. H., Perola, M., Peters, A., Polasek, O., Pramstaller, P. P., Quang Tri Nguyen, Raitakari, O. T., Ren, M., Rettig, R., Rice, K., Ridker, P. M., Ried, J. S., Riese, H., Ripatti, S., Robino, A., Rose, L. M., Rotter, J. I., Rudan, I., Ruggiero, D., Saba, Y., Sala, C. F., Salomaa, V., Samani, N. J., Sarin, A., Schmidt, R., Schmidt, H., Shrine, N., Siscovick, D., Smith, A. V., Snieder, H., Sober, S., Sorice, R., Starr, J. M., Stott, D. J., Strachan, D. P., Strawbridge, R. J., Sundstrom, J., Swertz, M. A., Taylor, K. D., Teumer, A., Tobin, M. D., Tomaszewski, M., Toniolo, D., Traglia, M., Trompet, S., Tuomilehto, J., Tzourio, C., Uitterlinden, A. G., Vaez, A., van der Most, P. J., van Duijn, C. M., Vergnaud, A., Verwoert, G. C., Vitart, V., Volker, U., Vollenweider, P., Vuckovic, D., Watkins, H., Wild, S. H., Willemsen, G., Wilson, J. F., Wright, A. F., Yao, J., Zemunik, T., Zhang, W., Attia, J. R., Butterworth, A. S., Chasman, D. I., Conen, D., Cucca, F., Danesh, J., Hayward, C., Howson, J. M., Laakso, M., Lakatta, E. G., Langenberg, C., Melander, O., Mook-Kanamori, D. O., Palmer, C. A., Risch, L., Scott, R. A., Scott, R. J., Sever, P., Spector, T. D., van der Harst, P., Wareham, N. J., Zeggini, E., Levy, D., Munroe, P. B., Newton-Cheh, C., Brown, M. J., Metspalu, A., Hung, A. M., O'Donnell, C. J., Edwards, T. L., Psaty, B. M., Tzoulaki, I., Barnes, M. R., Wain, L. V., Elliott, P., Caulfield, M. J., Million Vet Program 2018; 50 (12): 1755
  • Effects of Genetic Variants Associated with Familial Hypercholesterolemia on Low-Density Lipoprotein-Cholesterol Levels and Cardiovascular Outcomes in the Million Veteran Program CIRCULATION-GENOMIC AND PRECISION MEDICINE Sun, Y., Damrauer, S. M., Hui, Q., Assimes, T. L., Ho, Y., Natarajan, P., Klarin, D., Huang, J., Lynch, J., Duvall, S. L., Pyarajan, S., Honerlaw, J. P., Gaziano, J., Cho, K., Rader, D. J., O'Donnell, C. J., Tsao, P. S., Wilson, P. F., VA Million Vet Program 2018; 11 (12)
  • An Automated Algorithm to Quantify Collagen Distribution in Aortic Wall. The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society Nguyen, D. M., Wagenhauser, M. U., Mehrkens, D., Adam, M., Tsao, P. S., Ramasubramanian, A. K. 2018: 22155418814231

    Abstract

    Arterial diseases including abdominal aortic aneurysm and atherosclerosis are biomechanical diseases characterized by significant changes in the structure and strength of the vessel wall. It is now established that local variations in fibrillar collagen and elastin matrix turnover is critical to arterial stiffening and progression of the disease. The collagen content in the aortic wall has nominally been quantified by biochemical assays and immunohistochemical analysis as the total amount because of the difficulty in separating the media and adventitia. In this work, we have developed an algorithm for automatic quantification of layer-specific collagen content from bright-field and polarized microscopic images of histological sections of mouse aorta stained with Picrosirius red (PSR) stain. The images were processed sequentially including separation of layers, erosion, segregation of regions, binarization, and quantification of pixel intensities to obtain collagen content in the media and adventitia separately. We observed that the automated algorithm rapidly and accurately quantified collagen content from a wide range of image quality compared with manual measurements particularly when the medial and adventitial layers overlap. Together, our algorithm will be of significant impact in the rapid, reliable, and accurate analyses of collagen distribution in histological sections of connective tissues.

    View details for PubMedID 30452870

  • Publisher Correction: Genetic analysis of over 1 million people identifies 535 new loci associated with blood pressure traits. Nature genetics Evangelou, E., Warren, H. R., Mosen-Ansorena, D., Mifsud, B., Pazoki, R., Gao, H., Ntritsos, G., Dimou, N., Cabrera, C. P., Karaman, I., Ng, F. L., Evangelou, M., Witkowska, K., Tzanis, E., Hellwege, J. N., Giri, A., Velez Edwards, D. R., Sun, Y. V., Cho, K., Gaziano, J. M., Wilson, P. W., Tsao, P. S., Kovesdy, C. P., Esko, T., Magi, R., Milani, L., Almgren, P., Boutin, T., Debette, S., Ding, J., Giulianini, F., Holliday, E. G., Jackson, A. U., Li-Gao, R., Lin, W., Luan, J., Mangino, M., Oldmeadow, C., Prins, B. P., Qian, Y., Sargurupremraj, M., Shah, N., Surendran, P., Theriault, S., Verweij, N., Willems, S. M., Zhao, J., Amouyel, P., Connell, J., de Mutsert, R., Doney, A. S., Farrall, M., Menni, C., Morris, A. D., Noordam, R., Pare, G., Poulter, N. R., Shields, D. C., Stanton, A., Thom, S., Abecasis, G., Amin, N., Arking, D. E., Ayers, K. L., Barbieri, C. M., Batini, C., Bis, J. C., Blake, T., Bochud, M., Boehnke, M., Boerwinkle, E., Boomsma, D. I., Bottinger, E. P., Braund, P. S., Brumat, M., Campbell, A., Campbell, H., Chakravarti, A., Chambers, J. C., Chauhan, G., Ciullo, M., Cocca, M., Collins, F., Cordell, H. J., Davies, G., de Borst, M. H., de Geus, E. J., Deary, I. J., Deelen, J., Del Greco M, F., Demirkale, C. Y., Dorr, M., Ehret, G. B., Elosua, R., Enroth, S., Erzurumluoglu, A. M., Ferreira, T., Franberg, M., Franco, O. H., Gandin, I., Gasparini, P., Giedraitis, V., Gieger, C., Girotto, G., Goel, A., Gow, A. J., Gudnason, V., Guo, X., Gyllensten, U., Hamsten, A., Harris, T. B., Harris, S. E., Hartman, C. A., Havulinna, A. S., Hicks, A. A., Hofer, E., Hofman, A., Hottenga, J., Huffman, J. E., Hwang, S., Ingelsson, E., James, A., Jansen, R., Jarvelin, M., Joehanes, R., Johansson, A., Johnson, A. D., Joshi, P. K., Jousilahti, P., Jukema, J. W., Jula, A., Kahonen, M., Kathiresan, S., Keavney, B. D., Khaw, K., Knekt, P., Knight, J., Kolcic, I., Kooner, J. S., Koskinen, S., Kristiansson, K., Kutalik, Z., Laan, M., Larson, M., Launer, L. J., Lehne, B., Lehtimaki, T., Liewald, D. C., Lin, L., Lind, L., Lindgren, C. M., Liu, Y., Loos, R. J., Lopez, L. M., Lu, Y., Lyytikainen, L., Mahajan, A., Mamasoula, C., Marrugat, J., Marten, J., Milaneschi, Y., Morgan, A., Morris, A. P., Morrison, A. C., Munson, P. J., Nalls, M. A., Nandakumar, P., Nelson, C. P., Niiranen, T., Nolte, I. M., Nutile, T., Oldehinkel, A. J., Oostra, B. A., O'Reilly, P. F., Org, E., Padmanabhan, S., Palmas, W., Palotie, A., Pattie, A., Penninx, B. W., Perola, M., Peters, A., Polasek, O., Pramstaller, P. P., Nguyen, Q. T., Raitakari, O. T., Ren, M., Rettig, R., Rice, K., Ridker, P. M., Ried, J. S., Riese, H., Ripatti, S., Robino, A., Rose, L. M., Rotter, J. I., Rudan, I., Ruggiero, D., Saba, Y., Sala, C. F., Salomaa, V., Samani, N. J., Sarin, A., Schmidt, R., Schmidt, H., Shrine, N., Siscovick, D., Smith, A. V., Snieder, H., Sober, S., Sorice, R., Starr, J. M., Stott, D. J., Strachan, D. P., Strawbridge, R. J., Sundstrom, J., Swertz, M. A., Taylor, K. D., Teumer, A., Tobin, M. D., Tomaszewski, M., Toniolo, D., Traglia, M., Trompet, S., Tuomilehto, J., Tzourio, C., Uitterlinden, A. G., Vaez, A., van der Most, P. J., van Duijn, C. M., Vergnaud, A., Verwoert, G. C., Vitart, V., Volker, U., Vollenweider, P., Vuckovic, D., Watkins, H., Wild, S. H., Willemsen, G., Wilson, J. F., Wright, A. F., Yao, J., Zemunik, T., Zhang, W., Attia, J. R., Butterworth, A. S., Chasman, D. I., Conen, D., Cucca, F., Danesh, J., Hayward, C., Howson, J. M., Laakso, M., Lakatta, E. G., Langenberg, C., Melander, O., Mook-Kanamori, D. O., Palmer, C. N., Risch, L., Scott, R. A., Scott, R. J., Sever, P., Spector, T. D., van der Harst, P., Wareham, N. J., Zeggini, E., Levy, D., Munroe, P. B., Newton-Cheh, C., Brown, M. J., Metspalu, A., Hung, A. M., O'Donnell, C. J., Edwards, T. L., Million Veteran Program, Psaty, B. M., Tzoulaki, I., Barnes, M. R., Wain, L. V., Elliott, P., Caulfield, M. J. 2018

    Abstract

    In the version of this article originally published, the name of author Martin H. de Borst was coded incorrectly in the XML. The error has now been corrected in the HTML version of the paper.

    View details for PubMedID 30429575

  • Genetics of blood lipids among similar to 300,000 multi-ethnic participants of the Million Veteran Program NATURE GENETICS Klarin, D., Damrauer, S. M., Cho, K., Sun, Y., Teslovich, T. M., Honerlaw, J., Gagnon, D. R., Du Vall, S. L., Li, J., Peloso, G. M., Chaffin, M., Small, A. M., Huang, J., Tang, H., Lynch, J. A., Ho, Y., Liu, D., Emdin, C. A., Li, A. H., Huffman, J. E., Lee, J. S., Natarajan, P., Chowdhury, R., Saleheen, D., Vujkovic, M., Baras, A., Pyarajan, S., Di Angelantonio, E., Neale, B. M., Naheed, A., Khera, A., Danesh, J., Chan, K., Abecasis, G., Willer, C., Dewey, F. E., Carey, D. J., Concato, J., Gaziano, J., O'Donnell, C., Tsao, P. S., Kathiresan, S., Rader, D. J., Wilson, P. F., Assimes, T. L., Global Lipids Genetics Consortium, Myocardial Infarction Genetics MIG, Geisinger-Regeneron DiscovEHR Coll, VA Million Vet Program 2018; 50 (11): 1514-+
  • Chronic Nicotine Exposure Induces Murine Aortic Remodeling and Stiffness Segmentation-Implications for Abdominal Aortic Aneurysm Susceptibility. Frontiers in physiology Wagenhäuser, M. U., Schellinger, I. N., Yoshino, T., Toyama, K., Kayama, Y., Deng, A., Guenther, S. P., Petzold, A., Mulorz, J., Mulorz, P., Hasenfuß, G., Ibing, W., Elvers, M., Schuster, A., Ramasubramanian, A. K., Adam, M., Schelzig, H., Spin, J. M., Raaz, U., Tsao, P. S. 2018; 9: 1459

    Abstract

    Aim: Arterial stiffness is a significant risk factor for many cardiovascular diseases, including abdominal aortic aneurysms (AAA). Nicotine, the major active ingredient of e-cigarettes and tobacco smoke, induces acute vasomotor effects that may temporarily increase arterial stiffness. Here, we investigated the effects of long-term nicotine exposure on structural aortic stiffness. Methods: Mice (C57BL/6) were infused with nicotine for 40 days (20 mg/kg/day). Arterial stiffness of the thoracic (TS) and abdominal (AS) aortic segments was analyzed using ultrasound (PWV, pulse wave velocity) and ex vivo pressure myograph measurements. For mechanistic studies, aortic matrix-metalloproteinase (MMP) expression and activity as well as medial elastin architecture were analyzed. Results: Global aortic stiffness increased with nicotine. In particular, local stiffening of the abdominal segment occurred after 10 days, while thoracic aortic stiffness was only increased after 40 days, resulting in aortic stiffness segmentation. Mechanistically, nicotine exposure enhanced expression of MMP-2/-9 and elastolytic activity in both aortic segments. Elastin degradation occurred in both segments; however, basal elastin levels were higher in the thoracic aorta. Finally, MMP-inhibition significantly reduced nicotine-induced MMP activity, elastin destruction, and aortic stiffening. Conclusion: Chronic nicotine exposure induces aortic MMP expression and structural aortic damage (elastin fragmentation), irreversibly increasing aortic stiffness. This process predominantly affects the abdominal aortic segment, presumably due in part to a lower basal elastin content. This novel phenomenon may help to explain the role of nicotine as a major risk factor for AAA formation and has health implications for ECIGs and other modes of nicotine delivery.

    View details for DOI 10.3389/fphys.2018.01459

    View details for PubMedID 30429794

    View details for PubMedCentralID PMC6220086

  • Chronic Nicotine Exposure Induces Murine Aortic Remodeling and Stiffness Segmentation-Implications for Abdominal Aortic Aneurysm Susceptibility FRONTIERS IN PHYSIOLOGY Wagenhaeuser, M. U., Schellinger, I. N., Yoshino, T., Toyamau, K., Kayamau, Y., Deng, A., Guentheru, S. P., Petzold, A., Mulorz, J., Mulorz, P., Hasenfuss, G., Ibing, W., Elvers, M., Schuster, A., Ramasubramanian, A. K., Adam, M., Schelzig, H., Spin, J. M., Raaz, U., Tsao, P. S. 2018; 9
  • Genetic analysis of over 1 million people identifies 535 new loci associated with blood pressure traits NATURE GENETICS Evangelou, E., Warren, H. R., Mosen-Ansorena, D., Mifsu, B., Pazoki, R., Gao, H., Ntritsos, G., Dimou, N., Cabrer, C. P., Karaman, I., Ng, F., Evangelou, M., Witkowska, K., Tzanis, E., Hellwege, J. N., Giri, A., Edwards, D., Sun, Y., Cho, K., Gaziano, J., Wilson, P. F., Tsao, P. S., Kovesdy, C. P., Esko, T., Magi, R., Milani, L., Almgren, P., Boutin, T., Debette, S., Ding, J., Giulianini, F., Holliday, E. G., Jackson, A. U., Li-Gao, R., Lin, W., Luan, J., Mangino, M., Oldmeadow, C., Prins, B., Qian, Y., Sargurupremraj, M., Shah, N., Surendran, P., Theriault, S., Verweij, N., Willems, S. M., Zhao, J., Amouyel, P., Connell, J., de Mutsert, R., Doney, A. F., Farrall, M., Menni, C., Morris, A. D., Noordam, R., Pare, G., Poulter, N. R., Shields, D. C., Stanton, A., Thom, S., Abecasis, G., Amin, N., Arking, D. E., Ayers, K. L., Barbieri, C. M., Batini, C., Bis, J. C., Blake, T., Bochud, M., Boehnke, M., Boerwinkle, E., Boomsma, D., Bottinger, E. P., Braund, P. S., Brumat, M., Campbell, A., Campbell, H., Chakravarti, A., Chambers, J. C., Chauhan, G., Ciullo, M., Cocca, M., Collins, F., Cordell, H. J., Davies, G., de Borst, M. H., de Geus, E. J., Deary, I. J., Deelen, J., Del Greco, F. M., Demirkale, C., Doerr, M., Ehret, G. B., Elosua, R., Enroth, S., Erzurumluoglu, A., Ferreira, T., Franberg, M., Franco, O. H., Gandin, I., Gasparini, P., Giedraitis, V., Gieger, C., Girotto, G., Goel, A., Gow, A. J., Gudnason, V., Guo, X., Gyllensten, U., Hamsten, A., Harris, T. B., Harris, S. E., Hartman, C. A., Havulinna, A. S., Hicks, A. A., Hofer, E., Hofman, A., Hottenga, J., Huffman, J. E., Hwang, S., Ingelsson, E., James, A., Jansen, R., Jarvelin, M., Joehanes, R., Johansson, A., Johnson, A. D., Joshi, P. K., Jousilahti, P., Jukema, J., Jula, A., Kahonen, M., Kathiresan, S., Keavney, B. D., Khaw, K., Knekt, P., Knight, J., Kolcic, I., Kooner, J. S., Koskinen, S., Kristiansson, K., Kutalik, Z., Laan, M., Larson, M., Launer, L. J., Lehne, B., Lehtimaki, T., Liewald, D. M., Lin, L., Lind, L., Lindgren, C. M., Liu, Y., Loos, R. F., Lopez, L. M., Lu, Y., Lyytikainen, L., Mahajan, A., Mamasoula, C., Marrugat, J., Marten, J., Milaneschi, Y., Morgan, A., Morris, A. P., Morrison, A. C., Munson, P. J., Nalls, M. A., Nandakumar, P., Nelson, C. P., Niiranen, T., Nolte, I. M., Nutile, T., Oldehinkel, A. J., Oostra, B. A., O'Reilly, P. F., Org, E., Padmanabhan, S., Palmas, W., Palotie, A., Pattie, A., Penninx, B. H., Perola, M., Peters, A., Polasek, O., Pramstaller, P. P., Nguyen, Q., Raitakari, O. T., Ren, M., Rettig, R., Rice, K., Ridker, P. M., Ried, J. S., Riese, H., Ripatti, S., Robino, A., Rose, L. M., Rotter, J., Rudan, I., Ruggiero, D., Saba, Y., Sala, C. F., Salomaa, V., Samani, N. J., Sarin, A., Schmidt, R., Schmidt, H., Shrine, N., Siscovick, D., Smith, A., Snieder, H., Sober, S., Sorice, R., Starr, J. M., Stott, D. J., Strachan, D. P., Strawbridge, R. J., Sundstrom, J., Swertz, M. A., Taylor, K. D., Teumer, A., Tobin, M. D., Tomaszewski, M., Toniolo, D., Traglia, M., Trompet, S., Tuomilehto, J., Tzourio, C., Uitterlinden, A. G., Vaez, A., van der Most, P. J., van Duijn, C. M., Vergnaud, A., Verwoert, G. C., Vitart, V., Voelker, U., Vollenweider, P., Vuckovic, D., Watkins, H., Wild, S. H., Willemsen, G., Wilson, J. F., Wright, A. F., Yao, J., Zemunik, T., Zhang, W., Attia, J. R., Butterworth, A. S., Chasman, D., Conen, D., Cucca, F., Danesh, J., Hayward, C., Howson, J. M., Laakso, M., Lakatta, E. G., Langenberg, C., Melander, O., Mook-Kanamori, D. O., Palmer, C. A., Risch, L., Scott, R. A., Scott, R. J., Sever, P., Spector, T. D., van der Harst, P., Wareham, N. J., Zeggini, E., Levy, D., Munroe, P. B., Newton-Cheh, C., Brown, M. J., Metspalu, A., Hung, A. M., O'Donnell, C., Edwards, T. L., Psaty, B. M., Tzoulaki, I., Barnes, M. R., Wain, L., Elliott, P., Caulfield, M. J., Million Vet Program 2018; 50 (10): 1412-+

    Abstract

    High blood pressure is a highly heritable and modifiable risk factor for cardiovascular disease. We report the largest genetic association study of blood pressure traits (systolic, diastolic and pulse pressure) to date in over 1 million people of European ancestry. We identify 535 novel blood pressure loci that not only offer new biological insights into blood pressure regulation but also highlight shared genetic architecture between blood pressure and lifestyle exposures. Our findings identify new biological pathways for blood pressure regulation with potential for improved cardiovascular disease prevention in the future.

    View details for PubMedID 30224653

  • Genetics of blood lipids among ~300,000 multi-ethnic participants of the Million Veteran Program. Nature genetics Klarin, D., Damrauer, S. M., Cho, K., Sun, Y. V., Teslovich, T. M., Honerlaw, J., Gagnon, D. R., DuVall, S. L., Li, J., Peloso, G. M., Chaffin, M., Small, A. M., Huang, J., Tang, H., Lynch, J. A., Ho, Y., Liu, D. J., Emdin, C. A., Li, A. H., Huffman, J. E., Lee, J. S., Natarajan, P., Chowdhury, R., Saleheen, D., Vujkovic, M., Baras, A., Pyarajan, S., Di Angelantonio, E., Neale, B. M., Naheed, A., Khera, A. V., Danesh, J., Chang, K., Abecasis, G., Willer, C., Dewey, F. E., Carey, D. J., Global Lipids Genetics Consortium, Myocardial Infarction Genetics (MIGen) Consortium, Geisinger-Regeneron DiscovEHR Collaboration, VA Million Veteran Program, Concato, J., Gaziano, J. M., O'Donnell, C. J., Tsao, P. S., Kathiresan, S., Rader, D. J., Wilson, P. W., Assimes, T. L. 2018

    Abstract

    The Million Veteran Program (MVP) was established in 2011 as a national research initiative to determine how genetic variation influences the health of US military veterans. Here we genotyped 312,571 MVP participants using a custom biobank array and linked the genetic data to laboratory and clinical phenotypes extracted from electronic health records covering a median of 10.0 years of follow-up. Among 297,626 veterans with at least one blood lipid measurement, including 57,332 black and 24,743 Hispanic participants, we tested up to around 32 million variants for association with lipid levels and identified 118 novel genome-wide significant loci after meta-analysis with data from the Global Lipids Genetics Consortium (total n>600,000). Through a focus on mutations predicted to result in a loss of gene function and a phenome-wide association study, we propose novel indications for pharmaceutical inhibitors targeting PCSK9 (abdominal aortic aneurysm), ANGPTL4 (type 2 diabetes) and PDE3B (triglycerides and coronary disease).

    View details for PubMedID 30275531

  • Validation of Established Genetic Loci for Non-Alcoholic Fatty Liver Disease (NAFLD) and Their Contribution to NAFLD Phenotype in 194,457 Individuals Enrolled in the Million Veteran Program Serper, M., Vujkovic, M., Kaplan, D. E., Carr, R. M., Lee, K., Shao, Q., Miller, D., Huang, J., Reaven, P. D., Phillips, L. S., O'Donnell, C. J., Meigs, J. B., Wilson, P. F., Smith, R., Kranzler, H. R., Justice, A. C., Gaziano, J., Concato, J., Muralidhar, S., Cho, K., Assimes, T. L., Lee, J. S., Tsao, P., Damrauer, S. M., Rader, D. J., Lynch, J., Saleheen, D., Chang, K., DuVall, S. L., VA Million Veteran Program WILEY. 2018: 210A–211A
  • Decoding the Genomics of Abdominal Aortic Aneurysm CELL Li, J., Pan, C., Zhang, S., Spin, J. M., Deng, A., Leung, L. K., Dalman, R. L., Tsao, P. S., Snyder, M. 2018; 174 (6): 1361-+
  • Association of Interleukin 6 Receptor Variant With Cardiovascular Disease Effects of Interleukin 6 Receptor Blocking Therapy A Phenome-Wide Association Study JAMA CARDIOLOGY Cai, T., Zhang, Y., Ho, Y., Link, N., Sun, J., Huang, J., Cai, T. A., Damrauer, S., Ahuja, Y., Honerlaw, J., Costa, L., Schubert, P., Hong, C., Gagnon, D., Sun, Y., Gaziano, J., Wilson, P., Cho, K., Tsao, P., O'Donnell, C. J., Liao, K. P., VA Million Vet Program 2018; 3 (9): 849–57

    Abstract

    Electronic health record (EHR) biobanks containing clinical and genomic data on large numbers of individuals have great potential to inform drug discovery. Individuals with interleukin 6 receptor (IL6R) single-nucleotide polymorphisms (SNPs) who are not receiving IL6R blocking therapy have biomarker profiles similar to those treated with IL6R blockers. This gene-drug pair provides an example to test whether associations of IL6R SNPs with a broad range of phenotypes can inform which diseases may benefit from treatment with IL6R blockade.To determine whether screening for clinical associations with the IL6R SNP in a phenome-wide association study (PheWAS) using EHR biobank data can identify drug effects from IL6R clinical trials.Diagnosis codes and routine laboratory measurements were extracted from the VA Million Veteran Program (MVP); diagnosis codes were mapped to phenotype groups using published PheWAS methods. A PheWAS was performed by fitting logistic regression models for testing associations of the IL6R SNPs with 1342 phenotype groups and by fitting linear regression models for testing associations of the IL6R SNP with 26 routine laboratory measurements. Significance was reported using a false discovery rate of 0.05 or less. Findings were replicated in 2 independent cohorts using UK Biobank and Vanderbilt University Biobank data. The Million Veteran Program included 332 799 US veterans; the UK Biobank, 408 455 individuals from the general population of the United Kingdom; and the Vanderbilt University Biobank, 13 835 patients from a tertiary care center.IL6R SNPs (rs2228145; rs4129267).Phenotypes defined by International Classification of Diseases, Ninth Revision codes.Of the 332 799 veterans included in the main cohort, 305 228 (91.7%) were men, and the mean (SD) age was 66.1 (13.6) years. The IL6R SNP was most strongly associated with a reduced risk of aortic aneurysm phenotypes (odds ratio, 0.87-0.90; 95% CI, 0.84-0.93) in the MVP. We observed known off-target effects of IL6R blockade from clinical trials (eg, higher hemoglobin level). The reduced risk for aortic aneurysms among those with the IL6R SNP in the MVP was replicated in the Vanderbilt University Biobank, and the reduced risk for coronary heart disease was replicated in the UK Biobank.In this proof-of-concept study, we demonstrated application of the PheWAS using large EHR biobanks to inform drug effects. The findings of an association of the IL6R SNP with reduced risk for aortic aneurysms correspond with the newest indication for IL6R blockade, giant cell arteritis, of which a major complication is aortic aneurysm.

    View details for PubMedID 30090940

  • Phenome Wide Association Study of IL6R Variant Identifies Drug Target for Cardiovascular Disease and Inflammation Cai, T., Zhang, Y., Ho, Y., Link, N., Sun, J., Huang, J., Cai, T., Damrauer, S., Ahuja, Y., Honerlaw, J., Huang, J., Costa, L., Schubert, P., Hong, C., Gagnon, D., Sun, Y., Gaziano, M., Wilson, P., Cho, K., Tsao, P., O'Donnell, C. J., Liao, K. P. WILEY. 2018
  • Apelin and APJ orchestrate complex tissue-specific control of cardiomyocyte hypertrophy and contractility in the hypertrophy-heart failure transition AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY Parikh, V. N., Liu, J., Shang, C., Woods, C., Chang, A. C., Zhao, M., Charo, D. N., Grunwald, Z., Huang, Y., Seo, K., Tsao, P. S., Bernstein, D., Ruiz-Lozano, P., Quertermous, T., Ashley, E. A. 2018; 315 (2): H348–H356
  • Systemic Upregulation of IL-10 (Interleukin-10) Using a Nonimmunogenic Vector Reduces Growth and Rate of Dissecting Abdominal Aortic Aneurysm ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Adam, M., Kooreman, N., Jagger, A., Wagenhaeuser, M. U., Mehrkens, D., Wang, Y., Kayama, Y., Toyama, K., Raaz, U., Schellinger, I. N., Maegdefessel, L., Spin, J. M., Hamming, J. F., Quax, P. A., Baldus, S., Wu, J. C., Tsao, P. S. 2018; 38 (8): 1796-1805
  • Non-coding RNAs in aneurysmal aortopathy. Vascular pharmacology Spin, J. M., Li, D. Y., Maegdefessel, L., Tsao, P. S. 2018

    Abstract

    Aortic aneurysms represent a major public health burden, and currently have no medical treatment options. The pathophysiology behind these aneurysms is complex and variable, depending on location and underlying cause, and generally involves progressive dysfunction of all elements of the aortic wall. Changes in smooth muscle behavior, endothelial signaling, extracellular matrix remodeling, and to a variable extent inflammatory signaling and cells, all contribute to the dilation of the aorta, ultimately resulting in high mortality and morbidity events including dissection and rupture. A large number of researchers have identified non-coding RNAs as crucial regulators of aortic aneurysm development, both in humans and in animal models. While most work to-date has focused on microRNAs, intriguing information has also begun to emerge regarding the role of long-non-coding RNAs. This review summarizes the currently available data regarding the involvement of non-coding RNAs in aneurysmal aortopathies. Going forward, these represent key potential therapeutic targets that might be leveraged in the future to slow or prevent aortic aneurysm formation, progression and rupture.

    View details for PubMedID 29909014

  • MicroRNA-Mediated Therapy Modulating Blood-Brain Barrier Disruption Improves Vascular Cognitive Impairment ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Toyama, K., Spin, J. M., Deng, A. C., Huang, T., Wei, K., Wagenhaeuser, M. U., Yoshino, T., Huy Nguyen, Mulorz, J., Kundu, S., Raaz, U., Adam, M., Schellinger, I. N., Jagger, A., Tsao, P. S. 2018; 38 (6): 1392–1406
  • Apelin and APJ orchestrate complex tissue-specific control of cardiomyocyte hypertrophy and contractility in the hypertrophy-heart failure transition. American journal of physiology. Heart and circulatory physiology Parikh, V. N., Liu, J., Shang, C., Woods, C., Chang, A. C., Zhao, M., Charo, D. N., Grunwald, Z., Huang, Y., Seo, K., Tsao, P. S., Bernstein, D., Ruiz-Lozano, P., Quertermous, T., Ashley, E. A. 2018

    Abstract

    The G protein coupled receptor APJ is a promising therapeutic target for heart failure. Constitutive deletion of APJ in the mouse is protective against the hypertrophy-heart failure transition via elimination of ligand-independent, beta-arrestin dependent stretch transduction. However, the cellular origin of this stretch transduction and the details of its interaction with apelin signaling remain unknown. We generated mice with conditional elimination of APJ in the endothelium (APJendo-/-) and myocardium (APJmyo-/-). No baseline difference was observed in LV function in APJendo-/-, APJmyo-/- or controls (APJendo+/+, APJmyo+/+). After exposure to transaortic constriction (TAC), APJendo-/- animals developed left ventricular failure while APJmyo-/- were protected. At the cellular level, carbon fiber stretch of freshly isolated single cardiomyocytes demonstrated decreased contractile response to stretch in APJ-/- cardiomyocytes compared to APJ+/+ cardiomyocytes. Calcium transient did not change with stretch in either APJ-/- or APJ+/+ cardiomyocytes. Application of apelin to APJ+/+ cardiomyocytes resulted in decreased calcium transient. Further, hearts of mice treated with apelin exhibited decreased phosphorylation at Troponin I (cTnI) N-terminal residues (Ser 22,23), consistent with increased calcium sensitivity. These data establish that APJ stretch transduction is mediated specifically by myocardial APJ, that APJ is necessary for stretch-induced increases in contractility, and that apelin opposes APJ's stretch-mediated hypertrophy signaling by lowering calcium transient while maintaining contractility through myofilament calcium sensitization. These findings underscore apelin's unique potential as a therapeutic agent that can simultaneously support cardiac function and protect against the hypertrophy-heart failure transition.

    View details for PubMedID 29775410

  • MicroRNA-Mediated Therapy Modulating Blood-Brain Barrier Disruption Improves Vascular Cognitive Impairment. Arteriosclerosis, thrombosis, and vascular biology Toyama, K., Spin, J. M., Deng, A. C., Huang, T., Wei, K., Wagenhauser, M. U., Yoshino, T., Nguyen, H., Mulorz, J., Kundu, S., Raaz, U., Adam, M., Schellinger, I. N., Jagger, A., Tsao, P. S. 2018

    Abstract

    OBJECTIVE: There are currently no effective treatments for the prevention of dementia associated with vascular cognitive impairment. MicroRNAs regulate gene expression at the post-transcriptional level and play key roles in vascular disorders. TNFalpha (tumor necrosis factor-alpha) regulates blood-brain barrier breakdown through modification of cerebral tight junctions. Here, we sought key TNFalpha-responsive microRNAs that might influence blood-brain barrier breakdown via cerebral tight junction disruption in vascular cognitive impairment.APPROACH AND RESULTS: Using a mouse model of vascular cognitive impairment, chronic cerebral hypoperfusion within the white matter was induced with bilateral common carotid artery stenosis (BCAS) surgery. TNFalpha gene expression was increased in white matter post-BCAS surgery, and TNFalpha stimulation decreased claudin-5, ZO-1 (tight-junction protein 1), and occludin gene expression in murine brain endothelial cells. In silico analysis predicted 8 candidate microRNAs as regulators of claudin-5, ZO-1, and occludin gene expression. Of these, only miR-501-3p was upregulated by TNFalpha in vitro and was upregulated in the white matter after BCAS surgery. Further, miR-501-3p directly bound to the 3'-untranslated region of human ZO-1 and downregulated transendothelial electric resistance. In vivo administration of a locked nucleic acid -modified antisense oligonucleotide versus miR-501-3p suppressed BCAS-induced reduction of ZO-1 gene expression and blood-brain barrier disruption within the white matter and significantly ameliorated working memory deficits after BCAS surgery.CONCLUSIONS: We here provide the first evidence that the TNFalpha-miR-501-3p-ZO-1 axis plays an important role in the pathogenesis of cerebral hypoperfusion-induced working memory deficits and white matter lesions, as a result of blood-brain barrier breakdown via tight junction disruption. Therapeutic manipulation of miR-501-3p holds promise for limiting vascular cognitive impairment progression.

    View details for PubMedID 29650692

  • Antioxidants from diet or supplements do not alter inflammatory markers in adults with cardiovascular disease risk. A pilot randomized controlled trial NUTRITION RESEARCH Dewell, A., Tsao, P., Rigdon, J., Gardner, C. D. 2018; 50: 63–72

    Abstract

    Antioxidants have been reported to have anti-inflammatory effects, but there is a lack of research comparing food to supplement antioxidant sources. The aim of this study was to determine if increases in intake of foods naturally rich in antioxidants would lower blood levels of inflammatory markers more than consuming antioxidant supplements among adults with cardiovascular disease risk factors. Eighty-eight generally healthy adults with ≥1 elevated risk factor for cardiovascular disease were randomized in a single-blind (diets)/double-blind (supplements), parallel-group study for 8 weeks. Participants consumed (1) usual diet and placebo pills (n = 29), (2) usual diet and antioxidant supplements (n = 29), or (3) antioxidant-rich foods closely matched to antioxidant content of supplements and placebo (n = 30). Usual diet combined with antioxidant supplements or increased antioxidant-rich food intake was designed to approximately double daily habitual antioxidant intake. Antioxidant pills included carotenoids, mixed tocopherols, vitamin C, and selenium. Fasting blood samples were analyzed for inflammatory marker concentrations of interleukin-6, monocyte chemotactic protein-1, and soluble intercellular adhesion molecule-1. Participants in the intervention groups successfully doubled most antioxidants as verified by diet records and elevated blood concentrations in treatment groups. Baseline levels of inflammatory markers for the entire study group were 110 ± 65 pg/mL for monocyte chemotactic protein-1, 0.9 ± 0.7 pg/mL for interleukin-6, and 217 ± 56 ng/mL for soluble intercellular adhesion molecule-1 (means ± standard deviation) and did not differ by treatment arm. After 8 weeks, there were no significant within-group changes or between-group 8-week change differences in inflammatory marker concentrations. In conclusion, no beneficial effects were detected on the inflammatory markers investigated in response to antioxidants from foods or supplements.

    View details for PubMedID 29540273

  • GWAS of epigenetic aging rates in blood reveals a critical role for TERT NATURE COMMUNICATIONS Lu, A. T., Xue, L., Salfati, E. L., Chen, B. H., Ferrucci, L., Levy, D., Joehanes, R., Murabito, J. M., Kiel, D. P., Tsai, P., Yet, I., Bell, J. T., Mangino, M., Tanaka, T., McRae, A. F., Marioni, R. E., Visscher, P. M., Wray, N. R., Deary, I. J., Levine, M. E., Quach, A., Assimes, T., Tsao, P. S., Absher, D., Stewart, J. D., Li, Y., Reiner, A. P., Hou, L., Baccarelli, A. A., Whitsel, E. A., Aviv, A., Cardona, A., Day, F. R., Wareham, N. J., Perry, J. B., Ong, K. K., Raj, K., Lunetta, K. L., Horvath, S. 2018; 9: 387

    Abstract

    DNA methylation age is an accurate biomarker of chronological age and predicts lifespan, but its underlying molecular mechanisms are unknown. In this genome-wide association study of 9907 individuals, we find gene variants mapping to five loci associated with intrinsic epigenetic age acceleration (IEAA) and gene variants in three loci associated with extrinsic epigenetic age acceleration (EEAA). Mendelian randomization analysis suggests causal influences of menarche and menopause on IEAA and lipoproteins on IEAA and EEAA. Variants associated with longer leukocyte telomere length (LTL) in the telomerase reverse transcriptase gene (TERT) paradoxically confer higher IEAA (P < 2.7 × 10-11). Causal modeling indicates TERT-specific and independent effects on LTL and IEAA. Experimental hTERT-expression in primary human fibroblasts engenders a linear increase in DNA methylation age with cell population doubling number. Together, these findings indicate a critical role for hTERT in regulating the epigenetic clock, in addition to its established role of compensating for cell replication-dependent telomere shortening.

    View details for PubMedID 29374233

  • Systemic Upregulation of IL-10 (Interleukin-10) Using a Nonimmunogenic Vector Reduces Growth and Rate of Dissecting Abdominal Aortic Aneurysm. Arteriosclerosis, thrombosis, and vascular biology Adam, M. n., Kooreman, N. n., Jagger, A. n., Wagenhaeuser, M. U., Mehrkens, D. n., Wang, Y. n., Kayama, Y. n., Toyama, K. n., Raaz, U. n., Schellinger, I. N., Maegdefessel, L. n., Spin, J. M., Hamming, J. F., Quax, P. H., Baldus, S. n., Wu, J. C., Tsao, P. S. 2018

    Abstract

    Recruitment of immunologic competent cells to the vessel wall is a crucial step in formation of abdominal aortic aneurysms (AAA). Innate immunity effectors (eg, macrophages), as well as mediators of adaptive immunity (eg, T cells), orchestrate a local vascular inflammatory response. IL-10 (interleukin-10) is an immune-regulatory cytokine with a crucial role in suppression of inflammatory processes. We hypothesized that an increase in systemic IL-10-levels would mitigate AAA progression.Using a single intravenous injection protocol, we transfected an IL-10 transcribing nonimmunogenic minicircle vector into the Ang II (angiotensin II)-ApoE-/- infusion mouse model of AAA. IL-10 minicircle transfection significantly reduced average aortic diameter measured via ultrasound at day 28 from 166.1±10.8% (control) to 131.0±5.8% (IL-10 transfected). Rates of dissecting AAA were reduced by IL-10 treatment, with an increase in freedom from dissecting AAA from 21.5% to 62.3%. Using flow cytometry of aortic tissue from minicircle IL-10-treated animals, we found a significantly higher percentage of CD4+/CD25+/Foxp3 (forkhead box P3)+ regulatory T cells, with fewer CD8+/Granzyme B+ cytotoxic T cells. Furthermore, isolated aortic macrophages produced less TNF-α (tumor necrosis factor-α), more IL-10, and were more likely to be MRC1 (mannose receptor, C type 1)-positive alternatively activated macrophages. These results concurred with gene expression analysis of LPS-stimulated and Ang II-primed human peripheral blood mononuclear cells.Taken together, we provide an effective gene therapy approach to AAA in mice by enhancing antiinflammatory and dampening proinflammatory pathways through minicircle-induced augmentation of systemic IL-10 expression.

    View details for PubMedID 29880489

  • Baseline Characterization and Annual Trends of Body Mass Index for a Mega-Biobank Cohort of US Veterans 2011-2017. Journal of health research and reviews in developing countries Nguyen, X. T., Quaden, R. M., Song, R. J., Ho, Y. L., Honerlaw, J. n., Whitbourne, S. n., DuVall, S. L., Deen, J. n., Pyarajan, S. n., Moser, J. n., Huang, G. D., Muralidhar, S. n., Concato, J. n., Tsao, P. S., O'Donnell, C. J., Wilson, P. W., Djousse, L. n., Gagnon, D. R., Gaziano, J. M., Cho, K. n. 2018; 5 (2): 98–107

    Abstract

    Million Veteran Program (MVP) is the largest ongoing mega-cohort biobank program in the US with 570,131 enrollees as of May 2017. The primary aim is to describe demographics, military service, and major diseases and comorbidities of the MVP cohort. Our secondary aim is to examine body mass index (BMI), a proxy for general health, among enrollees.The study population consists of Veterans who actively use the Veterans Health Administration in the US. Data evaluated in this paper combine health information from multiple sources to provide the most comprehensive demographic profile and information on height and weight of MVP enrollees. A standardized cleaning algorithm was used to curate the demographic variables for each participant in MVP. For height and weight, we derived a final data point for each participant to evaluate BMI.Multivariable logistic regression was used to compare the differences in BMI categories across enrollment years adjusting for gender, race, and age. P < 0.05 was considered statistically significant. All analyses were conducted using Statistical Analysis System 9.2.The MVP cohort consists of 90.4% of males with an average age of 61.9 years (standard deviation [SD] = 13.9). MVP is the largest multiethnic biobank cohort within the Veteran population with 73.9% White, 19.0% Black, and 6.5% Hispanic. The most common self-reported disease was hypertension (62.6%) for males and depression (47.5%) for females. Mean BMI was 29.7 kg/m2 (SD = 5.8) with 38.2% obese and 42.3% overweight.Our findings suggest that demographic representation in MVP is similar to the Veterans Health Administration population and contrasts with the overall National Health and Nutrition Examination Survey US population. The prevalence of overweight and obese is high among US Veterans, and future studies will examine the role of BMI and disease risk in the Veteran population.

    View details for PubMedID 33117892

    View details for PubMedCentralID PMC7590919

  • H19 Induces Abdominal Aortic Aneurysm Development and Progression. Circulation Li, D. Y., Busch, A. n., Jin, H. n., Chernogubova, E. n., Pelisek, J. n., Karlsson, J. n., Sennblad, B. n., Liu, S. n., Lao, S. n., Hofmann, P. n., Bäcklund, A. n., Eken, S. M., Roy, J. n., Eriksson, P. n., Dacken, B. n., Ramanujam, D. n., Dueck, A. n., Engelhardt, S. n., Boon, R. A., Eckstein, H. H., Spin, J. M., Tsao, P. S., Maegdefessel, L. n. 2018

    Abstract

    Background -Long noncoding RNAs (lncRNAs) have emerged as critical molecular regulators in various biological processes and diseases. Here we sought to identify and functionally characterize lncRNAs as potential mediators in abdominal aortic aneurysm (AAA) development. Methods -We profiled RNA transcript expression in two murine AAA models, Angiotensin II (ANGII) infusion in ApoE-/- mice (n=8) and porcine pancreatic elastase (PPE) instillation in C57BL/6 wildtype mice (n=12). The lncRNA H19 was identified as one of the most highly up-regulated transcripts in both mouse aneurysm models compared to sham-operated controls. This was confirmed by qRT-PCR and in situ hybridization. Results -Experimental knock-down of H19, utilizing site-specific antisense oligonucleotides (LNA-GapmeRs) in vivo, significantly limited aneurysm growth in both models. Upregulated H19 correlated with smooth muscle cell (SMC) content and SMC apoptosis in progressing aneurysms. Importantly, a similar pattern could be observed in human AAA tissue samples, and in a novel preclinical LDLR-/- Yucatan mini-pig aneurysm model. In vitro knock-down of H19 markedly decreased apoptotic rates of cultured human aortic SMCs, while overexpression of H19 had the opposite effect. Notably, H19-dependent apoptosis mechanisms in SMCs appeared to be independent of miR-675, which is embedded in the first exon of the H19 gene. A customized transcription factor array identified hypoxia-inducible factor 1-alpha (HIF1α) as the main downstream effector. Increased SMC apoptosis was associated with cytoplasmic interaction between H19 and HIF1α and sequential p53 stabilization. Additionally, H19 induced transcription of HIF1α via recruiting the transcription factor specificity protein 1 (Sp1) to the promoter region. Conclusions -The lncRNA H19 is a novel regulator of SMC survival in AAA development and progression. Inhibition of H19 expression might serve as a novel molecular therapeutic target for aortic aneurysm disease.

    View details for PubMedID 29669788

  • Exome-wide association study of plasma lipids in > 300,000 individuals NATURE GENETICS Liu, D. J., Peloso, G. M., Yu, H., Butterworth, A. S., Wang, X., Mahajan, A., Saleheen, D., Emdin, C., Alam, D., Alves, A., Amouyel, P., Di Angelantonio, E., Arveiler, D., Assimes, T. L., Auer, P. L., Baber, U., Ballantyne, C. M., Bang, L. E., Benn, M., Bis, J. C., Boehnke, M., Boerwinkle, E., Bork-Jensen, J., Bottinger, E. P., Brandslund, I., Brown, M., Busonero, F., Caulfield, M. J., Chambers, J. C., Chasman, D. I., Chen, Y., Chen, Y., Chowdhury, R., Christensen, C., Chu, A. Y., Connell, J. M., Cucca, F., Cupples, L., Damrauer, S. M., Davies, G., Deary, I. J., Dedoussis, G., Denny, J. C., Dominiczak, A., Dube, M., Ebeling, T., Eiriksdottir, G., Esko, T., Farmaki, A., Feitosa, M. F., Ferrario, M., Ferrieres, J., Ford, I., Fornage, M., Franks, P. W., Frayling, T. M., Frikke-Schmidt, R., Fritsche, L. G., Frossard, P., Fuster, V., Ganesh, S. K., Gao, W., Garcia, M. E., Gieger, C., Giulianini, F., Goodarzi, M. O., Grallert, H., Grarup, N., Groop, L., Grove, M. L., Gudnason, V., Hansen, T., Harris, T. B., Hayward, C., Hirschhorn, J. N., Holmen, O. L., Huffman, J., Huo, Y., Hveem, K., Jabeen, S., Jackson, A. U., Jakobsdottir, J., Jarvelin, M., Jensen, G. B., Jorgensen, M. E., Jukema, J., Justesen, J. M., Kamstrup, P. R., Kanoni, S., Karpe, F., Kee, F., Khera, A. V., Klarin, D., Koistinen, H. A., Kooner, J. S., Kooperberg, C., Kuulasmaa, K., Kuusisto, J., Laakso, M., Lakka, T., Langenberg, C., Langsted, A., Launer, L. J., Lauritzen, T., Liewald, D. M., Lin, L., Linneberg, A., Loos, R. F., Lu, Y., Lu, X., Magi, R., Malarstig, A., Manichaikul, A., Manning, A. K., Mantyselka, P., Marouli, E., Masca, N. D., Maschio, A., Meigs, J. B., Melander, O., Metspalu, A., Morris, A. P., Morrison, A. C., Mulas, A., Mueller-Nurasyid, M., Munroe, P. B., Neville, M. J., Nielsen, J. B., Nielsen, S. F., Nordestgaard, B. G., Ordovas, J. M., Mehran, R., O'Donnell, C. J., Orho-Melander, M., Molony, C. M., Muntendam, P., Padmanabhan, S., Palmer, C. A., Pasko, D., Patel, A. P., Pedersen, O., Perola, M., Peters, A., Pisinger, C., Pistis, G., Polasek, O., Poulter, N., Psaty, B. M., Rader, D. J., Rasheed, A., Rauramaa, R., Reilly, D. F., Reiner, A. P., Renstrom, F., Rich, S. S., Ridker, P. M., Rioux, J. D., Robertson, N. R., Roden, D. M., Rotter, J. I., Rudan, I., Salomaa, V., Samani, N. J., Sanna, S., Sattar, N., Schmidt, E. M., Scott, R. A., Sever, P., Sevilla, R. S., Shaffer, C. M., Sim, X., Sivapalaratnam, S., Small, K. S., Smith, A. V., Smith, B. H., Somayajula, S., Southam, L., Spector, T. D., Speliotes, E. K., Starr, J. M., Stirrups, K. E., Stitziel, N., Strauch, K., Stringham, H. M., Surendran, P., Tada, H., Tall, A. R., Tang, H., Tardif, J., Taylor, K. D., Trompet, S., Tsao, P. S., Tuomilehto, J., Tybjaerg-Hansen, A., van Zuydam, N. R., Varbo, A., Varga, T. V., Virtamo, J., Waldenberger, M., Wang, N., Wareham, N. J., Warren, H. R., Weeke, P. E., Weinstock, J., Wessel, J., Wilson, J. G., Wilson, P. F., Xu, M., Yaghootkar, H., Young, R., Zeggini, E., Zhang, H., Zheng, N. S., Zhang, W., Zhang, Y., Zhou, W., Zhou, Y., Zoledziewska, M., Howson, J. M., Danesh, J., McCarthy, M. I., Cowan, C. A., Abecasis, G., Deloukas, P., Musunuru, K., Willer, C. J., Kathiresan, S., Charge Diabet Working Grp, EPIC-InterAct Consortium, EPIC-CVD Consortium, GOLD Consortium, VA Million Veteran Program 2017; 49 (12): 1758-+

    Abstract

    We screened variants on an exome-focused genotyping array in >300,000 participants (replication in >280,000 participants) and identified 444 independent variants in 250 loci significantly associated with total cholesterol (TC), high-density-lipoprotein cholesterol (HDL-C), low-density-lipoprotein cholesterol (LDL-C), and/or triglycerides (TG). At two loci (JAK2 and A1CF), experimental analysis in mice showed lipid changes consistent with the human data. We also found that: (i) beta-thalassemia trait carriers displayed lower TC and were protected from coronary artery disease (CAD); (ii) excluding the CETP locus, there was not a predictable relationship between plasma HDL-C and risk for age-related macular degeneration; (iii) only some mechanisms of lowering LDL-C appeared to increase risk for type 2 diabetes (T2D); and (iv) TG-lowering alleles involved in hepatic production of TG-rich lipoproteins (TM6SF2 and PNPLA3) tracked with higher liver fat, higher risk for T2D, and lower risk for CAD, whereas TG-lowering alleles involved in peripheral lipolysis (LPL and ANGPTL4) had no effect on liver fat but decreased risks for both T2D and CAD.

