Department of Neurology, the Second Affiliated Hospital of Harbin Medical University, Harbin 150086, P. R. China.
Mol Cells. 2017 Nov 30;40(11):837-846. doi: 10.14348/molcells.2017.0084. Epub 2017 Oct 27.
As a component of the neurovascular unit, cerebral smooth muscle cells (CSMCs) are an important mediator in the development of cerebral vascular diseases such as stroke. Epoxyeicosatrienoic acids (EETs) are the products of arachidonic acid catalyzed by cytochrome P450 epoxygenase. EETs are shown to exert neuroprotective effects. In this article, the role of EET in the growth and apoptosis of CSMCs and the underlying mechanisms under oxygen glucose deprivation (OGD) conditions were addressed. The viability of CMSCs was decreased significantly in the OGD group, while different subtypes of EETs, especially 14,15-EET, could increase the viability of CSMCs under OGD conditions. RAPA (serine/threonine kinase Mammalian Target of Rapamycin), a specific mTOR inhibitor, could elevate the level of oxygen free radicals in CSMCs as well as the anti-apoptotic effects of 14,15-EET under OGD conditions. However, SP600125, a specific JNK (c-Jun N-terminal protein kinase) pathway inhibitor, could attenuate oxygen free radicals levels in CSMCs as well as the anti-apoptotic effects of 14,15-EET under OGD conditions. These results strongly suggest that EETs exert protective functions during the growth and apoptosis of CSMCs, via the JNK/c-Jun and mTOR signaling pathways in vitro. We are the first to disclose the beneficial roles and underlying mechanism of 14,15-EET in CSMC under OGD conditions.
作为神经血管单元的一个组成部分,脑平滑肌细胞(CSMCs)是中风等脑血管疾病发展的重要介质。环氧化物水解酶(epoxygenase)催化花生四烯酸生成的表氧化物脂肪酸(EETs)具有神经保护作用。本文探讨了 EET 在氧葡萄糖剥夺(OGD)条件下 CSMC 生长和凋亡中的作用及其潜在机制。在 OGD 组中,CSMCs 的活力显著下降,而不同类型的 EETs,特别是 14,15-EET,可在 OGD 条件下增加 CSMCs 的活力。雷帕霉素(mTOR)的一种特异性抑制剂 RAPA 可提高 CSMCs 中的氧自由基水平以及 14,15-EET 在 OGD 条件下的抗凋亡作用。然而,特异性 JNK(c-Jun N-末端蛋白激酶)通路抑制剂 SP600125 可降低 CSMCs 中的氧自由基水平以及 14,15-EET 在 OGD 条件下的抗凋亡作用。这些结果强烈表明,EETs 通过体外 JNK/c-Jun 和 mTOR 信号通路发挥保护作用,在 CSMC 的生长和凋亡中发挥保护作用。我们首次揭示了 14,15-EET 在 OGD 条件下对 CSMC 的有益作用及其潜在机制。