miR-192调控NOD2信号通路在结核感染过程中的分子机制研究

Previous studies have shown that NOD2, miRNA may be molecular targets for tuberculosis infection, however, the mechanism is not clear. Our group found that the lower expression of miR-192 in patients with pulmonary tuberculosis (PTB); bioinformatics and functional experiment demonstrated that NOD2 was the target gene regulated by miR-192 in PTB. Based on previous research, we proposed " Mycobacterium tuberculosis infection activated miR-192, inducing lower expression of miR-192 and up-regulation of NOD2 expression, overexpression of NOD2 induced excessive NF-κB activation, caused to excessive inflammatory injury in the tuberculosis infection ". We will explore the mechanism that excessive activation of NOD2 signaling pathway mediated by miR-192 in the tuberculosis infection from the cellular and overall perspective, using RT-PCR, MSP, siRNA transfection, Western blotting techniques. This study will provide a new direction to find potential molecular targets for diagnosis and treatment of tuberculosis.

已有研究表明NOD2样受体和miRNA可能参与调控结核感染过程，但具体调控机制尚不清楚。课题组前期发现miR-192在新疆汉族肺结核患者中表达下调显著，提示其可能参与结核感染的分子调控过程；进一步的预实验证实NOD2是miR-192 调控的靶基因。基于课题组前期研究，我们提出“结核分枝杆菌感染下调miR-192 表达，下调的miR-192导致其靶基因NOD2样受体高表达，后者通过调控NF-κB通路异常激活，致过度炎症损伤，参与调控结核感染的过程”。本研究拟用RT-PCR、MSP、siRNA 转染、Western blotting、原位杂交等技术，从细胞和整体水平较全面的探讨miR-192调控NOD2，异常激活N F-KB信号通路，参与结核感染炎性反应的分子机制。本研究将为进一步找寻潜在的结核诊疗分子靶点提供新的方向。

由结核分枝杆菌引起的结核病是严重危害人类健康的重大传染病。该研究采用qRT-PCR和Western blot检测miRNA-192、NOD2和NF-κB的分子以及蛋白水平的表达，同时通过上调和下调miRNA-192观察NOD2以及NF-κB分子的表达水平，抑制NOD2表达水平观察NF-κB分子的表达水平，采用ELISA检测相关细胞因子（IL-6、IL-10、IL-12、IL-17、TNF-α、IFN-γ）的表达水平。该研究的结果显示，活动性肺结核病人均表达miRNA-192、NOD2和NF-κB，较健康对照组是升高的。调控miRNA-192和NOD2的表达水平，可以发现，下游NF-κB信号通路也是升高的。因此，该研究发现当结核分枝杆菌感染宿主时，miRNA-192的表达是升高的，上调的NOD2调控NF-κB信号通路参与结核分枝杆菌的感染过程。