目的 研究紫檀茋对脑缺血再灌注大鼠的脑保护作用，并考察其对血管内皮间质过度转化与蛋白激酶B/糖原合成激酶-3β（protein kinase B/glycogen synthesizing kinase-3β，Akt/GSK-3β）通路的影响。方法 建立脑缺血再灌注大鼠模型，给予紫檀茋和硫酸氢氯吡格雷片干预6 d后，检测大鼠神经功能缺损程度；采用ELISA法检测各组大鼠血清血小板活化因子（platelet activating factor，PAF）、血小板源性CD40配体（CD40L）和血小板P选择素（P-slelctin，CD62P）水平；采用试剂盒检测各组大鼠脑组织超氧化物歧化酶（superoxide dismutase，SOD）活性和丙二醛（malondialdehyde，MDA）水平；采用苏木素-伊红（HE）染色法观察各组大鼠脑皮质病理变化；采用免疫荧光染色法检测各组大鼠脑血管内皮和间质标志物血小板-内皮细胞黏附分子-1（platelet endothelial cell adhesion molecule-1，PECAM-1，又名CD31）、α-平滑肌肌动蛋白（α-smooth muscle actin，α-SMA）表达；采用Western blotting法检测各组大鼠脑血管CD31、α-SMA和脑皮质Akt和GSK-3β蛋白表达情况；采用免疫组化法检测各组大鼠脑皮质Akt和GSK-3β蛋白表达。结果 与假手术组比较，模型组大鼠神经功能缺损评分显著升高（P＜0.05）；血清PAF、CD40L和CD62P水平显著升高（P＜0.05）；脑组织SOD活性显著降低，MDA水平升高（P＜0.05）；脑皮质细胞形态破坏，呈空泡样坏死，细胞间隙增大，染色变浅，残存细胞体积缩小，细胞核固缩、深染，细胞边界不清；脑血管CD31表达减弱，α-SMA表达增强；脑血管CD31和脑皮质p-Akt、p-GSK-3β蛋白表达水平显著降低（P＜0.05），脑血管α-SMA蛋白表达水平显著升高（P＜0.05）。与模型组比较，各给药组大鼠神经功能缺损评分显著降低（P＜0.05）；血清PAF、CD40L和CD62P水平降低（P＜0.05）；脑组织SOD活性升高（P＜0.05），MDA水平降低（P＜0.05）；脑皮质细胞形态、排列、细胞核清晰度以及间质染色均匀度等均改善；脑血管CD31表达增强，α-SMA表达减弱；脑血管CD31和脑皮质p-Akt、p-GSK-3β蛋白表达水平显著升高（P＜0.05），脑血管α-SMA蛋白表达水平显著降低（P＜0.05）。结论 紫檀茋对脑缺血再灌注大鼠具有脑保护作用，可抑制血管内皮-间质过度转化，其作用机制可能与激活Akt/GSK-3β通路有关。

Objective To study the cerebral protective effect of pterostilbene on cerebral ischemia-reperfusion rats, and investigate its effect on vascular endothelial mesenchymal transition and protein kinase B/glycogen synthesizing kinase-3β (Akt/GSK-3β) pathway. Methods A rat model of cerebral ischemia-reperfusion was established, and after 6 d of intervention with pterostilbene and clopidogrel hydrogen sulfate tablets, degree of neurological deficit in rats was detected; Platelet activating factor (PAF), platelet-derived CD40 ligand (CD40L) and platelet P-selectin (CD62P) levels in serum were detected by ELISA; Kits were used to detect superoxide dismutase (SOD) activity and malondialdehyde (MDA) level in brain tissue of rats in each group; Hematoxylin-eosin (HE) staining was used to observe the pathological changes of cerebral cortex of rats in each group; Immunofluorescence staining was used to detect the cerebral vascular endothelial and interstitial markers platelet endothelial cell adhesion molecule-1 (PECAM-1, also known as CD31) and α-smooth muscle actin (α-SMA) expressions of rats in each group; Western blotting was used to detect CD31 and α-SMA protein expressions in cerebrovascular, Akt and GSK-3β protein expressions in cerebral cortex of rats; Akt and GSK-3β expressions in cerebral cortex of rats in each group were detected by immunohistochemistry. Results Compared with sham group, neurological deficit score of rats in model group was significantly increased (P < 0.05); Levels of PAF, CD40L and CD62P in serum were significantly increased (P < 0.05); SOD activity in brain tissue was significantly decreased, and MDA level was increased (P < 0.05); Cerebral cortical cells were morphologically damaged, showing vacuolar necrosis, intercellular space was increased, staining was lighted, residual cell volume was reduced, nuclei were pyknotic and hyperchromatic, and cell boundaries were unclear; CD31 expression in cerebral blood vessels was weakened, α-SMA expression was enhanced; CD31 protein expression in cerebrovascular, p-Akt and p-GSK-3β protein expressions in cerebral cortex of rats were significantly decreased (P < 0.05), α-SMA protein expression in cerebrovascular was significantly increased (P < 0.05). Compared with model group, neurological deficit score of rats in each administration group were significantly decreased (P < 0.05); Levels of PAF, CD40L and CD62P in serum were decreased (P < 0.05); SOD activity in brain tissue was increased (P < 0.05), MDA level of cerebral cortex was decreased (P < 0.05); Morphology, arrangement, nuclear clarity and interstitial staining uniformity of cerebral cortex were improved; CD31 expression in cerebral blood vessels was increased, and α-SMA expression was decreased; CD31 protein expression in cerebrovascular, p-Akt and p-GSK-3β protein expressions in cerebral cortex of rats were significantly increased (P < 0.05), α-SMA protein expression in cerebrovascular was significantly decreased (P < 0.05). Conclusion Pterostilbene has cerebral protective effect on cerebral ischemia-reperfusion rats, and can inhibit the excessive transition of vascular endothelium to mesenchyme, and its mechanism may be related to the activation of Akt/GSK-3β pathway.

R285.5

河南省科技发展计划项目（192102310349）