基于TLR4信号通路研究利拉鲁肽对脂多糖诱导的原代小胶质细胞炎症反应的作用机制  

Mechanism of action of liraglutide on lipopolysaccharide-induced inflammatory response in primary microglia based on TLR4 signaling pathway

作　　者：杨泽麟 荣曦[1] 刘红[1] Yang Zelin;Rong Xi;Liu Hong(Department of Geriatric Endocrinology and Metabolism,The First Affiliated Hospital of Guangxi Medical University,Nanning 530021,China)

机构地区：[1]广西医科大学第一附属医院老年病学内分泌代谢科,南宁530021

出　　处：《广西医科大学学报》2022年第4期547-551,共5页Journal of Guangxi Medical University

基　　金：国家自然科学基金资助项目(No.81760154);广西自然科学基金资助项目(No.2017JJA10168)。

摘　　要：目的:基于Toll样受体4(TLR4)信号通路,探索利拉鲁肽抑制脂多糖(LPS)诱导的原代小胶质细胞炎症反应的机制。方法:选取出生1 d SPF级SD大鼠,分离培养原代小胶质细胞,利用免疫荧光染色特异性蛋白Iba-1检测其纯度,将细胞随机分为5组:空白对照(N)组、脂多糖(LPS)组、利拉鲁肽(Li)组、脂多糖+利拉鲁肽(LL)组及脂多糖+TLR4抑制剂(LT)组。LPS组用LPS干预24 h,Li组用利拉鲁肽干预24 h,LL组用LPS干预24 h+利拉鲁肽干预24 h,LT组用LPS干预24 h+TAK-242干预24 h。用流式细胞仪测定各组细胞总凋亡率,以蛋白质免疫印迹法(Western blotting)检测IL-1β、TNF-α、TLR4、MyD88、TRAF6蛋白在各组中的表达情况。结果:与N组比较,LPS组细胞总凋亡率上升(P<0.05);与LPS组比较,LL组和LT组细胞的总凋亡率呈下降趋势(P<0.05)。与N组比较,LPS组IL-1β、TNF-α、TLR4、MyD88、TRAF6蛋白相对表达量增高(P<0.05);与LPS组比较,LL组和LT组IL-1β、TNF-α、TLR4、MyD88、TRAF6蛋白表达呈下降趋势(P<0.05)。结论:利拉鲁肽可能通过下调TLR4信号通路中关键因子表达抑制LPS诱导的原代小胶质细胞炎症反应,并改善细胞凋亡,保护神经系统。Objective:To explore the mechanism of liraglutide(Li)inhibiting lipopolysaccharide(LPS)-induced inflammatory response in primary microglia based on Toll-like receptor 4(TLR4)signaling pathway.Methods:Primary microglia were isolated and cultured from 1-d-old SPF SD rats,and the purity of cells was detected using immunofluorescence staining for the specific protein Iba-1.The cells were randomly divided into five groups:normal control(N)group,LPS group,Li group,LPS+Li(LL)group and LPS+TLR4 inhibitor(LT)group.LPS group was treated with LPS for 24 h,Li group was treated with liraglutide for 24 h,LL group was treated with LPS and liraglutide for 24 h respectively,and LT group was treated with LPS and TAK-242 for 24 h respectively.The total apoptosis rate of each group was measured by flow cytometry,and the protein expressions of IL-1β,TNF-α,MyD88,TLR4 and TLR4 were detected by western blotting.Results:The total apoptotic rate of cells in the LPS group was increased compared with the N group(P<0.05).The total apoptotic rate of cells in the LL anded with LPS and liraglutied for 24 h respectively,and LT group was treated with LPS and TAK-242 for 24 h respectively.LT reatgroups showed a decreasing trend compared with the LPS group(P<0.05).The relative expressions of IL-1β,TNF-α,TLR4,MyD88,and TRAF6 proteins were increased in the LPS group compared with the N group(P<0.05).The expressions of IL-1β,TNF-α,TLR4,MyD88,and TRAF6 proteins in the LL and LT groups showed a decreasing trend compared with the LPS group(P<0.05).Conclusion:Li may inhibit LPS-induced inflammatory response in primary microglia by down-regulating the expressions of key factors in TLR4 signaling pathway,ameliorating apoptosis and protecting the nervous system.

关 键 词：利拉鲁肽 TLR4 脂多糖 小胶质细胞 

分 类 号：R965[医药卫生—药理学]