丝裂原激活蛋白激酶在内毒素脂多糖诱导大鼠施万细胞一氧化氮合酶表达中的作用  

THE ROLE OF MAPK IN LPS-INDUCED iNOS EXPRESSION IN RAT SCHWANN CELLS

作　　者：沈爱国[1] 王海波[2] 秦永伟[2] 程纯[2] 牛淑琼[1] 

机构地区：[1]南通大学神经再生重点实验室 [2]南通大学医学院微生物和免疫学教研室,南通226001

出　　处：《解剖学报》2007年第6期660-664,共5页Acta Anatomica Sinica

基　　金：国家自然科学基金资助项目(30300099;30770488);江苏省自然科学基金资助项目(BK2003035);江苏省高校自然科学研究项目(KJB320114);江苏省社会发展科技指导性计划项目(BS2004526);江苏省"六大人才高峰"第二批项目

摘　　要：目的主要研究丝裂原激活蛋白激酶(MAPK)信号途径在内毒素脂多糖(LPS)诱导大鼠施万细胞(Scs)诱导型一氧化氮合酶(iNOS)基因表达和一氧化氮(NO)产生中的作用。方法先用3种MAPK的特异性抑制剂PD98059(ERK1/2)、SB202190(P38MAPK)和SP600125(JNK)以不同浓度预处理细胞1h,再用LPS作用施万细胞4h后,用RT-PCR检测细胞中iNOS mRNA、IL-6mRNA和TNF-αmRNA的表达;Western blotting观察iNOS蛋白水平的表达变化;通过测定细胞培养液中亚硝酸盐含量来观察NO的水平。结果LPS可显著激活施万细胞中MAPK信号通路诱导iNOS表达。MAPK的抑制剂预处理细胞后,可显著抑制细胞iNOS mRNA和NO的合成及IL-6mRNA和TNF-αmRNA的表达。结论MAPK信号通路参与了LPS介导的大鼠施万细胞iNOS基因表达和NO产生,通过阻断细胞内信号转导通路来减少iNOS及其他细胞因子的产生,为抑制周围神经损伤后的炎症以及免疫反应发生提供了一条新思路。Objective To explore the role of mitogen-activated protein kinase （MAPK）in lipopolysaccharide （LPS）- induced iNOS expression and NO production in rat Schwann cells by the use of inhibitors PD98059 selective for extracellular signalregulated kinase 1/2（EPK1/2）, SB202190 for P38 MAPK and SP600125 for the c-Jun NH2-terminal kinase （JNK）. Methods Schwann cells were pretreated with PD98059 （30, 50, 70μmol/L）, SB202190 （10, 20, 40μmol/L） and SP600125 （10, 30, 50μmol/L） at the indicated concentrations for 1 hour before the stimulation with LPS （10mg/L） for 4 hour. The estimation of iNOS mRNA, IL-6 mRNA and TNF-α mRNA was performed by RT-PCR; the changes of iNOS protein expression were investigated by Western blotting. The NO level was observed with measurement of nitrite in the cell culture medium. Results LPS could significantly activate MAPK signal pathway and lead to the expression of iNOS and NO production. The iNOS expression and NO production induced by LPS stimulation were significantly inhibited by the three highly specific inhibitors of MAPK. In addition, the inhibitors decreased LPS-induced the expression of IL-6 mRNA and TNF-α mRNA. Conclusion Activation of MAPK pathway is involved in iNOS expression and NO production in rat Schwann cells, and the inhibition of the signal transduction pathway can be effective to reduce the production of iNOS and NO, which may be a useful strategy against inflammatory and immune reaction after peripheral nerve injury.

关 键 词：丝裂原激活蛋白激酶 内毒素脂多糖 一氧化氮合酶 施万细胞 RT-PCR Western BLOTTING 大鼠 

分 类 号：R392.11[医药卫生—免疫学]