高糖诱导肾小管上皮细胞转化的作用

Study on qualitative alteration in renal tubular epithelial cell induced by high glucose

目的观察高糖诱导肾小管上皮的转化，以及转化生长因子13，（TGF-β1）和信号转导蛋白（Smad）受体激活锚定蛋白（SARA）的变化。方法建立高糖诱导肾小管上皮细胞（HKC）转化模型，高糖处理HKC0、12、24、48h后提取总蛋白，Westernblot法检测波形蛋白、钙黏附蛋白、TGF—β1、SARA和Smad2蛋白的表达。结果Westernblot法检测高糖处理HKC0、12、24、48h后，钙黏附蛋白的相对表达量分别为1．13±0．31、0．74±0．1g、0．63±0．18、0．32±0．12，各组之间两两比较差异均有统计学意义（P均〈0．05）；波形蛋白相对表达量分别为0．23±0．09、0．34±0．04、0．83±0．15、1．02±0．22，各组之间两两比较差异均有统计学意义（P均〈0．05）；TGF—B1蛋白的相对表达量分别为0．25±O．08、0．44±O．12、0．72±0．21、0．92±0．28，各组之间两两比较差异均有统计学意义（P均〈0．05）；SARA蛋白的相对表达量分别为0．83±0．21、0．54±0．13、0．42±0．09、0．35±0．12，各组之间两两比较差异均有统计学意义（P均〈0．05）；Smad2蛋白的相对表达量分别为1．14±0．22、0．82±0．15、0.61±0．17、0．30±0．13，各组之间两两比较差异均有统计学意义（P均〈0．05）。结论高糖可诱导HKC转化，TGF—β1通路的激活可能是其主要的作用机制，SARA蛋白的下调和继发的Smad2蛋白降解协同了TGF—β1通路的致纤维化作用。

Objective To investigate the effect of transforming growth factor-β1 （ TGF-β1 ） and Smad anchor for receptor activation（SARA） in high glucose induced epithelium to mensenchymal transition（EMT） in proximal tubule HKC ceils. Methods The model of EMT in HKC ceils by high glucose treatment was developed. After stimulation by 25 mmol/L glucose for 0, 12,24, and 48 h, the cells were collected and total protein was extracted. Vimentin, E-cadherin ,TGF-131 , SARA and Smad2 expression were detected by western blot analysis. Results At 0,12,24, and 48 h after treated with 25 mmol/L glucose the expression of E-cadherin was 1.13 ±0. 31,0. 74±0. 14,0. 63 ±0. 18 and 0. 32 ±0. 12 respectively,with significantly difference between each group （ Ps 〈 0. 05 ） ; the expression of vimentin in HKC cells increased from 0. 23 ± 0.09,0. 34 ± 0. 04,0. 83 ± 0. 15 to 1.02 ±0. 22 signifiantly（Ps 〈 0. 05）. High glucose treatment also upregulated the protein expression of TGF-β1 ,with expression of 0. 25± 0. 08,0. 44 ±0. 12,0. 72± 0. 21, and 0. 92 ±0. 28 after treated with 25 mmol/L glucose for 0,12,24, and 48 h （ Ps 〈 0. 05 ）. The protein expression of SARA significanhy decreased from 0. 83 ±0. 21,0. 54 ±0. 13,0.42 s0. 09 to 0. 35 s0. 12（Ps 〈0. 05） ,and the protein expression of Smad2 also significantly decreased from 1.14 ±0. 22,0. 82 ± 0. 15,0. 61 ±0. 17 to 0. 30 ±0. 13 （ Ps 〈 0. 05 ）. Conclusion The upregulation of TGF-β1 might play a key role in high glucose induced EMT in proximal tubule HKC cells. The downregulation of SARA and Smad2 protein might contribute to TGF-β1 mediated renal fibrosis.