Getting By(pass) with Help from Our Little Friends
One of the most durably effective treatments for severe obesity is gastric bypass surgery. Despite its powerful effect on weight loss and remission of diabetes, the cost and associated risk of this procedure prevents its application to a large population of obese patients, prompting a search for less invasive treatments. The population structure of the trillions of microorganisms that reside in the human gut is markedly altered after gastric bypass, but the functional importance of these changes is unknown. In a new study, Liou et al. use a mouse model of gastric bypass surgery to characterize changes in the gut microbiota, both temporally and along the length of the gastrointestinal tract. Gastric bypass induced substantial, rapid, and sustained changes to the gut microbial communities that were independent of both diet and the weight loss associated with this procedure. The observed changes in this mouse model were similar to those previously observed in human gastric bypass patients. Transfer of the surgically altered microbial community to nonoperated, germ-free mice resulted in weight loss and decreased body fat. Gastric bypass was also associated with changes in the production of short-chain fatty acids, changes that were conveyed to the previously germ-free mice that received the microbiota from these operated animals. These observations demonstrate that specific alterations in the gut microbiota contribute to the beneficial effects of bariatric surgery on energy balance and obesity. They suggest new approaches to the treatment of obesity and related metabolic diseases that harness the ability of the gut microbiota to influence host metabolic physiology.
- Copyright © 2013, American Association for the Advancement of Science
