本文主要研究内容
作者王玉琳(2019)在《自噬对PM2.5诱导支气管上皮细胞内NLRP3炎性小体活化的调控机制研究》一文中研究指出:目的:PM2.5因粒径小,随呼吸进入体内后肺泡沉积率可达83%,还可透过肺血液屏障随血液循环到达全身,对人体健康危害极大,其中肺损伤尤为显著。众多研究表明,PM2.5可刺激巨噬细胞、支气管上皮细胞及肺泡上皮细胞释放大量的炎症因子,诱发或加重哮喘、支气管炎和肺纤维化等肺部疾病,长期反复发作的慢性炎症甚至可导致肺部肿瘤的发生。因此,炎症反应是PM2.5引起呼吸系统损害的重要致病机制之一。Nod样受体蛋白3(Nod-like receptor protein 3,NLRP3)炎症小体是机体固有免疫的重要组成部分,是系列炎症反应的核心。活化的NLRP3炎性小体可通过依赖半胱氨酸天冬氨酸酶-1(cysteine-requiring aspartate protease-1,caspase-1)的分子途径使白细胞介素1β(IL-1β)和白细胞介素18(IL-18)大量释放,刺激生成炎症介质而引发多种炎症相关性疾病。现有研究显示,自噬可通过一系列自噬相关基因(autophagy-related genes,Atg)编码的自噬相关蛋白参与细胞的多种应激反应如炎性反应,在促炎和抗炎的动态平衡中具有双向调节功能。而PM2.5诱导的细胞自噬是否可促进NLRP3炎性小体的活化而加重炎症反应还有待进一步研究。Atg5-Atg12复合物和Atg8-PE复合物是自噬囊泡形成所必不可少的,这两个复合物中的任何基因的缺失或突变都抑制自噬的发生。Atg7是Atg5-Atg12复合物形成的桥梁蛋白,并参与催化微管相关蛋白1轻链3-I(microtubule-associatedprotein 1 light chain 3-I,LC3-I)转化形成LC3-II进而和自噬囊泡紧密结合,是研究自噬调控机制的重要蛋白之一。因此,本研究以人支气管上皮细胞(16HBE)为研究对象,调控Atg7的表达来探讨自噬在PM2.5诱导NLRP3炎性小体活化中的潜在调控机制,为PM2.5相关性肺部炎症疾病的预防和治疗提供新思路和分子作用靶点。方法:(1)PM2.5分别以12.5,25,50,100,200,400μg/mL的浓度体外染毒16HBE细胞12 h,24 h和48 h,MTT法检测细胞存活率,筛选出合适浓度进行后续实验。(2)PM2.5体外染毒16HBE细胞,绿色荧光蛋白-微管相关蛋白1轻链3(adenovirus expressing GFP-LC3B fusion protein,Ad-GFP-LC3B)腺病毒转染细胞观察PM2.5诱导16HBE细胞自噬小体的形成;蛋白质印迹法(Western blot)检测自噬相关蛋白LC3、Atg7、Beclin1的表达水平。(3)通过RNA干扰/过表达技术特异性上调和下调Atg7的表达,Western blot法检测干扰和过表达前后NLRP3和caspase-1蛋白表达水平,利用酶联免疫吸附(enzyme linked immunosorbent assay,ELISA)法检测Atg7干扰前后细胞上清液中IL-1β和IL-18的含量。结果:(1)随着PM2.5浓度的增加和刺激时间的延长,细胞存活率降低,存在时间依赖效应和浓度依赖效应关系;除12.5μg/mL PM2.5染毒16HBE细胞12 h时的细胞存活率与对照组相比差异无统计学意义外(P>0.05),其他浓度组细胞存活率差异均有统计学意义(P<0.05或P<0.01)。染毒24h时,PM2.5对16HBE细胞的半数抑制浓度为227.3μg/mL。(2)PM2.5能够诱导16HBE细胞中自噬小体形成,自噬小体数目随着PM2.5浓度的增加而增多,同时自噬标志性蛋白Atg7,LC3-II和Beclin1蛋白表达水平随着PM2.5染毒浓度的增加而升高,而LC3-I蛋白表达水平降低,与对照组相比,差异具有统计学意义(P<0.05或P<0.01)。(3)不同浓度PM2.5体外孵育16HBE细胞,细胞内NLRP3、caspase-1蛋白表达水平和细胞上清液中的IL-1β、IL-18的表达水平均随PM2.5染毒浓度的增高而不同程度的上升,差异具有统计学意义(P<0.05或P<0.01)。(4)特异性下调16HBE细胞中的Atg7时,Beclin1表达水平降低44.64%;特异性上调16HBE细胞中的Atg7时,Beclin1表达水平升高51.32%,差异具有统计学意义(P<0.01);(5)特异性下调Atg7的表达水平后,PM2.5诱导的NLRP3和caspase-1蛋白表达水平和炎性因子IL-1β和IL-18分泌分水均不同程度降低;特异性上调Atg7的表达水平后,NLRP3和caspase-1蛋白表达水平和炎性因子IL-1β和IL-18分泌分水均有一定水平的升高,差异具有统计学意义(P<0.05或P<0.01)。结论:(1)PM2.5可诱导支气管上皮细胞自噬的发生;(2)PM2.5可活化支气管上皮细胞内NLRP3炎性小体,促进IL-1β和IL-18的分泌,导致机体炎症反应。(3)PM2.5诱导的自噬可通过Atg7促进NLRP3炎性小体的活化来加重机体炎症反应。
Abstract
mu de :PM2.5yin li jing xiao ,sui hu xi jin ru ti nei hou fei pao chen ji lv ke da 83%,hai ke tou guo fei xie ye bing zhang sui xie ye xun huan dao da quan shen ,dui ren ti jian kang wei hai ji da ,ji zhong fei sun shang you wei xian zhe 。zhong duo yan jiu biao ming ,PM2.5ke ci ji ju shi xi bao 、zhi qi guan shang pi xi bao ji fei pao shang pi xi bao shi fang da liang de yan zheng yin zi ,you fa huo jia chong xiao chuan 、zhi qi guan yan he fei qian wei hua deng fei bu ji bing ,chang ji fan fu fa zuo de man xing yan zheng shen zhi ke dao zhi fei bu zhong liu de fa sheng 。