补体片段C3a及其受体在纳米二氧化硅致肺损伤中水平变化  

Changes of complement fragment C3a and its receptor in lung injury induced by silica nanoparticles

作　　者：周思凡 王周健 高磊 段元晟 陈睦跃 张家祥 朱启星 ZHOU Sifan;WANG Zhoujian;GAO Lei;DUAN Yuansheng;CHEN Muyue;ZHANG Jiaxiang;ZHU Qixing(Department of Occupational and Environmental Health,School of Public Health,Anhui Medical University,Hefei,Anhui 230032,China)

机构地区：[1]安徽医科大学公共卫生学院职业卫生与环境卫生学系,安徽合肥230032

出　　处：《环境与职业医学》2023年第8期877-883,共7页Journal of Environmental and Occupational Medicine

基　　金：安徽医科大学研究生科研与实践创新项目(YJS20230045)。

摘　　要：[背景]纳米二氧化硅(SiNPs)通过呼吸道、消化道和皮肤等进入人体,引起机体损伤,肺脏是主要受损器官之一。[目的]观察经呼吸道暴露SiNPs小鼠肺脏中补体活化片段C3a及其受体C3aR的表达情况,探讨C3a/C3aR是否参与SiNPs暴露致小鼠肺损伤。[方法]透射电子显微镜检测SiNPs(粒径5~20 nm)超微结构,纳米粒度仪测定SiNPs流体动力学直径和表面Zeta电位。88只SPF级C57BL/6J小鼠进行随机化分组:空白对照组小鼠14只,不予以任何处理;溶剂对照组小鼠14只,气管滴注50μL生理盐水;低剂量组、中剂量组、高剂量组小鼠各20只,按体重分别滴注7、21、35 mg·kg^(−1)SiNPs悬液50μL,每3 d暴露一次,共5次。在暴露结束后第1天(模型1天组)和第15天(模型15天组)麻醉小鼠,抽取支气管肺泡灌洗液(BALF)后处死小鼠,留取肺脏组织。通过HE染色观察肺组织形态学改变,酶联免疫吸附试验检测BALF中C3a表达量,免疫组化法观察肺组织中C3a、C3aR沉积情况,蛋白免疫印迹法检测C3aR蛋白表达水平,通过免疫荧光法对肺组织中C3a与C3aR进行定位以及半定量检测。[结果]SiNPs在生理盐水中会发生团聚,流体动力学直径为(185.60±7.39)nm,Zeta电位绝对值为(43.33±0.76)mV。模型1天组和15天组小鼠状态良好,模型1天组中剂量组小鼠因操作原因导致死亡2只,解剖发现肺组织淤血,存在肺气肿,气管完整。其他剂量组小鼠无死亡。HE染色结果显示,SiNPs暴露小鼠肺部产生病理损伤,表现为肺泡壁增厚、炎性细胞浸润,随着剂量的升高病理损伤越严重,模型15天组较1天组稍有缓解,但仍存在病理改变。酶联免疫吸附试验结果显示:C3a在空白对照组和溶剂对照组表达量无差异(P>0.05);与溶剂对照组相比,中剂量组和高剂量组表达均明显升高,差异有统计学意义(P<0.05)。免疫组化法结果显示C3a的沉积情况与酶联免疫吸附试验结果一致。蛋白免疫印迹法与免�[Background]Silica nanoparticles(SiNPs)enter the human body through respiratory tract,digestive tract,and skin,causing body damage.Lung is one of the main damaged organs.[Objective]To observe the expressions of complement activated fragment C3a and its receptor C3aR in the lungs of mice exposed to SiNPs through respiratory tract,and to explore the involvement of C3a/C3aR in lung injury induced by SiNPs exposure.[Methods]The ultrastructure of SiNPs(particle size 5-20 nm)was determined under a transmission electron microscope,and the hydrodynamic diameter and surface Zeta potential of SiNPs were determined using a nanoparticle size analyzer.A total of 88 SPF C57BL/6J mice were randomly divided into five groups:a blank control group without any treatment(14 mice),a vehicle control group treated with 50μL stroke-physiological saline solution by intratracheal instillation(14 mice),and three SiNPs exposure groups(low-dose group,medium-dose group,and high-dose group with 20 mice in each group,who were given 50μL SiNPs suspension of 7,21,and 35 mg·kg^(−1)respectively and exposed once every 3 days for 5 times).The mice were anesthetized on day 1(1-day model group)and day 15(15-day model group)after exposure,then sacrificed after extraction of bronchoalveolar lavage fluid(BALF),and lung tissues were retained.The morphological changes of lung tissues were observed by HE staining,the expression level of C3a in BALF was detected by enzyme-linked immunosorbent assay,the deposition of C3a and C3aR in lung tissues were observed by immunohistochemistry,the protein expression level of C3aR was determined by Western blotting,and the localization and semi-quantitative detection of C3a and C3aR in lung tissues was observed by immunofluorescence.[Results]SiNPs agglomerated in stroke-physiological saline solution.The average hydrodynamic diameter was(185.60±7.39)nm and the absolute value of Zeta potential was(43.33±0.76)mV.The condition of mice in the 1-day model group and the 15-day model group was good,while 2 mice died in the

关 键 词：纳米二氧化硅 气管滴注 肺损伤 C3A C3aR 

分 类 号：R114[医药卫生—卫生毒理学]