脂多糖预适应通过减轻血脑屏障破坏保护脑缺血再灌注大鼠  

Lipopolysaccharide preconditioning protects rats against cerebral ischemia reperfusion injury by reducing the damage of blood-brain barrier

作　　者：杨利强 徐伟杰 关欣 Yang Liqiang;Xu Weijie;Guan Xin(Kunming Health Vocational College,Kunming 650600,China)

机构地区：[1]昆明卫生职业学院,昆明650600

出　　处：《国际脑血管病杂志》2022年第11期826-831,共6页International Journal of Cerebrovascular Diseases

基　　金：云南省教育厅科学研究基金项目(2022J1879,2019J1027,2023J2207)。

摘　　要：目的探讨脂多糖(lipopolysaccharide,LPS)预适应对脑缺血再灌注大鼠的保护作用。方法120只成年雄性SD大鼠随机分为假手术组、模型组、LPS小剂量组(0.05 mg/kg)、LPS中等剂量组(0.15 mg/kg)和LPS大剂量组(0.45 mg/kg)。通过腹腔注射LPS进行预适应,1次/d,连续7 d,最后一次注射后24 h采用线栓法构建左侧大脑中动脉闭塞模型,缺血1.5 h后再灌注。在再灌注后24 h时,通过神经行为学评价神经功能缺损,通过三苯基氯化四氮唑染色测定脑梗死体积,通过酶联免疫吸附法检测血清促炎性细胞因子白细胞介素(interleukin,IL)-1、IL-6以及肿瘤坏死因子(tumor necrosis factor,TNF)-α水平,通过蛋白质印迹分析检测缺血脑组织Toll样受体4(Toll-like receptor 4,TLR4)以及基质金属蛋白酶(matrix metalloproteinase,MMP)-2和MMP-9表达。结果与假手术组比较,模型组血脑屏障通透性增加,血清IL-1β、IL-6和TNF-α上调,缺血脑组织TLR4、MMP-2和MMP-9蛋白表达上调。与模型组比较,各LPS干预组神经功能损伤显著减轻,脑梗死体积显著缩小,血脑屏障通透性显著下降,血清IL-1β、IL-6和TNF-α下调,缺血脑组织TLR4、MMP-2和MMP-9蛋白表达下调,以中等剂量组和大剂量组更为明显。结论LPS预适应能够诱导机体形成缺血耐受,抑制TLR4-MMP-2/MMP-9信号通路激活,减轻血脑屏障结构破坏和炎症,从而对脑缺血再灌注大鼠发挥神经保护作用。Objective To investigate the protective effect of lipopolysaccharide(LPS)preconditioning on cerebral ischemia reperfusion in rats.Methods One hundred and twenty adult male SD rats were randomly divided into sham operation group,model group,low-dose LPS group(0.05 mg/kg),medium-dose LPS group(0.15 mg/kg),and high-dose LPS group(0.45 mg/kg).LPS was injected intraperitoneally for preconditioning,once a day for 7 consecutive days.Twenty-four hours after the last injection,the left middle cerebral artery occlusion model was induced by suture-occluded method.The model was reperfused 1.5 h after ischemia.At 24 h after reperfusion,the neurological deficit was evaluated by neurobehavioral score.The volume of cerebral infarction was measured by triphenyltetrazolium chloride staining.The serum levels of proinflammatory cytokines interleukin(IL)-1,IL-6,and tumor necrosis factor(TNF)-αwere detected by enzyme-linked immunosorbent assay.The expression of Toll-like receptor 4(TLR4),matrix metalloproteinase(MMP)-2 and MMP-9 in ischemic brain tissue was detected by Western blot analysis.Results Compared with the sham operation group,blood-brain barrier permeability was increased in the model group,serum IL-1β,IL-6 and TNF-αwere up-regulated,and the expression of TLR4,MMP-2 and MMP-9 proteins in ischemic brain tissue was up-regulated.Compared with the model group,the neurological impairment of each LPS intervention group was significantly reduced,the volume of cerebral infarction was significantly reduced,the permeability of blood-brain barrier was significantly reduced,the serum IL-1β,IL-6 and TNF-αwere down-regulated,and the expression of TLR4,MMP-2 and MMP-9 protein in ischemic brain tissue was down-regulated,especially in the medium-dose group and the high-dose group.Conclusions LPS preconditioning can induce the formation of ischemic tolerance,inhibit the activation of TLR4-MMP-2/MMP-9 signal pathway,reduce the damage and inflammation of blood-brain barrier structure,and thus play a neuroprotective role in rats with cereb

关 键 词：脑缺血 再灌注损伤 脂多糖类 缺血预处理 血脑屏障 炎症 疾病模型 动物 大鼠 

分 类 号：R743.3[医药卫生—神经病学与精神病学]