铁对白血病细胞HL-60线粒体膜电位及凋亡的影响

Influence of Iron on Mitochondrion Membrane Potential and Apoptosis of Human Leukemia-60 Cells

目的研究铁对人白血病细胞HL-60线粒体膜电位(ΔΨm)及凋亡影响,探讨其可能机制。方法HL-60细胞分别与10、50、100μmol/L去铁胺(DFO)和10、100μmol/L三氯化铁(FeCl3)共培养,分别造成细胞内铁剥夺和富铁状态,噻唑蓝(MTT)法检测不同铁状态下细胞活力变化;相差显微镜观察凋亡细胞的形态学改变,流式细胞仪(FCM)检测细胞凋亡率及ΔΨm变化;原位杂交法检测凋亡基因Bax转录水平。结果DFO组细胞生长率呈下降趋势,而FeCl3组细胞生长率呈上升趋势;HL-60细胞经DFO处理后,细胞凋亡率增加、ΔΨm下降(P<0.01);100μmol/L DFO作用细胞244、8 h后,凋亡基因Bax的转录水平均较对照组增高(P<0.01)。FeCl3组细胞ΔΨm及Bax转录无明显变化,但凋亡率较对照组略下降。结论铁剥夺可降低ΔΨm,诱导HL-60细胞凋亡;而富铁对细胞ΔΨm无明显影响,但可增强细胞活力,使细胞凋亡率下降。

Objective To obaerve the change of mitochondrion membrane potential （△ψm） in apoptosis induced by an iron chelator （deferoxarnine, DFO）, and to explore the mechanism of this apoptosis in human leukemia-60 （HL-60） cells. Methods HL-60 cells were co-cultivated with various concentration of DFO and FeCl3 for certain time, resuhingin status of intracellular iron deprivation and rich iron. Cell vital force was determinded by the MTT method. The cells were examined by phase contrast microscopy, flow cytometry （FCM） for evidence of apoptosis, and also by FCM for △ψm. The transcription of the apoptngene of bax was detected by hybridization in situ. Results The cell growth rate assumed descent tendency. DFO could induce the apoptosis and de.scent △ψm of HL-60 cells（P〈0.05）. After cells being incubated with 100 μmol/L DFO for 24 h and 48 h, the level of bax transcription was higher than the control. Conclusion lron deprivation can induce apoptosis of HL-60 cells by decreasing their ; rich iron has little influence on their △ψm, instead enhance their vital force and reduce their rate of apoptosis.