内源性结缔组织生长因子介导转化生长因子β_1对肾小管上皮细胞的转分化效应

Effects of endogenous connective tissue growth factor on renal tubular epithelial- myofibroblast transdifferentiation regulated by transforming growth faltor β_1 in vitro

目的:探讨内源性结缔组织生长因子(CTGF)在人肾小管上皮细胞(HK2)转分化过程中的作用。方法:将HK2细胞分为4组:对照组;转化生长因子β1(TGF-β1)5ng/ml刺激组;TGF-β15ng/ml刺激+CTGF反义ODN3mmol/L干预组;TGF-β15ng/ml刺激+CTGF正义ODN3mmol/L对照组。用倒置显微镜观察各组细胞的形态学变化,用RT-PCR检测各组细胞中CTGF、上皮细胞钙粘蛋白(E-cadherin)、α-平滑肌肌动蛋白(α-SMA)、纤连蛋白(FN)mRNA表达变化。结果:TGF-β1刺激使HK2细胞形态由椭圆形转为梭形;下调E-cadherinmRNA表达,上调CTGF、α-SMA和FNmRNA表达,且CTGFmRNA表达变化在时间上早于E-cadherin、α-SMA和FNmRNA表达变化;CTGF反义ODN可对抗TGF-β1引起的细胞形态学改变和E-cadherin、CTGF、α-SMA、FNmRNA表达变化效应。结论:内源性CTGF介导了TGF-β1对HK2细胞的转分化效应。

Objective： To investigate the significance of endogenous connective tissue growth factor （CTGF） in epithel ial- myofibroblast transdifferentiation of human renal tubular epithelial cell line （HK2） in vitro. Methods：Cultured HK2 were divided into four groups： （ 1 ）control; （2）treated with TGF-β1 （5 ng/ml） ; （3）treated with TGF-β1 （5 ng/ml） plus CTGF antisense oligonucleotide （3 mmol/L）; （4）treated with TGF-β1 （5 ng/ml） plus CTGF sense oligonucleotide （3 mmol/L）. The cell morphological changes were traced with inverted microscope, and the expression of CTGF.E-cadherin.α-smooth muscle actin （α-SMA） and fibronectin（FN） mRNAs were detected by RT-PCR. Results： In HK2 cells, TGF-β1 stimulated the oval-to-fusiform transdifferentiation in morphology, downregulated E-cadherin mRNA expression, upregulated CTGF, α-SMA and FN mRNAs expression. The presence of the change of CTGF mRNA expression preceded those of E-cadherin.α-SMA and FN mRNAs; CTGF antisense oligonucleotide inhibited these effects by TGF-β1. Conclusion：Endogenous CTGF mediates the regulation of transforming growth factor β1 in human renal tubular epithelial-myofibroblast transdifferentiation in vitro.