Influence of genetic makers on response to a dietary intervention to reduce body weight

Abstract

Genetic and environmental factors are involved in the pathogenesis of the obesity and type 2 diabetes (DM2). Gene polymorphisms have been found to be related with variations in body weight reduction and control in response to caloric restriction. We have demonstrated association of variants in leptin, leptin receptor (LEPR) and PPARgamma with obesity and DM2. This project aims to investigate the influence of a dietary intervention for body weight reduction. One-hundred obese individuals (body mass index: BMI> 30 kg/m2) will be selected and oriented to follow a program of nutritional orientation (hypocaloric diet) during nine weeks. The assessment of the food intake will be carried out by a 24-hour dietary recall and data will be analyzed using the Brazilian Table of Food Composition of the USP. Anthropometric parameters and body composition will be measured before and after the nutritional intervention. Blood samples will be obtained for DNA extraction and laboratory testes to evaluate lipid and glucose metabolism, and obesity and inflammatory markers. Polymorphisms of the genes LEP (G-2458A e A19G), LEPR (Lys109Arg e Gln223Arg), FTO (rs9930506 e rs9939609), PPARG (Pro12Ala e C161T), ADIPOQ (45T>G e 276G>T) e IL6 (-174G>C) will be analyzed by allelic discrimination using real time PCR strategies to be confirmed by PCR-RFLP and DNA sequencing. The relationships between these polymorphisms and biochemical, inflammatory, anthropometric and body composition variables, as well as their influence on dietary intervention response will be evaluated. This study will contribute to the knowledge of the gene-diet interactions in obese individuals and it will aid the personalized nutritional orientation to achieve the goals of body weight reduction and reduce the cardiovascular risk of obese individuals. (AU)