益气养阴方对2型糖尿病大鼠脂代谢的影响

目的:观察药食同源益气养阴方对高脂饲料联合链脲佐菌素(STZ)腹腔注射建立的2型糖尿病(T2DM)大鼠模型脂代谢的影响,探讨其在调控脂代谢方面的作用机制。方法:高脂饲料喂养大鼠4周,腹腔注射STZ制备T2DM大鼠模型。糖尿病大鼠随机分为模型组、益气养阴高、中、低剂量组(9.00,4.50,2.25 g·kg^-1)和二甲双胍组(0.20 g·kg^-1),另设正常组。益气养阴方高、中、低剂量组分别给予口服不同剂量的益气养阴方颗粒,二甲双胍组给予二甲双胍,模型组、正常组均给予同体积生理盐水干预。连续灌胃3周,测定体质量、血糖,全自动生化分析仪检测甘油三酯(TG),总胆固醇(TC),低密度脂蛋白胆固醇(LDL-C),高密度脂蛋白胆固醇(HDL-C),天门冬氨酸氨基转移酶(AST),丙氨酸氨基转移酶(ALT),碱性磷酸酶(ALP),总蛋白(TP)的含量;苏木素-伊红(HE)染色观察各组肝脏组织病理变化情况;PAS染色观察肝脏组织肝糖原病理变化情况;油红O染色观察肝脏组织脂质变化情况;蛋白免疫印迹法(Western blot)观察肝脏组织腺苷酸活化蛋白激酶(AMPK)/固醇调节元件结合蛋白1c(SREBP-1c)/乙酰辅酶A羧化酶1(ACC1)/过氧化物酶体增殖激活受体α(PPARα)通路蛋白表达情况。结果:与正常组比较,模型组TG,TC,LDL-C,AST,ALT,ALP含量明显升高,HDL-C含量明显降低(P<0.05,P<0.01),与模型组比较,益气养阴方各组可显著降低大鼠血清中TG,LDL-C含量(P<0.05,P<0.01),显著增加HDL-C含量(P<0.05);组织形态学检测显示,益气养阴方对肝脏中肝细胞胞间空泡、脂肪变性程度显著减轻,肝脏组织脂质区域显著缩小;与正常组比较,模型组肝脏组织中p-AMPKα,PPARα,SREBP-1(浆)蛋白表达显著降低,p-ACC1,SREBP-1(核)蛋白表达显著升高(P<0.01);与模型组比较,益气养阴方对肝脏组织中p-AMPKα,PPARα,SREBP-1(浆)蛋白表达显著升高(P<0.05,P<0.01),p-ACC1,SREBP-1(核)蛋白表达显著降低(P<0.05,P<0.01)。结论:益气养阴方对高脂饲料联合STZ引起的T2DM大鼠血脂升高具有明显的降低作用;T2DM大鼠血脂的降低可能与影响大鼠肝脏AMPK/ACC1/SREBP-1/PPARα通路有关。

Effect of Yiqi Yangyin Prescription on Lipid Metabolism in Rats with Type 2 Diabetes

Objective:To observe the effect of Yiqi Yangyin prescription on lipid metabolism in type 2 diabetes rat model induced by high fat diet combined with intraperitoneal injection of streptozocin(STZ),and explore its mechanism in regulation of lipid metabolism. Method: The rats were fed with high-fat diet for 4 weeks,and intraperitoneal injection of STZ was provided to establish diabetes model. The diabetic rats were randomly divided into model group,Yiqi Yangyin prescription high dose group,medium dose group and low dose group(9.00,4.50,2.25 g·kg^-1)and metformin group(0.20 g·kg^-1). Another blank control group was set up. The high,medium and low dose groups were given with different oral doses of Yiqi Yangyin prescription granules,metformin was given in metformin group,the model group and the blank group received the same volume of normal saline. Intragastric administration was given for three weeks,and then the weight and blood glucose were measured. Automatic biochemical analyzer was used to detect triglyceride(TG),total cholesterol(TC),low density lipoprotein cholesterol(LDL-C),high density lipoprotein cholesterol(HDL-C),aspartate aminotransferase(AST),alanine aminotransferase(ALT),alkaline phosphatase(ALP),and content of total protein(TP). Hematoxylin-eosin(HE)staining was used to observe the pathological changes of liver tissues in each group. Periodic acid-schiff stain(PAS)staining was used to observe the pathological changes of liver glycogen. The lipid changes of liver tissues were observed by oil red O staining. The expression of adenosine monophosphate activated protein kinase(AMPK)/sterol regulatory element binding protein 1 c(SREBP1 c)/acetyl-coenzyme A carboxylase(ACC1)/peroxisome proliferator activated re-ceptor α(PPARα)pathway in liver tissues was observed by Western blot. Result:Compared with the blank group,TG,CHO,LDL-C,AST,ALT and ALP significantly increased and HDL-C significantly decreased in the model group(P<0.05,P<0.01).Compared with the model group,TG and LDL-C contents significantly decreased(P<0.05,P<0.01)and LDL-C contents significantly increased in Yiqi Yangyin prescription groups(P<0.05). Histomorphology showed that Yiqi Yangyin prescription significantly reduced the degree of hepatocyte intercellular vacuoles and steatosis in liver,and significantly reduced the lipid area of liver tissue. Compared with the blank group,the protein expression levels of p-AMPKα,PPARα,SREBP-1(plasma)in the liver tissues significantly decreased in the model group,but such expression levels increased after treatment with Yiqi Yangyin prescription(P<0.05,P<0.01),compared with the blank group,the protein expression levels of p-ACC1 and SREBP-1(nuclear)significantly increased(P<0.01)in model group,but such expression significantly decreased after treatment with Yiqi Yangyin prescription(P<0.05,P<0.01). Conclusion: Yiqi Yangyin prescription can significantly reduce blood lipid in the diabetic rats caused by high-fat feed combined with STZ. The decrease of blood lipid in the type 2 diabetes rats may be related to the influence on AMPK/ACC1/SREBP-1/PPAR pathway in rat liver.