BCL-2、Caspase-3、NF-KB在黄芪总苷诱导人白血病NB4细胞凋亡过程中作用

本研究探讨黄芪总苷（astragaloside，AST）对急性早幼粒细胞白血病（APL）NB4细胞株的凋亡诱导作用及其分子机制。采用AST处理人APL细胞株NB4，CCK-8比色法检测细胞增殖抑制率，FITC—Annexinv／PI双染流式细胞术检测细胞凋亡率；不同浓度AST作用NB4细胞后RT-PCR检测BCL-2mRNA表达，Westernblot检测NF-KB、BCL-2、caspase-3蛋白表达水平。结果表明，AST作用NB4细胞48h后，浓度依赖性地抑制NB4细胞的增殖，且随着AST的浓度增加，细胞凋亡率也由4．69％上升到40．85％。RT—PCR结果显示，BCL-2mRNA表达减弱；Westernblot结果显示，NF—KB及BCL-2蛋白表达减弱，caspase-3表达增强。结论：降低NF-KB、BCL-2表达并最终激活caspase-3的表达可能是AsT诱导NB4细胞株凋亡的机制之一。

Role of BCL-2, Caspase-3 and NF-KB in Astragaloside Inducing Apoptosis of Human NB4 Cells

This study was purposed to investigate the apoptosis-inducing effect of astragalosides on acute promyelocytic leukemia（APL） cell line NB4 and its mechanism. NB4 cells were treated with different concentrations （200, 300,400 μg/ml） of astragalosides for 48 h. The cell proliferation was assayed by using CCK-8 method; the cell apoptosis was analyzed by flow cytometry with Annexin V-FITE/PI double staining. The mRNA expression of BCL-2 and the relative activity of BCL-2 NF-KB and caspase-3 were detected by RT-PCR and Western blot, respectively. The results showed that after treated with astragalosides for 48 h, astragalosides inhibited NB4 cell proliferation in concentration-dependent way, the apoptosis rate of NB4 cells gradually elevated from 4.69% to 40. 85% with the increasing of astragalosides concentration. Simultaneously, the mRNA expression of BCL-2 was down-regulated, Western blot analysis showed that the protein expression levels of BCL-2 and NF-KB decreased after astragalosides treatment, while caspase-3 protein expression level increased. It is concluded that the molecular mechanism of the astragalosides-induced apoptosis in N/M cells may be associated with down-regulation of the expression of BCL-2 and NF-KB. finally the relative activity of casoase-3 activated.