肠道菌群通过NLRP3介导神经炎症调节rmTBI导致的记忆功能障碍  

The intestinal flora regulating memory dysfunction caused by rmTBI through NLRP3 mediating neuroinflammation

作　　者：汪家文 李佳洁 吴君 吴文鑫 杨林 WANG Jiawen;LI Jiajie;WU Jun;WU Wenxin;YANG Lin(School of Forensic Medicine/Forensic Judicial Appraisal Center,Guizhou Medical University,Guiyang,Guizhou 550004,China;School of Biology and Engineering/School of Health Medicine Modern Industry,Guizhou Medical University,Guiyang,Guizhou 550004,China)

机构地区：[1]贵州医科大学法医学院/法医司法鉴定中心,贵阳550004 [2]贵州医科大学生物与工程学院/健康医药现代产业学院,贵阳550004

出　　处：《重庆医学》2023年第20期3048-3054,共7页Chongqing medicine

基　　金：贵州省科技厅基金项目(黔科合平台人才[2018]5779-3);国家级大学生创新创业训练计划项目(202110660004)。

摘　　要：目的探讨肠道菌群通过海马核苷酸结合寡聚化结构域样受体3(NLRP3)介导神经炎症调节重复轻度创伤性脑损伤(rmTBI)导致的记忆功能障碍的机制。方法建立rmTBI大鼠模型,将大鼠分为对照组(con)组,rmTBI组,rmTBI+生理盐水灌胃(rmTBI+saline)组,rmTBI+粪便溶液灌胃粪菌移植(rmTBI+FMT)组4组。Morris水迷宫实验(MWM)检测不同组别大鼠神经记忆功能,干湿法检测大鼠脑水肿程度,16SrRNA检测大鼠肠道菌群种类及丰度,ELISA法及免疫组织化学法(IHC)检测NLRP3、caspase-1、白细胞介素(IL)-18、IL-1β表达情况。结果在MWM中,rmTBI大鼠潜伏期明显增加(P<0.001)、穿越平台次数明显减少(P<0.01),经FMT治疗后,潜伏期明显减少(P<0.05),穿越平台次数明显增加(P<0.01)。脑含水量和苏木素-伊红(HE)染色结果显示,rmTBI后大鼠脑水肿明显。IHC结果显示:rmTBI后胶质纤维酸性蛋白(GFAP)、离子钙接头蛋白1(Iba-1)表达水平明显升高(P<0.05),FMT后降低(P<0.05)。与rmTBI组及rmTBI+saline组相比,FMT后,大鼠血清NLRP3、caspase-1、IL-18表达水平均明显降低(P<0.05);与rmTBI组相比,FMT干预后大鼠血清IL-1β表达水平明显降低(P<0.001)。从结构分析来看16S rRNA检测结果,FMT后,在门水平上,拟杆菌门、变形菌门丰度均减少;在属水平上,乳杆菌属丰度增加。肠道菌群失调与神经炎症、记忆功能障碍相关性分析显示三者具有相关性。结论rmTBI后大鼠肠道菌群失调,引起大鼠空间记忆功能减弱,而FMT通过调节炎症通路能改善rmTBI大鼠记忆功能。Objective To explore the mechanism by which the gut microbiota mediates neuroinflammation and regulates memory impairment caused by repeated mild traumatic brain injury(rmTBI)through NLRP3.Methods Mild rmTBI rat models were established,and the rats were divided into four groups:the control(con)group,the rmTBI group,the rmTBI+saline group,and the rmTBI+fecal solution gavage fecal microbiota transplantation(rmTBI+FMT)group.Morris water maze experiment(MWM)was used to detect the neural memory function of different groups of rats,dry and wet weighing method was used to detect the degree of brain edema in rats,16SrRNA was used to detect the types and abundance of gut microbiota in rats,ELISA and immunohistochemistry staining(IHC)were used to detect NLRP3,caspase-1,interleukin(IL)-18,IL-1β expression.Results In MWM,the latency of rmTBI rats was significantly increased(P<0.001),and the number of crossing platforms was significantly decreased(P<0.01).After FMT treatment,the latency was significantly decreased(P<0.05),while the number of crossing platforms was significantly increased(P<0.01).The brain water content and HE staining results showed significant brain edema in rats after rmTBI.IHC results showed that the expression levels of glial fibrillary acidic protein(GFAP)and lonized calcium binding adapter molecule 1(Iba-1)were significantly increased after rmTBI(P<0.05),but were dec-reased after FMT(P<0.05).Compared with rats in the rmTBI group and rmTBI+saline group,the serum expression levels of NLRP3,casease-1,and IL-18 were significantly reduced after FMT(P<0.05).Compared with the rmTBI group,serum expression level of IL-1β in rats after FMT intervention significantly decreased(P<0.001).From a structural analysis perspective,at the phylum level,both Bacteroidetes and Proteobacteria were decreased.At the genus level,Lactobacillus genus was improved.The correlation analysis among intestinal microbiota imbalance,neuroinflammation and memory impairment showed a correlation.Conclusion After rmTBI,the intestinal microb

关 键 词：创伤性脑损伤 记忆功能障碍 肠道菌群 NLRP3 神经炎症 

分 类 号：R651.15[医药卫生—外科学]