miR-146a对登革病毒诱导的炎性因子的负调控及机制研究

miR-146 a downregulates inflammatory cytokines induced by dengue virus through impairing the activation of MAPK and NF-κB signaling

目的探讨miR-146a对登革病毒感染过程中炎性因子产生的影响及其调控机制。方法建立过表达miR-146a的THP-1细胞模型,以Real-time PCR检测登革病毒诱导的炎性因子TNFα、IL-6、IL-12和IL-8的mRNA表达水平;采用Western blot方法检测细胞丝裂原蛋白激酶(MAPK)信号通路在登革病毒感染后不同时间点的激活情况;通过免疫荧光检测登革病毒感染后核因子κΒ(NF-κB)的核转位情况。结果 miR-146a过表达细胞在登革病毒感染后所表达的TNFα、IL-6、IL-12和IL-8等炎性因子mRNA水平明显下调;miR-146a过表达可明显抑制MAPK、NF-κB信号通路的激活。结论 miR-146a通过抑制登革病毒诱导的MAPK、NF-κB信号通路激活从而调控炎性因子产生。

Objective To investigate whether miR-146a plays a role in the induction of inflammatory cytokines by dengue virus （DENV）. Methods THP-1 cells were transfected with miR-146a mimic, followed by DENV2 infection. The expression levels of inflammatory cytokines,including TNFα,IL-6,IL-12 and IL-8 were detected by Real-time PCR. Activation of MAPK signal pathway at 12 or 24 h post DENV2 infection was detected by Western blot.Nuclear translocation of NF-κB at 24 h post DENV2 infection was detected by indirect immunnfluorescence microscopy. Results The expression levels of inflammatory cytokines were significantly reduced in miR-146a-overexpressing cells. Overexpression of miR-146a significantly reduced the activation of MAPK and the nuclear translocation of NF-κB. Conclusion miR-146a downregulated the expression of DENV-induced inflammatory cytokines by impairing the activation of MAPK and NF-κB signal pathways.