The Protective Effect of Epoxyeicosatrienoic Acids on Cerebral Ischemia/Reperfusion Injury is Associated with PI3K/Akt Pathway and ATP-Sensitive Potassium Channels
The Protective Effect of Epoxyeicosatrienoic Acids on Cerebral Ischemia/Reperfusion Injury is Associated with PI3K/Akt Pathway and ATP-Sensitive Potassium Channels
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DOI：
10.1007/s11064-014-1456-2
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发表时间：
2015-01-01
影响因子：
4.4
通讯作者：
Zhu, Yu-Lan
中科院分区：
文献类型：
--
作者：
Qu, You-Yang;Yuan, Mei-Yan;Zhu, Yu-Lan
环氧二十碳三烯酸（Epoxyeicosatrienoicacids，ESTs）是花生四烯酸的细胞色素P450表氧化酶代谢产物，具有神经保护作用。磷脂酰肌醇3-激酶（PI 3 K）/Akt和ATP敏感性钾通道（KATP）被认为是介导神经保护的重要因素。然而，关于EkA给药后PI 3 K/Akt和KATP通道在脑中的作用知之甚少。体外培养的大鼠脑微血管平滑肌细胞（SMCs）进行氧糖剥夺（OGD）4 h。复氧后观察14，15-EET对OGD诱导的细胞凋亡的影响。Western blot和实时荧光定量PCR检测脑微血管平滑肌细胞Kir6.1、KATP通道亚基SUR 2B和p-Akt的表达。在体内实验中，我们使用12-（3-金刚烷-1-基-脲基）-十二烷酸[AUDA，一种特异性可溶性环氧化物水解酶（sEH）抑制剂]来间接证实Ekaline的作用。在大脑中动脉阻塞（MCAO）之前，大鼠腹腔注射AUDA。检测缺血半暗带细胞凋亡及p-Akt、Kir6.1和SUR 2B的表达。结果表明，Eclase对脑缺血再灌注损伤具有保护作用，并上调缺血半暗带和OGD诱导的脑微血管平滑肌细胞p-Akt和Kir6.1的表达。在体外实验中，PI 3 K特异性抑制剂Wortmannin和KATP特异性抑制剂Glib可抑制这种保护作用。以上结果提示，E3对脑缺血再灌注损伤的保护作用与PI 3 K/Akt通路和KATP通道有关。此外，PI 3 K通路可能有助于介导脑微血管平滑肌细胞上的KATP通道。
Epoxyeicosatrienoic acids (EETs), the cytochrome P450 epoxygenase metabolite of arachidonic acid, have been demonstrated to have neuroprotective effect. Phosphatidylinositol 3-kinase (PI3K)/Akt and ATP-sensitive potassium (KATP) channels are thought to be important factors that mediate neuroprotection. However, little is known about the role of PI3K/Akt and KATP channels in brain after EETs administration. In vitro experiment, oxygen-glucose deprivation (OGD) was performed in cultured rat cerebral microvascular smooth muscle cells (SMCs) for 4 h. The effect of 14,15-EET on OGD induced cell apoptosis was examined after reoxygenation. Western blot and real-time PCR were used to analyze the expression of Kir6.1, SUR2B (two subunits of KATP channels) and p-Akt on cerebral microvascular SMCs. In vivo experiments, we use 12-(3-adamantan-1-yl-ureido)-dodecanoic acid [AUDA, a specific soluble epoxide hydrolase (sEH) inhibitor] to confirm the effect of EETs indirectly. Rats were injected intraperitoneally with AUDA before being subjected to middle cerebral artery occlusion (MCAO). We detected the apoptosis and the expression of p-Akt, Kir6.1 and SUR2B in ischemic penumbra. The results showed that EETs protect against cerebral ischemia/reperfusion (I/R) injury and upregulated the expression of p-Akt and Kir6.1 in both of ischemic penumbra and OGD induced cerebral microvascular SMCs. The protective effect was inhibited by Wortmannin (a specific PI3K inhibitor) and Glib (a specific KATP inhibitor) respectively in vitro experiment. In conclusion, these results suggested that the protective effect of EETs on cerebral I/R injury is associated with PI3K/Akt pathway and KATP channels. Furthermore, the PI3K pathway may contribute to mediating KATP channels on cerebral microvascular SMCs.