中文摘要：

目的研究微小RNA-146a（miR-146a）对类风湿关节炎（RA）患者滑膜成纤维细胞增殖及细胞因子分泌的影响。方法体外分离培养RA患者滑膜成纤维细胞，脂质体转染化学合成的miR-146a，^3H掺入法检测滑膜成纤维细胞增殖，酶联免疫吸附试验（ELISA）法检测细胞上清白细胞介素（IL）-8及IL-6水平。实时定量聚合酶链反应（PCR）检测滑膜成纤维细胞中miR-146a靶分子肿瘤坏死因子受体相关因子6（TRAF6）、IL-受体相关激酶（IRAK1）的mRNA水平。应用独立样本t检验进行统计学分析。结果与阴性对照小RNA相比，miR-146a转染后的滑膜成纤维细胞增殖能力明显下降（2015±545与8799±1922，P〈0．01），IL-8及IL-6分泌受到明显抑制[（153±49）pg/ml与（311±123）pg／ml，P〈0．01和（295±95）pg／ml与（459±126）pg／ml，P〈0．05]。定量PCR检测IRAK1的mRNA水平显示，miR-146a转染可明显下调滑膜成纤维细胞IRAK1的表达（0．28±0．07与1，P〈0．01）。结论miR-146a可能通过下调IRAK1表达，进而抑制滑膜成纤维细胞增殖及IL-8、IL-6等炎性细胞因子分泌，从而发挥抑制RA滑膜炎症的作用。

英文摘要：

Objective To explore the effect of miR-146a on the proliferation and the IL-8 and IL-6 secretion of rheumatoid arthritis synovial fibroblasts （RASFs）. Methods miR-146a was transfected into cult- ured synovial cells from RA patients in vitro by Lipofectamine 2000. Fibroblast proliferation was assayed by ^3H-TdR incorporation test IL-6 and IL-8 in the cell culture supernatant were detected by ELISA kit mRNA expression of TRAF6 and IRAK1, the possible targets of miR-146a were detected by real-time PCR. All data was analyzed by independent samples t-test. Results It was shown that the proliferation of RASFs transfeeted with miR-146a was markedly downregulated compared to those transfected with the negative control （2015± 545 vs 8799±1922, P〈0.01 ）. Furthermore, the levels of IL-8 and IL-6 secretion were significantly lower in RASFs transfected with miR-146a than those with the negative control [ （153±49） pg/ml vs （311±123 ） pg/ml, P〈0.01 and （295±95） pg/ml vs （459±126） pg/ml, P〈0.05]. It was shown that the mRNA expression of IRAKI was downregnlated significantly by miR-146a transfeetion in RASFs （0.28±0.07 vs 1, P〈0.01）. Conclusion miR-146a could inhibit the proliferation and the secretion of IL-8 and IL-6 of RA synovial fibroblasts and IRAK1 may be the main target of miR-146a resulting in the inhibitory effect in RASFs.