    View details for PubMedID 29083408

    View details for PubMedCentralID PMC5709146

  • Cloud-based interactive analytics for terabytes of genomic variants data. Bioinformatics (Oxford, England) Pan, C., McInnes, G., Deflaux, N., Snyder, M., Bingham, J., Datta, S., Tsao, P. S. 2017; 33 (23): 3709-3715

    Abstract

    Large scale genomic sequencing is now widely used to decipher questions in diverse realms such as biological function, human diseases, evolution, ecosystems, and agriculture. With the quantity and diversity these data harbor, a robust and scalable data handling and analysis solution is desired.We present interactive analytics using a cloud-based columnar database built on Dremel to perform information compression, comprehensive quality controls, and biological information retrieval in large volumes of genomic data. We demonstrate such Big Data computing paradigms can provide orders of magnitude faster turnaround for common genomic analyses, transforming long-running batch jobs submitted via a Linux shell into questions that can be asked from a web browser in seconds. Using this method, we assessed a study population of 475 deeply sequenced human genomes for genomic call rate, genotype and allele frequency distribution, variant density across the genome, and pharmacogenomic information.Our analysis framework is implemented in Google Cloud Platform and BigQuery. Codes are available at https://github.com/StanfordBioinformatics/mvp_aaa_codelabs.cuiping@stanford.edu or ptsao@stanford.edu.Supplementary data are available at Bioinformatics online.

    View details for DOI 10.1093/bioinformatics/btx468

    View details for PubMedID 28961771

    View details for PubMedCentralID PMC5860318

  • Phenotype and genotype analysis of metabolic liver disease in half million US Veterans enrolled in the Million Veteran Program (MVP) megabiobank Serper, M., Kaplan, D. E., Lynch, J., Lee, J., Damrauer, S., Miller, D. R., Shao, Q., Lee, K. M., Reaven, P., Huang, J., Wilson, P. W., O'Donnell, C. J., Rader, D. J., Tsao, P., Saleheen, D., Chang, K., VA Million Vet Program WILEY. 2017: 90A–91A
  • Local microRNA Modulation is a Suitable Way to Prevent In-Stent Restenosis and Coronary Allograft Arteriosclerosis Wang, D., Deuse, T., Stubbendorff, M., Chernogubova, E., Erben, R. G., Eken, S. M., Jin, H., Heeger, C., Behnisch, B., Reichenspurner, H., Robbins, R. C., Spin, J. M., Tsao, P. S., Maegdefessel, L., Schrepfer, S. LIPPINCOTT WILLIAMS & WILKINS. 2017: S28
  • A Stent to Prevent: A Translational Approach Towards Small Abdominal Aortic Aneurysm (AAA) Therapy Schellinger, I. N., Spin, J. M., Hasenfuss, G., Tsao, P. S., Raaz, U. LIPPINCOTT WILLIAMS & WILKINS. 2017
  • Genetic Evidence for Overlap in the Pathogenesis of Peripheral Artery Disease and Coronary Artery Disease Klarin, D., Small, A., Huang, J., Lynch, J., Arya, S., Assimes, T. L., Natarajan, P., Saleheen, D., Kathiresan, S., Rader, D. J., Concato, J., Gaziano, J., Cho, K., Sun, Y., Wilson, P. W., Chang, K., O'Donnell, C. J., Tsao, P. S., Damrauer, S. M. LIPPINCOTT WILLIAMS & WILKINS. 2017
  • The Long Non-Coding RNA H19 Regulates Experimental Abdominal Aortic Aneurysm Development and Progression Li, Y., Jin, H., Busch, A., Chernogubova, E., Backlund, A., Olofsson, A., Eken, S., Sun, C., Simon, N., Korzunowicz, G., Eriksson, P., Hultgren, R., Roy, J., Spin, J., Tsao, P., Maegdefessel, L. LIPPINCOTT WILLIAMS & WILKINS. 2017
  • Nicotine Differentially Influences Segmental Aortic Stiffening Wagenhaeuser, M. U., Schellinger, I. N., Guenther, S. P., Yoshino, T., Toyama, K., Kayama, Y., Deng, A., Zoellner, A. M., Raaz, U., Spin, J. M., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2017
  • Hypoxia inducible factor stabilization improves defective ischemia-induced angiogenesis in a rodent model of chronic kidney disease. Kidney international Schellinger, I. N., Cordasic, N., Panesar, J., Buchholz, B., Jacobi, J., Hartner, A., Klanke, B., Jakubiczka-Smorag, J., Burzlaff, N., Heinze, E., Warnecke, C., Raaz, U., Willam, C., Tsao, P. S., Eckardt, K., Amann, K., Hilgers, K. F. 2017; 91 (3): 616-627

    Abstract

    Chronic kidney disease (CKD) is associated with increased risk and worse prognosis of cardiovascular disease, including peripheral artery disease. An impaired angiogenic response to ischemia may contribute to poor outcomes of peripheral artery disease in patients with CKD. Hypoxia inducible factors (HIF) are master regulators of angiogenesis and therefore represent a promising target for therapeutic intervention. To test this we induced hind-limb ischemia in rats with CKD caused by 5/6 nephrectomy and administered two different treatments known to stabilize HIF protein in vivo: carbon monoxide and a pharmacological inhibitor of prolyl hydroxylation 2-(1-chloro-4- hydroxyisoquinoline-3-carboxamido) acetate (ICA). Expression levels of pro-angiogenic HIF target genes (Vegf, Vegf-r1, Vegf-r2, Ho-1) were measured by qRT-PCR. Capillary density was measured by CD31 immunofluorescence staining and HIF expression was evaluated by immunohistochemistry. Capillary density in ischemic skeletal muscle was significantly lower in CKD animals compared to sham controls. Rats with CKD showed significantly lower expression of HIF and all measured pro-angiogenic HIF target genes, including VEGF. Both HIF stabilizing treatments rescued HIF target gene expression in animals with CKD and led to significantly higher ischemia-induced capillary sprouting compared to untreated controls. ICA was effective regardless of whether it was administered before or after induction of ischemia and led to a HIF expression in skeletal muscle. Thus, impaired ischemia-induced angiogenesis in rats with CKD can be improved by HIF stabilization, even if started after onset of ischemia.

    View details for DOI 10.1016/j.kint.2016.09.028

    View details for PubMedID 27927598

  • Epigenetic clock analysis of diet, exercise, education, and lifestyle factors. Aging Quach, A., Levine, M. E., Tanaka, T., Lu, A. T., Chen, B. H., Ferrucci, L., Ritz, B., Bandinelli, S., Neuhouser, M. L., Beasley, J. M., Snetselaar, L., Wallace, R. B., Tsao, P. S., Absher, D., Assimes, T. L., Stewart, J. D., Li, Y., Hou, L., Baccarelli, A. A., Whitsel, E. A., Horvath, S. 2017; 9 (2): 419-446

    Abstract

    Behavioral and lifestyle factors have been shown to relate to a number of health-related outcomes, yet there is a need for studies that examine their relationship to molecular aging rates. Toward this end, we use recent epigenetic biomarkers of age that have previously been shown to predict all-cause mortality, chronic conditions, and age-related functional decline. We analyze cross-sectional data from 4,173 postmenopausal female participants from the Women's Health Initiative, as well as 402 male and female participants from the Italian cohort study, Invecchiare nel Chianti.Extrinsic epigenetic age acceleration (EEAA) exhibits significant associations with fish intake (p=0.02), moderate alcohol consumption (p=0.01), education (p=3x10(-5)), BMI (p=0.01), and blood carotenoid levels (p=1x10(-5))-an indicator of fruit and vegetable consumption, whereas intrinsic epigenetic age acceleration (IEAA) is associated with poultry intake (p=0.03) and BMI (p=0.05). Both EEAA and IEAA were also found to relate to indicators of metabolic syndrome, which appear to mediate their associations with BMI. Metformin-the first-line medication for the treatment of type 2 diabetes-does not delay epigenetic aging in this observational study. Finally, longitudinal data suggests that an increase in BMI is associated with increase in both EEAA and IEAA.Overall, the epigenetic age analysis of blood confirms the conventional wisdom regarding the benefits of eating a high plant diet with lean meats, moderate alcohol consumption, physical activity, and education, as well as the health risks of obesity and metabolic syndrome.

    View details for DOI 10.18632/aging.101168

    View details for PubMedID 28198702

    View details for PubMedCentralID PMC5361673

  • Effect of Pioglitazone on Cardiometabolic Risk in Patients With Obstructive Sleep Apnea. American journal of cardiology Liu, A., Abbasi, F., Kim, S. H., Ariel, D., Lamendola, C., Cardell, J., Xu, S., Patel, S., Tomasso, V., Mojaddidi, H., Grove, K., Tsao, P. S., Kushida, C. A., Reaven, G. M. 2017

    Abstract

    Prevalence of insulin resistance is increased in patients with obstructive sleep apnea (OSA). Because insulin resistance is an independent predictor of cardiovascular disease (CVD), this study was initiated to see if pioglitazone administration would improve insulin sensitivity and thereby decrease risk of CVD in overweight/obese, nondiabetic, insulin-resistant patients with untreated OSA. Patients (n = 30) were administered pioglitazone (45 mg/day) for 8 weeks, and measurements were made before and after intervention of insulin action (insulin-mediated glucose uptake by the insulin suppression test), C-reactive protein, lipid/lipoprotein profile, and gene expression profile of periumbilical subcutaneous fat tissue. Insulin sensitivity increased 31% (p <0.001) among pioglitazone-treated subjects, associated with a decrease in C-reactive protein concentration (p ≤0.001), a decrease in plasma triglyceride, and increase in high-density lipoprotein cholesterol concentrations (p ≤0.001), accompanied by significant changes in apolipoprotein A1 and B concentrations and lipoprotein subclasses known to decrease CVD risk. In addition, subcutaneous adipose tissue gene expression profile showed a 1.6-fold (p <0.01) increase in GLUT4 expression and decreased expression in 5 of 9 inflammatory genes (p <0.05). In conclusion, enhanced insulin sensitivity can significantly decrease multiple cardiometabolic risk factors in patients with untreated OSA, consistent with the view that coexisting insulin resistance plays an important role in the association between OSA and increased risk of CVD.

    View details for DOI 10.1016/j.amjcard.2016.12.034

    View details for PubMedID 28219664

  • A Pilot Study: The Beneficial Effects of Combined Statinexercise Therapy on Cognitive Function in Patients with Coronary Artery Disease and Mild Cognitive Decline INTERNAL MEDICINE Toyama, K., Sugiyama, S., Oka, H., Hamada, M., Iwasaki, Y., Horio, E., Rokutanda, T., Nakamura, S., Spin, J. M., Tsao, P. S., Ogawa, H. 2017; 56 (6): 641-649

    Abstract

    Objective Hypercholesterolemia, a risk factor in cognitive impairment, can be treated with statins. However, cognitive decline associated with "statins" (HMG-CoA reductase inhibitors) is a clinical concern. This pilot study investigated the effects of combining statins and regular exercise on cognitive function in coronary artery disease (CAD) patients with prior mild cognitive decline. Methods We recruited 43 consecutive CAD patients with mild cognitive decline. These patients were treated with a statin and weekly in-hospital aerobic exercise for 5 months. We measured serum lipids, exercise capacity, and cognitive function using the mini mental state examination (MMSE). Results Low-density lipoprotein cholesterol levels were significantly decreased, and maximum exercise capacity (workload) was significantly increased in patients with CAD and mild cognitive decline after treatment compared with before. Combined statin-exercise therapy significantly increased the median (range) MMSE score from 24 (22-25) to 25 (23-27) across the cohort (p<0.01). Changes in body mass index (BMI) were significantly and negatively correlated with changes in the MMSE. After treatment, MMSE scores in the subgroup of patients that showed a decrease in BMI were significantly improved, but not in the BMI-increased subgroup. Furthermore, the patients already on a statin at the beginning of the trial displayed a more significant improvement in MMSE score than statin-naïve patients, implying that exercise might be the beneficial aspect of this intervention as regards cognition. In a multivariate logistic regression analysis adjusted for age >65 years, sex, and presence of diabetes mellitus, a decrease in BMI during statin-exercise therapy was significantly correlated with an increase in the MMSE score (odds ratio: 4.57, 95% confidence interval: 1.05-20.0; p<0.05). Conclusion Statin-exercise therapy may help improve cognitive dysfunction in patients with CAD and pre-existing mild cognitive decline.

    View details for DOI 10.2169/internalmedicine.56.7703

    View details for Web of Science ID 000398893200010

    View details for PubMedID 28321063

  • Cloud-based Interactive Analytics for Terabytes of Genomic Variants Data Bioinformatics Pan, C., McInnes, G., Deflaux, N., Snyder, M. P., Bingham, J., Datta, S., Tsao, P. S. 2017: 3709–15

    Abstract

    Large scale genomic sequencing is now widely used to decipher questions in diverse realms such as biological function, human diseases, evolution, ecosystems, and agriculture. With the quantity and diversity these data harbor, a robust and scalable data handling and analysis solution is desired.We present interactive analytics using a cloud-based columnar database built on Dremel to perform information compression, comprehensive quality controls, and biological information retrieval in large volumes of genomic data. We demonstrate such Big Data computing paradigms can provide orders of magnitude faster turnaround for common genomic analyses, transforming long-running batch jobs submitted via a Linux shell into questions that can be asked from a web browser in seconds. Using this method, we assessed a study population of 475 deeply sequenced human genomes for genomic call rate, genotype and allele frequency distribution, variant density across the genome, and pharmacogenomic information.Our analysis framework is implemented in Google Cloud Platform and BigQuery. Codes are available at https://github.com/StanfordBioinformatics/mvp_aaa_codelabs.cuiping@stanford.edu or ptsao@stanford.edu.Supplementary data are available at Bioinformatics online.

    View details for DOI 10.1093/bioinformatics/btx468

    View details for PubMedCentralID PMC5860318

  • DNA methylation signatures of chronic low-grade inflammation are associated with complex diseases GENOME BIOLOGY Ligthart, S., Marzi, C., Aslibekyan, S., Mendelson, M. M., Conneely, K. N., Tanaka, T., Colicino, E., Waite, L. L., Joehanes, R., Guan, W., Brody, J. A., Elks, C., Marioni, R., Jhun, M. A., Agha, G., Bressler, J., Ward-Caviness, C. K., Chen, B. H., Huan, T., Bakulski, K., Salfati, E. L., Wahl, S., Schramm, K., Sha, J., Hernandez, D. G., Just, A. C., Smith, J. A., Sotoodehnia, N., Pilling, L. C., Pankow, J. S., Tsao, P. S., Liu, C., Zhao, W., Guarrera, S., Michopoulos, V. J., Smith, A. K., Peters, M. J., Melzer, D., Vokonas, P., Fornage, M., Prokisch, H., Bis, J. C., Chu, A. Y., Herder, C., Grallert, H., Yao, C., Shah, S., McRae, A. F., Lin, H., Horvath, S., Fallin, D., Hofman, A., Wareham, N. J., Wiggins, K. L., Feinberg, A. P., Starr, J. M., Visscher, P. M., Murabito, J. M., Kardia, S. L., Absher, D. M., Binder, E. B., Singleton, A. B., Bandinelli, S., Peters, A., Waldenberger, M., Matullo, G., Schwartz, J. D., Demerath, E. W., Uitterlinden, A. G., van Meurs, J. B., Franco, O. H., Chen, Y. I., Levy, D., Turner, S. T., Deary, I. J., Ressler, K. J., Dupuis, J., Ferrucci, L., Ong, K. K., Assimes, T. L., Boerwinkle, E., Koenig, W., Arnett, D. K., Baccarelli, A. A., Benjamin, E. J., Dehghan, A. 2016; 17

    Abstract

    Chronic low-grade inflammation reflects a subclinical immune response implicated in the pathogenesis of complex diseases. Identifying genetic loci where DNA methylation is associated with chronic low-grade inflammation may reveal novel pathways or therapeutic targets for inflammation.We performed a meta-analysis of epigenome-wide association studies (EWAS) of serum C-reactive protein (CRP), which is a sensitive marker of low-grade inflammation, in a large European population (n = 8863) and trans-ethnic replication in African Americans (n = 4111). We found differential methylation at 218 CpG sites to be associated with CRP (P < 1.15 × 10(-7)) in the discovery panel of European ancestry and replicated (P < 2.29 × 10(-4)) 58 CpG sites (45 unique loci) among African Americans. To further characterize the molecular and clinical relevance of the findings, we examined the association with gene expression, genetic sequence variants, and clinical outcomes. DNA methylation at nine (16%) CpG sites was associated with whole blood gene expression in cis (P < 8.47 × 10(-5)), ten (17%) CpG sites were associated with a nearby genetic variant (P < 2.50 × 10(-3)), and 51 (88%) were also associated with at least one related cardiometabolic entity (P < 9.58 × 10(-5)). An additive weighted score of replicated CpG sites accounted for up to 6% inter-individual variation (R2) of age-adjusted and sex-adjusted CRP, independent of known CRP-related genetic variants.We have completed an EWAS of chronic low-grade inflammation and identified many novel genetic loci underlying inflammation that may serve as targets for the development of novel therapeutic interventions for inflammation.

    View details for DOI 10.1186/s13059-016-1119-5

    View details for PubMedID 27955697

  • Transcriptomic Profiling Maps Anatomically Patterned Subpopulations among Single Embryonic Cardiac Cells DEVELOPMENTAL CELL Li, G., Xu, A., Sim, S., Priest, J. R., Tian, X., Khan, T., Quertermous, T., Zhou, B., Tsao, P. S., Quake, S. R., Wu, S. M. 2016; 39 (4): 491-507

    Abstract

    Embryonic gene expression intricately reflects anatomical context, developmental stage, and cell type. To address whether the precise spatial origins of cardiac cells can be deduced solely from their transcriptional profiles, we established a genome-wide expression database from 118, 949, and 1,166 single murine heart cells at embryonic day 8.5 (e8.5), e9.5, and e10.5, respectively. We segregated these cells by type using unsupervised bioinformatics analysis and identified chamber-specific genes. Using a random forest algorithm, we reconstructed the spatial origin of single e9.5 and e10.5 cardiomyocytes with 92.0% ± 3.2% and 91.2% ± 2.8% accuracy, respectively (99.4% ± 1.0% and 99.1% ± 1.1% if a ±1 zone margin is permitted) and predicted the second heart field distribution of Isl-1-lineage descendants. When applied to Nkx2-5(-/-) cardiomyocytes from murine e9.5 hearts, we showed their transcriptional alteration and lack of ventricular phenotype. Our database and zone classification algorithm will enable the discovery of novel mechanisms in early cardiac development and disease.

    View details for DOI 10.1016/j.devcel.2016.10.014

    View details for Web of Science ID 000389162800013

    View details for PubMedID 27840109

  • DNA methylation-based measures of biological age: meta-analysis predicting time to death. Aging Chen, B. H., Marioni, R. E., Colicino, E., Peters, M. J., Ward-Caviness, C. K., Tsai, P., Roetker, N. S., Just, A. C., Demerath, E. W., Guan, W., Bressler, J., Fornage, M., Studenski, S., Vandiver, A. R., Moore, A. Z., Tanaka, T., Kiel, D. P., Liang, L., Vokonas, P., Schwartz, J., Lunetta, K. L., Murabito, J. M., Bandinelli, S., Hernandez, D. G., Melzer, D., Nalls, M., Pilling, L. C., Price, T. R., Singleton, A. B., Gieger, C., Holle, R., Kretschmer, A., Kronenberg, F., Kunze, S., Linseisen, J., Meisinger, C., Rathmann, W., Waldenberger, M., Visscher, P. M., Shah, S., Wray, N. R., McRae, A. F., Franco, O. H., Hofman, A., Uitterlinden, A. G., Absher, D., Assimes, T., Levine, M. E., Lu, A. T., Tsao, P. S., Hou, L., Manson, J. E., Carty, C. L., LaCroix, A. Z., Reiner, A. P., Spector, T. D., Feinberg, A. P., Levy, D., Baccarelli, A., van Meurs, J., Bell, J. T., Peters, A., Deary, I. J., Pankow, J. S., Ferrucci, L., Horvath, S. 2016; 8 (9): 1844-1865

    Abstract

    Estimates of biological age based on DNA methylation patterns, often referred to as "epigenetic age", "DNAm age", have been shown to be robust biomarkers of age in humans. We previously demonstrated that independent of chronological age, epigenetic age assessed in blood predicted all-cause mortality in four human cohorts. Here, we expanded our original observation to 13 different cohorts for a total sample size of 13,089 individuals, including three racial/ethnic groups. In addition, we examined whether incorporating information on blood cell composition into the epigenetic age metrics improves their predictive power for mortality. All considered measures of epigenetic age acceleration were predictive of mortality (p≤8.2x10(-9)), independent of chronological age, even after adjusting for additional risk factors (p<5.4x10(-4)), and within the racial/ethnic groups that we examined (non-Hispanic whites, Hispanics, African Americans). Epigenetic age estimates that incorporated information on blood cell composition led to the smallest p-values for time to death (p=7.5x10(-43)). Overall, this study a) strengthens the evidence that epigenetic age predicts all-cause mortality above and beyond chronological age and traditional risk factors, and b) demonstrates that epigenetic age estimates that incorporate information on blood cell counts lead to highly significant associations with all-cause mortality.

    View details for DOI 10.18632/aging.101020

    View details for PubMedID 27690265

  • Role of microRNAs on Blood Brain Barrier Dysfunction in Vascular Cognitive Impairment. Current drug delivery Toyama, K., Spin, J. M., Tsao, P. S. 2016: -?

    Abstract

    Dementia cases are increasing as the population ages, leading to increased financial costs. Several neuronal diseases including ischemic and hemorrhagic stroke involve cerebrovascular injury or pathophysiology. Cerebrovascular injury is closely tied to blood brain barrier (BBB) disruption. Many studies have shown a significant association between BBB dysfunction and neurological diseases. Therefore, an understanding of the molecular mechanisms which regulate BBB permeability and disruption is essential for establishing future therapeutic strategies to alter dementia disease progression related to cerebrovascular injury,so-called vascular cognitive impairment (VCI). microRNAs (miRs) are small noncodingRNAs that regulate gene expression through targeting of mRNA transcripts.miRs have been implicated in the development and progression of various illnesses, including vascular disease. However, the role of miRs in BBB breakdown or permeability and VCI development has not yet been well clarified.Research content related to the origins of VCI and the role of the BBB in pathologic development and therapeutic targeting are reviewed, including current relevant animal models. We draw from the published literature regarding microRNA candidates that are associated with modulation of BBB structure and function.In this review, we summarize the current knowledge about VCI, explore the potential role of miRs in BBB breakdown and VCI progression, and identify potential candidate miRs for development of new treatment strategies.miRs constitute a promising novel avenue as future therapeutic options for alteration of both BBB permeability and development of VCI.

    View details for PubMedID 27572324

  • Does enhanced insulin sensitivity improve sleep measures in patients with obstructive sleep apnea: a randomized, placebo-controlled pilot study. Sleep medicine Liu, A., Kim, S. H., Ariel, D., Abbasi, F., Lamendola, C., Cardell, J., Xu, S., Patel, S., Tomasso, V., Mojaddidi, H., Grove, K., Tsao, P. S., Kushida, C. A., Reaven, G. M. 2016; 22: 57-60

    Abstract

    High fasting insulin levels have been reported to predict development of observed apneas, suggesting that insulin resistance may contribute to the pathogenesis of obstructive sleep apnea (OSA). The aim of this study was to determine whether enhancing insulin sensitivity in individuals with OSA would improve sleep measures.Insulin-resistant, nondiabetic individuals with untreated OSA were randomized (2:1) to pioglitazone (45 mg/day) or placebo for eight weeks in this single-blind study. All individuals had repeat measurements pertaining to sleep (overnight polysomnography and functional outcomes of sleep questionnaire) and insulin action (insulin suppression test).A total of 45 overweight/obese men and women with moderate/severe OSA were randomized to pioglitazone (n = 30) or placebo (n = 15). Although insulin sensitivity increased 31% among pioglitazone-treated compared with no change among individuals receiving placebo (p <0.001 for between-group difference), no improvement in quantitative or qualitative sleep measurements was observed.Pioglitazone administration increased insulin sensitivity in otherwise untreated individuals with OSA, without any change in polysomnographic sleep measures over an eight-week period. These findings do not support a causal role for insulin resistance in the pathogenesis of OSA.

    View details for DOI 10.1016/j.sleep.2016.06.005

    View details for PubMedID 27544837

  • Response to Letters Regarding Article, "Segmental Aortic Stiffening Contributes to Experimental Abdominal Aortic Aneurysm Development" CIRCULATION Raaz, U., Zoellner, A. M., Schellinger, I. N., Toh, R., Nakagami, F., Brandt, M., Emrich, F. C., Kayama, Y., Eken, S., Adam, M., Maegdefessel, L., Hertel, T., Deng, A., Jagger, A., Buerke, M., Dalman, R. L., Spin, J. M., Kuhl, E., Tsao, P. S. 2016; 133 (1): E11–E12

    View details for PubMedID 26719393

    View details for PubMedCentralID PMC4704124

  • Identification and validation of N-acetyltransferase 2 as an insulin sensitivity gene. journal of clinical investigation Knowles, J. W., Xie, W., Zhang, Z., Chennamsetty, I., Assimes, T. L., Paananen, J., Hansson, O., Pankow, J., Goodarzi, M. O., Carcamo-Orive, I., Morris, A. P., Chen, Y. I., Mäkinen, V., Ganna, A., Mahajan, A., Guo, X., Abbasi, F., Greenawalt, D. M., Lum, P., Molony, C., Lind, L., Lindgren, C., Raffel, L. J., Tsao, P. S., Schadt, E. E., Rotter, J. I., Sinaiko, A., Reaven, G., Yang, X., Hsiung, C. A., Groop, L., Cordell, H. J., Laakso, M., Hao, K., Ingelsson, E., Frayling, T. M., Weedon, M. N., Walker, M., Quertermous, T. 2016; 126 (1): 403-?

    View details for DOI 10.1172/JCI85921

    View details for PubMedID 26727231

    View details for PubMedCentralID PMC4701558

  • Heme Oxygenase-1 Expression Affects Murine Abdominal Aortic Aneurysm Progression. PloS one Azuma, J., Wong, R. J., Morisawa, T., Hsu, M., Maegdefessel, L., Zhao, H., Kalish, F., Kayama, Y., Wallenstein, M. B., Deng, A. C., Spin, J. M., Stevenson, D. K., Dalman, R. L., Tsao, P. S. 2016; 11 (2)

    Abstract

    Heme oxygenase-1 (HO-1), the rate-limiting enzyme in heme degradation, is a cytoprotective enzyme upregulated in the vasculature by increased flow and inflammatory stimuli. Human genetic data suggest that a diminished HO-1 expression may predispose one to abdominal aortic aneurysm (AAA) development. In addition, heme is known to strongly induce HO-1 expression. Utilizing the porcine pancreatic elastase (PPE) model of AAA induction in HO-1 heterozygous (HO-1+/-, HO-1 Het) mice, we found that a deficiency in HO-1 leads to augmented AAA development. Peritoneal macrophages from HO-1+/- mice showed increased gene expression of pro-inflammatory cytokines, including MCP-1, TNF-alpha, IL-1-beta, and IL-6, but decreased expression of anti-inflammatory cytokines IL-10 and TGF-beta. Furthermore, treatment with heme returned AAA progression in HO-1 Het mice to a wild-type profile. Using a second murine AAA model (Ang II-ApoE-/-), we showed that low doses of the HMG-CoA reductase inhibitor rosuvastatin can induce HO-1 expression in aortic tissue and suppress AAA progression in the absence of lipid lowering. Our results support those studies that suggest that pleiotropic statin effects might be beneficial in AAA, possibly through the upregulation of HO-1. Specific targeted therapies designed to induce HO-1 could become an adjunctive therapeutic strategy for the prevention of AAA disease.

    View details for DOI 10.1371/journal.pone.0149288

    View details for PubMedID 26894432

  • An epigenetic clock analysis of race/ethnicity, sex, and coronary heart disease. Genome biology Horvath, S., Gurven, M., Levine, M. E., Trumble, B. C., Kaplan, H., Allayee, H., Ritz, B. R., Chen, B., Lu, A. T., Rickabaugh, T. M., Jamieson, B. D., Sun, D., Li, S., Chen, W., Quintana-Murci, L., Fagny, M., Kobor, M. S., Tsao, P. S., Reiner, A. P., Edlefsen, K. L., Absher, D., Assimes, T. L. 2016; 17 (1): 171-?

    Abstract

    Epigenetic biomarkers of aging (the "epigenetic clock") have the potential to address puzzling findings surrounding mortality rates and incidence of cardio-metabolic disease such as: (1) women consistently exhibiting lower mortality than men despite having higher levels of morbidity; (2) racial/ethnic groups having different mortality rates even after adjusting for socioeconomic differences; (3) the black/white mortality cross-over effect in late adulthood; and (4) Hispanics in the United States having a longer life expectancy than Caucasians despite having a higher burden of traditional cardio-metabolic risk factors.We analyzed blood, saliva, and brain samples from seven different racial/ethnic groups. We assessed the intrinsic epigenetic age acceleration of blood (independent of blood cell counts) and the extrinsic epigenetic aging rates of blood (dependent on blood cell counts and tracks the age of the immune system). In blood, Hispanics and Tsimane Amerindians have lower intrinsic but higher extrinsic epigenetic aging rates than Caucasians. African-Americans have lower extrinsic epigenetic aging rates than Caucasians and Hispanics but no differences were found for the intrinsic measure. Men have higher epigenetic aging rates than women in blood, saliva, and brain tissue.Epigenetic aging rates are significantly associated with sex, race/ethnicity, and to a lesser extent with CHD risk factors, but not with incident CHD outcomes. These results may help elucidate lower than expected mortality rates observed in Hispanics, older African-Americans, and women.

    View details for DOI 10.1186/s13059-016-1030-0

    View details for PubMedID 27511193

  • Dietary fructose in pregnancy induces hyperglycemia, hypertension, and pathologic kidney and liver changes in a rodent model PREGNANCY HYPERTENSION-AN INTERNATIONAL JOURNAL OF WOMENS CARDIOVASCULAR HEALTH Shortliffe, L. M., Hammam, O., Han, X., Kouba, E., Tsao, P. S., Wang, B. 2015; 5 (4): 308-314

    Abstract

    The incidence of pregnancies complicated by hyperglycemia and hypertension is increasing along with associated morbidities to mother and offspring. The high fructose diet is a well-studied model that induces hyperglycemia and hypertension in male rodents, but may not affect females. We hypothesized that the physiologic stress of pregnancy may alter metabolic responses to dietary fructose.In this study female Sprague-Dawley rats were divided into two gestational dietary groups: (1) 60% carbohydrate standard rat chow (Pregnant-S-controls) and (2) 60% fructose enriched chow (Pregnant-F). Body weight, blood pressure, blood glucose, triglycerides, and insulin were measured in pregnancy and during the post-partum period. Maternal organ weight and histological changes were also assessed after delivery.By midpregnancy Pregnant-F rats had increased weight, elevated blood pressure, higher fasting glucose, and elevated triglycerides compared with Pregnant-S rats. Both groups demonstrated elevated gestational insulin levels with signs of insulin resistance (increased HOMA-IR). Pregnant-F rats showed significant histopathologic hepatic steatosis and renal tubular changes characterized by tubular dilation and glomerulosclerosis.Our study provides a model in which dietary change during pregnancy can be examined. We demonstrate, moreover, that high dietary fructose ingestion in pregnant rats may result in profound systemic and pathologic changes not appreciated during routine pregnancy.

    View details for DOI 10.1016/j.preghy.2015.08.002

    View details for Web of Science ID 000366078600010

    View details for PubMedID 26597746

  • Diabetic Cardiovascular Disease Induced by Oxidative Stress INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Kayama, Y., Raaz, U., Jagger, A., Adam, M., Schellinger, I. N., Sakamoto, M., Suzuki, H., Toyama, K., Spin, J. M., Tsao, P. S. 2015; 16 (10): 25234-25263

    Abstract

    Cardiovascular disease (CVD) is the leading cause of morbidity and mortality among patients with diabetes mellitus (DM). DM can lead to multiple cardiovascular complications, including coronary artery disease (CAD), cardiac hypertrophy, and heart failure (HF). HF represents one of the most common causes of death in patients with DM and results from DM-induced CAD and diabetic cardiomyopathy. Oxidative stress is closely associated with the pathogenesis of DM and results from overproduction of reactive oxygen species (ROS). ROS overproduction is associated with hyperglycemia and metabolic disorders, such as impaired antioxidant function in conjunction with impaired antioxidant activity. Long-term exposure to oxidative stress in DM induces chronic inflammation and fibrosis in a range of tissues, leading to formation and progression of disease states in these tissues. Indeed, markers for oxidative stress are overexpressed in patients with DM, suggesting that increased ROS may be primarily responsible for the development of diabetic complications. Therefore, an understanding of the pathophysiological mechanisms mediated by oxidative stress is crucial to the prevention and treatment of diabetes-induced CVD. The current review focuses on the relationship between diabetes-induced CVD and oxidative stress, while highlighting the latest insights into this relationship from findings on diabetic heart and vascular disease.

    View details for DOI 10.3390/ijms161025234

    View details for PubMedID 26512646

  • Human Engineered Heart Muscles Engraft and Survive Long Term in a Rodent Myocardial Infarction Model. Circulation research Riegler, J., Tiburcy, M., Ebert, A., Tzatzalos, E., Raaz, U., Abilez, O. J., Shen, Q., Kooreman, N. G., Neofytou, E., Chen, V. C., Wang, M., Meyer, T., Tsao, P. S., Connolly, A. J., Couture, L. A., Gold, J. D., Zimmermann, W. H., Wu, J. C. 2015; 117 (8): 720-730

    Abstract

    Tissue engineering approaches may improve survival and functional benefits from human embryonic stem cell-derived cardiomyocyte transplantation, thereby potentially preventing dilative remodeling and progression to heart failure.Assessment of transport stability, long-term survival, structural organization, functional benefits, and teratoma risk of engineered heart muscle (EHM) in a chronic myocardial infarction model.We constructed EHMs from human embryonic stem cell-derived cardiomyocytes and released them for transatlantic shipping following predefined quality control criteria. Two days of shipment did not lead to adverse effects on cell viability or contractile performance of EHMs (n=3, P=0.83, P=0.87). One month after ischemia/reperfusion injury, EHMs were implanted onto immunocompromised rat hearts to simulate chronic ischemia. Bioluminescence imaging showed stable engraftment with no significant cell loss between week 2 and 12 (n=6, P=0.67), preserving ≤25% of the transplanted cells. Despite high engraftment rates and attenuated disease progression (change in ejection fraction for EHMs, -6.7±1.4% versus control, -10.9±1.5%; n>12; P=0.05), we observed no difference between EHMs containing viable and nonviable human cardiomyocytes in this chronic xenotransplantation model (n>12; P=0.41). Grafted cardiomyocytes showed enhanced sarcomere alignment and increased connexin 43 expression at 220 days after transplantation. No teratomas or tumors were found in any of the animals (n=14) used for long-term monitoring.EHM transplantation led to high engraftment rates, long-term survival, and progressive maturation of human cardiomyocytes. However, cell engraftment was not correlated with functional improvements in this chronic myocardial infarction model. Most importantly, the safety of this approach was demonstrated by the lack of tumor or teratoma formation.

    View details for DOI 10.1161/CIRCRESAHA.115.306985

    View details for PubMedID 26291556

  • Local MicroRNA Modulation Using a Novel Anti-miR21-Eluting Stent Effectively Prevents Experimental In-Stent Restenosis ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Wang, D., Deuse, T., Stubbendorff, M., Chernogubova, E., Erben, R. G., Eken, S. M., Jin, H., Li, Y., Busch, A., Heeger, C., Behnisch, B., Reichenspurner, H., Robbins, R. C., Spin, J. M., Tsao, P. S., Schrepfer, S., Maegdefessel, L. 2015; 35 (9): 1945-1953

    Abstract

    Despite advances in stent technology for vascular interventions, in-stent restenosis (ISR) because of myointimal hyperplasia remains a major complication.We investigated the regulatory role of microRNAs in myointimal hyperplasia/ISR, using a humanized animal model in which balloon-injured human internal mammary arteries with or without stenting were transplanted into Rowett nude rats, followed by microRNA profiling. miR-21 was the only significantly upregulated candidate. In addition, miR-21 expression was increased in human tissue samples from patients with ISR compared with coronary artery disease specimen. We systemically repressed miR-21 via intravenous fluorescein-tagged-locked nucleic acid-anti-miR-21 (anti-21) in our humanized myointimal hyperplasia model. As expected, suppression of vascular miR-21 correlated dose dependently with reduced luminal obliteration. Furthermore, anti-21 did not impede reendothelialization. However, systemic anti-miR-21 had substantial off-target effects, lowering miR-21 expression in liver, heart, lung, and kidney with concomitant increase in serum creatinine levels. We therefore assessed the feasibility of local miR-21 suppression using anti-21-coated stents. Compared with bare-metal stents, anti-21-coated stents effectively reduced ISR, whereas no significant off-target effects could be observed.This study demonstrates the efficacy of an anti-miR-coated stent for the reduction of ISR.

    View details for DOI 10.1161/ATVBAHA.115.305597

    View details for Web of Science ID 000360497600008

    View details for PubMedCentralID PMC4552606

  • Local MicroRNA Modulation Using a Novel Anti-miR-21-Eluting Stent Effectively Prevents Experimental In-Stent Restenosis. Arteriosclerosis, thrombosis, and vascular biology Wang, D., Deuse, T., Stubbendorff, M., Chernogubova, E., Erben, R. G., Eken, S. M., Jin, H., Li, Y., Busch, A., Heeger, C., Behnisch, B., Reichenspurner, H., Robbins, R. C., Spin, J. M., Tsao, P. S., Schrepfer, S., Maegdefessel, L. 2015; 35 (9): 1945-1953

    Abstract

    Despite advances in stent technology for vascular interventions, in-stent restenosis (ISR) because of myointimal hyperplasia remains a major complication.We investigated the regulatory role of microRNAs in myointimal hyperplasia/ISR, using a humanized animal model in which balloon-injured human internal mammary arteries with or without stenting were transplanted into Rowett nude rats, followed by microRNA profiling. miR-21 was the only significantly upregulated candidate. In addition, miR-21 expression was increased in human tissue samples from patients with ISR compared with coronary artery disease specimen. We systemically repressed miR-21 via intravenous fluorescein-tagged-locked nucleic acid-anti-miR-21 (anti-21) in our humanized myointimal hyperplasia model. As expected, suppression of vascular miR-21 correlated dose dependently with reduced luminal obliteration. Furthermore, anti-21 did not impede reendothelialization. However, systemic anti-miR-21 had substantial off-target effects, lowering miR-21 expression in liver, heart, lung, and kidney with concomitant increase in serum creatinine levels. We therefore assessed the feasibility of local miR-21 suppression using anti-21-coated stents. Compared with bare-metal stents, anti-21-coated stents effectively reduced ISR, whereas no significant off-target effects could be observed.This study demonstrates the efficacy of an anti-miR-coated stent for the reduction of ISR.

    View details for DOI 10.1161/ATVBAHA.115.305597

    View details for PubMedID 26183619

    View details for PubMedCentralID PMC4552606

  • Transcription Factor Runx2 Promotes Aortic Fibrosis and Stiffness in Type 2 Diabetes Mellitus CIRCULATION RESEARCH Raaz, U., Schellinger, I. N., Chernogubova, E., Warnecke, C., Kayama, Y., Penov, K., Hennigs, J. K., Salomons, F., Eken, S., Emrich, F. C., Zheng, W. H., Adam, M., Jagger, A., Nakagami, F., Toh, R., Toyama, K., Deng, A., Buerke, M., Maegdefessel, L., Hasenfuss, G., Spin, J. M., Tsao, P. S. 2015; 117 (6): 513-524

    Abstract

    Accelerated arterial stiffening is a major complication of diabetes mellitus with no specific therapy available to date.The present study investigates the role of the osteogenic transcription factor runt-related transcription factor 2 (Runx2) as a potential mediator and therapeutic target of aortic fibrosis and aortic stiffening in diabetes mellitus.Using a murine model of type 2 diabetes mellitus (db/db mice), we identify progressive structural aortic stiffening that precedes the onset of arterial hypertension. At the same time, Runx2 is aberrantly upregulated in the medial layer of db/db aortae, as well as in thoracic aortic samples from patients with type 2 diabetes mellitus. Vascular smooth muscle cell-specific overexpression of Runx2 in transgenic mice increases expression of its target genes, Col1a1 and Col1a2, leading to medial fibrosis and aortic stiffening. Interestingly, increased Runx2 expression per se is not sufficient to induce aortic calcification. Using in vivo and in vitro approaches, we further demonstrate that expression of Runx2 in diabetes mellitus is regulated via a redox-sensitive pathway that involves a direct interaction of NF-κB with the Runx2 promoter.In conclusion, this study highlights Runx2 as a previously unrecognized inducer of vascular fibrosis in the setting of diabetes mellitus, promoting arterial stiffness irrespective of calcification.

    View details for DOI 10.1161/CIRCRESAHA.115.306341

    View details for Web of Science ID 000360142000007

    View details for PubMedCentralID PMC4553105

  • Transcription Factor Runx2 Promotes Aortic Fibrosis and Stiffness in Type 2 Diabetes Mellitus. Circulation research Raaz, U., Schellinger, I. N., Chernogubova, E., Warnecke, C., Kayama, Y., Penov, K., Hennigs, J. K., Salomons, F., Eken, S., Emrich, F. C., Zheng, W. H., Adam, M., Jagger, A., Nakagami, F., Toh, R., Toyama, K., Deng, A., Buerke, M., Maegdefessel, L., Hasenfuß, G., Spin, J. M., Tsao, P. S. 2015; 117 (6): 513-524

    Abstract

    Accelerated arterial stiffening is a major complication of diabetes mellitus with no specific therapy available to date.The present study investigates the role of the osteogenic transcription factor runt-related transcription factor 2 (Runx2) as a potential mediator and therapeutic target of aortic fibrosis and aortic stiffening in diabetes mellitus.Using a murine model of type 2 diabetes mellitus (db/db mice), we identify progressive structural aortic stiffening that precedes the onset of arterial hypertension. At the same time, Runx2 is aberrantly upregulated in the medial layer of db/db aortae, as well as in thoracic aortic samples from patients with type 2 diabetes mellitus. Vascular smooth muscle cell-specific overexpression of Runx2 in transgenic mice increases expression of its target genes, Col1a1 and Col1a2, leading to medial fibrosis and aortic stiffening. Interestingly, increased Runx2 expression per se is not sufficient to induce aortic calcification. Using in vivo and in vitro approaches, we further demonstrate that expression of Runx2 in diabetes mellitus is regulated via a redox-sensitive pathway that involves a direct interaction of NF-κB with the Runx2 promoter.In conclusion, this study highlights Runx2 as a previously unrecognized inducer of vascular fibrosis in the setting of diabetes mellitus, promoting arterial stiffness irrespective of calcification.

    View details for DOI 10.1161/CIRCRESAHA.115.306341

    View details for PubMedID 26208651

  • Levosimendan displays anti-inflammatory effects and decreases MPO bioavailability in patients with severe heart failure SCIENTIFIC REPORTS Adam, M., Meyer, S., Knors, H., Klinke, A., Radunski, U. K., Rudolph, T. K., Rudolph, V., Spin, J. M., Tsao, P. S., Costard-Jaeckle, A., Baldus, S. 2015; 5

    Abstract

    Treatment of decompensated heart failure often includes administration of levosimendan. Myeloperoxidase (MPO) is released during polymorphonuclear neutrophil (PMN) degranulation, and mediates dysregulation of vascular tone in heart failure. We evaluated the effects of levosimendan-treatment on MPO in patients with acute decompensation of chronic heart failure over a one week course. Plasma MPO levels were significantly decreased after levosimendan treatment (from 252.1 ± 31.1 pmol/l at baseline to 215.02 ± 27.96 pmol/l at 6 h, p < 0.05). Ex vivo incubation of whole blood with levosimendan decreased MPO release after PMN-stimulation (8.2 ± 1.4-fold increase at baseline vs. 6.0 ± 1.1-fold increase with levosimendan). MPO levels also significantly correlated with diastolic blood pressure over the time course. In a multivariate linear model, the main contributor to systolic, diastolic and mean blood pressure was level of PMN elastase. MPO contributed only in heparin-treated patients, suggesting a more significant role for endothelial-bound MPO than for circulating MPO or elastase with respect to blood pressure regulation. We here provide the first evidence that levosimendan treatment inhibits MPO release by PMNs in decompensated heart failure patients. This mechanism may regulate endothelial function and vascular tone in heart failure patients.

    View details for DOI 10.1038/srep09704

    View details for Web of Science ID 000352724400001

    View details for PubMedID 25867530

    View details for PubMedCentralID PMC4394753

  • Identification and validation of N-acetyltransferase 2 as an insulin sensitivity gene JOURNAL OF CLINICAL INVESTIGATION Knowles, J. W., Xie, W., Zhang, Z., Chennemsetty, I., Assimes, T. L., Paananen, J., Hansson, O., Pankow, J., Goodarzi, M. O., Carcamo-Orive, I., Morris, A. P., Chen, Y. I., Maekinen, V., Ganna, A., Mahajan, A., Guo, X., Abbasi, F., Greenawalt, D. M., Lum, P., Molony, C., Lind, L., Lindgren, C., Raffel, L. J., Tsao, P. S., Schadt, E. E., Rotter, J. I., Sinaiko, A., Reaven, G., Yang, X., Hsiung, C. A., Groop, L., Cordell, H. J., Laakso, M., Hao, K., Ingelsson, E., Frayling, T. M., Weedon, M. N., Walker, M., Quertermous, T. 2015; 125 (4): 1739-1751

    Abstract

    Decreased insulin sensitivity, also referred to as insulin resistance (IR), is a fundamental abnormality in patients with type 2 diabetes and a risk factor for cardiovascular disease. While IR predisposition is heritable, the genetic basis remains largely unknown. The GENEticS of Insulin Sensitivity consortium conducted a genome-wide association study (GWAS) for direct measures of insulin sensitivity, such as euglycemic clamp or insulin suppression test, in 2,764 European individuals, with replication in an additional 2,860 individuals. The presence of a nonsynonymous variant of N-acetyltransferase 2 (NAT2) [rs1208 (803A>G, K268R)] was strongly associated with decreased insulin sensitivity that was independent of BMI. The rs1208 "A" allele was nominally associated with IR-related traits, including increased fasting glucose, hemoglobin A1C, total and LDL cholesterol, triglycerides, and coronary artery disease. NAT2 acetylates arylamine and hydrazine drugs and carcinogens, but predicted acetylator NAT2 phenotypes were not associated with insulin sensitivity. In a murine adipocyte cell line, silencing of NAT2 ortholog Nat1 decreased insulin-mediated glucose uptake, increased basal and isoproterenol-stimulated lipolysis, and decreased adipocyte differentiation, while Nat1 overexpression produced opposite effects. Nat1-deficient mice had elevations in fasting blood glucose, insulin, and triglycerides and decreased insulin sensitivity, as measured by glucose and insulin tolerance tests, with intermediate effects in Nat1 heterozygote mice. Our results support a role for NAT2 in insulin sensitivity.

