中文摘要：

目的 研究阿尔茨海默病细胞模型20E2自噬情况及其可能机制。方法 应用ELISA检测体外培养的HEK293细胞和20E2细胞（稳定转染APPSW的HEK293细胞）上清Aβ1-40水平、Western blotting检测APP蛋白表达水平,确定20E2细胞是否建模成功。电镜下观察细胞内线粒体,JC-1检测两种细胞线粒体膜电位,流式细胞仪检测细胞凋亡情况。Western blotting检测LC3-II、PINK1、Parkin表达水平。结果 与HEK293细胞相比,20E2细胞APP蛋白、Aβ1-40表达增加（P〈0.05）,线粒体肿胀、嵴消失、空泡化明显,线粒体膜电位下降,PINK1、Parkin、自噬相关蛋白LC3-II表达增加（P〈0.05）。结论 阿尔茨海默病细胞模型20E2线粒体形态改变明显、膜电位下降,这些改变可能通过PINK1、Parkin途径引起线粒体自噬增加。

英文摘要：

Objective To investigate the effect of autophagy involved in Alzheimer＇s disease cell model 20E2 and its possible mechanism. Methods To determine whether the 20E2 cells model was successfully established,we detected the levels of Aβ1-40 in HEK293 cells and 20E2 cells（ HEK293 cells stably expressing Swedish mutant APP） cultured in vitro by ELISA kit,and the expression of APP protein level was detected by Western blotting. The mitochondria in cells was observed by electron microscope. The mitochondrial membrane potential of both cells was detected by fluorescence probe JC-1. Flowcytometry was used to measure the apoptotic rate. LC3-II,PINK1 and Parkin were detected by Western blotting. Results The expression levels of APP protein and Aβ1-40 increased in 20E2 cells compared with those in HEK293 cells. Mitochondrial swollen,cristae disappeared and vacuolization was obviously observed. Mitochondrial membrane potential decreased. The expression levels of PINK1,Parkin and LC3-II increased（ P〈0. 05）. Conclusion In Alzheimer＇s disease cell model 20E2,the mitochondrial morphology changed obviously and membrane potential of mitochondria declined,and these changes may cause the increase of mitochondrial autophagy through PINK1 and Parkin pathway.