【摘要】 目的观察铁剥夺诱导K562细胞凋亡与Caspase-3激活间的关系。方法以不同水平的去铁胺(DFO)处理K562细胞。1.用磷脂结合蛋白V/碘化丙啶(Annexin V/PI)对K562细胞进行双标记后,在流式细胞仪下检测细胞凋亡率。2.采用肽核酸(pNA)标记底物的比色法检测Caspase-3活性。3.用Western blot分析Caspase-3活性蛋白的激活。结果K562细胞经不同浓度DFO处理后,细胞发生明显凋亡,Caspase-3活性渐升高。50、100μmol/L DFO作用于K562细胞24 h后,Caspase-3酶活性升高明显;与对照组比较,有显著性差异(P<0.001);在100μmol/L浓度下14 h可见活性Caspase-3,Caspase-3活性和量为时间-剂量依赖性;10、12 h各浓度组间Caspase-3活性水平比较,差异均无显著性(P均>0.05)。上述作用可被等摩尔浓度的氯化铁(FeCl3)抵消。结论铁剥夺可能通过螯合细胞内铁,激活Caspase-3,诱导K562细胞凋亡。更多还原

【Abstract】 Objective To observe the relationship between apoptosis of K562 cell induced by iron-deprivation and activation of Caspase-3.Methods K562 cells were treated with desferrioxamine（DFO） in different dosages were collected at different time points.K562 cells were labelled with Annexin V/PI,and then the rate of apoptosis was measured by flow cytometry;The activation of Caspase-3 were detected by colorimetric method with pAN labelled substrate;The active protein of Caspase-3 were analyzed by Western blot.Results When K562 cells were treated with different concentrations of DFO,the apoptosis rate and the activity of Caspase-3 increases gradually.When K562 cells were incubated with DFO（50 μmol/L and 100 μmol/L） 24 h later,the enzymatic activity of Caspase-3 increases dramatically more than that of control group,and the difference was significantly（P<0.001）;The active protein of Caspase-3 could been found when K562 cells were treated with DFO（100 μmol/L） 14 h later,the activity and the quantity of Caspase-3 depends on time-dosage;Compared with control group at 10 h and 12 h time point,the activation of Caspase-3 was not different significantly from each other（P>0.05）.All those effect above can be counteracted by equal mole concentration of FeCl₃.Conclusion Iron-deprivation maybe induce the apoptosis of K562 cell by chelating intracellular iron and activing Caspase-3.更多还原