胰岛素样生长因子-Ⅰ对人肾小管上皮细胞转分化及胶原合成的作用

Effect of insulin-like growth factor I on the transdifferentiation and collagen synthesis of human renal tubular epithelial cells

目的探讨胰岛素样生长因子-Ⅰ(IGF-Ⅰ)在人肾小管上皮细胞转分化及胶原合成中的作用。方法将体外培养的人肾小管上皮细胞HK2分为2组(1)对照组;(2)IGF-Ⅰ组培养液中加入终浓度分别为25、50、100、200μg/L的IGF-Ⅰ。用倒置显微镜观察细胞形态变化,以RT-PCR检测HK2细胞α-平滑肌肌动蛋白(α-SMA)、胶原Ⅰα和胶原ⅢαmRNA表达的变化。ELISA方法检测培养上清中胶原Ⅰ的浓度。结果IGF-Ⅰ刺激使HK2细胞由椭圆形变为梭形。不同浓度的IGF-Ⅰ作用于HK2细胞48h后,α-SMA、胶原Ⅰα和胶原ⅢαmRNA水平显著升高(P<0.05);ELISA结果显示,100及200μg/LIGF-Ⅰ组中HK2细胞分泌的胶原Ⅰ显著增加(P<0.05)。结论IGF-Ⅰ在体外能够诱导人肾小管上皮细胞转分化,并促进其胶原的合成。

AIM： To investigate the role of insulin-like growth factor Ⅰ （ IGF- Ⅰ ） in transdifferentiation and collagen synthesis of human renal tubular epithelial cell line HK2 in vitro. METHODS： Cultured HK2 cells were divided into two groups： （1） control group; （2） IGF- Ⅰ -treated group（25, 50, 100, 200 ug/L, respectively）. The cell morphological changes were traced with inverted microscope, and the expression of α-smooth muscle actin （ α-SMA）, collagen Ⅰ α and collagen Ⅲα mRNA was detected by RT-PCR. Concentration of collagen Ⅰ secreted into the culture supernatant was determined by ELISA. RESULTS： In HK2 cells, IGF- Ⅰ stimulated the morphlolgical oval-to-fusiform transdifferentiation of the cells, and upregulated c（-SMA, collagen Ⅰ c（ and collagen Ⅲα mRNA expression（ P 〈 0.0.5 ）. Secreted collagen Ⅰ level was also up-regulate by IGF- Ⅰ in the concentration of 100 and 200 ug/L, recpectively. CONCLUSION： IGF-Ⅰ can promote the transdifferentiation of human renal tubular epithelial cells and stimulate the synthesis of collagen.