Liu Jiajun, Huang Renwei, Lin Dongjun, Wu Xiangyuan, Peng Jun, Lin Qu, Pan Xianglin, Zhang Maohong, Hou Ming, Chen Feng
Department of Hematology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China.
Leuk Lymphoma. 2005 Apr;46(4):593-7. doi: 10.1080/10428190400019800.
The anti-proliferation effects of oridonin on acute promyelocytic leukemia (APL) cells and its mechanisms were studied in vitro. NB4 cells as well as fresh leukemia cells obtained from APL patients in culture medium were treated with different concentrations of oridonin. Cell growth inhibition, apoptosis and related pathways were assessed by MTT assay as well as flow cytometry (FCM) and western blot analysis. The data revealed that oridonin (over 16 micromol/L) could inhibit the growth of NB4 cells by induction of apoptosis. Marked changes of cell apoptosis were observed very clearly by using electron microscopy and DNA fragmentation analysis after the cells exposed to oridonin for 48 h; Western blotting showed cleavage of the caspase-3 zymogen protein (32-kDa) with the appearance of its 20-kDa subunit as well as a cleaved 89-kDa fragment of 116-kDa PARP when apoptosis occurred. The expression of Bcl-2 was down-regulated remarkably accompanied by the disruption of the mitochondrial membrane potential (delta(psi)m). The anti-proliferative and apoptosis-inducing effects by oridonin in fresh APL cells were also found remarkably using Trypan Blue dye exclusion method and Wright's staining. We concluded that oridoning has significant anti-proliferative and apoptosis-inducing effects on NB4 cells by activation of caspase-3 and cleavage of PARP as well as by down regulation of Bcl-2 and disruption of the delta(psi)m. Furthermore, oridonin demonstrated apparent cell growth inhibition effects on fresh APL cells in vitro. The results indicated that oridonin may serve as a potential anti-leukemia reagent.
体外研究了冬凌草甲素对急性早幼粒细胞白血病（APL）细胞的抗增殖作用及其机制。用不同浓度的冬凌草甲素处理NB4细胞以及从APL患者获得的在培养基中培养的新鲜白血病细胞。通过MTT法、流式细胞术（FCM）和蛋白质免疫印迹分析评估细胞生长抑制、凋亡及相关途径。数据显示，冬凌草甲素（超过16 μmol/L）可通过诱导凋亡抑制NB4细胞的生长。细胞暴露于冬凌草甲素48小时后，用电子显微镜和DNA片段化分析非常清楚地观察到细胞凋亡的明显变化；蛋白质免疫印迹显示，凋亡发生时，caspase-3酶原蛋白（32 kDa）裂解，出现其20 kDa亚基以及116 kDa PARP的89 kDa裂解片段。Bcl-2的表达明显下调，同时线粒体膜电位（Δψm）破坏。使用台盼蓝拒染法和瑞氏染色法也发现冬凌草甲素对新鲜APL细胞具有显著的抗增殖和诱导凋亡作用。我们得出结论，冬凌草甲素通过激活caspase-3和裂解PARP以及下调Bcl-2和破坏Δψm，对NB4细胞具有显著的抗增殖和诱导凋亡作用。此外，冬凌草甲素在体外对新鲜APL细胞表现出明显的细胞生长抑制作用。结果表明，冬凌草甲素可能是一种潜在的抗白血病试剂。
