基于SIRT1/UCP2信号通路观察二陈汤对2型糖尿病合并非酒精性脂肪性肝病大鼠的影响

Effect of Erchen Decoction on Rat Model with Type 2 Diabetes Mellitus and Nonalcoholic Fatty Liver Based on the SIRT1/UCP2 Signaling Pathway

关键词:  二陈汤|2型糖尿病|非酒精性脂肪肝|糖脂代谢|氧化应激|沉默调节蛋白1|线粒体偶连蛋白2

Key words:  Erchen decoction|type 2 diabetes mellitus|nonalcoholic fatty liver|glycolipid metabolism|oxidative stress|SIRT1|UCP2

摘要:

目的 探讨二陈汤对2型糖尿病（type 2 diabetes mellitus，T2DM）合并非酒精性脂肪性肝病（nonalcoholic fatty liver disease，NAFLD）大鼠糖脂代谢及氧化应激的作用，并探讨其可能作用机制。方法 40只♂ SD大鼠随机选取10只为正常对照组，其余大鼠造模成功后，随机选取20只分为模型组和二陈汤组，每组10只。正常对照组给予常规饲料喂养，模型组结合高脂高糖饲料喂养及单次腹腔注射链脲佐菌素30 mg·kg^-1以制备T2DM合并NAFLD大鼠模型，二陈汤组灌胃给予二陈汤（每天1.0 g·mL^-1生药量）。12周后检测各组大鼠生化指标、氧化应激指标；HE染色法观察肝脏组织病理变化；免疫组化法、q-PCR及Western blotting检测肝脏组织SIRT1/UCP2信号通路的表达。结果 与模型组比，二陈汤显著改善T2DM合并NAFLD大鼠体质量及代谢功能，降低空腹血糖、谷丙转氨酶、天门冬氨酸氨基转移酶、甘油三酯、总胆固醇、低密度脂蛋白胆固醇、极低密度脂蛋白、游离脂肪酸、空腹胰岛素、胰岛素抵抗指数、丙二醛水平，且高密度脂蛋白、超氧化物歧化酶、谷胱甘肽过氧化物酶、过氧化氢酶均明显升高。HE染色结果显示，模型组肝组织出现重度的脂肪变性，二陈汤显著减轻肝细胞脂肪性变。免疫组化、q-PCR与Western blotting结果显示，与模型组比较，二陈汤组SIRT1 mRNA和蛋白的表达显著上调，UCP2 mRNA与蛋白的表达显著降低。结论 二陈汤在一定程度上对T2DM合并NAFLD大鼠具有改善作用，其机制可能与调节SIRT1/UCP2信号通路有关。

Abstract:

OBJECTIVE To explore the effects and potential mechanisms of Erchen decoction on the glycolipid metabolism and oxidative stress in type 2 diabetes mellitus(T2DM) rats with nonalcoholic fatty liver desease(NAFLD). METHODS Forty ♂ SD rats were randomly selected as the normal control group, and 10 rats were randomly selected as the normal control group. After the other rats were successfully modeled, 20 rats were randomly selected and divided into the model group and the Erchen decoction group with 10 rats in each group. The rats were fed with basic diet in normal control group. The rats in model group were given high-fat and high-sugar diet and given intraperitoneal injection of streptozotocin 30 mg·kg^-1 once to prepare the T2DM combined with NAFLD model. The rats in Erchen decoction group were given Erchen decoction (1.0 g·mL^-1 dried herbs per day). After 12 weeks, biochemical and oxidative stress indicators of rats were measured. HE staining was employed to evaluate the pathological changes of liver in rats. Immunohistochemistry, q-PCR, and Western blotting were used to measure the expression of SIRT1/UCP2 pathway in the liver tissues. RESULTS Compared with the model group, Erchen decoction ameliorated observably the body weight and the metabolic function of rats, and decreased the levels of FBG, ALT, AST, TG, TC, LDL-C, VLDL, FFA, FINS, HOMA-IR and MDA, HDL, SOD, GSH-Px and CAT were significantly increased. The HE staining results showed that hepatic tissues in the model group had severe steatosis. Erchen decoction alleviated hepatocyte steatosis. The immunochemistry, q-PCR, and Western blotting results showed that compared with the model group, the mRNA and protein expression of SIRT1 were significantly increased, as well as the mRNA and protein expression of UCP2 were significantly reduced in the Erchen decoction group. CONCLUSION Erchen decoction can improve the T2DM rats with NAFLD to some extent, the mechanism of which may be associated with the regulating of SIRT1/UCP2 pathway.