Department of Neurology, Yonsei University College of Medicine, Seoul, Republic of Korea.
Brain Res. 2011 Sep 15;1412:73-8. doi: 10.1016/j.brainres.2011.07.018. Epub 2011 Jul 18.
Apoptosis signal-regulating kinase 1 (Ask1) is one of mitogen-activated protein kinase kinase kinase (MAPKKK) for cell differentiation and apoptosis. The aim of the present study is to evaluate whether RNA interference against Ask1 (Ask1-siRNA) down-regulates the expression of Ask1 and prevents apoptotic neuronal cell death after ischemia/reperfusion (I/R) in mice. Mice were subjected to intraluminal suture occlusion of the middle cerebral artery for 1h, followed by reperfusion. The Ask1-siRNA or a control-siRNA was introduced using osmotic pump intracerebroventricularly at 3days before I/R. The expression and mRNA of Ask1 were evaluated by Western blot and RT-PCR after I/R with time. Immunohistochemistry and TUNEL assay were also investigated to evaluate the effect of Ask1 on cerebral infarction by Ask1-siRNA treatment. The expression of Ask1 was increased significantly at 8h after I/R. The level of mRNA and protein of Ask1 down-regulated after treatment of Ask1-siRNA and subsequently cerebral infarction volume was reduced. Our results suggest the increased Ask1 expression induce apoptotic cell death after I/R. And we also demonstrated that Ask1-siRNA attenuates upregulation of Ask1, which was followed by the reduction of infarction in ischemic brain after I/R. Ask1-siRNA could represent a molecular target for prevention of ischemic stroke.
细胞凋亡信号调节激酶 1（Ask1）是细胞分化和凋亡的丝裂原活化蛋白激酶激酶激酶（MAPKKK）之一。本研究旨在评估针对 Ask1 的 RNA 干扰（Ask1-siRNA）是否下调 Ask1 的表达，并防止缺血/再灌注（I/R）后小鼠的凋亡性神经元细胞死亡。小鼠接受大脑中动脉腔内缝线阻塞 1 小时，然后再灌注。在 I/R 前 3 天，使用渗透泵通过侧脑室向小鼠体内导入 Ask1-siRNA 或对照-siRNA。通过 Western blot 和 RT-PCR 在 I/R 后随时间评估 Ask1 的表达和 mRNA。免疫组织化学和 TUNEL 检测也用于评估 Ask1-siRNA 处理对脑梗死的影响。在 I/R 后 8 小时，Ask1 的表达显著增加。Ask1-siRNA 处理后，Ask1 的 mRNA 和蛋白水平下调，随后 I/R 后脑梗死体积减少。我们的结果表明，Ask1 的表达增加会在 I/R 后诱导细胞凋亡死亡。我们还证明，Ask1-siRNA 可减弱 Ask1 的上调，随后减少 I/R 后缺血性脑内的梗死。Ask1-siRNA 可能成为预防缺血性中风的分子靶点。
