【摘要】 目的:观察过氧化物酶体增殖物激活受体γ(PPARγ)激动剂15d-PGJ2对干扰素-γ(IFN-γ)和肿瘤坏死因子α(TNF-α)诱导的人近端肾小管上皮细胞(HK-2)CD40和RANTES表达的影响。方法:体外培养人近端肾小管上皮细胞株,分组如下:(1)正常对照组;(2)IFN-γ(50μg/ml)组;(3)TNF-α(10ng/ml)组;(4)IFN-γ(50μg/ml)+TNF-α(10ng/ml)组;(5)IFN-γ(50μg/ml)+TNF-α(10ng/ml)分别加1、3、5μmol/L15d-PGJ2组;(6)IFN-γ+TNF-α刺激+15d-PGJ2(5μmol/L)+GW9662(PPARγ特异拮抗剂)1μmol/L组。GW9662和15d-PGJ2分别在IFN-γ和TNF-α刺激前3和2小时加入。分别采用RT-PCR、流式细胞仪(FACS)和酶联免疫法(ELISA)检测CD40和RANTES基因和蛋白的表达水平。结果:正常HK-2细胞中,CD40、RANTES有基础水平表达。IFN-γ能显著上调HK-2细胞CD40蛋白的表达;TNF-α单独刺激对CD40表达无显著影响,但能增强IFN-γ的刺激效应。IFN-γ+TNF-α显著增加HK-2细胞RANTES的表达和分泌。15d-PGJ2呈剂量依赖式在基因和蛋白水平显著抑制IFN-γ+TNF-α诱导的CD40和RANTES的表达。加入PPARγ特异拮抗剂GW9662后,能够部分逆转15d-PGJ2对CD40和RANTES表达的抑制效应,但并不能完全阻断其作用。结论:15d-PGJ2部分通过PPARγ介导的信号途径参与抑制IFN-γ+TNF-α诱导的人近端肾小管上皮细胞CD40和RANTES的表达,从而在肾脏局部发挥免疫调节和抗炎作用。更多还原

【Abstract】 Objective:To observe the effect of PPARγ agonists 15d-PGJ₂ on the expression of CD40 and RANTES in cultured proximal tubule cells（HK-2） induced by IFN-γ and TNF-α. Methods:HK-2 cells were cultured in DMEM/F12 with 10% fetal bovine serum in vitro and were divided into following groups: IFN-γ（50 μg/ml） group, TNF-α（10 ng/ml） group,IFN-γ（50 μg/ml）+TNF-α（10 ng/ml） group, IFN-γ（50 μg/ml）+TNF-α（10 ng/ml） with 1,3,5 μmol/L 15d-PGJ₂ groups and IFN-γ（50 μg/ml）+TNF-α（10 ng/ml） with 15d-PGJ₂（5 μmol/L） and GW9662（1 μmol/L） group. The expression of CD40 mRNA and protein were measured by RT-PCR and flow cytometry（FACS） respectively. The expression of RANTES mRNA and protein were measured by RT-PCR and ELISA respectively.Results:HK-2 cells expressed low levels of CD40 and RANTES. Activation of HK-2 cells by IFN-γ resulted in an enhanced expression of CD40; the present of TNF-α alone did not result in significant expression of CD40, but simultaneous activation of HK-2 cells by TNF-α and IFN-γ result in strong synergistic effect on the expression of CD40 Combinations of TNF-α together with IFN-γ resulted in up-regulated RANTES mRNA and strong induction of RANTES production. The PPARγ agonists 15-deoxy-12,14-prostaglandin J₂（15d-PGJ₂） significantly blocked CD40 and RANTES expression in HK-2 cell line induced by IFN-γ plus TNF-α. GW9662 partly abrogated the inhibition of CD40 and RANTES induced by 15d-PGJ₂.Conclusion:15d-PGJ₂ decreased CD40 and RANTES expression induced with IFN-γ plus TNF-α in HK-2 cells,and these immune modulation and anti-inflammation effects were partially mediated by PPAR-dependent pathways.更多还原