yin ci ,yan zheng fan ying shi PM2.5yin qi hu xi ji tong sun hai de chong yao zhi bing ji zhi zhi yi 。Nodyang shou ti dan bai 3(Nod-like receptor protein 3,NLRP3)yan zheng xiao ti shi ji ti gu you mian yi de chong yao zu cheng bu fen ,shi ji lie yan zheng fan ying de he xin 。huo hua de NLRP3yan xing xiao ti ke tong guo yi lai ban guang an suan tian dong an suan mei -1(cysteine-requiring aspartate protease-1,caspase-1)de fen zi tu jing shi bai xi bao jie su 1β(IL-1β)he bai xi bao jie su 18(IL-18)da liang shi fang ,ci ji sheng cheng yan zheng jie zhi er yin fa duo chong yan zheng xiang guan xing ji bing 。xian you yan jiu xian shi ,zi shi ke tong guo yi ji lie zi shi xiang guan ji yin (autophagy-related genes,Atg)bian ma de zi shi xiang guan dan bai can yu xi bao de duo chong ying ji fan ying ru yan xing fan ying ,zai cu yan he kang yan de dong tai ping heng zhong ju you shuang xiang diao jie gong neng 。er PM2.5you dao de xi bao zi shi shi fou ke cu jin NLRP3yan xing xiao ti de huo hua er jia chong yan zheng fan ying hai you dai jin yi bu yan jiu 。Atg5-Atg12fu ge wu he Atg8-PEfu ge wu shi zi shi nang pao xing cheng suo bi bu ke shao de ,zhe liang ge fu ge wu zhong de ren he ji yin de que shi huo tu bian dou yi zhi zi shi de fa sheng 。Atg7shi Atg5-Atg12fu ge wu xing cheng de qiao liang dan bai ,bing can yu cui hua wei guan xiang guan dan bai 1qing lian 3-I(microtubule-associatedprotein 1 light chain 3-I,LC3-I)zhuai hua xing cheng LC3-IIjin er he zi shi nang pao jin mi jie ge ,shi yan jiu zi shi diao kong ji zhi de chong yao dan bai zhi yi 。yin ci ,ben yan jiu yi ren zhi qi guan shang pi xi bao (16HBE)wei yan jiu dui xiang ,diao kong Atg7de biao da lai tan tao zi shi zai PM2.5you dao NLRP3yan xing xiao ti huo hua zhong de qian zai diao kong ji zhi ,wei PM2.5xiang guan xing fei bu yan zheng ji bing de yu fang he zhi liao di gong xin sai lu he fen zi zuo yong ba dian 。fang fa :(1)PM2.5fen bie yi 12.5,25,50,100,200,400μg/mLde nong du ti wai ran du 16HBExi bao 12 h,24 hhe 48 h,MTTfa jian ce xi bao cun huo lv ,shai shua chu ge kuo nong du jin hang hou xu shi yan 。(2)PM2.5ti wai ran du 16HBExi bao ,lu se ying guang dan bai -wei guan xiang guan dan bai 1qing lian 3(adenovirus expressing GFP-LC3B fusion protein,Ad-GFP-LC3B)xian bing du zhuai ran xi bao guan cha PM2.5you dao 16HBExi bao zi shi xiao ti de xing cheng ;dan bai zhi yin ji fa (Western blot)jian ce zi shi xiang guan dan bai LC3、Atg7、Beclin1de biao da shui ping 。