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Find video protocols related to scientific articles indexed in Pubmed.
Defining the role of common variation in the genomic and biological architecture of adult human height.
Andrew R Wood, Tonu Esko, Jian Yang, Sailaja Vedantam, Tune H Pers, Stefan Gustafsson, Audrey Y Chu, Karol Estrada, Jian'an Luan, Zoltan Kutalik, Najaf Amin, Martin L Buchkovich, Damien C Croteau-Chonka, Felix R Day, Yanan Duan, Tove Fall, Rudolf Fehrmann, Teresa Ferreira, Anne U Jackson, Juha Karjalainen, Ken Sin Lo, Adam E Locke, Reedik Mägi, Evelin Mihailov, Eleonora Porcu, Joshua C Randall, André Scherag, Anna A E Vinkhuyzen, Harm-Jan Westra, Thomas W Winkler, Tsegaselassie Workalemahu, Jing Hua Zhao, Devin Absher, Eva Albrecht, Denise Anderson, Jeffrey Baron, Marian Beekman, Ayse Demirkan, Georg B Ehret, Bjarke Feenstra, Mary F Feitosa, Krista Fischer, Ross M Fraser, Anuj Goel, Jian Gong, Anne E Justice, Stavroula Kanoni, Marcus E Kleber, Kati Kristiansson, Unhee Lim, Vaneet Lotay, Julian C Lui, Massimo Mangino, Irene Mateo Leach, Carolina Medina-Gomez, Michael A Nalls, Dale R Nyholt, Cameron D Palmer, Dorota Pasko, Sonali Pechlivanis, Inga Prokopenko, Janina S Ried, Stephan Ripke, Dmitry Shungin, Alena Stančáková, Rona J Strawbridge, Yun Ju Sung, Toshiko Tanaka, Alexander Teumer, Stella Trompet, Sander W van der Laan, Jessica van Setten, Jana V van Vliet-Ostaptchouk, Zhaoming Wang, Loïc Yengo, Weihua Zhang, Uzma Afzal, Johan Arnlöv, Gillian M Arscott, Stefania Bandinelli, Amy Barrett, Claire Bellis, Amanda J Bennett, Christian Berne, Matthias Blüher, Jennifer L Bolton, Yvonne Böttcher, Heather A Boyd, Marcel Bruinenberg, Brendan M Buckley, Steven Buyske, Ida H Caspersen, Peter S Chines, Robert Clarke, Simone Claudi-Boehm, Matthew Cooper, E Warwick Daw, Pim A de Jong, Joris Deelen, Graciela Delgado, Josh C Denny, Rosalie Dhonukshe-Rutten, Maria Dimitriou, Alex S F Doney, Marcus Dörr, Niina Eklund, Elodie Eury, Lasse Folkersen, Melissa E Garcia, Frank Geller, Vilmantas Giedraitis, Alan S Go, Harald Grallert, Tanja B Grammer, Jürgen Gräßler, Henrik Grönberg, Lisette C P G M de Groot, Christopher J Groves, Jeffrey Haessler, Per Hall, Toomas Haller, Göran Hallmans, Anke Hannemann, Catharina A Hartman, Maija Hassinen, Caroline Hayward, Nancy L Heard-Costa, Quinta Helmer, Gibran Hemani, Anjali K Henders, Hans L Hillege, Mark A Hlatky, Wolfgang Hoffmann, Per Hoffmann, Oddgeir Holmen, Jeanine J Houwing-Duistermaat, Thomas Illig, Aaron Isaacs, Alan L James, Janina Jeff, Berit Johansen, Asa Johansson, Jennifer Jolley, Thorhildur Juliusdottir, Juhani Junttila, Abel N Kho, Leena Kinnunen, Norman Klopp, Thomas Kocher, Wolfgang Kratzer, Peter Lichtner, Lars Lind, Jaana Lindström, Stéphane Lobbens, Mattias Lorentzon, Yingchang Lu, Valeriya Lyssenko, Patrik K E Magnusson, Anubha Mahajan, Marc Maillard, Wendy L McArdle, Colin A McKenzie, Stela McLachlan, Paul J McLaren, Cristina Menni, Sigrun Merger, Lili Milani, Alireza Moayyeri, Keri L Monda, Mario A Morken, Gabriele Müller, Martina Müller-Nurasyid, Arthur W Musk, Narisu Narisu, Matthias Nauck, Ilja M Nolte, Markus M Nöthen, Laticia Oozageer, Stefan Pilz, Nigel W Rayner, Frida Renstrom, Neil R Robertson, Lynda M Rose, Ronan Roussel, Serena Sanna, Hubert Scharnagl, Salome Scholtens, Fredrick R Schumacher, Heribert Schunkert, Robert A Scott, Joban Sehmi, Thomas Seufferlein, Jianxin Shi, Karri Silventoinen, Johannes H Smit, Albert Vernon Smith, Joanna Smolonska, Alice V Stanton, Kathleen Stirrups, David J Stott, Heather M Stringham, Johan Sundström, Morris A Swertz, Ann-Christine Syvänen, Bamidele O Tayo, Gudmar Thorleifsson, Jonathan P Tyrer, Suzanne van Dijk, Natasja M van Schoor, Nathalie van der Velde, Diana van Heemst, Floor V A van Oort, Sita H Vermeulen, Niek Verweij, Judith M Vonk, Lindsay L Waite, Melanie Waldenberger, Roman Wennauer, Lynne R Wilkens, Christina Willenborg, Tom Wilsgaard, Mary K Wojczynski, Andrew Wong, Alan F Wright, Qunyuan Zhang, Dominique Arveiler, Stephan J L Bakker, John Beilby, Richard N Bergman, Sven Bergmann, Reiner Biffar, John Blangero, Dorret I Boomsma, Stefan R Bornstein, Pascal Bovet, Paolo Brambilla, Morris J Brown, Harry Campbell, Mark J Caulfield, Aravinda Chakravarti, Rory Collins, Francis S Collins, Dana C Crawford, L Adrienne Cupples, John Danesh, Ulf de Faire, Hester M den Ruijter, Raimund Erbel, Jeanette Erdmann, Johan G Eriksson, Martin Farrall, Ele Ferrannini, Jean Ferrières, Ian Ford, Nita G Forouhi, Terrence Forrester, Ron T Gansevoort, Pablo V Gejman, Christian Gieger, Alain Golay, Omri Gottesman, Vilmundur Gudnason, Ulf Gyllensten, David W Haas, Alistair S Hall, Tamara B Harris, Andrew T Hattersley, Andrew C Heath, Christian Hengstenberg, Andrew A Hicks, Lucia A Hindorff, Aroon D Hingorani, Albert Hofman, G Kees Hovingh, Steve E Humphries, Steven C Hunt, Elina Hyppönen, Kevin B Jacobs, Marjo-Riitta Järvelin, Pekka Jousilahti, Antti M Jula, Jaakko Kaprio, John J P Kastelein, Manfred Kayser, Frank Kee, Sirkka M Keinanen-Kiukaanniemi, Lambertus A Kiemeney, Jaspal S Kooner, Charles Kooperberg, Seppo Koskinen, Peter Kovacs, Aldi T Kraja, Meena Kumari, Johanna Kuusisto, Timo A Lakka, Claudia Langenberg, Loic Le Marchand, Terho Lehtimäki, Sara Lupoli, Pamela A F Madden, Satu Mannisto, Paolo Manunta, André Marette, Tara C Matise, Barbara McKnight, Thomas Meitinger, Frans L Moll, Grant W Montgomery, Andrew D Morris, Andrew P Morris, Jeffrey C Murray, Mari Nelis, Claes Ohlsson, Albertine J Oldehinkel, Ken K Ong, Willem H Ouwehand, Gerard Pasterkamp, Annette Peters, Peter P Pramstaller, Jackie F Price, Lu Qi, Olli T Raitakari, Tuomo Rankinen, D C Rao, Treva K Rice, Marylyn Ritchie, Igor Rudan, Veikko Salomaa, Nilesh J Samani, Jouko Saramies, Mark A Sarzynski, Peter E H Schwarz, Sylvain Sebert, Peter Sever, Alan R Shuldiner, Juha Sinisalo, Valgerdur Steinthorsdottir, Ronald P Stolk, Jean-Claude Tardif, Anke Tönjes, Angelo Tremblay, Elena Tremoli, Jarmo Virtamo, Marie-Claude Vohl, , Philippe Amouyel, Folkert W Asselbergs, Themistocles L Assimes, Murielle Bochud, Bernhard O Boehm, Eric Boerwinkle, Erwin P Bottinger, Claude Bouchard, Stéphane Cauchi, John C Chambers, Stephen J Chanock, Richard S Cooper, Paul I W de Bakker, George Dedoussis, Luigi Ferrucci, Paul W Franks, Philippe Froguel, Leif C Groop, Christopher A Haiman, Anders Hamsten, M Geoffrey Hayes, Jennie Hui, David J Hunter, Kristian Hveem, J Wouter Jukema, Robert C Kaplan, Mika Kivimäki, Diana Kuh, Markku Laakso, Yongmei Liu, Nicholas G Martin, Winfried März, Mads Melbye, Susanne Moebus, Patricia B Munroe, Inger Njølstad, Ben A Oostra, Colin N A Palmer, Nancy L Pedersen, Markus Perola, Louis Pérusse, Ulrike Peters, Joseph E Powell, Chris Power, Thomas Quertermous, Rainer Rauramaa, Eva Reinmaa, Paul M Ridker, Fernando Rivadeneira, Jerome I Rotter, Timo E Saaristo, Danish Saleheen, David Schlessinger, P Eline Slagboom, Harold Snieder, Tim D Spector, Konstantin Strauch, Michael Stumvoll, Jaakko Tuomilehto, Matti Uusitupa, Pim van der Harst, Henry Völzke, Mark Walker, Nicholas J Wareham, Hugh Watkins, H-Erich Wichmann, James F Wilson, Pieter Zanen, Panos Deloukas, Iris M Heid, Cecilia M Lindgren, Karen L Mohlke, Elizabeth K Speliotes, Unnur Thorsteinsdottir, Inês Barroso, Caroline S Fox, Kari E North, David P Strachan, Jacques S Beckmann, Sonja I Berndt, Michael Boehnke, Ingrid B Borecki, Mark I McCarthy, Andres Metspalu, Kari Stefansson, André G Uitterlinden, Cornelia M van Duijn, Lude Franke, Cristen J Willer, Alkes L Price, Guillaume Lettre, Ruth J F Loos, Michael N Weedon, Erik Ingelsson, Jeffrey R O'Connell, Gonçalo R Abecasis, Daniel I Chasman, Michael E Goddard, Peter M Visscher, Joel N Hirschhorn, Timothy M Frayling.
Nat. Genet.
PUBLISHED: 08-29-2014
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Using genome-wide data from 253,288 individuals, we identified 697 variants at genome-wide significance that together explained one-fifth of the heritability for adult height. By testing different numbers of variants in independent studies, we show that the most strongly associated ?2,000, ?3,700 and ?9,500 SNPs explained ?21%, ?24% and ?29% of phenotypic variance. Furthermore, all common variants together captured 60% of heritability. The 697 variants clustered in 423 loci were enriched for genes, pathways and tissue types known to be involved in growth and together implicated genes and pathways not highlighted in earlier efforts, such as signaling by fibroblast growth factors, WNT/?-catenin and chondroitin sulfate-related genes. We identified several genes and pathways not previously connected with human skeletal growth, including mTOR, osteoglycin and binding of hyaluronic acid. Our results indicate a genetic architecture for human height that is characterized by a very large but finite number (thousands) of causal variants.
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A long noncoding RNA protects the heart from pathological hypertrophy.
Nature
PUBLISHED: 08-10-2014
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The role of long noncoding RNA (lncRNA) in adult hearts is unknown; also unclear is how lncRNA modulates nucleosome remodelling. An estimated 70% of mouse genes undergo antisense transcription, including myosin heavy chain 7 (Myh7), which encodes molecular motor proteins for heart contraction. Here we identify a cluster of lncRNA transcripts from Myh7 loci and demonstrate a new lncRNA-chromatin mechanism for heart failure. In mice, these transcripts, which we named myosin heavy-chain-associated RNA transcripts (Myheart, or Mhrt), are cardiac-specific and abundant in adult hearts. Pathological stress activates the Brg1-Hdac-Parp chromatin repressor complex to inhibit Mhrt transcription in the heart. Such stress-induced Mhrt repression is essential for cardiomyopathy to develop: restoring Mhrt to the pre-stress level protects the heart from hypertrophy and failure. Mhrt antagonizes the function of Brg1, a chromatin-remodelling factor that is activated by stress to trigger aberrant gene expression and cardiac myopathy. Mhrt prevents Brg1 from recognizing its genomic DNA targets, thus inhibiting chromatin targeting and gene regulation by Brg1. It does so by binding to the helicase domain of Brg1, a domain that is crucial for tethering Brg1 to chromatinized DNA targets. Brg1 helicase has dual nucleic-acid-binding specificities: it is capable of binding lncRNA (Mhrt) and chromatinized--but not naked--DNA. This dual-binding feature of helicase enables a competitive inhibition mechanism by which Mhrt sequesters Brg1 from its genomic DNA targets to prevent chromatin remodelling. A Mhrt-Brg1 feedback circuit is thus crucial for heart function. Human MHRT also originates from MYH7 loci and is repressed in various types of myopathic hearts, suggesting a conserved lncRNA mechanism in human cardiomyopathy. Our studies identify a cardioprotective lncRNA, define a new targeting mechanism for ATP-dependent chromatin-remodelling factors, and establish a new paradigm for lncRNA-chromatin interaction.
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Integrative genomics reveals novel molecular pathways and gene networks for coronary artery disease.
PLoS Genet.
PUBLISHED: 07-01-2014
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The majority of the heritability of coronary artery disease (CAD) remains unexplained, despite recent successes of genome-wide association studies (GWAS) in identifying novel susceptibility loci. Integrating functional genomic data from a variety of sources with a large-scale meta-analysis of CAD GWAS may facilitate the identification of novel biological processes and genes involved in CAD, as well as clarify the causal relationships of established processes. Towards this end, we integrated 14 GWAS from the CARDIoGRAM Consortium and two additional GWAS from the Ottawa Heart Institute (25,491 cases and 66,819 controls) with 1) genetics of gene expression studies of CAD-relevant tissues in humans, 2) metabolic and signaling pathways from public databases, and 3) data-driven, tissue-specific gene networks from a multitude of human and mouse experiments. We not only detected CAD-associated gene networks of lipid metabolism, coagulation, immunity, and additional networks with no clear functional annotation, but also revealed key driver genes for each CAD network based on the topology of the gene regulatory networks. In particular, we found a gene network involved in antigen processing to be strongly associated with CAD. The key driver genes of this network included glyoxalase I (GLO1) and peptidylprolyl isomerase I (PPIL1), which we verified as regulatory by siRNA experiments in human aortic endothelial cells. Our results suggest genetic influences on a diverse set of both known and novel biological processes that contribute to CAD risk. The key driver genes for these networks highlight potential novel targets for further mechanistic studies and therapeutic interventions.
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Oxido-reductive regulation of vascular remodeling by receptor tyrosine kinase ROS1.
J. Clin. Invest.
PUBLISHED: 06-09-2014
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Angioplasty and stenting is the primary treatment for flow-limiting atherosclerosis; however, this strategy is limited by pathological vascular remodeling. Using a systems approach, we identified a role for the network hub gene glutathione peroxidase-1 (GPX1) in pathological remodeling following human blood vessel stenting. Constitutive deletion of Gpx1 in atherosclerotic mice recapitulated this phenotype of increased vascular smooth muscle cell (VSMC) proliferation and plaque formation. In an independent patient cohort, gene variant pair analysis identified an interaction of GPX1 with the orphan protooncogene receptor tyrosine kinase ROS1. A meta-analysis of the only genome-wide association studies of human neointima-induced in-stent stenosis confirmed the association of the ROS1 variant with pathological remodeling. Decreased GPX1 expression in atherosclerotic mice led to reductive stress via a time-dependent increase in glutathione, corresponding to phosphorylation of the ROS1 kinase activation site Y2274. Loss of GPX1 function was associated with both oxidative and reductive stress, the latter driving ROS1 activity via s-glutathiolation of critical residues of the ROS1 tyrosine phosphatase SHP-2. ROS1 inhibition with crizotinib and deglutathiolation of SHP-2 abolished GPX1-mediated increases in VSMC proliferation while leaving endothelialization intact. Our results indicate that GPX1-dependent alterations in oxido-reductive stress promote ROS1 activation and mediate vascular remodeling.
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Dissecting the causal genetic mechanisms of coronary heart disease.
Curr Atheroscler Rep
PUBLISHED: 03-14-2014
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Large-scale genome-wide association studies (GWAS) have identified 46 loci that are associated with coronary heart disease (CHD). Additionally, 104 independent candidate variants (false discovery rate of 5 %) have been identified (Schunkert H, Konig IR, Kathiresan S, Reilly MP, Assimes TL, Holm H et al. Nat Genet 43:333-8, 2011; Deloukas P, Kanoni S, Willenborg C, Farrall M, Assimes TL, Thompson JR et al. Nat Genet 45:25-33, 2012; C4D Genetics Consortium. Nat Genet 43:339-44, 2011). The majority of the causal genes in these loci function independently of conventional risk factors. It is postulated that a number of the CHD-associated genes regulate basic processes in the vascular cells involved in atherosclerosis, and that study of the signaling pathways that are modulated in this cell type by causal regulatory variation will provide critical new insights for targeting the initiation and progression of disease. In this review, we will discuss the types of experimental approaches and data that are critical to understanding the molecular processes that underlie the disease risk at 9p21.3, TCF21, SORT1, and other CHD-associated loci.
