肿节风总黄酮促进白血病K562细胞凋亡的效应及机制研究

Effect and Mechanism of Total Flavonoids from Sarcandrae Herba on the Apoptosis in Human Leukemia K562 Cells

目的:研究肿节风总黄酮促进人白血病K562细胞凋亡的效应及分子机制。方法:用系列浓度的肿节风总黄酮干预K562细胞24、48、72 h后,化学发光法检测细胞活力计算IC50,并依此将细胞分为空白对照组、肿节风总黄酮25、50、100μg/mL剂量组进行实验。AO-EB染色法及流式细胞术检测细胞凋亡情况,Western blot检测Bcl-2、Bax、Caspase-3、Cleaved Caspase-3蛋白表达情况。结果:肿节风总黄酮能够明显降低K562细胞存活率,且呈时间和剂量依赖关系,24、48、72 h的IC50分别为(64.90±5.16)μg/mL、(50.60±4.00)μg/mL、(34.90±2.46)μg/mL。与空白对照组相比,50、100μg/mL的肿节风总黄酮明显促进K562细胞凋亡。Western blot实验显示,与空白对照组相比,肿节风总黄酮100μg/mL剂量组Caspase-3蛋白表达显著下调;肿节风总黄酮50和100μg/mL剂量组Cleaved Caspase-3蛋白表达显著上调,Bcl-2的蛋白表达显著下调;Bcl-2/Bax比值明显减小,Cleaved Caspase-3/Caspase-3比值明显增大。结论:肿节风总黄酮能有效促进K562细胞凋亡,其机制可能与其下调Bcl-2、Caspase-3蛋白,上调Cleaved Caspase-3蛋白的表达有关。

Objective:To investigate the pro-apoptosis effect of total flavonoids from Sarcandrae Herba in Human Leukemia K562 Cells and its mechanism.Methods:K562 cells were treated with different concentrations of total flavonoids from Sarcandrae Herba for 24,48,and 72 hours.The IC50 value was calculated by chemiluminescence method,then K562 cells were divided into the control group and three doses of Total flavonoids from Sarcandrae Herba groups(25、50、100μg/mL).AO-EB staining and flow cytometry were applied to detect total flavonoids-induced apoptosis in K562 cells.The protein expression levels of Bcl-2,Bax,Caspase-3 and Cleaved Caspase-3 in K562 cells were detected by Western blotting.Results:Total flavonoids from Sarcandrae Herba significantly reduced the survival rate of K562 cells,in a concentration-time-dependent manner.The IC50 values were(64.90±5.16)μg/mL,(50.60±4.00)μg/mL,and(34.90±2.46)μg/mL at 24,48,and 72 h,respectively.Compared with the control group,total flavonoids significantly promoted the apoptosis in K562 cells.Compared with the control group,the expression of Caspase protein was down regulated,the expression of Caspase-3 protein was up regulated in 100μg/mL group.In 50μg/mL and 100μg/mL Total flavonoids groups,the expression of Cleaved Caspase-3 protein was significantly up regulated,while the expression of Bcl-2 was significantly down regulated.The protein expression ratio of Bcl-2/Bax was decreased,while the protein expression ratio of Cleaved Caspase-3/Caspase-3 was increased.Conclusion:Total flavonoids from Sarcandrae Herba can promote the apoptosis in K562 cells,which may be related to down-regulating the expressions of Bcl-2 and Caspase-3 protein,and up regulating the expression level of Cleaved Caspase-3 protein.