PI3K通路在抗NMDAR脑炎小鼠紧密连接和大脑功能障碍中的作用研究  

Effect of PI3K pathway on tight junction and brain dysfunction in anti-NMDAR encephalitis mice

作　　者：龚卓伟 劳大媛 李泰燕 黄文[1] Gong Zhuowei;Lao Dayuan;Li Taiyan;Huang Wen(Department of Neurology,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神经内科,南宁530021

出　　处：《广西医科大学学报》2023年第5期749-755,共7页Journal of Guangxi Medical University

基　　金：国家自然科学基金资助项目(No.82060236);广西自然科学基金资助项目(No.2019GXNSFDA245032)。

摘　　要：目的:通过检测磷脂酰肌醇3激酶(PI3K)对抗N-甲基-D-天冬氨酸受体(NMDAR)脑炎小鼠紧密连接蛋白Occludin、Claudin-5和神经元核心抗原(NeuN)表达的影响,探讨抗NMDAR脑炎小鼠脑损伤的分子机制。方法:采用多肽主动免疫法建立抗NMDAR脑炎小鼠模型。将小鼠随机分成对照组、模型组、模型+8 mg/kg LY294002组和模型+16 mg/kg LY294002组。各组均进行神经功能缺损评分,采用荧光素钠法测定各组血脑屏障(BBB)通透性;应用蛋白免疫印迹法(western blotting)检测蛋白Occludin、Claudin-5和NeuN的表达;采用实时荧光定量PCR(RT-qPCR)法检测Occludin、Claudin-5 mRNA水平;同时通过免疫组织化学法分析NeuN在脑组织中的表达情况。结果:与对照组比较,模型组小鼠短期和长期神经功能评分下降,Occludin、Claudin-5、NeuN表达水平显著降低(P<0.05),BBB通透性增加;PI3K抑制剂LY294002改善了抗NMDAR脑炎小鼠的神经功能,并减少了Occludin、Claudin-5和NeuN表达水平的降低(均P<0.05)。结论:BBB的破坏可能是抗NMDAR脑炎小鼠脑损伤的潜在机制之一;抑制PI3K可能通过上调Occludin、Claudin-5和NeuN的表达,保护BBB的完整性,从而改善抗NMDAR脑炎小鼠的神经行为。Objective:To explore the molecular mechanism of brain injury in anti-N-methyl-D-aspartate receptor(NMDAR)encephalitis mice by detecting the effect of phosphoinositide 3 kinase(PI3K)on the expressions of tight junction(TJ)proteins Occludin,Claudin-5 and neuron-specific nuclear(NeuN)in anti-NMDAR encephalitis mice.Methods:A mouse model of anti-NMDAR encephalitis was established by peptide active immunization method.The mice were randomly divided into control,model,model+8 mg/kg LY294002,and model+16 mg/kg LY294002 groups.Neurobehavioral deficit scores were performed in each group.The blood-brain barrier(BBB)permeability was measured by fluorescein sodium assay.Western blotting was used to detect the expressions of Occludin,Claudin-5,and NeuN.Real-time fluorescence quantitative polymerase chain reaction(RT-qPCR)was used to test the mRNA levels of Occludin and Claudin-5.The expression of NeuN in the brain was analyzed by immunohistochemistry.Results:Compared with the control group,the short-term and long-term neurological function scores of the model group mice decreased,the expression levels of Occludin,Claudin-5,and NeuN significantly decreased(P<0.05),while the permeability of BBB increased.PI3K inhibitor LY294002 improved the nerve function of mice with anti-NMDAR encephalitis and suppressed the decrease of Occludin,Claudin-5,and NeuN expression levels(All P<0.05).Conclusion:The destruction of BBB may be one of the underlying mechanisms of brain injury in anti-NMDAR encephalitis mice.PI3K inhibition may protect BBB integrity by up-regulating the expressions of Occludin,Claudin-5,and NeuN,thereby improving neural behavior in mice with anti-NMDAR encephalitis.

关 键 词：抗N-甲基-D-天冬氨酸受体脑炎 血脑屏障 紧密连接蛋白 神经行为改变 

分 类 号：R741[医药卫生—神经病学与精神病学]