黄芪总苷诱导人白血病NB4细胞凋亡的机制

Mechanism of apoptosis in human leukemia NB4 cells induced by total astragalosides

目的 研究黄芪总苷（TA）对体外培养的人早幼粒细胞白血病细胞株NB4增殖及凋亡机制的影响.方法 将不同浓度的TA与NB4细胞共培养48 h,采用细胞增殖及细胞毒性检测试剂盒8（CCK-8）检测细胞生长抑制率,以流式细胞仪检测细胞凋亡率及凋亡过程中细胞内核因子κB（NF-κB）和蛋白激酶B（PKB,又称Akt）蛋白浓度的变化.结果 200、400、600、800 ms/L TA均可抑制NB4细胞生长,抑制率分别为（14.54±3.20）%、（24.79±3.98）%、（57.28±4.71）%和（88.28±4.65）%,呈浓度依赖性增加（P〈0.05）.200、400、600、800 mg/L TA组的细胞凋亡率分别为（10.03±3.31）%、（14.87±3.65）%、（23.45±1.90）%和（25.26 4-2.07）%,与对照组[（1.80±1.24）%]相比,差异均有统计学意义（P〈0.05）,且200、400、600 ms/L TA组的细胞凋亡率呈浓度依赖性增加（P〈0.05）;800 mg/L TA组的细胞凋亡率增加不明显,与600 ms/L TA组相比,差异无统计学意义（P〉0.05）,但出现了大量的坏死细胞,坏死率达（45.65±3.16）%.细胞凋亡过程中伴随NF-κB蛋白表达下降,不同浓度TA组与对照组差异均有统计学意义（P〈0.05）,而Akt蛋白的表达无明显变化（P〉0.05）.结论 黄芪总苷可以抑制NB4细胞增殖,并可以通过不依赖Akt的NF-κB信号通路来诱导NB4细胞凋亡.

Objective To investigate the effect of total astragalosides （TA） on proliferation and apoptosis in human leukemia NB4 cells in vitro. Methods The NB4 cells were treated with TA at different concentrations for 48 h in culture. Growth inhibition rates were measured by CCK-8 method. Flow cytometry was used to explore the cell apoptosis and the activity of NF-κB and Akt during apoptosis. Results TA at different concentrations （200, 400, 600, 800 mg/L） inhibited proliferation of NB4 cells in a dose-dependent manner （ P 〈 0. 05）, and the inhibitory rates of TA on NB4 cells were （14. 54 ± 3. 20） % , （24.79 ±3.98）%, （57.28 ±4.71）% and （88.28 ±4.65）% , respectively. In terms of the induction of apoptosis, there was a significant difference between the TA group and blank control [（1.80±1.24）%, P〈0.05]. At TA doses of 200, 400 and 600 mg/L, the apoptotic rates of NB4 cells were （ 10. 03 ± 3.31）% , （14.87 ±3.65）% , （23.45 ± 1.90） % , respectively. Besides, TA induced apoptosis of NB4 cells in a dose-dependent manner in the groups of 200 mg/L, 400 mg/L, 600 mg/L （P〈0.05）. But there was no significant difference in apoptotic rates between the groups of 800 mg/L and 600 mg/L [（23.45 ±1.90）%, P〉 0.05]. In the group of 800 mg/L, the necrotic cells increased highly and the necrotic rate reached （45.65 ± 3.16）%. After TA treatment of NB4 cells at different concentrations （200, 400, 600 mg/L）, the expression of NF-kB protein was significantly decreased compared with that of the blank control （9. 79 ±0. 95, P〈0.05）, while Akt protein was not significantly decreased （P〉0.05）. Conclusion TA can inhibit the growth of NB4 cells and induce apoptosis in NB4 cells through an Akt-independent NF-kB signaling pathway.