A cytotoxin isolated from Agkistrodon acutus snake venom induces apoptosis via Fas pathway in A549 cells
A cytotoxin isolated from Agkistrodon acutus snake venom induces apoptosis via Fas pathway in A549 cells
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DOI：
10.1016/j.tiv.2007.04.008
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发表时间：
2007-09-01
影响因子：
3.2
通讯作者：
Cui, Li
中科院分区：
文献类型：
--
作者：
Zhang, Liang;Cui, Li
ACTX-6是从尖吻蝮蛇蛇毒中分离的蛋白质，并在体外对多种癌细胞表现出细胞毒活性。本文对ACTX-6诱导细胞死亡的确切机制进行了探讨，发现ACTX-6可诱导细胞凋亡。Western blot和RT-PCR结果显示ACTX-6可诱导Fas和FasL蛋白表达。当Fas信号通路被Fas或FasL的中和抗体阻断时，ACTX-6诱导的细胞凋亡被抑制。还通过免疫沉淀检测DISC形成。这些结果提示Fas通路参与ACTX-6诱导的细胞凋亡。caspase-3、8、9活性的检测结果表明，caspase-9的激活也参与了ACTX-6诱导的细胞凋亡。Bid裂解和线粒体膜电位（Delta（psi m））的消散证实了线粒体的参与。ACTX-6是一种L-氨基酸氧化酶，可以氧化L-氨基酸产生过氧化氢。检测ACTX-6处理后细胞内活性氧的产生，活性氧清除剂过氧化氢酶可抑制ACTX-6诱导的细胞凋亡。Western blot分析显示，JNK在ACTX-6处理的细胞中被磷酸化，并且c-Jun也被激活。JNK抑制剂SP 600125可抑制ACTX-6诱导的细胞凋亡，过氧化氢酶可抑制JNK和c-Jun磷酸化。结论：JNK通路在ACTX-6诱导的细胞凋亡中起重要作用，ACTX-6引起的氧化应激是JNK激活的重要机制。(C)2007爱思唯尔有限公司保留所有权利。
ACTX-6 is a protein isolated from Agkistrodon acutus snake venom and demonstrated cytotoxic activity to various cancer cells in vitro. In this paper the exact mechanism in ACTX-6-induced cell death was investigated and it was found that ACTX-6 could induce cell apoptosis. The results of Western blot and RT-PCR showed that ACTX-6 could induce Fas and FasL protein expression. When Fas signaling pathway was blocked by neutralizing antibodies to Fas or FasL, ACTX-6-induced apoptosis was inhibited. DISC formation was also detected by immunoprecipitation. These results suggested that Fas pathway was involved in ACTX-6-induced apoptosis. The activities of caspase-3, 8 and 9 were assayed and the activation of caspase-9 demonstrated that mitochondrial pathway was also involved in ACTX-6-induced apoptosis. Bid cleavage and dissipation of mitochondrial membrane potential (Delta(psi m)) verified the involvement of mitochondria. ACTX-6 is an L-amino acid oxidase and can oxidize L-amino acid to generate hydrogen peroxide. The production of ROS in ACTX-6-treated cells was detected and the ROS scavenger catalase could inhibit ACTX-6-induced apoptosis. Western blot analysis showed that JNK was phosphorylated in ACTX-6-treated cells and c-Jun was also activated. JNK inhibitor SP600125 could inhibit ACTX-6-induced apoptosis and catalase could inhibit JNK and c-Jun phosphorylation. It could be concluded that JNK pathway was necessary in ACTX-6-induced apoptosis and the oxidative stress generated by ACTX-6 was responsible for the activation of JNK. (C) 2007 Elsevier Ltd. All rights reserved.