Association between variants in the genes for leptin, leptin receptor, and proopiomelanocortin with chronic heart failure in the Czech population

Abstract

Patients with chronic heart failure (CHF) express enhanced catabolic metabolism finally resulting in overall weight loss, whereas adipokines might play a crucial role in signaling among tissues. The aim of this study was to investigate the possible associations of defined variability in leptin (dbSNP ID rs7799039), proopiomelanocortin (dbSNP ID rs3754860 and dbSNP ID rs1009388), and leptin receptor gene (dbSNP rs1137101) with CHF and evaluate their potential as the CHF susceptibility genes. The case-control study comprised a total of 372 patients of Caucasian origin with chronic heart failure (New York Heart Association [NYHA] functional classes II-IV, ejection fraction (EF) <40%) and 407 healthy controls. They were genotyped for the leptin (LEP) -2548 G/A, leptin receptor (LEPR) Gln223Arg, and proopiomelanocortin (POMC) RsaI (5′-untranslated region) and C1032G variants (intron 1) using PCR-based methodology. No case-control differences in genotype as well as allele frequencies were observed between CHF patients and controls. We constructed POMC RsaI/C1032G haplotypes, having found no significant association with body mass index (BMI), left ventricle ejection fraction (LVEF), left ventricle hypertrophy (LVH) and diabetes mellitus (DM). Multivariate regression analyses revealed an approximately 2-fold risk for NYHA class IV associated with the LEPR Gln223Arg (P = 0.0000001, odds ratio [OR] = 2.10, 95% confidence interval [CI] = 1.56-2.84); it also displayed an independent prediction role for LVEF in heart failure cases of all etiologies (P = 0.002, OR = 4.05, 95% CI = 1.36-10.06). In subanalyses according to CHF etiology the LEPR Gln223Arg showed an independent prediction role for NYHA IV in IHD patients (P = 0.0001, OR = 2.50, 95% CI = 1.69-3.82) and both for NYHA IV(P = 0.007, OR = 2.04, 95% CI = 1.20-3.84) and LVEF (P = 0.004, OR = 11.87, 95% CI = 2.08-55.6) in DCMP patients. The role of the polymorphic variants in the genes encoding for adipokines as potential CHF susceptibility genes is unclear. Based on our findings, the LEPR Gln223Arg polymorphism could be considered a disease susceptibility modulating factor both in ischemic heart disease or dilated cardiomyopathy patients. © Springer Japan 2009.