PTS2對LPS引起的RAW264.7細(xì)胞中iNOS蛋白表達的影響及其機理研究
發(fā)布時間：2019-07-05 11:45
【摘要】： LPS是革蘭氏陰性菌細(xì)胞壁的主要成分。用LPS處理細(xì)胞或動物能夠引起類似于膿毒性休克的炎癥反應(yīng)。膿毒性休克能引起嚴(yán)重的循環(huán)系統(tǒng)障礙,致死率高達30—90%且治療無效。促炎細(xì)胞主要是指活化的巨噬細(xì)胞,它們在炎癥過程中能夠產(chǎn)生大量的細(xì)胞因子和促炎分子,包括血小板活化因子、前列腺素、酶和類似NO的自由基分子等。這些分子能夠在細(xì)胞和分子水平上引起膿毒癥的病理生理反應(yīng)。在大多數(shù)炎癥介質(zhì)中,NO是內(nèi)毒素血癥和炎癥反應(yīng)的重要調(diào)節(jié)分子。NO能夠與超氧陰離子(O~(2-))迅速反應(yīng)生成過氧化亞硝酸鹽(ONOO~-)。過氧化亞硝酸鹽(ONOO~-)能夠?qū)е翫NA破壞、低密度脂蛋白(LDL)氧化并使其酪氨酸發(fā)生硝化作用。NO在炎癥發(fā)生的各個階段都能起到調(diào)節(jié)作用,尤其是在炎癥發(fā)生早期炎癥細(xì)胞遷移到炎癥部位的過程中。在炎癥發(fā)生過程中,過量的NO主要由誘導(dǎo)型一氧化氮合酶(iNOS)催化產(chǎn)生。LPS刺激巨噬細(xì)胞能夠上調(diào)胞內(nèi)iNOS的蛋白水平。許多能夠抑制iNOS表達或iNOS酶活的化合物都具有抗炎活性。在包括巨噬細(xì)胞在內(nèi)的多種細(xì)胞中,LPS能夠刺激Toll樣受體4(TLR-4)從而活化NF-κB。NF-κB作為重要的轉(zhuǎn)錄因子參與iNOS的基因表達。另外一個參與LPS刺激下iNOS表達調(diào)控的轉(zhuǎn)錄因子STAT1(the signal transducerand activator of transcription 1)是通過JAK-STAT通路被活化。LPS也可以通過活化巨噬細(xì)胞內(nèi)MAPKs信號通路來增強iNOS基因表達。 PTS2(2,2'-二吡啶N-氧化物二硫)屬于巰氧吡啶的衍生物(CASnumber:3696-28-4),通常被用于抗細(xì)菌和抗真菌藥物。PTO(Pyrithione)是PTS2的單體,能夠抑制真菌、酵母菌、霉菌、細(xì)菌的生長,被廣泛應(yīng)用于美容及洗發(fā)用品的添加成分。之前,我們的研究證明了PTS2能夠通過活化MAPKs信號通路來誘導(dǎo)HeLa細(xì)胞凋亡。最近我們發(fā)現(xiàn),在鼠巨噬細(xì)胞RAW264.7細(xì)胞中PTS2能夠劑量依賴性地抑制LPS刺激下的iNOS的蛋白表達及NO的釋放。在其分子機制的研究過程中,我們發(fā)現(xiàn)PTS2能夠降低LPS刺激下轉(zhuǎn)錄因子STAT1的磷酸化活化而不影響MAPKs和NF-κB信號通路。所以我們得出結(jié)論,在鼠巨噬細(xì)胞RAW264.7細(xì)胞中PTS2能夠通過影響LPS刺激下STAT1的激活從而抑制iNOS蛋白表達及NO釋放,發(fā)揮抗炎作用。
[Abstract]:LPS is the main component of the cell wall of Gram-negative bacteria. LPS treatment of cells or animals can cause inflammatory reactions similar to septic shock. Septic shock can cause serious circulatory system disorders, the fatality rate is as high as 30% and 90%, and the treatment is ineffective. Pro-inflammatory cells mainly refer to activated macrophages, which can produce a large number of cytokines and pro-inflammatory molecules, including platelet activating factor, prostaglandin, enzyme and NO-like free radical molecules. These molecules can cause pathophysiological responses to sepsis at the cellular and molecular levels. In most inflammatory mediators, NO is an important regulator of endotoxemia and inflammatory response. No can react rapidly with hyperoxia anion (O2 -) to form nitrous peroxide (ONOO~-). Nitrate peroxide (ONOO~-) can lead to the destruction of DNA, the oxidation of low density lipoprotein (LDL) and the nitrification of its tyrosine. No can play a regulatory role in all stages of inflammation, especially in the process of migration of inflammatory cells to inflammatory sites in the early stage of inflammation. In the process of inflammation, excessive NO is mainly catalyzed by (iNOS), which stimulates macrophages to up-regulate the protein level of intracellular iNOS. Many compounds that can inhibit iNOS expression or iNOS enzyme activity have anti-inflammatory activity. In a variety of cells, including macrophages, LPS can stimulate Toll-like receptor 4 (TLR-4) and activate NF- 魏 B.NF-魏 B as an important transcription factor to participate in the gene expression of iNOS. Another transcription factor STAT1 (the signal transducerand activator of transcription 1, which is involved in the regulation of iNOS expression stimulated by LPS, is activated through JAK-STAT pathway. LPs can also enhance iNOS gene expression by activating MAPKs signaling pathway in macrophages. PTS2 (2, 2 dipyridine N-oxide disulfide) is a derivative of mercaptopyridine (CASnumber:3696-28-4), which is usually used as an antibacterial and antifungal drug. PTO (Pyrithione) is a monomer of PTS2, which can inhibit the growth of fungi, yeast, mold and bacteria, and is widely used in beauty and shampoo products. Previous studies have shown that PTS2 can induce apoptosis of HeLa cells by activating MAPKs signaling pathway. Recently, we have found that PTS2 can inhibit the protein expression and NO release of iNOS stimulated by LPS in mouse macrophage RAW264.7 cells in a dose-dependent manner. In the course of studying its molecular mechanism, we found that PTS2 could decrease the phosphorylation and activation of transcription factor STAT1 stimulated by LPS without affecting MAPKs and NF- kappa B signaling pathways. Therefore, we concluded that PTS2 in mouse macrophage RAW264.7 cells can inhibit the expression of iNOS protein and NO release by affecting the activation of STAT1 stimulated by LPS, and play an anti-inflammatory role.
