内质网应激在高糖诱导人肾脏系膜细胞表型转化中的作用

Effect of endoplasmic reticulum stress on phenotypic change of cultured human glomerular mesangial cells induced by high glucose

目的探讨内质网应激在高糖诱导人肾脏系膜细胞表型转化的作用。方法将体外培养的人肾脏系膜细胞分为对照组、高糖组（HG组）、高糖＋4-苯基丁酸（4-PBA）＋预绀（4一PBA组）。MTT法测定细胞增殖率，流式细胞术观察细胞周期变化，免疫组织化学染色激光共聚焦显微镜观察细胞仅平滑肌肌动蛋白（α—SMA）表达情况，实时荧光定量PCR和Western印迹分别检测mRNA和蛋白表达。结果（1）高糖组系膜细胞增殖率和进入S期比例显著高于对照组（P〈0．05），同时，高糖能刺激饯一SMA表达增加（P〈0．05）；4一PBA干预可明显抑制高糖刺激的系膜细胞增殖和进入S期及α-SMA表达。（2）相对于对照组，高糖能刺激系膜细胞葡萄糖调节蛋白78（Grp78）mRNA和蛋白表达增加（P〈0．05）；4一PBA干预可显著下调这种效应（P〈0．05）。（3）高糖可诱导系膜细胞转化生长因子（TGF-β1）、纤连蛋白（FN）mRNA和蛋白表达（P〈0．05）；4-PBA干预则明显下调其表达（P〈0．05）。结论内质网应激在高糖诱导人肾脏系膜细胞表型转化效应中发挥了重要作用。

Objective To study the role of endoplasmic reticulum stress in phenotypic change of cultured human glomerular mesangial cells induced by high glucose. Methods Cultured human glomerular mesangial cells were divided into three groups： control group, high glucose group and high glucose＋ 4-phenylbutyric acid （4-PBA） group. Cell number of proliferation was assessed by MTF assay. Cell cycle was measured by flow eytometrie analysis. Expression of α-SMA was assessed by immunohistochemistry and was observed by laser scanning confocal microscope. Involved mRNA and protein expression were measured by real-time PCR and Western blotting. Results （1）Cell number of proliferation and S transition proportion in high glucose group significantly increased than that in control group （P 〈 0.05）. High glucose could induce α-SMA expression significantly （P〈0.05）. 4-PBA could significantly inhibit human glomerular mesangial cells proliferation （P〈0.05）, S transition arrest （P〈0.05） and expression of α-SMA （P〈 0.05） induced by high glucose. （2） Compared with control group, high glucose could significantly increase the expression of glucose-regulated proteiu78（Grp78） mRNA and protein （P〈 0.05）, which could be inhibited by 4-PBA treatment （P〈0.05）. （3）High glucose could induce the mRNA and protein expression of TGF-β1 and FN significantly, which could be inhibited by 4-PBA treatment（P〈0.05）. Conclusion Endoplasmic reticulum stress plays an important change of cuhured human glomerular mesangial cells induced by high glucose.