    View details for DOI 10.1172/JCI74592

    View details for Web of Science ID 000352248600037

    View details for PubMedID 25798622

  • MicroRNAs in Abdominal Aortic Aneurysm. Current vascular pharmacology Adam, M., Raaz, U., Spin, J. M., Tsao, P. S. 2015; 13 (3): 280-290

    Abstract

    Abdominal aortic aneurysms (AAA) are an important source of morbidity and mortality in the U.S. and worldwide. Treatment options are limited, with open surgery or endovascular repair remaining the only curative treatments. Classical cardiovascular medications have generally failed to prevent or significantly alter AAA formation or progression. Therefore, there is a tremendous need for better therapeutic approaches. With increasing knowledge of microRNA (miR) regulation in the context of cardiovascular disease, and with improving technical options permitting alteration of miR-expression levels in vitro and in vivo, we are offered a glimpse into the diagnostic and therapeutic possibilities of using miRs to treat vascular pathobiology. This review focuses on the role of miRs in aneurysmal disease of the abdominal aorta, summarizing recent publications regarding this topic, and outlining known effects of relevant miRs in AAA formation, including miR-21 and miR-29b. Despite there being only limited studies available, several other miRs also display clear potential for alteration of the disease process including miR-26a, the miR-17-92-cluster, miRs-221/222, miR-133 and miR-146a. While studies have shown that miRs can regulate the activity and interplay of vascular inflammatory cells, endothelial cells, smooth muscle cells and fibroblasts, all key elements leading to AAA formation, much work remains to be done.

    View details for PubMedID 23713862

  • Levosimendan displays anti-inflammatory effects and decreases MPO bioavailability in patients with severe heart failure. Scientific reports Adam, M., Meyer, S., Knors, H., Klinke, A., Radunski, U. K., Rudolph, T. K., Rudolph, V., Spin, J. M., Tsao, P. S., Costard-Jäckle, A., Baldus, S. 2015; 5: 9704-?

    Abstract

    Treatment of decompensated heart failure often includes administration of levosimendan. Myeloperoxidase (MPO) is released during polymorphonuclear neutrophil (PMN) degranulation, and mediates dysregulation of vascular tone in heart failure. We evaluated the effects of levosimendan-treatment on MPO in patients with acute decompensation of chronic heart failure over a one week course. Plasma MPO levels were significantly decreased after levosimendan treatment (from 252.1 ± 31.1 pmol/l at baseline to 215.02 ± 27.96 pmol/l at 6 h, p < 0.05). Ex vivo incubation of whole blood with levosimendan decreased MPO release after PMN-stimulation (8.2 ± 1.4-fold increase at baseline vs. 6.0 ± 1.1-fold increase with levosimendan). MPO levels also significantly correlated with diastolic blood pressure over the time course. In a multivariate linear model, the main contributor to systolic, diastolic and mean blood pressure was level of PMN elastase. MPO contributed only in heparin-treated patients, suggesting a more significant role for endothelial-bound MPO than for circulating MPO or elastase with respect to blood pressure regulation. We here provide the first evidence that levosimendan treatment inhibits MPO release by PMNs in decompensated heart failure patients. This mechanism may regulate endothelial function and vascular tone in heart failure patients.

    View details for DOI 10.1038/srep09704

    View details for PubMedID 25867530

  • Erratum: miR-24 limits aortic vascular inflammation and murine abdominal aneurysm development. Nature communications Maegdefessel, L., Spin, J. M., Raaz, U., Eken, S. M., Toh, R., Azuma, J., Adam, M., Nakagami, F., Heymann, H. M., Chernogubova, E., Jin, H., Roy, J., Hultgren, R., Caidahl, K., Schrepfer, S., Hamsten, A., Eriksson, P., McConnell, M. V., Dalman, R. L., Tsao, P. S. 2015; 6: 6506-?

    View details for DOI 10.1038/ncomms7506

    View details for PubMedID 25716653

  • Battle of the bulge: miR-195 versus miR-29b in aortic aneurysm. Circulation research Spin, J. M., Tsao, P. S. 2014; 115 (10): 812-813

    View details for DOI 10.1161/CIRCRESAHA.114.305233

    View details for PubMedID 25342766

    View details for PubMedCentralID PMC4323148

  • Red blood cells serve as intravascular carriers of myeloperoxidase. Journal of molecular and cellular cardiology Adam, M., Gajdova, S., Kolarova, H., Kubala, L., Lau, D., Geisler, A., Ravekes, T., Rudolph, V., Tsao, P. S., Blankenberg, S., Baldus, S., Klinke, A. 2014; 74: 353-363

    Abstract

    Myeloperoxidase (MPO) is a heme enzyme abundantly expressed in polymorphonuclear neutrophils. MPO is enzymatically capable of catalyzing the generation of reactive oxygen species (ROS) and the consumption of nitric oxide (NO). Thus MPO has both potent microbicidal and, upon binding to the vessel wall, pro-inflammatory properties. Interestingly, MPO - a highly cationic protein - has been shown to bind to both endothelial cells and leukocyte membranes. Given the anionic surface charge of red blood cells, we investigated binding of MPO to erythrocytes. Red blood cells (RBCs) derived from patients with elevated MPO plasma levels showed significantly higher amounts of MPO by flow cytometry and ELISA than healthy controls. Heparin-induced MPO-release from patient-derived RBCs was significantly increased compared to controls. Ex vivo experiments revealed dose and time dependency for MPO-RBC binding, and immunofluorescence staining as well as confocal microscopy localized MPO-RBC interaction to the erythrocyte plasma membrane. NO-consumption by RBC-membrane fragments (erythrocyte "ghosts") increased with incrementally greater concentrations of MPO during incubation, indicating preserved catalytic MPO activity. In vivo infusion of MPO-loaded RBCs into C57BL/6J mice increased local MPO tissue concentrations in liver, spleen, lung, and heart tissue as well as within the cardiac vasculature. Further, NO-dependent relaxation of aortic rings was altered by RBC bound-MPO and systemic vascular resistance significantly increased after infusion of MPO-loaded RBCs into mice. In summary, we find that MPO binds to RBC membranes in vitro and in vivo, is transported by RBCs to remote sites in mice, and affects endothelial function as well as systemic vascular resistance. RBCs may avidly bind circulating MPO, and act as carriers of this leukocyte-derived enzyme.

    View details for DOI 10.1016/j.yjmcc.2014.06.009

    View details for PubMedID 24976018

  • New ways to dismantle a ticking time bomb: microRNA 712/205 and abdominal aortic aneurysm development. Arteriosclerosis, thrombosis, and vascular biology Maegdefessel, L., Spin, J. M., Tsao, P. S. 2014; 34 (7): 1339-1340

    View details for DOI 10.1161/ATVBAHA.114.303952

    View details for PubMedID 24951652

  • Dichloroacetate prevents restenosis in preclinical animal models of vessel injury. Nature Deuse, T., Hua, X., Wang, D., Maegdefessel, L., Heeren, J., Scheja, L., Bolaños, J. P., Rakovic, A., Spin, J. M., Stubbendorff, M., Ikeno, F., Länger, F., Zeller, T., Schulte-Uentrop, L., Stoehr, A., Itagaki, R., Haddad, F., Eschenhagen, T., Blankenberg, S., Kiefmann, R., Reichenspurner, H., Velden, J., Klein, C., Yeung, A., Robbins, R. C., Tsao, P. S., Schrepfer, S. 2014; 509 (7502): 641-644

    Abstract

    Despite the introduction of antiproliferative drug-eluting stents, coronary heart disease remains the leading cause of death in the United States. In-stent restenosis and bypass graft failure are characterized by excessive smooth muscle cell (SMC) proliferation and concomitant myointima formation with luminal obliteration. Here we show that during the development of myointimal hyperplasia in human arteries, SMCs show hyperpolarization of their mitochondrial membrane potential (ΔΨm) and acquire a temporary state with a high proliferative rate and resistance to apoptosis. Pyruvate dehydrogenase kinase isoform 2 (PDK2) was identified as a key regulatory protein, and its activation proved necessary for relevant myointima formation. Pharmacologic PDK2 blockade with dichloroacetate or lentiviral PDK2 knockdown prevented ΔΨm hyperpolarization, facilitated apoptosis and reduced myointima formation in injured human mammary and coronary arteries, rat aortas, rabbit iliac arteries and swine (pig) coronary arteries. In contrast to several commonly used antiproliferative drugs, dichloroacetate did not prevent vessel re-endothelialization. Targeting myointimal ΔΨm and alleviating apoptosis resistance is a novel strategy for the prevention of proliferative vascular diseases.

    View details for DOI 10.1038/nature13232

    View details for PubMedID 24747400

  • Dichloroacetate prevents restenosis in preclinical animal models of vessel injury. Nature Deuse, T., Hua, X., Wang, D., Maegdefessel, L., Heeren, J., Scheja, L., Bolaños, J. P., Rakovic, A., Spin, J. M., Stubbendorff, M., Ikeno, F., Länger, F., Zeller, T., Schulte-Uentrop, L., Stoehr, A., Itagaki, R., Haddad, F., Eschenhagen, T., Blankenberg, S., Kiefmann, R., Reichenspurner, H., Velden, J., Klein, C., Yeung, A., Robbins, R. C., Tsao, P. S., Schrepfer, S. 2014; 509 (7502): 641-644

    Abstract

    Despite the introduction of antiproliferative drug-eluting stents, coronary heart disease remains the leading cause of death in the United States. In-stent restenosis and bypass graft failure are characterized by excessive smooth muscle cell (SMC) proliferation and concomitant myointima formation with luminal obliteration. Here we show that during the development of myointimal hyperplasia in human arteries, SMCs show hyperpolarization of their mitochondrial membrane potential (ΔΨm) and acquire a temporary state with a high proliferative rate and resistance to apoptosis. Pyruvate dehydrogenase kinase isoform 2 (PDK2) was identified as a key regulatory protein, and its activation proved necessary for relevant myointima formation. Pharmacologic PDK2 blockade with dichloroacetate or lentiviral PDK2 knockdown prevented ΔΨm hyperpolarization, facilitated apoptosis and reduced myointima formation in injured human mammary and coronary arteries, rat aortas, rabbit iliac arteries and swine (pig) coronary arteries. In contrast to several commonly used antiproliferative drugs, dichloroacetate did not prevent vessel re-endothelialization. Targeting myointimal ΔΨm and alleviating apoptosis resistance is a novel strategy for the prevention of proliferative vascular diseases.

    View details for DOI 10.1038/nature13232

    View details for PubMedID 24747400

  • Hemodynamic regulation of reactive oxygen species: implications for vascular diseases. Antioxidants & redox signaling Raaz, U., Toh, R., Maegdefessel, L., Adam, M., Nakagami, F., Emrich, F. C., Spin, J. M., Tsao, P. S. 2014; 20 (6): 914-928

    Abstract

    Significance: Arterial blood vessels functionally and structurally adapt to altering hemodynamic forces in order to accommodate changing needs and to provide stress homeostasis. This ability is achieved at the cellular level by converting mechanical stimulation into biochemical signals (i.e., mechanotransduction). Whereas physiological mechanical stress helps to maintain vascular structure and function, pathologic or aberrant stress may impair cellular mechano-signaling, and initiate or augment cellular processes which drive disease. Recent advances: Reactive oxygen species (ROS) may represent an intriguing class of mechanically- regulated second messengers. Chronically enhanced ROS-generation may be induced by adverse mechanical stresses, and is associated with a multitude of vascular diseases. Although a causal relationship has clearly been demonstrated in large numbers of animal studies, an effective ROS-modulating therapy still remains to be established by clinical studies. Critical issues and Future directions: This review article focuses on the role of various mechanical forces (in the form of laminar shear stress, oscillatory shear stress or cyclic stretch) as modulators of ROS- driven signaling, and their subsequent effects on vascular biology and homeostasis, as well as on specific diseases such as arteriosclerosis, hypertension and abdominal aortic aneurysms. Specifically, it highlights the significance of the various NADPH oxidase (NOX) isoforms as critical ROS generators in the vasculature. Directed targeting of defined components in the complex network of ROS (mechano)signaling may represent a key for successful translation of experimental findings into clinical practice.

    View details for DOI 10.1089/ars.2013.5507

    View details for PubMedID 23879326

  • MicroRNA-29b regulation of abdominal aortic aneurysm development TRENDS IN CARDIOVASCULAR MEDICINE Maegdefessel, L., Azuma, J., Tsao, P. S. 2014; 24 (1): 1-6

    Abstract

    Tremendous efforts have been initiated to elucidate the molecular and pathophysiological characteristics of abdominal aortic aneurysm (AAA) disease, which is a significant contributor to morbidity and mortality in the Western world. Recently, a novel class of small noncoding RNAs, called microRNAs, was identified as important transcriptional and posttranscriptional inhibitors of gene expression thought to simultaneously "fine tune" the translational output of multiple target messenger RNAs (mRNAs) by promoting mRNA degradation or inhibiting translation. Several research groups were able to identify the miR-29 family, and miR-29b in particular, as crucial regulators of-not only vascular fibrosis-but also cardiac-, kidney-, liver-, and skin-fibrosis. The current review briefly points out data indicating a causal role for miR-29 in various diseases, while focusing on its potential benefit during AAA initiation and propagation.

    View details for DOI 10.1016/j.tcm.2013.05.002

    View details for Web of Science ID 000329384000001

    View details for PubMedID 23871588

    View details for PubMedCentralID PMC3815986

  • miR-24 limits aortic vascular inflammation and murine abdominal aneurysm development. Nature communications Maegdefessel, L., Spin, J. M., Raaz, U., Eken, S. M., Toh, R., Azuma, J., Adam, M., Nakagami, F., Heymann, H. M., Chernogubova, E., Jin, H., Roy, J., Hultgren, R., Caidahl, K., Schrepfer, S., Hamsten, A., Eriksson, P., McConnell, M. V., Dalman, R. L., Tsao, P. S. 2014; 5: 5214-?

    Abstract

    Identification and treatment of abdominal aortic aneurysm (AAA) remain among the most prominent challenges in vascular medicine. MicroRNAs (miRNAs) are crucial regulators of cardiovascular pathology and represent intriguing targets to limit AAA expansion. Here we show, by using two established murine models of AAA disease along with human aortic tissue and plasma analysis, that miR-24 is a key regulator of vascular inflammation and AAA pathology. In vivo and in vitro studies reveal chitinase 3-like 1 (Chi3l1) to be a major target and effector under the control of miR-24, regulating cytokine synthesis in macrophages as well as their survival, promoting aortic smooth muscle cell migration and cytokine production, and stimulating adhesion molecule expression in vascular endothelial cells. We further show that modulation of miR-24 alters AAA progression in animal models, and that miR-24 and CHI3L1 represent novel plasma biomarkers of AAA disease progression in humans.

    View details for DOI 10.1038/ncomms6214

    View details for PubMedID 25358394

  • MicroRNAs Are Novel Plasma Biomarkers for Diagnosis and Prognosis of Abdominal Aortic Aneurysm Disease Chernogubova, E., Eken, S. M., Spin, J. M., Raaz, U., Jin, H., Roy, J., Hamsten, A., Eriksson, P., Tsao, P. S., Maegdefessel, L. LIPPINCOTT WILLIAMS & WILKINS. 2013
  • Micromanaging Abdominal Aortic Aneurysms INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Maegdefessel, L., Spin, J. M., Adam, M., Raaz, U., Toh, R., Nakagami, F., Tsao, P. S. 2013; 14 (7): 14374-14394

    Abstract

    The contribution of abdominal aortic aneurysm (AAA) disease to human morbidity and mortality has increased in the aging, industrialized world. In response, extraordinary efforts have been launched to determine the molecular and pathophysiological characteristics of the diseased aorta. This work aims to develop novel diagnostic and therapeutic strategies to limit AAA expansion and, ultimately, rupture. Contributions from multiple research groups have uncovered a complex transcriptional and post-transcriptional regulatory milieu, which is believed to be essential for maintaining aortic vascular homeostasis. Recently, novel small noncoding RNAs, called microRNAs, have been identified as important transcriptional and post-transcriptional inhibitors of gene expression. MicroRNAs are thought to "fine tune" the translational output of their target messenger RNAs (mRNAs) by promoting mRNA degradation or inhibiting translation. With the discovery that microRNAs act as powerful regulators in the context of a wide variety of diseases, it is only logical that microRNAs be thoroughly explored as potential therapeutic entities. This current review summarizes interesting findings regarding the intriguing roles and benefits of microRNA expression modulation during AAA initiation and propagation. These studies utilize disease-relevant murine models, as well as human tissue from patients undergoing surgical aortic aneurysm repair. Furthermore, we critically examine future therapeutic strategies with regard to their clinical and translational feasibility.

    View details for DOI 10.3390/ijms140714374

    View details for Web of Science ID 000322171700085

    View details for PubMedID 23852016

  • Measurement of insulin-mediated glucose uptake: direct comparison of the modified insulin suppression test and the euglycemic, hyperinsulinemic clamp. Metabolism Knowles, J. W., Assimes, T. L., Tsao, P. S., Natali, A., Mari, A., Quertermous, T., Reaven, G. M., Abbasi, F. 2013; 62 (4): 548-553

    Abstract

    Two direct measurements of peripheral insulin sensitivity are the M value derived from the euglycemic, hyperinsulinemic clamp (EC) and the steady-state plasma glucose (SSPG) concentration derived from the insulin suppression test (IST). Prior work suggests that these measures are highly correlated, but the agreement between them is unknown. To determine the agreement between SSPG and M and to develop transformation equations to convert SSPG to M and vice versa, we directly compared these two measurements in the same individuals.A total of 15 nondiabetic subjects (9 women and 6 men) underwent both an EC and a modified version of the IST within a median interval of 5days. We performed standard correlation metrics of the two measures and developed transformation regression equations for the two measures.The mean±SD age of the subjects was 57±7years and body mass index, 27.7±3.9kg/m(2). The median (interquartile range) SSPG concentration was 6.7 (5.1, 9.8) mmol/L and M value, 49.6 (28.9, 64.2) μmol/min/kg-LBM. There was a highly significant correlation between SSPG and M (r=-0.87, P <0.001). The relationship was best fit by regression models with exponential/logarithmic functions (R(2)=0.85). Bland-Altman plots demonstrated an excellent agreement between these measures of insulin action.The SSPG and M are highly related measures of insulin sensitivity and the results provide the means to directly compare the two measurements.

    View details for DOI 10.1016/j.metabol.2012.10.002

    View details for PubMedID 23151437

  • MicroRNA-24 controls abdominal aortic aneurysm development through regulation of YKL-40 Maegdefessel, L., Raaz, U., Adam, M., Spin, J., Eriksson, P., Hamsten, A., Tsao, P. SPRINGER. 2013: 10–10
  • Oxidative Stress And Cyclic Strain Mediated Smad6 Regulation In Vascular Endothelial Cells Correlates With Autophagy Induction And Endothelial Dysfunction Hayashi, S., Matsushita, H., Kawano, Y., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2013
  • Loss of CDKN2B promotes p53-dependent smooth muscle cell apoptosis and aneurysm formation. Arteriosclerosis, thrombosis, and vascular biology Leeper, N. J., Raiesdana, A., Kojima, Y., Kundu, R. K., Cheng, H., Maegdefessel, L., Toh, R., Ahn, G., Ali, Z. A., Anderson, D. R., Miller, C. L., Roberts, S. C., Spin, J. M., de Almeida, P. E., Wu, J. C., Xu, B., Cheng, K., Quertermous, M., Kundu, S., Kortekaas, K. E., Berzin, E., Downing, K. P., Dalman, R. L., Tsao, P. S., Schadt, E. E., Owens, G. K., Quertermous, T. 2013; 33 (1): e1-e10

    Abstract

    Genomewide association studies have implicated allelic variation at 9p21.3 in multiple forms of vascular disease, including atherosclerotic coronary heart disease and abdominal aortic aneurysm. As for other genes at 9p21.3, human expression quantitative trait locus studies have associated expression of the tumor suppressor gene CDKN2B with the risk haplotype, but its potential role in vascular pathobiology remains unclear.Here we used vascular injury models and found that Cdkn2b knockout mice displayed the expected increase in proliferation after injury, but developed reduced neointimal lesions and larger aortic aneurysms. In situ and in vitro studies suggested that these effects were attributable to increased smooth muscle cell apoptosis. Adoptive bone marrow transplant studies confirmed that the observed effects of Cdkn2b were mediated through intrinsic vascular cells and were not dependent on bone marrow-derived inflammatory cells. Mechanistic studies suggested that the observed increase in apoptosis was attributable to a reduction in MDM2 and an increase in p53 signaling, possibly due in part to compensation by other genes at the 9p21.3 locus. Dual inhibition of both Cdkn2b and p53 led to a reversal of the vascular phenotype in each model.These results suggest that reduced CDKN2B expression and increased smooth muscle cell apoptosis may be one mechanism underlying the 9p21.3 association with aneurysmal disease.

    View details for DOI 10.1161/ATVBAHA.112.300399

    View details for PubMedID 23162013

  • Loss of CDKN2B Promotes p53-Dependent Smooth Muscle Cell Apoptosis and Aneurysm Formation ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Leeper, N. J., Raiesdana, A., Kojima, Y., Kundu, R. K., Cheng, H., Maegdefessel, L., Toh, R., Ahn, G., Ali, Z. A., Anderson, D. R., Miller, C. L., Roberts, S. C., Spin, J. M., de Almeida, P. E., Wu, J. C., Xu, B., Cheng, K., Quertermous, M., Kundu, S., Kortekaas, K. E., Berzin, E., Downing, K. P., Dalman, R. L., Tsao, P. S., Schadt, E. E., Owens, G. K., Quertermous, T. 2013; 33 (1): E1-?

    Abstract

    Genomewide association studies have implicated allelic variation at 9p21.3 in multiple forms of vascular disease, including atherosclerotic coronary heart disease and abdominal aortic aneurysm. As for other genes at 9p21.3, human expression quantitative trait locus studies have associated expression of the tumor suppressor gene CDKN2B with the risk haplotype, but its potential role in vascular pathobiology remains unclear.Here we used vascular injury models and found that Cdkn2b knockout mice displayed the expected increase in proliferation after injury, but developed reduced neointimal lesions and larger aortic aneurysms. In situ and in vitro studies suggested that these effects were attributable to increased smooth muscle cell apoptosis. Adoptive bone marrow transplant studies confirmed that the observed effects of Cdkn2b were mediated through intrinsic vascular cells and were not dependent on bone marrow-derived inflammatory cells. Mechanistic studies suggested that the observed increase in apoptosis was attributable to a reduction in MDM2 and an increase in p53 signaling, possibly due in part to compensation by other genes at the 9p21.3 locus. Dual inhibition of both Cdkn2b and p53 led to a reversal of the vascular phenotype in each model.These results suggest that reduced CDKN2B expression and increased smooth muscle cell apoptosis may be one mechanism underlying the 9p21.3 association with aneurysmal disease.

    View details for DOI 10.1161/ATVBAHA.112.300399

    View details for Web of Science ID 000312392500001

    View details for PubMedID 23162013

    View details for PubMedCentralID PMC3569043

  • Prospective Transcriptomic Pathway Analysis of Human Lymphatic Vascular Insufficiency: Identification and Validation of a Circulating Biomarker Panel PLOS ONE Lin, S., Kim, J., Lee, M., Roche, L., Yang, N. L., Tsao, P. S., Rockson, S. G. 2012; 7 (12)

    Abstract

    In our previous transcriptional profiling of a murine model, we have identified a remarkably small number of specific pathways with altered expression in lymphedema. In this investigation, we utilized microarray-based transcriptomics of human skin for an unbiased a priori prospective candidate identification, with subsequent validation of these candidates through direct serum assay. The resulting multi-analyte biomarker panel sensitively should sensitively discriminate human lymphedema subjects from normal individuals.We enrolled 63 lymphedema subjects and 27 normals in our attempt to discover protein analytes that can distinguish diseased individuals from controls. To minimize technical and biologically irrelevant variation, we first identified potential candidates by performing transcriptional microarray analysis on paired diseased and normal skin specimens sampled from the same individuals. We focused our attention on genes with corresponding protein products that are secreted and took these candidates forward to a protein multiplex assay applied to diseased and normal subjects. We developed a logistic regression-based model on an eventual group of six proteins and validated our system on a separate cohort of study subjects. The area under the receiver operating characteristic curve was calculated to be 0.87 (95% CI : 0.75 to 0.97).We have developed an accurate bioassay utilizing proteins representing four central pathogenetic modalities of the disease: lymphangiogenesis, inflammation, fibrosis, and lipid metabolism, suggesting that these proteins are directly related to the pathogenesis of the tissue pathology in lymphatic vascular insufficiency. Further studies are warranted to determine whether this newly-identified biomarker panel will possess utility as an instrument for in vitro diagnosis of early and latent disease; the ultimate applicability to risk stratification, quantitation of disease burden, and response to therapy can easily be envisioned.

    View details for DOI 10.1371/journal.pone.0052021

    View details for PubMedID 23272198

  • Dose-dependent Differential Impact of Estrogen Replacement on Abdominal Aortic Aneurysm Formation in a Murine Model Toh, R., Raaz, U., Nakagami, F., Azuma, J., Maegdefessel, L., Deng, A., Spin, J. M., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2012
  • Microrna-24 Regulates Inflammation and Calcification During Abdominal Aortic Aneurysm Development Through Targeting Ykl-40 Maegdefessel, L., Raaz, U., Toh, R., Deng, A., Chernogubova, E., Eriksson, P., Hamsten, A., Spin, J. M., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2012
  • Coronary risk assessment among intermediate risk patients using a clinical and biomarker based algorithm developed and validated in two population cohorts CURRENT MEDICAL RESEARCH AND OPINION Cross, D. S., McCarty, C. A., Hytopoulos, E., Beggs, M., Nolan, N., Harrington, D. S., Hastie, T., Tibshirani, R., Tracy, R. P., Psaty, B. M., McClelland, R., Tsao, P. S., Quertermous, T. 2012; 28 (11): 1819-1830

    Abstract

    Many coronary heart disease (CHD) events occur in individuals classified as intermediate risk by commonly used assessment tools. Over half the individuals presenting with a severe cardiac event, such as myocardial infarction (MI), have at most one risk factor as included in the widely used Framingham risk assessment. Individuals classified as intermediate risk, who are actually at high risk, may not receive guideline recommended treatments. A clinically useful method for accurately predicting 5-year CHD risk among intermediate risk patients remains an unmet medical need.This study sought to develop a CHD Risk Assessment (CHDRA) model that improves 5-year risk stratification among intermediate risk individuals.Assay panels for biomarkers associated with atherosclerosis biology (inflammation, angiogenesis, apoptosis, chemotaxis, etc.) were optimized for measuring baseline serum samples from 1084 initially CHD-free Marshfield Clinic Personalized Medicine Research Project (PMRP) individuals. A multivariable Cox regression model was fit using the most powerful risk predictors within the clinical and protein variables identified by repeated cross-validation. The resulting CHDRA algorithm was validated in a Multiple-Ethnic Study of Atherosclerosis (MESA) case-cohort sample.A CHDRA algorithm of age, sex, diabetes, and family history of MI, combined with serum levels of seven biomarkers (CTACK, Eotaxin, Fas Ligand, HGF, IL-16, MCP-3, and sFas) yielded a clinical net reclassification index of 42.7% (p < 0.001) for MESA patients with a recalibrated Framingham 5-year intermediate risk level. Across all patients, the model predicted acute coronary events (hazard ratio = 2.17, p < 0.001), and remained an independent predictor after Framingham risk factor adjustments.These include the slightly different event definition with the MESA samples and inability to include PMRP fatal CHD events.A novel risk score of serum protein levels plus clinical risk factors, developed and validated in independent cohorts, demonstrated clinical utility for assessing the true risk of CHD events in intermediate risk patients. Improved accuracy in cardiovascular risk classification could lead to improved preventive care and fewer deaths.

    View details for DOI 10.1185/03007995.2012.742878

    View details for Web of Science ID 000310985600009

    View details for PubMedID 23092312

    View details for PubMedCentralID PMC3666558

  • Wall shear stress is decreased in the pulmonary arteries of patients with pulmonary arterial hypertension: An image-based, computational fluid dynamics study. Pulmonary circulation Tang, B. T., Pickard, S. S., Chan, F. P., Tsao, P. S., Taylor, C. A., Feinstein, J. A. 2012; 2 (4): 470-476

    Abstract

    Previous clinical studies in pulmonary arterial hypertension (PAH) have concentrated predominantly on distal pulmonary vascular resistance, its contribution to the disease process, and response to therapy. However, it is well known that biomechanical factors such as shear stress have an impact on endothelial health and dysfunction in other parts of the vasculature. This study tested the hypothesis that wall shear stress is reduced in the proximal pulmonary arteries of PAH patients with the belief that reduced shear stress may contribute to pulmonary endothelial cell dysfunction and as a result, PAH progression. A combined MRI and computational fluid dynamics (CFD) approach was used to construct subject-specific pulmonary artery models and quantify flow features and wall shear stress (WSS) in five PAH patients with moderate-to-severe disease and five age- and sex-matched controls. Three-dimensional model reconstruction showed PAH patients have significantly larger main, right, and left pulmonary artery diameters (3.5 ± 0.4 vs. 2.7 ± 0.1 cm, P = 0.01; 2.5 ± 0.4 vs. 1.9 ± 0.2 cm, P = 0.04; and 2.6 ± 0.4 vs. 2.0 ± 0.2 cm, P = 0.01, respectively), and lower cardiac output (3.7 ± 1.2 vs. 5.8 ± 0.6 L/min, P = 0.02.). CFD showed significantly lower time-averaged central pulmonary artery WSS in PAH patients compared to controls (4.3 ± 2.8 vs. 20.5 ± 4.0 dynes/cm(2), P = 0.0004). Distal WSS was not significantly different. A novel method of measuring WSS was utilized to demonstrate for the first time that WSS is altered in some patients with PAH. Using computational modeling in patient-specific models, WSS was found to be significantly lower in the proximal pulmonary arteries of PAH patients compared to controls. Reduced WSS in proximal pulmonary arteries may play a role in the pathogenesis and progression of PAH. This data may serve as a basis for future in vitro studies of, for example, effects of WSS on gene expression.

    View details for DOI 10.4103/2045-8932.105035

    View details for PubMedID 23372931

  • In vivo, ex vivo, and in vitro studies on apelin's effect on myocardial glucose uptake PEPTIDES Xu, S., Han, P., Huang, M., Wu, J. C., Chang, C., Tsao, P. S., Yue, P. 2012; 37 (2): 320-326

    Abstract

    Apelin is an endogenous peptide hormone recently implicated in glucose homeostasis. However, whether apelin affects glucose uptake in myocardial tissue remains undetermined. In this study, we utilized in vivo, ex vivo and in vitro methods to study apelin's effect on myocardial glucose uptake. Pyroglutamated apelin-13 (2mg/kg/day) was administered to C57BL6/J mice for 7 days. In vivo myocardial glucose uptake was measured by FDG-PET scanning, and GLUT4 translocation was assessed by immunofluorescence imaging. For in vitro studies, differentiated H9C2 cardiomyoblasts were exposed to pyroglutamated apelin-13 (100 nM) for 2h. To test their involvement in apelin-stimulated myocardial glucose uptake, the energy sensing protein kinase AMPK were inhibited by pharmacologic inhibition (compound C) and RNA interference. IRS-1 phosphorylation was assessed by western blotting using an antibody directed against IRS-1 Ser-789-phosphorylated form. We found that apelin increased myocardial glucose uptake and GLUT4 membrane translocation in C57BL6/J mice. Apelin was also sufficient to increase glucose uptake in H9C2 cells. Apelin-mediated glucose uptake was significantly decreased by AMPK inhibition. Finally, apelin increased IRS-1 Ser-789 phosphorylation in an AMPK-dependent manner. The results of our study demonstrated that apelin increases myocardial glucose uptake through a pathway involving AMPK. Apelin also facilitates IRS-1 Ser-789 phosphorylation, suggesting a novel mechanism for its effects on glucose uptake.

    View details for DOI 10.1016/j.peptides.2012.08.004

    View details for Web of Science ID 000310047700020

    View details for PubMedID 22906703

  • Apolipoprotein(a) Genetic Sequence Variants Associated With Systemic Atherosclerosis and Coronary Atherosclerotic Burden But Not With Venous Thromboembolism JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Helgadottir, A., Gretarsdottir, S., Thorleifsson, G., Holm, H., Patel, R. S., Gudnason, T., Jones, G. T., van Rij, A. M., Eapen, D. J., Baas, A. F., Tregouet, D., Morange, P., Emmerich, J., Lindblad, B., Gottsater, A., Kiemeny, L. A., Lindholt, J. S., Sakalihasan, N., Ferrell, R. E., Carey, D. J., Elmore, J. R., Tsao, P. S., Grarup, N., Jorgensen, T., Witte, D. R., Hansen, T., Pedersen, O., Pola, R., Gaetani, E., Magnadottir, H. B., Wijmenga, C., Tromp, G., Ronkainen, A., Ruigrok, Y. M., Blankensteijn, J. D., Mueller, T., Wells, P. S., Corral, J., Manuel Soria, J., Carlos Souto, J., Peden, J. F., Jalilzadeh, S., Mayosi, B. M., Keavney, B., Strawbridge, R. J., Sabater-Lleal, M., Gertow, K., Baldassarre, D., Nyyssonen, K., Rauramaa, R., Smit, A. J., Mannarino, E., Giral, P., Tremoli, E., de Faire, U., Humphries, S. E., Hamsten, A., Haraldsdottir, V., Olafsson, I., Magnusson, M. K., Samani, N. J., Levey, A. I., Markus, H. S., Kostulas, K., Dichgans, M., Berger, K., Kuhlenbaeumer, G., Ringelstein, E. B., Stoll, M., Seedorf, U., Rothwell, P. M., Powell, J. T., Kuivaniemi, H., Onundarson, P. T., Valdimarsson, E., Matthiasson, S. E., Gudbjartsson, D. F., Thorgeirsson, G., Quyyumi, A. A., Watkins, H., Farrall, M., Thorsteinsdottir, U., Stefansson, K. 2012; 60 (8): 722-729

    Abstract

    The purpose of this study is investigate the effects of variants in the apolipoprotein(a) gene (LPA) on vascular diseases with different atherosclerotic and thrombotic components.It is unclear whether the LPA variants rs10455872 and rs3798220, which correlate with lipoprotein(a) levels and coronary artery disease (CAD), confer susceptibility predominantly via atherosclerosis or thrombosis.The 2 LPA variants were combined and examined as LPA scores for the association with ischemic stroke (and TOAST [Trial of Org 10172 in Acute Stroke Treatment] subtypes) (effective sample size [n(e)] = 9,396); peripheral arterial disease (n(e) = 5,215); abdominal aortic aneurysm (n(e) = 4,572); venous thromboembolism (n(e) = 4,607); intracranial aneurysm (n(e) = 1,328); CAD (n(e) = 12,716), carotid intima-media thickness (n = 3,714), and angiographic CAD severity (n = 5,588).LPA score was associated with ischemic stroke subtype large artery atherosclerosis (odds ratio [OR]: 1.27; p = 6.7 × 10(-4)), peripheral artery disease (OR: 1.47; p = 2.9 × 10(-14)), and abdominal aortic aneurysm (OR: 1.23; p = 6.0 × 10(-5)), but not with the ischemic stroke subtypes cardioembolism (OR: 1.03; p = 0.69) or small vessel disease (OR: 1.06; p = 0.52). Although the LPA variants were not associated with carotid intima-media thickness, they were associated with the number of obstructed coronary vessels (p = 4.8 × 10(-12)). Furthermore, CAD cases carrying LPA risk variants had increased susceptibility to atherosclerotic manifestations outside of the coronary tree (OR: 1.26; p = 0.0010) and had earlier onset of CAD (-1.58 years/allele; p = 8.2 × 10(-8)) than CAD cases not carrying the risk variants. There was no association of LPA score with venous thromboembolism (OR: 0.97; p = 0.63) or intracranial aneurysm (OR: 0.85; p = 0.15).LPA sequence variants were associated with atherosclerotic burden, but not with primarily thrombotic phenotypes.

    View details for DOI 10.1016/j.jacc.2012.01.078

    View details for Web of Science ID 000307463800004

  • Apolipoprotein(a) genetic sequence variants associated with systemic atherosclerosis and coronary atherosclerotic burden but not with venous thromboembolism. Journal of the American College of Cardiology Helgadottir, A., Gretarsdottir, S., Thorleifsson, G., Holm, H., Patel, R. S., Gudnason, T., Jones, G. T., van Rij, A. M., Eapen, D. J., Baas, A. F., Tregouet, D., Morange, P., Emmerich, J., Lindblad, B., Gottsäter, A., Kiemeny, L. A., Lindholt, J. S., Sakalihasan, N., Ferrell, R. E., Carey, D. J., Elmore, J. R., Tsao, P. S., Grarup, N., Jørgensen, T., Witte, D. R., Hansen, T., Pedersen, O., Pola, R., Gaetani, E., Magnadottir, H. B., Wijmenga, C., Tromp, G., Ronkainen, A., Ruigrok, Y. M., Blankensteijn, J. D., Mueller, T., Wells, P. S., Corral, J., Soria, J. M., Souto, J. C., Peden, J. F., Jalilzadeh, S., Mayosi, B. M., Keavney, B., Strawbridge, R. J., Sabater-Lleal, M., Gertow, K., Baldassarre, D., Nyyssönen, K., Rauramaa, R., Smit, A. J., Mannarino, E., Giral, P., Tremoli, E., de Faire, U., Humphries, S. E., Hamsten, A., Haraldsdottir, V., Olafsson, I., Magnusson, M. K., Samani, N. J., Levey, A. I., Markus, H. S., Kostulas, K., Dichgans, M., Berger, K., Kuhlenbäumer, G., Ringelstein, E. B., Stoll, M., Seedorf, U., Rothwell, P. M., Powell, J. T., Kuivaniemi, H., Onundarson, P. T., Valdimarsson, E., Matthiasson, S. E., Gudbjartsson, D. F., Thorgeirsson, G., Quyyumi, A. A., Watkins, H., Farrall, M., Thorsteinsdottir, U., Stefansson, K. 2012; 60 (8): 722-729

    Abstract

    The purpose of this study is investigate the effects of variants in the apolipoprotein(a) gene (LPA) on vascular diseases with different atherosclerotic and thrombotic components.It is unclear whether the LPA variants rs10455872 and rs3798220, which correlate with lipoprotein(a) levels and coronary artery disease (CAD), confer susceptibility predominantly via atherosclerosis or thrombosis.The 2 LPA variants were combined and examined as LPA scores for the association with ischemic stroke (and TOAST [Trial of Org 10172 in Acute Stroke Treatment] subtypes) (effective sample size [n(e)] = 9,396); peripheral arterial disease (n(e) = 5,215); abdominal aortic aneurysm (n(e) = 4,572); venous thromboembolism (n(e) = 4,607); intracranial aneurysm (n(e) = 1,328); CAD (n(e) = 12,716), carotid intima-media thickness (n = 3,714), and angiographic CAD severity (n = 5,588).LPA score was associated with ischemic stroke subtype large artery atherosclerosis (odds ratio [OR]: 1.27; p = 6.7 × 10(-4)), peripheral artery disease (OR: 1.47; p = 2.9 × 10(-14)), and abdominal aortic aneurysm (OR: 1.23; p = 6.0 × 10(-5)), but not with the ischemic stroke subtypes cardioembolism (OR: 1.03; p = 0.69) or small vessel disease (OR: 1.06; p = 0.52). Although the LPA variants were not associated with carotid intima-media thickness, they were associated with the number of obstructed coronary vessels (p = 4.8 × 10(-12)). Furthermore, CAD cases carrying LPA risk variants had increased susceptibility to atherosclerotic manifestations outside of the coronary tree (OR: 1.26; p = 0.0010) and had earlier onset of CAD (-1.58 years/allele; p = 8.2 × 10(-8)) than CAD cases not carrying the risk variants. There was no association of LPA score with venous thromboembolism (OR: 0.97; p = 0.63) or intracranial aneurysm (OR: 0.85; p = 0.15).LPA sequence variants were associated with atherosclerotic burden, but not with primarily thrombotic phenotypes.

    View details for DOI 10.1016/j.jacc.2012.01.078

    View details for PubMedID 22898070

  • Vascular smooth muscle cell phenotypic plasticity: focus on chromatin remodelling CARDIOVASCULAR RESEARCH Spin, J. M., Maegdefessel, L., Tsao, P. S. 2012; 95 (2): 147-155

    Abstract

    Differentiated vascular smooth muscle cells (SMCs) retain the capacity to modify their phenotype in response to inflammation or injury. This phenotypic switching is a crucial component of vascular disease, and is partly dependent on epigenetic regulation. An appreciation has been building in the literature for the essential role chromatin remodelling plays both in SMC lineage determination and in influencing changes in SMC behaviour and state. This process includes numerous chromatin regulatory elements and pathways such as histone acetyltransferases, deacetylases, and methyltransferases and other factors that act at SMC-specific marker sites to silence or permit access to the cellular transcriptional machinery and on other key regulatory elements such as myocardin and Kruppel-like factor 4 (KLF4). Various stimuli known to alter the SMC phenotype, such as transforming growth factor beta (TGF-β), platelet-derived growth factor (PDGF), oxidized phospholipids, and retinoic acid, appear to act in part through effects upon SMC chromatin structure. In recent years, specific covalent histone modifications that appear to establish SMC determinacy have been identified, while others alter the differentiation state. In this article, we review the mechanisms of chromatin remodelling as it applies to the SMC phenotype.

    View details for DOI 10.1093/cvr/cvs098

    View details for Web of Science ID 000306141100004

    View details for PubMedID 22362814

    View details for PubMedCentralID PMC3388815

  • Using plasma proteomic analysis for venous thromboembolism risk stratification in patients with advanced gastrointestinal cancers Itakura, H., Holzer, A. K., Hofmann, L. V., Tsao, P. S. AMER SOC CLINICAL ONCOLOGY. 2012
  • Human Internal Mammary Artery (IMA) Transplantation and Stenting: A Human Model to Study the Development of In-Stent Restenosis JOVE-JOURNAL OF VISUALIZED EXPERIMENTS Hua, X., Deuse, T., Michelakis, E. D., Haromy, A., Tsao, P. S., Maegdefessel, L., Erben, R. G., Bergow, C., Behnisch, B. B., Reichenspurner, H., Robbins, R. C., Schrepfer, S. 2012

    View details for DOI 10.3791/3663

    View details for Web of Science ID 000209223000016

  • Three-Dimensional Microstructural Changes in Murine Abdominal Aortic Aneurysms Quantified Using Immunofluorescent Array Tomography JOURNAL OF HISTOCHEMISTRY & CYTOCHEMISTRY Saatchi, S., Azuma, J., Wanchoo, N., Smith, S. J., Yock, P. G., Taylor, C. A., Tsao, P. S. 2012; 60 (2): 97-109

    Abstract

    This study investigated the spatial and temporal remodeling of blood vessel wall microarchitecture and cellular morphology during abdominal aortic aneurysm (AAA) development using immunofluorescent array tomography (IAT), a high-resolution three-dimensional (3D) microscopy technology, in the murine model. Infrarenal aortas of C57BL6 mice (N=20) were evaluated at 0, 7, and 28 days after elastase or heat-inactivated elastase perfusion. Custom algorithms quantified volume fractions (VF) of elastin, smooth muscle cell (SMC) actin, and adventitial collagen type I, as well as elastin thickness, elastin fragmentation, non-adventitial wall thickness, and nuclei amount. The 3D renderings depicted elastin and collagen type I degradation and SMC morphological changes. Elastin VF decreased 37.5% (p<0.01), thickness decreased 48.9%, and fragmentation increased 449.7% (p<0.001) over 28 days. SMC actin VF decreased 78.3% (p<0.001) from days 0 to 7 and increased 139.7% (p<0.05) from days 7 to 28. Non-adventitial wall thickness increased 61.1%, medial nuclei amount increased 159.1% (p<0.01), and adventitial collagen type I VF decreased 64.1% (p<0.001) over 28 days. IAT and custom image analysis algorithms have enabled robust quantification of vessel wall content, microstructure, and organization to help elucidate the dynamics of vascular remodeling during AAA development.

    View details for DOI 10.1369/0022155411433066

    View details for Web of Science ID 000299481300001

    View details for PubMedID 22140132

    View details for PubMedCentralID PMC3351119

  • miR-29b Participates in Early Aneurysm Development in Marfan Syndrome CIRCULATION RESEARCH Merk, D. R., Chin, J. T., Dake, B. A., Maegdefessel, L., Miller, M. O., Kimura, N., Tsao, P. S., Iosef, C., Berry, G. J., Mohr, F. W., Spin, J. M., Alvira, C. M., Robbins, R. C., Fischbein, M. P. 2012; 110 (2): 312-?

    Abstract

    Marfan syndrome (MFS) is a systemic connective tissue disorder notable for the development of aortic root aneurysms and the subsequent life-threatening complications of aortic dissection and rupture. Underlying fibrillin-1 gene mutations cause increased transforming growth factor-β (TGF-β) signaling. Although TGF-β blockade prevents aneurysms in MFS mouse models, the mechanisms through which excessive TGF-β causes aneurysms remain ill-defined.We investigated the role of microRNA-29b (miR-29b) in aneurysm formation in MFS.Using quantitative polymerase chain reaction, we discovered that miR-29b, a microRNA regulating apoptosis and extracellular matrix synthesis/deposition genes, is increased in the ascending aorta of Marfan (Fbn1(C1039G/+)) mice. Increased apoptosis, assessed by increased cleaved caspase-3 and caspase-9, enhanced caspase-3 activity, and decreased levels of the antiapoptotic proteins, Mcl-1 and Bcl-2, were found in the Fbn1(C1039G/+) aorta. Histological evidence of decreased and fragmented elastin was observed exclusively in the Fbn1(C1039G/+) ascending aorta in association with repressed elastin mRNA and increased matrix metalloproteinase-2 expression and activity, both targets of miR-29b. Evidence of decreased activation of nuclear factor κB, a repressor of miR-29b, and a factor suppressed by TGF-β, was also observed in Fbn1(C1039G/+) aorta. Furthermore, administration of a nuclear factor κB inhibitor increased miR-29b levels, whereas TGF-β blockade or losartan effectively decreased miR-29b levels in Fbn1(C1039G/+) mice. Finally, miR-29b blockade by locked nucleic acid antisense oligonucleotides prevented early aneurysm development, aortic wall apoptosis, and extracellular matrix deficiencies.We identify increased miR-29b expression as key to the pathogenesis of early aneurysm development in MFS by regulating aortic wall apoptosis and extracellular matrix abnormalities.

    View details for DOI 10.1161/CIRCRESAHA.111.253740

    View details for PubMedID 22116819

  • Human internal mammary artery (IMA) transplantation and stenting: a human model to study the development of in-stent restenosis. Journal of visualized experiments : JoVE Hua, X., Deuse, T., Michelakis, E. D., Haromy, A., Tsao, P. S., Maegdefessel, L., Erben, R. G., Bergow, C., Behnisch, B. B., Reichenspurner, H., Robbins, R. C., Schrepfer, S. 2012: e3663-?

    Abstract

    Preclinical in vivo research models to investigate pathobiological and pathophysiological processes in the development of intimal hyperplasia after vessel stenting are crucial for translational approaches (1,2). The commonly used animal models include mice, rats, rabbits, and pigs (3-5). However, the translation of these models into clinical settings remains difficult, since those biological processes are already studied in animal vessels but never performed before in human research models (6,7). In this video we demonstrate a new humanized model to overcome this translational gap. The shown procedure is reproducible, easy, and fast to perform and is suitable to study the development of intimal hyperplasia and the applicability of diverse stents. This video shows how to perform the stent technique in human vessels followed by transplantation into immunodeficient rats, and identifies the origin of proliferating cells as human.

    View details for DOI 10.3791/3663

    View details for PubMedID 22617624

  • Low- and High-Dose Plant and Marine (n-3) Fatty Acids Do Not Affect Plasma Inflammatory Markers in Adults with Metabolic Syndrome JOURNAL OF NUTRITION Dewell, A., Marvasti, F. F., Harris, W. S., Tsao, P., Gardner, C. D. 2011; 141 (12): 2166-2171

    Abstract

    Chronic inflammation is considered to play a role in the development of cardiovascular disease. Various (n-3) fatty acids (FA) have been reported to have antiinflammatory effects, but there is a lack of consensus in this area, particularly in regard to optimal source(s) and dose(s). This study aimed to determine the effects of high and low doses of (n-3) FA from plant and marine sources on plasma inflammatory marker concentrations. One-hundred adults with metabolic syndrome were randomly assigned to a low or high dose of plant- (2.2 or 6.6 g/d α-linolenic acid) or marine- (1.2 or 3.6 g/d EPA and DHA) derived (n-3) FA or placebo for 8 wk, using a parallel arm design (n = 20/arm). Fasting blood samples collected at 0, 4, and 8 wk were analyzed for concentrations of monocyte chemotactic protein-1 (MCP-1), IL-6, and soluble intercellular adhesion molecule-1 (sICAM-1) and for cardiovascular risk factors. Baseline concentrations across all 5 groups combined were (mean ± SD) 103 ± 32 ng/L for MCP-1, 1.06 ± 0.56 ng/L for IL-6, and 0.197 ± 0.041 ng/L for sICAM-1. There were no significant differences in 8-wk changes in plasma inflammatory marker concentrations among the 5 groups. Plasma TG and blood pressure decreased significantly more and the LDL cholesterol concentration increased more in the high-dose fish oil group compared to the 8-wk changes in some of the other 4 groups (P ≤ 0.04). In conclusion, no beneficial effects were detected for any of the 3 inflammatory markers investigated in response to (n-3) FA in adults with metabolic syndrome regardless of dose or source.

