Gastric Bypass Increases Intestinal Glucose Production
Is more effective than gastric lap-banding in mice
FRIDAY, Sept. 5 (HealthDay News) -- A version of gastric bypass surgery in mice is more effective than gastric lap-banding surgery at reducing food intake and increasing insulin sensitivity due to increased intestinal production of glucose, according to study findings published in the Sept. 3 issue of Cell Metabolism.
Stephanie Troy, from University Paris 7 in Paris, France, and colleagues performed gastric lap-band surgery, placing a band on the upper part of the stomach, and enterogastro anastomosis (EGA) surgery (to approximate Roux-en-Y gastric bypass surgery, which involves excising a large part of the stomach and connecting it to the intestine, which cannot be done in mice), on 6-month-old male mice fed a high-fat diet. The authors note that Roux-en-Y surgery in humans leads to a rapid and substantial control of type 2 diabetes, often within days, which is not observed with adjustable gastric banding.
The researchers found that EGA reduced food intake and increased insulin sensitivity more effectively than gastric lap-banding, and unlike gastric lap-banding, increased intestinal gluconeogenesis. These effects were not observed in mice lacking the glucose transporter GLUT-2, which is necessary for hepatoportal glucose sensing, or in mice locally treated with a drug to denervate the portal vein.
"In conclusion, our study provides new findings about the mechanisms by which the gastric bypass rapidly improves glucose homeostasis," Troy and colleagues write. "This leads us to propose that intestine glucose metabolism, especially through its gluconeogenic function, may be a crucial actor not only in the control of food intake but also for the regulation of glucose homeostasis."