中药黄芪多糖对糖尿病大鼠心肌GLUT4表达的影响

目的:探讨黄芪多糖(APS)对糖尿病大鼠的治疗作用以及对心肌组织葡萄糖转运蛋白(GLUT)4表达的影响。方法:Wistar大鼠40只,雄性,随机分为4组,每组10只:正常对照组、糖尿病组(高热量饮食+小剂量链脲佐霉素35mg·kg-1,尾静脉注射)、APS组(正常对照组+APS)和APS+糖尿病组(APS400mg·kg-1·d-1,溶液灌胃)。给药5周后观察动物一般情况,检测血糖和血清胰岛素水平,取心脏包埋制片用免疫荧光法检测GLUT4表达。结果:糖尿病组动物血糖水平及体重显著高于其他3组(P<0.01),APS+糖尿病组血糖水平高于正常对照组(P<0.01),血清胰岛素水平变化无统计学差异(P>0.05),心肌GLUT4表达量明显低于其他各组(P<0.01);APS组血糖,体重及血清胰岛素水平与正常对照组间均无统计学差异(P>0.05)。结论:APS具有降低糖尿病大鼠血糖和改善心肌胰岛素抵抗的作用,其机理可能与增强心肌组织中GLUT4的表达有关。

Effect of Astragalus Polysaccharide on Glucose Transporter 4 Expression in Cardiac Tissue of Type 2 Diabetic Rats

Objective: To investigate the effect of Astragalus polysaccharide(APS) treatment on type 2 diabetes mellitus (T2DM) rats and the GLUT4 expression in myocardium. Methods: 40 Wistar (male) rats were randomly divided into 4 groups :the control group,T2DM group (high-heat diet +35 mg·kg~(-1), a low dose of streptozotocin by end intravenous injection), APS group (control +APS )and APS+T2DM group(APS 400 mg·kg~(-1)·d~(-1) by irritating the stomach with the solution).After treatment for 5 weeks, the levels of serum glucose and insulin were assayed, and the expression of GLUT4 protein was assessed by immune fluorescence. Results: The levels of glucose and body weight in T2DM group were increased (P<0.01) and the levels of the GLUT4 expression in their cardiac tissues were lowered (P<0.01) while the change of serum insulin levels had no statistics difference (P>0.05) compared with the others respectively. The levels of glucose in APS+T2DM group were higher than those of the control group. Each index between APS and control group has no statistics difference(P>0.05). Conclusion: APS can reduce the levels of glucose in T2DM rats and improve the insulin resistance of cardiac tissue, and this protective mechanism may be relative to the enhanced GLUT4 expression in type 2 diabetic myocardium.