The most frequently used, and effective, treatment for morbid obesity is Roux-en-Y gastric bypass surgery (RYGB), which results in rapid remission of T2D in most cases. To what extent this is accounted for by weight loss or other factors remains elusive. To gain insight into these mechanisms, we investigated the effects of RYGB on ß-cell function and ß-cell mass in the pig, a species highly reminiscent of the human. RYGB was performed using linear staplers during open surgery. Sham-operated pigs were used as controls. Both groups were fed a low calorie diet for 3 weeks after surgery. Intravenous glucose-tolerance tests were performed 2 weeks after surgery. Body weight in RYGB-pigs and sham-operated, pair-fed control pigs developed similarly. RYGB-pigs displayed improved glycaemic control, which was attributed to increases in ß-cell mass, islet number and number of extra-islet ß-cells. Pancreatic expression of insulin and glucagon was elevated, and cells expressing the GLP-1-receptor were more abundant in RYGB-pigs. Our data from a pig model of RYGB emphasize the key role of improved ß-cell function and ß-cell mass to explain the improved glucose tolerance after RYGB as food intake and body weight remained identical.
- Received June 25, 2013.
- Accepted January 17, 2014.
- © 2014 by the American Diabetes Association.
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