ASSESSING OBESITY AND INSULIN MOLECULAR PATHWAYS INVOLVED IN WEIGHT LOSS INDUCED BY ROUX-EN-Y GASTRIC BYPASS

Introduction:  Given the role genetics plays in weight regulation, the magnitude of weight loss after Roux-en-Y gastric bypass (RYGB) can also be genetically determined. The present study aimed to evaluate how the expression of genes involved in insulin metabolism and obesity pathways changed after RYGB. Materials and Methods:  Blood samples were obtained from 13 women (35.9±9.2 years) with severe obesity before and six months after RYGB. Whole blood transcriptome was assayed by microarray. Results:  A total of 1966 up- or downregulated genes were identified in pre- and postoperative periods of bariatric surgery. From these analyses, we observed that genes involved in obesity and in insulin pathways were upregulated after RYGB, especially the genes IKBKB, PIK3R1, and PLA2G4A (p<0.05). Conclusion:  Microarray is a powerful tool for identifying biomarkers in obese patients in the pre- and postoperative periods of RYGB by analyzing differential gene expression profiles. Our findings in blood support previous studies documented in adipose tissue. RYGB promotes upregulation of genes involved in obesity and insulin pathways, which is associated with improved glucose metabolism. Inflammation due to acute weight loss and surgical procedure per se may explain the upregulation of IKKB. Based on our findings in blood, it may be possible to promote the development of therapeutic targets for specific altered genes. Acknowledgements :  Sao Paulo Research Foundation (FAPESP) (#grant No. 2013/12819-4) and National Council for Scientific and Technological Development (CNPq) (#grant No. 480763/2013-5)