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Coronary heart disease-associated variation in TCF21 disrupts a miR-224 binding site and miRNA-mediated regulation.
PLoS Genet.
PUBLISHED: 03-01-2014
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Genome-wide association studies (GWAS) have identified chromosomal loci that affect risk of coronary heart disease (CHD) independent of classical risk factors. One such association signal has been identified at 6q23.2 in both Caucasians and East Asians. The lead CHD-associated polymorphism in this region, rs12190287, resides in the 3' untranslated region (3'-UTR) of TCF21, a basic-helix-loop-helix transcription factor, and is predicted to alter the seed binding sequence for miR-224. Allelic imbalance studies in circulating leukocytes and human coronary artery smooth muscle cells (HCASMC) showed significant imbalance of the TCF21 transcript that correlated with genotype at rs12190287, consistent with this variant contributing to allele-specific expression differences. 3' UTR reporter gene transfection studies in HCASMC showed that the disease-associated C allele has reduced expression compared to the protective G allele. Kinetic analyses in vitro revealed faster RNA-RNA complex formation and greater binding of miR-224 with the TCF21 C allelic transcript. In addition, in vitro probing with Pb2+ and RNase T1 revealed structural differences between the TCF21 variants in proximity of the rs12190287 variant, which are predicted to provide greater access to the C allele for miR-224 binding. miR-224 and TCF21 expression levels were anti-correlated in HCASMC, and miR-224 modulates the transcriptional response of TCF21 to transforming growth factor-? (TGF-?) and platelet derived growth factor (PDGF) signaling in an allele-specific manner. Lastly, miR-224 and TCF21 were localized in human coronary artery lesions and anti-correlated during atherosclerosis. Together, these data suggest that miR-224 interaction with the TCF21 transcript contributes to allelic imbalance of this gene, thus partly explaining the genetic risk for coronary heart disease associated at 6q23.2. These studies implicating rs12190287 in the miRNA-dependent regulation of TCF21, in conjunction with previous studies showing that this variant modulates transcriptional regulation through activator protein 1 (AP-1), suggests a unique bimodal level of complexity previously unreported for disease-associated variants.
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Linkage analysis incorporating gene-age interactions identifies seven novel lipid loci: the Family Blood Pressure Program.
Atherosclerosis
PUBLISHED: 01-06-2014
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To detect novel loci with age-dependent effects on fasting (? 8 h) levels of total cholesterol, high-density lipoprotein, low-density lipoprotein, and triglycerides using 3600 African Americans, 1283 Asians, 3218 European Americans, and 2026 Mexican Americans from the Family Blood Pressure Program (FBPP).
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Insulin resistance: regression and clustering.
PLoS ONE
PUBLISHED: 01-01-2014
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In this paper we try to define insulin resistance (IR) precisely for a group of Chinese women. Our definition deliberately does not depend upon body mass index (BMI) or age, although in other studies, with particular random effects models quite different from models used here, BMI accounts for a large part of the variability in IR. We accomplish our goal through application of Gauss mixture vector quantization (GMVQ), a technique for clustering that was developed for application to lossy data compression. Defining data come from measurements that play major roles in medical practice. A precise statement of what the data are is in Section 1. Their family structures are described in detail. They concern levels of lipids and the results of an oral glucose tolerance test (OGTT). We apply GMVQ to residuals obtained from regressions of outcomes of an OGTT and lipids on functions of age and BMI that are inferred from the data. A bootstrap procedure developed for our family data supplemented by insights from other approaches leads us to believe that two clusters are appropriate for defining IR precisely. One cluster consists of women who are IR, and the other of women who seem not to be. Genes and other features are used to predict cluster membership. We argue that prediction with "main effects" is not satisfactory, but prediction that includes interactions may be.
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The combination of 9p21.3 genotype and biomarker profile improves a peripheral artery disease risk prediction model.
Vasc Med
PUBLISHED: 12-09-2013
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Peripheral artery disease (PAD) is a highly morbid condition affecting more than 8 million Americans. Frequently, PAD patients are unrecognized and therefore do not receive appropriate therapies. Therefore, new methods to identify PAD have been pursued, but have thus far had only modest success. Here we describe a new approach combining genomic and metabolic information to enhance the diagnosis of PAD. We measured the genotype of the chromosome 9p21 cardiovascular-risk polymorphism rs10757269 as well as the biomarkers C-reactive protein, cystatin C, ?2-microglobulin, and plasma glucose in a study population of 393 patients undergoing coronary angiography. The rs10757269 allele was associated with PAD status (ankle-brachial index < 0.9) independent of biomarkers and traditional cardiovascular risk factors (odds ratio=1.92; 95% confidence interval, 1.29-2.85). Importantly, compared to a previously validated risk factor-based PAD prediction model, the addition of biomarkers and rs10757269 significantly and incrementally improved PAD risk prediction as assessed by the net reclassification index (NRI=33.5%; p=0.001) and integrated discrimination improvement (IDI=0.016; p=0.017). In conclusion, a model including a panel of biomarkers, which includes both genomic information (which is reflective of heritable risk) and metabolic information (which integrates environmental exposures), predicts the presence or absence of PAD better than established risk models, suggesting clinical utility for the diagnosis of PAD.
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Discovery and refinement of loci associated with lipid levels.
, Cristen J Willer, Ellen M Schmidt, Sebanti Sengupta, Gina M Peloso, Stefan Gustafsson, Stavroula Kanoni, Andrea Ganna, Jin Chen, Martin L Buchkovich, Samia Mora, Jacques S Beckmann, Jennifer L Bragg-Gresham, Hsing-Yi Chang, Ayse Demirkan, Heleen M den Hertog, Ron Do, Louise A Donnelly, Georg B Ehret, Tonu Esko, Mary F Feitosa, Teresa Ferreira, Krista Fischer, Pierre Fontanillas, Ross M Fraser, Daniel F Freitag, Deepti Gurdasani, Kauko Heikkilä, Elina Hyppönen, Aaron Isaacs, Anne U Jackson, Asa Johansson, Toby Johnson, Marika Kaakinen, Johannes Kettunen, Marcus E Kleber, Xiaohui Li, Jian'an Luan, Leo-Pekka Lyytikäinen, Patrik K E Magnusson, Massimo Mangino, Evelin Mihailov, May E Montasser, Martina Müller-Nurasyid, Ilja M Nolte, Jeffrey R O'Connell, Cameron D Palmer, Markus Perola, Ann-Kristin Petersen, Serena Sanna, Richa Saxena, Susan K Service, Sonia Shah, Dmitry Shungin, Carlo Sidore, Ci Song, Rona J Strawbridge, Ida Surakka, Toshiko Tanaka, Tanya M Teslovich, Gudmar Thorleifsson, Evita G van den Herik, Benjamin F Voight, Kelly A Volcik, Lindsay L Waite, Andrew Wong, Ying Wu, Weihua Zhang, Devin Absher, Gershim Asiki, Inês Barroso, Latonya F Been, Jennifer L Bolton, Lori L Bonnycastle, Paolo Brambilla, Mary S Burnett, Giancarlo Cesana, Maria Dimitriou, Alex S F Doney, Angela Döring, Paul Elliott, Stephen E Epstein, Gudmundur Ingi Eyjolfsson, Bruna Gigante, Mark O Goodarzi, Harald Grallert, Martha L Gravito, Christopher J Groves, Göran Hallmans, Anna-Liisa Hartikainen, Caroline Hayward, Dena Hernandez, Andrew A Hicks, Hilma Holm, Yi-Jen Hung, Thomas Illig, Michelle R Jones, Pontiano Kaleebu, John J P Kastelein, Kay-Tee Khaw, Eric Kim, Norman Klopp, Pirjo Komulainen, Meena Kumari, Claudia Langenberg, Terho Lehtimäki, Shih-Yi Lin, Jaana Lindström, Ruth J F Loos, François Mach, Wendy L McArdle, Christa Meisinger, Braxton D Mitchell, Gabrielle Müller, Ramaiah Nagaraja, Narisu Narisu, Tuomo V M Nieminen, Rebecca N Nsubuga, Isleifur Olafsson, Ken K Ong, Aarno Palotie, Theodore Papamarkou, Cristina Pomilla, Anneli Pouta, Daniel J Rader, Muredach P Reilly, Paul M Ridker, Fernando Rivadeneira, Igor Rudan, Aimo Ruokonen, Nilesh Samani, Hubert Scharnagl, Janet Seeley, Kaisa Silander, Alena Stančáková, Kathleen Stirrups, Amy J Swift, Laurence Tiret, André G Uitterlinden, L Joost van Pelt, Sailaja Vedantam, Nicholas Wainwright, Cisca Wijmenga, Sarah H Wild, Gonneke Willemsen, Tom Wilsgaard, James F Wilson, Elizabeth H Young, Jing Hua Zhao, Linda S Adair, Dominique Arveiler, Themistocles L Assimes, Stefania Bandinelli, Franklyn Bennett, Murielle Bochud, Bernhard O Boehm, Dorret I Boomsma, Ingrid B Borecki, Stefan R Bornstein, Pascal Bovet, Michel Burnier, Harry Campbell, Aravinda Chakravarti, John C Chambers, Yii-Der Ida Chen, Francis S Collins, Richard S Cooper, John Danesh, George Dedoussis, Ulf de Faire, Alan B Feranil, Jean Ferrières, Luigi Ferrucci, Nelson B Freimer, Christian Gieger, Leif C Groop, Vilmundur Gudnason, Ulf Gyllensten, Anders Hamsten, Tamara B Harris, Aroon Hingorani, Joel N Hirschhorn, Albert Hofman, G Kees Hovingh, Chao Agnes Hsiung, Steve E Humphries, Steven C Hunt, Kristian Hveem, Carlos Iribarren, Marjo-Riitta Järvelin, Antti Jula, Mika Kähönen, Jaakko Kaprio, Antero Kesäniemi, Mika Kivimäki, Jaspal S Kooner, Peter J Koudstaal, Ronald M Krauss, Diana Kuh, Johanna Kuusisto, Kirsten O Kyvik, Markku Laakso, Timo A Lakka, Lars Lind, Cecilia M Lindgren, Nicholas G Martin, Winfried März, Mark I McCarthy, Colin A McKenzie, Pierre Meneton, Andres Metspalu, Leena Moilanen, Andrew D Morris, Patricia B Munroe, Inger Njølstad, Nancy L Pedersen, Chris Power, Peter P Pramstaller, Jackie F Price, Bruce M Psaty, Thomas Quertermous, Rainer Rauramaa, Danish Saleheen, Veikko Salomaa, Dharambir K Sanghera, Jouko Saramies, Peter E H Schwarz, Wayne H-H Sheu, Alan R Shuldiner, Agneta Siegbahn, Tim D Spector, Kari Stefansson, David P Strachan, Bamidele O Tayo, Elena Tremoli, Jaakko Tuomilehto, Matti Uusitupa, Cornelia M van Duijn, Peter Vollenweider, Lars Wallentin, Nicholas J Wareham, John B Whitfield, Bruce H R Wolffenbuttel, José M Ordovás, Eric Boerwinkle, Colin N A Palmer, Unnur Thorsteinsdottir, Daniel I Chasman, Jerome I Rotter, Paul W Franks, Samuli Ripatti, L Adrienne Cupples, Manjinder S Sandhu, Stephen S Rich, Michael Boehnke, Panos Deloukas, Sekar Kathiresan, Karen L Mohlke, Erik Ingelsson, Gonçalo R Abecasis.
Nat. Genet.
PUBLISHED: 09-13-2013
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Levels of low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides and total cholesterol are heritable, modifiable risk factors for coronary artery disease. To identify new loci and refine known loci influencing these lipids, we examined 188,577 individuals using genome-wide and custom genotyping arrays. We identify and annotate 157 loci associated with lipid levels at P < 5 × 10(-8), including 62 loci not previously associated with lipid levels in humans. Using dense genotyping in individuals of European, East Asian, South Asian and African ancestry, we narrow association signals in 12 loci. We find that loci associated with blood lipid levels are often associated with cardiovascular and metabolic traits, including coronary artery disease, type 2 diabetes, blood pressure, waist-hip ratio and body mass index. Our results demonstrate the value of using genetic data from individuals of diverse ancestry and provide insights into the biological mechanisms regulating blood lipids to guide future genetic, biological and therapeutic research.
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Epicardial calcineurin-NFAT signals through Smad2 to direct coronary smooth muscle cell and arterial wall development.
Cardiovasc. Res.
PUBLISHED: 08-14-2013
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Congenital coronary artery anomalies produce serious events that include syncope, arrhythmias, myocardial infarction, or sudden death. Studying the mechanism of coronary development will contribute to the understanding of the disease and help design new diagnostic or therapeutic strategies. Here, we characterized a new calcineurin-NFAT signalling which specifically functions in the epicardium to regulate the development of smooth muscle wall of the coronary arteries.
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Mendelian randomization studies do not support a causal role for reduced circulating adiponectin levels in insulin resistance and type 2 diabetes.
Diabetes
PUBLISHED: 07-08-2013
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Adiponectin is strongly inversely associated with insulin resistance and type 2 diabetes, but its causal role remains controversial. We used a Mendelian randomization approach to test the hypothesis that adiponectin causally influences insulin resistance and type 2 diabetes. We used genetic variants at the ADIPOQ gene as instruments to calculate a regression slope between adiponectin levels and metabolic traits (up to 31,000 individuals) and a combination of instrumental variables and summary statistics-based genetic risk scores to test the associations with gold-standard measures of insulin sensitivity (2,969 individuals) and type 2 diabetes (15,960 case subjects and 64,731 control subjects). In conventional regression analyses, a 1-SD decrease in adiponectin levels was correlated with a 0.31-SD (95% CI 0.26-0.35) increase in fasting insulin, a 0.34-SD (0.30-0.38) decrease in insulin sensitivity, and a type 2 diabetes odds ratio (OR) of 1.75 (1.47-2.13). The instrumental variable analysis revealed no evidence of a causal association between genetically lower circulating adiponectin and higher fasting insulin (0.02 SD; 95% CI -0.07 to 0.11; N = 29,771), nominal evidence of a causal relationship with lower insulin sensitivity (-0.20 SD; 95% CI -0.38 to -0.02; N = 1,860), and no evidence of a relationship with type 2 diabetes (OR 0.94; 95% CI 0.75-1.19; N = 2,777 case subjects and 13,011 control subjects). Using the ADIPOQ summary statistics genetic risk scores, we found no evidence of an association between adiponectin-lowering alleles and insulin sensitivity (effect per weighted adiponectin-lowering allele: -0.03 SD; 95% CI -0.07 to 0.01; N = 2,969) or type 2 diabetes (OR per weighted adiponectin-lowering allele: 0.99; 95% CI 0.95-1.04; 15,960 case subjects vs. 64,731 control subjects). These results do not provide any consistent evidence that interventions aimed at increasing adiponectin levels will improve insulin sensitivity or risk of type 2 diabetes.
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Disease-related growth factor and embryonic signaling pathways modulate an enhancer of TCF21 expression at the 6q23.2 coronary heart disease locus.
PLoS Genet.
PUBLISHED: 07-01-2013
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Coronary heart disease (CHD) is the leading cause of mortality in both developed and developing countries worldwide. Genome-wide association studies (GWAS) have now identified 46 independent susceptibility loci for CHD, however, the biological and disease-relevant mechanisms for these associations remain elusive. The large-scale meta-analysis of GWAS recently identified in Caucasians a CHD-associated locus at chromosome 6q23.2, a region containing the transcription factor TCF21 gene. TCF21 (Capsulin/Pod1/Epicardin) is a member of the basic-helix-loop-helix (bHLH) transcription factor family, and regulates cell fate decisions and differentiation in the developing coronary vasculature. Herein, we characterize a cis-regulatory mechanism by which the lead polymorphism rs12190287 disrupts an atypical activator protein 1 (AP-1) element, as demonstrated by allele-specific transcriptional regulation, transcription factor binding, and chromatin organization, leading to altered TCF21 expression. Further, this element is shown to mediate signaling through platelet-derived growth factor receptor beta (PDGFR-?) and Wilms tumor 1 (WT1) pathways. A second disease allele identified in East Asians also appears to disrupt an AP-1-like element. Thus, both disease-related growth factor and embryonic signaling pathways may regulate CHD risk through two independent alleles at TCF21.
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Pancreatitis activates pancreatic apelin-APJ axis in mice.
Am. J. Physiol. Gastrointest. Liver Physiol.
