小檗碱对2型糖尿病大鼠胰岛细胞InsR与IRS-1／-2蛋白表达的影响

目的：从胰岛细胞胰岛素信号转导通路探讨小檗碱治疗2型糖尿病的作用机制。方法：以小剂量链脲佐菌素腹腔注射（28mg／kg）加高脂饮食诱导2型糖尿病大鼠模型，成模后给予小檗碱治疗8周。检测大鼠空腹血糖以及胰岛细胞胰岛素（Ins）、胰高血糖素（Glc）、胰岛素受体（InsR）、胰岛素受体底物1和底物2（IRS-1／-2）的蛋白表达。结果：小檗碱治疗8周，能显著降低模型大鼠的空腹血糖和胰岛Glc蛋白表达，同时能显著升高胰岛细胞InsR、IRS-1的蛋白表达。结论：小檗碱调节血糖的作用可能与其提高胰岛细胞InsR、IRS-1蛋白表达从而改善胰岛细胞的胰岛素信号转导有关。

Effects of Berberine on Protein Expression of InsR, IRS-1/-2 of Islet Cell in Rats with Type 2 Diabetes Mellitus

Objective： To investigate the mechanism of berberine in treating type 2 diabetes mellitus （T2DM） by analyzing insulin signal pathway of islet cell. Methods： The model of T2DM rat was induced by intraperitoneal injection of streptozotocin （28mg/kg） and high-fat diet. T2DM rats were administered with berberine for 8 weeks after the model was established. Fasting blood glucose （FBG） and protein expression of insulin （Ins）, glucagons （Gle）, insulin receptor （InsR）, insulin receptor substance 1 and 2 （IRS-1/-2） in islet ceils were detected. Results： After treatment with berberine for 8 weeks, the FBG and protein expression of Glc in diabetic rats decreased and the protein expression of InsR and IRS-1 in islet cells increased significantly. Conclusion ： The effects of berberine on blood glucose may have connection with raising the InsR and IRS-1 protein expression in islet cell to improve insulin signal transduction.