Background: Polymorphisms in genes encoding adiponectin (ADIPOQ) and interleukin-6 (IL6) have been associated with adiposity and obese-related phenotypes. This study investigated the relationship of ADIPOQ and IL6 gene polymorphisms with pro-inflammatory and cardiometabolic markers in obese patients.
Methods: Anthropometric and body composition parameters were measured in 249 Brazilian subjects (30 to 68 yr). Metabolic and inflammatory markers and adipokines were analyzed in blood samples. ADIPOQ rs2241766 (45 T > G) and IL6 rs1800795 (-174G > C) polymorphisms were analyzed by real-time PCR and PCR-RFLP, respectively.
Results: Type 2 diabetes, hypertension, dyslipidemia and increased values of waist circumference, body fat, leptin, fibrinogen, IL-1β, hsCRP and TNFα were related to obesity (p < 0.05). Multiple linear regression analysis showed a positive correlation between BMI and waist circumference, body fat, leptin, fibrinogen, PAI-1, IL-1β, hsCRP and TNFα values (p < 0.001) but not with adiponectin. Obese group had altered metabolic status, resistance to leptin and insulin, and atherogenic and pro-inflammatory profiles. ADIPOQ and IL6 variants were not directely related to obesity, leptin resistance or alterations in cardiometabolic markers. Individuals carrying ADIPOQ 45G allele (TG + GG genotype) had higher IL-6, IL-1β and TNFα levels than TT genotype carriers (p < 0.05). IL6 -174GG genotype was associated with increased IL-1β levels (p = 0.033).
Conclusion: Obesity is associated with leptin resistance, cardiometabolic alterations and a pro-inflammatory status. Our results are suggestive that ADIPOQ and IL6 polymorphisms contribute to cardiometabolic risk in obese individuals.
Keywords: Adiponectin; Gene polymorphism; Inflammation; Interleukin-6; Obesity.