MiR-206调控LPS介导胶质细胞炎症反应的机制研究

发布时间：2018-05-04 19:15

本文选题：LPS + miR-206　；参考：《华中农业大学》2015年硕士论文

【摘要】：Micro RNA是一种重要的基因转录后调节因子,在细胞发育、凋亡、分化,抗病原微生物感染及机体炎症反应过程中都发挥重要的调节作用。胶质细胞激活后释放的促炎性因子在急性或慢性脑部炎症病程中扮演着重要角色,而有关micro RNA参与细菌脂多糖(LPS)介导胶质细胞激活从而诱发炎症反应的调节机制尚待解析。本研究以LPS刺激人星形胶质细胞系U251细胞诱发炎症反应为研究模型,从宿主micro RNA调节炎症反应的角度去阐述胶质细胞诱发炎症反应的分子机制。具体研究内容如下:1.LPS刺激胶质细胞上调mi R-206的表达及其功能研究我们发现LPS刺激U251细胞可以显著促进mi R-206的表达,在LPS处理的U251细胞中过表达mi R-206可以诱导IL-6、IL-1β和趋化因子CCL5的表达,而抑制内源性mi R-206表达,则显著减弱IL-6、IL-1β、CCL5和TNF-α的表达。2.Mi R-206的靶基因及其调控炎症的作用机制研究通过生物信息学软件预测了负调控胶质细胞炎症反应的NR4A2分子可能为mi R-206的靶基因。在此基础上,通过双荧光素酶实验、实时荧光定量和蛋白免疫印迹技术证实了mi R-206确实靶向NR4A2分子。同时,进一步揭示了mi R-206调控LPS介导的U251细胞炎症反应是通过靶向NR4A2分子和激活NF-κB信号通路来实现的。3.LPS调控mi R-206表达的机制研究为进一步研究LPS调控mi R-206表达的分子机制,我们研究转录因子在调控mi R-206表达中的作用。结果发现转录因子AP-1可以激活mi R-206的启动子活性从而正向调控mi R-206的表达,特异性信号通路抑制剂实验表明ERK信号通路参与了mi R-206的表达。本研究首次发现并证实了星形胶质细胞中mi R-206调控LPS介导的炎症反应的分子机制,为进一步揭示脑部炎症发生的机制提供了科学依据。
[Abstract]:Micro RNA is an important gene posttranscriptional regulator, which plays an important role in cell development, apoptosis, differentiation, anti-pathogenic microorganism infection and inflammatory reaction. The pro-inflammatory factors released after the activation of glial cells play an important role in the course of acute or chronic brain inflammation. However, the regulatory mechanism of micro RNA involved in the activation of glial cells mediated by bacterial lipopolysaccharide (LPS) and induced inflammation has yet to be elucidated. In this study, LPS stimulated human astrocytes U251 cells to induce inflammatory response as a model, from the host micro RNA to regulate the inflammatory response to explain the molecular mechanism of glial cells induced inflammation. The specific research contents are as follows: 1. LPS-stimulated glial cells up-regulate the expression of mi R-206 and its function. We found that LPS stimulated U251 cells can significantly promote the expression of mi R-206. Overexpression of mi R-206 in U251 cells treated with LPS could induce the expression of IL-6G IL-1 尾 and chemokine CCL5, but inhibit the expression of endogenous mi R-206. 2. The target gene of Mi R-206 and its mechanism of regulating inflammation; the NR4A2 molecule that negatively regulates the inflammatory response of glial cells was predicted to be the target gene of mi R-206 by bioinformatics software. On the basis of this, it was confirmed by double luciferase experiment, real-time fluorescence quantitative analysis and Western blotting that mi R-206 really targeted NR4A2 molecule. At the same time, it was further revealed that the mechanism of mi R-206 regulating LPS mediated inflammation in U251 cells was realized by targeting NR4A2 molecules and activating NF- 魏 B signaling pathway. 3. The mechanism of LPS regulating the expression of mi R-206 was further studied for the further study of the molecular mechanism of LPS regulating the expression of R-206. We studied the role of transcription factors in regulating the expression of mi R-206. The results showed that the transcription factor AP-1 could activate the promoter activity of miR-206 and positively regulate the expression of miR-206. The specific signaling pathway inhibitor experiment showed that the ERK signaling pathway was involved in the expression of miR-206. In this study, the molecular mechanism of mi R-206 regulating the inflammatory response mediated by LPS in astrocytes was first discovered and confirmed, which provides scientific basis for further revealing the mechanism of inflammation in the brain.
【学位授予单位】：华中农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S852.3

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