玉米须对2型糖尿病模型大鼠降糖机制研究

Mechanism of corn stigma against rat model of type 2 diabetes mellitus

目的:研究玉米须对2型糖尿病模型大鼠脂肪组织富含半胱氨酸的酸性分泌蛋白(SPARC)的调控及胰腺病理结构的影响,探讨其作用机制。方法:采用高脂饲料结合小剂量链脲佐菌素建立2型糖尿病大鼠模型,灌胃给予玉米须提取物4周,摘取胰腺用于病理组织观察,并采用RT-PCR和Western blot方法检测脂肪组织SPARC m RNA和蛋白表达水平。结果:与模型组比较,给药组脂肪组织SPARC m RNA和蛋白表达水平明显下调(P<0.05),且对受损胰岛有修复作用,能够减少胰腺脂肪异位沉积。结论:玉米须降血糖的作用机制可能与其抑制脂肪组织SPARC的表达及减少脂肪异位沉积有关。

Objective： To study the effect and mechanism of corn stigma extract on regulating the expression of SPARC in adipose tissue and pathological changes of pancreas in rat model of type 2 diabetes mellitus（T2DM）. Methods： T2 DM model rats were established by using high-fat diet combined with a small dose injection of streptozotocin（STZ）. The rats were administrated with the treatment of corn stigma extract by gavage for 4 weeks. Pancreas was harvested to observe pathological changes, and the expression of SPARC m RNA and protein in adipose tissue were detected by RT-PCR and Western-blot, resepectively. Results： Compared with the model group, the expression of SPARC m RNA and protein in adipose tissue were obviously decreased by the treatment of corn stigma extract. Treatment of corn stigma could repair impaired pancreas islet and reduce ectopic fat deposition in pancreas. Conclusion： The potential mechanism of corn stigma against T2 DM is partly related to inhibit the expression of SPARC in adipose tissue and reduce ectopic fat deposition.