Attenuation of caspase-3-dependent apoptosis by Trolox post-treatment of X-irradiated MOLT-4 cells
Attenuation of caspase-3-dependent apoptosis by Trolox post-treatment of X-irradiated MOLT-4 cells
复制标题
DOI：
10.1080/095530099140609
复制
发表时间：
1999-02-01
影响因子：
2.6
通讯作者：
Kuwabara, M
中科院分区：
文献类型：
--
作者：
Inanami, O;Takahashi, K;Kuwabara, M
目的：在人类白血病细胞系MOLT - 4中，就信号转导通路而言，研究了一种抑制脂质过氧化的抗氧化剂Trolox在辐照后处理与X射线诱导的细胞凋亡之间的关系。
材料和方法：在X射线照射后用Trolox处理的MOLT - 4细胞中，通过台盼蓝拒染试验、琼脂糖凝胶电泳和蛋白质印迹法检测细胞活力、DNA片段化、p53、BCL - 2、BAX、活化的应激活化蛋白激酶/ c - Jun氨基末端激酶（SAPK/JNK）、活化的半胱天冬酶 - 3的表达以及多聚（ADP - 核糖）聚合酶（PARP）的裂解情况。
结果：X射线照射后观察到染色细胞和梯状DNA裂解。辐照后用Trolox处理显著抑制了细胞死亡和DNA片段化。X射线照射后p53和活化的SAPK/JNK表达增加，产生了PARP片段和活化的半胱天冬酶 - 3片段。辐照后用Trolox处理减弱了这些与细胞凋亡相关的生物分子的X射线照射诱导的表达、片段化或活化。p53下游的BCL - 2和BAX的表达不受照射和Trolox处理的影响。此外，细胞死亡与半胱天冬酶 - 3有关，因为梯状DNA裂解被Ac - DEVD - CHO完全抑制，而不被Ac - YVAD - CHO、甲苯磺酰赖氨酰氯甲酮（TLCK）和苯甲基磺酰氟（PMSF）抑制。
结论：辐照后的事件如膜损伤诱导半胱天冬酶 - 3依赖性细胞凋亡，这可能由SAPK/JNK的激活介导，且与p53无关。
Purpose: The relationship between post-irradiation treatment with Trolox, an antioxidant that inhibits lipid peroxidation, and X-ray-induced apoptosis, with regard to signal transduction pathways, was examined in MOLT-4, a human leukaemia cell line.Materials and methods: In MOLT-4 cells treated with Trolox after X-irradiation, viability, DNA fragmentation, expression of p53 BCL-2, BAX, active SAPK/JNK, active caspase-3 and the cleavage of PARP were measured by the trypan blue exclusion test, agarose pel electrophoresis and Western blotting.Results: Stained cells and ladder-like DNA cleavage were observed after X-irradiation. Cell death and DNA fragmentation were significantly inhibited by the post-irradiation treatment with Trolox. The expression of p53 and active SAPK/JNK was increased after X-irradiation, and fragments of PARP and the activated fragment of caspase-3 were produced. Post-irradiation treatment with Trolox attenuated the X-irradiation-induced expression, fragmentation or activation of these apoptosis-related biomolecules. The expression of BCL-2 and BAX, which would occur downstream from p53, was not changed by irradiation and Trolox treatment. Furthermore, cell death was associated with caspase-3 because the ladder-like DNA cleavage was completely inhibited by Ac-DEVD-CHO but not Ac-YVAD-CHO, TLCK and PMSF.Conclusion. Post-irradiation events such as membrane damage induce caspase-3-dependent apoptosis, which might be mediated by the activation of SAPK/JNK and be independent of p53.