摘要目的 观察c-Jun氨基末端激酶(JNK)-c-Jun通路对连接蛋白43(Cx43)表达的影响及在转化生长因子(TGF)β1诱导的肾小管上皮细胞-肌成纤维细胞转分化(TEMT)中的作用.方法 大鼠肾小管上皮细胞(NRK-52E)随机分成3组:对照组、TGF-β1(10μg/L)组和TGF-β1(10 μg/L)+JNK选择性抑制剂SP600125(50 μmol/L)组.用免疫细胞化学、Western印迹检测JNK、c -Jun、连接蛋白43( Cx43)、上皮细胞标志物E-钙黏蛋白(E-cadherin)和肌成纤维细胞标志物α-SMA的表达.用RT-PCR检测Cx43的mRNA水平.用激光共聚焦显微镜荧光漂白恢复( FRAP)技术检测NRK-52E细胞间通讯功能.结果 TGF-β1引起肾小管上皮细胞α-SMA、JNK、c-Jun表达上调(均P＜0.05),Cx43、E-cadherin表达下调(均P＜0.05),Cx43的mRNA水平下降(P＜0.05),细胞间通迅功能下降(P＜0.05).JNK抑制剂处理后,上述改变明显减轻.结论 TGF-β1引起肾小管上皮细胞内JNK表达上调,增加c-Jun活性,从而抑制Cx43的表达和降低细胞间通迅功能,导致TEMT.

abstractsObjective To explore the effect of JNK-c-Jun signal pathway on connexin 43 (Cx43) expression and its role in renal tubular epithelial-myofibroblast transition (TEMT) induced by TGF-β1. Methods Normal rat kidney tubular epithelial cells (NRK-52E) were cultured in Dulbecco's modified eagle medium (DMEM) with 10％ fetal bovine serum,then were randomly divided into 3 groups: control group,TGF-β1 group (treated with TGF-β1 10 μg/L),and TGF-β1+SP600125 (selective JNK inhibitor,50 μmol/L) group. The protein expressions of JNK,c-Jun,α-SMA,Cx43 and E-cadherin were assayed by immunocytochemistry and Western blotting.The Cx43mRNA was assayed by RT-PCR.Gap junction intercellular communication (CJIC) was measured by fluorescence recovery after photobleaching assay (FRAP). Results TGF-β1 increased the expressions of JNK,c-Jun and α-SMA (P＜0.05),reduced the expressions of Cx43 and E-cadherin (P＜0.05),and inhibited GJIC of NRK-52E (P ＜0.05).SP600125 could alleviate the above expressions changes and enhanced GJIC induced by TGF-β1. Conclusion JNK-c-Jun signal pathway induces TEMT of NRK-52E treated with TGF-β1 via down-regulation of connexin 43expression and inhibition of GJIC.