摘要
背景:研究表明纹状体富集的酪氨酸磷酸酶61(striatal-enriched phosphatase,STEP_(61))在突触可塑性方面发挥重要作用。STEP位于后突触末端,影响突触增强的形成,可能的机制是使关键性信号蛋白如MAPK激酶ERK1/2去磷酸化并失活。目的:探讨STEP_(61)负性调控阿尔茨海默病细胞模型中β淀粉样蛋白介导的ERK信号通路的机制。方法:实验分3组,正常组为C57BL/6小鼠原代皮质神经元细胞;阿尔茨海默病细胞模型组是利用1μmol/L凝聚态的β淀粉样蛋白1-42加入皮质神经元细胞中1 h作为阿尔茨海默病细胞模型;β淀粉样蛋白1-42+RNAi组为在阿尔茨海默病细胞模型基础上,利用sRNAi技术制作STEP_(61)基因沉默组。应用Western Blot技术检测STEP_(61)的RNAi对ERK信号通路的影响。结果与结论:Western blot结果显示,阿尔茨海默病细胞模型组与正常组相比STEP_(61)蛋白表达增加了223%(P<0.05),使磷酸化STEP_(61)的比例减少到(75.6±4.6)%(P<0.05)。β淀粉样蛋白1-42+RNAi组STEP_(61)磷酸化的比例与阿尔茨海默病细胞模型组相比差异无显著性意义。同时阿尔茨海默病细胞模型组pE RK1/2的蛋白表达量较对照组减少(P<0.05),而β淀粉样蛋白1-42+RNAi组p ERK1/2的蛋白表达量较阿尔茨海默病细胞模型组显著增加(P<0.05)。结果说明:在阿尔茨海默细胞模型中证实了STEP_(61)调控β淀粉样蛋白介导的ERKs活性,并且很可能是通过脱磷酸化使他们失活而实现的。
BACKGROUND： Striatal-enriched phosphatase 61（STEP61） has been shown to play an important role in synaptic plasticity. STEP is located at the postsynaptic terminal, and affects the formation of synapticenhancement probably through the dephosphorylation and inactivation of key signal proteins such as MAPK kinase ERK1/2. OBJECTIVE： To explore the mechanism of STEP61 negatively regulating amyloid β-protein（Aβ）-mediated ERK signaling pathway in Alzheimer＇s disease cell model. METHODS： There were three groups. Normal group was primary cortical neuron cells of C57 BL/6 mice. In Alzheimer＇s disease cell model group, 1 μmol/L Aβ1-42（condensed state） was added into the cortical neuron cells for 1 hour culture to prepare Alzheimer＇s disease cell model. In Aβ_（1-42）＋ RNAi group, STEP61 gene silencing was performed in Alzheimer＇s disease cell model by s RNAi technique. The effect of STEP61 RNAi on ERK signaling pathway was detected by western blot assay. RESULTS AND CONCLUSION： The expression of STEP61 protein in the Alzheimer＇s disease cell model group was increased by 223% compared with the normal group, and the ratio of phosphorylated STEP61 was reduced to（75.6 ± 4.6）%（P〈0.05）. There was no significant difference in the ratio of STEP61 phosphorylation between Aβ_（1-42）＋ RNAi and Alzheimer＇s disease cell model groups. Western blot analysis showed an evident decrease of pERK1/2 levels in the Alzheimer＇s disease cell model group compared with the control group（P〈0.05）. The expression of p ERK1/2 protein in the Aβ_（1-42）＋ RNAi group was significantly higher than that in the Alzheimer＇s disease cell model group（P〈0.05）. These results suggest that STEP61 negatively regulates Aβ mediated ERK signaling pathway in the Alzheimer＇s disease cell model, possibly by dephosphorylation.
作者
张琳
杨菁
刘赞华
Zhang Lin;Yang Jing;Liu Zan-hua(First Department of Neurology,Dalian Municipal Central Hospital,Dalian 116000,Liaoning Province,China;Provincial Key Laboratory of Cardiovascular and Cerebrovascular Drug Basic Research,Jinzhou Medical University,Jinzhou 121001,Liaoning Province,China)
出处
《中国组织工程研究》
CAS
北大核心
2018年第28期4507-4512,共6页
Chinese Journal of Tissue Engineering Research
