大豆异黄酮对实验性糖尿病大鼠肝脏的保护作用及其机制研究

The Protective Effect and Mechanism of Soybean Isoflavone on Hepatic of Experimental Diabetic Rats

目的研究大豆异黄酮对实验性糖尿病大鼠肝脏的保护作用并探讨其作用机制。方法将120只清洁级SD大鼠随机分为正常对照组,糖尿病模型组,大豆异黄酮(40、80、160和320mg/kg)治疗组,每组20只。除正常对照组外,其余各组均通过一次性腹腔注射链脲佐菌素(STZ)制备大鼠糖尿病模型。8周后,分别测定各组大鼠体质量和肝脏指数;检测血清中谷氨酸氨基转移酶(ALT)、谷草氨酸氨基转移酶(AST)、碱性磷酸酶(ALP)活性和丙二醛(MDA)含量;分析测定肝脏组织中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)活性;通过苏木精-尹红(HE)染色观察肝脏组织病理形态学改变。结果与糖尿病模型组相比,大豆异黄酮(160和320 mg/kg)治疗组体质量显著增高且肝脏指数显著降低(P<0.05,P<0.01),血清中ALP活性明显降低(P<0.05,P<0.01),肝脏组织中GSH-Px活性显著升高(P<0.01,P<0.05);大豆异黄酮治疗组(80、160和320 mg/kg)血清中ALT、AST活性和MDA含量均显著降低(P<0.05,P<0.01),肝脏组织中SOD、CAT活性显著升高(P<0.05,P<0.01);大豆异黄酮治疗组肝脏组织病理形态学改变明显改善。其中以320 mg/kg治疗组疗效最为显著。结论大豆异黄酮对实验性糖尿病大鼠肝脏组织具有剂量依赖性的保护作用,其机制可能与其能够有效改善抗氧化酶系统的活性,降低氧化应激损伤有关。

Objective To investigate the protective effects of Soybean Isoflavone( SI) on hepatic of diabetic rats and its mechanism. Methods 120 rats were randomly divided into six groups: the normal control group,the diabetes model control group,the SI( 40,80,160 and 320 mg / kg) treatment groups,which has20 experimental rats in every group. Expect the normal control group,the experimental diabetes model were made by intraperitoneal injecting streptozocin( STZ). 8 weeks later,the body weight and hepatic index were detected; the content of ALT,AST,ALP and MDA in serum were determined; the activity of SOD,GSH-Px,CAT in hepatic tissue were also determined; and the histopathological changes of hepatic tissue was observed by HE staining. Results Compared with the diabetes model control group,the body weight and hepatic index of SI( 160 and 320 mg / kg) treatment groups were significantly different( P < 0. 05,P < 0. 01),the activity of ALP in serum was significantly decreased( P < 0. 05,P < 0. 01),and the activity of GSH-Px in hepatic tissue was significantly increased( P < 0. 01,P < 0. 05); the activity of ALT and AST,and the content of MDA of SI( 80,160 and 320 mg / kg) treatment groups was significantly decreased( P < 0. 05,P < 0. 01),and the activity of SOD and CAT in hepatic tissue was significantly decreased( P < 0. 05,P < 0. 01),and the hepatic tissue histopathological changes of SI treatment groups were significantly improved. Conclusion SI had dose-dependent hepatic protective effect in experimental diabetic rats,whose mechanism perhaps related to its effects of improving the activity of antioxidase and reducing oxidative stress injury.