不同价态锰对多巴胺能神经细胞凋亡作用的影响

Effects of manganese with different valences to apoptosis of SH-SY5Y cell

为探讨不同价态锰对细胞凋亡的影响 ,选用多巴胺能神经细胞 (SH SY5Y细胞 )作为锰神经毒作用的体外测试体系 ,研究二价锰 (Mn2 + )和三价锰 (Mn3+ )对SH SY5Y细胞凋亡的诱导作用以及对多巴胺 (DA)含量的影响。结果显示 :MTT法检测细胞损伤的程度 ,显示Mn2 + 和Mn3+ 呈时间和剂量依赖性的损伤SH SY5Y细胞 ;流式细胞技术证实Mn2 + 和Mn3+ (0 5～ 2mmol L)与SH SY5Y细胞接触 2 4～ 72h ,可诱导细胞发生凋亡 ,透射电镜技术发现凋亡细胞出现核染色体凝集。用高效液相色谱仪测定发现DA含量降低。说明锰所致神经细胞死亡方式是以凋亡为主 ;不同价态锰可引起细胞自身合成的DA含量下降 ,但Mn3+ 的毒作用高于Mn2 +

To study the effect of manganese with different valences to apoptosis,human neuroblastoma cell line (SH-SY5Y) has been chosen to study the induction of Mn 2+ and Mn 3+ on apoptosis and the content of dopamine in vitro. The results showed that both Mn 2+ and Mn 3+ induced a time-dependent decrease in SH-SY5Y cell viability, as determined by MMT assay. In the meantime, apoptosis was inducted by flow cytometer analysis (FCAS) after culture of Mn 2+ or Mn 3+ (0.5-2mmol/L) with SH-SY5Y cell for 24-72h. The ultrastructural changes of apoptosis such as nuclear chromosome condensation, was seen by transmission electron microscope. In addition, DA content was decreased by measured with HPLC. The major path of cell death induced by Mn 2+ and Mn 3+ may be due to apoptosis. Both Mn 2+ and Mn 3+ could induce the reduction of DA content. All these results suggest that Mn 3+ appeared to be more cytotoxic than Mn 2+.