發(fā)布時間：2018-05-04 19:15

  本文選題：LPS + miR-206��； 參考：《華中農(nóng)業(yè)大學》2015年碩士論文

【摘要】：Micro RNA是一種重要的基因轉(zhuǎn)錄后調(diào)節(jié)因子,在細胞發(fā)育、凋亡、分化,抗病原微生物感染及機體炎癥反應(yīng)過程中都發(fā)揮重要的調(diào)節(jié)作用。膠質(zhì)細胞激活后釋放的促炎性因子在急性或慢性腦部炎癥病程中扮演著重要角色,而有關(guān)micro RNA參與細菌脂多糖(LPS)介導(dǎo)膠質(zhì)細胞激活從而誘發(fā)炎癥反應(yīng)的調(diào)節(jié)機制尚待解析。本研究以LPS刺激人星形膠質(zhì)細胞系U251細胞誘發(fā)炎癥反應(yīng)為研究模型,從宿主micro RNA調(diào)節(jié)炎癥反應(yīng)的角度去闡述膠質(zhì)細胞誘發(fā)炎癥反應(yīng)的分子機制。具體研究內(nèi)容如下:1.LPS刺激膠質(zhì)細胞上調(diào)mi R-206的表達及其功能研究我們發(fā)現(xiàn)LPS刺激U251細胞可以顯著促進mi R-206的表達,在LPS處理的U251細胞中過表達mi R-206可以誘導(dǎo)IL-6、IL-1β和趨化因子CCL5的表達,而抑制內(nèi)源性mi R-206表達,則顯著減弱IL-6、IL-1β、CCL5和TNF-α的表達。2.Mi R-206的靶基因及其調(diào)控炎癥的作用機制研究通過生物信息學軟件預(yù)測了負調(diào)控膠質(zhì)細胞炎癥反應(yīng)的NR4A2分子可能為mi R-206的靶基因。在此基礎(chǔ)上,通過雙熒光素酶實驗、實時熒光定量和蛋白免疫印跡技術(shù)證實了mi R-206確實靶向NR4A2分子。同時,進一步揭示了mi R-206調(diào)控LPS介導(dǎo)的U251細胞炎癥反應(yīng)是通過靶向NR4A2分子和激活NF-κB信號通路來實現(xiàn)的。3.LPS調(diào)控mi R-206表達的機制研究為進一步研究LPS調(diào)控mi R-206表達的分子機制,我們研究轉(zhuǎn)錄因子在調(diào)控mi R-206表達中的作用。結(jié)果發(fā)現(xiàn)轉(zhuǎn)錄因子AP-1可以激活mi R-206的啟動子活性從而正向調(diào)控mi R-206的表達,特異性信號通路抑制劑實驗表明ERK信號通路參與了mi R-206的表達。本研究首次發(fā)現(xiàn)并證實了星形膠質(zhì)細胞中mi R-206調(diào)控LPS介導(dǎo)的炎癥反應(yīng)的分子機制,為進一步揭示腦部炎癥發(fā)生的機制提供了科學依據(jù)。
[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.
【學位授予單位】：華中農(nóng)業(yè)大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：S852.3

【參考文獻】

相關(guān)期刊論文 前1條

1 Ning Tian;Zeyuan Cao;Yan Zhang;;MiR-206 decreases brain-derived neurotrophic factor levels in a transgenic mouse model of Alzheimer's disease[J];Neuroscience Bulletin;2014年02期

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本文編號：1844298