2型糖尿病大鼠肝脏IRS-1的变化及丝胶的调节作用

CHANGES OF IRS-1 IN THE LIVER OF TYPE 2 DIABETIC RATS AND THE REGULATORY ROLES OF SERICIN

目的:研究2型糖尿病大鼠肝脏胰岛素受体底物-1(IRS-1)表达的变化及丝胶的调节作用。方法:将36只雄性SPF级SD大鼠随机分为正常组(12只)和造模组(24只),造模组大鼠采用腹腔注射链脲佐菌素+高脂高糖饲料饲养的方法建立2型糖尿病大鼠模型,成模后将大鼠随机分为模型组(12只)和实验组(12只)。连续给予实验组大鼠丝胶、其余组大鼠生理盐水灌胃35d。葡萄糖氧化酶法用于检测各组大鼠空腹血糖;SP免疫组织化学法、Real Time Q-PCR法用于检测各组大鼠肝脏IRS-1的表达。结果:同模型组大鼠相比,实验组大鼠血糖明显降低、IRS-1的表达明显升高(P<0.05)。结论:丝胶降低血糖的作用可能是通过上调肝脏IRS-1的表达进而增强胰岛素信号通路的转导效应来实现。

Objective:To investigate changes of insulin receptor substrate-1(IRS-1)in the liver of type 2 diabetic rats and the regulatory role of sericin.Methods:Thirty-six specific pathogen free(SPF)male rats were randomly divided into normal group(12 rats)and modeling group(24 rats).The rat’s model of type 2 diabetes mellitus was induced by high-fat,high-sugar feeding and intraperitoneal injection of streptozotocin.After modeling,the rats were randomly divided into model group(12 rats)and experimental group(12 rats).The rats in experimental group were given sericin for 35 days and other rats were given equal volume normal saline for 35 days.The glucose oxidase method was used to detect the fasting blood glucose of rats in each group.SP immunohistochemical staining and Real Time Q-PCR were used to detect the expression of IRS-1 in liver.Results:Compared with the rats in the model group,the blood glucose of rats in experimental group reduced significantly,and the expression of liver IRS-1 of rats in experimental group increased significantly(P<0.05).Conclusions:Sericin can enhance the effects of insulin signaling by upregulating the expression of IRS-1 in liver of diabetes mellitus rats,thus reducing the blood glucose.