摘要
目的探讨中性粒细胞弹性蛋白酶(NE)和髓过氧化物酶(MPO)对铅诱导的小鼠肝脏炎症的改善作用与机制。方法将无特定病原体级C57BL/6雄性小鼠随机分为对照组、铅暴露组、NE抑制剂组和MPO抑制剂组,每组3只。后3组小鼠均腹腔注射剂量为10 mg/kg体质量的乙酸铅溶液,对照组小鼠腹腔注射等体积0.9%氯化钠溶液,每周3次,连续4周。于最后7 d,2个抑制剂组小鼠分别予腹腔注射剂量为40 mg/kg体质量的NE抑制剂西维来司他钠或MPO抑制剂4-氨基苯甲酰肼,每天1次。观察小鼠体质量和肝脏组织病理学改变情况。采用荧光定量聚合酶链式反应法检测小鼠肝组织中炎症基因肿瘤坏死因子-α(Tnfa)、白细胞介素-1β(Il1b)、白细胞介素-6(Il6)、核酸结合寡聚结构域样受体热蛋白结构域相关蛋白3(Nlrp3)、凋亡相关点样蛋白(Asc)和半胱氨酸蛋白酶-1(Caspase1)的mRNA表达。采用蛋白质印迹法检测NLRP3、ASC和CASPASE-1蛋白表达水平。结果4组小鼠活动基本正常,体质量差异无统计学意义(P>0.05)。苏木精-伊红染色结果显示,铅暴露组小鼠肝细胞大小不一、细胞边界模糊,呈现早期炎症反应;经NE或MPO抑制剂干预后,2个抑制剂组小鼠肝组织早期炎症反应情况均有所改善,MPO抑制剂组小鼠改善程度优于NE抑制剂组。铅暴露组小鼠肝组织中Tnfa、Il1b、Il6、Nlrp3、Asc、Caspase1的mRNA和ASC、CASPASE-1蛋白的相对表达水平均高于对照组(P值均<0.05)。与铅暴露组比较,NE抑制剂组小鼠肝组织中Tnfa、Il1b、Il6、Nlrp3和Asc的mRNA相对表达水平均下降(P值均<0.05),MPO抑制剂组小鼠肝组织中Tnfa、Il1b、Il6、Caspase1的mRNA和ASC、CASPASE-1蛋白的相对表达水平均下降(P值均<0.05)。结论铅可能通过激活NLRP3炎症小体活化诱导小鼠肝脏炎症;NE或MPO抑制可通过减缓NLRP3炎症小体活化,进而改善铅诱导的小鼠肝脏炎症反应。
Objective To explore the beneficial effects and mechanisms of neutrophil elastase(NE)and myeloperoxidase(MPO)on lead-induced hepatic inflammation in mice.Methods The specific pathogen free male C57BL/6 mice were randomly divided into four groups:control group,lead-exposed group,NE inhibitor group,and MPO inhibitor group,with three mice in each group.The mice in lead-exposed group,NE inhibitor group,and MPO inhibitor group were intraperitoneally injected with a dose of 10 mg/kg body mass of lead acetate solution,while the mice of control group received an equal volume of 0.9%saline three times per week for four weeks.In the last seven days,mice in both inhibitor groups were intraperitoneally injected with a dose of 4O mg/kg NE inhibitor sivelestat sodium or MPO inhibitor 4-aminobenzoic acid hydrazide(4-ABAH)once per day.Mouse body weight and liver histopathological changes were observed.The mRNA expression of genes associated with inflammation,such as tumor necrosis factor-α(Tnfa),interleukin-1β(Il1b),interleukin-6(Il6),and nucleotide-binding oligomerization domain-like receptor protein 3(Nlrp3),apoptosis-associated speck-like protein(Asc)and cysteinyl aspartate specific proteinase(Caspasel)in the mouse liver tissues was detected by real-time quantitative polymerase chain reaction.The protein expression of NLRP3,ASC,and CASPASE-1 was detected using Western blotting.Results The activities of mice in all four groups were generally normal,and there was no significant difference in body weight(P>0.05).The results of hematoxylin-eosin staining showed that the cell size of hepatocytes varied in the lead-exposed mice,with indistinct cell boundaries,indicating early inflammatory responses in liver tissues.Afer intervention with NE or MPO inhibitors,the early inflammatory responses improved in the liver tissues of the mice in both inhibitor groups,with a better improvement observed in MPO inhibitor group compared with the NE inhibitor group.The mRNA expression of Tnfa,Il1b,Il6,NLrp3,Asc,and Caspasel,as well as the protei
作者
吴燕君
吴家韵
欧雨诗
刘苏慧
洪嘉颖
赵娜
农骐郢
黄永顺
WU Yanjun;WU Jiayun;OU Yushi;LIU Suhui;HONG Jiaying;ZHAO Na;NONG Qiying;HUANG Yongshun(School of Public Health,Southern Medical University,Guangzhou,Guangdong 510505,China;不详)
出处
《中国职业医学》
CAS
北大核心
2023年第3期262-267,273,共7页
China Occupational Medicine
基金
国家自然科学基金(81903269,22106022)
广东省自然科学基金(2021A1515010081,2021A1515011546,2021A1515012205,2023A1515012756,2023A1515010085)
广东省医学科学技术研究基金(A2022013,A2022038)
广东省职业病防治院重点科研项目(Z2022-11,Z2022-12)
广州市科技计划项目(202102080005)。
