Abstract
Background
The aim of this study was to investigate the effects of Roux-en-Y gastric bypass (RYGB) on glucose tolerance and insulin resistance in type 2 diabetic rats and the possible mechanisms involved in this process.
Methods
Thirty Goto-Kakizaki (GK) rats were randomly divided into three groups: RYGB operation, sham operation, and food restriction groups. Ten Wistar rats were used as non-diabetic control. The body weight and food consumption of rats were recorded 1 week before or every week after surgery. The fasting blood sugar and oral glucose tolerance test were performed using blood glucose meter. The levels of plasma insulin or glucagon-like peptide-1 (GLP-1) were evaluated by enzyme-linked immunosorbent assay. The insulin resistance was quantified using homeostasis model assessment method. The expression of GLP-1 receptor, Bcl-2, Bax, and caspase-3 was determined by Western blotting.
Results
Our results revealed that RYGB efficiently improved both glucose tolerance and insulin resistance in GK diabetic rats by upregulating GLP-1/GLP-1R expression. In addition, GLP-1R agonist exendin-4 dose-dependently increased insulin secretion in RIN-m5F cells and regulated the proliferation and apoptosis of these cells.
Conclusions
RYGB provides a valuable therapeutic option for patients with type 2 diabetes. GLP-1 may contribute to the regulation of pancreatic β-cell function through its receptor following RYGB.
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Liu, Y., Zhou, Y., Wang, Y. et al. Roux-en-Y Gastric Bypass-Induced Improvement of Glucose Tolerance and Insulin Resistance in Type 2 Diabetic Rats Are Mediated by Glucagon-Like Peptide-1. OBES SURG 21, 1424–1431 (2011). https://doi.org/10.1007/s11695-011-0388-z
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DOI: https://doi.org/10.1007/s11695-011-0388-z