The association of SNP276G>T at adiponectin gene with insulin resistance and circulating adiponectin in response to two different hypocaloric diets.

BACKGROUND: Several adiponectin gene (ADIPOQ) single nucleotide polymorphisms (SNPS) have been related with adiponectin levels and risk for obesity.

OBJECTIVE: The aim of our study was to analyze the effect of rs1501299 ADIPOQ gene polymorphism and dietary intake on total adiponectin levels and insulin resistance after two hypocaloric diets in obese subjects.

MATERIAL AND METHODS: A Caucasian population of 284 obese patients was enrolled in a randomized clinical trial with two hypocaloric diets (I: moderate carbohydrates vs II: low fat). Before and after 12 weeks on each hypocaloric diet, an anthropometric evaluation, an assessment of nutritional intake and a biochemical analysis were realized. The statistical analysis was performed for the combined GT and TT as a group (mutant) and GG as second group (wild) (dominant model).

RESULTS: The genotype distribution was 149 GG, 124 GT and 21 TT. With caloric restriction strategies, body weight, body mass index (BMI), fat mass, waist circumference, systolic blood pressure, total LDL cholesterol, LDL cholesterol and leptin levels decreased. Only in subjects with GG genotype, diet I and II decreased fasting insulin levels, HOMA-IR and adiponectin levels. The improvement was similar with both diets; insulin concentrations (Diet I: -4.7 ± 1.4 mUI/L vs. Diet II: -5.9 ± 1.9 mUI/L: p = .76), HOMA-IR (Diet I: -1.4 ± 0.6 units vs. Diet II: -2.0 ± 0.7 units: p = .56) and adiponectin levels (Diet I: -10.2 ± 3.4 ng/dl vs. Diet II: -14.0 ± 2.9 ng/dl: p = .33).

CONCLUSION: The GG genotype of ADIPOQ gene variant (rs1501299) is associated with an increase in adiponectin levels and a decrease of insulin and HOMA-IR after weight loss.