银杏叶提取物GBE50对缺氧致内皮细胞功能的影响

目的初步探讨缺氧对人脐静脉内皮细胞功能的影响，以及银杏叶提取物GBE50在其中的作用。方法应用流式细胞技术、TUNEL、RT—PCR及Western blot等方法，探讨缺氧及GBE50对内皮细胞功能的影响。结果缺氧干预内皮细胞24h后，细胞活性氧（reactive oxygen species，ROS）水平及早期、晚期凋亡率均明显增加，伴随内皮素（endothelin-1，ET-1）mRNA水平及内皮型一氧化氮合成酶（endothelial oxide synthase，eNOS）蛋白水平的升高。缺氧前4h给予GBE50干预后发现，GBE5025μg／ml时可显著降低细胞早期及晚期凋亡率及ET-1 mRNA水平（P〈0．05），部分降低因缺氧导致的ROS水平及eNOS蛋白表达的增高（P〉0．05）。结论缺氧可导致血管内皮功能障碍，而GBE50可部分或显著逆转缺氧所致的内皮功能障碍，GBE50对缺氧所致的内皮功能障碍有一定的保护作用。

Effects of Ginkgo Biloba Extract 50 on Hypoxia Induced Endothelial Dysfunction

OBJECTIVE: To preliminarily investigate the influence of hypoxia on human umbilical vein endothelial cells (HUVECs), and the effect of Ginkgo biloba extract 50 (GBE50) on it. METHODS: Flow cytometry, TUNEL, RT-PCR, Western blot, etc. were applied, to study the effect of hypoxia and GBE50 on endothelial cells. RESULTS: After being interfered by hypoxia for 24 h, the levels of reactive oxygen species (ROS) in HUVECs and the apoptotic rate either in the early or in the late stage significantly increased, and accompanied with the increased levels of endothelin-1 mRNA (ET-1) and endothelial oxide synthase (eNOS) protein. However, when HUVECs were pretreated with GBE50 (25 microg/ml) 4 h before hypoxia, the apoptotic rate in the early or late stage and expression of ET-1 mRNA significantly decreased (P < 0.05), and the heightened ROS level and eNOS expression partially decreased (P > 0.05). CONCLUSION: Hypoxia can induce endothelial dysfunction, which could be partially or significantly reversed by GBE50, it shows a certain protective effect on hypoxia induced endothelial dysfunction.