小檗碱诱导耐药急性淋巴细胞白血病细胞株EU-4凋亡及其机制

目的 探讨小檗碱对耐药急性淋巴细胞白血病细胞株EU-4的凋亡诱导作用及其机制.方法 0、10、1 00 μmol／L小檗碱作用EU-4细胞72 h,采用流式细胞术检测细胞凋亡,免疫印迹法检测Caspase-3、PARP及X连锁凋亡抑制蛋白（XIAP）的蛋白表达,比色法检测Caspase-3的活性变化,基因沉默技术观察降低XIAP表达对于细胞凋亡的影响.结果 0、10、100μmol／L小檗碱作用EU-4细胞72 h后凋亡率分别为（9.08±1.20）％、（22.36±2.16）％、（59.81±4.17）％,呈剂量-效应关系.凋亡过程中Caspase-3的活性增强,分别为1.70±0.25、1.92±0.10、2.89±0.25.小檗碱抑制EU-4细胞XIAP的表达（P＜0.05）,并呈剂量和时间依赖关系.单纯下调XIAP蛋白的表达引起细胞凋亡,对照siRNA转染组和XIAP siRNA转染组细胞凋亡率分别为（9.23±1.66）％和（22.15±0.63）％.结论 小檗碱可以诱导急性淋巴细胞白血病EU-4细胞凋亡,XIAP下调引起的Caspase-3的激活参与了EU-4细胞的凋亡.

Molecular mechanism of berberine induced apoptosis in chemoresistant acute lymphocytic leukemia cell line EU-4

Objective To study the molecular mechanism of berberine induced apoptosis in chemoresistant EU-4 acute lymphocytic leukemia cells.Methods EU-4 cells were treated with 0,10 and 100 μmol/L berberine for 72 h.The apoptosis induced by berberine was detected by flow cytometry.The expression of Caspase-3,PARP and X-linked inhibitor of apoptosis protein （XIAP） were determined by Western bolt assay.Caspase-3 activity was measured using microplate reader.After transfected with XIAP siRNA,the apoptosis was detected by flow cytometry.Results After treated with 0,10 and 100 μmol/L berberine for 72 h,the apoptosis rates of EU-4 cells were （9.08±1.20） ％,（22.36±2.16） ％ and （59.81±4.17） ％,respectively.Berberine induced potent apoptosis in a dose-dependent manner.The apoptosis involved activation of Caspase-3.The Caspase-3 activities were 1.70±0.25,1.92±0.10 and 2.89±0.25,respectively.Berberine inhibited XIAP expression in a dose-and time-dependent manner （P ＜ 0.05）.Down-regulation of XIAP by siRNA increased apoptosis of EU-4 cells.The apoptosis rates were （9.23±1.66） ％ and （22.15±0.63） ％.Conclusion Berberine could induce apoptosis of EU-4 cells,and inhibition of XIAP leading to Caspase-3 activation is responsible for the apoptotic effect on EU-4 cells.