    View details for DOI 10.3945/jn.111.142240

    View details for Web of Science ID 000297387200011

    View details for PubMedID 22031659

    View details for PubMedCentralID PMC3223874

  • In Vivo Bioluminescence Imaging of Inducible Nitric Oxide Synthase Gene Expression in Vascular Inflammation MOLECULAR IMAGING AND BIOLOGY Terashima, M., Ehara, S., Yang, E., Kosuge, H., Tsao, P. S., Quertermous, T., Contag, C. H., McConnell, M. V. 2011; 13 (6): 1061-1066

    Abstract

    Inflammation plays a critical role in atherosclerosis and is associated with upregulation of inducible nitric oxide synthase (iNOS). We studied bioluminescence imaging (BLI) to track iNOS gene expression in a murine model of vascular inflammation.Macrophage-rich vascular lesions were induced by carotid ligation plus high-fat diet and streptozotocin-induced diabetes in 18 iNOS-luc reporter mice. In vivo iNOS expression was imaged serially by BLI over 14 days, followed by in situ BLI and histology.BLI signal from ligated carotids increased over 14 days (9.7 ± 4.4 × 10(3 ) vs. 4.4 ± 1.7 × 10(3) photons/s/cm(2)/sr at baseline, p < 0.001 vs. baseline, p < 0.05 vs. sham controls). Histology confirmed substantial macrophage infiltration, with iNOS and luciferase expression, only in ligated left carotid arteries and not controls.BLI allows in vivo detection of iNOS expression in murine carotid lesions and may provide a valuable approach for monitoring vascular gene expression and inflammation in small animal models.

    View details for DOI 10.1007/s11307-010-0451-5

    View details for PubMedID 21057879

  • Microrna-21 Regulates Expansion of Abdominal Aortic Aneurysms Through the PTEN/PI3K/AKT Pathway Scientific Sessions of the American-Heart-Association/Resuscitation Science Symposium Maegdefessel, L., Azuma, J., Deng, A., Toh, R. M., Merk, D. R., Raiesdana, A., Leeper, N. J., Spin, J. M., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2011
  • Nicotine-Augmented Abdominal Aortic Aneurysms are Regulated by MicroRNA-29b Scientific Sessions of the American-Heart-Association/Resuscitation Science Symposium Maegdefessel, L., Azuma, J., Merk, D. R., Toh, R. M., Deng, A., Chin, J. P., Spin, J. M., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2011
  • Human Leukocyte Antigen I Knockdown Human Embryonic Stem Cells Induce Host Ignorance and Achieve Prolonged Xenogeneic Survival Annual Meeting of the American-Heart-Association Deuse, T., Seifert, M., Phillips, N., Fire, A., Tyan, D., Kay, M., Tsao, P. S., Hua, X., Velden, J., Eiermann, T., Volk, H., Reichenspurner, H., Robbins, R. C., Schrepfer, S. LIPPINCOTT WILLIAMS & WILKINS. 2011: S3–S9

    Abstract

    Although human embryonic stem cells (hESC) have enormous potential for cell replacement therapy of heart failure, immune rejection of hESC derivatives inevitably would occur after transplantation. We therefore aimed to generate a hypoantigeneic hESC line with improved survival characteristics.Using various in vivo, nonischemic, hindlimb xenotransplant models (immunocompetent and defined immunodefective mouse strains) as well as human in vitro T-cell and natural killer (NK)-cell assays, we revealed a central role for T cells in mediating hESC rejection. The NK-cell susceptibility of hESC in vivo was found to be low, and the NK response to hESC challenge in vitro was negligible. To reduce the antigenicity of hESC, we successfully generated human leukocyte antigen (HLA) I knockdown cells (hESC(siRNA+IB)) using both HLA I RNA interference (siRNA) and intrabody (IB) technology. HLA I expression was ≈99% reduced after 7 days and remained low for weeks. Cellular immune recognition of these hESC(siRNA+IB) was strongly reduced in both xenogeneic and allogeneic settings. Immune rejection was profoundly mitigated after hESC(siRNA+IB) transplantation into immunocompetent mice, and even long-term graft survival was achieved in one third of the animals without any immunosuppression. The survival benefit of hESC(siRNA+IB) was further confirmed under ischemic conditions in a left anterior descending coronary artery ligation model.HLA I knockdown hESC(siRNA+IB) provoke T-cell ignorance and experience largely mitigated xenogeneic rejection. By generating hypoantigeneic hESC lines, the generation of acceptable hESC derivatives may become a practical concept and push cell replacement strategies forward.

    View details for DOI 10.1161/CIRCULATIONAHA.111.020727

    View details for Web of Science ID 000294782800001

    View details for PubMedID 21911816

  • Transcriptional profiling and network analysis of the murine angiotensin II-induced abdominal aortic aneurysm PHYSIOLOGICAL GENOMICS Spin, J. M., Hsu, M., Azuma, J., Tedesco, M. M., Deng, A., Dyer, J. S., Maegdefessel, L., Dalman, R. L., Tsao, P. S. 2011; 43 (17): 993-1003

    Abstract

    We sought to characterize temporal gene expression changes in the murine angiotensin II (ANG II)-ApoE-/- model of abdominal aortic aneurysm (AAA). Aortic ultrasound measurements were obtained over the 28-day time-course. Harvested suprarenal aortic segments were evaluated with whole genome expression profiling at 7, 14, and 28 days using the Agilent Whole Mouse Genome microarray platform and Statistical Analysis of Microarrays at a false discovery rate of <1%. A group of angiotensin-treated mice experienced contained rupture (CR) within 7 days and were analyzed separately. Progressive aortic dilatation occurred throughout the treatment period. However, the numerous early expression differences between ANG II-treated and control were not sustained over time. Ontologic analysis revealed widespread upregulation of inflammatory, immune, and matrix remodeling genes with ANG II treatment, among other pathways such as apoptosis, cell cycling, angiogenesis, and p53 signaling. CR aneurysms displayed significant decreases in TGF-β/BMP-pathway signaling, MAPK signaling, and ErbB signaling genes vs. non-CR/ANG II-treated samples. We also performed literature-based network analysis, extracting numerous highly interconnected genes associated with aneurysm development such as Spp1, Myd88, Adam17 and Lox. 1) ANG II treatment induces extensive early differential expression changes involving abundant signaling pathways in the suprarenal abdominal aorta, particularly wide-ranging increases in inflammatory genes with aneurysm development. 2) These gene expression changes appear to dissipate with time despite continued growth, suggesting that early changes in gene expression influence disease progression in this AAA model, and that the aortic tissue adapts to prolonged ANG II infusion. 3) Network analysis identified nexus genes that may constitute aneurysm biomarkers or therapeutic targets.

    View details for DOI 10.1152/physiolgenomics.00044.2011

    View details for Web of Science ID 000294730000002

    View details for PubMedID 21712436

    View details for PubMedCentralID PMC3180735

  • Apelin and insulin resistance: Another arrow for the quiver? JOURNAL OF DIABETES Xu, S., Tsao, P. S., Yue, P. 2011; 3 (3): 225-231

    Abstract

    Apelin is a newly discovered peptide hormone that has recently been linked to insulin resistance and obesity. Data collected from both the clinical and basic research settings show that apelin: (i) is correlated with the states of insulin resistance and obesity; (ii) stimulates glucose utilization; (iii) decreases insulin secretion; and (iv) negatively regulates catecholamine-mediated lipolysis. These and other lines of evidence demonstrate that apelin may be a potentially viable candidate in the search for treatments for Type 2 diabetes and the insulin resistance (metabolic syndrome). The present review summarizes the literature on the regulation by apelin of glucose and lipid metabolism and the signaling pathways involved.

    View details for DOI 10.1111/j.1753-0407.2011.00132.x

    View details for Web of Science ID 000307064700009

    View details for PubMedID 21631898

    View details for PubMedCentralID PMC3156858

  • Immunobiology of naive and genetically modified HLA-class-I-knockdown human embryonic stem cells JOURNAL OF CELL SCIENCE Deuse, T., Seifert, M., Phillips, N., Fire, A., Tyan, D., Kay, M., Tsao, P. S., Hua, X., Velden, J., Eiermann, T., Volk, H., Reichenspurner, H., Robbins, R. C., Schrepfer, S. 2011; 124 (17): 3029-3037

    Abstract

    Human embryonic stem cells (hESCs) can serve as a universal cell source for emerging cell or tissue replacement strategies, but immune rejection of hESC derivatives remains an unsolved problem. Here, we sought to describe the mechanisms of rejection for naïve hESCs and upon HLA class I (HLA I) knockdown (hESC(KD)). hESCs were HLA I-positive but negative for HLA II and co-stimulatory molecules. Transplantation of naïve hESC into immunocompetent Balb/c mice induced substantial T helper cell 1 and 2 (Th1 and Th2) responses with rapid cell death, but hESCs survived in immunodeficient SCID-beige recipients. Histology revealed mainly macrophages and T cells, but only scattered natural killer (NK) cells. A surge of hESC-specific antibodies against hESC class I, but not class II antigens, was observed. Using HLA I RNA interference and intrabody technology, HLA I surface expression of hESC(KD) was 88%-99% reduced. T cell activation after hESC(KD) transplantation into Balb/c was significantly diminished, antibody production was substantially alleviated, the levels of graft-infiltrating immune cells were reduced and the survival of hESC(KD) was prolonged. Because of their very low expression of stimulatory NK ligands, NK-susceptibility of naïve hESCs and hESC(KD) was negligible. Thus, HLA I recognition by T cells seems to be the primary mechanism of hESC recognition, and T cells, macrophages and hESC-specific antibodies participate in hESC killing.

    View details for DOI 10.1242/jcs.087718

    View details for Web of Science ID 000294419200015

    View details for PubMedID 21878509

  • Detecting Drug Interactions From Adverse-Event Reports: Interaction Between Paroxetine and Pravastatin Increases Blood Glucose Levels CLINICAL PHARMACOLOGY & THERAPEUTICS Tatonetti, N. P., Denny, J. C., Murphy, S. N., Fernald, G. H., Krishnan, G., Castro, V., Yue, P., Tsau, P. S., Kohane, I., Roden, D. M., Altman, R. B. 2011; 90 (1): 133-142

    Abstract

    The lipid-lowering agent pravastatin and the antidepressant paroxetine are among the most widely prescribed drugs in the world. Unexpected interactions between them could have important public health implications. We mined the US Food and Drug Administration's (FDA's) Adverse Event Reporting System (AERS) for side-effect profiles involving glucose homeostasis and found a surprisingly strong signal for comedication with pravastatin and paroxetine. We retrospectively evaluated changes in blood glucose in 104 patients with diabetes and 135 without diabetes who had received comedication with these two drugs, using data in electronic medical record (EMR) systems of three geographically distinct sites. We assessed the mean random blood glucose levels before and after treatment with the drugs. We found that pravastatin and paroxetine, when administered together, had a synergistic effect on blood glucose. The average increase was 19 mg/dl (1.0 mmol/l) overall, and in those with diabetes it was 48 mg/dl (2.7 mmol/l). In contrast, neither drug administered singly was associated with such changes in glucose levels. An increase in glucose levels is not a general effect of combined therapy with selective serotonin reuptake inhibitors (SSRIs) and statins.

    View details for DOI 10.1038/clpt.2011.83

    View details for Web of Science ID 000291853800023

    View details for PubMedID 21613990

    View details for PubMedCentralID PMC3216673

  • Apelin Increases Myocardial Glucose Uptake in Young but Not Older Diabetic Mice Xu, S., Azuma, J., Wu, J. C., Quertermous, T., Tsao, P. S., Yue, P. AMER DIABETES ASSOC. 2011: A689-A690
  • Apelin Expression in Human Adipocytes Is Associated with Insulin Sensitivity Yue, P., Abbasi, F. A., Deng, A. C., Mclaughlin, T. L., Reaven, G. M., Tsao, P. S. AMER DIABETES ASSOC. 2011: A480–A481
  • Asymmetric dimethylarginine impairs fibrinolytic activity in human umbilical vein endothelial cells via p38 MAPK and NF-kappa B pathways THROMBOSIS RESEARCH Zhang, Q., Chen, N., Qiu, W., Xu, X., Wang, D., Tsao, P. S., Jin, H. 2011; 128 (1): 42-46

    Abstract

    Asymmetric dimethylarginine (ADMA) is a potent endogenous inhibitor of nitric oxide (NO) synthase. An increased synthesis and/or a reduced catabolism of ADMA might contribute to the onset and progression of thrombosis. The present study was designed to evaluate the effect of ADMA on fibrinolytic factors in endothelial cells, and to investigate the cellular mechanisms.Human umbilical vein endothelial cells (HUVECs) were treated with different concentrations of ADMA for various periods; Then HUVECs were preincubated with NO precursor (L-arginine), MAPK inhibitors, or NF-κB inhibitor (PDTC) before ADMA treatment to repeat the experiment. Protein levels of tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1), and NF-κB activity were measured by ELISA; mRNA levels of tPA and PAI-1 were assayed by qRT-PCR; The activation of MAPK was characterized by western blot analysis.(1) ADMA decreased tPA antigen levels in time- and concentration-dependent manners, with the maximum effect of 30 μmol/L ADMA for 48h (control 109.01 ± 4.15 ng/ml vs ADMA 86.76 ± 5.95 ng/ml, p<0.01); (2) 30 μmol/L ADMA elevated antigen levels of PAI-1 in a time-dependent manner, with the maximum effect of 30 μmol/L ADMA for 48 h (control 2721.12 ± 278.02 ng/ml vs. ADMA 3435.78 ± 22.33ng/ml, p<0.05); (3) ADMA reduced tPA mRNA levels and increased PAI-1 mRNA levels; (4) L-arginine, SB203580 (p38 MAPK inhibitor) and PDTC attenuated the effects of ADMA on tPA and PAI-1 significantly. (5) ADMA induced a rapid phosphorylation of p38 MAPK, and stimulated NF-κB activity greatly.ADMA may accelerate thrombosis development by impairing fibrinolytic activity in vascular via inhibiting nitric oxide production and then activating its downstream p38 MAPK and NF-κB pathways.

    View details for DOI 10.1016/j.thromres.2011.02.013

    View details for Web of Science ID 000291383500008

    View details for PubMedID 21429569

  • The Use of Immunofluorescent Array Tomography to Study the Three-Dimensional Microstructure of Murine Blood Vessels CELLULAR AND MOLECULAR BIOENGINEERING Saatchi, S., Wanchoo, N., Azuma, J., Smith, S. J., Tsao, P. S., Yock, P. G., Taylor, C. A. 2011; 4 (2): 311-323
  • MicroRNA-26a Is a Novel Regulator of Vascular Smooth Muscle Cell Function JOURNAL OF CELLULAR PHYSIOLOGY Leeper, N. J., Raiesdana, A., Kojima, Y., Chun, H. J., Azuma, J., Maegdefessel, L., Kundu, R. K., Quertermous, T., Tsao, P. S., Spin, J. M. 2011; 226 (4): 1035-1043

    Abstract

    Aberrant smooth muscle cell (SMC) plasticity has been implicated in a variety of vascular disorders including atherosclerosis, restenosis, and abdominal aortic aneurysm (AAA) formation. While the pathways governing this process remain unclear, epigenetic regulation by specific microRNAs (miRNAs) has been demonstrated in SMCs. We hypothesized that additional miRNAs might play an important role in determining vascular SMC phenotype. Microarray analysis of miRNAs was performed on human aortic SMCs undergoing phenotypic switching in response to serum withdrawal, and identified 31 significantly regulated entities. We chose the highly conserved candidate miRNA-26a for additional studies. Inhibition of miRNA-26a accelerated SMC differentiation, and also promoted apoptosis, while inhibiting proliferation and migration. Overexpression of miRNA-26a blunted differentiation. As a potential mechanism, we investigated whether miRNA-26a influences TGF-β-pathway signaling. Dual-luciferase reporter assays demonstrated enhanced SMAD signaling with miRNA-26a inhibition, and the opposite effect with miRNA-26a overexpression in transfected human cells. Furthermore, inhibition of miRNA-26a increased gene expression of SMAD-1 and SMAD-4, while overexpression inhibited SMAD-1. MicroRNA-26a was also found to be downregulated in two mouse models of AAA formation (2.5- to 3.8-fold decrease, P < 0.02) in which enhanced switching from contractile to synthetic phenotype occurs. In summary, miRNA-26a promotes vascular SMC proliferation while inhibiting cellular differentiation and apoptosis, and alters TGF-β pathway signaling. MicroRNA-26a represents an important new regulator of SMC biology and a potential therapeutic target in AAA disease.

    View details for DOI 10.1002/jcp.22422

    View details for Web of Science ID 000287258800019

    View details for PubMedID 20857419

    View details for PubMedCentralID PMC3108574

  • Influences of Aortic Motion and Curvature on Vessel Expansion in Murine Experimental Aneurysms ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Goergen, C. J., Azuma, J., Barr, K. N., Magdefessel, L., Kallop, D. Y., Gogineni, A., Grewall, A., Weimer, R. M., Connolly, A. J., Dalman, R. L., Taylor, C. A., Tsao, P. S., Greve, J. M. 2011; 31 (2): 270-U102

    Abstract

    To quantitatively compare aortic curvature and motion with resulting aneurysm location, direction of expansion, and pathophysiological features in experimental abdominal aortic aneurysms (AAAs).MRI was performed at 4.7 T with the following parameters: (1) 3D acquisition for vessel geometry and (2) 2D cardiac-gated acquisition to quantify luminal motion. Male 24-week-old mice were imaged before and after AAA formation induced by angiotensin II (AngII)-filled osmotic pump implantation or infusion of elastase. AngII-induced AAAs formed near the location of maximum abdominal aortic curvature, and the leftward direction of expansion was correlated with the direction of suprarenal aortic motion. Elastase-induced AAAs formed in a region of low vessel curvature and had no repeatable direction of expansion. AngII significantly increased mean blood pressure (22.7 mm Hg, P<0.05), whereas both models showed a significant 2-fold decrease in aortic cyclic strain (P<0.05). Differences in patterns of elastin degradation and localization of fluorescent signal from protease-activated probes were also observed.The direction of AngII aneurysm expansion correlated with the direction of motion, medial elastin dissection, and adventitial remodeling. Anterior infrarenal aortic motion correlated with medial elastin degradation in elastase-induced aneurysms. Results from both models suggest a relationship between aneurysm pathological features and aortic geometry and motion.

    View details for DOI 10.1161/ATVBAHA.110.216481

    View details for Web of Science ID 000286376800010

    View details for PubMedID 21071686

    View details for PubMedCentralID PMC3024449

  • Human ferritin cages for imaging vascular macrophages BIOMATERIALS Terashima, M., Uchida, M., Kosuge, H., Tsao, P. S., Young, M. J., Conolly, S. M., Douglas, T., McConnell, M. V. 2011; 32 (5): 1430-1437

    Abstract

    Atherosclerosis is a leading cause of death worldwide. Macrophages are key components of vascular inflammation, which contributes to the development and complications of atherosclerosis. Ferritin, an iron storage and transport protein, has been found to accumulate in macrophages in human atherosclerotic plaques. We hypothesized that ferritin could serve as an intrinsic nano-platform to target delivery of imaging agents to vascular macrophages to detect high-risk atherosclerotic plaques. Here we show that engineered human ferritin protein cages, either conjugated to the fluorescent Cy5.5 molecule or encapsulating a magnetite nanoparticle, are taken up in vivo by macrophages in murine atherosclerotic carotid arteries and can be imaged by fluorescence and magnetic resonance imaging. These results indicate that human ferritin can serve as a nanoparticle platform to image vascular inflammation in vivo.

    View details for DOI 10.1016/j.biomaterials.2010.09.029

    View details for PubMedID 21074263

  • Selective Glucocorticoid Receptor (GR-II) Antagonist Reduces Body Weight Gain in Mice. Journal of nutrition and metabolism Asagami, T., Belanoff, J. K., Azuma, J., Blasey, C. M., Clark, R. D., Tsao, P. S. 2011; 2011: 235389-?

    Abstract

    Previous research has shown that mifepristone can prevent and reverse weight gain in animals and human subjects taking antipsychotic medications. This proof-of-concept study tested whether a more potent and selective glucocorticoid receptor antagonist could block dietary-induced weight gain and increase insulin sensitivity in mice. Ten-week-old, male, C57BL/6J mice were fed a diet containing 60% fat calories and water supplemented with 11% sucrose for 4 weeks. Groups (n = 8) received one of the following: CORT 108297 (80 mg/kg QD), CORT 108297 (40 mg/kg BID), mifepristone (30 mg/kg BID), rosiglitazone (10 mg/kg QD), or vehicle. Compared to mice receiving a high-fat, high-sugar diet plus vehicle, mice receiving a high-fat, high-sugar diet plus either mifepristone or CORT 108297 gained significantly less weight. At the end of the four week treatment period, mice receiving CORT 108297 40 mg/kg BID or CORT 108297 80 mg/kg QD also had significantly lower steady plasma glucose than mice receiving vehicle. However, steady state plasma glucose after treatment was not highly correlated with reduced weight gain, suggesting that the effect of the glucocorticoid receptor antagonist on insulin sensitivity may be independent of its mitigating effect on weight gain.

    View details for DOI 10.1155/2011/235389

    View details for PubMedID 21811679

    View details for PubMedCentralID PMC3146995

  • Apelin Decreases Lipolysis via G(q), G(i), and AMPK-Dependent Mechanisms ENDOCRINOLOGY Yue, P., Jin, H., Xu, S., Aillaud, M., Deng, A. C., Azuma, J., Kundu, R. K., Reaven, G. M., Quertermous, T., Tsao, P. S. 2011; 152 (1): 59-68

    Abstract

    The release of free fatty acids (FFAs) from adipocytes (i.e. lipolysis) is increased in obesity and is a contributory factor to the development of insulin resistance. A recently identified adipokine, apelin, is up-regulated in states of obesity. Although apelin is secreted by adipocytes, its functions in them remain largely unknown. To determine whether apelin affects lipolysis, FFA, glycerol, and leptin levels, as well as abdominal adiposity, were measured at baseline and after reintroduction of exogenous apelin in apelin-null mice. To examine apelin's effects in vitro, isoproterenol-induced FFA/glycerol release, and hormone-sensitive lipase (HSL) and acetyl CoA carboxylase phosphorylation were investigated in 3T3-L1 cells and isolated wild-type adipocytes. Serum FFA, glycerol, and leptin concentrations, as well as abdominal adiposity, were significantly increased in apelin-null vs. wild-type mice; these changes were ameliorated in response to exogenous apelin. Apelin also reduced isoproterenol-induced FFA release in adipocytes isolated from wild-type but not APJ-null mice. In 3T3-L1 cells and isolated adipocytes, apelin attenuated isoproterenol-induced FFA/glycerol release. Apelin's inhibition was reversed by pertussis toxin, the G(q) inhibitor glycoprotein antagonist 2A, and the AMP-activated protein kinase inhibitors compound C and dorsomorphin. Apelin increased HSL phosphorylation at Ser-565 and also abrogated isoproterenol-induced HSL phosphorylation at Ser-563. Notably, apelin increased acetyl CoA carboxylase phosphorylation, suggesting AMPK activation. In conclusion, apelin negatively regulates lipolysis. Its actions may be mediated by pathways involving G(q), G(i), and AMP-activated protein kinase.

    View details for DOI 10.1210/en.2010-0576

    View details for Web of Science ID 000285573000008

    View details for PubMedID 21047945

    View details for PubMedCentralID PMC3033059

  • Three-Dimensional Hemodynamics in the Human Pulmonary Arteries Under Resting and Exercise Conditions ANNALS OF BIOMEDICAL ENGINEERING Tang, B. T., Fonte, T. A., Chan, F. P., Tsao, P. S., Feinstein, J. A., Taylor, C. A. 2011; 39 (1): 347-358

    Abstract

    The biomechanical forces associated with blood flow have been shown to play a role in pulmonary vascular cell health and disease. Therefore, the quantification of human pulmonary artery hemodynamic conditions under resting and exercise states can be useful in investigating the physiology of disease development and treatment outcomes. In this study, a combined magnetic resonance imaging and computational fluid dynamics approach was used to quantify pulsatile flow fields, wall shear stress (WSS), oscillations in WSS (OSI), and energy efficiency in six subject-specific models of the human pulmonary vasculature with high spatial and temporal resolution. Averaging over all subjects, WSS was found to increase from 19.8±4.0 to 51.8±6.7 dynes/cm2, and OSI was found to decrease from 0.094±0.016 to 0.081±0.015 in the proximal pulmonary arteries between rest and exercise conditions (p<0.05). These findings demonstrate the localized, biomechanical effects of exercise. Furthermore, an average decrease of 10% in energy efficiency was noted between rest and exercise. These data indicate the amount of energy dissipation that typically occurs with exercise and may be useful in future surgical planning applications.

    View details for DOI 10.1007/s10439-010-0124-1

    View details for PubMedID 20640512

  • Assessment of Elastase-Induced Murine Abdominal Aortic Aneurysms: Comparison of Ultrasound Imaging with In Situ Video Microscopy JOURNAL OF BIOMEDICINE AND BIOTECHNOLOGY Azuma, J., Maegdefessel, L., Kitagawa, T., Dalman, R. L., McConnell, M. V., Tsao, P. S. 2011

    Abstract

    The aim of this study was to definitively assess the validity of noninvasive high-frequency ultrasound (US) measurements of aortic luminal diameter (ALD) in a murine model of elastase-induced abdominal aortic aneurysm in comparison with in situ video microscopy (VM).C57BL/6 mice underwent transient perfusion of the aorta with either elastase (n = 20: Elastase group) or saline (n = 10: Sham). Unoperated mice (n = 10) were also studied.ALD measurements by US had excellent linear correlation and absolute agreement with that by VM in both Control (unoperated or sham-operated mice) and elastase groups (r = 0.96, intraclass correlation coefficient (ICC) = 0.88 and r = 0.93, ICC = 0.92, resp.). Bland-Altman analysis of US compared with VM measurements in both groups indicated good agreement, however US measurements were slightly but significantly higher than VM measurements in the control group (mean bias 0.039 mm, P < .05). Linear regression analysis revealed excellent correlation between US and VM measurements in both groups. (R² = 0.91 in Control group, R² = 0.85 in elastase group.) The reliability of US measurements was also confirmed by ex vivo histological measurements.High-frequency US provides reliable ALD measurements in developing murine abdominal aortic aneurysms.

    View details for DOI 10.1155/2011/252141

    View details for PubMedID 21331328

  • Chromatin Remodeling Pathways in Smooth Muscle Cell Differentiation, and Evidence for an Integral Role for p300 PLOS ONE Spin, J. M., Quertermous, T., Tsao, P. S. 2010; 5 (12)

    Abstract

    Phenotypic alteration of vascular smooth muscle cells (SMC) in response to injury or inflammation is an essential component of vascular disease. Evidence suggests that this process is dependent on epigenetic regulatory processes. P300, a histone acetyltransferase (HAT), activates crucial muscle-specific promoters in terminal (non-SMC) myocyte differentiation, and may be essential to SMC modulation as well.We performed a subanalysis examining transcriptional time-course microarray data obtained using the A404 model of SMC differentiation. Numerous chromatin remodeling genes (up to 62% of such genes on our array platform) showed significant regulation during differentiation. Members of several chromatin-remodeling families demonstrated involvement, including factors instrumental in histone modification, chromatin assembly-disassembly and DNA silencing, suggesting complex, multi-level systemic epigenetic regulation. Further, trichostatin A, a histone deacetylase inhibitor, accelerated expression of SMC differentiation markers in this model. Ontology analysis indicated a high degree of p300 involvement in SMC differentiation, with 60.7% of the known p300 interactome showing significant expression changes. Knockdown of p300 expression accelerated SMC differentiation in A404 cells and human SMCs, while inhibition of p300 HAT activity blunted SMC differentiation. The results suggest a central but complex role for p300 in SMC phenotypic modulation.Our results support the hypothesis that chromatin remodeling is important for SMC phenotypic switching, and detail wide-ranging involvement of several epigenetic modification families. Additionally, the transcriptional coactivator p300 may be partially degraded during SMC differentiation, leaving an activated subpopulation with increased HAT activity and SMC differentiation-gene specificity.

    View details for DOI 10.1371/journal.pone.0014301

    View details for Web of Science ID 000285246900013

    View details for PubMedID 21179216

    View details for PubMedCentralID PMC3001469

  • Nicotine Accelerates the Expansion of Abdominal Aortic Aneurysms in Mice; A Potential Role for miR-21 and miR-26a Maegdefessel, L., Azuma, J., Spin, J. M., Deng, A., McConnell, M. V., Dalman, R. L., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2010
  • Beneficial Effects of Heme Oxygenase-1 Expression and Activity in Experimental Abdominal Aortic Aneurysm Azuma, J., Wong, R., Maegdefessel, L., Zhao, H., Deng, A., Stevenson, D. K., Tsao, P. S., Kalish, F. S. LIPPINCOTT WILLIAMS & WILKINS. 2010
  • Apelin Inhibits Lipolysis in a Gq-, Gi-, and AMPK-Dependent Manner Yue, P., Jin, H., Aillaud, M., Deng, A., Azuma, J., Kundu, R., Reaven, G., Quertermous, T., Tsao, P. LIPPINCOTT WILLIAMS & WILKINS. 2010
  • Novel 3-Dimensional Microscopy Methodology Development to Study Regional Microstructural Changes over the Time Course of Abdominal Aortic Aneurysm Development Scientific Sessions on Arteriosclerosis, Thrombosis and Vascular Biology Saatchi, S., Azuma, J., Wanchoo, N., Tsao, P. S., Smith, S. J., Yock, P. G., Taylor, C. A. LIPPINCOTT WILLIAMS & WILKINS. 2010: E277–E277
  • Leftward Suprarenal Curvature and Motion in Mice: Possible Influence in the Location and Shape of Angiotensin II-Induced Murine Aneurysms Goergen, C. J., Barr, K. N., Choi, G., Dalman, R. L., Taylor, C. A., Tsao, P. S., Greve, J. M. LIPPINCOTT WILLIAMS & WILKINS. 2010: E272
  • Microarray Analysis Identifies miRNA-26a as a Regulator of Vascular Smooth Muscle Cell Phenotypic Modulation Scientific Sessions on Arteriosclerosis, Thrombosis and Vascular Biology Leeper, N. J., Raiesdana, A., Kojima, Y., Chun, H. J., Azuma, J., Kundu, R. K., Quertermous, T., Tsao, P. S., Spin, J. M. LIPPINCOTT WILLIAMS & WILKINS. 2010: E244–E244
  • In Vivo Quantification of Murine Aortic Cyclic Strain, Motion, and Curvature: Implications for Abdominal Aortic Aneurysm Growth JOURNAL OF MAGNETIC RESONANCE IMAGING Goergen, C. J., Barr, K. N., Huynh, D. T., Eastham-Anderson, J. R., Choi, G., Hedehus, M., Dalman, R. L., Connolly, A. J., Taylor, C. A., Tsao, P. S., Greve, J. M. 2010; 32 (4): 847-858

    Abstract

    To develop methods to quantify cyclic strain, motion, and curvature of the murine abdominal aorta in vivo.C57BL/6J and apoE(-/-) mice underwent three-dimensional (3D) time-of-flight MR angiography to position cardiac-gated 2D slices at four locations along the abdominal aorta where circumferential cyclic strain and lumen centroid motion were calculated. From the 3D data, a centerline through the aorta was created to quantify geometric curvature at 0.1-mm intervals. Medial elastin content was quantified with histology postmortem. The location and shape of abdominal aortic aneurysms (AAAs), created from angiotensin II infusion, were evaluated qualitatively.Strain waveforms were similar at all locations and between groups. Centroid motion was significantly larger and more leftward above the renal vessels than below (P < 0.05). Maximum geometric curvature occurred slightly proximal to the right renal artery. Elastin content was similar around the circumference of the vessel. AAAs developed in the same location as the maximum curvature and grew in the same direction as vessel curvature and motion.The methods presented provide temporally and spatially resolved data quantifying murine aortic motion and curvature in vivo. This noninvasive methodology will allow serial quantification of how these parameters influence the location and direction of AAA growth.

    View details for DOI 10.1002/jmri.22331

    View details for Web of Science ID 000282764800010

    View details for PubMedID 20882615

    View details for PubMedCentralID PMC2975391

  • Differential adipogenic and inflammatory properties of small adipocytes in Zucker Obese and Lean rats DIABETES & VASCULAR DISEASE RESEARCH Liu, A., Sonmez, A., Yee, G., Bazuine, M., Arroyo, M., Sherman, A., McLaughlin, T., Reaven, G., Cushman, S., Tsao, P. 2010; 7 (4): 311-318

    Abstract

    We recently reported that a preponderance of small adipose cells, decreased expression of cell differentiation markers, and enhanced inflammatory activity in human subcutaneous whole adipose tissue were associated with insulin resistance. To test the hypothesis that small adipocytes exhibited these differential properties, we characterised small adipocytes from epididymal adipose tissue of Zucker Obese (ZO) and Lean (ZL) rats. Rat epididymal fat pads were removed and adipocytes isolated by collagenase digestion. Small adipocytes were separated by sequential filtration through nylon meshes. Adipocytes were fixed in osmium tetroxide for cell size distribution analysis via Beckman Coulter Multisizer. Quantitative real-time PCR for cell differentiation and inflammatory genes was performed. Small adipocytes represented a markedly greater percentage of the total adipocyte population in ZO than ZL rats (58±4% vs. 12±3%, p<0.001). In ZO rats, small as compared with total adipocytes had 4-fold decreased adiponectin, and 4-fold increased visfatin and IL-6 levels. Comparison of small adipocytes in ZO versus ZL rats revealed 3-fold decreased adiponectin and PPARγ levels, and 2.5-fold increased IL-6. In conclusion, ZO rat adipose tissue harbours a large proportion of small adipocytes that manifest impaired cell differentiation and pro-inflammatory activity, two mechanisms by which small adipocytes may contribute to insulin resistance.

    View details for DOI 10.1177/1479164110386126

    View details for Web of Science ID 000285080700008

    View details for PubMedID 20961992

    View details for PubMedCentralID PMC3462589

  • Pioglitazone Increases the Proportion of Small Cells in Human Abdominal Subcutaneous Adipose Tissue OBESITY McLaughlin, T. M., Liu, T., Yee, G., Abbasi, F., Lamendola, C., Reaven, G. M., Tsao, P., Cushman, S. W., Sherman, A. 2010; 18 (5): 926-931

    Abstract

    Rodent and in vitro studies suggest that thiazolidinediones promote adipogenesis but there are few studies in humans to corroborate these findings. The purpose of this study was to determine whether pioglitazone stimulates adipogenesis in vivo and whether this process relates to improved insulin sensitivity. To test this hypothesis, 12 overweight/obese nondiabetic, insulin-resistant individuals underwent biopsy of abdominal subcutaneous adipose tissue at baseline and after 12 weeks of pioglitazone treatment. Cell size distribution was determined via the Multisizer technique. Insulin sensitivity was quantified at baseline and postpioglitazone by the modified insulin suppression test. Regional fat depots were quantified by computed tomography (CT). Insulin resistance (steady-state plasma insulin and glucose (SSPG)) decreased following pioglitazone (P < 0.001). There was an increase in the ratio of small-to-large cells (1.16 +/- 0.44 vs. 1.52 +/- 0.66, P = 0.03), as well as a 25% increase in the absolute number of small cells (P = 0.03). The distribution of large cell diameters widened (P = 0.009), but diameter did not increase in the case of small cells. The increase in proportion of small cells was associated with the degree to which insulin resistance improved (r = -0.72, P = 0.012). Visceral abdominal fat decreased (P = 0.04), and subcutaneous abdominal (P = 0.03) and femoral fat (P = 0.004) increased significantly. Changes in fat volume were not associated with SSPG change. These findings demonstrate a clear effect of pioglitazone on human subcutaneous adipose cells, suggestive of adipogenesis in abdominal subcutaneous adipose tissue, as well as redistribution of fat from visceral to subcutaneous depots, highlighting a potential mechanism of action for thiazolidinediones. These findings support the hypothesis that defects in subcutaneous fat storage may underlie obesity-associated insulin resistance.

    View details for DOI 10.1038/oby.2009.380

    View details for Web of Science ID 000277234800013

    View details for PubMedID 19910937

  • Using Pre-existing Microarray Datasets to Increase Experimental Power: Application to Insulin Resistance PLOS COMPUTATIONAL BIOLOGY Daigle, B. J., Deng, A., McLaughlin, T., Cushman, S. W., Cam, M. C., Reaven, G., Tsao, P. S., Altman, R. B. 2010; 6 (3)

    Abstract

    Although they have become a widely used experimental technique for identifying differentially expressed (DE) genes, DNA microarrays are notorious for generating noisy data. A common strategy for mitigating the effects of noise is to perform many experimental replicates. This approach is often costly and sometimes impossible given limited resources; thus, analytical methods are needed which increase accuracy at no additional cost. One inexpensive source of microarray replicates comes from prior work: to date, data from hundreds of thousands of microarray experiments are in the public domain. Although these data assay a wide range of conditions, they cannot be used directly to inform any particular experiment and are thus ignored by most DE gene methods. We present the SVD Augmented Gene expression Analysis Tool (SAGAT), a mathematically principled, data-driven approach for identifying DE genes. SAGAT increases the power of a microarray experiment by using observed coexpression relationships from publicly available microarray datasets to reduce uncertainty in individual genes' expression measurements. We tested the method on three well-replicated human microarray datasets and demonstrate that use of SAGAT increased effective sample sizes by as many as 2.72 arrays. We applied SAGAT to unpublished data from a microarray study investigating transcriptional responses to insulin resistance, resulting in a 50% increase in the number of significant genes detected. We evaluated 11 (58%) of these genes experimentally using qPCR, confirming the directions of expression change for all 11 and statistical significance for three. Use of SAGAT revealed coherent biological changes in three pathways: inflammation, differentiation, and fatty acid synthesis, furthering our molecular understanding of a type 2 diabetes risk factor. We envision SAGAT as a means to maximize the potential for biological discovery from subtle transcriptional responses, and we provide it as a freely available software package that is immediately applicable to any human microarray study.

    View details for DOI 10.1371/journal.pcbi.1000718

    View details for Web of Science ID 000278125200026

    View details for PubMedID 20361040

    View details for PubMedCentralID PMC2845644

  • Inflammation in subcutaneous adipose tissue: relationship to adipose cell size DIABETOLOGIA McLaughlin, T., Deng, A., Yee, G., Lamendola, C., Reaven, G., Tsao, P. S., Cushman, S. W., Sherman, A. 2010; 53 (2): 369-377

    Abstract

    Inflammation is associated with increased body mass and purportedly with increased size of adipose cells. We sought to determine whether increased size of adipose cells is associated with localised inflammation in weight-stable, moderately obese humans.We recruited 49 healthy, moderately obese individuals for quantification of insulin resistance (modified insulin suppression test) and subcutaneous abdominal adipose tissue biopsy. Cell size distribution was analysed with a multisizer device and inflammatory gene expression with real-time PCR. Correlations between inflammatory gene expression and cell size variables, with adjustment for sex and insulin resistance, were calculated.Adipose cells were bimodally distributed, with 47% in a 'large' cell population and the remainder in a 'small' cell population. The median diameter of the large adipose cells was not associated with expression of inflammatory genes. Rather, the fraction of small adipose cells was consistently associated with inflammatory gene expression, independently of sex, insulin resistance and BMI. This association was more pronounced in insulin-resistant than insulin-sensitive individuals. Insulin resistance also independently predicted expression of inflammatory genes.This study demonstrates that among moderately obese, weight-stable individuals an increased proportion of small adipose cells is associated with inflammation in subcutaneous adipose tissue, whereas size of mature adipose cells is not. The observed association between small adipose cells and inflammation may reflect impaired adipogenesis and/or terminal differentiation. However, it is unclear whether this is a cause or consequence of inflammation. This question and whether small vs large adipose cells contribute differently to inflammation in adipose tissue are topics for future research. Trial registration: ClinicalTrials.gov NCT00285844.

    View details for DOI 10.1007/s00125-009-1496-3

    View details for Web of Science ID 000273084400019

    View details for PubMedID 19816674

  • New options with dabigatran etexilate in anticoagulant therapy. Vascular health and risk management Maegdefessel, L., Spin, J. M., Azuma, J., Tsao, P. S. 2010; 6: 339-349

    Abstract

    Thrombosis, the localized clotting of blood, occurs in both the arterial and venous circulation, and has a major impact on health outcomes. The primary etiology of myocardial infarctions, and approximately 80% of strokes, is acute arterial thrombosis. In combination this represents the most common cause of death in the Western world, while the third leading cause of cardiovascular-associated death is venous thromboembolism. An understanding of the pathogenic changes in the vessel wall and the blood that result in thrombosis is crucial for developing safer and more effective antithrombotic drugs. Dabigatran etexilate belongs to a new class of direct thrombin inhibitors. Following oral administration, dabigatran reaches peak plasma concentrations within 2 hours, shows linear pharmacokinetics, and a limited (but important) amount of direct drug interactions. Given once daily at 150 mg or 220 mg, it has proven to be competitive with enoxaparin in the prevention of venous thromboembolism after major orthopedic surgery, with a comparable safety profile. For stroke prevention in patients suffering from atrial fibrillation, dabigatran administered at a dose of 110 mg twice daily was associated with rates of stroke and systemic embolism that were similar to those associated with warfarin, as well as lower rates of hemorrhage. Dabigatran given at a dose of 150 mg twice daily, as compared with warfarin, was associated with lower rates of stroke and systemic embolism but similar rates of major hemorrhage. Oral bioavailability of dabigatran, together with a rapid onset and offset of action and predictable anticoagulation response, makes this newly available antithrombotic drug an attractive alternative to traditional anticoagulant therapies for numerous thrombosis-related indications.

    View details for PubMedID 20531953

  • QUANTIFICATION OF ABDOMINAL AORTIC ANEURYSM DISEASE PROGRESSION USING SMALL ANIMAL MAGNETIC RESONANCE IMAGING 12th ASME Summer Bioengineering Conference Barr, K. N., Goergen, C. J., Hedehus, M., Azuma, J., Taylor, C. A., Tsao, P. S., Greve, J. M. AMER SOC MECHANICAL ENGINEERS. 2010: 659–660
  • Apelin is necessary for the maintenance of insulin sensitivity AMERICAN JOURNAL OF PHYSIOLOGY-ENDOCRINOLOGY AND METABOLISM Yue, P., Jin, H., Aillaud, M., Deng, A. C., Azuma, J., Asagami, T., Kundu, R. K., Reaven, G. M., Quertermous, T., Tsao, P. S. 2010; 298 (1): E59-E67

    Abstract

    The recently discovered peptide apelin is known to be involved in the maintenance of insulin sensitivity. However, questions persist regarding its precise role in the chronic setting. Fasting glucose, insulin, and adiponectin levels were determined on mice with generalized deficiency of apelin (APKO). Additionally, insulin (ITT) and glucose tolerance tests (GTT) were performed. To assess the impact of exogenously delivered apelin on insulin sensitivity, osmotic pumps containing pyroglutamated apelin-13 or saline were implanted in APKO mice for 4 wk. Following the infusion, ITT/GTTs were repeated and the animals euthanized. Soleus muscles were harvested and homogenized in lysis buffer, and insulin-induced Akt phosphorylation was determined by Western blotting. Apelin-13 infusion and ITTs/GTTs were also performed in obese diabetic db/db mice. To probe the underlying mechanism for apelin's effects, apelin-13 was also delivered to cultured C2C12 myotubes. 2-[3H]deoxyglucose uptake and Akt phosphorylation were assessed in the presence of various inhibitors. APKO mice had diminished insulin sensitivity, were hyperinsulinemic, and had decreased adiponectin levels. Soleus lysates had decreased insulin-induced Akt phosphorylation. Administration of apelin to APKO and db/db mice resulted in improved insulin sensitivity. In C2C12 myotubes, apelin increased glucose uptake and Akt phosphorylation. These events were fully abrogated by pertussis toxin, compound C, and siRNA knockdown of AMPKalpha1 but only partially diminished by LY-294002 and not at all by L-NAME. We conclude that apelin is necessary for the maintenance of insulin sensitivity in vivo. Apelin's effects on glucose uptake and Akt phosphorylation are in part mediated by a G(i) and AMPK-dependent pathway.

    View details for DOI 10.1152/ajpendo.00385.2009

    View details for Web of Science ID 000272793700007

    View details for PubMedID 19861585

    View details for PubMedCentralID PMC2806109

  • Modern role for clopidogrel in management of atrial fibrillation and stroke reduction. Vascular health and risk management Maegdefessel, L., Azuma, J., Tsao, P. S. 2010; 6: 95-103

    Abstract

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. The prevalence of AF increases sharply in old age (prevalence approximately 10% among persons 80 years of age and older). The expected risk for ischemic stroke is increased five-fold by the presence of AF, primarily as a result of cardiogenic embolism. Multiple large-scale, randomized trials have been completed or are still underway to find optimal, efficacious, and relatively safe ways to reduce the risk of ischemic stroke and other systemic thromboembolic events related to AF. Antithrombotic strategies are accompanied by serious bleeding complications that threaten patients in need of medical stroke prevention. Treatment regimens for preventing thromboembolism in AF patients range from vitamin K antagonists such as warfarin or coumadins, antiplatelet drugs like aspirin or clopidogrel, to newly developed orally available antithrombotics like the direct thrombin inhibitor dabigatran, or the Factor Xa-inhibitor rivaroxaban. The available anticoagulant and antiplatelet drugs have different advantages and disadvantages. This review attempts to delineate the specific role of clopidogrel in patients with AF and at risk of stroke, taking into consideration new and ongoing trials in this important field of medical practice.

    View details for PubMedID 20234784

  • Distribution of Asymmetric Dimethylarginine among 980 Healthy, Older Adults of Different Ethnicities CLINICAL CHEMISTRY Sydow, K., Fortmann, S. P., Fair, J. M., Varady, A., Hlatky, M. A., Go, A. S., Iribarren, C., Tsao, P. S. 2010; 56 (1): 111-120

    Abstract

    Endothelium-derived nitric oxide plays a crucial role in the regulation of vascular tone and the development of cardiovascular disease. The endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine (ADMA) has emerged as a novel cardiovascular risk factor. ADMA appears to be an independent predictor for cardiovascular and overall mortality. However, the majority of studies investigating the clinical role of ADMA were performed in European study populations with few individuals of other ethnicities.We performed a cross-sectional study of 980 healthy, older (age 60-72 years) individuals of different ethnicities living in the San Francisco Bay area and analyzed ADMA plasma concentrations and their relationship to other cardiovascular risk factors. Plasma ADMA concentrations were measured using a recently developed, highly sensitive ELISA.In our entire sample, we were able to define a reference interval for ADMA plasma concentrations of 0.47 (90% CI 0.46-0.48) mumol/L to 0.85 (0.84-0.89) mumol/L. The mean ADMA concentration was 0.63 (SD 0.11) mumol/L (median 0.61 mumol/L). Mean ADMA concentrations were significantly lower in African Americans (0.60 mumol/L; P < 0.01) and mixed non-Hispanics (0.60 mumol/L; P < 0.05) compared with whites (0.63 mumol/L). ADMA was positively correlated with cystatin-C in both men (rho = 0.29) and women (rho = 0.37), and median plasma ADMA concentrations increased across cystatin-C quintiles.ADMA varies nearly 2-fold across a healthy sample of older men and women, correlates with age, body mass index, and renal function, and is different across ethnic groups. Additional studies in a wider age range and including larger ethnic subgroups would be useful.

    View details for DOI 10.1373/clinchem.2009.136200

    View details for Web of Science ID 000273466300017

    View details for PubMedID 19892843

  • Apelin is Necessary for the Maintenance of Insulin Sensitivity 82nd National Conference and Exhibitions and Scientific Sessions of the American-Heart-Association Yue, P., Jin, H., Aillaud-Manzanera, M., Deng, A. C., Azuma, J., Kundu, R. K., Reaven, G. M., Quertermous, T., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2009: S1114–S1115
  • Generation of Low-antigenicity MHC I Knock-down Human Embryonic Stem Cells Using Molecular Therapy Deuse, T., Seifert, M., Phillips, N., Fire, A., Kay, M., Tsao, P., Reichenspurner, H., Robbins, R. C., Schrepfer, S. LIPPINCOTT WILLIAMS & WILKINS. 2009: S594–S595
  • Differential Intra-abdominal Adipose Tissue Profiling in Obese, Insulin-resistant Women OBESITY SURGERY Liu, A., McLaughlin, T., Liu, T., Sherman, A., Yee, G., Abbasi, F., Lamendola, C., Morton, J., Cushman, S. W., Reaven, G. M., Tsao, P. S. 2009; 19 (11): 1564-1573

    Abstract

    We recently identified differences in abdominal subcutaneous adipose tissue (SAT) from insulin-resistant (IR) as compared to obesity-matched insulin sensitive individuals, including accumulation of small adipose cells, decreased expression of cell differentiation markers, and increased inflammatory activity. This study was initiated to see if these changes in SAT of IR individuals were present in omental visceral adipose tissue (VAT); in this instance, individuals were chosen to be IR but varied in degree of adiposity. We compared cell size distribution and genetic markers in SAT and VAT of IR individuals undergoing bariatric surgery.Eleven obese/morbidly obese women were IR by the insulin suppression test. Adipose tissue surgical samples were fixed in osmium tetroxide for cell size analysis via Beckman Coulter Multisizer. Quantitative real-time polymerase chain reaction for genes related to adipocyte differentiation and inflammation was performed.While proportion of small cells and expression of adipocyte differentiation genes did not differ between depots, inflammatory genes were upregulated in VAT. Diameter of SAT large cells correlated highly with increasing proportion of small cells in both SAT and VAT (r = 0.85, p = 0.001; r = 0.72, p = 0.01, respectively). No associations were observed between VAT large cells and cell size variables in either depot. The effect of body mass index (BMI) on any variables in both depots was negligible.The major differential property of VAT of IR women is increased inflammatory activity, independent of BMI. The association of SAT adipocyte hypertrophy with hyperplasia in both depots suggests a primary role SAT may have in regulating regional fat storage.

