Aβ诱导PC-12细胞凋亡建立阿尔茨海默病细胞模型

目的:用β-淀粉样蛋白(Aβ_(25-35))诱导PC-12细胞凋亡以建立阿尔茨海默病细胞模型。方法:体外培养大鼠嗜铬细胞瘤PC-12细胞,以不同浓度Aβ_(25-35)诱导并于不同时间收获细胞,应用MTT法观察细胞活力,Fura-2/AM荧光分析法检测细胞内游离Ca~(2+)浓度,Hoech-st33258及碘化丙啶复染分析细胞凋亡。结果:Aβ_(25-35)作用于PC-12细胞后,细胞活力逐渐下降,并呈时间和剂量依赖性;同时细胞内Ca~(2+)浓度显著上升;不同浓度Aβ_(25-35)作用后,PC-12细胞于不同时间出现凋亡的典型形态学特征,该时间比Ca~(2+)浓度上升约晚6-12 h。结论:Aβ_(25-35)诱导PC-12细胞活力下降、细胞内Ca~(2+)浓度上升及细胞凋亡,可作为较理想的阿尔茨海默病细胞模型。

Set up Alzheimer's Disease Cell Apoptosis Model with PC-12 Cell Induced by Aβ25-35

Objective: To prepare an apoptosis cell model of Alzheimer Disease (AD) by PC-12 cells treated with β-amyloid protein (Aβ). Methods: PC-12 cells were incubated with different concentrations of Aβ25-35 for different duration in vitro. The cell viability was detected by MTT assay. Morphological features of apoptosis were analyzed with Hoechst 33258/Propidium iodide dual staining, The level of intracellular free calcium (Ca2+]i) was cakculated by Fura-2/AM fluorescence and concentration-dependent manner, and the maximal apoptosis happened at 48 h after exposure to 20 μmol/L of Aβ25-35 and 36 h to 30 μmol/L. Cell death reached the peak at 12-24 h later than the apopconcentration of Aβ25-35. The time of the highest increase rate of Ca2+]i was about 12 h earlier than that of apoptosis. Conclusion: An AD cell model using the PC-12 cells induced with Aβ25-35 displays a series of changes related to apoptosis, which may be related to elevation of Ca2+]i.