醋酸锰对PC12细胞损伤作用的研究

Study on the mechanism of injury in manganese acetate induced PC12 cells

目的研究醋酸锰对PC12细胞的损伤作用机制。方法不同浓度醋酸锰处理PC12细胞24h后,MTT法检测细胞存活率,Hoechst 33258和DNA凝胶电泳的方法检测细胞凋亡,利用高效液相色谱—电化学方法(HPLC-ECD)检测细胞内儿茶酚异喹啉物质的生成,同时测定细胞内丙二醛(MDA)和羟自由基的生成量。结果不同水平的醋酸锰处理使PC12细胞存活率下降且呈浓度依赖性(P<0.05)。Hoechst 33258和DNA凝胶电泳结果表明细胞发生了凋亡。MDA和羟自由基的含量与对照相比明显升高(P<0.05),多巴胺(DA)的含量呈下降趋势(P<0.05)。Sal(6,7-二羟基-1,2,3,4-四氢异喹啉,Sal)和NMSal(N-甲基-6,7-二羟基-1,2,3,4-四氢异喹啉,NMSal)的含量则随锰浓度的增加而增加(P<0.05)。结论过量的醋酸锰导致PC12细胞产生高氧化应激水平,从而生成了一系列儿茶酚异喹啉物质,对细胞产生损伤作用,这可能是三价锰发挥损伤作用的途径之一。

Aim The cell injury mechanism of manganese acetate was investigated using PC12. Methods Cultured PC12 cells were exposed to Mn （Ac） 3 for 24 hours. The survival rate of PC12 cells was determined by MTT assay. Hoechst 33258 and DNA ladder were performed to monitor the apoptotic cells. HPLC-ECD was used to measure the levels of hydroxyl radical and catechol isoquinoline in cells. Lipid peroxidant product MDA was also measured. Results The viability of PC12 ceils decreased as the Mn （Ac）3 concentration increased. The manganese treatment could induce PC12 cell apoptosis. The level of MDA and hydroxyl radical increased compared with that of the control （P 〈 0. 05 ）. DA levels decreased significantly in manganese acetate treated PC12 cells （P 〈01 05）. Sal and NMSal levels increased with the increment Of manganese con- centration. Conclusion Excessive manganese can induce the high level of oxidative stress in PC12 cells, and the generation of catechol isoquinolines may be toxic to PC12 cells,which may be a way in the manganese acetate induced injury of PC12 cells.