PUBLISHED: 05-16-2013
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Pancreatitis is classified into acute pancreatitis (AP) and chronic pancreatitis (CP). Apelin, a small regulatory peptide, is the endogenous ligand for the APJ receptor. Apelin and APJ are expressed in the pancreas. The aims of this study were to examine whether apelin influences the inflammatory and fibrosis responses to pancreatitis in mice and to identify mechanisms behind apelins activities. Supramaximal cerulein induction of AP or CP caused significant (P < 0.05) elevations in pancreatic apelin and APJ expression. Levels declined during the recovery phases. In apelin gene-knockout mice with pancreatitis, pancreatic neutrophil invasion and myeloperoxidase activity were enhanced significantly, and apelin treatment suppressed both. Apelin exposure reduced CP-induced elevations of extracellular matrix-associated proteins. Apelin inhibited PDGF-simulated connective tissue growth factor production and proliferation of pancreatic stellate cells (PSCs). Serum granulocyte colony-stimulating factor and keratinocyte cytokine levels were higher in apelin gene-knockout than wild-type mice with pancreatitis. Apelin reduced AP- and CP-induced elevations in pancreatic NF-?B activation. Together, these findings imply that the pancreatic apelin-APJ system functions to curb the inflammatory and fibrosis responses during pancreatitis. Furthermore, findings suggest that apelin reduces inflammation and fibrosis by reducing neutrophil recruitment and PSC activity. Inhibition of neutrophil invasion may be mediated by reduced keratinocyte cytokine and granulocyte colony-stimulating factor secretion. Apelin-induced reductions in PSC proliferation and connective tissue growth factor production are putative mechanisms underlying apelins inhibition of extracellular matrix production. The apelin-associated changes in NF-?B binding may be linked to apelins regulation of pancreatic inflammatory and fibrosis responses during pancreatitis.
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Apelin-APJ signaling is a critical regulator of endothelial MEF2 activation in cardiovascular development.
Circ. Res.
PUBLISHED: 04-19-2013
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The peptide ligand apelin and its receptor APJ constitute a signaling pathway with numerous effects on the cardiovascular system, including cardiovascular development in model organisms such as xenopus and zebrafish.
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Increased bone mass in mice lacking the adipokine apelin.
Endocrinology
PUBLISHED: 04-12-2013
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Adipose tissue plays an important role in skeletal homeostasis, and there is interest in identifying adipokines that influence bone mass. One such adipokine may be apelin, a ligand for the Gi-G protein-coupled receptor APJ, which has been reported to enhance mitogenesis and suppress apoptosis in MC3T3-E1 cells and primary human osteoblasts (OBs). However, it is unclear whether apelin plays a physiological role in regulating skeletal homeostasis in vivo. In this study, we compared the skeletal phenotypes of apelin knockout (APKO) and wild-type mice and investigated the direct effects of apelin on bone cells in vitro. The increased fractional cancellous bone volume at the distal femur was observed in APKO mice of both genders at 12 weeks of age and persisted until the age of 20. Cortical bone perimeter at the femoral midshaft was significantly increased in males and females at both time points. Dynamic histomorphometry revealed that APKO mice had increased rates of bone formation and mineral apposition, with evidences of accelerated OB proliferation and differentiation, without significant alteration in osteoclast activity. An in vitro study showed that apelin increased proliferation of primary mouse OBs as well as suppressed apoptosis in a dose-dependent manner with the maximum effect at 5nM. However, it had no effect on the formation of mineralized nodules. We did not observed significantly altered in osteoclast parameters in vitro. Taken together, the increased bone mass in mice lacking apelin suggested complex direct and paracrine/endocrine effects of apelin on bone, possibly via modulating insulin sensitivity. These results indicate that apelin functions as a physiologically significant antianabolic factor in bone in vivo.
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Identification of heart rate-associated loci and their effects on cardiac conduction and rhythm disorders.
Marcel den Hoed, Mark Eijgelsheim, Tonu Esko, Bianca J J M Brundel, David S Peal, David M Evans, Ilja M Nolte, Ayellet V Segrè, Hilma Holm, Robert E Handsaker, Harm-Jan Westra, Toby Johnson, Aaron Isaacs, Jian Yang, Alicia Lundby, Jing Hua Zhao, Young Jin Kim, Min Jin Go, Peter Almgren, Murielle Bochud, Gabrielle Boucher, Marilyn C Cornelis, Daniel Gudbjartsson, David Hadley, Pim van der Harst, Caroline Hayward, Martin den Heijer, Wilmar Igl, Anne U Jackson, Zoltan Kutalik, Jian'an Luan, John P Kemp, Kati Kristiansson, Claes Ladenvall, Mattias Lorentzon, May E Montasser, Omer T Njajou, Paul F O'Reilly, Sandosh Padmanabhan, Beate St Pourcain, Tuomo Rankinen, Perttu Salo, Toshiko Tanaka, Nicholas J Timpson, Veronique Vitart, Lindsay Waite, William Wheeler, Weihua Zhang, Harmen H M Draisma, Mary F Feitosa, Kathleen F Kerr, Penelope A Lind, Evelin Mihailov, N Charlotte Onland-Moret, Ci Song, Michael N Weedon, Weijia Xie, Loïc Yengo, Devin Absher, Christine M Albert, Alvaro Alonso, Dan E Arking, Paul I W de Bakker, Beverley Balkau, Cristina Barlassina, Paola Benaglio, Joshua C Bis, Nabila Bouatia-Naji, Søren Brage, Stephen J Chanock, Peter S Chines, Mina Chung, Dawood Darbar, Christian Dina, Marcus Dörr, Paul Elliott, Stephan B Felix, Krista Fischer, Christian Fuchsberger, Eco J C de Geus, Philippe Goyette, Vilmundur Gudnason, Tamara B Harris, Anna-Liisa Hartikainen, Aki S Havulinna, Susan R Heckbert, Andrew A Hicks, Albert Hofman, Suzanne Holewijn, Femke Hoogstra-Berends, Jouke-Jan Hottenga, Majken K Jensen, Asa Johansson, Juhani Junttila, Stefan Kääb, Bart Kanon, Shamika Ketkar, Kay-Tee Khaw, Joshua W Knowles, Angrad S Kooner, Jan A Kors, Meena Kumari, Lili Milani, Päivi Laiho, Edward G Lakatta, Claudia Langenberg, Maarten Leusink, Yongmei Liu, Robert N Luben, Kathryn L Lunetta, Stacey N Lynch, Marcello R P Markus, Pedro Marques-Vidal, Irene Mateo Leach, Wendy L McArdle, Steven A McCarroll, Sarah E Medland, Kathryn A Miller, Grant W Montgomery, Alanna C Morrison, Martina Müller-Nurasyid, Pau Navarro, Mari Nelis, Jeffrey R O'Connell, Christopher J O'Donnell, Ken K Ong, Anne B Newman, Annette Peters, Ozren Polašek, Anneli Pouta, Peter P Pramstaller, Bruce M Psaty, Dabeeru C Rao, Susan M Ring, Elizabeth J Rossin, Diana Rudan, Serena Sanna, Robert A Scott, Jaban S Sehmi, Stephen Sharp, Jordan T Shin, Andrew B Singleton, Albert V Smith, Nicole Soranzo, Tim D Spector, Chip Stewart, Heather M Stringham, Kirill V Tarasov, André G Uitterlinden, Liesbeth Vandenput, Shih-Jen Hwang, John B Whitfield, Cisca Wijmenga, Sarah H Wild, Gonneke Willemsen, James F Wilson, Jacqueline C M Witteman, Andrew Wong, Quenna Wong, Yalda Jamshidi, Paavo Zitting, Jolanda M A Boer, Dorret I Boomsma, Ingrid B Borecki, Cornelia M van Duijn, Ulf Ekelund, Nita G Forouhi, Philippe Froguel, Aroon Hingorani, Erik Ingelsson, Mika Kivimäki, Richard A Kronmal, Diana Kuh, Lars Lind, Nicholas G Martin, Ben A Oostra, Nancy L Pedersen, Thomas Quertermous, Jerome I Rotter, Yvonne T van der Schouw, W M Monique Verschuren, Mark Walker, Demetrius Albanes, David O Arnar, Themistocles L Assimes, Stefania Bandinelli, Michael Boehnke, Rudolf A de Boer, Claude Bouchard, W L Mark Caulfield, John C Chambers, Gary Curhan, Daniele Cusi, Johan Eriksson, Luigi Ferrucci, Wiek H van Gilst, Nicola Glorioso, Jacqueline de Graaf, Leif Groop, Ulf Gyllensten, Wen-Chi Hsueh, Frank B Hu, Heikki V Huikuri, David J Hunter, Carlos Iribarren, Bo Isomaa, Marjo-Riitta Järvelin, Antti Jula, Mika Kähönen, Lambertus A Kiemeney, Melanie M van der Klauw, Jaspal S Kooner, Peter Kraft, Licia Iacoviello, Terho Lehtimäki, Marja-Liisa L Lokki, Braxton D Mitchell, Gerjan Navis, Markku S Nieminen, Claes Ohlsson, Neil R Poulter, Lu Qi, Olli T Raitakari, Eric B Rimm, John D Rioux, Federica Rizzi, Igor Rudan, Veikko Salomaa, Peter S Sever, Denis C Shields, Alan R Shuldiner, Juha Sinisalo, Alice V Stanton, Ronald P Stolk, David P Strachan, Jean-Claude Tardif, Unnur Thorsteinsdottir, Jaako Tuomilehto, Dirk J van Veldhuisen, Jarmo Virtamo, Jorma Viikari, Peter Vollenweider, Gérard Waeber, Elisabeth Widén, Yoon Shin Cho, Jesper V Olsen, Peter M Visscher, Cristen Willer, Lude Franke, , Jeanette Erdmann, John R Thompson, Arne Pfeufer, Nona Sotoodehnia, Christopher Newton-Cheh, Patrick T Ellinor, Bruno H Ch Stricker, Andres Metspalu, Markus Perola, Jacques S Beckmann, George Davey Smith, Kari Stefansson, Nicholas J Wareham, Patricia B Munroe, Ody C M Sibon, David J Milan, Harold Snieder, Nilesh J Samani, Ruth J F Loos.
Nat. Genet.
PUBLISHED: 03-21-2013
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Elevated resting heart rate is associated with greater risk of cardiovascular disease and mortality. In a 2-stage meta-analysis of genome-wide association studies in up to 181,171 individuals, we identified 14 new loci associated with heart rate and confirmed associations with all 7 previously established loci. Experimental downregulation of gene expression in Drosophila melanogaster and Danio rerio identified 20 genes at 11 loci that are relevant for heart rate regulation and highlight a role for genes involved in signal transmission, embryonic cardiac development and the pathophysiology of dilated cardiomyopathy, congenital heart failure and/or sudden cardiac death. In addition, genetic susceptibility to increased heart rate is associated with altered cardiac conduction and reduced risk of sick sinus syndrome, and both heart rate-increasing and heart rate-decreasing variants associate with risk of atrial fibrillation. Our findings provide fresh insights into the mechanisms regulating heart rate and identify new therapeutic targets.
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Trans-ethnic fine mapping identifies a novel independent locus at the 3 end of CDKAL1 and novel variants of several susceptibility loci for type 2 diabetes in a Han Chinese population.
Diabetologia
PUBLISHED: 02-27-2013
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Candidate gene and genome-wide association studies have identified ?60 susceptibility loci for type 2 diabetes. A majority of these loci have been discovered and tested only in European populations. The aim of this study was to assess the presence and extent of trans-ethnic effects of these loci in an East Asian population.
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Common variants associated with plasma triglycerides and risk for coronary artery disease.
Ron Do, Cristen J Willer, Ellen M Schmidt, Sebanti Sengupta, Chi Gao, Gina M Peloso, Stefan Gustafsson, Stavroula Kanoni, Andrea Ganna, Jin Chen, Martin L Buchkovich, Samia Mora, Jacques S Beckmann, Jennifer L Bragg-Gresham, Hsing-Yi Chang, Ayse Demirkan, Heleen M den Hertog, Louise A Donnelly, Georg B Ehret, Tonu Esko, Mary F Feitosa, Teresa Ferreira, Krista Fischer, Pierre Fontanillas, Ross M Fraser, Daniel F Freitag, Deepti Gurdasani, Kauko Heikkilä, Elina Hyppönen, Aaron Isaacs, Anne U Jackson, Asa Johansson, Toby Johnson, Marika Kaakinen, Johannes Kettunen, Marcus E Kleber, Xiaohui Li, Jian'an Luan, Leo-Pekka Lyytikäinen, Patrik K E Magnusson, Massimo Mangino, Evelin Mihailov, May E Montasser, Martina Müller-Nurasyid, Ilja M Nolte, Jeffrey R O'Connell, Cameron D Palmer, Markus Perola, Ann-Kristin Petersen, Serena Sanna, Richa Saxena, Susan K Service, Sonia Shah, Dmitry Shungin, Carlo Sidore, Ci Song, Rona J Strawbridge, Ida Surakka, Toshiko Tanaka, Tanya M Teslovich, Gudmar Thorleifsson, Evita G van den Herik, Benjamin F Voight, Kelly A Volcik, Lindsay L Waite, Andrew Wong, Ying Wu, Weihua Zhang, Devin Absher, Gershim Asiki, Inês Barroso, Latonya F Been, Jennifer L Bolton, Lori L Bonnycastle, Paolo Brambilla, Mary S Burnett, Giancarlo Cesana, Maria Dimitriou, Alex S F Doney, Angela Döring, Paul Elliott, Stephen E Epstein, Gudmundur Ingi Eyjolfsson, Bruna Gigante, Mark O Goodarzi, Harald Grallert, Martha L Gravito, Christopher J Groves, Göran Hallmans, Anna-Liisa Hartikainen, Caroline Hayward, Dena Hernandez, Andrew A Hicks, Hilma Holm, Yi-Jen Hung, Thomas Illig, Michelle R Jones, Pontiano Kaleebu, John J P Kastelein, Kay-Tee Khaw, Eric Kim, Norman Klopp, Pirjo Komulainen, Meena Kumari, Claudia Langenberg, Terho Lehtimäki, Shih-Yi Lin, Jaana Lindström, Ruth J F Loos, François Mach, Wendy L McArdle, Christa Meisinger, Braxton D Mitchell, Gabrielle Müller, Ramaiah Nagaraja, Narisu Narisu, Tuomo V M Nieminen, Rebecca N Nsubuga, Isleifur Olafsson, Ken K Ong, Aarno Palotie, Theodore Papamarkou, Cristina Pomilla, Anneli Pouta, Daniel J Rader, Muredach P Reilly, Paul M Ridker, Fernando Rivadeneira, Igor Rudan, Aimo Ruokonen, Nilesh Samani, Hubert Scharnagl, Janet Seeley, Kaisa Silander, Alena Stančáková, Kathleen Stirrups, Amy J Swift, Laurence Tiret, André G Uitterlinden, L Joost van Pelt, Sailaja Vedantam, Nicholas Wainwright, Cisca Wijmenga, Sarah H Wild, Gonneke Willemsen, Tom Wilsgaard, James F Wilson, Elizabeth H Young, Jing Hua Zhao, Linda S Adair, Dominique Arveiler, Themistocles L Assimes, Stefania Bandinelli, Franklyn Bennett, Murielle Bochud, Bernhard O Boehm, Dorret I Boomsma, Ingrid B Borecki, Stefan R Bornstein, Pascal Bovet, Michel Burnier, Harry Campbell, Aravinda Chakravarti, John C Chambers, Yii-Der Ida Chen, Francis S Collins, Richard S Cooper, John Danesh, George Dedoussis, Ulf de Faire, Alan B Feranil, Jean Ferrières, Luigi Ferrucci, Nelson B Freimer, Christian Gieger, Leif C Groop, Vilmundur Gudnason, Ulf Gyllensten, Anders Hamsten, Tamara B Harris, Aroon Hingorani, Joel N Hirschhorn, Albert Hofman, G Kees Hovingh, Chao Agnes Hsiung, Steve E Humphries, Steven C Hunt, Kristian Hveem, Carlos Iribarren, Marjo-Riitta Järvelin, Antti Jula, Mika Kähönen, Jaakko Kaprio, Antero Kesäniemi, Mika Kivimäki, Jaspal S Kooner, Peter J Koudstaal, Ronald M Krauss, Diana Kuh, Johanna Kuusisto, Kirsten O Kyvik, Markku Laakso, Timo A Lakka, Lars Lind, Cecilia M Lindgren, Nicholas G Martin, Winfried März, Mark I McCarthy, Colin A McKenzie, Pierre Meneton, Andres Metspalu, Leena Moilanen, Andrew D Morris, Patricia B Munroe, Inger Njølstad, Nancy L Pedersen, Chris Power, Peter P Pramstaller, Jackie F Price, Bruce M Psaty, Thomas Quertermous, Rainer Rauramaa, Danish Saleheen, Veikko Salomaa, Dharambir K Sanghera, Jouko Saramies, Peter E H Schwarz, Wayne H-H Sheu, Alan R Shuldiner, Agneta Siegbahn, Tim D Spector, Kari Stefansson, David P Strachan, Bamidele O Tayo, Elena Tremoli, Jaakko Tuomilehto, Matti Uusitupa, Cornelia M van Duijn, Peter Vollenweider, Lars Wallentin, Nicholas J Wareham, John B Whitfield, Bruce H R Wolffenbuttel, David Altshuler, José M Ordovás, Eric Boerwinkle, Colin N A Palmer, Unnur Thorsteinsdottir, Daniel I Chasman, Jerome I Rotter, Paul W Franks, Samuli Ripatti, L Adrienne Cupples, Manjinder S Sandhu, Stephen S Rich, Michael Boehnke, Panos Deloukas, Karen L Mohlke, Erik Ingelsson, Gonçalo R Abecasis, Mark J Daly, Benjamin M Neale, Sekar Kathiresan.
