Roux-en-Y gastric bypass increases hepatic and peripheral insulin sensitivity in rats with type 2 diabetes mellitus / 中国实验动物学报

ABSTRACT

Objective To investigate the effects of Roux-en-Y gastric bypass (RYGB) on hepatic and peripheral insulin sensitivity in rats with type 2 diabetes and their possible mechanisms.Methods 5-6 week old SPF male Sprague-Dawley rats were divided into 2 groups diabetic RYGB group (n=21) and diabetic RYGB sham group (n=7).The hyperinsulinemic-euglycemic clamp with tracer infusion was completed at 2,4,and 8 weeks postoperatively to assess the insulin sensitivity.The lipid content in liver and muscle tissue was examined.Results Postoperatively,the diabetic RYGB group had significant decreases in weight,fat mass,and RYGB had a profound effect on the plasma lipid profile.Two weeks after surgery,the hepatic insulin sensitivity index was significantly improved and the hepatic triglyceride was decreased in the RYGB group (P<0.05).The significant increased insulin sensitivity was not detected until four weeks after RYGB surgery,the M value was significantly increased and the TG content in the muscle tissue was significantly decreased (P<0.05).Conclusions The increased insulin sensitivity after RYGB occurs earlier in the liver than in the muscle and both may contribute to the long-term remission of type 2 diabetes.Reduced lipid content in hepatocytes and skeletal muscle cells after RYGB may contribute to the improved insulin sensitivity in these cells.