ERK1/2通过调控NADPH氧化酶和线粒体分裂在结肠炎中的作用  

The role of ERK1/2 in colitis through regulation of NADPH oxidase and mitochondrial fission

作　　者：翟晓明 谭嗣伟[1] 易玉君 刘慧玲[1] 郭佳翔 吴淑云 陶金[1] Zhai Xiaoming;Tan Siwei;Yi Yujun;Liu Huiling;Guo Jiaxiang;Wu Shuyun;Tao Jin(Department of Gastroenterology,the Third Affiliated Hospital of Sun Yat-sen University,Guangzhou 510630,China)

机构地区：[1]中山大学附属第三医院消化内科,广州510630

出　　处：《新医学》2023年第3期197-204,共8页Journal of New Medicine

基　　金：国家自然科学青年科学基金项目(81800458);国家自然科学基金面上项目(82170569)。

摘　　要：目的研究细胞外信号调节激酶1和2(ERK1/2)通过调控NADPH氧化酶(Nox)和线粒体分裂在结肠炎中的作用。方法3%葡聚糖硫酸钠(DSS)诱导小鼠急性结肠炎。将30只C57BL/6J小鼠用随机数表法分为6组:Control组、3%DSS组、1%二甲亚砜(DMSO)组、ERK1/2抑制剂(PD98059)组、3%DSS+1%DMSO组、3%DSS+PD98059组,每组5只。评估Control组和3%DSS组小鼠体重变化、结肠长度改变、疾病活动指数和结肠组织病理学改变,检测小鼠结肠黏膜ERK1/2、磷酸化(p)-ERK1/2、Nox1和Nox2表达水平。1%DMSO组、3%DSS+1%DMSO组给予腹腔注射1%DMSO;PD98059组、3%DSS+PD98059组小鼠给予腹腔注射PD98059。评估4组小鼠结肠组织病理学改变,检测Nox1、Nox2、动力相关蛋白1(DRP1)、p-DRP1-S616和p-DRP1-S637等线粒体分裂相关蛋白表达水平的改变。透射电镜观察Control组和3%DSS组小鼠结肠上皮细胞线粒体分裂情况。免疫荧光双染分析2组小鼠结肠黏膜中Nox2与线粒体外膜转位酶TOM复合体(TOMM20)共定位情况。分析2组小鼠结肠黏膜DRP1与Nox2 mRNA相对表达量的相关性。结果与Control组相比,3%DSS组小鼠体重下降、结肠长度缩短、疾病活动指数增加和结肠组织病理学评分升高,结肠黏膜p-ERK1/2、Nox1和Nox2表达增加(P均<0.05)。结肠炎小鼠结肠上皮细胞中的线粒体分裂增加,结肠黏膜的DRP1和Nox2共定位增加,两者mRNA相对表达呈正相关(r=0.678,P<0.05)。ERK1/2抑制剂PD98059改善结肠炎小鼠结肠组织病理学变化,并且下调结肠黏膜Nox1、Nox2、DRP1、p-DRP1-S616的表达。结论抑制ERK1/2可能通过减轻Nox表达和线粒体分裂,改善结肠炎。Objective To investigate the role of extracellular signal regulated kinase 1/2(ERK1/2)in colitis through the regulation of NADPH oxidase and mitochondrial fission.Methods Mice models of acute colitis were induced by 3%dextran sulfate sodium(DSS).Thirty C57BL/6J mice were randomly divided into six groups by random number table method:control group,3%DSS group,1%dimethyl sulfoxide(DMSO)group,ERK1/2 inhibitor(PD98059)group,3%DSS+1%DMSO group and 3%DSS+PD98059 group,with five mice in each group.The changes of body weight,colonic length,disease activity index and colonic histopathological changes of mice in the control and 3%DSS groups were evaluated,and the expression levels of ERK1/2,p-ERK1/2,Nicotinamide adenine dinucleotide phosphate oxidase 1(Nox1)and Nox2 in colonic mucosa of mice were detected.Mice in 1%DMSO and 3%DSS+1%DMSO groups were intraperitoneally injected with 1%DMSO.Mice in the PD98059 and 3%DSS+PD98059 groups were intraperitoneally injected with PD98059.The colonic histopathological changes were evaluated among four groups,and the expression levels of Nox1,Nox2,Dynamin related protein 1(DRP1),p-DRP1-S616 and p-DRP1-S637 mitochondrial fission related proteins were detected.Mitochondrial fission of colonic epithelial cells in the control and 3%DSS groups was observed by transmission electron microscopy.The co-localization of Nox2 and mitochondrial outer membrane translocator enzyme TOM complex(TOMM20)in colonic mucosa of mice in two groups was analyzed by double-immunofluorescence staining.The correlation between relative expression levels of DRP1 and Nox2 mRNA in mouse colonic mucosa was analyzed in two groups.Results Compared with the control group,mice in the 3%DSS group exhibited body weight loss,shortened colonic length,increased disease activity index and increased colonic histopathological score.The expression levels of p-ERK1/2,Nox1,Nox2 in colonic mucosa of mice were significantly up-regulated in the 3%DSS group(all P<0.05).In mice with colitis,mitochondrial fission in colonic epithelial cells

关 键 词：溃疡性结肠炎 细胞外信号调节激酶1和2 NADPH氧化酶 线粒体分裂 

分 类 号：R574.62[医药卫生—消化系统]