Nat. Genet.
PUBLISHED: 02-20-2013
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Triglycerides are transported in plasma by specific triglyceride-rich lipoproteins; in epidemiological studies, increased triglyceride levels correlate with higher risk for coronary artery disease (CAD). However, it is unclear whether this association reflects causal processes. We used 185 common variants recently mapped for plasma lipids (P < 5 × 10(-8) for each) to examine the role of triglycerides in risk for CAD. First, we highlight loci associated with both low-density lipoprotein cholesterol (LDL-C) and triglyceride levels, and we show that the direction and magnitude of the associations with both traits are factors in determining CAD risk. Second, we consider loci with only a strong association with triglycerides and show that these loci are also associated with CAD. Finally, in a model accounting for effects on LDL-C and/or high-density lipoprotein cholesterol (HDL-C) levels, the strength of a polymorphisms effect on triglyceride levels is correlated with the magnitude of its effect on CAD risk. These results suggest that triglyceride-rich lipoproteins causally influence risk for CAD.
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Genetic variants associated with glycine metabolism and their role in insulin sensitivity and type 2 diabetes.
Diabetes
PUBLISHED: 02-01-2013
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Circulating metabolites associated with insulin sensitivity may represent useful biomarkers, but their causal role in insulin sensitivity and diabetes is less certain. We previously identified novel metabolites correlated with insulin sensitivity measured by the hyperinsulinemic-euglycemic clamp. The top-ranking metabolites were in the glutathione and glycine biosynthesis pathways. We aimed to identify common genetic variants associated with metabolites in these pathways and test their role in insulin sensitivity and type 2 diabetes. With 1,004 nondiabetic individuals from the RISC study, we performed a genome-wide association study (GWAS) of 14 insulin sensitivity-related metabolites and one metabolite ratio. We replicated our results in the Botnia study (n = 342). We assessed the association of these variants with diabetes-related traits in GWAS meta-analyses (GENESIS [including RISC, EUGENE2, and Stanford], MAGIC, and DIAGRAM). We identified four associations with three metabolites-glycine (rs715 at CPS1), serine (rs478093 at PHGDH), and betaine (rs499368 at SLC6A12; rs17823642 at BHMT)-and one association signal with glycine-to-serine ratio (rs1107366 at ALDH1L1). There was no robust evidence for association between these variants and insulin resistance or diabetes. Genetic variants associated with genes in the glycine biosynthesis pathways do not provide consistent evidence for a role of glycine in diabetes-related traits.
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Clinical utility of a novel coronary heart disease risk-assessment test to further classify intermediate-risk patients.
Clin Cardiol
PUBLISHED: 01-19-2013
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Current coronary heart disease (CHD) risk assessments inadequately assess intermediate-risk patients, leaving many undertreated and vulnerable to heart attacks. A novel CHD risk-assessment (CHDRA) tool was developed for intermediate-risk stratification using biomarkers and established risk factors to significantly improve CHD risk discrimination.
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Trans-ethnic fine-mapping of lipid loci identifies population-specific signals and allelic heterogeneity that increases the trait variance explained.
PLoS Genet.
PUBLISHED: 01-19-2013
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Genome-wide association studies (GWAS) have identified ~100 loci associated with blood lipid levels, but much of the trait heritability remains unexplained, and at most loci the identities of the trait-influencing variants remain unknown. We conducted a trans-ethnic fine-mapping study at 18, 22, and 18 GWAS loci on the Metabochip for their association with triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), respectively, in individuals of African American (n = 6,832), East Asian (n = 9,449), and European (n = 10,829) ancestry. We aimed to identify the variants with strongest association at each locus, identify additional and population-specific signals, refine association signals, and assess the relative significance of previously described functional variants. Among the 58 loci, 33 exhibited evidence of association at P<1 × 10(-4) in at least one ancestry group. Sequential conditional analyses revealed that ten, nine, and four loci in African Americans, Europeans, and East Asians, respectively, exhibited two or more signals. At these loci, accounting for all signals led to a 1.3- to 1.8-fold increase in the explained phenotypic variance compared to the strongest signals. Distinct signals across ancestry groups were identified at PCSK9 and APOA5. Trans-ethnic analyses narrowed the signals to smaller sets of variants at GCKR, PPP1R3B, ABO, LCAT, and ABCA1. Of 27 variants reported previously to have functional effects, 74% exhibited the strongest association at the respective signal. In conclusion, trans-ethnic high-density genotyping and analysis confirm the presence of allelic heterogeneity, allow the identification of population-specific variants, and limit the number of candidate SNPs for functional studies.
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Endothelin Type A Receptor Genotype is a Determinant of Quantitative Traits of Metabolic Syndrome in Asian Hypertensive Families: A SAPPHIRe Study.
Front Endocrinol (Lausanne)
PUBLISHED: 01-01-2013
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Co-heritability of hypertension and insulin resistance (IR) within families not only implies genetic susceptibility may be responsible for these complex traits but also suggests a rational that biological candidate genes for hypertension may serve as markers for features of the metabolic syndrome (MetS). Thus we determined whether the T323C polymorphism (rs5333) of endothelin type A (ETA) receptor, a predominant receptor evoking potent vasoconstrictive action of endothelin-1, contributes to susceptibility to IR-associated hypertension in 1694 subjects of Chinese and Japanese origins. Blood pressures (BPs) and biochemistries were measured. Fasting insulin level, insulin-resistance homeostasis model assessment (HOMAIR) score, and area under curve of insulin concentration (AUCINS) were selected for assessing insulin sensitivity. Genotypes were obtained by methods of polymerase chain reaction-restriction fragment length polymorphism. Foremost findings were that minor allele frequency of the T323C polymorphism was noticeable lower in our overall Asian subjects compared to multi-national population reported in gene database; moreover both the genotypic and allelic frequencies of the polymorphism were significantly different between the two ethnic groups we studied. The genotype distributions at TT/TC/CC were 65, 31, 4% in Chinese and 51, 41, 8% in Japanese, respectively (p?
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A TNF variant that associates with susceptibility to musculoskeletal disease modulates thyroid hormone receptor binding to control promoter activation.
PLoS ONE
PUBLISHED: 01-01-2013
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Tumor necrosis factor (TNF) is a powerful pro-inflammatory cytokine and immuno-regulatory molecule, and modulates susceptibility to musculoskeletal diseases. Several meta-analyses and replicated association studies have implicated the minor A variant within the TNF promoter single nucleotide polymorphism (SNP) rs361525 (-238A/G) as a risk allele in joint related disorders, including psoriatic and juvenile idiopathic arthritis, and osteolysis after joint arthroplasty. Here we characterized the effect of this variant on TNF promoter function. A transcriptional reporter, encoding the -238A variant of the TNF promoter, resulted in 2.2 to 2.8 times greater transcriptional activation versus the G variant in murine macrophages when stimulated with pro-inflammatory stimuli. Bioinformatic analysis predicted a putative binding site for thyroid hormone receptor (TR) for the -238A but not the -238G allele. Overexpression of TR-? induced promoter expression 1.8-fold in the presence of the A allele only. TR-? expression both potentiated and sensitized the -238A response to LPS or a titanium particulate stimulus, whilst siRNA knockdown of either THRA or THRB impaired transcriptional activation for the -238A variant only. This effect was independent of receptor-ligand binding of triiodothyronine. Immunohistochemical analysis of osteolysis interface membranes from patients undergoing revision surgery confirmed expression of TR-? within osteoclast nuclei at the resorption surface. The A allele at rs361525 confers increased transcriptional activation of the TNF promoter and influences susceptibility to several arthritic conditions. This effect is modulated, at least in part, by binding of TR, which both sensitizes and potentiates transcriptional activation of the A variant independent of its endogenous ligand.
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The angiogenic factor Del1 prevents apoptosis of endothelial cells through integrin binding.
Surgery
PUBLISHED: 07-06-2011
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Del1 is a secreted protein that is expressed in the endothelium during development and can stimulate angiogenesis through integrin binding and signaling. We were interested in the specific effects of del1 on endothelial cell biology to gain insight into its biologic role during angiogenesis.
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Racial variation in lipoprotein-associated phospholipase A? in older adults.
BMC Cardiovasc Disord
PUBLISHED: 06-29-2011
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Lipoprotein-associated phospholipase A? (Lp-PLA?) is a predictor of cardiovascular events that has been shown to vary with race. The objective of this study was to examine factors associated with this racial variation.
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Cardiac pressure overload hypertrophy is differentially regulated by ?-adrenergic receptor subtypes.
Am. J. Physiol. Heart Circ. Physiol.
PUBLISHED: 06-24-2011
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In isolated myocytes, hypertrophy induced by norepinephrine is mediated via ?(1)-adrenergic receptors (ARs) and not ?-ARs. However, mice with deletions of both major cardiac ?(1)-ARs still develop hypertrophy in response to pressure overload. Our purpose was to better define the role of ?-AR subtypes in regulating cardiac hypertrophy in vivo, important given the widespread clinical use of ?-AR antagonists and the likelihood that patients treated with these agents could develop conditions of further afterload stress. Mice with deletions of ?(1), ?(2), or both ?(1)- and ?(2)-ARs were subjected to transverse aortic constriction (TAC). After 3 wk, ?(1)(-/-) showed a 21% increase in heart to body weight vs. sham controls, similar to wild type, whereas ?(2)(-/-) developed exaggerated (49% increase) hypertrophy. Only when both ?-ARs were ablated (?(1)?(2)(-/-)) was hypertrophy totally abolished. Cardiac function was preserved in all genotypes. Several known inhibitors of cardiac hypertrophy (FK506 binding protein 5, thioredoxin interacting protein, and S100A9) were upregulated in ?(1)?(2)(-/-) compared with the other genotypes, whereas transforming growth factor-?(2), a positive mediator of hypertrophy was upregulated in all genotypes except the ?(1)?(2)(-/-). In contrast to recent reports suggesting that angiogenesis plays a critical role in regulating cardiac hypertrophy-induced heart failure, we found no evidence that angiogenesis or its regulators (VEGF, Hif1?, and p53) play a role in compensated cardiac hypertrophy. Pressure overload hypertrophy in vivo is dependent on a coordination of signaling through both ?(1)- and ?(2)-ARs, mediated through several key cardiac remodeling pathways. Angiogenesis is not a prerequisite for compensated cardiac hypertrophy.
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In vivo bioluminescence imaging of inducible nitric oxide synthase gene expression in vascular inflammation.
Mol Imaging Biol
PUBLISHED: 06-15-2011
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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.
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A bivariate genome-wide approach to metabolic syndrome: STAMPEED consortium.
Diabetes
PUBLISHED: 03-08-2011
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OBJECTIVE The metabolic syndrome (MetS) is defined as concomitant disorders of lipid and glucose metabolism, central obesity, and high blood pressure, with an increased risk of type 2 diabetes and cardiovascular disease. This study tests whether common genetic variants with pleiotropic effects account for some of the correlated architecture among five metabolic phenotypes that define MetS. RESEARCH DESIGN AND METHODS Seven studies of the STAMPEED consortium, comprising 22,161 participants of European ancestry, underwent genome-wide association analyses of metabolic traits using a panel of ?2.5 million imputed single nucleotide polymorphisms (SNPs). Phenotypes were defined by the National Cholesterol Education Program (NCEP) criteria for MetS in pairwise combinations. Individuals exceeding the NCEP thresholds for both traits of a pair were considered affected. RESULTS Twenty-nine common variants were associated with MetS or a pair of traits. Variants in the genes LPL, CETP, APOA5 (and its cluster), GCKR (and its cluster), LIPC, TRIB1, LOC100128354/MTNR1B, ABCB11, and LOC100129150 were further tested for their association with individual qualitative and quantitative traits. None of the 16 top SNPs (one per gene) associated simultaneously with more than two individual traits. Of them 11 variants showed nominal associations with MetS per se. The effects of 16 top SNPs on the quantitative traits were relatively small, together explaining from ?9% of the variance in triglycerides, 5.8% of high-density lipoprotein cholesterol, 3.6% of fasting glucose, and 1.4% of systolic blood pressure. CONCLUSIONS Qualitative and quantitative pleiotropic tests on pairs of traits indicate that a small portion of the covariation in these traits can be explained by the reported common genetic variants.
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MicroRNA-26a is a novel regulator of vascular smooth muscle cell function.
J. Cell. Physiol.
PUBLISHED: 03-03-2011
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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-?-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?
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In vivo molecular MRI of cell survival and teratoma formation following embryonic stem cell transplantation into the injured murine myocardium.
Magn Reson Med
PUBLISHED: 02-24-2011
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Embryonic stem cells (ESCs) have shown the potential to restore cardiac function after myocardial injury. Superparamagnetic iron oxide nanoparticles (SPIO) have been widely employed to label ESCs for cellular MRI. However, nonspecific intracellular accumulation of SPIO limits long-term in vivo assessment of the transplanted cells. To overcome this limitation, a novel reporter gene (RG) has been developed to express antigens on the ESC surface. By employing SPIO-conjugated monoclonal antibody against these antigens (SPIO-MAb), the viability of transplanted ESCs can be detected in vivo. This study aims to develop a new molecular MRI method to assess in vivo ESC viability, proliferation, and teratoma formation. The RG is designed to express 2 antigens (hemagglutinin A and myc) and luciferase on the ESC surface. The two antigens serve as the molecular targets for SPIO-MAb. The human and mouse ESCs were transduced with the RG (ESC-RGs) and transplanted into the peri-infarct area using the murine myocardial injury model. In vivo MRI was performed following serial intravenous administration of SPIO-MAb. Significant hypointense signal was generated from the viable and proliferating ESCs and subsequent teratoma. This novel molecular MRI technique enabled in vivo detection of early ESC-derived teratoma formation in the injured murine myocardium.
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Large-scale association analysis identifies 13 new susceptibility loci for coronary artery disease.
Heribert Schunkert, Inke R König, Sekar Kathiresan, Muredach P Reilly, Themistocles L Assimes, Hilma Holm, Michael Preuss, Alexandre F R Stewart, Maja Barbalic, Christian Gieger, Devin Absher, Zouhair Aherrahrou, Hooman Allayee, David Altshuler, Sonia S Anand, Karl Andersen, Jeffrey L Anderson, Diego Ardissino, Stephen G Ball, Anthony J Balmforth, Timothy A Barnes, Diane M Becker, Lewis C Becker, Klaus Berger, Joshua C Bis, S Matthijs Boekholdt, Eric Boerwinkle, Peter S Braund, Morris J Brown, Mary Susan Burnett, Ian Buysschaert, , John F Carlquist, Li Chen, Sven Cichon, Veryan Codd, Robert W Davies, George Dedoussis, Abbas Dehghan, Serkalem Demissie, Joseph M Devaney, Patrick Diemert, Ron Do, Angela Doering, Sandra Eifert, Nour Eddine El Mokhtari, Stephen G Ellis, Roberto Elosua, James C Engert, Stephen E Epstein, Ulf de Faire, Marcus Fischer, Aaron R Folsom, Jennifer Freyer, Bruna Gigante, Domenico Girelli, Solveig Gretarsdottir, Vilmundur Gudnason, Jeffrey R Gulcher, Eran Halperin, Naomi Hammond, Stanley L Hazen, Albert Hofman, Benjamin D Horne, Thomas Illig, Carlos Iribarren, Gregory T Jones, J Wouter Jukema, Michael A Kaiser, Lee M Kaplan, John J P Kastelein, Kay-Tee Khaw, Joshua W Knowles, Genovefa Kolovou, Augustine Kong, Reijo Laaksonen, Diether Lambrechts, Karin Leander, Guillaume Lettre, Mingyao Li, Wolfgang Lieb, Christina Loley, Andrew J Lotery, Pier M Mannucci, Seraya Maouche, Nicola Martinelli, Pascal P McKeown, Christa Meisinger, Thomas Meitinger, Olle Melander, Pier Angelica Merlini, Vincent Mooser, Thomas Morgan, Thomas W Mühleisen, Joseph B Muhlestein, Thomas Münzel, Kiran Musunuru, Janja Nahrstaedt, Christopher P Nelson, Markus M Nöthen, Oliviero Olivieri, Riyaz S Patel, Chris C Patterson, Annette Peters, Flora Peyvandi, Liming Qu, Arshed A Quyyumi, Daniel J Rader, Loukianos S Rallidis, Catherine Rice, Frits R Rosendaal, Diana Rubin, Veikko Salomaa, M Lourdes Sampietro, Manj S Sandhu, Eric Schadt, Arne Schäfer, Arne Schillert, Stefan Schreiber, Jürgen Schrezenmeir, Stephen M Schwartz, David S Siscovick, Mohan Sivananthan, Suthesh Sivapalaratnam, Albert Smith, Tamara B Smith, Jaapjan D Snoep, Nicole Soranzo, John A Spertus, Klaus Stark, Kathy Stirrups, Monika Stoll, W H Wilson Tang, Stephanie Tennstedt, Gudmundur Thorgeirsson, Gudmar Thorleifsson, Maciej Tomaszewski, André G Uitterlinden, Andre M van Rij, Benjamin F Voight, Nick J Wareham, George A Wells, H-Erich Wichmann, Philipp S Wild, Christina Willenborg, Jaqueline C M Witteman, Benjamin J Wright, Shu Ye, Tanja Zeller, Andreas Ziegler, Francois Cambien, Alison H Goodall, L Adrienne Cupples, Thomas Quertermous, Winfried März, Christian Hengstenberg, Stefan Blankenberg, Willem H Ouwehand, Alistair S Hall, Panos Deloukas, John R Thompson, Kari Stefansson, Robert Roberts, Unnur Thorsteinsdottir, Christopher J O'Donnell, Ruth McPherson, Jeanette Erdmann, Nilesh J Samani.
