α-硫辛酸对高糖诱导的肾小管上皮细胞转分化影响的研究

摘要

目的 探讨α-硫辛酸(ALA)对高糖诱导的肾小管上皮细胞转分化的影响. 方法 体外培养人肾小管上皮细胞株(HKC)分别予正常糖(NG组)、高糖(HG组)、高糖+ALA(100、200、400μmol/L)组或高糖+甘露醇(M组)干预48 h；观察HKC细胞形态改变,RT-PCR检测结缔组织生长因子(CTGF)和α-平滑肌肌动蛋白(α-SMA) mRNA的表达,免疫荧光染色检测α-SMA蛋白表达. 结果 高糖刺激使HKC细胞由铺路石样变为梭形长条状；ALA干预可部分逆转高糖对HKC细胞形态的影响.HG组干预HKC细胞的CTGF及α-SMA mRNA表达水平较NG组增强,高糖+ALA组表达均较HG组减弱,且呈浓度依赖性(P＜0.01)；HG组α-SMA表达增强,NG组表达微弱,高糖+ALA组表达渐次减弱,差异均有统计学意义(P＜0.01)；M组上述指标与NG组比较差异均无统计学意义. 结论 ALA可阻断高糖诱导的肾小管上皮细胞转分化,对糖尿病慢性肾脏疾病(CKD)的防治可能具有一定作用.%Objective To investigate the effects of α-lipoic acid on transdifferentiation of renal tubular epithelial cell induced by high-glucose.Methods Human renal tubular epithelial cells (HKC) were cultured in DMEM medium and divided into six groups:normal glucose group (5.5 mmol/L),mannitol group (5.5 mmol/L glucose plus 19.5 mmol/L mannitol),high glucose group (25 mmol/L),and α-lipoic acid groups (high glucose with 100 μmol/L,200 μmol/L and 400 μmo1/L α-lipoic acid respectively).The morphology of HKC was observed under phase contrast microscope at 48 h after different treatments.The mRNA expressions of CTGF and α-SMA were also measured by RT-PCR.The expressions of α-SMA in HKC were observed at 48 h by laser scanning confocal microscopy and analyzed by fluorescence quantitative software.Results The morphology of HKC were transformed from cube to fusiform shape stimulated by high glucose,and were reversed by intervention of 100～400 μmol/L α-lipoic acid.RT-PCR indicated that the expressions of CTGF mRNA and α-SMA mRNA were increased significantly in high glucose group compared with normal glucose group (P＜0.01),and were inhibited by different concentrations of α-lipoic acid with concentration dependent manner (P＜0.01).Immunofluorescence detection showed the expression of α-SMA in HKC reinforced in high glucose group,and attenuated by different concentrations of α-lipoic acid.Meanwhile mannitol group showed no differences in those indexes compared with normal glucose group.Conclusion The high-glucose induces transdifferentiation of human renal tubular epithelial cells in vitro and α-lipoic acid prevents renal tubular epithelial cell from transdifferentiation.It may be helpful in treatment of chronic kidney disease in diabetes.