Influence of duodenal-jejunal bypass surgery on intestinal hormone and hepatic endoplasmic reticulum stress in diabetic rats

Abstract

Objective To establish the diabetic rat model, to perform the duodenal-jejunal bypass surgery (DJB), and to observe the influence of DJB on intestinal hormone and hepatic endoplasmic reticulum stress in diabetic rats. Methods A total of 58 SD adult male rats induced by a high-fat diet feeding and intraperitoneal injection of low-dose streptozotocin to establish the diabetic rat model. Afterwards, DJB (DJB group) and sham surgery (sham surgery group) were conducted in the diabetic rats. The normal rats were taken as the blank control (blank control group). The intestinal hormone and insulin of three groups were detected. The changes of postoperative hepatic endoplasmic reticulum stress indexes [p-double stranded RNA-dependent protein kinase-like ER kinase (p-PERK), inositol requiring enzyme-1 (IRE-1), p-IRE-1], hepatic tissues [total c-Jun NH2-terminal kinase (JNK), p-JNK protein], insulin receptor substrate-1 (IRS-1) protein, p-IRS-1ser307 protein expression in hepatic tissues of two groups were observed. Results Before gastric perfusion, there was no statistical difference in the levels of glucagon-like peptide-1 (GLP-1), GIP, INS among the rats of three groups (F=0.04, 2.708, 0.002, P=0.996, 0.079, 0.998); After gastric perfusion for 30 min, the levels of GLP-1, GIP, INS in DJB group and control group were higher than those in sham surgery group (F=33.692, 18.657, 16.393, P=0.000); After surgery for 16 weeks, the p-PERK, p-IRE-1, p-JNK, p-IRS-1ser307 in DJB group were compared with those before surgery, and there was statistical difference (t=10.507, 12.606, 9.163, 14.603, P=0.000); The IRE-1, JNK, IRS-1 were compared with those before surgery, and there was no statistical difference (t=1.295, 1.863, 1.675, P=0.205, 0.072, 0.104); DJB group improved better than sham surgery group. Conclusion DJB for diabetic rats induced by high-fat diet feeding combined with intraperitoneal injection of low-dose streptozotocin can effectively improve intestinal hormone and insulin, relieve endoplasmic reticulum stress. Key words: Diabetes; Duodenal-jejunal bypass surgery; Intestinal hormone of rats; Hepatic endoplasmic reticulum stress