Nat. Genet.
PUBLISHED: 02-10-2011
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We performed a meta-analysis of 14 genome-wide association studies of coronary artery disease (CAD) comprising 22,233 individuals with CAD (cases) and 64,762 controls of European descent followed by genotyping of top association signals in 56,682 additional individuals. This analysis identified 13 loci newly associated with CAD at P < 5 × 10?? and confirmed the association of 10 of 12 previously reported CAD loci. The 13 new loci showed risk allele frequencies ranging from 0.13 to 0.91 and were associated with a 6% to 17% increase in the risk of CAD per allele. Notably, only three of the new loci showed significant association with traditional CAD risk factors and the majority lie in gene regions not previously implicated in the pathogenesis of CAD. Finally, five of the new CAD risk loci appear to have pleiotropic effects, showing strong association with various other human diseases or traits.
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Disruption of the apelin-APJ system worsens hypoxia-induced pulmonary hypertension.
Arterioscler. Thromb. Vasc. Biol.
PUBLISHED: 01-13-2011
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The G-protein-coupled receptor APJ and its ligand apelin are highly expressed in the pulmonary vasculature, but their function in this vascular bed is unclear. We hypothesized that disruption of apelin signaling would lead to worsening of the vascular remodeling associated with pulmonary hypertension (PH).
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Apelin decreases lipolysis via G(q), G(i), and AMPK-Dependent Mechanisms.
Endocrinology
PUBLISHED: 11-03-2010
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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 apelins 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. Apelins 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.
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Design of the Coronary ARtery DIsease Genome-Wide Replication And Meta-Analysis (CARDIoGRAM) Study: A Genome-wide association meta-analysis involving more than 22 000 cases and 60 000 controls.
Circ Cardiovasc Genet
PUBLISHED: 10-05-2010
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Recent genome-wide association studies (GWAS) of myocardial infarction (MI) and other forms of coronary artery disease (CAD) have led to the discovery of at least 13 genetic loci. In addition to the effect size, power to detect associations is largely driven by sample size. Therefore, to maximize the chance of finding novel susceptibility loci for CAD and MI, the Coronary ARtery DIsease Genome-wide Replication And Meta-analysis (CARDIoGRAM) consortium was formed.
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Distribution of the number of false discoveries in large-scale family-based association testing with application to the association between PTPN1 and hypertension and obesity.
Hum. Genet.
PUBLISHED: 08-25-2010
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We present a model-free approach to the study of the number of false discoveries for large-scale simultaneous family-based association tests (FBATs) in which the set of discoveries is decided by applying a threshold to the test statistics. When the association between a set of markers in a candidate gene and a group of phenotypes is studied by a class of FBATs, we indicate that a joint null hypothesis distribution for these statistics can be obtained by the fundamental statistical method of conditioning on sufficient statistics for the null hypothesis. Based on the joint null distribution of these statistics, we can obtain the distribution of the number of false discoveries for the set of discoveries defined by a threshold; the size of this set is referred to as its tail count. Simulation studies are presented to demonstrate that the conditional, not the unconditional, distribution of the tail count is appropriate for the study of false discoveries. The usefulness of this approach is illustrated by re-examining the association between PTPN1 and a group of blood-pressure-related phenotypes reported by Olivier et al. (Hum Mol Genet 13:1885-1892, 2004); our results refine and reinforce this association.
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An "almost exhaustive" search-based sequential permutation method for detecting epistasis in disease association studies.
Genet. Epidemiol.
PUBLISHED: 06-29-2010
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Due to the complex nature of common diseases, their etiology is likely to involve "uncommon but strong" (UBS) interactive effects--i.e. allelic combinations that are each present in only a small fraction of the patients but associated with high disease risk. However, the identification of such effects using standard methods for testing association can be difficult. In this work, we introduce a method for testing interactions that is particularly powerful in detecting UBS effects. The method consists of two modules--one is a pattern counting algorithm designed for efficiently evaluating the risk significance of each marker combination, and the other is a sequential permutation scheme for multiple testing correction. We demonstrate the work of our method using a candidate gene data set for cardiovascular and coronary diseases with an injected UBS three-locus interaction. In addition, we investigate the power and false rejection properties of our method using data sets simulated from a joint dominance three-locus model that gives rise to UBS interactive effects. The results show that our method can be much more powerful than standard approaches such as trend test and multifactor dimensionality reduction for detecting UBS interactions.
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Chromatin remodeling pathways in smooth muscle cell differentiation, and evidence for an integral role for p300.
PLoS ONE
PUBLISHED: 06-23-2010
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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.
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Impact of combined deficiency of hepatic lipase and endothelial lipase on the metabolism of both high-density lipoproteins and apolipoprotein B-containing lipoproteins.
Circ. Res.
PUBLISHED: 06-17-2010
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Hepatic lipase (HL) and endothelial lipase (EL) are extracellular lipases that both hydrolyze triglycerides and phospholipids and display potentially overlapping or complementary roles in lipoprotein metabolism.
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Lack of association between the Trp719Arg polymorphism in kinesin-like protein-6 and coronary artery disease in 19 case-control studies.
Themistocles L Assimes, Hilma Holm, Sekar Kathiresan, Muredach P Reilly, Gudmar Thorleifsson, Benjamin F Voight, Jeanette Erdmann, Christina Willenborg, Dhananjay Vaidya, Changchun Xie, Chris C Patterson, Thomas M Morgan, Mary Susan Burnett, Mingyao Li, Mark A Hlatky, Joshua W Knowles, John R Thompson, Devin Absher, Carlos Iribarren, Alan Go, Stephen P Fortmann, Stephen Sidney, Neil Risch, Hua Tang, Richard M Myers, Klaus Berger, Monika Stoll, Svati H Shah, Gudmundur Thorgeirsson, Karl Andersen, Aki S Havulinna, J Enrique Herrera, Nauder Faraday, Yoonhee Kim, Brian G Kral, Rasika A Mathias, Ingo Ruczinski, Bhoom Suktitipat, Alexander F Wilson, Lisa R Yanek, Lewis C Becker, Patrick Linsel-Nitschke, Wolfgang Lieb, Inke R König, Christian Hengstenberg, Marcus Fischer, Klaus Stark, Wibke Reinhard, Janina Winogradow, Martina Grassl, Anika Grosshennig, Michael Preuss, Stefan Schreiber, H-Erich Wichmann, Christa Meisinger, Jean Yee, Yechiel Friedlander, Ron Do, James B Meigs, Gordon Williams, David M Nathan, Calum A MacRae, Liming Qu, Robert L Wilensky, William H Matthai, Atif N Qasim, Hakon Hakonarson, Augusto D Pichard, Kenneth M Kent, Lowell Satler, Joseph M Lindsay, Ron Waksman, Christopher W Knouff, Dawn M Waterworth, Max C Walker, Vincent E Mooser, Jaume Marrugat, Gavin Lucas, Isaac Subirana, Joan Sala, Rafael Ramos, Nicola Martinelli, Oliviero Olivieri, Elisabetta Trabetti, Giovanni Malerba, Pier Franco Pignatti, Candace Guiducci, Daniel Mirel, Melissa Parkin, Joel N Hirschhorn, Rosanna Asselta, Stefano Duga, Kiran Musunuru, Mark J Daly, Shaun Purcell, Sandra Eifert, Peter S Braund, Benjamin J Wright, Anthony J Balmforth, Stephen G Ball, , Willem H Ouwehand, Panos Deloukas, Michael Scholz, Francois Cambien, Andreas Huge, Thomas Scheffold, Veikko Salomaa, Domenico Girelli, Christopher B Granger, Leena Peltonen, Pascal P McKeown, David Altshuler, Olle Melander, Joseph M Devaney, Stephen E Epstein, Daniel J Rader, Roberto Elosua, James C Engert, Sonia S Anand, Alistair S Hall, Andreas Ziegler, Christopher J O'Donnell, John A Spertus, David Siscovick, Stephen M Schwartz, Diane Becker, Unnur Thorsteinsdottir, Kari Stefansson, Heribert Schunkert, Nilesh J Samani, Thomas Quertermous.
J. Am. Coll. Cardiol.
PUBLISHED: 06-14-2010
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We sought to replicate the association between the kinesin-like protein 6 (KIF6) Trp719Arg polymorphism (rs20455), and clinical coronary artery disease (CAD).
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Association analyses of 249,796 individuals reveal 18 new loci associated with body mass index.
Elizabeth K Speliotes, Cristen J Willer, Sonja I Berndt, Keri L Monda, Gudmar Thorleifsson, Anne U Jackson, Hana Lango Allen, Cecilia M Lindgren, Jian'an Luan, Reedik Mägi, Joshua C Randall, Sailaja Vedantam, Thomas W Winkler, Lu Qi, Tsegaselassie Workalemahu, Iris M Heid, Valgerdur Steinthorsdottir, Heather M Stringham, Michael N Weedon, Eleanor Wheeler, Andrew R Wood, Teresa Ferreira, Robert J Weyant, Ayellet V Segrè, Karol Estrada, Liming Liang, James Nemesh, Ju-Hyun Park, Stefan Gustafsson, Tuomas O Kilpeläinen, Jian Yang, Nabila Bouatia-Naji, Tonu Esko, Mary F Feitosa, Zoltan Kutalik, Massimo Mangino, Soumya Raychaudhuri, André Scherag, Albert Vernon Smith, Ryan Welch, Jing Hua Zhao, Katja K Aben, Devin M Absher, Najaf Amin, Anna L Dixon, Eva Fisher, Nicole L Glazer, Michael E Goddard, Nancy L Heard-Costa, Volker Hoesel, Jouke-Jan Hottenga, Asa Johansson, Toby Johnson, Shamika Ketkar, Claudia Lamina, Shengxu Li, Miriam F Moffatt, Richard H Myers, Narisu Narisu, John R B Perry, Marjolein J Peters, Michael Preuss, Samuli Ripatti, Fernando Rivadeneira, Camilla Sandholt, Laura J Scott, Nicholas J Timpson, Jonathan P Tyrer, Sophie van Wingerden, Richard M Watanabe, Charles C White, Fredrik Wiklund, Christina Barlassina, Daniel I Chasman, Matthew N Cooper, John-Olov Jansson, Robert W Lawrence, Niina Pellikka, Inga Prokopenko, Jianxin Shi, Elisabeth Thiering, Helene Alavere, Maria T S Alibrandi, Peter Almgren, Alice M Arnold, Thor Aspelund, Larry D Atwood, Beverley Balkau, Anthony J Balmforth, Amanda J Bennett, Yoav Ben-Shlomo, Richard N Bergman, Sven Bergmann, Heike Biebermann, Alexandra I F Blakemore, Tanja Boes, Lori L Bonnycastle, Stefan R Bornstein, Morris J Brown, Thomas A Buchanan, Fabio Busonero, Harry Campbell, Francesco P Cappuccio, Christine Cavalcanti-Proença, Yii-Der Ida Chen, Chih-Mei Chen, Peter S Chines, Robert Clarke, Lachlan Coin, John Connell, Ian N M Day, Martin den Heijer, Jubao Duan, Shah Ebrahim, Paul Elliott, Roberto Elosua, Gudny Eiriksdottir, Michael R Erdos, Johan G Eriksson, Maurizio F Facheris, Stephan B Felix, Pamela Fischer-Posovszky, Aaron R Folsom, Nele Friedrich, Nelson B Freimer, Mao Fu, Stefan Gaget, Pablo V Gejman, Eco J C Geus, Christian Gieger, Anette P Gjesing, Anuj Goel, Philippe Goyette, Harald Grallert, Jürgen Gräßler, Danielle M Greenawalt, Christopher J Groves, Vilmundur Gudnason, Candace Guiducci, Anna-Liisa Hartikainen, Neelam Hassanali, Alistair S Hall, Aki S Havulinna, Caroline Hayward, Andrew C Heath, Christian Hengstenberg, Andrew A Hicks, Anke Hinney, Albert Hofman, Georg Homuth, Jennie Hui, Wilmar Igl, Carlos Iribarren, Bo Isomaa, Kevin B Jacobs, Ivonne Jarick, Elizabeth Jewell, Ulrich John, Torben Jørgensen, Pekka Jousilahti, Antti Jula, Marika Kaakinen, Eero Kajantie, Lee M Kaplan, Sekar Kathiresan, Johannes Kettunen, Leena Kinnunen, Joshua W Knowles, Ivana Kolčić, Inke R König, Seppo Koskinen, Peter Kovacs, Johanna Kuusisto, Peter Kraft, Kirsti Kvaløy, Jaana Laitinen, Olivier Lantieri, Chiara Lanzani, Lenore J Launer, Cécile Lecoeur, Terho Lehtimäki, Guillaume Lettre, Jianjun Liu, Marja-Liisa Lokki, Mattias Lorentzon, Robert N Luben, Barbara Ludwig, , Paolo Manunta, Diana Marek, Michel Marre, Nicholas G Martin, Wendy L McArdle, Anne McCarthy, Barbara McKnight, Thomas Meitinger, Olle Melander, David Meyre, Kristian Midthjell, Grant W Montgomery, Mario A Morken, Andrew P Morris, Rosanda Mulić, Julius S Ngwa, Mari Nelis, Matt J Neville, Dale R Nyholt, Christopher J O'Donnell, Stephen O'Rahilly, Ken K Ong, Ben Oostra, Guillaume Paré, Alex N Parker, Markus Perola, Irene Pichler, Kirsi H Pietiläinen, Carl G P Platou, Ozren Polašek, Anneli Pouta, Suzanne Rafelt, Olli Raitakari, Nigel W Rayner, Martin Ridderstråle, Winfried Rief, Aimo Ruokonen, Neil R Robertson, Peter Rzehak, Veikko Salomaa, Alan R Sanders, Manjinder S Sandhu, Serena Sanna, Jouko Saramies, Markku J Savolainen, Susann Scherag, Sabine Schipf, Stefan Schreiber, Heribert Schunkert, Kaisa Silander, Juha Sinisalo, David S Siscovick, Jan H Smit, Nicole Soranzo, Ulla Sovio, Jonathan Stephens, Ida Surakka, Amy J Swift, Mari-Liis Tammesoo, Jean-Claude Tardif, Maris Teder-Laving, Tanya M Teslovich, John R Thompson, Brian Thomson, Anke Tönjes, Tiinamaija Tuomi, Joyce B J van Meurs, Gert-Jan van Ommen, Vincent Vatin, Jorma Viikari, Sophie Visvikis-Siest, Veronique Vitart, Carla I G Vogel, Benjamin F Voight, Lindsay L Waite, Henri Wallaschofski, G Bragi Walters, Elisabeth Widén, Susanna Wiegand, Sarah H Wild, Gonneke Willemsen, Daniel R Witte, Jacqueline C Witteman, Jianfeng Xu, Qunyuan Zhang, Lina Zgaga, Andreas Ziegler, Paavo Zitting, John P Beilby, I Sadaf Farooqi, Johannes Hebebrand, Heikki V Huikuri, Alan L James, Mika Kähönen, Douglas F Levinson, Fabio Macciardi, Markku S Nieminen, Claes Ohlsson, Lyle J Palmer, Paul M Ridker, Michael Stumvoll, Jacques S Beckmann, Heiner Boeing, Eric Boerwinkle, Dorret I Boomsma, Mark J Caulfield, Stephen J Chanock, Francis S Collins, L Adrienne Cupples, George Davey Smith, Jeanette Erdmann, Philippe Froguel, Henrik Grönberg, Ulf Gyllensten, Per Hall, Torben Hansen, Tamara B Harris, Andrew T Hattersley, Richard B Hayes, Joachim Heinrich, Frank B Hu, Kristian Hveem, Thomas Illig, Marjo-Riitta Järvelin, Jaakko Kaprio, Fredrik Karpe, Kay-Tee Khaw, Lambertus A Kiemeney, Heiko Krude, Markku Laakso, Debbie A Lawlor, Andres Metspalu, Patricia B Munroe, Willem H Ouwehand, Oluf Pedersen, Brenda W Penninx, Annette Peters, Peter P Pramstaller, Thomas Quertermous, Thomas Reinehr, Aila Rissanen, Igor Rudan, Nilesh J Samani, Peter E H Schwarz, Alan R Shuldiner, Timothy D Spector, Jaakko Tuomilehto, Manuela Uda, André Uitterlinden, Timo T Valle, Martin Wabitsch, Gérard Waeber, Nicholas J Wareham, Hugh Watkins, James F Wilson, Alan F Wright, M Carola Zillikens, Nilanjan Chatterjee, Steven A McCarroll, Shaun Purcell, Eric E Schadt, Peter M Visscher, Themistocles L Assimes, Ingrid B Borecki, Panos Deloukas, Caroline S Fox, Leif C Groop, Talin Haritunians, David J Hunter, Robert C Kaplan, Karen L Mohlke, Jeffrey R O'Connell, Leena Peltonen, David Schlessinger, David P Strachan, Cornelia M van Duijn, H-Erich Wichmann, Timothy M Frayling, Unnur Thorsteinsdottir, Gonçalo R Abecasis, Inês Barroso, Michael Boehnke, Kari Stefansson, Kari E North, Mark I McCarthy, Joel N Hirschhorn, Erik Ingelsson, Ruth J F Loos.
