蓝萼甲素诱导K562细胞毒作用机制的初步研究

Preliminary Investigation on Glaucocalyxin A-induced Cytotoxicity in K562 Cells

目的:探讨活性氧(reactive oxygen species,ROS)在蓝萼甲素(glaucocalyxin A,GLA)诱导的人慢性粒细胞白血病K562细胞毒性中的作用。方法:GLA(0.313,0.625,1.250,2.500,5.000,10.000 mg.L-1)处理K562细胞12,24,48 h后,噻唑蓝(MTT)法观察细胞毒作用;流式细胞术检测GLA(2.5,5.0,10.0 mg.L-1)对K562细胞周期的阻滞作用;流式细胞术检测5.0 mg.L-1 GLA作用后K562中的ROS变化;利用MTT法检测抗氧化剂氮乙酰半胱氨酸(N-acetylcysteine,NAC)对GLA诱导下K562细胞毒作用的影响;流式细胞术检测NAC对GLA诱导下K562细胞周期的影响。结果:GLA对K562细胞的生长抑制呈明显的剂量和时间依赖关系,12,24,48 h的IC50分别为6.168,2.968,1.086 mg.L-1;GLA对K562细胞周期的阻滞作用主要发生在G0/G1期;5.0 mg.L-1 GLA作用K562细胞2 h后ROS较空白组上升1.3倍;NAC对GLA细胞毒作用有明显的抑制作用,且随NAC浓度上升,抑制作用增强;NAC能减弱GLA对K562的细胞周期阻滞作用。结论:GLA对K562细胞具有细胞毒及细胞周期阻滞作用,且这些作用与ROS有关。

Objective：To investigate the involvement of reactive oxygen species（ROS）in glaucocalyxin A（GLA）-induced cytotoxicity of human chronic myelogenous leukemia K562 cells.Method： After 12,24 and 48 hours treatment by GLA,3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide（MTT）assay was performed to assess the cytotoxicity.The cell cycle was studied by flow cytometry.The ROS burst induced by GLA was also determined by flow cytometry.Result： Exposure of K562 cells to GLA lead to a dose-and time-dependent cytotoxicity with IC50 values of 6.168,2.968,1.086 mg·L-1 for 12,24,48 h,respectively.The block function of K562 cells cycle after treated GLA mainly occurred on G0/G1 phase.There is a generation of ROS in K562 cell after using GLA.NAC can increase the cell viability and decrease cell cycle arrest.Conclusion：The results suggested that ROS might be involved in the K562 cytotoxicity induced by GLA.