阻断淀粉样前体蛋白-C端片段毒性通路对Cofilin磷酸化的影响

Effect of blocking toxicity pathways of C-terminal Fragment of Amyloid Precursor Protein on ADF/Cofilin in rat primary neuronal culture cells

目的本研究欲探讨阻断淀粉样前体蛋白-C端片段(Amyloid Precursor Protein C Terminal Fragments,APP-CTFs)毒性通路对Cofilin磷酸化的影响方法大鼠胚鼠大脑皮层神经元细胞培养,采取3种方法阻断APPCTFs毒性通路。1APP-695转染后γ-内切酶抑制剂DAPT处理2利用YENPTY段删除的pEGFP-APP C99,C57转染至大鼠神经元细胞3GSK-3β抑制剂LiCl处理,3种方法阻断后,均采用蛋白印迹方法检测Ph-cofilin蛋白水平。结果 DAPT处理组与未处理组比较Ph-cofilin蛋白表达水平降低(P<0.05)。转染YENPTY段删除的pEGFPAPP CTFs组未能明显增强磷酸化Cofilin的蛋白表达水平(P>0.05),虽然转染APP-CT99,57-pEGFP组与空载体对照组相比较,Ph-Cofilin蛋白表达水平明显增加(P<0.05)。LiCl处理组与非处理组相比,Ph-Cofilin蛋白表达无明显改变(P>0.05)。结论提示APP-CTFs诱导的Cofilin磷酸化过程与APP-CTFs核转移毒性通路有关,但与其诱导的GSK-3β-Tau毒性通路无关。

Objective In this study,we aim to eluciate the effects of blocking toxicity pathways of APP-CTFs on cofilin phosphorylationMethods rat primary neuronal cells were cultured and choosed three different blocking toxicity pathways of APP-CTFs.① transfected with APP-695 Full length cDNA,and treated with an inhibitor ofγ-secretase,DAPT② transfected with deletion of YENPTY domain of APP-CTFs.③ treated with an inhibitor of GSK-3β,LiCl.Results As an inhibitor ofγ-secretase,DAPT treatment decreased the phospho-cofilin（Ph-cofilin）protein levels in the transfected group with a full length of APP-695.When transfected with the deletion of the YENPTY domain of mutated APP-CTFs,Ph-cofilin did not have any significant increase.As an inhibitor of GSK-3β,LiCl treatment did not block the APP-CTFs that induced cofilin phosphorylation.Conclusion Indicating that this may be related to the translocation of the nucleus pathway;but not mediated by the GSK-3β pathway.