Nat. Genet.
PUBLISHED: 05-13-2010
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Obesity is globally prevalent and highly heritable, but its underlying genetic factors remain largely elusive. To identify genetic loci for obesity susceptibility, we examined associations between body mass index and ? 2.8 million SNPs in up to 123,865 individuals with targeted follow up of 42 SNPs in up to 125,931 additional individuals. We confirmed 14 known obesity susceptibility loci and identified 18 new loci associated with body mass index (P < 5 × 10??), one of which includes a copy number variant near GPRC5B. Some loci (at MC4R, POMC, SH2B1 and BDNF) map near key hypothalamic regulators of energy balance, and one of these loci is near GIPR, an incretin receptor. Furthermore, genes in other newly associated loci may provide new insights into human body weight regulation.
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Meta-analysis identifies 13 new loci associated with waist-hip ratio and reveals sexual dimorphism in the genetic basis of fat distribution.
Iris M Heid, Anne U Jackson, Joshua C Randall, Thomas W Winkler, Lu Qi, Valgerdur Steinthorsdottir, Gudmar Thorleifsson, M Carola Zillikens, Elizabeth K Speliotes, Reedik Mägi, Tsegaselassie Workalemahu, Charles C White, Nabila Bouatia-Naji, Tamara B Harris, Sonja I Berndt, Erik Ingelsson, Cristen J Willer, Michael N Weedon, Jian'an Luan, Sailaja Vedantam, Tonu Esko, Tuomas O Kilpeläinen, Zoltan Kutalik, Shengxu Li, Keri L Monda, Anna L Dixon, Christopher C Holmes, Lee M Kaplan, Liming Liang, Josine L Min, Miriam F Moffatt, Cliona Molony, George Nicholson, Eric E Schadt, Krina T Zondervan, Mary F Feitosa, Teresa Ferreira, Hana Lango Allen, Robert J Weyant, Eleanor Wheeler, Andrew R Wood, , Karol Estrada, Michael E Goddard, Guillaume Lettre, Massimo Mangino, Dale R Nyholt, Shaun Purcell, Albert Vernon Smith, Peter M Visscher, Jian Yang, Steven A McCarroll, James Nemesh, Benjamin F Voight, Devin Absher, Najaf Amin, Thor Aspelund, Lachlan Coin, Nicole L Glazer, Caroline Hayward, Nancy L Heard-Costa, Jouke-Jan Hottenga, Asa Johansson, Toby Johnson, Marika Kaakinen, Karen Kapur, Shamika Ketkar, Joshua W Knowles, Peter Kraft, Aldi T Kraja, Claudia Lamina, Michael F Leitzmann, Barbara McKnight, Andrew P Morris, Ken K Ong, John R B Perry, Marjolein J Peters, Ozren Polašek, Inga Prokopenko, Nigel W Rayner, Samuli Ripatti, Fernando Rivadeneira, Neil R Robertson, Serena Sanna, Ulla Sovio, Ida Surakka, Alexander Teumer, Sophie van Wingerden, Veronique Vitart, Jing Hua Zhao, Christine Cavalcanti-Proença, Peter S Chines, Eva Fisher, Jennifer R Kulzer, Cécile Lecoeur, Narisu Narisu, Camilla Sandholt, Laura J Scott, Kaisa Silander, Klaus Stark, Mari-Liis Tammesoo, Tanya M Teslovich, Nicholas John Timpson, Richard M Watanabe, Ryan Welch, Daniel I Chasman, Matthew N Cooper, John-Olov Jansson, Johannes Kettunen, Robert W Lawrence, Niina Pellikka, Markus Perola, Liesbeth Vandenput, Helene Alavere, Peter Almgren, Larry D Atwood, Amanda J Bennett, Reiner Biffar, Lori L Bonnycastle, Stefan R Bornstein, Thomas A Buchanan, Harry Campbell, Ian N M Day, Mariano Dei, Marcus Dörr, Paul Elliott, Michael R Erdos, Johan G Eriksson, Nelson B Freimer, Mao Fu, Stefan Gaget, Eco J C Geus, Anette P Gjesing, Harald Grallert, Jürgen Gräßler, Christopher J Groves, Candace Guiducci, Anna-Liisa Hartikainen, Neelam Hassanali, Aki S Havulinna, Karl-Heinz Herzig, Andrew A Hicks, Jennie Hui, Wilmar Igl, Pekka Jousilahti, Antti Jula, Eero Kajantie, Leena Kinnunen, Ivana Kolčić, Seppo Koskinen, Peter Kovacs, Heyo K Kroemer, Vjekoslav Krželj, Johanna Kuusisto, Kirsti Kvaloy, Jaana Laitinen, Olivier Lantieri, G Mark Lathrop, Marja-Liisa Lokki, Robert N Luben, Barbara Ludwig, Wendy L McArdle, Anne McCarthy, Mario A Morken, Mari Nelis, Matt J Neville, Guillaume Paré, Alex N Parker, John F Peden, Irene Pichler, Kirsi H Pietiläinen, Carl G P Platou, Anneli Pouta, Martin Ridderstråle, Nilesh J Samani, Jouko Saramies, Juha Sinisalo, Jan H Smit, Rona J Strawbridge, Heather M Stringham, Amy J Swift, Maris Teder-Laving, Brian Thomson, Gianluca Usala, Joyce B J van Meurs, Gert-Jan van Ommen, Vincent Vatin, Claudia B Volpato, Henri Wallaschofski, G Bragi Walters, Elisabeth Widén, Sarah H Wild, Gonneke Willemsen, Daniel R Witte, Lina Zgaga, Paavo Zitting, John P Beilby, Alan L James, Mika Kähönen, Terho Lehtimäki, Markku S Nieminen, Claes Ohlsson, Lyle J Palmer, Olli Raitakari, Paul M Ridker, Michael Stumvoll, Anke Tönjes, Jorma Viikari, Beverley Balkau, Yoav Ben-Shlomo, Richard N Bergman, Heiner Boeing, George Davey Smith, Shah Ebrahim, Philippe Froguel, Torben Hansen, Christian Hengstenberg, Kristian Hveem, Bo Isomaa, Torben Jørgensen, Fredrik Karpe, Kay-Tee Khaw, Markku Laakso, Debbie A Lawlor, Michel Marre, Thomas Meitinger, Andres Metspalu, Kristian Midthjell, Oluf Pedersen, Veikko Salomaa, Peter E H Schwarz, Tiinamaija Tuomi, Jaakko Tuomilehto, Timo T Valle, Nicholas J Wareham, Alice M Arnold, Jacques S Beckmann, Sven Bergmann, Eric Boerwinkle, Dorret I Boomsma, Mark J Caulfield, Francis S Collins, Gudny Eiriksdottir, Vilmundur Gudnason, Ulf Gyllensten, Anders Hamsten, Andrew T Hattersley, Albert Hofman, Frank B Hu, Thomas Illig, Carlos Iribarren, Marjo-Riitta Järvelin, W H Linda Kao, Jaakko Kaprio, Lenore J Launer, Patricia B Munroe, Ben Oostra, Brenda W Penninx, Peter P Pramstaller, Bruce M Psaty, Thomas Quertermous, Aila Rissanen, Igor Rudan, Alan R Shuldiner, Nicole Soranzo, Timothy D Spector, Ann-Christine Syvänen, Manuela Uda, André Uitterlinden, Henry Völzke, Peter Vollenweider, James F Wilson, Jacqueline C Witteman, Alan F Wright, Gonçalo R Abecasis, Michael Boehnke, Ingrid B Borecki, Panos Deloukas, Timothy M Frayling, Leif C Groop, Talin Haritunians, David J Hunter, Robert C Kaplan, Kari E North, Jeffrey R O'Connell, Leena Peltonen, David Schlessinger, David P Strachan, Joel N Hirschhorn, Themistocles L Assimes, H-Erich Wichmann, Unnur Thorsteinsdottir, Cornelia M van Duijn, Kari Stefansson, L Adrienne Cupples, Ruth J F Loos, Inês Barroso, Mark I McCarthy, Caroline S Fox, Karen L Mohlke, Cecilia M Lindgren.
Nat. Genet.
PUBLISHED: 05-06-2010
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Waist-hip ratio (WHR) is a measure of body fat distribution and a predictor of metabolic consequences independent of overall adiposity. WHR is heritable, but few genetic variants influencing this trait have been identified. We conducted a meta-analysis of 32 genome-wide association studies for WHR adjusted for body mass index (comprising up to 77,167 participants), following up 16 loci in an additional 29 studies (comprising up to 113,636 subjects). We identified 13 new loci in or near RSPO3, VEGFA, TBX15-WARS2, NFE2L3, GRB14, DNM3-PIGC, ITPR2-SSPN, LY86, HOXC13, ADAMTS9, ZNRF3-KREMEN1, NISCH-STAB1 and CPEB4 (P = 1.9 × 10?? to P = 1.8 × 10???) and the known signal at LYPLAL1. Seven of these loci exhibited marked sexual dimorphism, all with a stronger effect on WHR in women than men (P for sex difference = 1.9 × 10?³ to P = 1.2 × 10?¹³). These findings provide evidence for multiple loci that modulate body fat distribution independent of overall adiposity and reveal strong gene-by-sex interactions.
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Hundreds of variants clustered in genomic loci and biological pathways affect human height.
Hana Lango Allen, Karol Estrada, Guillaume Lettre, Sonja I Berndt, Michael N Weedon, Fernando Rivadeneira, Cristen J Willer, Anne U Jackson, Sailaja Vedantam, Soumya Raychaudhuri, Teresa Ferreira, Andrew R Wood, Robert J Weyant, Ayellet V Segrè, Elizabeth K Speliotes, Eleanor Wheeler, Nicole Soranzo, Ju-Hyun Park, Jian Yang, Daniel Gudbjartsson, Nancy L Heard-Costa, Joshua C Randall, Lu Qi, Albert Vernon Smith, Reedik Mägi, Tomi Pastinen, Liming Liang, Iris M Heid, Jian'an Luan, Gudmar Thorleifsson, Thomas W Winkler, Michael E Goddard, Ken Sin Lo, Cameron Palmer, Tsegaselassie Workalemahu, Yurii S Aulchenko, Asa Johansson, M Carola Zillikens, Mary F Feitosa, Tonu Esko, Toby Johnson, Shamika Ketkar, Peter Kraft, Massimo Mangino, Inga Prokopenko, Devin Absher, Eva Albrecht, Florian Ernst, Nicole L Glazer, Caroline Hayward, Jouke-Jan Hottenga, Kevin B Jacobs, Joshua W Knowles, Zoltan Kutalik, Keri L Monda, Ozren Polašek, Michael Preuss, Nigel W Rayner, Neil R Robertson, Valgerdur Steinthorsdottir, Jonathan P Tyrer, Benjamin F Voight, Fredrik Wiklund, Jianfeng Xu, Jing Hua Zhao, Dale R Nyholt, Niina Pellikka, Markus Perola, John R B Perry, Ida Surakka, Mari-Liis Tammesoo, Elizabeth L Altmaier, Najaf Amin, Thor Aspelund, Tushar Bhangale, Gabrielle Boucher, Daniel I Chasman, Constance Chen, Lachlan Coin, Matthew N Cooper, Anna L Dixon, Quince Gibson, Elin Grundberg, Ke Hao, M Juhani Junttila, Lee M Kaplan, Johannes Kettunen, Inke R König, Tony Kwan, Robert W Lawrence, Douglas F Levinson, Mattias Lorentzon, Barbara McKnight, Andrew P Morris, Martina Müller, Julius Suh Ngwa, Shaun Purcell, Suzanne Rafelt, Rany M Salem, Erika Salvi, Serena Sanna, Jianxin Shi, Ulla Sovio, John R Thompson, Michael C Turchin, Liesbeth Vandenput, Dominique J Verlaan, Veronique Vitart, Charles C White, Andreas Ziegler, Peter Almgren, Anthony J Balmforth, Harry Campbell, Lorena Citterio, Alessandro De Grandi, Anna Dominiczak, Jubao Duan, Paul Elliott, Roberto Elosua, Johan G Eriksson, Nelson B Freimer, Eco J C Geus, Nicola Glorioso, Shen Haiqing, Anna-Liisa Hartikainen, Aki S Havulinna, Andrew A Hicks, Jennie Hui, Wilmar Igl, Thomas Illig, Antti Jula, Eero Kajantie, Tuomas O Kilpeläinen, Markku Koiranen, Ivana Kolčić, Seppo Koskinen, Peter Kovacs, Jaana Laitinen, Jianjun Liu, Marja-Liisa Lokki, Ana Marušić, Andrea Maschio, Thomas Meitinger, Antonella Mulas, Guillaume Paré, Alex N Parker, John F Peden, Astrid Petersmann, Irene Pichler, Kirsi H Pietiläinen, Anneli Pouta, Martin Ridderstråle, Jerome I Rotter, Jennifer G Sambrook, Alan R Sanders, Carsten Oliver Schmidt, Juha Sinisalo, Jan H Smit, Heather M Stringham, G Bragi Walters, Elisabeth Widén, Sarah H Wild, Gonneke Willemsen, Laura Zagato, Lina Zgaga, Paavo Zitting, Helene Alavere, Martin Farrall, Wendy L McArdle, Mari Nelis, Marjolein J Peters, Samuli Ripatti, Joyce B J van Meurs, Katja K Aben, Kristin G Ardlie, Jacques S Beckmann, John P Beilby, Richard N Bergman, Sven Bergmann, Francis S Collins, Daniele Cusi, Martin den Heijer, Gudny Eiriksdottir, Pablo V Gejman, Alistair S Hall, Anders Hamsten, Heikki V Huikuri, Carlos Iribarren, Mika Kähönen, Jaakko Kaprio, Sekar Kathiresan, Lambertus Kiemeney, Thomas Kocher, Lenore J Launer, Terho Lehtimäki, Olle Melander, Tom H Mosley, Arthur W Musk, Markku S Nieminen, Christopher J O'Donnell, Claes Ohlsson, Ben Oostra, Lyle J Palmer, Olli Raitakari, Paul M Ridker, John D Rioux, Aila Rissanen, Carlo Rivolta, Heribert Schunkert, Alan R Shuldiner, David S Siscovick, Michael Stumvoll, Anke Tönjes, Jaakko Tuomilehto, Gert-Jan van Ommen, Jorma Viikari, Andrew C Heath, Nicholas G Martin, Grant W Montgomery, Michael A Province, Manfred Kayser, Alice M Arnold, Larry D Atwood, Eric Boerwinkle, Stephen J Chanock, Panos Deloukas, Christian Gieger, Henrik Grönberg, Per Hall, Andrew T Hattersley, Christian Hengstenberg, Wolfgang Hoffman, G Mark Lathrop, Veikko Salomaa, Stefan Schreiber, Manuela Uda, Dawn Waterworth, Alan F Wright, Themistocles L Assimes, Inês Barroso, Albert Hofman, Karen L Mohlke, Dorret I Boomsma, Mark J Caulfield, L Adrienne Cupples, Jeanette Erdmann, Caroline S Fox, Vilmundur Gudnason, Ulf Gyllensten, Tamara B Harris, Richard B Hayes, Marjo-Riitta Järvelin, Vincent Mooser, Patricia B Munroe, Willem H Ouwehand, Brenda W Penninx, Peter P Pramstaller, Thomas Quertermous, Igor Rudan, Nilesh J Samani, Timothy D Spector, Henry Völzke, Hugh Watkins, James F Wilson, Leif C Groop, Talin Haritunians, Frank B Hu, Robert C Kaplan, Andres Metspalu, Kari E North, David Schlessinger, Nicholas J Wareham, David J Hunter, Jeffrey R O'Connell, David P Strachan, H-Erich Wichmann, Ingrid B Borecki, Cornelia M van Duijn, Eric E Schadt, Unnur Thorsteinsdottir, Leena Peltonen, André G Uitterlinden, Peter M Visscher, Nilanjan Chatterjee, Ruth J F Loos, Michael Boehnke, Mark I McCarthy, Erik Ingelsson, Cecilia M Lindgren, Gonçalo R Abecasis, Kari Stefansson, Timothy M Frayling, Joel N Hirschhorn.
Nature
PUBLISHED: 04-23-2010
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Most common human traits and diseases have a polygenic pattern of inheritance: DNA sequence variants at many genetic loci influence the phenotype. Genome-wide association (GWA) studies have identified more than 600 variants associated with human traits, but these typically explain small fractions of phenotypic variation, raising questions about the use of further studies. Here, using 183,727 individuals, we show that hundreds of genetic variants, in at least 180 loci, influence adult height, a highly heritable and classic polygenic trait. The large number of loci reveals patterns with important implications for genetic studies of common human diseases and traits. First, the 180 loci are not random, but instead are enriched for genes that are connected in biological pathways (P = 0.016) and that underlie skeletal growth defects (P?
