应用AFM研究淀粉样蛋白诱导PC12细胞损伤的机制  

The study of PC12 cell apoptosis induced by amyloid protein through AFM

作　　者：彭元[1,2] 柯长洪[1,2] 马丽娜[1,2] 陈伟[1,2] 蔡继业[1,2] 

机构地区：[1]暨南大学光电信息与传感技术广东普通高校重点实验室,广东广州510632 [2]暨南大学生命科学技术学院化学系

出　　处：《中国老年学杂志》2011年第23期4610-4612,共3页Chinese Journal of Gerontology

基　　金：国家自然科学基金资助项目(30872404);“973计划”资助项目(2010CB/833603)

摘　　要：目的利用原子力显微镜(Atomic force microscopy,AFM)对淀粉样蛋白(Aβ25～35)处理前后细胞全貌和表面超微结构进行成像分析,为进一步了解Aβ25-35诱导的细胞膜损伤机制提供可视化的依据。方法用不同浓度的Aβ25～35处理PC12细胞,CCK-8实验检测细胞活性,流式细胞术分析细胞凋亡,AFM对细胞进行表面超微结构成像和粒径分布分析。结果 CCK-8实验表明,随着Aβ25～35蛋白浓度的增加,细胞活性明显下降,特别是Aβ25～3525μmol/L时细胞活性明显低于正常组。流式细胞术分析细胞凋亡,Aβ25～35浓度在15μmol/L(低浓度诱导组)时,细胞凋亡率为(5.60±0.61)%;但在25μmol/L时(高浓度诱导组),细胞凋亡率达到(16.17±0.79)%(P<0.01),可见,随Aβ25～35浓度增加,细胞凋亡越明显;AFM分析细胞形貌和超微结构,随着Aβ25～35蛋白浓度增加,细胞塌陷更严重,细胞表面孔洞增加,颗粒物质粒径减小,细胞膜损伤程度更大。结论 AFM分析数据表明,诱导组细胞活性下降,出现细胞凋亡,细胞膜受到损伤。Objective To study the ultrastructure of PC12 cells before and after treatment with amyloid protein（Aβ25-35） by atomic force microscopy（AFM） for further understanding the amyloid protein-induced membrane damage mechanism.Methods PC12 cells were treated with different concentrations of Aβ25-35.The cell activity,cell apoptosis,membrane ultrastructure and size distribution were characterized by CCK-8 cell viability assay,flow cytometry（FCM）,and AFM.Results CCK-8 experiments showed that the significant decrease in cell viability was induced by increased concentrations of Aβ25-35,which was significantly lower than that of the normal group,especially in the concentration of 25 μmol/L.Flow cytometry analysis demonstrated that the apoptosis rate was（5.60±0.61） % when Aβ25-35 concentration was 15 μmol/L in low concentration group.However,the apoptosis rate was up to（16.17±0.79） %（P〈0.01） when Aβ25-35 concentration was increased to 25 μmol/L in high concentrations group.This indicated that more apoptosis was appeared through increased concentrations of Aβ25-35.AFM images demonstrated that the more collapse and more holes were appeared with increased concentrations of Aβ25-35.Specially,cell membrane damage and increased particle size were observed.Conclusions When cells treated with increased concentration of Aβ25-35,cells is appeared apoptosis and membrane is damaged.

关 键 词：淀粉样蛋白 PC12细胞 原子力显微镜 

分 类 号：R363.21[医药卫生—病理学] Q241[医药卫生—基础医学]