基于PI3K、Akt信号通路探讨山腊梅叶乙醇提取物的降糖降脂作用

Study on the Hypoglycemic and Lipid-lowering Effects of the Ethanol Extracts from the Leaves of Chimonanthus Sibiricus Based on PI3K and Akt Signal Pathways

目的观察分析山腊梅叶乙醇提取物对高脂高糖糖尿病大鼠的降糖降脂调控作用。方法将大鼠随机分为5组:正常对照组、模型组、山腊梅叶提取物低剂量组、山腊梅叶提取物高剂量组(下文简称低、高剂量组)及二甲双胍组,每组15只,除正常组大鼠外,其余大鼠采用高脂高糖饲料喂养+腹腔注射小剂量链脲佐菌素建立2型糖尿病模型。给药结束后测定各组大鼠血糖和血脂相关指标,并检测胰岛素受体底物(IRS)、磷脂酰肌醇-3激酶(PI3K)、蛋白激酶B(AKT)、葡萄糖转运体4(GLUT-4)表达水平。结果与正常对照组比较,模型组大鼠血清胰岛素水平下降,而空腹血糖、糖化血红蛋白,以及血清胆固醇(TC),三酰甘油(TG)及低密脂蛋白胆固醇(LDL-C)水平均明显升高,差异有统计学意义(P<0.05);与模型组比较,低剂量、高剂量组及二甲双胍组大鼠空腹血糖、糖化血红蛋白、血清TC、TG及LDL-C水平均明显降低,差异有统计学意义(P<0.05),血清胰岛素、肝脏IRS、PI3K、AKT、GLUT-4蛋白表达明显升高,差异有统计学意义(P<0.05)。结论山腊梅叶具有降低血糖、血脂之效,其机制可能与调节IRS-1、PI3K、Akt信号通路有关。

Objective To observe and analyze the regulating effect of the ethanol extract of Lasholm sibiricum leaves on the hypoglycemic and lipid-lowering regulation of high-fat and high-sugar diabetic rats.Methods The rats were randomly divided into five groups:the normal control group,the model group,the low-dose group of chimonanthus leaf extract,high-dose groups(of chimonanthus leaf extract low and high-dose groups)and the metformin group with 15 rats in each group.Except for the rats in the group,the other rats were fed with high-fat and high-sugar feed+intraperitoneal injection of small dose of streptozotocin to establish a type 2 diabetes model.After the administration,the blood glucose and blood lipid related indexes of each group of rats were measured,and the insulin receptor substrate(IRS),phosphatidylinositol-3 kinase(PI3K),protein kinase B(AKT),and glucose transporter 4(GLUT-4)expression level were measured.Results Compared with the normal control group,the serum insulin level of the model group decreased,while the fasting blood glucose,glycosylated hemoglobin,and serum TC,TG and LDL-C levels were significantly increased,the difference was statistically significant(P<0.05);compared with the model group,the fasting blood glucose,glycosylated hemoglobin,serum TC,TG and LDL-C levels of rats in the the low dose,high-dose group and metformin group were significantly reduced,the difference was statistically significant(P<0.05),and the protein expression of serum insulin,liver IRS,PI3K,AKT and GLUT-4 was significantly increased,the difference was statistically significant(P<0.05).Conclusion Serratia vulgaris leaves have the effect of lowering blood glucose and blood lipids,and its mechanism may be related to the regulation of IRS-1,PI3K,Akt signaling pathway.