姜黄素类似物对糖尿病肾病小鼠肾纤维化的影响及机制探讨

目的:探讨姜黄素类似物对糖尿病肾病(DN)小鼠肾纤维化的影响及机制。方法:KKAy小鼠给予高脂饲料连续饲养2周构建DN小鼠模型,随机分为模型组和实验组,每组12只,10只C57BL/6J小鼠饲喂普通饲料,作为正常组。实验组小鼠灌胃姜黄素类似物H85 mg/kg,模型组和正常组均灌胃等量生理盐水,1次/d,连续干预6周。采用血糖仪检测小鼠空腹血糖(FBG),双缩脲法检测处死前24 h尿液尿蛋白(UP);过碘酸-无色品红染色(PAS染色)观察小鼠肾组织病理形态变化;蛋白免疫印迹(WB)法及实时荧光定量-聚合酶链式反应(qPCR)检测各组小鼠肾组织α-平滑肌肌动蛋白(α-SMA)、纤连蛋白(FN)和IV型胶原(Col-Ⅳ)、Twist蛋白表达情况。结果:干预后,正常组、模型组和实验组小鼠肾脏指数(KI)分别为(6.24±0.32)、(14.4±2.39)、(9.14±1.43)mg/g,FBG分别为(4.96±1.25),(35.54±3.43),(27.54±1.12)mmol/L,24 h UP分别为(31.69±5.51)、(710.54±231.28)、(410.43±130.36)μmol/L;肾小球硬化评分分别为(0.00±0.00)、(3.02±0.24)、(1.69±0.21)分,组间差异有统计学意义(P<0.05)。与正常组比较,模型组小鼠肾组织α-SMA、FN和Col-Ⅳ、Twist蛋白及mRNA相对表达量升高(P<0.05),而实验组小鼠低于模型组(P<0.05)。结论:姜黄素类似物可改善DN小鼠肾功能及肾组织损伤程度,降低纤维化蛋白表达,延缓肾组织纤维化,可能与下调Twist蛋白表达有关。

Exploration on Effects of Curcumin Analogs on Renal Fibrosis in Diabetic Nephropathy Mice and Its Mechanism

Objective:To explore effects and mechanism of curcumin analogs on renal fibrosis in diabetic nephropathy(DN)mice.Methods:KKAy mice were fed with high-fat diet for 2 weeks to establish DN mice model.They were randomly divided into model group and test group,with 12 mice in each group.Ten C57BL/6J mice were fed with common diet as normal group.Mice in the test group were given 5 mg/kg curcumin analogs H8 by gavage,and mice in the model group and the normal group were given the same amount of saline,once a day for 6 weeks.Fasting blood glucose(FBG)was measured by blood glucose meter.Before execution,24 h urinary protein(UP)was measured by biuret method.Renal histopathological changes were observed by periodic acid-Schiff staining(PAS staining).Expressions ofα-smooth muscle actin(α-SMA),fibronectin(FN),collagen IV(Col-IV)and Twist protein in renal tissue of mice in each group were measured by western blot(WB)and real-time fluorescent quantitative polymerase chain reaction(qPCR).Results:After the intervention,the kidney index(KI)of mice in the normal group,the model group and the test group was(6.24±0.32),(14.4±2.39)and(9.14±1.43)mg/g,respectively.The FBG was(4.96±1.25),(35.54±3.43)and(27.54±1.12)mmol/L,respectively.The 24 h UP was(31.69±5.51),(710.54±231.28)and(410.43±130.36)μmol/L,respectively.The glomerulosclerosis score was(0.00±0.00),(3.02±0.24)and(1.69±0.21),respectively.There was statistically significant difference between the groups(P<0.05).Compared with the normal group,the relative expressions ofα-SMA,FN,Col-IV,Twist protein and mRNA in kidney tissue of the model group mice were increased(P<0.05),while those in the test group were lower than those in the model group(P<0.05).Conclusion:Curcumin analogs can improve renal function and damage degree of renal tissue in DN mice,decrease the expression of fibrosin and delay renal fibrosis,which may be related to down-regulation of Twist protein expression.