Su Chun-Li, Lin Ting-Yu, Lin Chun-Nan, Won Shen-Jeu
Department of Nursing, Chang Jung Christian University, Gueiren, Tainan 711, Taiwan.
J Agric Food Chem. 2009 Jan 14;57(1):55-61. doi: 10.1021/jf802769g.
Bufotalin is one of the bufadienolides isolated from Formosan Ch'an Su, which is made of the skin and parotid glands of toads. Ingestion of toad venom results in severe morbidity and high mortality. Although Ch'an Su is clinically toxic, it has been used as an important traditional Chinese medicine for heart failure and pains. In this study, bufotalin-induced apoptosis in human hepatocellular carcinoma Hep 3B cells was investigated. The results indicate that externalization of phosphatidylserine, accumulation of sub-G(1) cells, fragmentation of DNA, and formation of apoptotic bodies were observed in bufotalin-treated Hep 3B cells. The signaling pathway might be via the activation of caspase-8, increase in mitochondrial tBid, disruption of mitochondrial membrane potential, and translocation of apoptosis-inducing factor (AIF). Active caspase-8 might activate caspase-9 and caspase-3 leading to the cleavage of nuclear PARP. Presence of AIF and cleaved PARP in the nuclei might lead to DNA fragmentation. Caspase-8 inhibitor (Z-IETD) or wide-ranging caspase inhibitor (Z-VAD) significantly suppressed the bufotalin-induced apoptosis, while the anti-Fas neutralization antibody had no effect. These data suggest that bufotalin-induced apoptosis in Hep 3B cells might involve caspases and AIF.
蟾酥灵是从台湾蟾酥中分离出的一种蟾蜍二烯羟酸内酯，台湾蟾酥由蟾蜍的皮肤和腮腺制成。摄入蟾蜍毒液会导致严重发病和高死亡率。尽管蟾酥在临床上有毒，但它一直被用作治疗心力衰竭和疼痛的重要传统中药。在本研究中，研究了蟾酥灵诱导人肝癌Hep 3B细胞凋亡的情况。结果表明，在经蟾酥灵处理的Hep 3B细胞中观察到磷脂酰丝氨酸外化、亚G1期细胞积累、DNA片段化以及凋亡小体形成。信号通路可能是通过激活半胱天冬酶-8、线粒体tBid增加、线粒体膜电位破坏以及凋亡诱导因子（AIF）易位。活性半胱天冬酶-8可能激活半胱天冬酶-9和半胱天冬酶-3，导致核聚（ADP-核糖）聚合酶（PARP）裂解。细胞核中存在AIF和裂解的PARP可能导致DNA片段化。半胱天冬酶-8抑制剂（Z-IETD）或广谱半胱天冬酶抑制剂（Z-VAD）显著抑制了蟾酥灵诱导的凋亡，而抗Fas中和抗体则没有效果。这些数据表明蟾酥灵诱导Hep 3B细胞凋亡可能涉及半胱天冬酶和AIF。
