|Van Loan, Marta|
Submitted to: Trade Journal Publication
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/20/2006
Publication Date: 9/21/2006
Citation: Swarbrick, M.M., Austrheim-Smith, I., Stanhope, K., Van Loan, M.D., Ali, M., Wolfe, B., Havel, P.J. Circulating concentrations of high molecular weight adiponectin multimers increase following roux-en-y gastric bypass surgery. Diabetologcia 49:2552-2558.
Interpretive Summary: Obesity is a major health epidemic in the US and more individuals are turning to surgical procedures to help them lose weight. A common surgical technique is the Roux-en-Y gastric bypass. While post surgical patients have lost significant amounts of weight following gastric surgery the improvement seen for insulin sensitivity occurs before the patients experience large amounts of weight loss. Results from a recent study of obese patients that had gastric bypass surgery showed that the body’s ability to use the insulin sensitizing hormone adiponectin was enhanced long before a significant amount of weight was lost. Specifically, the hormone adiponectin has a high molecular weight portion. It was the high molecular weight portion of adiponectin that increased in blood early in the first month following surgery. By 12 months post surgery the levels of high molecular weight adiponectin were significantly greater than pre-surgery levels. These results suggest that the increased blood levels of the high molecular weight adiponectic may contribute to the rapid improvement in the body’s ability to use insulin, a hormone that regulates blood sugar levels. Improved blood sugar levels could result in an early reduction in type II diabetes in these obese patients.
Technical Abstract: In addition to weight loss, bariatric surgery for severe obesity has been reported to rapidly improve insulin sensitivity, often leading to a sustained resolution of type-2 diabetes mellitus 1. This effect has been proposed to result from the marked early restriction of food intake and/or increased secretion of incretin hormones 2. In this letter, we report for the first time that the proportion of the high molecular weight (HMW) component of circulating adiponectin, an adipocyte-derived hormone with insulin-sensitizing actions, is increased at one month following Roux-en-Y gastric bypass surgery. At 12 months after surgery, both total adiponectin concentrations and the HMW component were significantly increased relative to pre-operative levels. In addition, the increase of HMW adiponectin was correlated with the decrease of fasting insulin levels and with the improvement in insulin sensitivity 12 months following surgery. These data suggest that increased circulating levels of the HMW form of adiponectin could contribute to the rapid and sustained improvements of insulin sensitivity induced by this surgical procedure.