维生素E琥珀酸酯下调mdr1/P-gp表达逆转K562/ADM耐药细胞的凋亡抑制

Vitamin E Succinate Overcomes Apoptosis Resistance in Multidrug-resistant K562/ADM Cells by Down-regulating Expression of mdr1 Gene and Its Product P-glycoprotein

摘要: 目的研究维生素E琥珀酸酯(VitaminEsuccinate,VES)诱导多药耐药K562/ADM细胞凋亡的分子机制。方法采用四氮唑蓝比色法(MTT)检测K562/ADM增殖活性;细胞形态学和AnnexinV/PI双标记法检测细胞凋亡;RT-PCR检测mdr1基因和Caspase-3基因mRNA的表达;流式细胞法(FCM)测定P-gp蛋白表达水平和Caspase-3活性。结果VES显著抑制K562/ADM细胞的增殖;经VES处理后细胞形态上出现典型的凋亡改变;AnnexinⅤ/PI双染检测凋亡细胞明显增加;mdr1mRNA表达和P-糖蛋白(P-glycoprotein,P-gp)合成明显降低,Caspase-3mRNA表达和Caspase-3活性显著增强;VES增加K562/ADM细胞对ADM的敏感性。结论VES诱导mdr1/P-gp高表达的K562/ADM耐药细胞凋亡,其主要机制为下调mdr1/P-gp表达而逆转P-gp介导的细胞凋亡抑制和耐药性。

Abstract: Objective To explore the apoptotic effect of Vitamin E succinate(VES) on multidrug-resistant leukemia K562/ADM cells and the possible molecular mechanisms. Methods Human multidrug-resistant leukemia cell line K562/ADM overexpressing mdr1 gene was used as the target cells. The cell proliferating activity was assessed with a MTT colorimetric assay. The apoptosis of K562/ADM cells was investigated by optical and electronic microscopic morphology and Annexin V/PI staining. The expression of mdr1 and Caspase-3 m...