TGF-β_1对肾小管上皮细胞炎症相关趋化因子表达的影响

Effects of TGF-β_1 on expression of inflammation-related chemokines in renal tubular epithelial cells

目的观察转化生长因子β1（TGF-β1）对肾小管上皮细胞炎症相关趋化因子表达的影响，探讨其在肾间质炎症进展中的作用。方法体外培养人近端肾小管上皮细胞系（HK-2），用不同浓度（0～10ng／mL）TGF—β1刺激24h或用5ng／mLTGF—β1刺激不同时间（0～48h），荧光定量PCR技术和ELISA方法分别检测趋化因子单核细胞趋化蛋白-1（MCP-1）、白介素-8（IL-8）、正常T细胞活化后表达和分泌调节蛋白（RANTES）的mRNA和蛋白表达的变化。结果TGF—β1能诱导HK-2细胞MCP—1．IL-8、RANTES的表达上调，且呈剂量和时间依赖效应。2ng／mLTGF—β1作用24h即可诱导MCP—1和IL-8mRNA明显升高，5ng／mLTGF—β1作用时达高峰。MCP—1和IL-8蛋白分泌分别于刺激后36h和24h达高峰。2ng／mL和5ng／mLTGF—β1均可诱导RANTESmRNA明显升高，2h时RANTESmRNA表达开始升高，24h达高峰；RANTES蛋白基础分泌水平极低，TGF—β1作用24h时RANTES蛋白分泌开始升高，36h达高峰。结论TGF—β1诱导能明显上调趋化因子MCP-1、IL-8和RANTES的mRNA表达和蛋白分泌。因此，有效干预TGF—β1诱导的趋化因子的表达可能成为减轻肾间质炎症的途径之一。

Objective To observe the effects of transforming growth factor-β1 （TGF-β1） on the expression of inflammation- related chemokines in renal tubular epithelial cells, and investigate its roles in the progress of renal interstitial inflammation. Methods Human proximal renal tubular epithelial cells （HK-2） were cultured in vitro and stimulated by TGF-β1 with different concentrations （0-10 ng/mL） for 24 h or by 5 ng/mL TGF-β1 for different time （0-48 h）. The expression of chemokines such as monocyte chemoattractant protein-1 （MCP-1） , interleukin-8 （IL-8） and RANTES were detected by Real-time PCR and ELISA. Results TGF-β1 induced the expression of MCP-1, IL-8 and RANTES in HK-2 cells in a dose- and time-dependent manner. After being stimulated by 2 ng/mL TGF-131 for 24 h, the expression of MCP-1 and IL-8 mRNA significantly increased, and that reached the peak levels with 5 ng/mL TGF-β1. The excretion of MCP-1 protein and IL-8 protein reached the peak levels after being stimulated for 36 h or 24 h, respectively. Both 2 ng/mL and 5 ng/mL TGF- β1 induced the expression of RANTES mRNA. RANTES mRNA expression began to elevate at 2 h and reached the peak at 24 h. The RANTES protein excretion was extremely low at baseline, began to elevate at 24 h and reached the peak at 36 h after being stimulated by TGF-β1. Conclusion TGF-β1 significantly up-regulates the mRNA expression and protein excretion of chemokines such as MCP-1, IL-8 and RANTES. Effective intervention on the expression of chemokines by TGF- β1 may become a potential pathway to prevent renal interstitial inflammation.