    View details for DOI 10.1007/s11695-009-9949-9

    View details for Web of Science ID 000271282900016

    View details for PubMedID 19711137

    View details for PubMedCentralID PMC3181138

  • Hypercholesterolemia impairs exercise capacity in mice VASCULAR MEDICINE Maxwell, A. J., Niebauer, J., Lin, P. S., Tsao, P. S., Bernstein, D., Cooke, J. P. 2009; 14 (3): 249-257

    Abstract

    We previously reported an attenuation of both exercise hyperemia and measures of aerobic capacity in hypercholesterolemic mice. In this study, we expanded upon the previous findings by examining the temporal and quantitative relationship of hypercholesterolemia to aerobic and anaerobic capacity and by exploring several potential mechanisms of dysfunction. Eight-week-old wild type (n = 123) and apoE knockout (n = 79) C57BL/6J mice were divided into groups with distinct cholesterol levels by feeding with regular or high-fat diets. At various ages, the mice underwent treadmill ergospirometry. To explore mechanisms, aortic ring vasodilator function and nitrate (NO(x)) activity, urinary excretion of NO(x), running muscle microvascular density and citrate synthase activity, as well as myocardial mass and histologic evidence of ischemia were measured. At 8 weeks of age, all mice had similar measures of exercise capacity. All indices of aerobic exercise capacity progressively declined at 12 and 20 weeks of age in the hypercholesterolemic mice as cholesterol levels increased while indices of anaerobic capacity remained unaffected. Across the four cholesterol groups, the degree of aerobic dysfunction was related to serum cholesterol levels; a relationship that was maintained after correcting for confounding factors. Associated with the deterioration in exercise capacity was a decline in measures of nitric oxide-mediated vascular function while there was no evidence of aberrations in functional or oxidative capacities or in other components of transport capacity. In conclusion, aerobic exercise dysfunction is observed in murine models of genetic and diet-induced hypercholesterolemia and is associated with a reduction in vascular nitric oxide production.

    View details for DOI 10.1177/1358863X08100040

    View details for Web of Science ID 000268568300008

    View details for PubMedID 19651675

    View details for PubMedCentralID PMC3140166

  • Transcriptional Profiling and Network Analysis of the Murine Angiotensin II-Induced Abdominal Aortic Aneurysm Model Spin, J. M., Hsu, M., Azuma, J., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2009: E112–E113
  • Exercise Delays Progression of Abdominal Aortic Aneurysm Through Anti-inflammatory Gene Expression Hsu, M., Azuma, J., Dalman, R. L., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2009: E61–E62
  • Leftward Abdominal Aortic Motion Correlates with Vessel Bulging in a Murine Aneurysm Model: Possible Role of Biomechanical Forces in Aneurysm Development Goergen, C. J., Hedehus, M., Taylor, C. A., Tsao, P. S., Greve, J. M. LIPPINCOTT WILLIAMS & WILKINS. 2009: E83
  • Mandatory and Voluntary Physical Training Have Analogous Inhibitory Effects on Experimental Abdominal Aortic Aneurysm (AAA) Disease Progression Schultz, G. M., Azuma, J., Hsu, M., Tsao, P., Dalman, R. L. LIPPINCOTT WILLIAMS & WILKINS. 2009: E84
  • Apelin prevents aortic aneurysm formation by inhibiting macrophage inflammation AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY Leeper, N. J., Tedesco, M. M., Kojima, Y., Schultz, G. M., Kundu, R. K., Ashley, E. A., Tsao, P. S., Dalman, R. L., Quertermous, T. 2009; 296 (5): H1329-H1335

    Abstract

    Apelin is a potent inodilator with recently described antiatherogenic properties. We hypothesized that apelin might also attenuate abdominal aortic aneurysm (AAA) formation by limiting disease-related vascular wall inflammation. C57BL/6 mice implanted with osmotic pumps filled with apelin or saline were treated with pancreatic elastase to create infrarenal AAAs. Mice were euthanized for aortic PCR analysis or followed ultrasonographically and then euthanized for histological analysis. The cellular expression of inflammatory cytokines and chemokines in response to apelin was also assessed in cultured macrophages, smooth muscle cells, and fibroblasts. Apelin treatment resulted in diminished AAA formation, with a 47% reduction in maximal cross-sectional area (0.74 vs. 1.39 mm(2), P < 0.03) and a 57% reduction in macrophage infiltrate (113 vs. 261.3 cells/high-power field, P < 0.0001) relative to the saline-treated group. Apelin infusion was also associated with significantly reduced aortic macrophage colony-stimulating factor expression and decreased monocyte chemattractant protein (MCP)-1, macrophage inflammatory protein (MIP)-1alpha, interleukin (IL)-6, and tumor necrosis factor (TNF)-alpha mean mRNA levels. Apelin stimulation of cultured macrophages significantly reduced MCP-1 and TNF-alpha mRNA levels relative to baseline (2.03- and 1.89-fold reduction, P < 0.03, respectively) but did not affect intimal adhesion molecule expression or medial or adventitial cell cytokine production. Apelin significantly reduces aneurysm formation in the elastase model of human AAA disease. The mechanism appears to be decreased macrophage burden, perhaps related to an apelin-mediated decrease in proinflammatory cytokine and chemokine activation.

    View details for DOI 10.1152/ajpheart.01341.2008

    View details for Web of Science ID 000265659100020

    View details for PubMedID 19304942

    View details for PubMedCentralID PMC2685356

  • Creation of murine experimental abdominal aortic aneurysms with elastase. Journal of visualized experiments : JoVE Azuma, J., Asagami, T., Dalman, R., Tsao, P. S. 2009

    Abstract

    Transient intraluminal infusion of porcine pancreatic elastase into the infrarenal segment of the abdominal aorta is the most widely used animal model of abdominal aortic aneurysm (AAA) ever since it was first described in rats by Anidjar and colleagues.(1) The rationale for its development was based on the disrupted nature of elastin observed in AAAs. This rat model has been modified to produce AAAs in the infrarenal aortic region of mice.(2) The model has the ability to add broad insight into the pathobiology of AAA due to the emergence of numerous transgenic and gene knockout mice. Moreover, it is a viable platform to test potential therapeutic agents for AAA. In this video, we demonstrate the elastase infusion AAA procedure used in our laboratory. Mice are anesthetized using 2.5% isoflurane, and a laparotomy is performed under sterile conditions. The abdominal aortais isolated with the assistance of an operating stereomicroscope (Leica). After placing temporary ligatures around the proximal and distal aorta, an aortotomy is created at the bifurcation with the tip of a 30-gauge needle. A heat-tapered segment of PE-10 polyethylene tubing is introduced through the aortotomy and secured. The aortic lumen is subsequently perfused for 5-15 minutes at 100 mm Hg with saline containing type I porcine pancreatic elastase (4.5 U/mL; Sigma Chemical Co.). After removing the perfusion catheter, the aortotomy is repaired without constriction of the lumen.

    View details for DOI 10.3791/1280

    View details for PubMedID 19629030

    View details for PubMedCentralID PMC3148686

  • CORRELATION BETWEEN AORTIC MOTION AND VESSEL BULGING IN A MURINE ANEURYSM MODEL USING SMALL ANIMAL MAGNETIC RESONANCE IMAGING ASME Summer Bioengineering Conference Goergen, C. J., Choi, G., Hedehus, M., Taylor, C. A., Tsao, P. S., Greve, J. M. AMER SOC MECHANICAL ENGINEERS. 2009: 909–910
  • Robust Automatic Feature Extraction for Protein Microarrays 26th IEEE International Instrumentation and Measurement Technology Conference Ahmed, M. O., Dyer, J. S., Hytopoulos, E., Itakura, H., Tsao, P. S. IEEE. 2009: 1721–1726
  • Circulating Markers of Abdominal Aortic Aneurysm Presence and Progression CIRCULATION Golledge, J., Tsao, P. S., Dalman, R. L., Norman, P. E. 2008; 118 (23): 2382-2392
  • Insulin resistance is associated with a modest increase in inflammation in subcutaneous adipose tissue of moderately obese women DIABETOLOGIA McLaughlin, T., Deng, A., Gonzales, O., AILLAUD, M., Yee, G., Lamendola, C., Abbasi, F., Connolly, A. J., Sherman, A., Cushman, S. W., Reaven, G., Tsao, P. S. 2008; 51 (12): 2303-2308

    Abstract

    We have previously described differences in adipose cell size distribution and expression of genes related to adipocyte differentiation in subcutaneous abdominal fat obtained from insulin-sensitive (IS) and -resistant (IR) persons, matched for degree of moderate obesity. To determine whether other biological properties also differ between IR and IS obese individuals, we quantified markers of inflammatory activity in adipose tissue from overweight IR and IS individuals.Subcutaneous abdominal tissue was obtained from moderately obese women, divided into IR (n = 14) and IS (n = 19) subgroups by determining their steady-state plasma glucose (SSPG) concentrations during the insulin suppression test. Inflammatory activity was assessed by comparing expression of nine relevant genes and by immunohistochemical quantification of CD45- and CD68-containing cells.SSPG concentrations were approximately threefold higher in IR than in IS individuals. Expression levels of CD68, EMR1, IL8, IL6 and MCP/CCL2 mRNAs were modestly but significantly increased (p < 0.05) in IR compared with IS participants. Results of immunohistochemical staining were consistent with gene expression data, demonstrating modest differences between IR and IS individuals. Crown-like structures, in which macrophages surround single adipocytes, were rarely seen in tissue from either subgroup.A modest increase in inflammatory activity was seen in subcutaneous adipose tissue from IR compared with equally obese IS individuals. Together with previous evidence of impaired adipose cell differentiation in IR vs equally obese individuals, it appears that at least two biological processes in subcutaneous adipose tissue characterize the insulin-resistant state independent of obesity per se.

    View details for DOI 10.1007/s00125-008-1148-z

    View details for Web of Science ID 000260686000019

    View details for PubMedID 18825363

  • A Human Ferritin Iron Oxide Nano-composite Magnetic Resonance Contrast Agent MAGNETIC RESONANCE IN MEDICINE Uchida, M., Terashima, M., Cunningham, C. H., Suzuki, Y., Willits, D. A., Willis, A. F., Yang, P. C., Tsao, P. S., McConnell, M. V., Young, M. J., Douglas, T. 2008; 60 (5): 1073-1081

    Abstract

    Macrophages play important roles in the immunological defense system, but at the same time they are involved in inflammatory diseases such as atherosclerosis. Therefore, imaging macrophages is critical to assessing the status of these diseases. Toward this goal, a recombinant human H chain ferritin (rHFn)-iron oxide nano composite has been investigated as an MRI contrast agent for labeling macrophages. Iron oxide nanoparticles in the form of magnetite (or maghemite) with narrow size distribution were synthesized in the interior cavity of rHFn. The composite material exhibited the R(2) relaxivity comparable to known iron oxide MRI contrast agents. Furthermore, the mineralized protein cages are readily taken up by macrophages in vitro and provide significant T2* signal loss of the labeled cells. These results encourage further investigation into the development of the rHFn-iron oxide contrast agent to assess inflammatory disease status such as macrophage-rich atherosclerotic plaques in vivo.

    View details for DOI 10.1002/mrm.21761

    View details for Web of Science ID 000260341700008

    View details for PubMedID 18956458

  • Apelin Prevents Aortic Aneurysm Formation by Inhibiting Macrophage Inflammation and Infiltration Leeper, N. J., Tedesco, M. M., Kojima, Y., Schultz, G., Ho, M. Y., Kundu, R. K., Anderson, J. P., Tsao, P. S., Dolman, R. L., Quedermous, T. LIPPINCOTT WILLIAMS & WILKINS. 2008: S451
  • Treatmeant with Rosuvastatin Suppresses the Development of Experimental Abdominal Aortic Aneurysms in Mice by Heme Oxygenase-1 Induction Azuma, J., Wong, R. J., Morisawa, T., Hus, M., Stevenson, D. K., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2008: S1052
  • Apelin signaling antagonizes Ang II effects in mouse models of atherosclerosis JOURNAL OF CLINICAL INVESTIGATION Chun, H. J., Ali, Z. A., Kojima, Y., Kundu, R. K., Sheikh, A. Y., Agrawal, R., Zheng, L., Leeper, N. J., Pearl, N. E., Patterson, A. J., Anderson, J. P., Tsao, P. S., Lenardo, M. J., Ashley, E. A., Quertermous, T. 2008; 118 (10): 3343-3354

    Abstract

    Apelin and its cognate G protein-coupled receptor APJ constitute a signaling pathway with a positive inotropic effect on cardiac function and a vasodepressor function in the systemic circulation. The apelin-APJ pathway appears to have opposing physiological roles to the renin-angiotensin system. Here we investigated whether the apelin-APJ pathway can directly antagonize vascular disease-related Ang II actions. In ApoE-KO mice, exogenous Ang II induced atherosclerosis and abdominal aortic aneurysm formation; we found that coinfusion of apelin abrogated these effects. Similarly, apelin treatment rescued Ang II-mediated increases in neointimal formation and vascular remodeling in a vein graft model. NO has previously been implicated in the vasodepressor function of apelin; we found that apelin treatment increased NO bioavailability in ApoE-KO mice. Furthermore, infusion of an NO synthase inhibitor blocked the apelin-mediated decrease in atherosclerosis and aneurysm formation. In rat primary aortic smooth muscle cells, apelin inhibited Ang II-mediated transcriptional regulation of multiple targets as measured by reporter assays. In addition, we demonstrated by coimmunoprecipitation and fluorescence resonance energy transfer analysis that the Ang II and apelin receptors interacted physically. Taken together, these findings indicate that apelin signaling can block Ang II actions in vascular disease by increasing NO production and inhibiting Ang II cellular signaling.

    View details for DOI 10.1172/JCI34871

    View details for PubMedID 18769630

  • Transcriptome Alteration in the Diabetic Heart by Rosiglitazone: Implications for Cardiovascular Mortality PLOS ONE Wilson, K. D., Li, Z., Wagner, R., Yue, P., Tsao, P., Nestorova, G., Huang, M., Hirschberg, D. L., Yock, P. G., Quertermous, T., Wu, J. C. 2008; 3 (7)

    Abstract

    Recently, the type 2 diabetes medication, rosiglitazone, has come under scrutiny for possibly increasing the risk of cardiac disease and death. To investigate the effects of rosiglitazone on the diabetic heart, we performed cardiac transcriptional profiling and imaging studies of a murine model of type 2 diabetes, the C57BL/KLS-lepr(db)/lepr(db) (db/db) mouse.We compared cardiac gene expression profiles from three groups: untreated db/db mice, db/db mice after rosiglitazone treatment, and non-diabetic db/+ mice. Prior to sacrifice, we also performed cardiac magnetic resonance (CMR) and echocardiography. As expected, overall the db/db gene expression signature was markedly different from control, but to our surprise was not significantly reversed with rosiglitazone. In particular, we have uncovered a number of rosiglitazone modulated genes and pathways that may play a role in the pathophysiology of the increase in cardiac mortality as seen in several recent meta-analyses. Specifically, the cumulative upregulation of (1) a matrix metalloproteinase gene that has previously been implicated in plaque rupture, (2) potassium channel genes involved in membrane potential maintenance and action potential generation, and (3) sphingolipid and ceramide metabolism-related genes, together give cause for concern over rosiglitazone's safety. Lastly, in vivo imaging studies revealed minimal differences between rosiglitazone-treated and untreated db/db mouse hearts, indicating that rosiglitazone's effects on gene expression in the heart do not immediately turn into detectable gross functional changes.This study maps the genomic expression patterns in the hearts of the db/db murine model of diabetes and illustrates the impact of rosiglitazone on these patterns. The db/db gene expression signature was markedly different from control, and was not reversed with rosiglitazone. A smaller number of unique and interesting changes in gene expression were noted with rosiglitazone treatment. Further study of these genes and molecular pathways will provide important insights into the cardiac decompensation associated with both diabetes and rosiglitazone treatment.

    View details for DOI 10.1371/journal.pone.0002609

    View details for Web of Science ID 000264065800015

    View details for PubMedID 18648539

    View details for PubMedCentralID PMC2481284

  • High glucose attenuates the aorta expansion in a mouse model of angiotensin II-induced abdominal aortic aneurysms Asagami, T., Tsao, P. S., Dalman, R. L. LIPPINCOTT WILLIAMS & WILKINS. 2008: E111
  • Asymmetrical dimethylarginine in renal disease: Limits of variation or variation limits? AMERICAN JOURNAL OF NEPHROLOGY Jacobi, J., Tsao, P. S. 2008; 28 (2): 224-237

    Abstract

    Asymmetrical dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, is increasingly recognized as a putative biomarker in cardiovascular and renal disease. Elevated plasma levels of ADMA are the consequence of increased synthesis, reduced renal clearance or reduced enzymatic degradation. Based upon the metabolic fate the highest plasma concentrations of ADMA have been reported in patients with renal failure in whom this molecule accumulates. However, the range of published ADMA levels in patients with chronic renal failure as well as in patients with end-stage renal failure undergoing maintenance hemodialysis, peritoneal dialysis or kidney transplant recipients is widely scattered and overlaps with the levels reported in healthy individuals. This wide distribution can in part be explained by different bioanalytical techniques and the lack of standardization of such assays. This review summarizes available literature on ADMA in patients with kidney disease and stresses the urgent need for a consensus regarding reference values for different analytical methods in order to appreciate the prognostic significance of elevated ADMA levels. At present, one cannot advocate this molecule for risk assessment or individual patient prognosis in the clinical work-up of patients with renal impairment.

    View details for DOI 10.1159/000110092

    View details for Web of Science ID 000251436000007

    View details for PubMedID 17960061

    View details for PubMedCentralID PMC2820345

  • In vivo genetic profiling and cellular localization of apelin reveals a hypoxia-sensitive, endothelial-centered pathway activated in ischemic heart failure AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY Sheikh, A. Y., Chun, H. J., Glassford, A. J., Kundu, R. K., Kutschka, I., Ardigo, D., Hendry, S. L., Wagner, R. A., Chen, M. M., Ali, Z. A., Yue, P., Huynh, D. T., Connolly, A. J., Pelletier, M. P., Tsao, P. S., Robbins, R. C., Quertermous, T. 2008; 294 (1): H88-H98

    Abstract

    Signaling by the peptide ligand apelin and its cognate G protein-coupled receptor APJ has a potent inotropic effect on cardiac contractility and modulates systemic vascular resistance through nitric oxide-dependent signaling. In addition, there is evidence for counterregulation of the angiotensin and vasopressin pathways. Regulatory stimuli of the apelin-APJ pathway are of obvious importance but remain to be elucidated. To better understand the physiological response of apelin-APJ to disease states such as heart failure and to elucidate the mechanism by which such a response might occur, we have used the murine model of left anterior descending coronary artery ligation-induced ischemic cardiac failure. To identify the key cells responsible for modulation and production of apelin in vivo, we have created a novel apelin-lacZ reporter mouse. Data from these studies demonstrate that apelin and APJ are upregulated in the heart and skeletal muscle following myocardial injury and suggest that apelin expression remains restricted to the endothelium. In cardiac failure, endothelial apelin expression correlates with other hypoxia-responsive genes, and in healthy animals both apelin and APJ are markedly upregulated in various tissues following systemic hypoxic exposure. Experiments with cultured endothelial cells in vitro show apelin mRNA and protein levels to be increased by hypoxia, through a hypoxia-inducible factor-mediated pathway. These studies suggest that apelin-expressing endothelial cells respond to conditions associated with heart failure, possibly including local tissue hypoxia, and modulate apelin-APJ expression to regulate cardiovascular homeostasis. The apelin-APJ pathway may thus provide a mechanism for systemic endothelial monitoring of tissue perfusion and adaptive regulation of cardiovascular function.

    View details for DOI 10.1152/ajpheart.00935.2007

    View details for PubMedID 17906101

  • HIF-1 regulates hypoxia- and insulin-induced expression of apelin in adipocytes AMERICAN JOURNAL OF PHYSIOLOGY-ENDOCRINOLOGY AND METABOLISM Glassford, A. J., Yue, P., Sheikh, A. Y., Chun, H. J., Zarafshar, S., Chan, D. A., Reaven, G. M., Quertermous, T., Tsao, P. S. 2007; 293 (6): E1590-E1596

    Abstract

    Apelin, a novel peptide with significant cardioactive properties, is upregulated by insulin in adipocytes. However, the mechanism by which insulin promotes apelin production is unknown. Hypoxia-inducible factor-1 (HIF-1), a heterodimeric transcription factor involved in the angiogenic and metabolic responses to tissue hypoxia, has been shown to be activated by insulin in various settings. We therefore hypothesized that HIF-1 regulates insulin-mediated apelin expression in adipocytes. 3T3-L1 cells were differentiated into adipocytes in culture. For experiments, serum-starved 3T3-L1 cells were exposed to insulin and/or a 1% O(2) environment. Apelin expression was assessed using quantitative real-time PCR and ELISA. To directly assess the role of HIF-1 in apelin production, we differentiated mouse embryonic fibroblasts (MEFs) containing a targeted deletion of the HIF-1alpha gene into adipocytes and measured their response to insulin and hypoxia. Apelin expression in mature 3T3-L1 adipocytes was increased significantly by insulin and was attenuated by pharmacological inhibition of insulin signaling. Exposure of cells to either hypoxia or the chemical HIF activators cobalt chloride (CoCl(2)) and dimethyloxaloylglycine (DMOG) resulted in significant upregulation of apelin, consistent with a role for HIF in apelin induction. Moreover, hypoxia-, CoCl(2)-, DMOG-, and insulin-induced apelin expression were all attenuated in differentiated HIF-1alpha-deficient MEFs. In summary, in cultured 3T3-L1 adipocytes and differentiated MEFs, HIF-1 appears to be involved in hypoxia- and insulin-induced apelin expression.

    View details for DOI 10.1152/ajpendo.00490.2007

    View details for Web of Science ID 000251510200014

    View details for PubMedID 17878221

    View details for PubMedCentralID PMC2570255

  • Circulating chemokines accurately identify individuals with clinically significant atherosclerotic heart disease PHYSIOLOGICAL GENOMICS Ardigo, D., Assimes, T. L., Fortmann, S. P., Go, A. S., Hlatky, M., Hytopoulos, E., Iribarren, C., Tsao, P. S., Tabibiazar, R., Quertermous, T. 2007; 31 (3): 402-409

    Abstract

    Serum inflammatory markers correlate with outcome and response to therapy in subjects with cardiovascular disease. However, current individual markers lack specificity for the diagnosis of coronary artery disease (CAD). We hypothesize that a multimarker proteomic approach measuring serum levels of vascular derived inflammatory biomarkers could reveal a "signature of disease" that can serve as a highly accurate method to assess for the presence of coronary atherosclerosis. We simultaneously measured serum levels of seven chemokines [CXCL10 (IP-10), CCL11 (eotaxin), CCL3 (MIP1 alpha), CCL2 (MCP1), CCL8 (MCP2), CCL7 (MCP3), and CCL13 (MCP4)] in 48 subjects with clinically significant CAD ("cases") and 44 controls from the ADVANCE Study. We applied three classification algorithms to identify the combination of variables that would best predict case-control status and assessed the diagnostic performance of these models with receiver operating characteristic (ROC) curves. The serum levels of six chemokines were significantly higher in cases compared with controls (P < 0.05). All three classification algorithms entered three chemokines in their final model, and only logistic regression selected clinical variables. Logistic regression produced the highest ROC of the three algorithms (AUC = 0.95; SE = 0.03), which was markedly better than the AUC for the logistic regression model of traditional risk factors of CAD without (AUC = 0.67; SE = 0.06) or with CRP (AUC = 0.68; SE = 0.06). A combination of serum levels of multiple chemokines identifies subjects with clinically significant atherosclerotic heart disease with a very high degree of accuracy. These results need to be replicated in larger cross-sectional studies and their prognostic value explored.

    View details for DOI 10.1152/physiolgenomics.00104.2007

    View details for Web of Science ID 000251780600005

    View details for PubMedID 17698927

  • The cardioactive peptide apelin increases adipocyte glucose uptake and is necessary for the maintenance of systemic insulin sensitivity 80th Annual Scientific Session of the American-Heart-Association (AHA) Yue, P., Asagami, T., Kundu, R. K., Yee, Y., Glassford, A. J., Azuma, J., Quertermous, T., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2007: 247–47
  • Small adipocytes: implications for inflammation and insulin resistance Sonmez, A., Sung, K., Yee, G., Deng, A., Mullen, S., McLaughlin, T., Cushman, S., Reaven, G., Tsao, P. OXFORD UNIV PRESS. 2007: 619–619
  • From Zanius to ADMA: ADMA - a new "adipocytokine'' and its potential role in metabolic syndrome JOURNAL OF NEPHROLOGY Kielstein, J. T., Tsao, P. S. 2007; 20 (5): 515–17

    View details for Web of Science ID 000254723800004

    View details for PubMedID 17918135

  • Enhanced proportion of small adipose cells in insulin-resistant vs insulin-sensitive obese individuals implicates impaired adipogenesis DIABETOLOGIA McLaugblin, T., Sherman, A., Tsao, P., Gonzalez, O., Yee, G., Lamendola, C., Reaven, G. M., Cusbman, S. W. 2007; 50 (8): 1707-1715

    Abstract

    The biological mechanism by which obesity predisposes to insulin resistance is unclear. One hypothesis is that larger adipose cells disturb metabolism via increased lipolysis. While studies have demonstrated that cell size increases in proportion to BMI, it has not been clearly shown that adipose cell size, independent of BMI, is associated with insulin resistance. The aim of this study was to test this widely held assumption by comparing adipose cell size distribution in 28 equally obese, otherwise healthy individuals who represented extreme ends of the spectrum of insulin sensitivity, as defined by the modified insulin suppression test.Subcutaneous periumbilical adipose tissue biopsy samples were fixed in osmium tetroxide and passed through the Beckman Coulter Multisizer to obtain cell size distributions. Insulin sensitivity was quantified by the modified insulin suppression test. Quantitative real-time PCR for adipose cell differentiation genes was performed for 11 subjects.All individuals exhibited a bimodal cell size distribution. Contrary to expectations, the mean diameter of the larger cells was not significantly different between the insulin-sensitive and insulin-resistant individuals. Moreover, insulin resistance was associated with a higher ratio of small to large cells (1.66 +/- 1.03 vs 0.94 +/- 0.50, p = 0.01). Similar cell size distributions were observed for isolated adipose cells. The real-time PCR results showed two- to threefold lower expression of genes encoding markers of adipose cell differentiation (peroxisome proliferator-activated receptor gamma1 [PPARgamma1], PPARgamma2, GLUT4, adiponectin, sterol receptor element binding protein 1c) in insulin-resistant compared with insulin-sensitive individuals.These results suggest that after controlling for obesity, insulin resistance is associated with an expanded population of small adipose cells and decreased expression of differentiation markers, suggesting that impairment in adipose cell differentiation may contribute to obesity-associated insulin resistance.

    View details for DOI 10.1007/s00125-007-0708-y

    View details for Web of Science ID 000248225100017

    View details for PubMedID 17549449

  • Asymmetric Dimethyl L-Arginine (ADMA) is a critical regulator of myocardial reperfusion injury CARDIOVASCULAR RESEARCH Stuehlinger, M. C., Conci, E., Haubner, B. J., Stocker, E., Schwaighofer, J., Cooke, J. P., Tsao, P. S., Pachinger, O., Metzler, B. 2007; 75 (2): 417-425

    Abstract

    Endothelial dysfunction by the loss of nitric oxide (NO) is a critical event during reperfusion of ischemic myocardium. Reduced NO availability signals important pathophysiological changes leading to myocardial reperfusion injury. We have recently shown that NO biosynthesis can be disturbed by the endogenous NO synthase (NOS) inhibitor ADMA and that these changes are mediated by an impairment of its metabolism by dimethylarginine dimethylaminohydrolase (DDAH). We therefore analyzed the role of ADMA and its metabolism in the setting of myocardial ischemia and reperfusion.C57-bl6 mice underwent myocardial ischemia for exactly 30 min followed by 2, 4, 8, 12, 24, and 72 h of reperfusion achieved by occlusion and re-opening of the left coronary artery. The reperfused left ventricle was subsequently homogenized for measurements of determinants of the NO synthase pathway. Furthermore, the effects and its mechanisms of ADMA on reperfusion injury were analyzed in a genetic mouse model.A significant accumulation of ADMA was found in myocardial tissue when mice were subjected to 30 min of ischemia followed by reperfusion in our in vivo model. The maximum increase of tissue ADMA at 4 h of reperfusion coincided with reductions of NO tissue concentrations and DDAH activity; protein expression of NOS isoforms, however, was not changed. Furthermore, DDAH overexpression in a genetic mouse model as well as treatment with oral L-arginine markedly reduced reperfusion injury by 40-50% at 4 h of reperfusion. The effects of ADMA on reperfusion injury were shown to be mediated by reduced eNOS activity and phosphorylation, expression of adhesion molecules, and leukocyte activity.Accumulation of tissue ADMA by impairment of DDAH was found to be a significant determinant of reperfusion injury. Our results indicate that ADMA could be a potential new target for the treatment of myocardial ischemia/reperfusion injury.

    View details for DOI 10.1016/j.cardiores.2007.04.030

    View details for Web of Science ID 000248296300022

    View details for PubMedID 17559823

  • Magnetic resonance imaging of progressive cardiomyopathic changes in the db/db mouse AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY Yue, P., Arai, T., Terashima, M., Sheikh, A. Y., Cao, F., Charo, D., Hoyt, G., Robbins, R. C., Ashley, E. A., Wu, J., Yang, P. C., Tsao, P. S. 2007; 292 (5): H2106-H2118

    Abstract

    The db/db mouse is a well-established model of diabetes. Previous reports have documented contractile dysfunction (i.e., cardiomyopathy) in these animals, although the extant literature provides limited insights into cardiac structure and function as they change over time. To better elucidate the natural history of cardiomyopathy in db/db mice, we performed cardiac magnetic resonance (CMR) scans on these animals. CMR imaging was conducted with a 4.7-T magnet on female db/db mice and control db/+ littermates at 5, 9, 13, 17, and 22 wk of age. Gated gradient echo sequences were used to obtain cineographic short-axis slices from apex to base. From these images left ventricular (LV) mass (LVM), wall thickness, end-diastolic volume (LVEDV), and ejection fraction (LVEF) were determined. Additionally, cardiac [(18)F]fluorodeoxyglucose ([(18)F]FDG) PET scanning, pressure-volume loops, and real-time quantitative PCR on db/db myocardium were performed. Relative to control, db/db mice developed significant increases in LVM and wall thickness as early as 9 wk of age. LVEDV diverged slightly later, at 13 wk. Interestingly, compared with the baseline level, LVEF in the db/db group did not decrease significantly until 22 wk. Additionally, [(18)F]FDG metabolic imaging showed a 40% decrease in glucose uptake in db/db mice. Furthermore, contractile dysfunction was observed in 15-wk db/db mice undergoing pressure-volume loops. Finally, real-time quantitative PCR revealed an age-dependent recapitulation of the fetal gene program, consistent with a myopathic process. In summary, as assessed by CMR, db/db mice develop characteristic structural and functional changes consistent with cardiomyopathy.

    View details for DOI 10.1152/ajpheart.00856.2006

    View details for PubMedID 17122193

  • Adiponectin and insulin resistance in young and healthy smokers ENDOCRINE JOURNAL Sonmez, A., Dogru, T., Yilmaz, M. I., Tasci, I., Ocal, R., Ozgurtas, T., Kilic, S., Erbil, K., Erikci, S., Tsao, P. 2006; 53 (6): 729-734

    Abstract

    Smoking is closely associated with insulin resistance, though the mechanism is not clear. Adiponectin, a novel anti-atherosclerotic and anti-inflammatory adipose tissue product, which is closely associated with insulin resistance, was reported to be low in smokers with cofactors for atherosclerosis. However, the effects of smoking on circulating adiponectin levels in otherwise healthy people are unknown. In this study, a case control design was implemented to search for the effect of smoking on plasma adiponectin and insulin sensitivities in healthy people. Sixty-four healthy male smokers, with no family history of hypertension and diabetes mellitus were compared with appropriate 36 age and body mass index matched controls. Both the patients and controls were the soldiers of a troop with regular daily physical activity. Plasma adiponectin, high sensitive C-reactive protein (hsCRP), insulin and lipid levels, and insulin sensitivity as assessed by homeostasis model assessment index (HOMA) of the smokers were measured and compared with those of the controls. The plasma adiponectin, hsCRP, insulin levels and HOMA indexes of the two groups were similar. These parameters were not affected by the amount of cigarettes per day. HDL-cholesterol levels were lower (p = 0.01) and systolic blood pressures were higher (p = 0.02) in the smokers. These results indicate that smoking may not affect plasma adiponectin and insulin levels in young and healthy men with high exercise capacity.

    View details for Web of Science ID 000244725500003

    View details for PubMedID 16960399

  • Smad6 works as a molecular sensor for vascular mechanical stretch Hayashi, S., Matsushita, H., Topper, J. N., Nakashima, S., Ogihara, T., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2006: 323
  • Shear stress quantification and regulation of endothelial cell dysfunction in models of pulmonary arterial hypertension 79th Annual Scientific Session of the American-Heart-Association Tang, B. T., Fonte, T. A., Feinstein, J. A., Taylor, C. A., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2006: 81–81
  • Hypoxia is a primary stimulus for up-regulation of the Apelin-APJ cardio-regulatory pathway Sheikh, A. Y., Chun, H. J., Kundu, R. K., Connolly, A. J., Ardigo, D., Hendry, S. L., Schrepfer, S., Degenfeld, G., Glassford, A. J., Wagner, R. A., Tsao, P. S., Pelletier, M. P., Robbins, R. C., Quertermous, T. LIPPINCOTT WILLIAMS & WILKINS. 2006: 68
  • In vivo bioluminescence imaging of inducible nitric oxide expression in atherosclerosis Terashima, M., Ehara, S., Yang, E., Burns-Guydish, S., Tsao, P. S., Contag, C. H., McConell, M. V. LIPPINCOTT WILLIAMS & WILKINS. 2006: 75
  • Apelin reverses pathologic ventricular remodeling in the db/db obese mouse Yue, P., Ernst, K., Terashima, M., Greve, J. M., Quertermous, T., Yang, P. C., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2006: 174
  • Iron oxide cellular MRI of plaque macrophages has limited in vivo uptake in deep foam cells despite active uptake in vitro 79th Annual Scientific Session of the American-Heart-Association Terashima, M., Ikeda, K., Tsao, P. S., McConnell, M. V. LIPPINCOTT WILLIAMS & WILKINS. 2006: 40–40
  • Abdominal aortic hemodynamics in young healthy adults at rest and during lower limb exercise: quantification using image-based computer modeling AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY Tang, B. T., Cheng, C. P., Draney, M. T., Wilson, N. M., Tsao, P. S., Herfkens, R. J., Taylor, C. A. 2006; 291 (2): H668-H676

    Abstract

    Localization of atherosclerotic lesions in the abdominal aorta has been previously correlated to areas of adverse hemodynamic conditions, such as flow recirculation, low mean wall shear stress, and high temporal oscillations in shear. Along with its many systemic benefits, exercise is also proposed to have local benefits in the vasculature via the alteration of these regional flow patterns. In this work, subject-specific models of the human abdominal aorta were constructed from magnetic resonance angiograms of five young, healthy subjects, and computer simulations were performed under resting and exercise (50% increase in resting heart rate) pulsatile flow conditions. Velocity fields and spatial variations in mean wall shear stress (WSS) and oscillatory shear index (OSI) are presented. When averaged over all subjects, WSS increased from 4.8 +/- 0.6 to 31.6 +/- 5.7 dyn/cm2 and OSI decreased from 0.22 +/- 0.03 to 0.03 +/- 0.02 in the infrarenal aorta between rest and exercise. WSS significantly increased, whereas OSI decreased between rest and exercise at the supraceliac, infrarenal, and suprabifurcation levels, and significant differences in WSS were found between anterior and posterior sections. These results support the hypothesis that exercise provides localized benefits to the cardiovascular system through acute mechanical stimuli that trigger longer-term biological processes leading to protection against the development or progression of atherosclerosis.

    View details for DOI 10.1152/ajpheart.01301.2005

    View details for Web of Science ID 000239020300021

    View details for PubMedID 16603687

  • Molecular signatures determining coronary artery and saphenous vein smooth muscle cell phenotypes - Distinct responses to stimuli ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Deng, D. X., Spin, J. M., Tsalenko, A., Vailaya, A., Ben-Dor, A., Yakhini, Z., Tsao, P., Bruhn, L., Quertermous, T. 2006; 26 (5): 1058-1065

    Abstract

    Phenotypic differences between vascular smooth muscle cell (VSMC) subtypes lead to diverse pathological processes including atherosclerosis, postangioplasty restenosis and vein graft disease. To better understand the molecular mechanisms underlying functional differences among distinct SMC subtypes, we compared gene expression profiles and functional responses to oxidized low-density lipoprotein (OxLDL) and platelet-derived growth factor (PDGF) between cultured SMCs from human coronary artery (CASM) and saphenous vein (SVSM).OxLDL and PDGF elicited markedly different functional responses and expression profiles between the 2 SMC subtypes. In CASM, OxLDL inhibited cell proliferation and migration and modified gene expression of chemokines (CXCL10, CXCL11 and CXCL12), proinflammatory cytokines (IL-1, IL-6, and IL-18), insulin-like growth factor binding proteins (IGFBPs), and both endothelial and smooth muscle marker genes. In SVSM, OxLDL promoted proliferation partially via IGF1 signaling, activated NF-kappaB and phosphatidylinositol signaling pathways, and upregulated prostaglandin (PG) receptors and synthases. In untreated cells, alpha-chemokines, proinflammatory cytokines, and genes associated with apoptosis, inflammation, and lipid biosynthesis were higher in CASM, whereas some beta-chemokines, metalloproteinase inhibitors, and IGFBPs were higher in SVSM. Interestingly, the basal expression levels of these genes seemed closely related to their responses to OxLDL and PDGF. In summary, our results suggest dramatic differences in gene expression patterns and functional responses to OxLDL and PDGF between venous and arterial SMCs, with venous SMCs having stronger proliferative/migratory responses to stimuli but also higher expression of atheroprotective genes at baseline.These results reveal molecular signatures that define the distinct phenotypes characteristics of coronary artery and saphenous vein SMC subtypes.

    View details for DOI 10.1161/01.ATV.0000208185.16371.97

    View details for Web of Science ID 000236942400017

    View details for PubMedID 16456091

  • Plasma asymmetric dimethylarginine concentrations are elevated in obese insulin-resistant women and fall with weight loss JOURNAL OF CLINICAL ENDOCRINOLOGY & METABOLISM McLaughlin, T., Stuhlinger, M., Lamendola, C., Abbasi, F., Bialek, J., Reaven, G. M., Tsao, P. S. 2006; 91 (5): 1896-1900

    Abstract

    Plasma asymmetric dimethylarginine (ADMA) concentrations are higher in apparently healthy, insulin-resistant (IR) individuals and decrease in response to thiazolidenedione treatment.The objective of the study was to determine whether ADMA concentrations would also fall when insulin sensitivity is enhanced with weight loss in obese individuals. DESIGN/SETTING/PATIENTS/INTERVENTION: Twenty obese women classified as IR or insulin sensitive (IS) on the basis of their steady-state plasma glucose (SSPG) concentration during the insulin suppression test underwent 12 wk of dietary weight loss.Plasma glucose, insulin, and ADMA were measured at baseline and after weight loss; change in insulin resistance was quantified by repeating the SSPG after the dietary intervention.Although weight loss was similar in the two groups, significant improvements in SSPG, glucose, and insulin concentrations were confined to the IR group. Baseline plasma ADMA concentrations (mean +/- sd) were higher in IR subjects (1.69 +/- 0.44 vs. 1.18 +/- 0.45 micromol/liter, P = 0.02) and decreased to 1.20 +/- 0.22 micromol/liter (P < 0.001) with weight loss. In contrast, ADMA levels did not change with a similar extent of weight loss in the IS group.Plasma ADMA levels are higher in obese, IR women than in equally obese, IS women and decrease in response to weight loss when associated with enhancement of insulin sensitivity.

    View details for DOI 10.1210/jc.2005-1441

    View details for Web of Science ID 000237330000043

    View details for PubMedID 16507636

  • Proteomic profiles of serum inflammatory markers accurately predict atherosclerosis in mice PHYSIOLOGICAL GENOMICS Tabibiazar, R., Wagner, R. A., Deng, A., Tsao, P. S., Quertermous, T. 2006; 25 (2): 194-202

    Abstract

    At a population level, inflammatory markers have been shown to predict outcome and response to therapy in patients with atherosclerotic cardiovascular disease. However, current markers are not sufficiently sensitive or specific to provide clinical utility for managing individual patients. We hypothesize that measurement of multiple circulating disease-related inflammatory factors will be more informative, allowing the early identification of vascular wall disease activity. We have investigated whether protein microarray-based abundance measurements of circulating proteins can predict the severity of atherosclerotic disease. Using a longitudinal experimental design with apolipoprotein E-deficient mice and control C57Bl/6J and C3H/HeJ wild-type mice, we measured the time-related serum protein expression of 30 inflammatory markers using a protein microarray. We were able to identify a subset of proteins that classify and predict the severity of atherosclerotic disease with a high level of accuracy. The time-specific vascular expression of these markers was verified by showing that their gene expression in the mouse aorta correlated closely to the temporal pattern of serum protein levels. In conclusion, these data suggest that quantification of multiple disease-related inflammatory proteins can provide a more sensitive and specific methodology for assessing atherosclerotic disease activity in humans, and identify candidate biomarkers for such studies.

    View details for DOI 10.1152/physiolgenomics.00240.2005

    View details for Web of Science ID 000236791300002

    View details for PubMedID 16418319

  • Asymmetric dimethyl arginine (ADMA) is associated with incident CAD in older adults Fortmann, S. P., Sydow, K., Fair, J. M., Tsao, P. S., Mahbouba, M., Hlatky, M. A., Iribarren, C., Go, A. S. LIPPINCOTT WILLIAMS & WILKINS. 2006: E339
  • THR0921, a novel peroxisome proliferator-activated receptor gamma agonist, reduces the severity of collagen-induced arthritis ARTHRITIS RESEARCH & THERAPY Tomita, T., Kakiuchi, Y., Tsao, P. S. 2006; 8 (1)

    Abstract

    THR0921 is a novel peroxisome proliferator-activated receptor gamma (PPARgamma) agonist with potent anti-diabetic properties. Because of the proposed role of PPARgamma in inflammation, we investigated the potential of orally active THR0921 to inhibit the pathogenesis of collagen-induced arthritis (CIA). CIA was induced in DBA/1J mice by the injection of bovine type II collagen in complete Freund's adjuvant on days 0 and 21. Mice were treated with THR0921 (50 mg/kg/day) starting on the day of the booster injection and throughout the remaining study period. Both clinical disease activity scores as well as histological scores of joint destruction were significantly reduced in mice treated with THR0921 compared to untreated mice. Proliferation of isolated spleen cells, as well as circulating levels of IgG antibody to type II collagen, was decreased by THR0921. Moreover, spleen cell production of IFN-gamma, tumor necrosis factor (TNF)-alpha and IL-1beta in response to exposure to lipopolysaccharide or type II collagen was reduced by in vivo treatment with THR0921. Steady state mRNA levels of TNF-alpha, IL-1beta, monocyte chemotactic protein-1 and receptor activator of nuclear factor kappaB ligand (RANKL) in isolated joints were all decreased in mice treated with THR0921. Finally, THR0921 inhibited osteoclast differentiation of bone marrow-derived cells stimulated with macrophage colony-stimulating factor and RANKL. In conclusion, THR0921 attenuates collagen-induced arthritis in part by reducing the immune response. As such, PPARgamma may be an important therapeutic target for rheumatoid arthritis.

    View details for DOI 10.1186/ar1856

    View details for Web of Science ID 000235803900016

    View details for PubMedID 16356194

    View details for PubMedCentralID PMC1526548

  • Prolonged cold ischemia in rat cardiac allografts promotes ischemia-reperfusion injury and the development of graft coronary artery disease in a linear fashion JOURNAL OF HEART AND LUNG TRANSPLANTATION Tanaka, M., Mokhtari, G. K., Terry, R. D., Gunawan, F., Balsam, L. B., Hoyt, G., Lee, K. H., Tsao, P. S., Robbins, R. C. 2005; 24 (11): 1906-1914

    Abstract

    Prolonged cold ischemia is thought to exacerbate ischemia-reperfusion injury and graft coronary artery disease (GCAD). We investigated the effect of varying lengths of cold ischemia on inflammation and apoptosis during ischemia-reperfusion injury and correlated this with the degree of GCAD in rat cardiac allografts.PVG rat (RT1c) hearts subjected to 30, 60, 90, 120, or 150 minutes of cold ischemia were heterotopically transplanted into ACI rats (RT1a). Grafts were procured after 4 hours of reperfusion and analyzed for superoxide generation, myeloperoxidase activity, tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and monocyte chemoattractant protein-1/chemokine (C-C motif) ligand 2 (MCP-1/CCL2) production, cardiomyocyte apoptosis, and caspase-2, -3, -8, -9 activities. Additional transplanted animals received cyclosporine A (7.5 mg/kg/day) for 10 days as chronic rejection models. Indices of GCAD were determined at 90 days.A direct linear correlation was found between cold ischemic time, ischemia-reperfusion injury, and GCAD. Superoxide generation, myeloperoxidase activity, TNF-alpha, IL-1beta, MCP-1/CCL2 production, cardiomyocyte apoptosis, and caspase-2, -3, -8, and -9 activities increased with ischemic time, peaking at 120 minutes and plateauing at 150 minutes. GCAD, assessed by the percentage of luminal narrowing, the intima/media ratio, and the percentage of diseased vessels, worsened with increased ischemic time, peaking at 120 minutes and plateauing at 150 minutes. All tested variables in both the acute and chronic phases were significantly increased with 120-minute ischemia compared with 30-minute ischemia.These data indicate that the degree of cardiomyocyte apoptosis and inflammatory response in cardiac allografts during ischemia-reperfusion injury depends on the duration of cold ischemia. More important, that prolonged cold ischemia correlates with increased GCAD.

    View details for DOI 10.1016/j.healun.2004.06.007

    View details for Web of Science ID 000233412300031

    View details for PubMedID 16297799

  • Pathway analysis of coronary atherosclerosis PHYSIOLOGICAL GENOMICS King, J. Y., Ferrara, R., Tabibiazar, R., Spin, J. M., Chen, M. M., Kuchinsky, A., Vailaya, A., Kincaid, R., Tsalenko, A., Deng, D. X., Connolly, A., Zhang, P., Yang, E., Watt, C., Yakhini, Z., Ben-Dor, A., Adler, A., Bruhn, L., Tsao, P., Quertermous, T., Ashley, E. A. 2005; 23 (1): 103-118

    Abstract

    Large-scale gene expression studies provide significant insight into genes differentially regulated in disease processes such as cancer. However, these investigations offer limited understanding of multisystem, multicellular diseases such as atherosclerosis. A systems biology approach that accounts for gene interactions, incorporates nontranscriptionally regulated genes, and integrates prior knowledge offers many advantages. We performed a comprehensive gene level assessment of coronary atherosclerosis using 51 coronary artery segments isolated from the explanted hearts of 22 cardiac transplant patients. After histological grading of vascular segments according to American Heart Association guidelines, isolated RNA was hybridized onto a customized 22-K oligonucleotide microarray, and significance analysis of microarrays and gene ontology analyses were performed to identify significant gene expression profiles. Our studies revealed that loss of differentiated smooth muscle cell gene expression is the primary expression signature of disease progression in atherosclerosis. Furthermore, we provide insight into the severe form of coronary artery disease associated with diabetes, reporting an overabundance of immune and inflammatory signals in diabetics. We present a novel approach to pathway development based on connectivity, determined by language parsing of the published literature, and ranking, determined by the significance of differentially regulated genes in the network. In doing this, we identify highly connected "nexus" genes that are attractive candidates for therapeutic targeting and followup studies. Our use of pathway techniques to study atherosclerosis as an integrated network of gene interactions expands on traditional microarray analysis methods and emphasizes the significant advantages of a systems-based approach to analyzing complex disease.

