TAK1基因沉默对TNF-a诱导的滑膜细胞IL-6、IL-8表达的影响

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IL-8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。

Effects of TAK gene silencing on the expressions of IL-6 and IL-8 induced by TNF-α in fibroblast-like synoviocytes

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 arthritis (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 TNF-α. TAK1 silencing inhibited the activation of p38 and JNK MAPK. TAK1 silencing also inhibited activation of nuclear factor-κB (NF-κB).Conclusion: 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.