同源盒基因A13转染对肾小管上皮细胞间充质转化和骨形成蛋白7表达的影响

Effect of Homeobox A13 transfection on epithelial-mesenchymal transition and bone morphogenetic protein-7 expression in kidney tubular epithelial cells

目的探讨转染同源盒基因A13(HOXA13)对人血清白蛋白(HSA)诱导的人肾小管上皮细胞(HKC)间充质转化(EMT)和骨形成蛋白7(BMP-7)表达的影响。方法体外培养的HKC细胞株经人血清白蛋白(20 mg/m L)作用48 h后,采用免疫印迹法检测HKC细胞角蛋白(CK)、波形蛋白(vimentin)和HOXA13蛋白的表达。应用脂质体转染技术上调HKC细胞HOXA13表达,观察HOXA13不同表达水平对人血清白蛋白超载诱导CK、vimentin、BMP-7表达改变的影响。结果 20 mg/m L HSA刺激HKC细胞48 h后,HKC细胞出现EMT样改变:CK表达下降(P<0.01)、vimentin表达增高(P<0.01);HSA超载同时使HKC细胞内HOXA13、BMP-7表达下降。HOXA13转染上调HKC细胞内HOXA13表达后,显著抑制了HSA超载诱导的EMT发生(P<0.05)和BMP-7表达的下降(P<0.05)。结论转染HOXA13可拮抗白蛋白超载诱导HKC细胞发生EMT的作用,这种作用可能与HOXA13上调BMP-7表达有关。

Objective To examine the transfection of Homeobox A13（HOXA13） on epithelial-mesenchymal transition（EMT） and the expression of bone morphogenetic protein-7（BMP-7） induced by albumin-overload in human kidney tubular epithelial cells（HKCs）. Methods The cultured HKCs were treated with 20 mg/m L human serum albumin（HSA） for 48 hours. Protein expression of cytokeratin（CK）, vimentin and HOXA13 in the HKCs was assessed by Western blot. Protein expression of CK, vimentin, and BMP-7 was also detected in HKCs transfected with lipofectamine contained HOXA13 DNA. Results HSA induced EMT in HKCs, presented by decreased CK expression（P〈0.01） and increased vimentin expression（P〈0.01）. The up-regulated expression of HOXA13 transfected by lipofectamine inhibited the level of EMT induced by HSA in HKCs（P〈0.05）. The decreased rate of BMP-7 protein expression induced by HSA was inhibited by over-expressed HOXA13 in HKCs（P〈0.05）. Conclusions Transfection of HOXA13 in HKCs could inhibit the degree of EMT induced by albumin-overload, possibly by increasing BMP-7 expression.