槲皮素脂质体对糖尿病肾病氧化应激和TGF-β1/Smad7通路的影响

目的 观察槲皮素脂质体(LQ)对糖尿病肾病氧化应激和转化生长因子-β1(TGF-β1)/Smad7通路的影响.方法 高糖高脂饮食联合腹腔注射链脲佐菌素(STZ)制备大鼠2型糖尿病肾病模型,随机分为糖尿病模型组(DM组)、槲皮素脂质体组(LQ组)和厄贝沙坦组(IRB组),另设正常组.8周后生化法测定各组大鼠血清中总胆固醇(TC)、三酰甘油(TG)、高密度脂蛋白(HDL)、低密度脂蛋白(LDL)、超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-Px)水平,免疫组化检测大鼠肾脏TGF-β1和Smad7蛋白的表达,RT-PCR法检测大鼠肾皮质TGF-β1和Smad7 mRNA的表达情况.结果 与正常组比较,DM组大鼠血清中HDL、SOD、GSH-Px活性水平显著下降,TC、TG、LDL、MDA含量明显升高,肾组织TGF-β1蛋白及TGF-β1 mRNA表达均显著增高,Smad7蛋白及Smad7 mRNA表达减少.与DM组比较,LQ组和IRB组HDL、SOD、GSH-Px活性水平升高,TC、TG、LDL、MDA含量降低,肾组织TGF-β1蛋白及TGF-β1 mRNA减少,Smad7蛋白及Smad7 mRNA表达增加.结论 LQ通过减轻体内氧化应激反应,干预TGF-β1和Smad7通路从而对糖尿病肾病起保护作用.

Effects of quercetin liposomes on oxidative stress andTGF-β1/Smad7 pathway in kidney of diabetic rats

Objective To observe the effects of quercetin liposomes (LQ) on oxidative stress and TGF-β1/Smad7 pathway in kidney of diabetic rats.Methods The model of type 2 diabetic rats were established by being fed on high-sugar and high-fat diet combined with intraperitoneally injection of streptozotocin.Then type 2 diabetic rats were randomly divided into three groups: diabetic model group (group DM), quercetin liposomes group (group LQ), irbesartan group (group IRB).The other normal control group (group N) was established.After 8 weeks,the serum levels of total cholesterol(TC), triglycerides(TG), high-density lipoprotein(HDL), low-density lipoprotein(LDL), superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px) were measured by biochemical methods.Immunohistochemistry was used to detect expressions of TGF-β1 and Smad7 protein in kidney cortex of diabetic rats.RT-PCR was used to detect expressions of TGF-β1 and Smad7 mRNA in renal cortex of diabetic rats.Results Compared with the group N, the serum levels of HDL, SOD, GSH-Px decreased significantly in group DM, while the serum levels of TC, TG, LDL, MDA increased significantly;the expression levels of TGF-β1 protein and TGF-β1 mRNA in kidney tissue increased significantly, while the expression levels of Smad7 protein and Smad7 mRNA decreased significantly.Compared with the group DM, the serum levels of HDL, SOD, GSH-Px increased significantly in group LQ and IRB, while the serum levels of TC, TG, LDL, MDA decreased;the expression levels of TGF-β1 protein and TGF-β1 mRNA in kidney tissue decreased significantly, while the expression levels of Smad7 protein and Smad7 mRNA increased significantly.Conclusion LQ protects against diabetic nephropathy by reducing the oxidative stress, interfering with the TGF-β1 and Smad7 pathway.