    View details for DOI 10.1152/physiolgenomics.00101.2005

    View details for Web of Science ID 000232065200012

    View details for PubMedID 15942018

  • Dimethylarginine dimethylaminohydrolase overexpression suppresses graft coronary artery disease CIRCULATION Tanaka, M., Sydow, K., Gunawan, F., Jacobi, J., Tsao, P. S., Robbins, R. C., Cooke, J. P. 2005; 112 (11): 1549-1556

    Abstract

    Graft coronary artery disease (GCAD) is the leading cause of death after the first year of heart transplantation. The reduced bioavailability of endothelium-derived nitric oxide (NO) may play a role in endothelial vasodilator dysfunction and the structural changes that are characteristic of GCAD. A potential contributor to endothelial pathobiology is asymmetric dimethylarginine (ADMA), an endogenous NO synthase inhibitor. We hypothesized that lowering ADMA concentrations by dimethylarginine dimethylaminohydrolase (DDAH) overexpression in the recipient might suppress GCAD and long-term immune responses in murine cardiac allografts.In one series, donor hearts of C-H-2(bm12)KhEg (H-2(bm12)) wild-type (WT) mice were heterotopically transplanted into C57BL/6 (H-2b) transgenic mice overexpressing human DDAH-I or WT littermates and procured after 4 hours of reperfusion (WT and DDAH-I recipients, n=6 each). In a second series, donor hearts were transplanted into DDAH-I-transgenic or WT mice and procured 30 days after transplantation (n=7 each). In DDAH-I recipients, plasma ADMA concentrations were lower, in association with reduced myocardial generation of superoxide anion (WT versus DDAH-I, 465.7+/-79.8 versus 173.4+/-32.3 micromol.L(-1).mg(-1).h(-1); P=0.02), inflammatory cytokines, adhesion molecules, and chemokines. GCAD was markedly reduced in cardiac allografts of DDAH-I-transgenic recipients as assessed by luminal narrowing (WT versus DDAH, 79+/-2% versus 33+/-7%; P<0.01), intima-media ratio (WT versus DDAH, 1.1+/-0.1 versus 0.5+/-0.1; P<0.01), and the percentage of diseased vessels (WT versus DDAH, 100+/-0% versus 62+/-10%; P<0.01).Overexpression of DDAH-I attenuated oxidative stress, inflammatory cytokines, and GCAD in murine cardiac allografts. The effect of DDAH overexpression may be mediated by its reduction of plasma and tissue ADMA concentrations.

    View details for DOI 10.1161/CIRCULATIONAHA.105.537670

    View details for Web of Science ID 000231821200007

    View details for PubMedID 16144995

  • Transforming growth factor-beta receptors localize to caveolae and regulate endothelial nitric oxide synthase in normal human endothelial cells BIOCHEMICAL JOURNAL Schwartz, E. A., Reaven, E., Topper, J. N., Tsao, P. S. 2005; 390: 199-206

    Abstract

    Caveolae (sphingolipid- and cholesterol-rich, 100 nm flask-shaped invaginations of the cell membrane) serve as a nexus of cell signalling. In the present study caveolin-rich lipid raft domains were extracted from HUVEC (human umbilical-vein endothelial cells) using both density gradient and immunoprecipitation techniques, and demonstrated localization of the TGF-beta (transforming growth factor-beta) receptors TbetaRI and TbetaRII to the Cav-1 (caveolin-1)-enriched raft fractions of these normal, human endothelial cells. Immunoprecipitation demonstrated an association between TbetaRI and TbetaRII, as well as an association of the TbetaRs receptors with Cav-1 and eNOS (endothelial nitric oxide synthase), suggesting a mutual co-localization to caveolae; after treatment of HUVEC with 5 ng/ml TGF-beta1 for 15 min, however, co-precipitation of eNOS with TbetaRI, TbetaRII and Cav-1 was diminished. The loss of immunoprecipitable eNOS from Cav-1-enriched fractions was accompanied by a decrease both in phosphorylation of eNOS and in enzymatic activity (conversion of arginine into citrulline). No change in the localization of eNOS to morphologically distinct caveolae could be detected by electron microscopy after treatment of HUVEC with TGF-beta1 for 20 min. The results of these investigations provide evidence that TbetaRI interacts with eNOS in the caveolae of normal, human endothelial cells and has a regulatory function on basal eNOS enzymatic activity.

    View details for DOI 10.1042/BJ20041182

    View details for Web of Science ID 000231492800021

    View details for PubMedID 15819614

    View details for PubMedCentralID PMC1184575

  • Increased aortic stiffness in the insulin-resistant Zucker fa/fa rat AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY Sista, A. K., O'Connell, M. K., Hinohara, T., Oommen, S. S., Fenster, B. E., Glassford, A. J., Schwartz, E. A., Taylor, C. A., Reaven, G. M., Tsao, P. S. 2005; 289 (2): H845-H851

    Abstract

    Accumulating clinical evidence indicates increased aortic stiffness, an independent risk factor for cardiovascular and all-cause mortality, in type 2 diabetic and glucose-intolerant individuals. The present study sought to determine whether increased mechanical stiffness, an altered extracellular matrix, and a profibrotic gene expression profile could be observed in the aorta of the insulin-resistant Zucker fa/fa rat. Mechanical testing of Zucker fa/fa aortas showed increased vascular stiffness in longitudinal and circumferential directions compared with Zucker lean controls. Unequal elevations in developed strain favoring the longitudinal direction resulted in a loss of anisotropy. Real-time quantitative PCR and immunohistochemistry revealed increased expression of fibronectin and collagen IV alpha 3 in the Zucker fa/fa aorta. In addition, expression of transforming growth factor-beta and several Smad proteins was increased in vessels from insulin-resistant animals. In rat vascular smooth muscle cells, 12-18 h of exposure to insulin (100 nmol/l) enhanced transforming growth factor-beta1 mRNA expression, implicating a role for hyperinsulinemia in vascular stiffness. Thus there is mechanical, structural, and molecular evidence of arteriosclerosis in the Zucker fa/fa rat at the glucose-intolerant, hyperinsulinemic stage.

    View details for DOI 10.1152/ajpheart.00134.2005

    View details for Web of Science ID 000230458800045

    View details for PubMedID 15833807

  • Signature patterns of gene expression in mouse atherosclerosis and their correlation to human coronary disease PHYSIOLOGICAL GENOMICS Tabibiazar, R., Wagner, R. A., Ashley, E. A., King, J. Y., Ferrara, R., Spin, J. M., Sanan, D. A., Narasimhan, B., Tibshirani, R., Tsao, P. S., Efron, B., Quertermous, T. 2005; 22 (2): 213-226

    Abstract

    The propensity for developing atherosclerosis is dependent on underlying genetic risk and varies as a function of age and exposure to environmental risk factors. Employing three mouse models with different disease susceptibility, two diets, and a longitudinal experimental design, it was possible to manipulate each of these factors to focus analysis on genes most likely to have a specific disease-related function. To identify differences in longitudinal gene expression patterns of atherosclerosis, we have developed and employed a statistical algorithm that relies on generalized regression and permutation analysis. Comprehensive annotation of the array with ontology and pathway terms has allowed rigorous identification of molecular and biological processes that underlie disease pathophysiology. The repertoire of atherosclerosis-related immunomodulatory genes has been extended, and additional fundamental pathways have been identified. This highly disease-specific group of mouse genes was combined with an extensive human coronary artery data set to identify a shared group of genes differentially regulated among atherosclerotic tissues from different species and different vascular beds. A small core subset of these differentially regulated genes was sufficient to accurately classify various stages of the disease in mouse. The same gene subset was also found to accurately classify human coronary lesion severity. In addition, this classifier gene set was able to distinguish with high accuracy atherectomy specimens from native coronary artery disease vs. those collected from in-stent restenosis lesions, thus identifying molecular differences between these two processes. These studies significantly focus efforts aimed at identifying central gene regulatory pathways that mediate atherosclerotic disease, and the identification of classification gene sets offers unique insights into potential diagnostic and therapeutic strategies in atherosclerotic disease.

    View details for DOI 10.1152/physiolgenomics.00001.2005

    View details for Web of Science ID 000230987900011

    View details for PubMedID 15870398

  • Rosuvastatin attenuates monocyte-endothelial cell interactions and vascular free radical production in hypercholesterolemic mice JOURNAL OF PHARMACOLOGY AND EXPERIMENTAL THERAPEUTICS Li, W., Asagami, T., Matsushita, H., Lee, K. H., Tsao, P. S. 2005; 313 (2): 557-562

    Abstract

    One of the earliest observable events in atherogenesis is enhanced monocyte adhesion to the endothelium. In addition to reducing circulating levels of cholesterol, 3-hydroxy-3-methylglutaryl-CoA reductase inhibitors (statins) are thought to have direct salutary effects upon vascular cells. We hypothesized that the new statin, rosuvastatin, would have anti-inflammatory effects on the vessel wall. Eight-week-old apolipoprotein E-deficient mice were fed a normal chow diet for a period of 12 weeks. During this time mice were administered vehicle or rosuvastatin at a dose of 0, 1, 5, or 20 mg/kg by subcutaneous injection at the same time daily for a period of 2 or 6 weeks prior to sacrifice. At the end of the study, rosuvastatin-treated animals displayed lower plasma total cholesterol levels, whereas showing little change in high-density lipoprotein cholesterol or triglycerides. Using a functional binding assay, we also demonstrated that endothelial adhesiveness for monocytes was significantly attenuated after 2 weeks of treatment with rosuvastatin. Quantitative real-time polymerase chain reaction determined that rosuvastatin reduced the expression of vascular cell adhesion molecule-1, monocyte chemotactic protein-1, and metalloproteinase-9 in the vessel wall. In addition, rosuvastatin inhibited vascular expression of p22(phox) and superoxide production, as well as diminishing plasma 8-isoprostanes concentrations. Thus, treatment with rosuvastatin has acute anti-inflammatory actions that likely participate in its beneficial actions during atherogenesis.

    View details for DOI 10.1124/jpet.104.080002

    View details for PubMedID 15665143

  • Sphingosine-1-phosphate prevents tumor necrosis factor-alpha-mediated monocyte adhesion to aortic endothelium in mice ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Bolick, D. T., Srinivasan, S., Kim, K. W., Hatley, M. E., Clemens, J. J., Whetzel, A., Ferger, N., MACDONALD, T. L., Davis, M. D., Tsao, P. S., Lynch, K. R., Hedrick, C. C. 2005; 25 (5): 976-981

    Abstract

    Endothelial activation and monocyte adhesion to endothelium are key events in inflammation. Sphingosine-1-phosphate (S1P) is a sphingolipid that binds to G protein-coupled receptors on endothelial cells (ECs). We examined the role of S1P in modulating endothelial activation and monocyte-EC interactions in vivo.We injected C57BL/6J mice intravenously with tumor necrosis factor (TNF)-alpha in the presence and absence of the S1P1 receptor agonist SEW2871 and examined monocyte adhesion. Aortas from TNF-alpha-injected mice had a 4-fold increase in the number of monocytes bound, whereas aortas from TNF-alpha plus SEW2871-treated mice had few monocytes bound (P<0.0001). Using siRNA, we found that inhibiting the S1P1 receptor in vascular ECs blocked the ability of S1P to prevent monocyte-EC interactions in response to TNF-alpha. We examined signaling pathways downstream of S1P1 and found that 100 nM S1P increased phosphorylation of Akt and decreased activation of c-jun.Thus, we provide the first evidence that S1P signaling through the endothelial S1P1 receptor protects the vasculature against TNF-alpha-mediated monocyte-EC interactions in vivo.

    View details for DOI 10.1161/01.ATV.0000162171.30089.f6

    View details for Web of Science ID 000228806900373

    View details for PubMedID 15761190

  • Inhibition of heart transplant injury and graft coronary artery disease after prolonged organ ischemia by selective protein kinase C regulators JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY Tanaka, M., Gunawan, F., Terry, R. D., Inagaki, K., Caffarelli, A. D., Hoyt, G., Tsao, P. S., Mochly-Rosen, D., Robbins, R. C. 2005; 129 (5): 1160-1167

    Abstract

    Transplanted hearts subjected to prolonged ischemia develop ischemia-reperfusion injury and graft coronary artery disease. To determine the effect of delta-protein kinase C and -protein kinase C on ischemia-reperfusion injury and the resulting graft coronary artery disease induced by prolonged ischemia, we used a delta-protein kinase C-selective inhibitor peptide and an -protein kinase C-selective activator peptide after 30 or 120 minutes of ischemia.Hearts of piebald viral glaxo (PVG) rats were heterotopically transplanted into allogeneic August Copenhagen Irish (ACI) rats. After cardioplegic arrest of the donor heart, -protein kinase C activator was injected antegrade into the coronary arteries. Hearts were procured and bathed in -protein kinase C activator, and before reperfusion, delta-protein kinase C inhibitor was injected into the recipient inferior vena cava. Controls were treated with saline. To analyze ischemia-reperfusion injury, grafts were procured at 4 hours after transplantation and analyzed for superoxide generation; myeloperoxidase activity; tumor necrosis factor alpha, interleukin 1beta, and monocyte/macrophage chemoattractant protein 1 production; and cardiomyocyte apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling and caspase 2, 3, 8, and 9 activity. To analyze graft coronary artery disease, another set of animals underwent equal ischemic times and treatment strategies and then after 90 days were analyzed for graft coronary artery disease indexes.All measures of ischemia-reperfusion injury and graft coronary artery disease after 120 minutes of ischemia in the saline-treated group were significantly increased relative to those observed after 30 minutes of ischemia. It is important to note that all ischemia-reperfusion injury parameters and graft coronary artery disease indexes decreased significantly in the protein kinase C regulator-treated group in comparison to saline-treated controls; additionally, these values were equivalent to those in saline-treated controls with 30 minutes of ischemia.Combined treatment with -protein kinase C activator and delta-protein kinase C inhibitor reduces ischemia-reperfusion injury and decreases the resulting graft coronary artery disease induced by prolonged ischemia.

    View details for DOI 10.1016/j.jtcvs.2004.09.015

    View details for PubMedID 15867794

  • Mouse strain-specific differences in vascular wall gene expression and their relationship to vascular disease ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Tabibiazar, R., Wagner, R. A., Spin, J. M., Ashley, E. A., Narasimhan, B., Rubin, E. M., Efron, B., Tsao, P. S., Tibshirani, R., Quertermous, T. 2005; 25 (2): 302-308

    Abstract

    Different strains of inbred mice exhibit different susceptibility to the development of atherosclerosis. The C3H/HeJ and C57Bl/6 mice have been used in several studies aimed at understanding the genetic basis of atherosclerosis. Under controlled environmental conditions, variations in susceptibility to atherosclerosis reflect differences in genetic makeup, and these differences must be reflected in gene expression patterns that are temporally related to the development of disease. In this study, we sought to identify the genetic pathways that are differentially activated in the aortas of these mice.We performed genome-wide transcriptional profiling of aortas from C3H/HeJ and C57Bl/6 mice. Differences in gene expression were identified at baseline as well as during normal aging and longitudinal exposure to high-fat diet. The significance of these genes to the development of atherosclerosis was evaluated by observing their temporal pattern of expression in the well-studied apolipoprotein E model of atherosclerosis.Gene expression differences between the 2 strains suggest that aortas of C57Bl/6 mice have a higher genetic propensity to develop inflammation in response to appropriate atherogenic stimuli. This study expands the repertoire of factors in known disease-related signaling pathways and identifies novel candidate genes for future study. To gain insights into the molecular pathways that are differentially activated in strains of mice with varied susceptibility to atherosclerosis, we performed comprehensive transcriptional profiling of their vascular wall. Genes identified through these studies expand the repertoire of factors in disease-related signaling pathways and identify novel candidate genes in atherosclerosis.

    View details for DOI 10.1161/011.ATV.0000151372.86863.a5

    View details for Web of Science ID 000226594000009

    View details for PubMedID 15550693

  • Effect of rosiglitazone treatment on circulating vascular and inflammatory markers in insulin-resistant subjects. Diabetes & vascular disease research Chu, J. W., Abbasi, F., Lamendola, C., McLaughlin, T., Reaven, G. M., Tsao, P. S. 2005; 2 (1): 37-41

    Abstract

    Thiazolidinedione (TZD) compounds enhance insulin sensitivity and attenuate inflammation. The effect of the TZD compound, rosiglitazone (RSG) on both actions was evaluated in two groups of insulin-resistant subjects with minimal elevations of fasting plasma glucose (PG) concentration: group A (n=15, PG < 7.0 mmol/L) and group B (n=14, PG 7.0-8.3 mmol/L). Insulin action, quantified by the insulin suppression test, improved after three months of treatment in both groups, and concentrations of C-reactive protein, plasminogen activator inhibitor-1 and Eselectin all fell. Significant decreases in L-selectin and P-selectin were confined to group B, and concentrations of interleukin-6, intercellular adhesion molecule-1 and vascular cellular adhesion molecule-1 did not fall in either group. Significant relationships were not discerned between enhanced insulin sensitivity and related variables and decreases in inflammatory/vascular markers, suggesting that RSG-induced changes in the latter variables in insulin-resistant individuals might be at least partly independent of the effects of the drug on insulin action.

    View details for PubMedID 16305071

  • Signature pattern of circulating chemokines can improve the identification of coronary artery disease 41st Annual Meeting of the European-Association-for-the-Study-of-Diabetes Ardigo, D., Tabibiazar, R., Olshen, R., Tsao, P. S., Quetermous, T. SPRINGER. 2005: A406–A407
  • Cardiomyocyte-specific Bcl-2 overexpression attenuates ischemia-reperfusion injury, immune response during acute rejection, and graft coronary artery disease BLOOD Tanaka, M., Nakae, S., Terry, P. D., Mokhtari, G. K., Gunawan, F., Balsam, L. B., Kaneda, H., Kofidis, T., Tsao, P. S., Robbins, R. C. 2004; 104 (12): 3789-3796

    Abstract

    After cardiac transplantation, graft damage occurs secondary to ischemia-reperfusion injury and acute rejection. This damage ultimately leads to the development of graft coronary artery disease (GCAD), which limits long-term graft survival. Apoptosis is directly involved in graft injury, contributing to the development of GCAD. To assess the role of the antiapoptotic factor Bcl-2 in the process of GCAD, we transplanted hearts from FVB transgenic mice overexpressing human Bcl-2 under the control of alpha-myosin heavy chain promoter into allogenic C57BL/6 mice. Bcl-2 overexpression led to reduced cytochrome c-mediated caspase-9-dependent cardiomyocyte apoptosis and local inflammation (neutrophil infiltration and proinflammatory cytokine production) in cardiac allografts during ischemia-reperfusion injury and also led to reduced immune responses (inflammatory cell infiltration, production of T(H)1 cytokines and chemokines, and expression of adhesion molecules) during acute and chronic rejection without affecting host CD4(+) and CD8(+) cell responses in the spleen. Thus, local Bcl-2 expression directly contributes to the modulation of local immune responses in allograft rejection, resulting in attenuated GCAD. In conclusion, our findings suggest that the modulation of Bcl-2 expression by pharmacologic up-regulation or gene transfer may be of clinical benefit in the short- and long-term function of cardiac allografts.

    View details for Web of Science ID 000225351600061

    View details for PubMedID 15280201

  • Low flow promotes instent intimal hyperplasia comparison with lumen loss in balloon-injured and uninjured vessels and the effects of the antioxidant pyrrolidine dithiocarbamate ATHEROSCLEROSIS Hanratty, C. G., Murrell, M., Khachigian, L. M., Tsao, P. S., Ward, M. R. 2004; 177 (2): 269-274

    Abstract

    Low flow (LF) promotes late lumen loss after angioplasty by exacerbating inward remodelling through redox-sensitive mechanisms. Stents eliminate inward remodelling and the effect of LF on in-stent restenosis is uncertain. We performed over-sized (1.3-1.5:1) stenting (S) and balloon injury (in the same vessel, B) to the carotid arteries of cholesterol-fed rabbits and compared 28-day late lumen loss with that in an uninjured segment in the same vessel (U). Vessels (n = 5 animals per group) were subjected to high (H), normal (N) and low (L) flow in animals fed either vehicle (V) or the antioxidant pyrrolidine dithiocarbamate, PDTC (P). LF significantly increased in-stent neointima formation relative to normal and high flow (SLV 0.72 +/- 0.07 mm(2) versus SNV 0.43 +/- 0.08 mm(2) versus SHV 0.28 +/- 0.04 mm(2), P < 0.05). However, LF resulted in greater lumen loss in segments from the same vessel subject to balloon injury (lumen SLV 5.18 +/- 0.40 mm(2) and SNV 5.32 +/- 0.40 mm(2) versus BLV 1.28 +/- 0.33 mm(2) and BNV 2.19 +/- 0.28 mm(2)), by greater enhancement of inward remodelling. In addition, inward remodelling and lumen loss due to LF were greater in balloon-injured segments than in adjacent uninjured segments where shear homeostatic remodelling occurs (lumen BLV 1.28 +/- 0.33 mm(2) versus ULV 1.52 +/- 0.22 mm(2)). Lastly, while PDTC effectively reduced intima formation and inward remodelling due to LF in balloon-injured vessels there was no effect on flow-dependent neointima formation in stented vessels. We conclude that LF accentuates in-stent neointima formation, but that flow-dependent lumen loss after stenting is less than that after balloon injury. When LF is present lumen loss can be minimised by antioxidants or stenting.

    View details for DOI 10.1016/j.atherosclerosis.2004.07.016

    View details for Web of Science ID 000225985600006

    View details for PubMedID 15530899

  • Transcriptional profiling of in vitro smooth muscle cell differentiation identifies specific patterns of gene and pathway activation PHYSIOLOGICAL GENOMICS Spin, J. M., Nallamshetty, S., Tabibiazar, R., Ashley, E. A., King, J. Y., Chen, M., Tsao, P. S., Quertermous, T. 2004; 19 (3): 292-302

    Abstract

    Mesodermal and epidermal precursor cells undergo phenotypic changes during differentiation to the smooth muscle cell (SMC) lineage that are relevant to pathophysiological processes in the adult. Molecular mechanisms that underlie lineage determination and terminal differentiation of this cell type have received much attention, but the genetic program that regulates these processes has not been fully defined. Study of SMC differentiation has been facilitated by development of the P19-derived A404 embryonal cell line, which differentiates toward this lineage in the presence of retinoic acid and allows selection for cells adopting a SMC fate through a differentiation-specific drug marker. We sought to define global alterations in gene expression by studying A404 cells during SMC differentiation with oligonucleotide microarray transcriptional profiling. Using an in situ 60-mer array platform with more than 20,000 mouse genes derived from the National Institute on Aging clone set, we identified 2,739 genes that were significantly upregulated after differentiation was completed (false-detection ratio <1). These genes encode numerous markers known to characterize differentiated SMC, as well as many unknown factors. We further characterized the sequential patterns of gene expression during the differentiation time course, particularly for known transcription factor families, providing new insights into the regulation of the differentiation process. Changes in genes associated with specific biological ontology-based pathways were evaluated, and temporal trends were identified for functional pathways. In addition to confirming the utility of the A404 model, our data provide a large-scale perspective of gene regulation during SMC differentiation.

    View details for DOI 10.1152/physiolgenomics.00148.2004

    View details for PubMedID 15340120

  • Overexpression of human copper/zinc superoxide dismutase (SOD1) suppresses ischemia-reperfusion injury and subsequent development of graft coronary artery disease in murine cardiac grafts CIRCULATION Tanaka, M., Mokhtari, G. K., Terry, R. D., Balsam, L. B., Lee, K. H., Kofidis, T., Tsao, P. S., Robbins, R. C. 2004; 110 (11): II200-II206

    Abstract

    Ischemia-reperfusion injury is an important risk factor for graft coronary artery disease (GCAD). We hypothesized that overexpression of SOD1 in donor hearts would suppress ischemia-reperfusion injury and thereby reduce GCAD.In one series, donor hearts of C57BL/6 (H-2b) transgenic mice overexpressing human SOD1 or C57BL/6 wild-type mice were heterotopically transplanted into C57BL/6 recipients and procured after 4 hours of reperfusion (n=6 each). Superoxide, TNF-alpha, and MCP-1/CCL2 production were significantly reduced in the SOD1 transgenic donor heart recipients, and graft injury determined by serum CPK-MB levels was significantly decreased. Cardiomyocyte apoptosis and caspase-3 and caspase-9 activities were significantly decreased in these recipients; caspase-8 activity was unchanged. Fas ligand but not Fas expression was also reduced. In a second series, transgenic and wild-type hearts were transplanted into C-H-2bm12KhEg (H-2bm12) recipients, and then procured on day 56 (n=7 each). Cardiac graft beating was significantly better in the SOD1 transgenic donor heart recipients on days 28, 42, and 56 (but not day 14). Significant reduction in luminal narrowing, the intima/media ratio, and the percentage of diseased vessels was seen in the SOD1 transgenic donor heart recipients, and MCP-1/CCL2, ICAM-1, and VCAM-1 production were significantly reduced.Overexpression of SOD1 attenuates both apoptosis and the inflammatory response during ischemia-reperfusion injury and therefore mitigates against the subsequent development of GCAD.

    View details for DOI 10.1161/01.CIR.0000138390.81640.54

    View details for Web of Science ID 000224023600035

    View details for PubMedID 15364863

  • Long-term effects of polymer-based, slow-release, sirolimus-eluting stents in a porcine coronary model CARDIOVASCULAR RESEARCH Carter, A. J., Aggarwal, M., Kopia, G. A., Tio, F., Tsao, P. S., Kolata, R., Yeung, A. C., Llanos, G., Dooley, L., Falotico, R. 2004; 63 (4): 617-624

    Abstract

    Stent-based delivery of sirolimus (SRL) has shown reduction in neointimal hyperplasia and restenosis. The purpose of this study was to evaluate the chronic vascular response and the expression of cell cycle regulators after SRL-eluting stent implantation in a porcine coronary model.Forty-nine pigs underwent placement of 109 oversized stents (control, n=54, SRL (140 microg/cm(2)), n=55) in the coronary arteries with histologic analysis and Western blot (PCNA, p27(kip1), CD45, MCP-1, IL-2, IL-6, TNF-beta) at 3, 30, 90 or 180 days.At 3 days, the mean thrombus area was similar for control (0.38+/-0.19 mm(2)) and SRL (0.29+/-0.09 mm(2)) stents. After 30 days, the mean neointimal area was significantly less for the SRL (1.40+/-0.35 mm(2)) versus the control stents (2.94+/-1.28 mm(2), p<0.001). At 90 and 180 days, the mean neointimal area was similar for the SRL (3.03+/-0.92 and 3.34+/-0.99 mm(2)) as compared with control stents (3.45+/-1.09 and 3.65+/-1.23 mm(2)). Western blot analysis demonstrated an increased expression of p27(kip1) in the vessel wall at 90 days for the SRL versus control stents (p=0.05) but with increased levels of PCNA in the SRL as compared with control stents (p=0.003).SRL-eluting stents favorably modulate neointimal formation for 30 days in the porcine coronary model. Long-term inhibition of neointimal hyperplasia is not sustained presumably due to delayed cellular proliferation despite increased levels of the cyclin-dependent kinase p27(kip1) in the vessel wall.

    View details for DOI 10.1016/j.cardiores.2004.04.029

    View details for Web of Science ID 000223591400008

    View details for PubMedID 15306217

  • The effect of VEGF-C-induced lymphangiogenesis on gene expression profiles in experimental lymphedema 5th Annual Conference on Arteriosclerosis, Thrombosis, and Vascular Biology Kiazand, A., Tsao, P., An, A. C., Han, J., Swanson, J., Berkowski, A., Karkkainen, M., Alitalo, K., Rockson, S. G. LIPPINCOTT WILLIAMS & WILKINS. 2004: E62–E62
  • The effect of VEGF-C-Induced Lymphangiogenesis on Expression profiles for Lymphangiogenesis-related genes in experimental lymphedema Experimental Biology 2004 Annual Meeting Kiazand, A., Berkowski, J. A., An, A. C., Swanson, J., Han, J., Tsao, P., Alitalo, K., Karkkainen, M., Rockson, S. G. FEDERATION AMER SOC EXP BIOL. 2004: A635–A635
  • Dimethylarginine dimethylaminohydrolase regulates nitric oxide synthesis - Genetic and physiological evidence CIRCULATION Dayoub, H., Achan, V., Adimoolam, S., Jacobi, J., Stuehlinger, M. C., Wang, B. Y., Tsao, P. S., Kimoto, M., Vallance, P., Patterson, A. J., Cooke, J. P. 2003; 108 (24): 3042-3047

    Abstract

    NO is a major regulator of cardiovascular physiology that reduces vascular and cardiac contractility. Accumulating evidence indicates that endogenous inhibitors may regulate NOS. The NOS inhibitors asymmetric dimethylarginine (ADMA) and N-monomethylarginine are metabolized by the enzyme dimethylarginine dimethylaminohydrolase (DDAH). This study was designed to determine if increased expression of DDAH could reduce tissue and plasma levels of the NOS inhibitors and thereby increase NO synthesis.We used gene transfer and transgenic approaches to overexpress human DDAH I in vitro and in vivo. The overexpression of DDAH in cultured endothelial cells in vitro induced a 2-fold increase in NOS activity and NO production. In the hDDAH-1 transgenic mice, we observed approximately 2-fold increases in tissue NOS activity and urinary nitrogen oxides, associated with a 2-fold reduction in plasma ADMA. The systolic blood pressure of transgenic mice was 13 mm Hg lower than that of wild-type controls (P<0.05). The systemic vascular resistance and cardiac contractility were decreased in response to the increase in NO production.DDAH I overexpression increases NOS activity in vitro and in vivo. The hDDAH-1 transgenic animal exhibits a reduced systolic blood pressure, systemic vascular resistance, and cardiac stroke volume. This study provides compelling evidence that the elaboration and metabolism of endogenous ADMA plays an important role in regulation of NOS activity.

    View details for DOI 10.1161/01.CIR.0000101924.04515.2E

    View details for Web of Science ID 000187286300018

    View details for PubMedID 14638548

  • Novel role for the potent endogenous inotrope apelin in human cardiac dysfunction CIRCULATION Chen, M. M., Ashley, E. A., Deng, D. X., Tsalenko, A., Deng, A., Tabibiazar, R., Ben-Dor, A., Fenster, B., Yang, E., King, J. Y., Fowler, M., Robbins, R., Johnson, F. L., Bruhn, L., McDonagh, T., Dargie, H., Yakhini, Z., Tsao, P. S., Quertermous, T. 2003; 108 (12): 1432-1439

    Abstract

    Apelin is among the most potent stimulators of cardiac contractility known. However, no physiological or pathological role for apelin-angiotensin receptor-like 1 (APJ) signaling has ever been described.We performed transcriptional profiling using a spotted cDNA microarray with 12 814 unique clones on paired samples of left ventricle obtained before and after placement of a left ventricular assist device in 11 patients. The significance analysis of microarrays and a novel rank consistency score designed to exploit the paired structure of the data confirmed that natriuretic peptides were among the most significantly downregulated genes after offloading. The most significantly upregulated gene was the G-protein-coupled receptor APJ, the specific receptor for apelin. We demonstrate here using immunoassay and immunohistochemical techniques that apelin is localized primarily in the endothelium of the coronary arteries and is found at a higher concentration in cardiac tissue after mechanical offloading. These findings imply an important paracrine signaling pathway in the heart. We additionally extend the clinical significance of this work by reporting for the first time circulating human apelin levels and demonstrating increases in the plasma level of apelin in patients with left ventricular dysfunction.The apelin-APJ signaling pathway emerges as an important novel mediator of cardiovascular control.

    View details for DOI 10.1161/01.CIR.0000091235.94914.75

    View details for PubMedID 12963638

  • Does glucocorticoid dysregulation contribute to the link between cigarette smoking and insulin resistance? Reply JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Reaven, G. M., Tsao, P. S. 2003; 42 (4): 771–72
  • Endothelial dysfunction: Clinical strategies for treating oxidant stress AMERICAN HEART JOURNAL Fenster, B. E., Tsao, P. S., Rockson, S. G. 2003; 146 (2): 218-226

    Abstract

    A growing body of evidence has demonstrated that oxidants play a critical role in the pathogenesis of endothelial dysfunction. Pathologic processes fundamental to development and progression of endothelial dysfunction such as the oxidation of LDL, the loss of bioavailable nitric oxide, and the vascular inflammatory response are all modulated by oxidant stress. Therapeutic strategies to reverse endothelial dysfunction have begun to focus on agents with the ability to ameliorate oxidant stress.Preclinical and clinical studies evaluating the actions of antioxidants as well as traditional cardiovascular therapies in ameliorating oxidative stress and endothelial dysfunction were reviewed through the use of a MEDLINE search of English language articles published between the years of 1992 and 2002.Antioxidants appear to be an attractive candidate therapy, yet despite compelling preclinical evidence supporting their benefits, efforts to validate the use of vitamins C and E in a clinical setting have been conflicting. In contrast, conventional cardiovascular therapies such as ACE inhibitors, statins, insulin-sensitizing agents, and estrogens have been shown to alleviate endothelial dysfunction, often independent of their effects on systemic disease processes.These agents restore endothelial function through their salutary effects on pathologic vascular oxidative processes.

    View details for DOI 10.1016/S0002-8703(03)00087-X

    View details for PubMedID 12891188

  • NOS inhibition accelerates atherogenesis: reversal by exercise AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY Niebauer, J., Maxwell, A. J., Lin, P. S., Wang, D., Tsao, P. S., Cooke, J. P. 2003; 285 (2): H535-H540

    Abstract

    In this study, we assessed the effects of chronic exercise training (12 wk) on atherosclerotic lesion formation in hypercholesterolemic apolipoprotein E-deficient mice (n = 31). At the age of 9 wk, mice were assigned to the following groups: sedentary (Sed; n = 9); exercise (Ex; n = 12); sedentary and oral NG-nitro-L-arginine (L-NNA, Sed-NA; n = 4), or exercise and oral L-NNA (Ex-NA; n = 6). Chronic exercise training was performed on a treadmill for 12 wk (6 times/wk and twice for 1 h/day) at a final speed of 22 m/min, and an 8 degrees grade. L-NNA was discontinued 5 days before final treadmill testing. The farthest distance run to exhaustion was observed in Ex-NA mice (Sed: 306 +/- 32 m; Ex: 640 +/- 87; Sed-NA: 451 +/- 109 m; Ex-NA: 820 +/- 49 m; all P < 0.05). Lesion formation was assessed in the proximal ascending aorta by dissection microscopy after oil red O staining. The aortas of Sed-NA mice manifested a threefold increase in lesion formation compared with the other groups. This L-NNA-induced lesion formation was reduced by chronic exercise training (Sed, 786 +/- 144; Ex, 780 +/- 206; Sed-NA, 2,147 +/- 522; Ex-NA, 851 +/- 253; Sed-NA vs. all other groups: P < 0.001). In conclusion, treatment with oral L-NNA (an nitric oxide synthase antagonist) leads to accelerated atherogenesis in genetically determined hypercholesterolemic mice. This adverse effect can be overcome by chronic exercise training.

    View details for DOI 10.1152/ajpheart.00360.2001

    View details for PubMedID 12598230

  • Flow-responsive remodeling after angioplasty is enhanced by high cholesterol diet. Prevention with pyrrolidine dithiocarbamate ATHEROSCLEROSIS Ward, M. R., Tsao, P. S., Herity, N. A., Cooke, J. P., Yeung, A. C. 2003; 168 (2): 333-341

    Abstract

    We examined the effects of high cholesterol diet and pyrrolidine dithiocarbamate (PDTC) on flow-dependent remodeling after angioplasty. After right common carotid balloon-injury, the right external carotid (low flow) or left common carotid artery were ligated (high flow) in rabbits fed normal diet, 1% cholesterol diet without or with the antioxidant PDTC for 7 days pre- and 7-28 days post-injury. Angiographic lumen diameter was significantly greater at 28 days in high flow than low flow normal diet animals, attributable on perfusion-fixed vessel morphometry to altered remodeling (area within the external elastic lamina: high flow 1.85+/-0.24 vs. low flow 1.31+/-0.04 mm(2), P<0.05) rather than differences in neointima formation or vessel tone. In animals on 1% cholesterol diet high flow remodeling was significantly enhanced (area within the external elastic lamina 3.13+/-0.17 mm(2), P<0.05 vs. high flow normal diet) but low flow inward remodeling was similar (area within the external elastic lamina 1.29+/-0.07 mm(2)). Mean Doppler flow velocities (initial/post-ligation/28 day follow-up, cm/s) had almost normalized in normal diet animals (high flow 30/49/35, low flow 32/9/26) but showed overcompensation in 1% cholesterol diet animals (high flow 32/49/22, low flow 30/11/25). PDTC therapy markedly attenuated remodeling (area within the external elastic lamina: high flow 2.20+/-0.18, and low flow 2.00+/-0.11 both P<0.05 vs. 1% cholesterol diet alone) and flow velocities only partially normalized (high flow 26/42/34, low flow 27/7/16). We conclude that hypercholesterolemia enhances and PDTC attenuates flow-dependent remodeling after angioplasty.

    View details for DOI 10.1016/S0021-9150(03)00103-5

    View details for Web of Science ID 000183784900016

    View details for PubMedID 12801617

  • Improvements in vascular and inflammatory markers in rosiglitazone treated insulin-resistant subjects are independent of changes in insulin sensitivity or glycemic control Chu, J., Abbasi, F., Lamendola, C., McLaughlin, T., Tsao, P., Reaven, G. AMER DIABETES ASSOC. 2003: A76
  • Identification of endothelial cell genes by combined database mining and microarray analysis PHYSIOLOGICAL GENOMICS Ho, M., Yang, E., Matcuk, G., Deng, D., Sampas, N., Tsalenko, A., Tabibiazar, R., Zhang, Y., Chen, M., Talbi, S., Ho, Y. D., Wang, J., Tsao, P. S., Ben-Dor, A., Yakhini, Z., Bruhn, L., Quertermous, T. 2003; 13 (3): 249-262

    Abstract

    Vascular endothelial cells maintain the interface between the systemic circulation and soft tissues and mediate critical processes such as inflammation in a vascular bed-selective fashion. To expand our understanding of the genetic pathways that underlie these specific functions, we have focused on the identification of novel genes that are differentially expressed in all endothelial cells, as well as restricted groups of this cell type. Virtual subtraction was conducted employing gene expression data deposited in public databases and 384 genes identified. These genes were spotted on custom microarrays, along with 288 genes identified through subtraction cloning from TGF-beta-stimulated endothelial cells. Arrays were evaluated with RNA samples representing endothelial cells cultured from four vascular sources and five non-endothelial cell types. These studies identified 64 pan-endothelial markers that were differentially expressed with at least a threefold difference (range 3- to 55-fold). In addition, differences in gene expression profiles among endothelial cells from different vascular beds were identified. Validation of these findings was performed by RNA blot expression studies, and a number of the novel genes were shown to be expressed under angiogenic conditions in the developing mouse embryo. The combined tools of database mining and transcriptional profiling thus provide expanded knowledge of endothelial cell gene expression and endothelial cell biology.

    View details for DOI 10.1152/physiolgenomics.00186.2002

    View details for Web of Science ID 000182853000008

    View details for PubMedID 12644598

  • Rosuvastatin attenuates the production of vascular reactive oxygen species in ApoE(-/-) mice 4th Annual Conference on Arteriosclerosis Thrombosis and Vascular Biology Asagami, T., Li, W., Lee, K. H., McTaggart, F., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2003: A59–A60
  • The effect of oxidant stress, injury and flow on c-jun and egr-1 expression 4th Annual Conference on Arteriosclerosis Thrombosis and Vascular Biology Murrell, M. J., Khachigian, L. M., Tsao, P., Ward, M. R. LIPPINCOTT WILLIAMS & WILKINS. 2003: A20–A20
  • Lymphangiogenesis in lymphatic insufficiency: Lymphatic endothelial and inflammatory RNA expression patterns 4th Annual Conference on Arteriosclerosis Thrombosis and Vascular Biology Shin, W. S., Rockson, N. B., Sanchez, D. R., Midde, R., Alitalo, K., Karkkainen, M., Tsao, P. S., Rockson, S. G. LIPPINCOTT WILLIAMS & WILKINS. 2003: A52–A52
  • Stent-based immunosuppressive therapies for the prevention of restenosis. Cardiovascular radiation medicine Aggarwal, M., Tsao, P. S., Yeung, A., Carter, A. J. 2003; 4 (2): 98-107

    View details for PubMedID 14581091

  • Insulin resistance and compensatory hyperinsulinemia - The key player between cigarette smoking and cardiovascular disease? JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Reaven, G., Tsao, P. S. 2003; 41 (6): 1044-1047

    Abstract

    Hyperinsulinemia, dyslipidemia, and endothelial dysfunction are characteristic findings in insulin-resistant individuals, and all of these abnormalities have been identified as increasing cardiovascular disease (CVD) risk. Smokers tend to be relatively insulin resistant, hyperinsulinemic, and dyslipidemic, with evidence of endothelial dysfunction, as compared with nonsmokers, and recent epidemiologic data have suggested that CVD in smokers is primarily seen in those individuals who also have the characteristic findings of insulin resistance. Based on these observations, it is argued that insulin resistance and its consequences represent a major mechanistic link between cigarette smoking and CVD. It is also postulated that the enhanced CVD risk in smokers, resulting from hyperinsulinemia, abnormalities of lipoprotein metabolism, and endothelial dysfunction, will primarily be present in those smokers who are insulin resistant. As a corollary, it is suggested that CVD risk in individuals who cannot, or will not, stop smoking can be reduced by therapeutic efforts aimed at attenuating the adverse effects of insulin resistance and its consequences.

    View details for DOI 10.1016/S0735-1097(02)02982-0

    View details for Web of Science ID 000181552800024

    View details for PubMedID 12651055

  • Chronic stent-induced injury and inflammation results in sustained activation of the cell cycle in the porcine model Aggarwal, M., Tsao, P. S., Kopia, G., Glassford, A., Yeung, A. C., Tio, F., Carter, A. J. ELSEVIER SCIENCE INC. 2003: 14A–15A
  • Reduced myocardial brain natriuretic peptide expression and collagen deposition following ventricular assist device support for heart failure 52nd Annual Scientific Session of the American-College-of-Cardiology Fenster, B. E., Fowler, M. B., Yee, Y. G., Connolly, A., Tsao, P. S. ELSEVIER SCIENCE INC. 2003: 165A–165A
  • Short polymers of arginine rapidly translocate into vascular cells - Effects on nitric oxide synthesis CIRCULATION JOURNAL Uemura, S., Rothbard, J. B., Matsushita, H., Tsao, P. S., Fathman, C. G., Cooke, J. P. 2002; 66 (12): 1155-1160

    Abstract

    The present study was designed to determine the efficiency of translocation of short polymers of arginine into vascular smooth muscle cells (VSMC) and to determine their effect on nitric oxide (NO) synthesis. Immunostaining revealed that heptamers of L-arginine (R7) rapidly translocated into the VSMC. This rapid transport was not observed with shorter polymers of L-arginine (R5) nor heptamers of lysine (K7). Translocation of R7 was not inhibited by the addition of free L-arginine into the media. When cells were transiently pretreated with R7 or a nonamer of arginine (R9), NO(2) production from cytokine stimulated VSMC was significantly increased, whereas incubation with R5 and K7 had no effect. Short polymers of arginine not only have a unique ability of rapid VSMC translocation but once internalized enhance NO production. Heptamers (or larger polypeptides) of arginine may be useful in therapy to enhance NO production in the vascular system.

    View details for Web of Science ID 000179496000015

    View details for PubMedID 12499624

  • Flow loading induces macrophage antioxidative gene expression in experimental aneurysms ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Nakahashi, T. K., Hoshina, K., Tsao, P. S., Sho, E., Sho, M., Karwowski, J. K., Yeh, C., Yang, R. B., Topper, J. N., Dalman, R. L. 2002; 22 (12): 2017-2022

    Abstract

    Reactive oxygen species may act as proinflammatory mediators in abdominal aortic aneurysm (AAA) disease. Flow loading increases antioxidative enzyme expression and limits reactive oxygen species production in vascular smooth muscle cells in vitro, limits experimental AAA enlargement in rodent models, and is indirectly associated with reduced clinical AAA risk. We attempted to determine the mechanism or mechanisms by which flow loading limits AAA enlargement.Rodent AAAs were flow loaded via femoral arteriovenous fistula creation. Aortic wall shear stress and relative wall strain were significantly higher in flow-loaded rodents. Flow loading reduced AAA diameter by 26% despite evidence of flow-mediated aortic enlargement proximal to the aneurysmal segment. Messenger RNA from AAA tissue was harvested for cDNA labeling and hybridization to a 384-clone DNA microarray. Twenty-nine genes were differentially expressed (relative intensity/relative intensity of control ratio >1.5 and <0.67) in flow-loaded compared with normal flow AAA tissue, including heme oxygenase 1 (HO-1). Increased HO-1 expression was confirmed via reverse transcriptase-polymerase chain reaction. Immunohistochemistry localized HO-1 expression to infiltrative macrophages. alpha-Tocopherol was found to be as effective as flow loading in limiting AAA enlargement. Flow loading and alpha-tocopherol therapy reduced AAA reactive oxygen species production.Flow loading may attenuate AAA enlargement via wall shear or strain-related reductions in oxidative stress.

    View details for DOI 10.1161/01.ATV.0000042082.38014.EA

    View details for Web of Science ID 000180046000014

    View details for PubMedID 12482828

  • Impaired nitric oxide synthase pathway in diabetes mellitus - Role of asymmetric dimethylarginine and dimethylarginine dimethylaminohydrolase CIRCULATION LIN, K. Y., Ito, A., Asagami, T., Tsao, P. S., Adimoolam, S., Kimoto, M., Tsuji, H., Reaven, G. M., Cooke, J. P. 2002; 106 (8): 987-992

    Abstract

    An endogenous inhibitor of nitric oxide synthase, asymmetric dimethylarginine (ADMA), is elevated in patients with type 2 diabetes mellitus (DM). This study explored the mechanisms by which ADMA becomes elevated in DM.Male Sprague-Dawley rats were fed normal chow or high-fat diet (n=5 in each) with moderate streptozotocin injection to induce type 2 DM. Plasma ADMA was elevated in diabetic rats (1.33+/-0.31 versus 0.48+/-0.08 micromol/L; P<0.05). The activity, but not the expression, of dimethylarginine dimethylaminohydrolase (DDAH) was reduced in diabetic rats and negatively correlated with their plasma ADMA levels (P<0.05). DDAH activity was significantly reduced in vascular smooth muscle cells and human endothelial cells (HMEC-1) exposed to high glucose (25.5 mmol/L). The impairment of DDAH activity in vascular cells was associated with an accumulation of ADMA and a reduction in generation of cGMP. In human endothelial cells, coincubation with the antioxidant polyethylene glycol-conjugated superoxide dismutase (22 U/mL) reversed the effects of the high-glucose condition on DDAH activity, ADMA accumulation, and cGMP synthesis.A glucose-induced impairment of DDAH causes ADMA accumulation and may contribute to endothelial vasodilator dysfunction in DM.

    View details for DOI 10.1161/01.CIR.0000027109.14149.67

    View details for Web of Science ID 000177634600019

    View details for PubMedID 12186805

  • Impaired NOS pathway in diabetes mellitus: role of ADMA and DDAH 24th Annual Scientific Meeting of the European-Society-of-Cardiology (ESC) Lin, K., Tsao, P., Cooke, J. OXFORD UNIV PRESS. 2002: 493–493
  • Metformin treatment lowers asymmetric dimethylarginine concentrations in patients with type 2 diabetes METABOLISM-CLINICAL AND EXPERIMENTAL Asagami, T., Abbasi, F., Stuelinger, M., Lamendola, C., McLaughlin, T., Cooke, J. P., Reaven, G. M., Tsao, P. S. 2002; 51 (7): 843-846

    Abstract

    This study was initiated to see if plasma asymmetric dimethylarginine (ADMA) concentrations decreased in hyperglycemic patients with type 2 diabetes following metformin treatment, either as monotherapy or following its addition to sulfonylurea-treated patients. Fasting plasma glucose, dimethylarginine, and L-arginine concentrations were measured before and 3 months after the administration of a maximally effective dose of metformin to 31 patients with type 2 diabetes in poor glycemic control (fasting plasma concentrations > 9.7 mmol/L), while being treated with either diet (n = 16) or a maximal amount of a sulfonylurea compound (n = 15). Fasting plasma glucose concentration (mean +/- SEM) decreased to a similar degree (P <.01) in patients treated with either metformin alone (12.4 +/- 0.5 to 9.5 +/- 0.5 mmol/L) or when it was added to a sulfonylurea compound (14.1 +/- 0.5 to 10.6 +/- 0.9 mmol/L). The improvement in glycemic control was associated with similar decreases (P <.01) in ADMA concentrations in metformin (1.65 +/- 0.21 to 1.18 +/- 0.13 micromol/L) and sulfonylurea + metformin-treated patients (1.75 +/- 0.13 to 1.19 +/- 0.08 micromol/L). Plasma L-arginine concentrations were similar in the 2 groups at baseline and did not change in response to metformin. Thus, metformin treatment was associated with a favorable increase in the plasma L-arginine/ADMA ratio. These results provide the first evidence that plasma ADMA concentrations decrease in association with improved glycemic control in patients with type 2 diabetes and demonstrate that the magnitude of the change in metformin-treated patients was similar, irrespective of whether it was used as monotherapy or in combination with sulfonylurea treatment.

