TAK1基因沉默对TNF-a诱导的滑膜细胞IL-6、IL-8表达的影响

摘要

Objective:To investigate the effects of silencing transforming growth factor-β activating kinase 1 (TAK1)on the expressions of IL-6 and IL-8 induced by TNF-α in fibroblast-like synoviocytes,and to explore the role of TAK1 in rheumatoid axthritis (RA).Methods:The synthesized TAK1 siRNA and scrambled siRNA (ScRNA) were transferred into cultured RA fibroblast-like synoviocyte line MH7A by lipofectamine.The expressions of the pro-inflammatory mediator IL-6 and IL-8 and the levels of phospho-P38(p-P38),phospho-C-Jun NH2-terminal kinase(p-JNK),phospho-extracellular signal-regulated kinase(p-ERK),phospho-p65 (p-p65) and nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor,alpha(IκBa) were examined.Results:Silencing of TAK was demonstrated in synoviocytes transfected by TAK siRNA.TAK1 silencing markedly attenuated the expression of IL-6 and IL-8 in the presence of TNT-α.TAK1 silencing inhibited the activation of p38 and JNK MAPK.TAK1 silencing also inhibited activation of nuclear factor-κB (NF-κB).Conchusion:TAK1 silencing attenuated the expression of IL-6 and IL-8 in synoviocytes induced by TNF-α via inhibiting the activation of p38,JNK MAPK and NF-κB.%目的:观察转化生长因子β激活激酶1(TAK1)基因沉默对肿瘤坏死因子a(TNF-a)诱导的滑膜细胞中促炎介质白介素-6(IL-6)和白介素-8(IL-8)表达的影响,以探讨TAK1在类风湿关节炎(RA)发病中的作用.方法:采取脂质体转染方法将TAK1特异性的小干扰RNA(siRNA)和阴性对照RNA(scRNA)导入类风湿关节炎的滑膜成纤维细胞株MH7A细胞,然后分别用20 ng/ml TNF-a刺激后,检测细胞内IL-6、IL-8 mRNA的表达和培养上清中IL-6和IL-8分泌情况以及p38、ERK、JNK、p65磷酸化的水平和抑制性蛋白IκBα的变化情况.结果:siRNA-TAK1转染72 h后滑膜细胞中TAK mRNA和蛋白表达的平均抑制率分别为75％和55％.siRNA-TAK1转染下调TNF-a诱导状态下IL-6和IL8的表达,并能抑制p38、JNK、p65磷酸化和增加IκBα水平.结论:TAK1基因沉默能抑制TNF-a诱导的滑膜细胞IL-6、IL-8表达,可能与其抑制JNK和p38MAPK的活化及NF-κB的活化有关.