Tau蛋白与实验性自身免疫性脑脊髓炎小鼠神经轴索损伤的相关性研究

摘要

Objective:To observe dynamic change of phosphorylated tau protein and non phosphorylated tau protein in axon and explore whether GSK3 in serum were related with phosphorylated tau protein in brain of EAE mice.Methods: Mice were randomly divided into six groups:EAE group of acute stage,EAE group of paralytic stage,EAE group of remission stage,control group of acute stage,control group of paralytic stage,control group of remission stage,each group had twelve mice.EAE model were constructed by MOG35-55 peptides in EAE group, the saline was used in control group.The nerve function scores and incidence were observed and compared.We observed degree of brain inflammation by HE staining and measured axons which contained two kinds of tau protein by immunohistochemistry.GSK3 in serum was tested to find correlation with phosphorylated tau protein in brain by ELISA method.Results:Nerve function scores in EAE group were higher than control group.The degree of inflammation damage was more serious in EAE group than control group,gradually enhancing with time.Phosphorylated tau protein in brain gradually increased before mice paralyzing(P<0.01),but it decreased when symptom relieved(P<0.01).GSK3 in serum were correlated with phosphorylated tau protein in brain(r=0.9326,P<0.01),linear regression equation:Y=2.950+0.418X.Conclusion:Phosphorylated tau protein in brain are correlated with axon damage and GSK3 in serum could indirectly reflect axon damage in brain.%目的：研究非磷酸化和磷酸化两种不同形式tau蛋白在实验性自身免疫性脑脊髓炎（ EAE）小鼠脑组织轴索中不同时期的动态变化及脑组织中磷酸化tau蛋白与血清GSK3相关性。方法：将小鼠随机分为6组，分别为EAE急性期组、EAE瘫痪期组、EAE缓解期组、对照急性期组、对照瘫痪期组、对照缓解期组，每组12只。 EAE组用MOG35-55肽段免疫建造模型，对照组生理盐水处理。比较不同时期小鼠神经功能评分；采用HE染色法对比不同时期小鼠脑组织炎症程度；免疫组化法测算脑组织不同时期tau蛋白轴索表达数；ELISA法测算小鼠不同时期血清GSK3含量，并计算其与脑组织中磷酸化tau蛋白相关性。结果：小鼠神经功能评分EAE组高于对照组。 HE染色EAE组小鼠炎症反应明显高于对照组，随时间推移炎症反应渐强。免疫组化法EAE组磷酸化tau蛋白表达高于对照组（ P＜0.01），在瘫痪期前随时间推移表达增加（ P＜0.01），缓解期表达下降（P＜0.01）。血清GSK3含量变化与脑组织磷酸化tau蛋白表达变化间存在正相关性（r＝0.9326，P＜0.01），直线回归方程：Y＝2.950＋0.418X。结论：轴索损伤与磷酸化tau蛋白具有相关性，血清GSK3可间接反应脑组织中轴索损伤程度。