Critical role of ASK1 in the 6-hydroxydopamine-induced apoptosis in human neuroblastoma SH-SY5Y cells
Critical role of ASK1 in the 6-hydroxydopamine-induced apoptosis in human neuroblastoma SH-SY5Y cells
复制标题
DOI：
10.1111/j.1471-4159.2006.03730.x
复制
发表时间：
2006-04-01
影响因子：
4.7
通讯作者：
Shen, X
中科院分区：
文献类型：
--
作者：
Ouyang, MX;Shen, X
6-羟基多巴胺（6-OHDA）诱导的多巴胺能神经元细胞凋亡是帕金森病（PD）的常见细胞模型。凋亡信号调节激酶1（ASK 1）在该模型中的作用尚未得到很好的研究。我们观察到6-OHDA对人多巴胺能神经母细胞瘤SH-SY 5 Y细胞中ASK 1、p38和JNK的显著激活以及细胞凋亡的影响。过度表达激酶死亡突变体ASK 1（K709 M）或通过其小干扰RNA（siRNA）敲低内源性ASK 1，极大地抑制了这些激酶的激活和细胞凋亡。结果发现，p38和JNK的激活在ASK 1敲低的细胞中被抑制到与ASK 1几乎相同的程度，这表明激活的ASK 1几乎完全负责p38/JNK的激活。另外，通过过量表达p38的显性失活突变体或p38抑制剂SB 203580可以有效地阻止6-OHDA诱导的细胞凋亡，这表明启动程序性细胞死亡需要p38/JNK信号传导的激活。此外，通过用N-乙酰基-L-半胱氨酸预孵育细胞来抑制6-OHDA产生的活性氧（ROS），有效地抑制了6-OHDA诱导的ASK 1、p38和JNK的活化，并保护细胞免于凋亡。该研究清楚地显示了在所研究的PD模型中从6-OHDA产生ROS到通过激活ASK 1启动p38/JNK信号传导的途径。
6-Hydroxydopamine (6-OHDA)-induced apoptosis in dopaminergic neuronal cells is a common cell model of Parkinson's disease (PD). The role of apoptosis signal-regulating kinase 1 (ASK1) in this model has not been well studied. We observed significant activation of ASK1, p38 and JNK, as well as apoptosis in human dopaminergic neuroblastoma SH-SY5Y cells exposed to 6-OHDA. Over-expressing kinase-dead mutant ASK1(K709M) or knock-down of endogenous ASK1 by its small interfering RNA (siRNA) greatly suppressed activation of these kinases and apoptosis in the cells. It was found that the activation of p38 and JNK was suppressed to almost the same extent as that of ASK1 in the ASK1-knock-down cells, suggesting that activated ASK1 is almost totally responsible for activation of p38/JNK. It was also observed that the 6-OHDA-induced cell apoptosis could be effectively prevented by over-expressing the dominant-negative mutant of p38 or p38 inhibitor SB203580, demonstrating that activation of p38/JNK signalling is required for initiating the programmed cell death. Furthermore, suppression of the 6-OHDA-generated reactive oxygen species (ROS) by pre-incubation of cells with N-acetyl-l-cysteine effectively inhibited the 6-OHDA-induced activation of ASK1, p38 and JNK, and protected the cells from apoptosis. This study clearly shows the route from ROS generation by 6-OHDA to initiation of p38/JNK signalling via activation of ASK1 in the studied PD model.