牛蒡子苷元诱导人白血病细胞凋亡的作用及机制

牛蒡子来源于菊科两年生草本植物牛蒡子属牛蒡(Aictium lappa L.)的干燥成熟果实,为常用中药.有疏风散热、解毒透疹、利咽消肿等功效,现代药理学研究表明牛蒡子有抗病毒[1,5]、抗炎[2]、抗癌[3,4]、抑制热休克反应[6]等广泛的药理活性.其主要活性成分是牛蒡子苷元(arctigenin,ARG)[1].

Induction of apoptosis of the human leukemia cells by arctigenin and its mechanism of action

This study investigated the effect of arctigenin (ARG) on the induction of apoptosis and the putative pathways of its action in HL-60 and K562 cells. MTT assay was used to detect the cytotoxic effect of ARG in HL-60 and K562 cells. The apoptosis was observed by Hoechst 33258 fluorescence staining and DNA agarose gel electrophoresis. Caspase-3 enzyme activity was measured by caspase-3 enzyme activity detection kit. The expression of related protein was analyzed by Western blotting and the vascular endothelial growth factor (VEGF) level was determined by enzyme-linked immunosorbent assay (ELISA). ARG-treated HL-60 cells and K562 cells exhibited growth inhibition and displayed several features of apoptosis, including DNA fragmentation and DNA laddering by agarose gel electrophoresis. It was observed that poly-(ADP-ribose) polymeras (PARP) were cleaved to smaller molecules and ARG induced upregulation of bax and downregulation of bcl-2 protein expression. However, it had no effect on VEGF levels. Taken together, this study demonstrated that ARG is a potent inducer of apoptosis and this was accompanied by caspase-3 activation and upregulation of bax/bcl-2, which offers a potential mechanism for the apoptosis-inducing activity of ARG.