【摘要】 目的:探讨胞膜小凹(caveolae)在高糖(HG)诱导大鼠肾小球系膜细胞(MCs)细胞外基质(extra-cellular matrix,ECM)表达过程中的作用。方法:传代培养的大鼠MCs同步化后分为:(1)正常糖组;(2)HG组;(3)HG+甲基-β-环糊精(β-MCD)组;(4)HG+β-MCD+胆固醇组。用Western blotting检测小凹蛋白1(Cav-1)、磷酸化小凹蛋白1(p-Cav-1-Y14)和Ⅰ型胶原(ColⅠ)蛋白的表达水平,用实时定量PCR检测细胞中Cav-1 mRNA表达变化,用ELISA方法检测上清中纤维连接蛋白(FN)的蛋白含量。结果:(1)高糖状态下,系膜细胞FN和ColⅠ蛋白表达水平均显著增加(均P<0.05)。(2)高糖培养显著增加p-Cav-1-Y14水平(P<0.01),而对Cav-1 mRNA及蛋白表达无明显影响(P>0.05)。(3)β-MCD预处理抑制了高糖诱导的p-Cav-1-Y14升高(P<0.01)及FN表达(P<0.05),但对高糖诱导的Col I表达无影响;β-MCD的作用可被胆固醇抑制。结论:高糖可显著增加系膜细胞1型胶原及纤维连接蛋白的合成。高糖诱导的纤维连接蛋白合成与Cav-1磷酸化水平增加有关。更多还原

【Abstract】 AIM: To investigate the role of caveolae in high glucose(HG)-induced extracellular matrix(ECM) production in rat mesangial cells(MCs).METHODS: Synchronized rat MCs were divided into normal glucose group,HG group,HG+methyl-β-cyclodextrin(β-MCD) group and HG+β-MCD+cholesterol(Chol) group.Western blotting was used to detect the protein expression of caveolin-1(Cav-1),phosphorylated caveolin-1(p-Cav-1-Y14) and collagen type 1(Col I).The mRNA expression of Cav-1 was determined by real-time PCR.ELISA was used to measure the level of fibronectin(FN) in the supernatant.RESULTS: High glucose significantly increased the expression of FN and Col I.In HG 12,24 and 48 h groups,the mRNA and protein levels of Cav-1 were not significantly different from those in HG 0 h group,whereas the level of p-Cav-1-Y14 was significantly increased.β-MCD significantly attenuated HG-induced elevation of p-Cav-1-Y14 and FN production,but had no effect on HG-induced Col I expression.All these responses to β-MCD were abolished by Chol.CONCLUSION: High glucose significantly increases the production of Col I and FN in rat MCs.FN production induced by high glucose is mediated by p-Cav-1-Y14.更多还原