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Endothelial cell-selective adhesion molecule modulates atherosclerosis through plaque angiogenesis and monocyte-endothelial interaction.
Microvasc. Res.
PUBLISHED: 04-10-2010
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Endothelial cell-selective adhesion molecule (ESAM) is a new member of the immunoglobulin superfamily, which is expressed in vascular endothelial cells. Previous studies have demonstrated that ESAM regulates angiogenesis, endothelial permeability, and leukocyte transmigration. However, little is known concerning the role of ESAM in atherosclerosis. In this study, we assessed the effects of ESAM inactivation on atherosclerosis in mice. ESAM-/- mice were bred with apoE-/- mice to generate double knockout mice, and the aortic lesion size of apoE-/- and ESAM-/-apoE-/- mice was compared histologically. Although plasma cholesterol levels were higher in ESAM-/-apoE-/- mice, the lesion size was markedly smaller than in apoE-/- mice. ESAM-/-apoE-/- mice exhibited a decrease in the number of vasa vasorum and macrophages in the vessel wall. In vitro adhesion assays showed that THP-1 cells, which did not express ESAM, bound to the ESAM-coated culture plates, suggesting that ESAM may interact with heterophilic ligand(s) on monocytes. Moreover, downregulation of ESAM by siRNA in the endothelial monolayer diminished transendothelial migration of THP-1 cells. In conclusion, ESAM inactivation can reduce susceptibility to atherosclerosis by inhibiting plaque neovascularization and macrophage infiltration into the atheroma.
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Biological, clinical and population relevance of 95 loci for blood lipids.
Tanya M Teslovich, Kiran Musunuru, Albert V Smith, Andrew C Edmondson, Ioannis M Stylianou, Masahiro Koseki, James P Pirruccello, Samuli Ripatti, Daniel I Chasman, Cristen J Willer, Christopher T Johansen, Sigrid W Fouchier, Aaron Isaacs, Gina M Peloso, Maja Barbalic, Sally L Ricketts, Joshua C Bis, Yurii S Aulchenko, Gudmar Thorleifsson, Mary F Feitosa, John Chambers, Marju Orho-Melander, Olle Melander, Toby Johnson, Xiaohui Li, Xiuqing Guo, Mingyao Li, Yoon Shin Cho, Min Jin Go, Young Jin Kim, Jong-Young Lee, Taesung Park, Kyunga Kim, Xueling Sim, Rick Twee-Hee Ong, Damien C Croteau-Chonka, Leslie A Lange, Joshua D Smith, Kijoung Song, Jing Hua Zhao, Xin Yuan, Jian'an Luan, Claudia Lamina, Andreas Ziegler, Weihua Zhang, Robert Y L Zee, Alan F Wright, Jacqueline C M Witteman, James F Wilson, Gonneke Willemsen, H-Erich Wichmann, John B Whitfield, Dawn M Waterworth, Nicholas J Wareham, Gérard Waeber, Peter Vollenweider, Benjamin F Voight, Veronique Vitart, André G Uitterlinden, Manuela Uda, Jaakko Tuomilehto, John R Thompson, Toshiko Tanaka, Ida Surakka, Heather M Stringham, Tim D Spector, Nicole Soranzo, Johannes H Smit, Juha Sinisalo, Kaisa Silander, Eric J G Sijbrands, Angelo Scuteri, James Scott, David Schlessinger, Serena Sanna, Veikko Salomaa, Juha Saharinen, Chiara Sabatti, Aimo Ruokonen, Igor Rudan, Lynda M Rose, Robert Roberts, Mark Rieder, Bruce M Psaty, Peter P Pramstaller, Irene Pichler, Markus Perola, Brenda W J H Penninx, Nancy L Pedersen, Cristian Pattaro, Alex N Parker, Guillaume Paré, Ben A Oostra, Christopher J O'Donnell, Markku S Nieminen, Deborah A Nickerson, Grant W Montgomery, Thomas Meitinger, Ruth McPherson, Mark I McCarthy, Wendy McArdle, David Masson, Nicholas G Martin, Fabio Marroni, Massimo Mangino, Patrik K E Magnusson, Gavin Lucas, Robert Luben, Ruth J F Loos, Marja-Liisa Lokki, Guillaume Lettre, Claudia Langenberg, Lenore J Launer, Edward G Lakatta, Reijo Laaksonen, Kirsten O Kyvik, Florian Kronenberg, Inke R König, Kay-Tee Khaw, Jaakko Kaprio, Lee M Kaplan, Asa Johansson, Marjo-Riitta Järvelin, A Cecile J W Janssens, Erik Ingelsson, Wilmar Igl, G Kees Hovingh, Jouke-Jan Hottenga, Albert Hofman, Andrew A Hicks, Christian Hengstenberg, Iris M Heid, Caroline Hayward, Aki S Havulinna, Nicholas D Hastie, Tamara B Harris, Talin Haritunians, Alistair S Hall, Ulf Gyllensten, Candace Guiducci, Leif C Groop, Elena González, Christian Gieger, Nelson B Freimer, Luigi Ferrucci, Jeanette Erdmann, Paul Elliott, Kenechi G Ejebe, Angela Döring, Anna F Dominiczak, Serkalem Demissie, Panagiotis Deloukas, Eco J C de Geus, Ulf de Faire, Gabriel Crawford, Francis S Collins, Yii-Der I Chen, Mark J Caulfield, Harry Campbell, Noel P Burtt, Lori L Bonnycastle, Dorret I Boomsma, S Matthijs Boekholdt, Richard N Bergman, Inês Barroso, Stefania Bandinelli, Christie M Ballantyne, Themistocles L Assimes, Thomas Quertermous, David Altshuler, Mark Seielstad, Tien Y Wong, E-Shyong Tai, Alan B Feranil, Christopher W Kuzawa, Linda S Adair, Herman A Taylor, Ingrid B Borecki, Stacey B Gabriel, James G Wilson, Hilma Holm, Unnur Thorsteinsdottir, Vilmundur Gudnason, Ronald M Krauss, Karen L Mohlke, José M Ordovás, Patricia B Munroe, Jaspal S Kooner, Alan R Tall, Robert A Hegele, John J P Kastelein, Eric E Schadt, Jerome I Rotter, Eric Boerwinkle, David P Strachan, Vincent Mooser, Kari Stefansson, Muredach P Reilly, Nilesh J Samani, Heribert Schunkert, L Adrienne Cupples, Manjinder S Sandhu, Paul M Ridker, Daniel J Rader, Cornelia M van Duijn, Leena Peltonen, Gonçalo R Abecasis, Michael Boehnke, Sekar Kathiresan.
Nature
PUBLISHED: 02-25-2010
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Plasma concentrations of total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides are among the most important risk factors for coronary artery disease (CAD) and are targets for therapeutic intervention. We screened the genome for common variants associated with plasma lipids in >100,000 individuals of European ancestry. Here we report 95 significantly associated loci (P < 5 x 10(-8)), with 59 showing genome-wide significant association with lipid traits for the first time. The newly reported associations include single nucleotide polymorphisms (SNPs) near known lipid regulators (for example, CYP7A1, NPC1L1 and SCARB1) as well as in scores of loci not previously implicated in lipoprotein metabolism. The 95 loci contribute not only to normal variation in lipid traits but also to extreme lipid phenotypes and have an impact on lipid traits in three non-European populations (East Asians, South Asians and African Americans). Our results identify several novel loci associated with plasma lipids that are also associated with CAD. Finally, we validated three of the novel genes-GALNT2, PPP1R3B and TTC39B-with experiments in mouse models. Taken together, our findings provide the foundation to develop a broader biological understanding of lipoprotein metabolism and to identify new therapeutic opportunities for the prevention of CAD.
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Detailed physiologic characterization reveals diverse mechanisms for novel genetic Loci regulating glucose and insulin metabolism in humans.
Diabetes
PUBLISHED: 02-25-2010
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OBJECTIVE Recent genome-wide association studies have revealed loci associated with glucose and insulin-related traits. We aimed to characterize 19 such loci using detailed measures of insulin processing, secretion, and sensitivity to help elucidate their role in regulation of glucose control, insulin secretion and/or action. RESEARCH DESIGN AND METHODS We investigated associations of loci identified by the Meta-Analyses of Glucose and Insulin-related traits Consortium (MAGIC) with circulating proinsulin, measures of insulin secretion and sensitivity from oral glucose tolerance tests (OGTTs), euglycemic clamps, insulin suppression tests, or frequently sampled intravenous glucose tolerance tests in nondiabetic humans (n = 29,084). RESULTS The glucose-raising allele in MADD was associated with abnormal insulin processing (a dramatic effect on higher proinsulin levels, but no association with insulinogenic index) at extremely persuasive levels of statistical significance (P = 2.1 x 10(-71)). Defects in insulin processing and insulin secretion were seen in glucose-raising allele carriers at TCF7L2, SCL30A8, GIPR, and C2CD4B. Abnormalities in early insulin secretion were suggested in glucose-raising allele carriers at MTNR1B, GCK, FADS1, DGKB, and PROX1 (lower insulinogenic index; no association with proinsulin or insulin sensitivity). Two loci previously associated with fasting insulin (GCKR and IGF1) were associated with OGTT-derived insulin sensitivity indices in a consistent direction. CONCLUSIONS Genetic loci identified through their effect on hyperglycemia and/or hyperinsulinemia demonstrate considerable heterogeneity in associations with measures of insulin processing, secretion, and sensitivity. Our findings emphasize the importance of detailed physiological characterization of such loci for improved understanding of pathways associated with alterations in glucose homeostasis and eventually type 2 diabetes.
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Upregulation of the apelin-APJ pathway promotes neointima formation in the carotid ligation model in mouse.
Cardiovasc. Res.
PUBLISHED: 02-22-2010
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To investigate apelin-APJ (angiotensin receptor-like 1) signalling in vascular remodelling, we have examined the pathophysiological response to carotid ligation in apelin knockout mice.
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Role of endothelial cell-selective adhesion molecule in hematogeneous metastasis.
Microvasc. Res.
PUBLISHED: 02-04-2010
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The spread of malignant cells from a localized tumor is thought to be directly related to the number of microvessels in the tumor. The endothelial cell-selective adhesion molecule (ESAM) is a member of the immunoglobulin superfamily that mediates homophilic interactions between endothelial cells. Previous studies have indicated that ESAM regulates angiogenesis in the primary tumor growth and endothelial permeability. In this study, we aimed to further elucidate the role of ESAM in tumor metastasis through angiogenic processes. ESAM expression was higher in hypervascular metastatic tumor tissues than in normal tissues in human lungs. Cell culture studies found that conditioned medium from B16F10 melanoma cells increased ESAM expression in endothelial cells and promoted endothelial migration and tube formation. The B16F10 medium-induced endothelial migration and tube formation were significantly attenuated when ESAM was downregulated by siRNA transfection. Intravenous injection of B16F10 cells into ESAM+/+ and ESAM-/- mice for comparison of metastatic potential resulted in the number of metastatic lung nodules in ESAM-/- mice being 83% lower than of those in ESAM+/+ mice. The microvascular density in the tumor was also lower in ESAM-/- than in ESAM+/+ mice. These findings indicate that ESAM regulates tumor metastasis through endothelial cell migration and tube formation in metastatic nodules. Inhibition of ESAM may therefore inhibit tumor metastasis by inhibiting the angiogenic processes.
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Persistent donor cell gene expression among human induced pluripotent stem cells contributes to differences with human embryonic stem cells.
PLoS ONE
PUBLISHED: 02-01-2010
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Human induced pluripotent stem cells (hiPSCs) generated by de-differentiation of adult somatic cells offer potential solutions for the ethical issues surrounding human embryonic stem cells (hESCs), as well as their immunologic rejection after cellular transplantation. However, although hiPSCs have been described as "embryonic stem cell-like", these cells have a distinct gene expression pattern compared to hESCs, making incomplete reprogramming a potential pitfall. It is unclear to what degree the difference in tissue of origin may contribute to these gene expression differences. To answer these important questions, a careful transcriptional profiling analysis is necessary to investigate the exact reprogramming state of hiPSCs, as well as analysis of the impression, if any, of the tissue of origin on the resulting hiPSCs. In this study, we compare the gene profiles of hiPSCs derived from fetal fibroblasts, neonatal fibroblasts, adipose stem cells, and keratinocytes to their corresponding donor cells and hESCs. Our analysis elucidates the overall degree of reprogramming within each hiPSC line, as well as the "distance" between each hiPSC line and its donor cell. We further identify genes that have a similar mode of regulation in hiPSCs and their corresponding donor cells compared to hESCs, allowing us to specify core sets of donor genes that continue to be expressed in each hiPSC line. We report that residual gene expression of the donor cell type contributes significantly to the differences among hiPSCs and hESCs, and adds to the incompleteness in reprogramming. Specifically, our analysis reveals that fetal fibroblast-derived hiPSCs are closer to hESCs, followed by adipose, neonatal fibroblast, and keratinocyte-derived hiPSCs.
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Apelin is necessary for the maintenance of insulin sensitivity.
Am. J. Physiol. Endocrinol. Metab.
PUBLISHED: 10-27-2009
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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 apelins 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. Apelins effects on glucose uptake and Akt phosphorylation are in part mediated by a G(i) and AMPK-dependent pathway.
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Endogenous regulation of cardiovascular function by apelin-APJ.
Am. J. Physiol. Heart Circ. Physiol.
PUBLISHED: 09-18-2009
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Studies have shown significant cardiovascular effects of exogenous apelin administration, including the potent activation of cardiac contraction. However, the role of the endogenous apelin-APJ pathway is less clear. To study the loss of endogenous apelin-APJ signaling, we generated mice lacking either the ligand (apelin) or the receptor (APJ). Apelin-deficient mice were viable, fertile, and showed normal development. In contrast, APJ-deficient mice were not born in the expected Mendelian ratio, and many showed cardiovascular developmental defects. Under basal conditions, both apelin and APJ null mice that survived to adulthood manifested modest decrements in contractile function. However, with exercise stress both mutant lines demonstrated consistent and striking decreases in exercise capacity. To explain these findings, we explored the role of autocrine signaling in vitro using field stimulation of isolated left ventricular cardiomyocytes lacking either apelin or APJ. Both groups manifested less sarcomeric shortening and impaired velocity of contraction and relaxation with no difference in calcium transient. Taken together, these results demonstrate that endogenous apelin-APJ signaling plays a modest role in maintaining basal cardiac function in adult mice with a more substantive role during conditions of stress. In addition, an autocrine pathway seems to exist in myocardial cells, the ablation of which reduces cellular contraction without change in calcium transient. Finally, differences in the developmental phenotype between apelin and APJ null mice suggest the possibility of undiscovered APJ ligands or ligand-independent effects of APJ.
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The adhesion molecule esam1 is a novel hematopoietic stem cell marker.
Stem Cells
PUBLISHED: 08-12-2009
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Hematopoietic stem cells (HSCs) have been highly enriched using combinations of 12-14 surface markers. Genes specifically expressed by HSCs as compared with other multipotent progenitors may yield new stem cell enrichment markers, as well as elucidate self-renewal and differentiation mechanisms. We previously reported that multiple cell surface molecules are enriched on mouse HSCs compared with more differentiated progeny. Here, we present a definitive expression profile of the cell adhesion molecule endothelial cell-selective adhesion molecule (Esam1) in hematopoietic cells using reverse transcription-quantitative polymerase chain reaction and flow cytometry studies. We found Esam1 to be highly and selectively expressed by HSCs from mouse bone marrow (BM). Esam1 was also a viable positive HSC marker in fetal, young, and aged mice, as well as in mice of several different strains. In addition, we found robust levels of Esam1 transcripts in purified human HSCs. Esam1(-/-) mice do not exhibit severe hematopoietic defects; however, Esam1(-/-) BM has a greater frequency of HSCs and fewer T cells. HSCs from Esam1(-/-) mice give rise to more granulocyte/monocytes in culture and a higher T cell:B cell ratio upon transplantation into congenic mice. These studies identify Esam1 as a novel, widely applicable HSC-selective marker and suggest that Esam1 may play roles in both HSC proliferation and lineage decisions.
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Role of endothelial lipase in plasma HDL levels in a murine model of hypertriglyceridemia.
J. Atheroscler. Thromb.
PUBLISHED: 08-11-2009
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Hypertriglyceridemia is the most common cause of low plasma high-density lipoprotein cholesterol (HDL-C) levels; however, the correlation between high triglyceride (TG) and low HDL-C remains unclear. Endothelial lipase (EL) is a determinant of plasma HDL levels. We investigated the role of EL in HDL metabolism in a murine model of acute hypertriglyceridemia.
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Peroxisome proliferator-activated receptor gamma polymorphisms and coronary heart disease.