(3)tong guo RNAgan rao /guo biao da ji shu te yi xing shang diao he xia diao Atg7de biao da ,Western blotfa jian ce gan rao he guo biao da qian hou NLRP3he caspase-1dan bai biao da shui ping ,li yong mei lian mian yi xi fu (enzyme linked immunosorbent assay,ELISA)fa jian ce Atg7gan rao qian hou xi bao shang qing ye zhong IL-1βhe IL-18de han liang 。jie guo :(1)sui zhao PM2.5nong du de zeng jia he ci ji shi jian de yan chang ,xi bao cun huo lv jiang di ,cun zai shi jian yi lai xiao ying he nong du yi lai xiao ying guan ji ;chu 12.5μg/mL PM2.5ran du 16HBExi bao 12 hshi de xi bao cun huo lv yu dui zhao zu xiang bi cha yi mo tong ji xue yi yi wai (P>0.05),ji ta nong du zu xi bao cun huo lv cha yi jun you tong ji xue yi yi (P<0.05huo P<0.01)。ran du 24hshi ,PM2.5dui 16HBExi bao de ban shu yi zhi nong du wei 227.3μg/mL。(2)PM2.5neng gou you dao 16HBExi bao zhong zi shi xiao ti xing cheng ,zi shi xiao ti shu mu sui zhao PM2.5nong du de zeng jia er zeng duo ,tong shi zi shi biao zhi xing dan bai Atg7,LC3-IIhe Beclin1dan bai biao da shui ping sui zhao PM2.5ran du nong du de zeng jia er sheng gao ,er LC3-Idan bai biao da shui ping jiang di ,yu dui zhao zu xiang bi ,cha yi ju you tong ji xue yi yi (P<0.05huo P<0.01)。(3)bu tong nong du PM2.5ti wai fu yo 16HBExi bao ,xi bao nei NLRP3、caspase-1dan bai biao da shui ping he xi bao shang qing ye zhong de IL-1β、IL-18de biao da shui ping jun sui PM2.5ran du nong du de zeng gao er bu tong cheng du de shang sheng ,cha yi ju you tong ji xue yi yi (P<0.05huo P<0.01)。(4)te yi xing xia diao 16HBExi bao zhong de Atg7shi ,Beclin1biao da shui ping jiang di 44.64%;te yi xing shang diao 16HBExi bao zhong de Atg7shi ,Beclin1biao da shui ping sheng gao 51.32%,cha yi ju you tong ji xue yi yi (P<0.01);(5)te yi xing xia diao Atg7de biao da shui ping hou ,PM2.5you dao de NLRP3he caspase-1dan bai biao da shui ping he yan xing yin zi IL-1βhe IL-18fen bi fen shui jun bu tong cheng du jiang di ;te yi xing shang diao Atg7de biao da shui ping hou ,NLRP3he caspase-1dan bai biao da shui ping he yan xing yin zi IL-1βhe IL-18fen bi fen shui jun you yi ding shui ping de sheng gao ,cha yi ju you tong ji xue yi yi (P<0.05huo P<0.01)。jie lun :(1)PM2.5ke you dao zhi qi guan shang pi xi bao zi shi de fa sheng ;(2)PM2.5ke huo hua zhi qi guan shang pi xi bao nei NLRP3yan xing xiao ti ,cu jin IL-1βhe IL-18de fen bi ,dao zhi ji ti yan zheng fan ying 。(3)PM2.5you dao de zi shi ke tong guo Atg7cu jin NLRP3yan xing xiao ti de huo hua lai jia chong ji ti yan zheng fan ying 。
论文参考文献
论文详细介绍
论文作者分别是来自西南医科大学的王玉琳,发表于刊物西南医科大学2019-07-16论文,是一篇关于自噬论文,炎性小体论文,西南医科大学2019-07-16论文的文章。本文可供学术参考使用,各位学者可以免费参考阅读下载,文章观点不代表本站观点,资料来自西南医科大学2019-07-16论文网站,若本站收录的文献无意侵犯了您的著作版权,请联系我们删除。
标签:自噬论文; 炎性小体论文; 西南医科大学2019-07-16论文;