Metabolic syndrome (MetSyn) is a group of metabolic conditions that occur together and promote the development of cardiovascular disease (CVD) and type 2 diabetes. Although various criteria for defining MetSyn exist, disease conditions include abdominal obesity, insulin resistance, elevated serum triglyceride levels, depressed serum high-density lipoprotein (HDL) levels, elevated blood glucose levels and hypertension. The incidence of MetSyn is predicted to increase as obesity has become a worldwide epidemic. This increase may have detrimental effects and may actually reverse the trend of decreasing CVD in the US. Recent genome-wide association studies (GWAS) have identified over 400 genomic loci that are associated with obesity, diabetes, CVD and cardiometabolic traits. However, most of the underlying genes and the related mechanisms of how these loci contribute to the disease process remain unknown. This proposal outlines an integrated systems genetics approach to identify causal genes and pathways underlying the GWAS loci by combining data from extensively phenotyped human and mouse cohorts that are part of the Metabolic Syndrome in Men (METSIM) and Hybrid Mouse Diversity Panel (HMDP) studies, respectively. It also outlines an extensive career development plan for Dr. Mete Civelek to complete postdoctoral training under the mentorship of Dr. Aldons Lusis and transition to an independent academic position by establishing a multi-disciplinary research program in cardiovascular pathophysiology. During the K99 phase of the award, the PI will measure adipose mRNA and microRNA abundance using expression arrays and next generation profiling from the human subjects which will be genotyped using high density SNP arrays. Similar measurements will be performed in mice. Significant genotype-expression trait associations at GWAS loci will be used to predict genes causally involved in the development of disease. Co- expression networks will be constructed from expression data and will be used to predict the relationships of causal genes with known pathways. Having predicted the causal genes and their functions during the K99 phase of the award, the PI will then test these predictions, using in vitro and in vivo experiments during the R00 phase of the award. The preliminary results have identified CPEB4, which encodes an RNA binding protein, as the causal gene underlying the significant association signal in the chromosome 5 locus for waist-to-hip ratio in humans. In vitro studies and bioinformatics approaches will identify the mRNAs that are targeted by this RNA binding protein. In vivo studies using adipocyte specific Cpeb4 transgenic and knock-out mice will identify its role in the regulation of fat mass and associated metabolic traits. The overall goal of the proposed studies is to integrate system biology and molecular analysis in both in vitro and in vivo experiments, leading to mechanistic understandings of the gene networks that are perturbed by disease-associated genetic variants that result in cardiometabolic disorders.

Public Health Relevance

Metabolic Syndrome is a primary cause of cardiovascular disease and diabetes. Understanding the biologic networks that underlie the complex interactions in metabolic syndrome traits is required for disease prevention, diagnosis, and treatment.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Transition Award (R00)
Project #
5R00HL121172-05
Application #
9415058
Study Section
Special Emphasis Panel (NSS)
Program Officer
Olive, Michelle
Project Start
2014-05-01
Project End
2019-01-31
Budget Start
2018-02-01
Budget End
2019-01-31
Support Year
5
Fiscal Year
2018
Total Cost
Indirect Cost
Name
University of Virginia
Department
Public Health & Prev Medicine
Type
Schools of Medicine
DUNS #
065391526
City
Charlottesville
State
VA
Country
United States
Zip Code
22904
Pan, David Z; Garske, Kristina M; Alvarez, Marcus et al. (2018) Integration of human adipocyte chromosomal interactions with adipose gene expression prioritizes obesity-related genes from GWAS. Nat Commun 9:1512
Small, Kerrin S; Todor?evi?, Marijana; Civelek, Mete et al. (2018) Regulatory variants at KLF14 influence type 2 diabetes risk via a female-specific effect on adipocyte size and body composition. Nat Genet 50:572-580
Krause, Matthew D; Huang, Ru-Ting; Wu, David et al. (2018) Genetic variant at coronary artery disease and ischemic stroke locus 1p32.2 regulates endothelial responses to hemodynamics. Proc Natl Acad Sci U S A 115:E11349-E11358
Seldin, Marcus M; Koplev, Simon; Rajbhandari, Prashant et al. (2018) A Strategy for Discovery of Endocrine Interactions with Application to Whole-Body Metabolism. Cell Metab 27:1138-1155.e6
Schugar, Rebecca C; Shih, Diana M; Warrier, Manya et al. (2017) The TMAO-Producing Enzyme Flavin-Containing Monooxygenase 3 Regulates Obesity and the Beiging of White Adipose Tissue. Cell Rep 19:2451-2461
Civelek, Mete (2017) A Smoking-Associated miRNA-mRNA Coexpression Network. Circ Cardiovasc Genet 10:
Civelek, Mete; Wu, Ying; Pan, Calvin et al. (2017) Genetic Regulation of Adipose Gene Expression and Cardio-Metabolic Traits. Am J Hum Genet 100:428-443
Kessler, Thorsten; Wobst, Jana; Wolf, Bernhard et al. (2017) Functional Characterization of the GUCY1A3 Coronary Artery Disease Risk Locus. Circulation 136:476-489
Cannon, Maren E; Duan, Qing; Wu, Ying et al. (2017) Trans-ancestry Fine Mapping and Molecular Assays Identify Regulatory Variants at the ANGPTL8 HDL-C GWAS Locus. G3 (Bethesda) 7:3217-3227
Brænne, Ingrid; Civelek, Mete; Vilne, Baiba et al. (2015) Prediction of Causal Candidate Genes in Coronary Artery Disease Loci. Arterioscler Thromb Vasc Biol 35:2207-17