醛固酮对人肾小管上皮细胞MMP-1/TIMP-1基因表达和合成分泌纤维连接蛋白的影响

Effects of aldosterone on gene expressions of MMP-1/TIMP-1 and secretion of fibronectin in cultured human renal tubular epithelial cells

目的探讨醛固酮(ALD)对人肾小管上皮细胞基质金属蛋白酶1(MMP-1)和金属蛋白酶1组织抑制剂(TIMP-1)基因表达,以及合成分泌纤维连接蛋白(FN)的影响。方法人肾小管上皮细胞(HK-2)培养于含5%FCS的DMEM/F12培养液中,以不同浓度的ALD(10-11、10-10、10-9、10-8mol/L)刺激HK-2细胞48h后,应用半定量RT-PCR法检测细胞中MMP-1、TIMP-1和FN的基因表达,ELISA法测定培养上清液中纤维连接蛋白(FN)的含量。结果 ALD呈剂量依赖性地下调HK-2细胞中MMP-1的基因表达,上调TIMP-1和FN的基因表达,MMP-1/TIMP-1比值降低(P<0.05)。ALD呈剂量依赖性地增加培养上清液中FN的含量(P<0.05)。结论 ALD通过调控HK-2细胞中MMP-1和TIMP-1的基因表达,促进其合成分泌FN,导致肾间质纤维化的进展。

To investigate the effects of aldosterone （ALD） on gene expressions of matrix metallopro- teinase-1 （MMP-1） and tissue inhibitor of metalloproteinase-1 （TIMP-1） and synthesis and secretion of fibronectin （FN） in cultured human renal tubular epithelial cells. [ Methods ] Human renal tubular epithelial cells （HK-2） were cultured in DMEM/F12 medium supplemented with 5% FCS. Cells were exposed to different concentrations of ALD （0, 10-＂, 10-l~, 10~9 and 10-8 mol/L） for 48 h, expressions of MMP-1, TIMP-1 and FN mRNA were detected by semi- quantitative RT-PCR; the level of FN in the supernatant was assayed by ELISA. [ Results ] ALD increased expres- sions of TIMP-1 and FN mRNA in a dose-dependent manner, while decreased expressions of MMP-1 significantly. Then the ratio of MMP-1/TIMP-1 was declined. The level of FN in the supernatant were increased markedly when cells were exposed to ALD （P 〈0.05）. [ Conclusion] ALD can regulate MMP-1 and TIMP-1 gene expressions and promote synthesis and secretion of FN in cultured human renal tubular epithelial ceils.