    View details for DOI 10.1053/meta.2002.33349

    View details for Web of Science ID 000176578200007

    View details for PubMedID 12077728

  • Statin therapy - Beyond cholesterol lowering and antiinflammatory effects CIRCULATION Yeung, A. C., Tsao, P. 2002; 105 (25): 2937-2938
  • Hemodynamic unloading of the left ventricle by ventricular assist devices (VAD) increases angiotensin converting enzyme-1 (ACE) expression in patients with end-stage dilated and ischemic cardiomyopathies Fenster, B. E., Fowler, M. B., Tsao, P. S. FEDERATION AMER SOC EXP BIOL. 2002: A1116
  • Relationship between insulin resistance and an endogenous nitric oxide synthase inhibitor JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION Stuhlinger, M. C., Abbasi, F., Chu, J. W., Lamendola, C., McLaughlin, T. L., Cooke, J. P., Reaven, G. M., Tsao, P. S. 2002; 287 (11): 1420-1426

    Abstract

    Increased levels of asymmetric dimethylarginine (ADMA) are associated with endothelial dysfunction and increased risk of cardiovascular disease. Several cardiovascular risk factors are associated with reduced sensitivity to insulin, but elevated ADMA concentrations have not been fully linked to the metabolic syndrome.To evaluate the relationship between insulin sensitivity and plasma ADMA concentrations, and to determine whether a pharmacological treatment that increases insulin sensitivity would also modulate ADMA concentrations.Cross-sectional study, containing a nonrandomized controlled trial component, of 64 healthy volunteers without diabetes (42 women, 22 men; 48 with normal blood pressure and 16 with hypertension), which was conducted at a university medical center between October 2000 and July 2001.Rosiglitazone (4 mg/d for 4 weeks and then 4 mg twice daily for 8 weeks), an insulin-sensitizing agent, was given to 7 insulin-resistant subjects with hypertension. These subjects were studied before and after 12-week treatment.Insulin sensitivity measured by the insulin suppression test, and fasting plasma levels of low-density lipoprotein cholesterol, triglycerides, high-density lipoprotein cholesterol, glucose, insulin, and ADMA concentrations.Plasma ADMA concentrations were positively correlated with impairment of insulin-mediated glucose disposal in nondiabetic, normotensive subjects (r = 0.73; P<.001). Consistent with the metabolic syndrome, ADMA levels were also positively correlated with fasting triglyceride levels (r = 0.52; P<.001) but not with low-density lipoprotein cholesterol levels (r = 0.19; P =.20). Plasma ADMA concentrations increased in insulin-resistant subjects independent of hypertension. Pharmacological treatment improved insulin sensitivity and reduced mean (SD) plasma ADMA concentrations from 1.50 (0.30) to 1.05 (0.33) micromol/L (P =.001).A significant relationship exists between insulin resistance and plasma concentrations of ADMA. Pharmacological intervention with rosiglitazone enhanced insulin sensitivity and reduced ADMA levels. Increases in plasma ADMA concentrations may contribute to the endothelial dysfunction observed in insulin-resistant patients.

    View details for Web of Science ID 000174465000024

    View details for PubMedID 11903029

  • Elevated glucose increases ADMA: Role of oxidative stress and DDAH Lin, K. Y., Wang, B. Y., Tsao, P. S., Cooke, J. P. ELSEVIER SCIENCE INC. 2002: 251A
  • Homocysteine impairs the nitric oxide synthase pathway - Role of asymmetric dimethylarginine CIRCULATION Stuhlinger, M. C., Tsao, P. S., Her, J. H., Kimoto, M., Balint, R. F., Cooke, J. P. 2001; 104 (21): 2569-2575

    Abstract

    Hyperhomocysteinemia is a putative risk factor for cardiovascular disease, which also impairs endothelium-dependent vasodilatation. A number of other risk factors for cardiovascular disease may exert their adverse vascular effects in part by elevating plasma levels of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase. Accordingly, we determined if homocysteine could increase ADMA levels.When endothelial or nonvascular cells were exposed to DL-homocysteine or to its precursor L-methionine, ADMA concentration in the cell culture medium increased in a dose- and time-dependent fashion. This effect was associated with the reduced activity of dimethylarginine dimethylaminohydrolase (DDAH), the enzyme that degrades ADMA. Furthermore, homocysteine-induced accumulation of ADMA was associated with reduced nitric oxide synthesis by endothelial cells and segments of pig aorta. The antioxidant pyrrollidine dithiocarbamate preserved DDAH activity and reduced ADMA accumulation. Moreover, homocysteine dose-dependently reduced the activity of recombinant human DDAH in a cell free system, an effect that was due to a direct interaction between homocysteine and DDAH.Homocysteine post-translationally inhibits DDAH enzyme activity, causing ADMA to accumulate and inhibit nitric oxide synthesis. This may explain the known effect of homocysteine to impair endothelium-mediated nitric oxide-dependent vasodilatation.

    View details for Web of Science ID 000172307200013

    View details for PubMedID 11714652

  • Plasma concentrations of asymmetric dimethylarginine are increased in patients with type 2 diabetes mellitus AMERICAN JOURNAL OF CARDIOLOGY Abbasi, F., Asagmi, T., Cooke, J. P., Lamendola, C., McLaughlin, T., Reaven, G. M., Stuehlinger, M., Tsao, P. S. 2001; 88 (10): 1201-?

    View details for Web of Science ID 000172412300025

    View details for PubMedID 11703973

  • eNOS activity is reduced in senescent human endothelial cells - Preservation by hTERT immortalization CIRCULATION RESEARCH Matsushita, H., Chang, E., Glassford, A. J., Cooke, J. P., Chiu, C. P., Tsao, P. S. 2001; 89 (9): 793-798

    Abstract

    Advanced age is associated with endothelial dysfunction and increased risk for atherosclerosis. However, the mechanisms for these observed effects are not clear. To clarify the association between aging and loss of endothelial function, young human aortic endothelial cells (HAECs), senescent HAECs transfected with control vector, and immortalized HAECs containing human telomerase reverse transcriptase (hTERT) were compared for expression of endothelial nitric oxide synthase (eNOS) and production of NO. To investigate a specific function modulated by endothelial NO, adhesion of monocytes under basal conditions as well as after exposure to TNF-alpha was assessed. A decrease in eNOS mRNA, protein, and activity was observed in endothelial cells at senescence as compared with young HAEC; this effect was blunted in hTERT cells. In all cells, shear stress induced a greater increase in the expression of eNOS protein with the final result being higher levels in hTERT compared with senescent cells. Basal monocyte binding was significantly elevated on aged endothelial cells compared with parental and hTERT cells. Exposure of TNF-alpha resulted in a 2-fold increase in monocyte adhesion in senescent cells, whereas this effect was reduced in cells transfected with hTERT. Prior exposure to fluid flow significantly reduced subsequent monocyte adhesion in all groups. These studies demonstrate that replicative aging results in decreased endothelial expression of eNOS accompanied by enhanced monocyte binding. Stable expression of hTERT results in endothelial cells with a younger phenotype with greater amount of eNOS and NO activity. Thus, telomerase transfection may have important functional consequences on endothelial cells.

    View details for Web of Science ID 000171974800010

    View details for PubMedID 11679409

  • The novel HMG-CoA reducase inhibitor, Rosuvastatin, attenuates monocyte adhesion in a murine model of hypercholesterolemia Li, W., Asagami, T., McTaggart, F., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2001: 212–12
  • Mechanical stretch modulates TGF-beta/Smad signaling in human vascular cells via down regulation of Smad6 Hayashi, S. I., Matsushita, H., Glassford, A., Li, W., Topper, J. N., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2001: 273–73
  • A novel functional interaction of TGF-beta receptors with eNOS in caveolae Schwartz, E. A., Topper, J. N., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2001: 106–
  • Anti-angiogenic effects of thalidomide characterized by transciptional profiling of endothelial cell-specific gene expression Yang, E., Matcuk, G., Zhang, Y., Talbi, S., Chen, M., Ho, M., Liao, C., Tsao, P. S., Quertermous, T., Deng, D., Sampas, N., Ach, R., Love, W. LIPPINCOTT WILLIAMS & WILKINS. 2001: 123–23
  • Stent-based delivery of sirolimus reduces neointimal formation in a porcine coronary model CIRCULATION Suzuki, T., Kopia, G., Hayashi, S., Bailey, L. R., Llanos, G., Wilensky, R., Klugherz, B. D., Papandreou, G., Narayan, P., Leon, M. B., Yeung, A. C., Tio, F., Tsao, P. S., Falotico, R., Carter, A. J. 2001; 104 (10): 1188-1193

    Abstract

    The purpose of this study was to determine the efficacy of stent-based delivery of sirolimus (SRL) alone or in combination with dexamethasone (DEX) to reduce in-stent neointimal hyperplasia. SRL is a potent immunosuppressive agent that inhibits SMC proliferation by blocking cell cycle progression.Stents were coated with a nonerodable polymer containing 185 microgram SRL, 350 microgram DEX, or 185 microgram SRL and 350 microgram DEX. Polymer biocompatibility studies in the porcine and canine models showed acceptable tissue response at 60 days. Forty-seven stents (metal, n=13; SRL, n=13; DEX, n=13; SRL and DEX, n=8) were implanted in the coronary arteries of 16 pigs. The tissue level of SRL was 97+/-13 ng/artery, with a stent content of 71+/-10 microgram at 3 days. At 7 days, proliferating cell nuclear antigen and retinoblastoma protein expression were reduced 60% and 50%, respectively, by the SRL stents. After 28 days, the mean neointimal area was 2.47+/-1.04 mm(2) for the SRL alone and 2.42+/-1.04 mm(2) for the combination of SRL and DEX compared with the metal (5.06+/-1.88 mm(2), P<0.0001) or DEX-coated stents (4.31+/-3.21 mm(2), P<0.001), resulting in a 50% reduction of percent in-stent stenosis.Stent-based delivery of SRL via a nonerodable polymer matrix is feasible and effectively reduces in-stent neointimal hyperplasia by inhibiting cellular proliferation.

    View details for Web of Science ID 000170922100022

    View details for PubMedID 11535578

  • Cholesterol-induced upregulation of angiotensin II and its effects on monocyte-endothelial interaction and superoxide production VASCULAR MEDICINE Niebauer, J., Tsao, P. S., Lin, P. S., Pratt, R. E., Cooke, J. P. 2001; 6 (3): 133-138

    Abstract

    Atherogenesis involves an early endothelial dysfunction hallmarked by elevated free radical production and increased adhesiveness for monocytes. It was hypothesized that activation of the tissue renin angiotensin system may contribute to the endothelial alteration. To test this hypothesis, thoracic aortae were isolated from normocholesterolemic (NC; n = 6) and hypercholesterolemic (HC; n = 6; diet: 0.5% cholesterol; 6 weeks) New Zealand white rabbits, and incubated for 2 h with the angiotensin II (Ang II) receptor antagonist Sar-1,Ile-8-Ang II, the antioxidant pyrolidine dithiocarbamate (PDTC) and the protein kinase C (PKC) antagonist staurosporin. Superoxide production from aortic segments was measured by lucigenin-enhanced chemiluminescence. In comparison to the normocholesterolemic state, hypercholesterolemia led to a significant increase in superoxide production (221 +/- 44%, p < 0.02); this was reduced by ex vivo treatment of the vessel segment with Ang II-antagonist (to 130 +/- 29%; p < 0.04 vs HC), or PKC-antagonist (to 86 +/- 26%; p < 0.001 vs HC), or PDTC (to 103 +/- 27%; p < 0.02 vs HC). Monocyte-endothelial interaction was assessed by functional binding assay. When compared to normocholesterolemic rabbits, hypercholesterolemia led to a twofold increase in monocyte binding (74 +/- 13 vs 37 +/- 4 monocytoid cells per high power field (m/hpf); p < 0.03). The Ang II-antagonist and the PKC-antagonist led to a normalization of monocyte-endothelial binding (Ang II-antagonist: 37 +/- 9 m/hpf; PKC-antagonist: 41 +/- 17 m/hpf; p < 0.05). In conclusion, these results indicate that hypercholesterolemia activates the tissue renin angiotensin system, which results in an increased endothelial production of superoxide and monocyte adhesiveness. Ang II-antagonist inhibits free radical production and monocyte adhesion through a mechanism which may include PKC.

    View details for Web of Science ID 000172694700002

    View details for PubMedID 11789966

  • Effects of stenting on adjacent vascular distensibility and neointima formation: role of nitric oxide VASCULAR MEDICINE Schwarzacher, S. P., Tsao, P. S., Ward, M., Hayase, M., Niebauer, J., Cooke, J. P., Yeung, A. C. 2001; 6 (3): 139-144

    Abstract

    Intravascular stents increase long-term patency but their effects on the vascular mechanics of adjacent segments have not been studied. In this study, stents were deployed in the rabbit abdominal aorta after 1 week of normal diet, 1% cholesterol diet or 1% cholesterol diet with L-nitro arginine (L-NA 60 mg/l water). Intravascular ultrasound showed a small distal decrease in vessel distensibility (area/pressure * 100) before stenting. Distensibility was almost abolished by stenting (0.12 +/- 0.01, p < 0.001), but was increased proximal to the stent and decreased distal to the stent both acutely (proximal: 1.18 +/- 0.10 vs distal: 0.65 +/- 0.06, p < 0.001), and at 4 weeks (proximal: 1.05 +/- 0.08 vs distal: 0.37 +/- 0.07, p < 0.001). Nitric oxide (NO) activity was enhanced proximal to and within the stent, and remained constant distal to the stent, (versus control, proximal: 57 +/- 23%, stent: 136 +/- 35%, distal: 2 +/- 12%, p < 0.01). The I/M ratio was significantly higher proximal to and within the stent than in the distal segment (proximal: 0.40 +/- 0.10, stent: 0.37 +/- 0.12, distal: 0.12 +/- 0.11, p < 0.01). NO blockade with L-NA prevented hyperdistensibility proximally, and significantly increased the I/M ratio within the stent and distally (stent: 0.81 +/- 0.19, distal: 0.30 +/- 0.10, p < 0.05) but not proximally (0.38 +/- 0.09). In conclusion, aortic stenting increases proximal vascular distensibility and intimal lesion formation. Nitric oxide blockade augments intimal growth within but not proximal to the stent.

    View details for Web of Science ID 000172694700003

    View details for PubMedID 11789967

  • Nicotine stimulates angiogenesis and promotes tumor growth and atherosclerosis NATURE MEDICINE Heeschen, C., Jang, J. J., Weis, M., Pathak, A., Kaji, S., Hu, R. S., Tsao, P. S., Johnson, F. L., Cooke, J. P. 2001; 7 (7): 833-839

    Abstract

    We provide anatomic and functional evidence that nicotine induces angiogenesis. We also show that nicotine accelerates the growth of tumor and atheroma in association with increased neovascularization. Nicotine increased endothelial-cell growth and tube formation in vitro, and accelerated fibrovascular growth in vivo. In a mouse model of hind-limb ischemia, nicotine increased capillary and collateral growth, and enhanced tissue perfusion. In mouse models of lung cancer and atherosclerosis, we found that nicotine enhanced lesion growth in association with an increase in lesion vascularity. These effects of nicotine were mediated through nicotinic acetylcholine receptors at nicotine concentrations that are pathophysiologically relevant. The endothelial production of nitric oxide, prostacyclin and vascular endothelial growth factor might have a role in these effects.

    View details for Web of Science ID 000169808600036

    View details for PubMedID 11433349

  • Diabetes mellitus enhances vascular matrix metalloproteinase activity - Role of oxidative stress CIRCULATION RESEARCH Uemura, S., Matsushita, H., Li, W., Glassford, A. J., Asagami, T., Lee, K. H., Harrison, D. G., Tsao, P. S. 2001; 88 (12): 1291-1298

    Abstract

    Diabetes mellitus (DM) is a primary risk factor for cardiovascular disease. Although recent studies have demonstrated an important role for extracellular matrix metalloproteinases (MMPs) in atherosclerosis, little is known about the effects of hyperglycemia on MMP regulation in vascular cells. Gelatin zymography and Western blot analysis revealed that the activity and expression of 92-kDa (MMP-9) gelatinase, but not of 72 kDa (MMP-2) gelatinase, were significantly increased in vascular tissue and plasma of two distinct rodent models of DM. Bovine aortic endothelial cells (BAECs) grown in culture did not express MMP-9 constitutively; however, chronic (2-week) incubation with high glucose medium induced MMP-9 promoter activity, mRNA and protein expression, and gelatinase activity in BAECs. On the other hand, high glucose culture did not change MMP-9 activity from vascular smooth muscle cells or macrophages. Electron paramagnetic resonance studies indicate that BAECs chronically grown in high glucose conditions produce 70% more ROS than do control cells. Enhanced MMP-9 activity was significantly reduced by treatment with the antioxidants polyethylene glycol-superoxide dismutase and N-acetyl-L-cysteine but not by inhibitors of protein kinase C. In conclusion, vascular MMP-9 activity is increased in DM, in part because of enhanced elaboration from vascular endothelial cells, and oxidative stress plays an important role. This novel mechanism of redox-sensitive MMP-9 expression by hyperglycemia may provide a rationale for antioxidant therapy to modulate diabetic vascular complications.

    View details for Web of Science ID 000169541600013

    View details for PubMedID 11420306

  • Plasma concentrations of asymmetric dimethylagrinine are increased in patients with type 2 diabetes mellitus Abbasi, F., Asagami, T., Cooke, J. P., Lamendola, C., McLaughlin, T., Stuehlinger, M. C., Tsao, P. S., Reaven, G. M. AMER DIABETES ASSOC. 2001: A147–A148
  • Alpha-tocopherol limits experimental aortic aneurysm enlargement YEH, C. C., Nakahashi, T., Hoshina, K., Xu, C. P., Tsao, P., Karwowski, J. K., Dalman, R. L. LIPPINCOTT WILLIAMS & WILKINS. 2001: 638–38
  • Low blood flow after angioplasty augments mechanisms of restenosis - Inward vessel remodeling, cell migration, and activity of genes regulating migration ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Ward, M. R., Tsao, P. S., Agrotis, A., Dilley, R. J., Jennings, G. L., Bobik, A. 2001; 21 (2): 208-213

    Abstract

    -The predominant cause of restenosis after angioplasty is now thought to be inward remodeling, but the mechanisms responsible are unknown. Remodeling in normal vessels is regulated by the endothelium in response to altered shear stress. Although the endothelium is often damaged by angioplasty, restenosis rates after angioplasty have been correlated with impaired coronary flow. Thus, we examined how increases or decreases in blood flow through balloon catheter-injured rat carotid arteries affect vessel morphometry (4, 10, and 28 days), cell migration (4 days), and levels of promigratory mRNAs (2 and 10 days). After 28 days, the luminal area in vessels with low blood flow was significantly less than in those with normal and high blood flow (0.17+/-0.01 [low] versus 0.24+/-0.06 [normal] versus 0.30+/-0.02 [high] mm(2), P:<0.01), predominantly because of accentuated inward remodeling (or reduced area within the external elastic lamina; 0.42+/-0.02 [low] versus 0.54+/-0.07 [normal] versus 0.53+/-0.04 [high] mm(2), P:<0.05). Low flow also enhanced smooth muscle cell migration 4 days after injury by 90% above normal and high flows (P:<0.01). Two days after injury, low flow significantly increased levels of mRNAs encoding promigratory peptides (integrin alpha(v)ss(3), transforming growth factor-ss(1), CD44v6, MDC9, urokinase plasminogen activator receptor, and ss-inducible gene h3); these changes persisted 10 days after injury and were localized to the neointima. Low blood flow may promote restenosis after angioplasty because of its adverse effect on vessel remodeling, and it is associated with the augmented expression of multiple genes central to cell migration and restenosis.

    View details for Web of Science ID 000167563200007

    View details for PubMedID 11156854

  • Endothelial adhesiveness for monocytes is increased by nicotine Chen, H. A., Heeschen, C., Stuehlinger, M., Weis, M., Tsao, P. S., Cooke, J. P. ELSEVIER SCIENCE INC. 2001: 282A
  • Cyclic strain induces reactive oxygen species production via an endothelial NAD(P)H oxidase JOURNAL OF CELLULAR BIOCHEMISTRY Matsushita, H., Lee, K. H., Tsao, P. S. 2001: 99-106

    Abstract

    Vascular endothelial cells are constantly subjected to pressure-induced cyclic strain. Reactive oxygen species (ROS) have been implicated in atherosclerosis and vascular remodeling. Recent evidence indicates that a vascular NAD(P)H oxidase may be an important source of ROS in both physiologic and pathophysiologic situations. The aim of this study was to investigate cyclic strain-induced NAD(P)H oxidase activity in endothelial cells. ROS production was examined by electron paramagnetic resonance and lucigenin chemiluminescence. Cyclic strain-induced NAD(P)H oxidase activity was quantified by activity assay while the expression of p22phox was monitored by Northern blotting. Endothelial cells produce basal amounts of ROS that were enhanced by cyclic strain. Moreover subsequent stimulation with TNF-alpha resulted in significantly greater ROS production in cells previously exposed to cyclic strain as compared to static conditions. Cyclic strain resulted in a significant increase in message for the p22phox subunit as well as activity of the NAD(P)H oxidase. The induced oxidative stress was accompanied by increased mobilization of the transcription factor NFkappaB, an effect that was blocked by a pharmacological inhibitor of NAD(P)H. These results demonstrate a pivotal role for NAD(P)H oxidase in cyclic strain-induced endothelial ROS production and may provide insight into the modulation of vascular disease by biomechanical forces. J. Cell. Biochem. Suppl. 36: 99-106, 2001.

    View details for Web of Science ID 000168543400011

    View details for PubMedID 11455575

  • Mechanotransduction of endothelial oxidative stress induced by cyclic strain ENDOTHELIUM-JOURNAL OF ENDOTHELIAL CELL RESEARCH Wang, D. S., Proffit, D., Tsao, P. S. 2001; 8 (4): 283-291

    Abstract

    Atherosclerotic lesions display a nonuniform distribution throughout the vascular tree. Mechanical forces produced by local alterations in blood flow may play an important role in the localization of atherosclerosis. One such force, cyclic strain, has been hypothesized to promote atherogenesis by inducing oxidative stress in endothelial cells, resulting in enhanced endothelial adhesiveness for monocytes. To investigate the signal transduction systems involved, human aortic endothelial cells were plated on flexible silicone strips that were either non-coated or adsorbed with poly-L-lysine, vitronectin, fibronectin, or collagen I. Cells were then subjected to uniform sinusoidal stretch (10%) for 6 h. Endothelial superoxide anion production was increased in cells exposed to cyclic strain compared to static conditions. Furthermore, endothelial oxidative response to stretch was matrix protein-dependent, whereas cells grown on fibronectin and collagen I produced significantly more superoxide. The oxidative response to cyclic strain was reduced by coincubation with RGD peptides, blocking antibodies to alpha2- and beta-integrins antibodies, as well as inhibitors of protein kinase C. To investigate the effect of oxidative stress on gene transcription, endothelial cells grown on collagen I were transfected with an NFkappaB-sensitive luciferase construct. Cells that underwent cyclic strain displayed a tenfold induction of NFkappaB activation compared to static controls. Strain-induced luciferase activity was blunted by coincubation with RGD peptides or calphostin C. Thus, exposure of endothelial cells to cyclic strain led to integrin activation of a PKC-sensitive pathway that results in increased superoxide anion production and mobilization of NFkappaB.

    View details for Web of Science ID 000173063400007

    View details for PubMedID 11824481

  • An endogenous inhibitor of nitric oxide synthase regulates endothelial adhesiveness for monocytes JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Boger, R. H., Bode-Boger, S. M., Tsao, P. S., Lin, P. S., Chan, J. R., Cooke, J. P. 2000; 36 (7): 2287-2295

    Abstract

    We sought to determine whether asymmetric dimethylarginine (ADMA) inhibits nitric oxide (NO) elaboration in cultured human endothelial cells and whether this is associated with the activation of oxidant-sensitive signaling mediating endothelial adhesiveness for monocytes.Endothelial NO elaboration is impaired in hypercholesterolemia and atherosclerosis, which may be due to elevated concentrations of ADMA, an endogenous inhibitor of NO synthase.Human umbilical vein endothelial cells (ECV 304) and human monocytoid cells (THP-1) were studied in a functional binding assay. Nitric oxide and superoxide anion (O2-) were measured by chemiluminescence; ADMA by high pressure liquid chromatography; monocyte chemotactic protein-1 (MCP-1) by ELISA and NF-KB by electromobility gel shift assay.Incubation of endothelial cells with ADMA (0.1 microM to 100 microM) inhibited NO formation, which was reversed by coincubation with L-arginine (1 mM). The biologically inactive stereoisomer symmetric dimethylarginine did not inhibit NO release. Asymmetric dimethylarginine (10 microM) or native low-density lipoprotein cholesterol (100 mg/dL) increased endothelial O2- to the same degree. Asymmetric dimethylarginine also stimulated MCP-1 formation by endothelial cells. This effect was paralleled by activation of the redox-sensitive transcription factor NF-KB. Preincubation of endothelial cells with ADMA increased the adhesiveness of endothelial cells for THP-1 cells in a concentration-dependent manner. Asymmetric dimethylarginine-induced monocyte binding was diminished by L-arginine or by a neutralizing anti-MCP-1 antibody.We concluded that the endogenous NO synthase inhibitor ADMA is synthesized in human endothelial cells. Asymmetric dimethylarginine increases endothelial oxidative stress and potentiates monocyte binding. Asymmetric dimethylarginine may be an endogenous proatherogenic molecule.

    View details for Web of Science ID 000165600400041

    View details for PubMedID 11127475

  • Hyperglycemia induces matrix metalloproteinase activity in vascular cells: Role of oxidative stress Uemura, S., Matsushita, H. S., Asagami, T. K., Li, W., Lee, K. H., Tsao, P. S. LIPPINCOTT WILLIAMS & WILKINS. 2000: 174–74
  • Metformin attenuates plasma asymmetric dimethylarginine and monocyte adhesion in type 2 diabetes Asagami, T., Stuehlinger, M. C., Li, W., Abbasi, F. A., Tsao, P. S., Cooke, J. P., Reaven, G. M. LIPPINCOTT WILLIAMS & WILKINS. 2000: 232–32
  • Regulated expression of endothelial cell-derived lipase BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS Hirata, K., Ishida, T., Matsushita, H., Tsao, P. S., Quertermous, T. 2000; 272 (1): 90-93

    Abstract

    A lipoprotein lipase-like gene was recently cloned from endothelial cells. In vitro functional experiments have suggested that this endothelial-derived lipase (EDL) has phospholipase activity, and preliminary in vivo studies have suggested a role in the regulation of high-density lipoprotein metabolism. To investigate local control of lipase activity and lipid metabolism in the blood vessel wall, we have examined the regulation of EDL expression in cultured human umbilical vein and coronary artery endothelial cells. EDL mRNA levels were upregulated in both cell types by inflammatory cytokines implicated in vascular disease etiology, including TNF-alpha and IL-1beta. In addition, both fluid shear stress and cyclic stretch were found to increase the EDL mRNA levels in these cultured cells. This highly regulated expression of EDL in vascular endothelial cells suggests that this recently identified lipase is intricately involved in modulating vessel wall lipid metabolism and may play a role in vascular diseases such as atherosclerosis.

    View details for Web of Science ID 000087378900015

    View details for PubMedID 10872808

  • Asymmetric dimethylarginine increases mononuclear cell adhesiveness in hypercholesterolemic humans ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Chan, J. R., Boger, R. H., Bode-Boger, S. M., Tangphao, O., Tsao, P. S., Blaschke, T. F., Cooke, J. P. 2000; 20 (4): 1040-1046

    Abstract

    Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, is elevated in hypercholesterolemia. This study was designed to determine the role of ADMA in the increased mononuclear cell adhesiveness observed in human hypercholesterolemia. In patient studies, plasma ADMA levels were determined by high-performance liquid chromatography. Functional mononuclear leukocyte adhesion assays were performed in parallel, and flow cytometry was used to characterize bound monocytes and T lymphocytes. Hypercholesterolemic patients were then placed on an oral L-arginine regimen of 14 or 21 g/d and studied over 12 weeks. In cell culture studies, bovine aortic endothelial cells were incubated with varied concentrations of ADMA. Monocytoid cells were cocultured with these bovine aortic endothelial cells, and their adhesiveness was assessed by use of a binding assay. Flow cytometry was used to quantify adhesion molecule expression. Plasma ADMA levels and adhesiveness of mononuclear cells (specifically, monocytes and T lymphocytes) were elevated in hypercholesterolemic patients. Adhesiveness was inversely correlated with the plasma L-arginine/ADMA ratio. Oral administration of L-arginine normalized plasma L-arginine/ADMA ratios and attenuated monocyte and T-lymphocyte adhesiveness. ADMA had no direct effect on the adhesiveness of mononuclear cells. However, monocytes became hyperadhesive when cocultured with ADMA-exposed endothelial cells. In human hypercholesterolemia, the plasma L-arginine/ADMA ratio is inversely correlated with mononuclear cell adhesiveness. Restoration of the L-arginine/ADMA ratio to control levels normalizes mononuclear cell adhesiveness. Our studies suggest that the elaboration of endothelium-derived nitric oxide affects the behavior of circulating T lymphocytes and monocytes.

    View details for Web of Science ID 000086468300020

    View details for PubMedID 10764670

  • Nicotine is an agent of angiogenesis: Role of nitric oxide and prostacyclin Heeschen, C., Ho, H. K., Jang, J., Kaji, S., Yang, P., Hu, B. S., Tsao, P., Cooke, J. P. ELSEVIER SCIENCE INC. 2000: 545A–546A
  • Flow-responsive remodeling after angioplasty is dependent on oxidant stress Ward, M. R., Tsao, P. S., Herity, N. A., Cooke, J. P., Yeung, A. C. LIPPINCOTT WILLIAMS & WILKINS. 1999: 699–99
  • Gene transfer of nitric oxide synthase - Effects on endothelial biology JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Niebauer, J., Dulak, J., Chan, J. R., Tsao, P. S., Cooke, J. P. 1999; 34 (4): 1201-1207

    Abstract

    The purpose of the study was to investigate the role of nitric oxide (NO) in monocyte-endothelial interaction by augmenting NO release via transfection of human endothelial cells (ECs) with EC NO synthase (eNOS) DNA.Enhancement of NO synthesis by L-arginine or shear stress reduces endothelial adhesiveness for monocytes and inhibits atherogenesis. To elucidate further the underlying mechanism, we augmented NO synthase expression by transfection of human EC.Liposome-mediated transfection of EC was performed with a plasmid construct containing the gene encoding eNOS. Expression of eNOS was confirmed by reverse transcription-polymerase chain reaction (RT-PCR). Endothelial cells were exposed to human monocytoid cells, and adherent cells were quantitated using a computer-assisted program. Nitric oxide was measured by chemiluminescence.The NO levels were not different in EC that were either not transfected, transfected with beta-gal or liposomes only. The nitric oxide synthase (NOS) transfection increased NO release by +60% (n = 6), which increased further when EC were stimulated by shear stress (24 h) by +137% (n = 5) as compared with untransfected, unstimulated EC (both p < 0.05). The RT-PCR revealed diminished monocyte chemotactic protein-1 (MCP-1) expression in eNOS transfected EC. There was an inverse relation between NO levels and monocyte binding (r = -0.5669, p < 0.002). Stimulation of EC with tumor necrosis factor-alpha (TNF-alpha; 250 U/ml) led to a decrease in NO synthesis, and an increase in monocyte binding. Cells transfected with NOS were resistant to both effects of TNF-alpha.Endothelial cells transfected with eNOS synthesize an increased amount of NO; this is associated with diminished MCP-1 expression and monocyte-endothelial binding. The reduction in monocyte-endothelial binding persists even after cytokine stimulation.

    View details for Web of Science ID 000082936900039

    View details for PubMedID 10520813

  • Enhanced monocyte adherence to thoracic aortae from rats with two forms of experimental hypertension AMERICAN JOURNAL OF HYPERTENSION Asagami, T., Reaven, G. M., Tsao, P. S. 1999; 12 (9): 890-893

    Abstract

    To extend our previous observation that thoracic aortae from rats with spontaneous hypertension (SHR) bind monocytoid cells with enhanced avidity, we isolated thoracic aortae from two different forms of rodent hypertension: Dahl salt-sensitive (Dahl-S) rats fed a high salt diet and Sprague-Dawley (S-D) rats fed a fructose-enriched diet. Blood pressure was determined 14 days after feeding normal chow or chow containing 8% NaCl to Dahl-S and Dahl salt-resistant (Dahl-R) rats, and either chow or a fructose-enriched diet to S-D and Fischer 344 (F-344) rats. Blood pressure was similar in Dahl-S and Dahl-R rats on the chow diet, but higher in Dahl-S rats in response to the 8% NaCl diet (188 +/- 7 v 137 +/- 3 mm Hg, P < .001). Blood pressure also increased when S-D rats consumed fructose as compared with chow (149 +/- 4 v 128 +/-2, P < .05), whereas blood pressure did not change with diet in F-344. Thoracic aortae were removed from rats in each experimental group, and their ability to bind murine monocytoid cells quantified. Measurements of monocyte binding were performed on one experimental and one control rat simultaneously, and results presented as the ratio of cells bound by thoracic aortae from the experimental compared with the control rat. With this approach, the ratio of monocyte binding (8% NaCl/chow) was increased in Dahl-S versus Dahl-R rats (1.7 +/- 0.1 v 1.3 +/- 0.1, P < .05), as well as in S-D as compared with F-344 rats (1.7 +/- 0.2 v 1.1 +/-0.1, P < .05). These results provide evidence that hypertension in Dahl-S and fructose-fed S-D rats was associated with changes in the endothelium that favor atherogenesis.

    View details for Web of Science ID 000082738300006

    View details for PubMedID 10509546

  • Mononuclear cell adherence to cultured endothelium is enhanced by hypertension and insulin resistance in healthy nondiabetic volunteers CIRCULATION Chen, N. G., Abbasi, F., Lamendola, C., McLaughlin, T., Cooke, J. P., Tsao, P. S., Reaven, G. M. 1999; 100 (9): 940-943

    Abstract

    This study was initiated to compare the adherence to cultured endothelial cells of mononuclear cells isolated from normotensive and hypertensive individuals.Mononuclear cell binding to endothelium was greater in patients with hypertension (32+/-1 versus 25+/-2; P<0.001) than in normal volunteers. There was a significant relationship (r=0.42, P<0. 01) between mononuclear cell binding and mean arterial pressure, independent of differences in age, sex, and body mass index. A significant relationship also existed between insulin resistance (estimated by the steady-state plasma glucose concentration during the insulin suppression test) and mononuclear cell binding in both the normotensive (r=0.86, P<0.001) and hypertensive (r=0.74, P<0. 001) groups. Furthermore, multiple regression analysis demonstrated an independent relationship (P<0.001) between mononuclear cell binding and both steady-state plasma glucose and hypertensive status.These results indicate that both hypertension and insulin resistance lead to changes in mononuclear cells that increase their adherence to cultured endothelial cells.

    View details for Web of Science ID 000082353000009

    View details for PubMedID 10468524

  • Novel mechanism for endothelial dysfunction - Dysregulation of dimethylarginine dimethylaminohydrolase CIRCULATION Ito, A., Tsao, P. S., Adimoolam, S., Kimoto, M., Ogawa, T., Cooke, J. P. 1999; 99 (24): 3092-3095

    Abstract

    Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase (NOS). Plasma levels of ADMA are elevated in individuals with hypercholesterolemia or atherosclerosis. We postulated that reduced degradation of ADMA may play a role in the accumulation of ADMA in these individuals. Accordingly, we studied the effects of oxidized LDL (oxLDL) or tumor necrosis factor-alpha (TNF-alpha) on the accumulation of ADMA by transformed human umbilical vein endothelial cells (ECV304) and on the enzyme dimethylarginine dimethylaminohydrolase (DDAH), which degrades ADMA.ECV304 were incubated with or without native LDL (100 micrograms/mL), oxLDL (100 micrograms/mL), or TNF-alpha (250 U/mL) for 48 hours. The concentration of ADMA in the conditioned medium was determined by high-performance liquid chromatography. Western blotting was performed to evaluate DDAH expression. We assayed DDAH activity by determining L-citrulline formation from ADMA. The addition of oxLDL or TNF-alpha to ECV304 significantly increased the level of ADMA in the conditioned medium. The effect of oxLDL or TNF-alpha was not due to a change in DDAH expression but rather to the reduction of DDAH activity. To determine whether dysregulation of DDAH also occurred in vivo, New Zealand White rabbits were fed normal chow or a high-cholesterol diet. Hypercholesterolemia significantly reduced aortic, renal, and hepatic DDAH activity.These results suggest that the endothelial vasodilator dysfunction observed in hypercholesterolemia may be due to reduced degradation of ADMA, the endogenous inhibitor of NOS.

    View details for Web of Science ID 000080943900003

    View details for PubMedID 10377069

  • Impaired aerobic capacity in hypercholesterolemic mice: partial reversal by exercise training AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY Niebauer, J., Maxwell, A. J., Lin, P. S., Tsao, P. S., Kosek, J., Bernstein, D., Cooke, J. P. 1999; 276 (4): H1346-H1354

    Abstract

    The present study assessed whether impaired aerobic capacity previously observed in hypercholesterolemic mice is reversible by exercise training. Seventy-two 8-wk-old female C57BL/6J wild-type (+, n = 42) and apolipoprotein E-deficient (-, n = 30) mice were assigned to the following eight interventions: normal chow, sedentary (E+, n = 17; E-, n = 8) or exercised (E+ex, n = 13; E-ex, n = 7) and high-fat chow, sedentary (E+chol, n = 6; E-chol, n = 8) or exercised (E+chol-ex, n = 6; E-chol-ex, n = 7). Mice were trained on a treadmill 2 x 1 h/day, 6 days/wk, for 4 wk. Cholesterol levels correlated inversely with maximum oxygen uptake (r = -0.35; P < 0. 02), which was blunted in all hypercholesterolemic sedentary groups (all P < 0.05). Maximum oxygen uptake improved in all training groups but failed to match E+ex (all P < 0.05). Vascular reactivity and nitric oxide (NO) synthesis correlated with anaerobic threshold (r = 0.36; P < 0.025) and maximal distance run (r = 0.59; P < 0.007). We conclude that genetically induced hypercholesterolemia impairs aerobic capacity. This adverse impact of hypercholesterolemia on aerobic capacity may be related to its impairment of vascular NO synthesis and/or vascular smooth muscle sensitivity to nitrovasodilators. Aerobic capacity is improved to the same degree by exercise training in normal and genetically hypercholesterolemic mice, although there remains a persistent difference between these groups after training.

    View details for Web of Science ID 000079554200030

    View details for PubMedID 10199861

  • Impaired aerobic capacity in hypercholesterolemic mice: partial reversal by exercise training. American journal of physiology. Heart and circulatory physiology Niebauer, J., Maxwell, A. J., Lin, P. S., Tsao, P. S., Kosek, J., Bernstein, D., Cooke, J. P. 1999; 276 (4): H1346–H1354

    Abstract

    The present study assessed whether impaired aerobic capacity previously observed in hypercholesterolemic mice is reversible by exercise training. Seventy-two 8-wk-old female C57BL/6J wild-type (+, n = 42) and apolipoprotein E-deficient (-, n = 30) mice were assigned to the following eight interventions: normal chow, sedentary (E+, n = 17; E-, n = 8) or exercised ([Formula: see text], n= 13; [Formula: see text], n = 7) and high-fat chow, sedentary ([Formula: see text], n = 6;[Formula: see text], n = 8) or exercised ([Formula: see text], n = 6;[Formula: see text], n = 7). Mice were trained on a treadmill 2 * 1 h/day, 6 days/wk, for 4 wk. Cholesterol levels correlated inversely with maximum oxygen uptake ( r = -0.35; P < 0.02), which was blunted in all hypercholesterolemic sedentary groups (all P < 0.05). Maximum oxygen uptake improved in all training groups but failed to match[Formula: see text] (all P< 0.05). Vascular reactivity and nitric oxide (NO) synthesis correlated with anaerobic threshold ( r = 0.36; P < 0.025) and maximal distance run ( r = 0.59; P < 0.007). We conclude that genetically induced hypercholesterolemia impairs aerobic capacity. This adverse impact of hypercholesterolemia on aerobic capacity may be related to its impairment of vascular NO synthesis and/or vascular smooth muscle sensitivity to nitrovasodilators. Aerobic capacity is improved to the same degree by exercise training in normal and genetically hypercholesterolemic mice, although there remains a persistent difference between these groups after training.

    View details for DOI 10.1152/ajpheart.1999.276.4.H1346

    View details for PubMedID 29598201

  • Regression of atherosclerosis - Role of nitric oxide and apoptosis CIRCULATION Wang, B. Y., Ho, H. K., Lin, P. S., Schwarzacher, S. P., Pollman, M. J., Gibbons, G. H., Tsao, P. S., Cooke, J. P. 1999; 99 (9): 1236-1241

    Abstract

    We have recently found that administration of L-arginine to hypercholesterolemic rabbits induces regression of preexisting lesions. Others have previously shown that activation of the L-arginine/nitric oxide (NO) synthase pathway can induce apoptosis of vascular cells in vitro. Accordingly, the current study was designed to determine if dietary supplementation of L-arginine induces apoptosis of intimal lesions and if this effect is mediated through the NO synthase pathway.Male New Zealand White rabbits were fed a 0.5% cholesterol diet for 10 weeks and subsequently placed on 2.5% L-arginine HCl in the drinking water, and the cholesterol diet was continued for 2 weeks, at which time the aortas were harvested for histological studies. L-Arginine treatment increased the number of apoptotic cells (largely macrophages) in the intimal lesions by 3-fold (11.9+/-3.9 vs 3.9+/-1. 4 apoptotic cells/mm2, P<0.01). In subsequent studies, aortas were harvested for ex vivo studies. Aortic segments were incubated in cell culture medium for 4 to 24 hours with modulators of the NO synthase pathway. The tissues were then collected for histological studies and the conditioned medium collected for measurement of nitrogen oxides by chemiluminescence. Addition of sodium nitroprusside (10(-5) mol/L) to the medium caused a time-dependent increase in apoptosis of vascular cells (largely macrophages) in the intimal lesion. L-Arginine (10(-3) mol/L) had an identical effect on apoptosis, which was associated with an increase in nitrogen oxides released into the medium. These effects were not mimicked by D-arginine, and they were antagonized by the NO synthase inhibitor L-nitro-arginine (10(-4) mol/L). The effect of L-arginine was not influenced by an antagonist of cGMP-dependent protein kinase, nor was the effect mimicked by the agonist of protein kinase G or 8-BR cGMP.These results indicate that supplemental L-arginine induces apoptosis of macrophages in intimal lesions by its metabolism to NO, which acts through a cGMP-independent pathway. These studies are consistent with our previous observation that supplementation of dietary arginine induces regression of atheroma in this animal model. These studies provide a rationale for further investigation of the therapeutic potential of manipulating the NO synthase pathway in atherosclerosis.

    View details for Web of Science ID 000078978500016

    View details for PubMedID 10069793

  • Asymmetric dimethylarginine (ADMA): A novel risk factor for endothelial dysfunction - Its role in hypercholesterolemia CIRCULATION Boger, R. H., Bode-Boger, S. M., Szuba, A., Tsao, P. S., Chan, J. R., Tangphao, O., Blaschke, T. F., Cooke, J. P. 1998; 98 (18): 1842-1847

    Abstract

    Asymmetric dimethylarginine (ADMA) is an endogenous competitive inhibitor of nitric oxide (NO) synthase. Because endothelial NO elaboration is impaired in hypercholesterolemia, we investigated whether plasma concentrations of ADMA are elevated in young, clinically asymptomatic hypercholesterolemic adults. We further studied whether such elevation of ADMA levels was correlated with impaired endothelium-dependent, NO-mediated vasodilation and urinary nitrate excretion. In a randomized, double-blind, placebo-controlled study, we investigated whether these changes could be reversed with exogenous L-arginine.We measured plasma levels of L-arginine, ADMA, and symmetrical dimethylarginine (SDMA) by high-performance liquid chromatography in 49 hypercholesterolemic (HC) and 31 normocholesterolemic (NC) humans. In 8 HC subjects, endothelium-dependent forearm vasodilation was assessed before and after an intravenous infusion of L-arginine or placebo and compared with 8 NC control subjects. ADMA levels were significantly elevated by >100% (2.17+/-0.15 versus 1.03+/-0.09 micromol/L; P<0.05) in HC subjects compared with NC adults. L-Arginine levels were similar, resulting in a significantly decreased L-arginine/ADMA ratio in HC subjects (27.7+/-2.4 versus 55. 7+/-5.4; P<0.05). In 8 HC subjects, intravenous infusion of L-arginine significantly increased the L-arginine/ADMA ratio and normalized endothelium-dependent vasodilation and urinary nitrate excretion. ADMA levels were inversely correlated with endothelium-mediated vasodilation (R=0.762, P<0.01) and urinary nitrate excretion rates (R=0.534, P<0.01).We find that ADMA is elevated in young HC individuals. Elevation of ADMA is associated with impaired endothelium-dependent vasodilation and reduced urinary nitrate excretion. This abnormality is reversed by administration of L-arginine. ADMA may be a novel risk factor for endothelial dysfunction in humans.

    View details for Web of Science ID 000076718900005

    View details for PubMedID 9799202

  • Adherence of mononuclear cells to endothelium is increased in patients with hypertension Chen, N. G., Abbasi, F. A., CHEN, Y. D., Cooke, J. P., Tsao, P. S., Reaven, G. M. LIPPINCOTT WILLIAMS & WILKINS. 1998: 376–76
  • Modulation of the nitric oxide synthase pathway in atherosclerosis EXPERIMENTAL PHYSIOLOGY Maxwell, A. J., Tsao, P. S., Cooke, J. P. 1998; 83 (5): 573-584

    View details for Web of Science ID 000076498500001

    View details for PubMedID 9793778

  • Interaction of diabetes and hypertension on determinants of endothelial adhesiveness ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Tsao, P. S., Niebauer, J., Buitrago, R., Lin, P. S., Wang, B. Y., Cooke, J. P., CHEN, Y. D., Reaven, G. M. 1998; 18 (6): 947-953

    Abstract

    Epidemiological studies have established that diabetes mellitus and hypertension are independent risk factors for atherosclerosis. One of the earliest abnormalities seen in atherogenesis is enhanced monocyte adherence to the endothelium. The mechanisms by which diabetes mellitus or hypertension enhances monocyte-endothelial cell interactions are incompletely characterized. It is not known whether there are additive interactions between these risk factors on endothelial adhesiveness for monocytes. Male Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats were fed a normal or fructose-enriched diet. In some cases, animals were injected with streptozotocin (35 mg/kg body weight) to induce diabetes. After 2 weeks, plasma was drawn for biochemical measurements, and thoracic aortas were harvested, opened longitudinally, and exposed to fluorescently labeled mouse monocytoid cells (WEHI 78/24, 2 x 10(6)/mL) for 30 minutes on a rocking platform. Adherent cells were counted by epifluorescence microscopy. WEHI 78/24 binding to aortic segments from SHR animals was elevated compared with segments from WKYs. Fructose feeding alone had no effect on endothelial adhesiveness. When WKYs were made hyperglycemic by STZ injection, monocyte binding was 160% of the control value. Elevated monocyte binding was also observed in aortas derived from SHR animals injected with STZ, indicating an additive effect of hypertension and hyperglycemia. To determine whether alterations in oxidative state played a role in the endothelial adhesiveness, aortic segments were exposed to lucigenin (250 micromol/L) for measurement of superoxide anion. Aortic segments from SHR elaborated 120% more superoxide anion than did controls. Elevated free-radical production was also observed in aortas from diabetic WKYs. Furthermore, thoracic aortas derived from diabetic SHR animals elaborated more superoxide anion than did any of the other groups (374%, P<0.05). Immunohistochemical staining for monocyte chemotactic protein-1 demonstrated increased expression in aortas isolated from diabetic WKY and SHR compared with control vessels. These studies demonstrate that both diabetes and hypertension lead to increased monocyte adherence to the endothelium. This abnormality is associated with increased vascular superoxide production and monocyte chemotactic protein-1 expression. Furthermore, there appears to be an additive interaction between hyperglycemia and hypertension in their effects on endothelial adhesiveness and its determinants.

