金钗石斛生物总碱对β淀粉样蛋白25-35片段所致PC12细胞损伤的保护作用

Protective effects of Dendrobium nobile Lindl. alkaloids on amyloid beta 25-35-injury in PC12 cells

目的研究金钗石斛生物总碱(Dendrobium nobile Lindl.alkaloids,DNLA)对β淀粉样蛋白25-35(amyloid beta 25-35,Aβ25-35)诱导的PC12细胞损伤的影响。方法经老化处理的Aβ25-35(20μmol/L)建立PC12细胞损伤模型(即模型组),溶媒对照组给予溶剂二甲基亚砜(1‰DMSO)培养,不同浓度DNLA(0.25或2.5 mg/L)预处理细胞后,MTT法分别检测8、12、24和48 h细胞的存活率,光镜下观察细胞形态的变化,Hoechst 33258荧光染色检测细胞凋亡。结果与溶媒对照组相比,单用Aβ25-35处理(模型组)细胞存活率显著降低(P<0.05),部分细胞皱缩、变圆、脱落,Hoechst 33258染色显示细胞核固缩、碎裂,出现凋亡;而DNLA 0.25 mg/L预处理24、48 h或2.5 mg/L预处理12、24、48 h后,细胞存活率高于模型组(P<0.05),细胞连接较紧密,外形较规则,Hoechst 33258荧光染色显示细胞核呈圆形、透亮,凋亡明显减轻。结论 DNLA对Aβ25-35所致PC12细胞损伤具有保护作用。

Objective To investigate the effect of DNLA on amyloid beta 25- 35 – induced toxicity in PC12 cells. Methods Cells were treated with DNLA at different concentrations（ 0. 25 or 2. 5 mg / L） followed by exposed to Aβ25- 35（ 20 μmol/L） intoxication. Vehicle control group was treated by 1‰DMSO. Cell activity was determined by MTT assay in PC12 pre- treated with DNLA（ 0. 25 or 2. 5 mg / L） for 8,12,24,48 h. Cell damage was detected through a light microscope. Apoptosis of cells were determined by immunofluorescence method. Results After exposed to Aβ25- 35,the survival rate of cell decreased（ P 〈0. 05）,accopamined by in part of cells shrinkage,rounded off,the nucleus condensates and fragments compared with the vehicle control group. The cell survival rate increased when cells were pre- treated with 0. 25 mg / L DNLA for 24,48 h or 2. 5mg / L DNLA for 12,24,48 h（ P 0. 05）. Moreovercell body shape was regular and the cells connected more closely. Finally,the nucleus was dyed bright blue. Conclusion DNLA possesses protective effects on the injury of PC12 cells induced by Aβ25- 35.