ARS | Publication request: Longitudinal changes of pancreatic and adipocyte hormones following Roux-en-Y gastric bypass surgery.

Submitted to: Diabetologia
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 14, 2008
Publication Date: August 15, 2008
Citation: Swarbrick, M.M., Austrheim-Smith, I.T., Stanhope, K.L., Van Loan, M.D., Ali, M.R., Wolfe, B.M., Havel, P.J. 2008. Longitudinal changes of pancreatic and adipocyte hormones following Roux-en-Y gastric bypass surgery.. Diabetologia.51:1901-1911.

Interpretive Summary: Obesity is a major public health issue for Americans. Medical costs associated with obesity related diseases and illnesses are in the billions annually. Research into treatment approaches that reduce the degree of obesity can save significant medical costs associated with diabetes, hypertension, and heart disease. Bariatric surgery which reduces the stomach’s capacity for food, is becoming a common treatment modality and, therefore, requires investigations into its benefits and risks. We conducted a comprehensive, longitudinal investigation of hormone changes following gastric bypass surgery. Nineteen severely obese women were examined prior to surgery and at 1, 3, 6, and 12 months after surgery. Before surgery we found that the amount of body fat was related to elevated levels of several hormones and markers of inflammation. After surgery and weight loss all hormones and inflammation markers were significantly decreased by 12 months. These changes as well as improvements in blood sugar suggest that gastric bypass surgery may be successful in treating markers of disease in obese individuals.

Technical Abstract: The use of bariatric surgery for the treatment of severe obesity is increasing, because in addition to dramatic weight loss, co-morbidities such as type 2 diabetes (T2DM) are frequently resolved. The mechanisms by which this occurs have not been fully elucidated, but are likely to involve changes of hormones produced by the gastrointestinal tract, pancreas and adipose tissue. Our objective was to conduct a comprehensive, longitudinal investigation of endocrine changes following Roux-en-Y gastric bypass surgery (RYGBP), focusing on pancreatic and adipocyte hormones and systemic markers of inflammation. Subjects and Methods: Nineteen severely obese women (BMI 45.6±1.6 kg/m2) were studied prior to, and at 1, 3, 6, and 12 months after RYGBP. Body composition was assessed before surgery and at 1 and 12 months. Results: Before RYGBP, adiposity was positively correlated with circulating leptin, visfatin, IL-6, hsCRP and MCP-1 concentrations. RYGBP reduced fasting insulin and glucose concentrations, as well as glucagon and pancreatic polypeptide (PP). With the exception of retinol-binding protein-4 and adiponectin, concentrations of the adipocyte hormones studied (leptin, acylation-stimulating protein and visfatin) and markers of inflammation (IL-6, hsCRP and sICAM-1) decreased significantly in the 12 months following RYGBP. In multivariate analyses, decreases of fat mass and body weight after RYGBP were predicted by changes of leptin and HMW adiponectin concentrations. Improvements of insulin sensitivity (HOMA-IR) were independently predicted by changes of glucagon, PP, and visfatin. Conclusions: These results suggest a role for pancreatic and adipocyte hormones in the resolution of insulin resistance/T2DM following RYGBP in severely obese subjects.