A515 - Changes in gene expression modify the resting metabolic rate in women after bariatric surgery

Abstract

Background: Analysis of gene expression related to energy metabolism and subsequent association with the resting metabolic rate (RMR) may elucidate the understanding of genetic factors that contribute to obesity. The aim of this study was to analyze the expression of genes related to energy metabolism and associate it with the RMR in women with obesity before and after bariatric surgery. The sample consisted of 13 women before and after six months of bariatric surgery. The nutritional status was performed using Body Mass Index (BMI). The RMR was determined by the measurement of the oxygen consumed (O2) and carbon dioxide produced (CO2) using the QUARK-RMR equipment. The gene expression analysis was performed in peripheral blood by microarray methodology, BeadChip- Illumina™ and with subsequent validation by the quantitative Real Time PCR method. Data were analyzed by SPSS (p<0.05). Differences were observed in weight (115.3±19.4 vs 85.3±13.8kg, p<0.01), BMI (42.5±7.0 vs 31.8±5.4 kg/m2, p<0.01) and RMR (2.052±267 vs 1.743±154 kcal, p<0.01) after six months of bariatric surgery. There was an increasement in the gene expression of six targets related to energy metabolism after bariatric surgery, genes/fold change respectively, (CTNNB1/5.42, LEP/2.96, PPP2CB/3.35, RAP1B/5.51, GNB4/2.96, MLX/2.19).The association of genes with the RMR after bariatric surgery, was confirmed by multiple regression analysis (r2:0.971; p=0.02; CI:901;1655). There was significant weight loss, decreasement of BMI and increasement in the expression of genes related to energy metabolism after of surgical treatment. Understanding this pathway related to energy metabolism, can lead us to develop in the future new treatments for obesity.