Abstract
Context: Chemerin is a new adipokine associated with obesity and the metabolic syndrome. Gene expression levels of chemerin were elevated in the adipose depots of obese compared with lean animals and was markedly elevated during differentiation of fibroblasts into mature adipocytes.
Objective: To identify factors that affect the regulation and potential function of chemerin using a genetics approach.
Design, setting, patients and intervention: Plasma chemerin levels were measured in subjects from the San Antonio Family Heart Study (SAFHS), a large family-based genetic epidemiological study including 1354 Mexican American individuals. Individuals were randomly sampled without regard to phenotype or disease status.
Main Outcome Measures: A genome wide association analysis using 542,944 SNPs in a subset of 523 of the same subjects was undertaken. The effect of chemerin on angiogenesis was measured using human endothelial cells and interstitial cells in co-culture in a specially formulated medium.
Results: Serum chemerin levels were found to be highly heritable (h2 = 0.25; P = 1.4 x 10−9). The SNP showing strongest evidence of association (rs347344; P = 1.4 x 10−6) was located within the gene encoding EDIL3, which has a known role in angiogenesis. Functional angiogenesis assays in human endothelial cells confirmed that chemerin significantly mediated the formation of blood vessels to a similar extent as VEGF.
Conclusion: Here we demonstrate for the first time that plasma chemerin levels are significantly heritable and identified a novel role for chemerin as a stimulator of angiogenesis.
All-Cause and Cardiovascular Mortality among Mexican-American and Non-Hispanic White Older Participants in the San Antonio Heart Study-- Evidence against the "Hispanic Paradox"