同源盒基因 A13在清蛋白超载所致肾小管上皮细胞间充质转分化中的作用

Role of homeobox A13 in epithelial - to - mesenchymal transition induced by serum albumin overload in hu-man renal tubular epithelial cells

目的：探讨核转录因子同源盒基因 A13（HOXA13）基因在清蛋白（HSA）诱导的肾小管上皮细胞（HKC）间充质转分化中的作用。方法采用 Western blot 印迹分析检测不同水平 HSA（0 g/ L、1 g/ L、5 g/ L、10 g/ L、20 g/ L、30 g/ L）刺激 HKC 48 h，以及20 g/ L HSA 刺激 HKC 不同时间（0 h、12 h、24 h、48 h、72 h）后， HKC 细胞角蛋白（CK）、波形蛋白（Vimentin）和 HOXA13蛋白的表达情况。采用脂质体转染技术上调 HKC 细胞 HOXA13表达后，观察 HSA 刺激后 CK、Vimentin 表达水平的变化。结果1. HSA 以质量浓度和时间依赖方式下调 CK 表达，同时上调 Vimentin 表达。2. HSA 以质量浓度和时间依赖方式下调 HOXA13表达，HSA 水平为5 g/ L、10 g/ L、20 g/ L、30 g/ L 时，HOXA13水平分别为未刺激前的58.24％（ P ＝0.005）、44.73％（ P ＝0.003）、38.40％（P ＝0.033）和24.83％（P ＝0.011）；作用24 h、48 h、72 h 时，HOXA13水平分别为未刺激前的52.00％（P ＝0.023）、46.83％（P ＝0.008）、35.10％（P ＝0.034）。3. HOXA13蛋白表达与 CK 蛋白表达呈正相关（r ＝0.86，P ＝0.005），与 Vimentin 蛋白表达呈负相关（r ＝-0.94，P ＝0.002）。4.基因转染上调 HKC 细胞HOXA13表达后，HSA 下调 CK 表达和上调 Vimentin 表达作用受到明显抑制，抑制程度分别为360.00％（P ＝0.005）和35.34％（P ＝0.005）。结论 HSA 超载所致 HKC 间充质转分化可能通过 HOXA13途径起作用。

Objective To explore the role of nuclear translational factor homeobox A13（HOXA13）gene in epithelial - to - mesenchymal transition（EMT）induced by human serum albumin（HSA）overload in human renal tu-bular epithelial（HKC）cells. Methods HKC cells were treated with different concentrations of HSA（ranging from 0 - 30 g/ L）for 48 h or 20 g/ L HSA for different times（ranging from 0 - 72 h）in vitro. The protein expressions of cy-tokeratin（CK）,Vimentin,and HOXA13 protein in HKC cells were detected by using Western blot respectively. Mean-while,liposome - mediated DNA transfection was used to transfect the HOXA13 gene into HKC cells before HSA treat-ment,and the expressions of CK,Vimentin and HOXA13 protein in HKC cells were also detected by using Western blot. Results （1）The protein expression of CK decreased but Vimentin increased after HKC cells were exposed to HSA,which was in a concentration - and time - dependent manner.（2）Expression of HOXA13 was down - regulated by HSA in a dose - and time - dependent manner,and the expressions of HOXA13 protein in HKC in 5 g/ L,10 g/ L, 20 g/ L,30 g/ L group were 58. 24%（P = 0. 005）,44. 73%（P = 0. 003）,38. 40%（P = 0. 033）and 24. 83%（P =0. 011）respectively as compared with 0 g/ L group. Likewise,the protein expressions of HOXA13 in 24 h,48 h,72 h group were 52. 00%（P = 0. 023）,46. 83%（P = 0. 008）and 35. 10%（P = 0. 034）respectively as compared with 0 h group.（3）There was a positive correlation between the levels of HOXA13 protein expression and CK protein expression （r = 0. 86,P = 0. 005）,while the relationship between the levels of HOXA13 protein expression and Vimentin protein expression was negative（r = - 0. 94,P = 0. 002）.（4）Up - regulated expression of HOXA13 in HKC cells by lipo-fectamine transfection alleviated the degree of EMT induced by HSA significantly. The expression of Vimentin decreased by 35. 34%（P = 0. 005）while the expression of CK increased 360. 00% - fold（P = 0. 005）,compared with that of untransfected HKC cells. Conclusion EMT induced by HSA in HKC cells may play a role through HOXA13.