PPAR Res
PUBLISHED: 06-11-2009
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Single nucleotide polymorphisms (SNPs) in the peroxisome proliferator-activated receptor gamma (PPARG) gene have been associated with cardiovascular risk factors, particularly obesity and diabetes. We assessed the relationship between 4 PPARG SNPs (C-681G, C-689T, Pro12Ala, and C1431T) and coronary heart disease (CHD) in the PRIME (249 cases/494 controls, only men) and ADVANCE (1,076 cases/805 controls, men or women) studies. In PRIME, homozygote individuals for the minor allele of the PPARG C-689T, Pro12Ala, and C1431T SNPs tended to have a higher risk of CHD than homozygote individuals for the frequent allele (adjusted OR [95% CI] = 3.43 [0.96-12.27], P = .058, 3.41 [0.95-12.22], P = .060 and 5.10 [0.99-26.37], P = .050, resp.). No such association could be detected in ADVANCE. Haplotype distributions were similar in cases and control in both studies. A meta-analysis on the Pro12Ala SNP, based on our data and 11 other published association studies (6,898 CHD cases/11,287 controls), revealed that there was no evidence for a significant association under the dominant model (OR = 0.99 [0.92-1.07], P = .82). However, there was a borderline association under the recessive model (OR = 1.29 [0.99-1.67], P = .06) that became significant when considering men only (OR = 1.73 [1.20-2.48], P = .003). In conclusion, the PPARG Ala12Ala genotype might be associated with a higher CHD risk in men but further confirmation studies are needed.
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Characterizing the admixed African ancestry of African Americans.
Genome Biol.
PUBLISHED: 05-27-2009
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Accurate, high-throughput genotyping allows the fine characterization of genetic ancestry. Here we applied recently developed statistical and computational techniques to the question of African ancestry in African Americans by using data on more than 450,000 single-nucleotide polymorphisms (SNPs) genotyped in 94 Africans of diverse geographic origins included in the HGDP, as well as 136 African Americans and 38 European Americans participating in the Atherosclerotic Disease Vascular Function and Genetic Epidemiology (ADVANCE) study. To focus on African ancestry, we reduced the data to include only those genotypes in each African American determined statistically to be African in origin.
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Identification of ARIA regulating endothelial apoptosis and angiogenesis by modulating proteasomal degradation of cIAP-1 and cIAP-2.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 05-01-2009
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Endothelial apoptosis is a pivotal process for angiogenesis during embryogenesis as well as postnatal life. By using a retrovirus-mediated signal sequence trap method, we identified a previously undescribed gene, termed ARIA (apoptosis regulator through modulating IAP expression), which regulates endothelial apoptosis and angiogenesis. ARIA was expressed in blood vessels during mouse embryogenesis, as well as in endothelial cells both in vitro and in vivo. ARIA is a unique protein with no homology to previously reported conserved domain structures. Knockdown of ARIA in HUVECs by using small interfering RNA significantly reduced endothelial apoptosis without affecting either cell migration or proliferation. ARIA knockdown significantly increased inhibitor of apoptosis (cIAP)-1 and cIAP-2 protein expression, although their mRNA expression was not changed. Simultaneous knockdown of cIAP-1 and cIAP-2 abolished the antiapoptotic effect of ARIA knockdown. Using yeast 2-hybrid screening, we identified the interaction of ARIA with 20S proteasome subunit alpha-7. Thereafter, we found that cIAP-1 and cIAP-2 were degraded by proteasomes in endothelial cells under normal condition. Overexpression of ARIA significantly reduced cIAP-1 expression, and this reduction was abolished by proteasomal inhibition in BAECs. Also, knockdown of ARIA demonstrated an effect similar to proteasomal inhibition with respect to not only expression but also subcellular localization of cIAP-1 and cIAP-2. In vivo angiogenesis studied by Matrigel-plug assay, mouse ischemic retinopathy model, and tumor xenograft model was significantly enhanced by ARIA knockdown. Together, our data indicate that ARIA is a unique factor regulating endothelial apoptosis, as well as angiogenesis, presumably through modulating proteasomal degradation of cIAP-1 and cIAP-2 in endothelial cells.
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Apelin prevents aortic aneurysm formation by inhibiting macrophage inflammation.
Am. J. Physiol. Heart Circ. Physiol.
PUBLISHED: 03-20-2009
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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.
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Admixture mapping of quantitative trait loci for blood lipids in African-Americans.
Hum. Mol. Genet.
PUBLISHED: 03-20-2009
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Blood lipid levels, including low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG), are highly heritable traits and major risk factors for atherosclerotic cardiovascular disease (CVD). Using individual ancestry estimates at marker locations across the genome, we present a novel quantitative admixture mapping analysis of all three lipid traits in a large sample of African-Americans from the Family Blood Pressure Program. Regression analysis was performed with both total and marker-location-specific European ancestry as explanatory variables, along with demographic covariates. Robust permutation analysis was used to assess statistical significance. Overall European ancestry was significantly correlated with HDL-C (negatively) and TG (positively), but not with LDL-C. We found strong evidence for a novel locus underlying HDL-C on chromosome 8q, which correlated negatively with European ancestry (P = .0014); the same location also showed positive correlation of European ancestry with TG levels. A region on chromosome 14q also showed significant negative correlation between HDL-C levels and European ancestry. On chromosome 15q, a suggestive negative correlation of European ancestry with TG and positive correlation with HDL-C was observed. Results with LDL-C were less significant overall. We also found significant evidence for genome-wide ancestry effects underlying the joint distribution of HDL-C and TG, not fully explained by the locus on chromosome 8. Our results are consistent with a genetic contribution to and may explain the healthier HDL-C and TG profiles found in Blacks versus Whites. The identified regions provide locations for follow-up studies of genetic variants underlying lipid variation in African-Americans and possibly other populations.
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Insulin resistance independently predicts the progression of coronary artery calcification.
Am. Heart J.
PUBLISHED: 02-07-2009
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Change in coronary artery calcification is a surrogate marker of subclinical coronary artery disease (CAD). In the only large prospective study, CAD risk factors predicted progression of coronary artery calcium (CAC).
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Targeted inactivation of endothelial lipase attenuates lung allergic inflammation through raising plasma HDL level and inhibiting eosinophil infiltration.
Am. J. Physiol. Lung Cell Mol. Physiol.
PUBLISHED: 01-23-2009
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Endothelial lipase (EL) is a novel phospholipase that determines plasma high-density lipoprotein cholesterol (HDL-C) levels. We have investigated the role of HDL-C in lung allergic inflammation by using EL knockout (EL-KO) mice that are high in HDL-C. EL-KO and wild-type control mice were sensitized and challenged with ovalbumin to evoke eosinophilic inflammation in the lung. EL was expressed in epithelial cells, alveolar type II cells, and endothelial cells in the lung, and its expression was upregulated during inflammation. Concomitant with attenuated hyperresponsiveness of the airway smooth muscles, the number of eosinophils in bronchoalveolar lavage and the expression of VCAM-1 were lower in EL-KO mice than in control mice. HDL reduced cytokine-induced VCAM-1 expression in cultured endothelial cells. When plasma HDL levels were decreased to similar levels in both mouse groups by adenovirus-mediated overexpression of EL, however, eosinophil infiltration was still lower in EL-KO mice. In vitro adhesion assays revealed that EL expression on the cell surface promoted the interaction of eosinophils through the ligand-binding function of EL. In summary, targeted inactivation of EL attenuated allergic inflammation in the lung, and the protective effects in EL-KO mice were associated with high plasma HDL levels, downregulation of VCAM-1, and loss of the direct ligand-binding function of EL. Thus EL is a novel modulator of the progression of allergic asthma.
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Ontogeny of apelin and its receptor in the rodent gastrointestinal tract.
Regul. Pept.
PUBLISHED: 01-22-2009
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Apelin is the endogenous ligand for the APJ receptor and both apelin and APJ are expressed in the gastrointestinal (GI) tract. The aim of this study was to define ontogeny of apelin and APJ in the developing rodent GI tract by measuring expression levels and characterizing abundance and cellular localization at an embryonic stage (E18.5 or E21), two postnatal stages (P4, P16) and in the adult. Apelin and APJ mRNA levels were measured by real time RT-PCR, apelin and APJ-containing cells were identified by immunohistochemical (IHC) staining. Gastric, duodenal and colonic apelin and APJ mRNA levels were highest at birth and declined postnatally. In the postnatal rat stomach, few apelin peptide-containing cells were identified, the density of gastric apelin-containing cells increased progressively after weaning and into adulthood. A robust APJ immunostaining was observed postnatally in the epithelium, intestinal goblet cells and in smooth muscle cells. In the adult rat, APJ immunostaining in the surface epithelium and goblet cells decreased markedly. During the early postnatal period, in an apelin-deficient mouse, APJ expression and immunostaining in the gut were reduced suggesting that apelin regulates APJ. Together, our data support a role for the apelin-APJ system in the regulation of smooth muscle, epithelial and goblet cell function in the GI tract.
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Large-scale association analysis identifies new risk loci for coronary artery disease.
, Panos Deloukas, Stavroula Kanoni, Christina Willenborg, Martin Farrall, Themistocles L Assimes, John R Thompson, Erik Ingelsson, Danish Saleheen, Jeanette Erdmann, Benjamin A Goldstein, Kathleen Stirrups, Inke R König, Jean-Baptiste Cazier, Asa Johansson, Alistair S Hall, Jong-Young Lee, Cristen J Willer, John C Chambers, Tonu Esko, Lasse Folkersen, Anuj Goel, Elin Grundberg, Aki S Havulinna, Weang K Ho, Jemma C Hopewell, Niclas Eriksson, Marcus E Kleber, Kati Kristiansson, Per Lundmark, Leo-Pekka Lyytikäinen, Suzanne Rafelt, Dmitry Shungin, Rona J Strawbridge, Gudmar Thorleifsson, Emmi Tikkanen, Natalie Van Zuydam, Benjamin F Voight, Lindsay L Waite, Weihua Zhang, Andreas Ziegler, Devin Absher, David Altshuler, Anthony J Balmforth, Inês Barroso, Peter S Braund, Christof Burgdorf, Simone Claudi-Boehm, David Cox, Maria Dimitriou, Ron Do, Alex S F Doney, NourEddine El Mokhtari, Per Eriksson, Krista Fischer, Pierre Fontanillas, Anders Franco-Cereceda, Bruna Gigante, Leif Groop, Stefan Gustafsson, Jörg Hager, Göran Hallmans, Bok-Ghee Han, Sarah E Hunt, Hyun M Kang, Thomas Illig, Thorsten Kessler, Joshua W Knowles, Genovefa Kolovou, Johanna Kuusisto, Claudia Langenberg, Cordelia Langford, Karin Leander, Marja-Liisa Lokki, Anders Lundmark, Mark I McCarthy, Christa Meisinger, Olle Melander, Evelin Mihailov, Seraya Maouche, Andrew D Morris, Martina Müller-Nurasyid, Kjell Nikus, John F Peden, N William Rayner, Asif Rasheed, Silke Rosinger, Diana Rubin, Moritz P Rumpf, Arne Schäfer, Mohan Sivananthan, Ci Song, Alexandre F R Stewart, Sian-Tsung Tan, Gudmundur Thorgeirsson, C Ellen van der Schoot, Peter J Wagner, George A Wells, Philipp S Wild, Tsun-Po Yang, Philippe Amouyel, Dominique Arveiler, Hanneke Basart, Michael Boehnke, Eric Boerwinkle, Paolo Brambilla, Francois Cambien, Adrienne L Cupples, Ulf de Faire, Abbas Dehghan, Patrick Diemert, Stephen E Epstein, Alun Evans, Marco M Ferrario, Jean Ferrières, Dominique Gauguier, Alan S Go, Alison H Goodall, Villi Gudnason, Stanley L Hazen, Hilma Holm, Carlos Iribarren, Yangsoo Jang, Mika Kähönen, Frank Kee, Hyo-Soo Kim, Norman Klopp, Wolfgang Koenig, Wolfgang Kratzer, Kari Kuulasmaa, Markku Laakso, Reijo Laaksonen, Ji-Young Lee, Lars Lind, Willem H Ouwehand, Sarah Parish, Jeong E Park, Nancy L Pedersen, Annette Peters, Thomas Quertermous, Daniel J Rader, Veikko Salomaa, Eric Schadt, Svati H Shah, Juha Sinisalo, Klaus Stark, Kari Stefansson, David-Alexandre Trégouët, Jarmo Virtamo, Lars Wallentin, Nicholas Wareham, Martina E Zimmermann, Markku S Nieminen, Christian Hengstenberg, Manjinder S Sandhu, Tomi Pastinen, Ann-Christine Syvänen, G Kees Hovingh, George Dedoussis, Paul W Franks, Terho Lehtimäki, Andres Metspalu, Pierre A Zalloua, Agneta Siegbahn, Stefan Schreiber, Samuli Ripatti, Stefan S Blankenberg, Markus Perola, Robert Clarke, Bernhard O Boehm, Christopher O'Donnell, Muredach P Reilly, Winfried März, Rory Collins, Sekar Kathiresan, Anders Hamsten, Jaspal S Kooner, Unnur Thorsteinsdottir, John Danesh, Colin N A Palmer, Robert Roberts, Hugh Watkins, Heribert Schunkert, Nilesh J Samani.
Nat. Genet.
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Coronary artery disease (CAD) is the commonest cause of death. Here, we report an association analysis in 63,746 CAD cases and 130,681 controls identifying 15 loci reaching genome-wide significance, taking the number of susceptibility loci for CAD to 46, and a further 104 independent variants (r(2) < 0.2) strongly associated with CAD at a 5% false discovery rate (FDR). Together, these variants explain approximately 10.6% of CAD heritability. Of the 46 genome-wide significant lead SNPs, 12 show a significant association with a lipid trait, and 5 show a significant association with blood pressure, but none is significantly associated with diabetes. Network analysis with 233 candidate genes (loci at 10% FDR) generated 5 interaction networks comprising 85% of these putative genes involved in CAD. The four most significant pathways mapping to these networks are linked to lipid metabolism and inflammation, underscoring the causal role of these activities in the genetic etiology of CAD. Our study provides insights into the genetic basis of CAD and identifies key biological pathways.
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Loss of CDKN2B promotes p53-dependent smooth muscle cell apoptosis and aneurysm formation.
Arterioscler. Thromb. Vasc. Biol.
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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.
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Measurement of insulin-mediated glucose uptake: direct comparison of the modified insulin suppression test and the euglycemic, hyperinsulinemic clamp.
Metab. Clin. Exp.
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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.
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Common ALDH2 genetic variants predict development of hypertension in the SAPPHIRe prospective cohort: gene-environmental interaction with alcohol consumption.
BMC Cardiovasc Disord
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Genetic variants near/within the ALDH2 gene encoding the mitochondrial aldehyde dehydrogenase 2 have been associated with blood pressure and hypertension in several case-control association studies in East Asian populations.
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Apelin enhances directed cardiac differentiation of mouse and human embryonic stem cells.
PLoS ONE
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Apelin is a peptide ligand for an orphan G-protein coupled receptor (APJ receptor) and serves as a critical gradient for migration of mesodermal cells fated to contribute to the myocardial lineage. The present study was designed to establish a robust cardiac differentiation protocol, specifically, to evaluate the effect of apelin on directed differentiation of mouse and human embryonic stem cells (mESCs and hESCs) into cardiac lineage. Different concentrations of apelin (50, 100, 500 nM) were evaluated to determine its differentiation potential. The optimized dose of apelin was then combined with mesodermal differentiation factors, including BMP-4, activin-A, and bFGF, in a developmentally specific temporal sequence to examine the synergistic effects on cardiac differentiation. Cellular, molecular, and physiologic characteristics of the apelin-induced contractile embryoid bodies (EBs) were analyzed. It was found that 100 nM apelin resulted in highest percentage of contractile EB for mESCs while 500 nM had the highest effects on hESCs. Functionally, the contractile frequency of mESCs-derived EBs (mEBs) responded appropriately to increasing concentration of isoprenaline and diltiazem. Positive phenotype of cardiac specific markers was confirmed in the apelin-treated groups. The protocol, consisting of apelin and mesodermal differentiation factors, induced contractility in significantly higher percentage of hESC-derived EBs (hEBs), up-regulated cardiac-specific genes and cell surface markers, and increased the contractile force. In conclusion, we have demonstrated that the treatment of apelin enhanced cardiac differentiation of mouse and human ESCs and exhibited synergistic effects with mesodermal differentiation factors.
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Genetic variation in the carbonyl reductase 3 gene confers risk of type 2 diabetes and insulin resistance: a potential regulator of adipogenesis.
J. Mol. Med.
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Prostaglandins are potent modulators of insulin sensitivity. We systemically evaluated the association of 61 tag single-nucleotide polymorphisms (SNP) in 14 genes involved in prostaglandin metabolism with type 2 diabetes. Among all genotyped SNPs, rs10483032 in the CBR3 (carbonyl reductase 3) gene, which encodes for an enzyme converting prostaglandin E(2) to prostaglandin F2(?), was associated with type 2 diabetes in 760 type 2 diabetic cases and 760 controls (stage-1 study) (P?=?2.0?×?10(-4)). The association was validated in 1,615 cases and 1,162 controls (stage-2 study) (P?=?0.009). The A allele at rs10483032 was associated with increased risk of type 2 diabetes (odds ratio?=?1.29; 95% confidence interval?=?1.14-1.47; combined P?
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.