滇结香花对他克莫司诱导的糖尿病大鼠胰腺的保护作用及机制研究

Protective Effect of Edgeworthia Gardneri Flos on Pancreas in Diabetes Mellitus Model Rats Induced by Tacrolimus and Its Mechanism

关键词:  他克莫司  糖尿病  滇结香花  保护胰腺  胰岛素受体底物蛋白2

Key words:  tacrolimus  diabetes mellitus  Edgeworthia gardneri Flos  protection of pancreas  insulin receptor substrate 2

摘要:

目的 研究滇结香花乙酸乙酯提取物（ethyl acetate extraction from Edgeworthia gardneri Flos，EG）对他克莫司诱导的糖尿病模型大鼠胰腺的保护作用及其机制。方法 将40只SD大鼠随机分为正常组、模型组、滇结香花组和罗格列酮组，每组10只。采用他克莫司单因素干预制作SD大鼠糖尿病模型，通过检测大鼠空腹血糖、胰岛素、糖化血红蛋白水平，显微镜下观察胰腺组织病理学变化，评价EG降糖和保护胰腺组织的作用。并采用RT-PCR和Western blot分别检测胰腺组织中胰岛素受体底物蛋白2（insulin receptor substrate 2，IRS-2）mRNA和蛋白表达水平，探究EG保护糖尿病胰腺组织的作用机制。结果 与正常组比较，他克莫司诱导的糖尿病模型大鼠血糖、胰岛素抵抗指数、糖化血红蛋白升高，胰岛素、胰岛素分泌指数降低（P<0.05）。与模型组比较，滇结香花组血糖、糖化血红蛋白降低，胰岛素、胰岛素分泌指数升高（P<0.05），大鼠胰腺组织IRS-2 mRNA表达量和IRS-2蛋白表达量增加（P<0.05）。HE染色观察到滇结香花组大鼠胰腺组织切片中胰岛细胞形态结构明显改善，细胞数目增多，排列较整齐，胞浆分布均匀。结论 EG能降低他克莫司诱导的糖尿病模型大鼠的血糖、糖化血红蛋白水平，其机制可能是通过胰腺胰岛素信号转导通路中胰岛素受体底物，保护胰腺，促进胰岛素分泌，增强糖代谢。

Abstract:

OBJECTIVE To research the protection effect of ethyl acetate extraction from Edgeworthia gardneri Flos(EG) on pancreas in diabetes mellitus model rats induced by tacrolimus and its mechanism. METHODS Forty SD rats were randomly divided into normal group, model group, Edgeworthia gardneri Flos group and rosiglitazone group, with 10 rats in each group. Diabetes mellitus model was established by tacrolimus intraperitoneal injection. The levels of blood glucose, insuline and HbAlc were detected. The pancreas was observed by optical microscopy and HE staining techniques. The mRNA and protein expression of pancreatic insulin receptor substrate 2(IRS-2) were detected by RT-PCR and Western blot. RESULTS The level of blood glucose, HOMA-IR, HbAlc of model group increased compared with the normal group, while the insulin and HOMA-β decreased(P<0.05). The blood glucose, HbAlc of Edgeworthia gardneri Flos group decreased compared with the model group, and the insulin and HOMA-β increased(P<0.05), IRS-2 mRNA and IRS-2 protein increased(P<0.05). HE staining pictures showed that the morphology and structure of pancreatic cells in Edgeworthia gardneri Flos group were significantly improved. The number of pancreatic cells increased, arranging neatly. And the cytoplasm was evenly distributed. CONCLUSION EG can reduce blood glucose and HbAlc formation. The mechanism may be through the insulin signal pathway in pancreas to protect β cells, increase insulin secretion, enhance glucose metabolism.