黄芪多糖对2型糖尿病大鼠肝脏CHOP表达的影响

Effect of Astragalus Polysaccharide (APS) on CHOP Expression in the Hepatic Tissue of Type 2 Diabetic Rats

目的:探讨黄芪多糖(APS)对2型糖尿病(T2DM)大鼠肝脏内质网应激标志蛋白CHOP表达的影响。方法:雄性SPF级SD大鼠44只,随机分为:空白对照组(C组)、单纯APS灌胃对照组(CA组)、T2DM模型组(T2DM组)、T2DM+APS治疗组(T2DM+APS组)。定期监测各组动物体重(BW)、随机血糖(随机BG)、空腹血糖(FBG)、空腹胰岛素(Fins)水平、口服葡萄糖耐量试验(OGTT),计算胰岛素抵抗指数(HO-MA-IR);用Westernblot法检测各组动物肝组织CHOP的表达水平。结果:T2DM组大鼠BW、随机BG、FBG、Fins、HOMA-IR均显著高于C组,同时伴OGTT异常(P<0.01);T2DM+APS组大鼠BW、随机BG、FBG、HOMA-IR较T2DM组显著下降(P<0.01),OGTT各时点BG较T2DM组均显著降低(P<0.01);肝组织CHOP表达水平在T2DM组显著高于C组(P<0.01),T2DM+APS组表达水平明显低于T2DM组(P<0.05)。C组和CA组比较各项指标无显著性差异。结论:APS可显著降低T2DM大鼠血糖和改善胰岛素抵抗,其机制可能与APS减弱T2DM大鼠肝组织内质网应激蛋白CHOP表达有关。

Objective:To investigate the effects of astragalus polysaccharide(APS)on hepatic expression of CHOP,a kind of ER stress indicative protein,in type 2 diabetic rats.Method:44 SD male rats were randomly divided into four groups:the control group(group C),the control+APS group(group CA),the T2DM group(group T2DM),the T2DM+APS group(group T2DM+APS).Body weight,random and fast blood glucose,fast blood insulin level,oral glucose tolerance test and HOMA-IR index were observed pre-and post-APS therapy.The expression of CHOP was detected by western blot.Results:Compared with group C,there were significanly high in BW,RandomBG,FBG,Fins and HOMA-IR,and markedly impaired in OGTT in group T2DM(P<0.01);the BW,RandomBG,FBG and HOMA-IR of group T2DM+APS were markedly lower than those of group T2DM,the indexes for each time point of OGTT were lower than those of group T2DM(P<0.01);the expression level of CHOP in group T2DM was significantly higher than that of group C,but the expression level of CHOP in group T2DM+APS was markedly lower than that of group T2DM.There was no significant difference between group C and group CA.Conclusion:APS can reduce the levels of glucose in T2DM rats and improve the insulin resistance,and the mechanisms of its effects may be relative to the relievement of ER stress through reducing the expression of CHOP in T2DM rats.