    View details for Web of Science ID 000074175500014

    View details for PubMedID 9633936

  • Effect of cyclosporine on chronic graft vascular disease in a rat cardiac isograft model International Congress on Immunosuppression Teranishi, K., Poston, R. S., Tsao, P. S., Asagami, T., Cooke, J. P., Reitz, B. A., Robbins, R. C. ELSEVIER SCIENCE INC. 1998: 1012–13

    View details for Web of Science ID 000074150800034

    View details for PubMedID 9636409

  • Protein kinase C-epsilon mediates glucose-induced superoxide production and MCP-1 expression in endothelial cells Tsao, P. S., Heidary, S., Wang, A., Chan, J. R., Reaven, G. M., Cooke, J. P. FEDERATION AMER SOC EXP BIOL. 1998: A88–A88
  • Endothelial alterations in hypercholesterolemia: More than simply vasodilator dysfunction 1st Meeting of the International Scientific Faculty on Endothelial Function Tsao, P. S., Cooke, J. P. LIPPINCOTT WILLIAMS & WILKINS. 1998: S48–S53

    Abstract

    Occlusive vascular disease begins with an alteration of the endothelium, which is characterized by a decrease in nitric oxide (NO) activity. Endogenous NO inhibits many key processes in atherogenesis, including monocyte adherence, platelet activation, and smooth muscle proliferation. The mechanism by which NO activity is reduced in hypercholesterolemia and in other metabolic disorders associated with atherogenesis appears to be multifactorial. It includes increased production of oxygen-derived free radicals, alterations in NO synthase, and the accumulation of endogenous inhibitors (ADMA) of NO synthase. Plasma concentrations of ADMA are elevated in hypercholesterolemic humans. Elevated ADMA concentrations are associated with impaired endothelium-dependent, NO-mediated vasodilatation and reduced urinary nitrate exertion. These effects of ADMA are counteracted by administration of the NO precursor L-arginine. It is likely that basic insights regarding the mechanisms of endothelial dysfunction will lead to new therapeutic strategies for atherosclerosis.

    View details for Web of Science ID 000077892100009

    View details for PubMedID 9883748

  • Adhesiveness of mononuclear cells in hypercholesterolemic humans is normalized by dietary L-arginine ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Theilmeier, G., Chan, J. R., Zalpour, C., Anderson, B., Wang, B. Y., Wolf, A., Tsao, P. S., Cooke, J. P. 1997; 17 (12): 3557-3564

    Abstract

    Hypercholesterolemia reduces vascular nitric oxide (NO) activity. This dysfunction may promote endothelial monocyte interaction, as NO is a potent inhibitor of cell adhesion. We have previously shown that in hypercholesterolemic (HC) rabbits, chronic oral supplementation of L-arginine (Arg) restores NO activity and inhibits monocyte-endothelial cell interaction, in association with a reduction in atherogenesis. We hypothesized that enhancement of endothelial NO activity in HC humans would reduce monocyte adhesiveness. We used a functional binding assay to assess the adhesiveness of human mononuclear cells (MNCs) ex vivo to determine the effects of hypercholesterolemia and L-arginine administration. MNCs from HC subjects adhered in greater numbers (50% more cells per high-power field; P < .0001) than cells derived from normocholesterolemic (NC) subjects. To determine whether enhancement of endogenous NO activity could inhibit mononuclear cell adhesiveness, in a double-blinded placebo-controlled study, oral arginine HCl (8.4 g/d) was administered to HC subjects. Over a course of 2 weeks, this treatment abolished the increased adhesiveness of HC MNCs (160 +/- 11% versus 104 +/- 5%; before and after 2 weeks of Arg treatment; results expressed as a percentage of the binding values obtained using cells derived from paired NC individuals). By contrast, MNC adhesion remained significantly elevated in placebo-treated HC subjects. To examine whether endothelium-derived NO could act as a paracrine modulator of monocyte behavior, monocytes were exposed to NO donors or cocultered in the presence of endothelial cells exposed to antagonists of NO synthase in the presence or absence of L-arginine. NO donors inhibited monocyte adhesiveness. Furthermore, the adhesiveness of monocytes cocultured with endothelial cells was increased by antagonists of NO synthase; this effect was reversed by L-arginine. This study shows that the adhesiveness of human MNCs is increased by hypercholesterolemia. The increase in adhesiveness was reversed in vivo by administration of the NO precursor L-arginine. NO donors or endothelium-derived NO inhibits the adhesiveness of monocytes in vitro, supporting the hypothesis that the effects of L-arginine are mediated by NO.

    View details for Web of Science ID 000072212600025

    View details for PubMedID 9437205

  • Anti-CD43 inhibits monocyte-endothelial adhesion in inflammation and atherogenesis BLOOD McEvoy, L. M., JUTILA, M. A., Tsao, P. S., Cooke, J. P., BUTCHER, E. C. 1997; 90 (9): 3587-3594

    Abstract

    Recruitment of blood monocytes into tissues is a central event in the inflammatory response and in atherogenesis. The mechanisms leading to monocyte adhesion and migration through endothelium are not completely defined. We recently reported that MAb L11, against the leukocyte sialomucin CD43, blocks T-lymphocyte binding to lymph node and Peyer's patch high endothelial venules (HEV) and inhibits T-cell extravasation from the blood into organized secondary lymphoid tissues. We have now assessed the ability of L11 to inhibit monocyte-endothelial (EC) interactions and trafficking. L11 blocks binding of WEHI78/24 cells, a murine monocytoid cell line, to inflamed lymph node HEV and inhibits recruitment of monocytes and neutrophils to thioglycollate-inflamed peritoneum. Because monocyte adhesion to the endothelium and diapedesis in lesion-prone regions of the vasculature is among the earliest events in atherogenesis, leading to formation of lipid-laden foam cells, the ability of L11 to block monocyte recognition of aortic endothelial cells was assessed in a novel ex vivo assay of monocyte binding to intact rabbit aortic endothelium. Cholesterol feeding of rabbits induces enhanced aortic adhesiveness for monocytes and WEHI78/24 monocytoid cells, and this adhesion is inhibited by L11. The inhibitory effect of L11 is additive with that of a cocktail of anti-L-selectin and anti-alpha4 and beta2 integrin monoclonal antibodies. Thus, CD43 represents a novel target for manipulation of monocyte recruitment in inflammation and atherogenesis.

    View details for Web of Science ID A1997YD10800034

    View details for PubMedID 9345042

  • Adherence of mononuclear cells to endothelium in vitro is increased in patients with NIDDM DIABETES CARE Carantoni, M., Abbasi, F., Chu, L., CHEN, Y. D., Reaven, G. M., Tsao, P. S., Varasteh, B., Cooke, J. P. 1997; 20 (9): 1462-1465

    Abstract

    To compare the binding to cultured endothelial cells of mononuclear cells isolated from healthy volunteers and patients with NIDDM.Mononuclear cells were isolated from healthy volunteers (n = 11) and patients with NIDDM (n = 14) and incubated with ECV 304 cells, a human umbilical endothelial cell-derived transformed cell line. Following a period of incubation, the adherence of mononuclear cells to endothelial cells was determined.Adherence of mononuclear cells from patients with NIDDM was significantly greater (P < 0.05) than that of cells isolated from the healthy volunteers, and this difference persisted when adjusted for age, sex, and degree of obesity. Mononuclear cell binding to ECV 304 cells correlated significantly with fasting plasma glucose (r = 0.52, P < 0.01), insulin (r = 0.51, P < 0.01), triglyceride (r = 0.54, P < 0.01), and VLDL (r = 0.54, P < 0.01) and HDL cholesterol (r = -0.45, P < 0.05) levels, but not with either total or LDL cholesterol levels or blood pressure.Since the adherence of mononuclear cells to the endothelium represents the earliest step in atherogenesis, the observation that mononuclear cells from patients with NIDDM bind more avidly to cultured endothelial cells may help explain why accelerated atherosclerosis occurs in patients with NIDDM. The metabolic abnormality, or abnormalities, present in patients with NIDDM that is responsible for the enhanced adhesiveness of mononuclear cells requires further examination.

    View details for PubMedID 9283798

  • Nitric oxide regulates monocyte chemotactic protein-1 CIRCULATION Tsao, P. S., Wang, B. Y., Buitrago, R., Shyy, J. Y., Cooke, J. P. 1997; 96 (3): 934-940

    Abstract

    Monocyte chemotactic protein-1 (MCP-1) is a 76-amino-acid chemokine thought to be the major chemotactic factor for monocytes. We and others have demonstrated that NO inhibits monocyte-endothelial cell interactions and atherogenesis. We hypothesize that the antiatherogenic effect of NO may be due in part to its inhibition of MCP-1 expression.Smooth muscle cells (SMCs) were isolated from normal rabbit aortas by the explant method. Cells were then exposed to LPS (10 microg/mL), native LDL, or oxidized LDL (30 microg/mL) for 6 hours. The expression of MCP-1 in SMCs and chemotactic activity in the conditioned medium were induced by lipopolysaccharide (LPS) or by oxidized LDL but not native LDL. The induction of MCP-1 by cytokines or oxidized lipoproteins was associated with an increased generation of superoxide anion by the SMCs and increased activity of the transcriptional protein nuclear factor-kappaB (NFkappaB). The induced expression of MCP-1 and activation of NFkappaB were reduced by previous exposure of the SMCs to the NO donor DETA-NONOate (100 micromol/L) (P<.05). To determine whether NO exerted its effect at a transcriptional level, SMCs and COS cells were transfected with a 400-bp fragment of the MCP-1 promoter. Promoter activity was enhanced by oxidized LDL, and LPS was inhibited by DETA-NO. Nuclear run-on assays confirmed that the effect of NO occurred at a transcriptional level. To investigate the role of endogenous NO in the regulation of MCP-1 in vivo, New Zealand White rabbits were fed normal chow, normal chow plus nitro-L-arginine (LNA), high-cholesterol diet (Chol), or high-cholesterol diet supplemented with L-arginine (Arg). After 2 weeks, thoracic aortas were harvested and total RNA was isolated. Northern analysis using full-length MCP-1 cDNA demonstrated increased expression in Chol and LNA aortas; this expression was decreased in aortas from Arg animals.These studies indicate that the antiatherogenic effect of NO may be mediated in part by its inhibition of MCP-1 expression.

    View details for Web of Science ID A1997XP13000035

    View details for PubMedID 9264504

  • Novel vascular molecule involved in monocyte adhesion to aortic endothelium in models of atherogenesis JOURNAL OF EXPERIMENTAL MEDICINE McEvoy, L. M., Sun, H. L., Tsao, P. S., Cooke, J. P., Berliner, J. A., BUTCHER, E. C. 1997; 185 (12): 2069-2077

    Abstract

    Adhesion of monocytes to the endothelium in lesion-prone areas is one of the earliest events in fatty streak formation leading to atherogenesis. The molecular basis of increased monocyte adhesion is not fully characterized. We have identified a novel vascular monocyte adhesion-associated protein, VMAP-1, that plays a role in adhesion of monocytes to activated endothelium. Originally selected for its ability to block binding of a mouse monocyte-like cell line (WEHI78/24) to cytokine- or LPS-stimulated cultured mouse endothelial cells in vitro, antiVMAP-1 mAb LM151 cross-reacts with rabbit endothelium and blocks binding of human monocytes to cultured rabbit aortic endothelial cells stimulated with minimally modified low density lipoprotein, thought to be a physiologically relevant atherogenic stimulus. Most importantly, LM151 prevents adhesion of normal monocytes and monocytoid cells to intact aortic endothelium from cholesterol-fed rabbits in an ex vivo assay. VMAP-1 is a 50-kD protein. Immunohistology of vessels reveals focal constitutive expression in aorta and other large vessels. VMAP-1 is thus a novel vascular adhesion-associated protein that appears to play a critical role in monocyte adhesion to aortic endothelial cells in atherogenesis in vivo.

    View details for Web of Science ID A1997XF79100005

    View details for PubMedID 9182678

  • Cell cycle inhibition preserves endothelial function in genetically engineered rabbit vein grafts JOURNAL OF CLINICAL INVESTIGATION Mann, M. J., Gibbons, G. H., Tsao, P. S., VONDERLEYEN, H. E., Cooke, J. P., Buitrago, R., Kernoff, R., Dzau, V. J. 1997; 99 (6): 1295-1301

    Abstract

    We have recently shown that ex vivo gene therapy of rabbit autologous vein grafts with antisense oligodeoxynucleotides (AS ODN) blocking cell cycle regulatory gene expression inhibits not only neointimal hyperplasia, but also diet-induced, accelerated graft atherosclerosis. We observed that these grafts remained free of macrophage invasion and foam cell deposition. Since endothelial dysfunction plays an important role in vascular disease, the current study examined the effect of this genetic engineering strategy on graft endothelial function and its potential relationship to the engineered vessels' resistance to atherosclerosis. Rabbit vein grafts transfected with AS ODN against proliferating cell nuclear antigen (PCNA) and cell division cycle 2 (cdc2) kinase elaborated significantly more nitric oxide and exhibited greater vasorelaxation to both calcium ionophore and acetylcholine than did untreated or control ODN-treated grafts. This preservation of endothelial function was associated with a reduction in superoxide radical generation, vascular cell adhesion molecule-1 (VCAM-1) expression, and monocyte binding activity in grafts in both normal and hypercholesterolemic rabbits. Our data demonstrate that AS ODN arrest of vascular cell cycle progression results in the preservation of normal endothelial phenotype and function, thereby influencing the biology of the vessel wall towards a reduction of its susceptibility to occlusive disease.

    View details for Web of Science ID A1997WQ61300023

    View details for PubMedID 9077539

    View details for PubMedCentralID PMC507945

  • Dietary L-arginine supplementation normalizes platelet aggregation in hypercholesterolemic humans JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Wolf, A., Zalpour, C., Theilmeier, G., Wang, B. Y., Ma, A., Anderson, B., Tsao, P. S., Cooke, J. P. 1997; 29 (3): 479-485

    Abstract

    The present study was designed to test the hypothesis that long-term dietary supplementation with the nitric oxide precursor L-arginine would enhance vascular or platelet-derived nitric oxide activity, or both, and thereby inhibit platelet reactivity in hypercholesterolemic humans.We have shown that reduced vascular activity of nitric oxide in hypercholesterolemic rabbits can be restored by L-arginine supplementation. The improvement in nitric oxide activity is associated with an inhibition of platelet aggregation ex vivo. This effect is most likely due to increased elaboration of endothelium- or platelet-derived nitric oxide, or both, because the inhibition of platelet reactivity was associated with elevation of intraplatelet cyclic guanosine monophosphate and was reversed by the nitric oxide synthase antagonist N-methyl-arginine.In a double-blinded, randomized, placebo-controlled trial, hypercholesterolemic patients were assigned to L-arginine hydrochloride, 8.4 g/day orally, or placebo for 2 weeks. Platelet-rich plasma was obtained for aggregometry induced by collagen (1 to 10 micrograms/ml) at four points: baseline, after 2 weeks of treatment, after a 2-week washout and after a long-term washout of 16 weeks on average. Aggregation was quantified by light transmittance and expressed as a percent transmittance observed with platelet-poor plasma.Compared with normocholesterolemic control subjects, platelets from hypercholesterolemic subjects stimulated with 5 micrograms/ml of collagen showed increased aggregability (68.6% in hypercholesterolemic patients vs. 54.5% in normocholesterolemic control subjects, p < or = 0.02). After 2 weeks of treatment with L-arginine (but not placebo), platelet reactivity was modestly reduced; this effect persisted for 2 weeks after discontinuation of arginine (52.6% in arginine-treated patients vs. 65.1% in normocholesterolemic control subjects, p = 0.07). After 18 weeks (i.e., 16 weeks after discontinuing arginine treatment), the platelets of hypercholesterolemic patients once again became hyperaggregable, and the extent of platelet aggregation was significantly increased compared with the 4-week point (73.6% after vs. 52.6% during arginine treatment, p < 0.01). No significant change in platelet reactivity was seen in placebo-treated hypercholesterolemic patients throughout the study. L-Arginine treatment was well tolerated without side effects.This double-blinded, placebo-controlled study demonstrates that dietary supplementation with L-arginine can modestly attenuate the increased platelet reactivity seen in hypercholesterolemic patients. The data are consistent with our previous studies in hypercholesterolemic animals, demonstrating that L-arginine restores endogenous nitric oxide activity and inhibits platelet aggregation. Enhancement of endogenous nitric oxide activity is a potential novel therapeutic strategy worthy of further study.

    View details for Web of Science ID A1997WL49000002

    View details for PubMedID 9060881

  • The role of endothelium-derived nitric oxide in atherosclerosis European Congress of Angiology, 11th Meeting of the European Chapter (EUROCHAP 97) Cooke, J. P., Tsao, P. S. ELSEVIER SCIENCE BV. 1997: 3–14
  • Arginine restores nitric oxide activity and inhibits monocyte accumulation after vascular injury in hypercholesterolemic rabbits JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Wang, B. Y., Candipan, R. C., Arjomandi, M., HSIUN, P. T., Tsao, P. S., Cooke, J. P. 1996; 28 (6): 1573-1579

    Abstract

    This study sought to determine whether the alterations in vascular function and structure after balloon injury in hypercholesterolemic rabbits could be inhibited by dietary arginine.Administration of arginine (the nitric oxide [NO] precursor) restores vascular NO activity in hypercholesterolemic animals. We and other investigators have shown that enhancement of vascular NO activity can inhibit myointimal hyperplasia after vascular injury in normocholesterolemic animals.Twenty-eight New Zealand White rabbits received either normal rabbit chow, 0.5% cholesterol diet or 0.5% cholesterol diet plus L-arginine hydrochloride (2.25% wt/vol) in the drinking water. After 6 weeks of dietary intervention, the left iliac artery of each animal was subjected to a balloon injury. Four weeks later, the iliac arteries were harvested for vascular reactivity studies and immunohistochemical analysis.Vascular injury induced intimal thickening that was largely composed of vascular smooth muscle cells and extracellular matrix. In the setting of hypercholesterolemia, vascular injury induced an exuberant myointimal lesion that was augmented by the accumulation of lipid-laden macrophages. Dietary arginine reduced intimal thickening in the injured vessels of hypercholes-terolemic animals and substantially inhibited the accumulation of macrophages in the lesion (from 28% to 5% of the lesion area, p < 0.001).We report that lesions induced by vascular injury in hypercholesterolemic animals are markedly reduced by oral administration of arginine. Moreover, we find that the nature of the lesion is altered, with a striking reduction in the percentage of macrophages comprising the lesion.

    View details for Web of Science ID A1996VT31000020

    View details for PubMedID 8917274

  • Intravascular stenting changes vascular distensibility and upregulates nitric oxide activity Schwarzacher, S. P., Niebauer, J., Hayase, M., Uren, N. G., Tsao, P., Yock, P. G., Yeung, A. C. LIPPINCOTT WILLIAMS & WILKINS. 1996: 1526–26
  • Nitric oxide induces regression: Role of apoptosis Wang, B. Y., Lin, P. S., Tsao, P. S., Cooke, J. P. LIPPINCOTT WILLIAMS & WILKINS. 1996: 900–900
  • Fluid flow inhibits endothelial adhesiveness - Nitric oxide and transcriptional regulation of VCAM-1 CIRCULATION Tsao, P. S., Buitrago, R., Chan, J. R., Cooke, J. P. 1996; 94 (7): 1682-1689

    Abstract

    In the arterial tree, regions exposed to reduced shear stress (low and/or disturbed flow) are predisposed to atherogenesis. Fluid flow is a potent stimulus for the release of endothelium-derived nitric oxide (NO). Because NO inhibits monocyte-endothelial cell interaction, we speculated that the effects of flow in inhibiting atherogenesis might be mediated in part by NO.Confluent monolayers of human aortic endothelial cells were exposed to static or fluid flow conditions for 4 hours. The medium was replaced, and cells were then incubated with native LDL (50 micrograms/mL), oxidized LDL (30 micrograms/mL), or lipopolysaccharide (LPS) (10 ng/mL)+tumor necrosis factor-alpha (TNF-alpha) (10 U/mL) for an additional 4 hours. Functional binding assays using THP-1 monocytes were then performed. Superoxide production by human aortic endothelial cells was monitored by lucigenin chemiluminescence, and expression of the adhesion molecules vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 were quantified by flow cytometry. Whereas native LDL had little effect, incubation with either oxidized LDL or LPS/TNF-alpha significantly increased superoxide production, nuclear factor-kappa B activity, VCAM-1 expression, and endothelial adhesiveness for monocytes. Previous exposure to fluid flow inhibited these sequelae of exposure to cytokines or oxidized lipoprotein. The effect of fluid flow appears to be due in part to shear-induced release of NO, because coincubation with nitro-L-arginine completely abolished these effects of flow. Furthermore, the NO donor PAPA-NONO-ate and 8-Br-cGMP (but not 8-Br-cAMP) mimicked the effects of flow.Previous exposure to fluid flow decreased cytokine- or lipoprotein-stimulated endothelial cell superoxide production, VCAM-1 expression, and monocyte binding; the effects of flow appear to be due to NO. Flow-mediated NO-dependent regulation of oxidant-responsive transcription may influence the site of a lesion.

    View details for Web of Science ID A1996VJ97900030

    View details for PubMedID 8840861

  • Hypertension-enhanced monocyte adhesion in experimental atherosclerosis JOURNAL OF VASCULAR SURGERY Tropea, B. I., Huie, P., Cooke, J. P., Tsao, P. S., Sibley, R. K., Zarins, C. K. 1996; 23 (4): 596-605

    Abstract

    Hypertension is a known clinical risk factor for atherosclerosis. In experimental atherosclerosis, monocyte adhesion to the endothelial surface is enhanced and is considered to be an important early stage in plaque formation. We tested the hypothesis that hypertension enhances monocyte adhesion in experimental atherosclerosis.Twenty-two New Zealand White rabbits were fed an atherogenic diet for 3 weeks to induce plaque formation. Aortic coarctation was created in eight rabbits by wrapping a Dacron band around the midportion of the descending thoracic aorta (stenosis group), whereas six rabbits underwent banding without aortic constriction (no stenosis group). Eight rabbits served as nonoperated controls. Monocyte binding to the aortic endothelial surface was counted with epifluorescent microscopy on standard aortic segments proximal and distal to the band. Immunohistochemistry was performed for the following antibodies: VCAM-1, RAM11, CD11b, and factor VIII.Mean blood pressure was 89 +/- 3 mm Hg in the aorta proximal to the stenosis, compared with 64 +/- 4 mm Hg in the no stenosis group and 74 +/- 3 mm Hg in the control group (p < 0.01). The mean aortic blood pressure gradient across the stenosis was 16 +/- 2 mm Hg in the stenosis group, whereas the aortic blood pressure gradient was 0.2 +/- 0.6 mm Hg in the no stenosis group and -0.3 +/- 0.4 mm Hg in the control group (p < 0.001). Monocyte adhesion to the aortic endothelial surface proximal to the stenosis was increased twofold compared with adhesion to the aorta distal to the stenosis and compared with the proximal aorta in the control group (p < 0.02). The proximal-to-distal aortic ratio of monocyte binding was enhanced in the stenosis group (2.2) compared with the no stenosis (0.76) and control (0.83) groups (p < 0.01). The intima area of the aorta proximal to the stenosis was significantly increased compared with the proximal aortas in the no stenosis and control groups (p < 0.01). RAM11, CD11b, and endothelial VCAM-1 expression were enhanced in the hypertensive region proximal to the stenosis.In the hypertensive region in the aorta proximal to the stenosis, monocyte adhesion and endothelial VCAM-1 expression were increased, with intimal thickening and accumulation of macrophages. These findings suggest that hypertension may promote atherosclerotic plaque formation by enhancing monocyte adhesion.

    View details for Web of Science ID A1996UJ12600010

    View details for PubMedID 8627894

  • Expression of inducible nitric oxide synthase fin human heart failure CIRCULATION Haywood, G. A., Tsao, P. S., VONDERLEYEN, H. E., Mann, M. J., Kelling, P. J., Trindade, P. T., Lewis, N. P., Byrne, C. D., Rickenbacher, P. R., Bishopric, N. H., Cooke, J. P., McKenna, W. J., Fowler, M. B. 1996; 93 (6): 1087-1094

    Abstract

    There is increasing evidence that alterations in nitric oxide synthesis are of pathophysiological importance in heart failure. A number of studies have shown altered nitric oxide production by the endothelial constitutive isoform of nitric oxide synthase (NOS), but there is very little information on the role of the inducible isoform.We analyzed inducible NOS (iNOS) expression in ventricular myocardium taken from 11 control subjects (who had died suddenly from noncardiac causes), from 10 donor hearts before implantation, and from 51 patients with heart failure (24 with dilated cardiomyopathy [DCM], 17 with ischemic heart disease [IHD], and 10 with valvular heart disease [VHD]). Reverse transcription-polymerase chain reaction was used to confirm the presence of intact mRNA and to detect expression of iNOS and atrial natriuretic peptide (ANP). ANP was used as a molecular phenotypic marker of ventricular failure. iNOS was expressed in 36 of 51 biopsies (71%) from patients with heart failure and in none of the control patients (P<.0001). iNOS expression could also be detected in 50% of the donor hearts. All samples that expressed iNOS also expressed ANP. iNOS gene expression occurred in 67% of patients with DCM, 59% of patients with IHD, and 100% of patients with VHD. To determine whether iNOS protein was expressed in failing ventricles, immunohistochemistry was performed on three donor hearts and nine failing hearts with iNOS mRNA expression. Staining for iNOS was almost undetectable in the donor myocardium and in control sections, but all failing hearts showed diffuse cytoplasmic staining in cardiac myocytes. Expression of iNOS could be observed in all four chambers. Western blot analysis with the same primary antibody showed a specific positive band for iNOS protein in the heart failure specimens; minimal iNOS protein expression was seen in donor heart samples.iNOS expression occurs in failing human cardiac myocytes and may be involved in the pathophysiology of DCM, IHD, and VHD.

    View details for Web of Science ID A1996UA05300006

    View details for PubMedID 8653828

  • Induction of nitric oxide synthase in the human cardiac allograft is associated with contractile dysfunction of the left ventricle CIRCULATION Lewis, N. P., Tsao, P. S., Rickenbacher, P. R., Xue, C., Johns, R. A., Haywood, G. A., VONDERLEYEN, H., Trindade, P. T., Cooke, J. P., Hunt, S. A., Billingham, M. E., Valantine, H. A., Fowler, M. B. 1996; 93 (4): 720-729

    Abstract

    The mechanisms underlying cardiac contractile dysfunction after transplantation remain poorly defined. Previous work has revealed that inducible nitric oxide synthase (iNOS) is expressed in the rat heterotopic cardiac allograft during rejection; resultant overproduction of nitric oxide (NO) might cause cardiac contractile dysfunction via the negative inotropic and cytotoxic actions of NO. In this investigation, we tested the hypothesis that induction of iNOS may occur and be associated with cardiac allograft contractile dysfunction in humans.We prospectively studied 16 patients in the first year after cardiac transplantation at the time of serial surveillance endomyocardial biopsy. Clinical data, the results of biopsy histology, and echocardiographic and Doppler evaluation of left ventricular systolic and diastolic function were recorded. Total RNA was extracted from biopsy specimens, and mRNA for beta-actin, detected by reverse transcription-polymerase chain reaction (RT-PCR) using human specific primers, was used as a constitutive gene control; iNOS mRNA was similarly detected by RT-PCR using human specific primers. iNOS protein was detected in biopsy frozen sections by immunofluorescence. Myocardial cGMP was measured by radioimmunoassay, and serum nitrogen oxide levels (NOx = NO2 + NO3) were measured by chemiluminescence. iNOS mRNA was detected in allograft myocardium at some point in each patient and in 59 of 123 biopsies (48%) overall. In individual patients, iNOS mRNA expression was episodic and time dependent; the frequency of expression was highest during the first 180 days after transplant (P = .0006). iNOS protein associated with iNOS mRNA was detected by immunofluorescence in cardiac myocytes. iNOS mRNA expression was not related to the ISHLT histological grade of rejection or to serum levels of NOx but was associated with increased levels of myocardial cGMP (P = .01) and with both systolic (P = .024) and diastolic (P = .006) left ventricular contractile dysfunction measured by echocardiography and Doppler.These data support a relation between iNOS mRNA expression and contractile dysfunction in the human cardiac allograft.

    View details for Web of Science ID A1996TV05300015

    View details for PubMedID 8641001

  • Regression or progression - Dependency on vascular nitric oxide ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Candipan, R. C., Wang, B. Y., Buitrago, R., Tsao, P. S., Cooke, J. P. 1996; 16 (1): 44-50

    Abstract

    We have shown that chronic administration of the nitric oxide (NO) precursor L-arginine inhibits atherogenesis in the hypercholesterolemic rabbit. However, the effect of supplemental arginine on preexisting lesions is not known and was the focus of the present study. New Zealand White rabbits received normal chow or 0.5% cholesterol chow for 10 weeks. Subsequently, L-arginine (2.25% in drinking water; ARG group) or vehicle (CHOL group) was administered for an additional 13 weeks, while the high-cholesterol diet was continued. Thoracic aortae were harvested at weeks 10, 14, 18, or 23. Rings of aorta were used to assess NO-dependent vasodilation to acetylcholine. Maximal relaxation to acetylcholine in the CHOL rabbits became progressively attenuated from 53.4% (at week 10) to 17.4% (by week 23). Planimetry of the luminal surface of the aortae from CHOL animals revealed a progressive increase in lesion surface area from 30.3% (at week 10) to 56.5% (by week 23). By contrast, animals in the ARG groups manifested improved endothelium-dependent relaxation associated with a reduction of lesion surface area at 14 and 18 weeks. The arginine-induced improvement in endothelium-dependent relaxation was associated with an increased generation of vascular NO and a reduced generation of vascular superoxide anion. By 23 weeks, 3 of 7 ARG animals had persistent improvement in NO-dependent vasodilation and exhibited a further reduction of lesion surface area tc 5.4%. We conclude that hypercholesterolemia induces a progressive loss of NO-dependent vasodilation associated with progressive intimal lesion formation. Administration of L-arginine to animals with preexisting intimal lesions augments vascular NO elaboration, reduces superoxide anion generation, and is associated with a reduction in lesion surface area. This is the first demonstration that restoration of NO activity can induce regression of preexisting intimal lesions and provides evidence that L-arginine therapy may be of potential clinical benefit.

    View details for Web of Science ID A1996TP12400006

    View details for PubMedID 8548425

  • Effects of felodipine on vascular structure, function and monocyte endothelial interaction in the hypercholesterolemic rabbit. Wang, B. Y., Niebauer, J., Singer, A. H., Tsao, P. S., Cooke, J. P. SLACK INC. 1996: A102
  • Felodipine inhibits intimal lesion formation in the hypercholesterolemic rabbit: differential effects on endothelial and monocyte determinants of atherogenesis. Vascular medicine Wang, B. Y., Niebauer, J., Singer, A. H., Tsao, P. S., Cooke, J. P. 1996; 1 (3): 173-179

    Abstract

    The purpose of this study was to determine if the calcium entry antagonist felodipine inhibited intimal lesion formation in hypercholesterolemic rabbits, and to determine if this was due to an effect upon monocyte and/or endothelial determinants of this interaction. Twenty-three male New Zealand White rabbits received the following treatment regimen for 10 weeks: normal chow (NP, n = 3); normal chow with felodipine infusion (NF, n = 6); 0.5% cholesterol chow (CP, n = 7); or 0.5% cholesterol chow and felodipine infusion (CF, n = 7). After 10 weeks blood was collected for biochemical measurements and mononuclear cell binding assays, and thoracic aortae were harvested for vascular reactivity studies and histomorphometry. In the animals receiving normal chow, felodipine did not significantly affect blood pressure, plasma cholesterol levels, binding studies, vascular reactivity, or structure; therefore these animals were analyzed as one group (N). Plasma cholesterol levels were significantly elevated in groups receiving the 0.5% cholesterol diet (N, 29 +/- 3 mg/dl; CP, 1221 +/- 73 mg/dl; CF, 979 +/- 108 mg/dl). High-density lipoprotein cholesterol was not different between the groups (25 +/- 4 vs 23 +/- 4 vs 27 +/- 4 mg/dl; N vs CF vs CP respectively; p = NS). Cholesterol feeding markedly augmented the adhesiveness of mononuclear cells, as demonstrated by a 250% increase in cell binding. Felodipine did not alter the adhesiveness of mononuclear cells in hypercholesterolemic animals. Cholesterol feeding significantly impaired endothelium-dependent relaxations. Endothelium-dependent relaxations were restored by felodipine treatment as reflected by the maximal responses to acetylcholine (40 +/- 7% vs 58 +/- 4% vs 67 +/- 5%; CP vs CF vs N respectively). The improvement in endothelium-dependent relaxation in the felodipine-treated animals was associated with a 2.2-fold reduction in lesion surface area of the thoracic aorta (8.2 +/- 6.3% vs 18.2 +/- 9.5%; CF vs CP; p < 0.01). Moreover, the intima/media ratio reflecting lesion thickness was substantially reduced by felodipine treatment (0.05 +/- 0.02 vs 0.20 +/- 0.07; CF vs CP; p = 0.006). Ex vivo studies revealed that felodipine inhibited the adhesiveness of vascular endothelium, but not mononuclear cells, derived from hypercholesterolemic animals. Low-dose felodipine appears to inhibit monocyte-endothelial interaction, as indicated by a reduction in the formation of lesions in hypercholesterolemic animals. This effect is not due to an alteration in adhesiveness of mononuclear cells. The salutary effect of felodipine is associated with an increase in vascular nitric oxide activity which may reduce endothelial adhesiveness.

    View details for PubMedID 9546935

  • EXPOSURE TO SHEAR-STRESS ALTERS ENDOTHELIAL ADHESIVENESS - ROLE OF NITRIC-OXIDE CIRCULATION Tsao, P. S., Lewis, N. P., Alpert, S., Cooke, J. P. 1995; 92 (12): 3513-3519

    Abstract

    Shear stress increases the release of nitric oxide (NO) by endothelial cells (ECs). We and others have provided evidence that endothelium-derived NO inhibits monocyte adhesion to the vessel wall. We therefore hypothesized that previous exposure to shear stress would inhibit endothelial adhesiveness for monocytes by virtue of its effect to increase NO release.Confluent monolayers of bovine aortic endothelial cells, human aortic endothelial cells, or human venous endothelial cells were exposed to laminar fluid flow. Culture media were collected for measurement of NO (by chemiluminescence) and the prostacyclin metabolite 6-keto-prostaglandin F1 alpha. NOx and 6-keto-prostaglandin F1 alpha accumulated in the conditioned medium during laminar fluid flow from 30 minutes to 24 hours in a time-dependent fashion. In another set of studies, ECs previously exposed to flow or to static conditions were washed with Hanks' buffer and exposed to THP-1 cells for 30 minutes. Adherent cells were counted by microscopy. Previous exposure to flow reduced endothelial adhesiveness for monocytes by 50% (P < .05). The effect of flow on endothelial adhesiveness occurred within 30 minutes. This effect was abrogated by nitro-L-arginine (an antagonist of NO synthesis), as well as by tetraethylammonium ion (an antagonist of the flow-activated potassium channel); the effects of these inhibitors were reversed by the NO donor SPM-5185. Although the cyclo-oxygenase inhibitor indomethacin totally inhibited the flow-induced production of prostacyclin by ECs, it minimally affected adherence of THP-1 cells. The early effect of flow on endothelial adhesiveness was not mediated by alterations in the expression of the endothelial adhesion molecules VCAM-1 or ICAM-1 as assessed by fluorescent activated cell sorting.Shear stress alters endothelial adhesiveness for monocytes; at early time points, this effect is largely due to flow-stimulated release of NO and, to a lesser extent, prostacyclin. This effect of flow occurs within 30 minutes and is probably due to alterations in the signal transduction or activation state (rather than the expression) of endothelial adhesion molecules.

    View details for Web of Science ID A1995TJ65500026

    View details for PubMedID 8521574

  • SUPEROXIDE GENERATION FROM ENDOTHELIAL-CELLS EXPOSED TO OXIDIZED LDL CAN BE REDUCED BY NITRIC-OXIDE SYNTHASE GENE-TRANSFER IN-VITRO Buitrago, R., VONDERLEYEN, H. E., Tsao, P. S., Mann, M. J., Gibbons, G. H., Cooke, J. P., Dzau, V. J. LIPPINCOTT WILLIAMS & WILKINS. 1995: 1733–33
  • GENETIC-ENGINEERING OF VEIN GRAFTS RESISTANT TO ATHEROSCLEROSIS PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Mann, M. J., Gibbons, G. H., Kernoff, R. S., DIET, F. P., Tsao, P. S., Cooke, J. P., Kaneda, Y., Dzau, V. J. 1995; 92 (10): 4502-4506

    Abstract

    Previously, researchers have speculated that genetic engineering can improve the long-term function of vascular grafts which are prone to atherosclerosis and occlusion. In this study, we demonstrated that an intraoperative gene therapy approach using antisense oligodeoxynucleotide blockage of medial smooth muscle cell proliferation can prevent the accelerated atherosclerosis that is responsible for autologous vein graft failure. Selective blockade of the expression of genes for two cell cycle regulatory proteins, proliferating cell nuclear antigen and cell division cycle 2 kinase, was achieved in the smooth muscle cells of rabbit jugular veins grafted into the carotid arteries. This alteration of gene expression successfully redirected vein graft biology away from neointimal hyperplasia and toward medial hypertrophy, yielding conduits that more closely resembled normal arteries. More importantly, these genetically engineered grafts proved resistant to diet-induced atherosclerosis. These findings establish the feasibility of developing genetically engineered bioprostheses that are resistant to failure and better suited to the long-term treatment of occlusive vascular disease.

    View details for Web of Science ID A1995QX87600085

    View details for PubMedID 7753833

    View details for PubMedCentralID PMC41972

  • DISCORDANT EFFECTS OF DIETARY L-ARGININE ON VASCULAR STRUCTURE AND REACTIVITY IN HYPERCHOLESTEROLEMIC RABBITS JOURNAL OF CARDIOVASCULAR PHARMACOLOGY Singer, A. H., Tsao, P. S., Wang, B. Y., Bloch, D. A., Cooke, J. P. 1995; 25 (5): 710-716

    Abstract

    We investigated the effect of dietary supplementation of L-arginine (L-Arg), the precursor of endothelial nitric oxide (NO), on endothelium-dependent and endothelium-independent vascular responses, as well as vascular structure, in the abdominal aorta of hypercholesterolemic rabbits. Rabbits were fed (a) normal rabbit chow, (b) 1% cholesterol diet, or (c) 1% cholesterol diet supplemented with 2.25% L-Arg HCl in drinking water. After 10 weeks, the abdominal aorta was harvested for study of vascular reactivity and histomorphometry. L-Arg did not affect serum cholesterol levels. Histomorphometric analysis demonstrated an eightfold reduction in intimal thickening in the abdominal aorta of the arginine-supplemented hypercholesterolemic rabbits. By contrast, the effects on vascular reactivity were subtle. Contraction to norepinephrine (NE) was not altered by hypercholesterolemia or L-Arg. Contraction to acetylcholine (ACh) was increased in hypercholesterolemic animals; this was normalized by dietary arginine supplementation. Relaxation to nitroglycerin (NTG) was not altered by hypercholesterolemia but was attenuated in the arginine-supplemented rabbits. Endothelium-dependent relaxation to ACh was impaired in both hypercholesterolemic groups. Dietary L-Arg has a dramatic antiatherogenic effect in hypercholesterolemic rabbits. This effect is associated with rather slight changes in vascular reactivity that are suggestive of a slight increase in NO elaboration by the endothelium. The discordance between the effects of dietary arginine on vascular structure and reactivity suggests that the antiatherogenic effects of the NO precursor may not be mediated entirely by its effect on the endothelium.

    View details for Web of Science ID A1995QV17000005

    View details for PubMedID 7630149

  • ENDOGENOUS AND EXOGENOUS NITRIC-OXIDE INHIBITS LIPID-INDUCED AND CYTOKINE-INDUCED MONOCYTE ADHESION TO ENDOTHELIAL-CELLS TSAO, P. S., WANG, B. Y., CHAN, COOKE, J. P. FEDERATION AMER SOC EXP BIOL. 1995: A37
  • L-ARGININE ATTENUATES PLATELET REACTIVITY IN HYPERCHOLESTEROLEMIC RABBITS ARTERIOSCLEROSIS AND THROMBOSIS Tsao, P. S., Theilmeier, G., Singer, A. H., Leung, L. L., Cooke, J. P. 1994; 14 (10): 1529-1533

    Abstract

    Platelets are capable of producing nitric oxide (NO) through the L-arginine-NO synthase pathway. Acute exposure to supraphysiological concentrations of L-arginine in vitro increases the production of NO by platelets and is associated with an increase in platelet cyclic GMP (cGMP) levels and a reduction in platelet aggregation. The purpose of this study was to determine if chronic oral administration of L-arginine decreases platelet aggregation in hypercholesterolemic animals and to determine if this effect is mediated by the metabolism of L-arginine to NO. Male New Zealand White rabbits were fed normal chow (Con), a 1% cholesterol diet (Chol), or a 1% cholesterol diet supplemented with a sixfold enrichment of dietary L-arginine (Arg) or L-methionine (Met). After 10 weeks, cholesterol levels were equally increased in Chol and Arg animals, whereas plasma arginine levels were doubled in the Arg group. There was no difference in maximum aggregation initiated by ADP (100 mumol/L) between washed platelets from Con, Met, and Chol animals, but aggregation of platelets from Arg animals was significantly decreased (P < .05). In aggregating platelets from Arg animals, cGMP levels were significantly higher than the other groups (P < .05). When platelets were incubated ex vivo with the NO synthase inhibitor NG-monomethyl-L-arginine, the effects of dietary L-arginine were reversed. Chronic dietary supplementation of L-arginine decreases platelet aggregation in hypercholesterolemic rabbits. This effect appears to be due to the metabolism of L-arginine to NO.

    View details for Web of Science ID A1994PL39400002

    View details for PubMedID 7918301

  • ENHANCED ENDOTHELIAL ADHESIVENESS IN HYPERCHOLESTEROLEMIA IS ATTENUATED BY L-ARGININE CIRCULATION Tsao, P. S., McEvoy, L. M., Drexler, H., BUTCHER, E. C., Cooke, J. P. 1994; 89 (5): 2176-2182

    Abstract

    We have shown that chronic administration of the nitric oxide (NO) precursor L-arginine normalizes NO-dependent vasodilation and markedly inhibits atherogenesis in a hypercholesterolemic rabbit model. We hypothesized that this antiatherogenic effect is due to modulation of endothelial adhesiveness by endothelium-derived NO.New Zealand White rabbits were fed normal chow (Cont), a high-cholesterol diet (Chol), a high-cholesterol diet supplemented with L-arginine (Arg), or a normal diet supplemented with the NO synthase antagonist L-nitroarginine (L-NA) for 2 weeks. In additional studies, some animals receiving L-NA were also treated with hydralazine to normalize blood pressure. After 2 weeks, thoracic aortas were harvested, opened longitudinally, and placed in a culture dish with the endothelial surface exposed to medium containing WEHI 78/24 cells, a monocytoid cell line. After incubation with the monocytoid cells for 30 minutes on a rocking platform, the aortic segments were washed repeatedly to remove nonadherent cells and adherent cells counted by epifluorescent microscopy. Monocytoid cell binding to aortic endothelium was significantly increased in Chol (P < .001 versus Cont); binding was markedly reduced in arginine-fed hypercholesterolemic animals (P < .05, Arg versus Chol). Monocytoid cell binding to aortic endothelium was also significantly increased in L-NA (P < .05); hydralazine normalized blood pressure but did not reduce monocytoid cell binding. To confirm that alterations in NO activity modulate endothelial cell-monocyte interaction, the release of nitrogen oxides (NOx) by thoracic aortas was assessed by a chemiluminescent technique. The concentration of NOx in the conditioned medium from segments of Arg thoracic aortas was significantly greater than that from Cont aortas, whereas that from L-NA aortas was significantly less.Hypercholesterolemia enhances the adhesiveness of aortic endothelium for monocytes; this effect is attenuated by dietary L-arginine. Conversely, inhibition of NO synthesis enhances monocyte binding. The results suggest that endothelium-derived NO plays an important role in regulating the endothelial adhesiveness for monocytes. Alterations in NO activity may play a critical role in atherogenesis.

    View details for Web of Science ID A1994NL67500034

    View details for PubMedID 8181143

  • DIETARY ARGININE ALTERS ENDOTHELIAL ADHESIVENESS VIA NO Tsao, P. S., Wang, B. Y., Cooke, J. P. SLACK INC. 1994: A175–A175
  • DIETARY ARGININE PREVENTS ATHEROGENESIS IN THE CORONARY-ARTERY OF THE HYPERCHOLESTEROLEMIC RABBIT JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Wang, B. Y., Singer, A. H., Tsao, P. S., Drexler, H., Kosek, J., Cooke, J. P. 1994; 23 (2): 452-458

    Abstract

    This study was designed to test the hypothesis that long-term oral supplementation of dietary L-arginine (to provide a sustained elevation of nitric oxide activity) would inhibit atherogenesis in hypercholesterolemic rabbits, as assessed by histomorphometric measurements.Endothelium-derived nitric oxide inhibits a number of processes that are critical in atherogenesis. Hypercholesterolemia reduces endothelial nitric oxide activity, and we postulate that this may promote atherogenesis. This reduction in nitric oxide activity can be reversed acutely by intravenous infusion of L-arginine, the precursor of nitric oxide. We show that dietary supplementation of L-arginine abrogates the development of coronary atheroma in hypercholesterolemic rabbits.Male New Zealand White rabbits were fed normal rabbit chow, 1% cholesterol chow or 1% cholesterol chow with dietary arginine or methionine supplementation to increase their intake of these amino acids sixfold. After 1 or 10 weeks of dietary intervention, the left main and left anterior descending coronary arteries were harvested for histologic study. Plasma cholesterol measurements were elevated to the same degree in all groups of rabbits receiving the 1% cholesterol diet, whereas plasma arginine levels were doubled in the arginine-treated group. High density lipoprotein (HDL) cholesterol values were not affected by arginine treatment.In rabbits receiving the 1% cholesterol diet, with or without methionine supplementation, light and electron microscopy revealed a marked increase from 1 to 10 weeks in the intimal accumulation of macrophages, associated with an increase in the intimal area of the left main coronary artery. By contrast, in arginine-treated hypercholesterolemic rabbits, there was a near absence of adherent monocytes and tissue macrophages and no progression of intimal thickness from 1 to 10 weeks.Dietary supplements of L-arginine prevent intimal thickening in the coronary arteries of hypercholesterolemic rabbits. This antiatherogenic effect is not due to an alteration in plasma total cholesterol, HDL cholesterol or caloric or nitrogen balance. The data are consistent with the hypothesis that nitric oxide has antiatherogenic properties.

    View details for Web of Science ID A1994NR75200026

    View details for PubMedID 8294700

  • DIETARY L-ARGININE REDUCES PLATELET REACTIVITY IN HYPERCHOLESTEROLEMIC RABBITS Tsao, P. S., Singer, A. H., Ohno, M., Kaplan, A. V., Leung, L., Cooke, J. P. SLACK INC. 1993: A78–A78
  • The role of endothelial dysfunction in restenosis. Revista portuguesa de cardiologia Cooke, J. P., Tsao, P. S. 1992; 11 (10): 889-892

    View details for PubMedID 1285965

  • CELLULAR MECHANISMS OF ATHEROGENESIS AND THE EFFECTS OF NITRIC-OXIDE CURRENT OPINION IN CARDIOLOGY Cooke, J. P., Tsao, P. 1992; 7 (5): 799-804
  • ANTIATHEROGENIC EFFECTS OF L-ARGININE IN THE HYPERCHOLESTEROLEMIC RABBIT JOURNAL OF CLINICAL INVESTIGATION Cooke, J. P., Singer, A. H., Tsao, P., ZERA, P., Rowan, R. A., Billingham, M. E. 1992; 90 (3): 1168-1172

    Abstract

    The purpose of this study was to determine if chronic administration of L-arginine, the precursor of endothelium-derived relaxing factor (EDRF), normalizes endothelium-dependent relaxation and decreases atherosclerosis in hypercholesterolemic animals. Male rabbits were fed (a) normal rabbit chow; (b) 1% cholesterol diet; or (c) 1% cholesterol diet supplemented by 2.25% L-arginine HCl in drinking water. Arginine supplementation doubled plasma arginine levels without affecting serum cholesterol values. After 10 wk, the thoracic aorta was harvested for studies of vascular reactivity and histomorphometry. Endothelium-dependent relaxations (to acetylcholine and calcium ionophore A23187) were significantly impaired in thoracic aortae from animals fed a 1% cholesterol diet. By contrast, vessels from hypercholesterolemic animals receiving L-arginine supplementation exhibited significantly improved endothelium-dependent relaxations. Responses to norepinephrine or nitroglycerin were not affected by either dietary intervention. Histomorphometric analysis revealed a reduction in lesion surface area and intimal thickness in thoracic aortae from arginine-supplemented animals compared to those from untreated hypercholesterolemic rabbits. This is the first study to demonstrate that supplementation of dietary L-arginine, the EDRF precursor, improves endothelium-dependent vasorelaxation. More importantly, we have shown that this improvement in EDRF activity is associated with a reduction in atherogenesis.

    View details for Web of Science ID A1992JN95900065

    View details for PubMedID 1522225