【學(xué)位授予單位】：南京師范大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2008
【分類號】：R378
本文編號：2510497
[Abstract]:LPS is the main component of the cell wall of Gram-negative bacteria. LPS treatment of cells or animals can cause inflammatory reactions similar to septic shock. Septic shock can cause serious circulatory system disorders, the fatality rate is as high as 30% and 90%, and the treatment is ineffective. Pro-inflammatory cells mainly refer to activated macrophages, which can produce a large number of cytokines and pro-inflammatory molecules, including platelet activating factor, prostaglandin, enzyme and NO-like free radical molecules. These molecules can cause pathophysiological responses to sepsis at the cellular and molecular levels. In most inflammatory mediators, NO is an important regulator of endotoxemia and inflammatory response. No can react rapidly with hyperoxia anion (O2 -) to form nitrous peroxide (ONOO~-). Nitrate peroxide (ONOO~-) can lead to the destruction of DNA, the oxidation of low density lipoprotein (LDL) and the nitrification of its tyrosine. No can play a regulatory role in all stages of inflammation, especially in the process of migration of inflammatory cells to inflammatory sites in the early stage of inflammation. In the process of inflammation, excessive NO is mainly catalyzed by (iNOS), which stimulates macrophages to up-regulate the protein level of intracellular iNOS. Many compounds that can inhibit iNOS expression or iNOS enzyme activity have anti-inflammatory activity. In a variety of cells, including macrophages, LPS can stimulate Toll-like receptor 4 (TLR-4) and activate NF- 魏 B.NF-魏 B as an important transcription factor to participate in the gene expression of iNOS. Another transcription factor STAT1 (the signal transducerand activator of transcription 1, which is involved in the regulation of iNOS expression stimulated by LPS, is activated through JAK-STAT pathway. LPs can also enhance iNOS gene expression by activating MAPKs signaling pathway in macrophages. PTS2 (2, 2 dipyridine N-oxide disulfide) is a derivative of mercaptopyridine (CASnumber:3696-28-4), which is usually used as an antibacterial and antifungal drug. PTO (Pyrithione) is a monomer of PTS2, which can inhibit the growth of fungi, yeast, mold and bacteria, and is widely used in beauty and shampoo products. Previous studies have shown that PTS2 can induce apoptosis of HeLa cells by activating MAPKs signaling pathway. Recently, we have found that PTS2 can inhibit the protein expression and NO release of iNOS stimulated by LPS in mouse macrophage RAW264.7 cells in a dose-dependent manner. In the course of studying its molecular mechanism, we found that PTS2 could decrease the phosphorylation and activation of transcription factor STAT1 stimulated by LPS without affecting MAPKs and NF- kappa B signaling pathways. Therefore, we concluded that PTS2 in mouse macrophage RAW264.7 cells can inhibit the expression of iNOS protein and NO release by affecting the activation of STAT1 stimulated by LPS, and play an anti-inflammatory role.
【學(xué)位授予單位】：南京師范大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2008
【分類號】：R378
【引證文獻】
相關(guān)碩士學(xué)位論文 前1條
1 肖楠;乙酸乙酯抑制小鼠實驗性急性肝衰竭及其作用機制的研究[D];河北大學(xué);2011年
，本文編號：2510497
本文鏈接：http://sikaile.net/yixuelunwen/shiyanyixue/2510497.html
最近更新
教材專著
