Division of Clinical Neuroscience, Center for Forensic Mental Health, Chiba University, Chiba, Japan.
PLoS One. 2011 Mar 1;6(3):e17431. doi: 10.1371/journal.pone.0017431.
Cilostazol, a type-3 phosphodiesterase (PDE3) inhibitor, has become widely used as an antiplatelet drug worldwide. A recent second Cilostazol Stroke Prevention Study demonstrated that cilostazol is superior to aspirin for prevention of stroke after an ischemic stroke. However, its precise mechanisms of action remain to be determined. Here, we report that cilostazol, but not the PDE3 inhibitors cilostamide and milrinone, significantly potentiated nerve growth factor (NGF)-induced neurite outgrowth in PC12 cells. Furthermore, specific inhibitors for the endoplasmic reticulum protein inositol 1,4,5-triphosphate (IP(3)) receptors and several common signaling pathways (PLC-γ, PI3K, Akt, p38 MAPK, and c-Jun N-terminal kinase (JNK), and the Ras/Raf/ERK/MAPK) significantly blocked the potentiation of NGF-induced neurite outgrowth by cilostazol. Using a proteomics analysis, we identified that levels of eukaryotic translation elongation factor eEF1A1 protein were significantly increased by treatment with cilostazol, but not cilostamide, in PC12 cells. Moreover, the potentiating effects of cilostazol on NGF-induced neurite outgrowth were significantly antagonized by treatment with eEF1A1 RNAi, but not the negative control of eEF1A1. These findings suggest that eEF1A1 and several common cellular signaling pathways might play a role in the mechanism of cilostazol-induced neurite outgrowth. Therefore, agents that can increase the eEF1A1 protein may have therapeutic relevance in diverse conditions with altered neurite outgrowth.
西洛他唑是一种 3 型磷酸二酯酶（PDE3）抑制剂，已在全球范围内广泛用作抗血小板药物。最近的第二次西洛他唑预防中风研究表明，西洛他唑在预防缺血性中风后中风方面优于阿司匹林。然而，其确切的作用机制仍有待确定。在这里，我们报告西洛他唑（而不是 PDE3 抑制剂西洛酰胺和米力农）可显著增强 PC12 细胞中神经生长因子（NGF）诱导的神经突生长。此外，内质网蛋白肌醇 1,4,5-三磷酸（IP（3））受体和几种常见信号通路（PLC-γ、PI3K、Akt、p38 MAPK 和 c-Jun N-末端激酶（JNK）和 Ras/Raf/ERK/MAPK）的特异性抑制剂显著阻断了西洛他唑对 NGF 诱导的神经突生长的增强作用。通过蛋白质组学分析，我们发现西洛他唑处理可显著增加 PC12 细胞中真核翻译延伸因子 eEF1A1 蛋白的水平，但西洛酰胺则没有。此外，用 eEF1A1 RNAi 处理可显著拮抗西洛他唑对 NGF 诱导的神经突生长的增强作用，但 eEF1A1 的阴性对照则没有。这些发现表明，eEF1A1 和几种常见的细胞信号通路可能在西洛他唑诱导的神经突生长机制中发挥作用。因此，增加 eEF1A1 蛋白的药物可能在神经突生长改变的多种情况下具有治疗相关性。
