葡萄籽原花青素对小鼠脑缺血再灌注损伤的保护作用

背景:研究发现,葡萄籽原花青素具有清除自由基、抗心肌缺血再灌注损伤、增强实验动物学习、记忆等的能力。但其对小鼠脑缺血再灌注损伤的作用尚不十分清楚。目的:观察葡萄籽原花青素对脑缺血再灌注小鼠脑中总抗氧化能力、一氧化氮合酶活性及丙二醛含量的影响,探讨葡萄籽原花青素的脑保护作用。设计:完全随机分组设计,对照实验。单位:锦州医学院病理生理教研室和机能中心实验室,锦州医学院附属第一医院神经内科。材料:实验于2004-03/08在锦州医学院机能中心实验室完成。选用锦州医学院动物实验中心提供的昆明种小鼠40只。随机分为5组:对照组、模型组、低剂量葡萄籽原花青素治疗组、高剂量葡萄籽原花青素治疗组及尼莫地平治疗组,每组8只。方法:①建立脑缺血再灌注模型:动物乙醚麻醉,颈正中切口,两边颈总动脉用微动脉夹夹闭30min后去除动脉夹,恢复动脉血流。对照组只分离两边颈总动脉,不夹闭。②模型组和对照组:在夹闭小鼠双侧颈总动脉同时及再灌注后每隔24h分别按40mg/kg剂量腹腔注射蒸馏水、低和高剂量葡萄籽原花青素组及尼莫地平组按10,40,2mg/kg剂量腹腔注射葡萄籽原花青素及尼莫地平。再灌注72h后断头取脑,采用化学比色法测定一氧化氮合酶的酶活力,总抗氧化能力及丙二醛含量。③组间计量资料差异比较采用t检验。主要观察指标:各组大鼠脑组织中总抗氧化能力、一氧化氮合酶活性及丙二醛含量。结果:进入结果分析小鼠40只,每组8只。①总抗氧化能力:模型组明显低于对照组(t=8.145,P=0.000),而低、高剂量葡萄籽原花青素治疗组及尼莫地平治疗组又明显高于模型组(t=6.313,8.956,4.14,P<0.01)。②一氧化氮合酶活性:模型组明显高于对照组(t=12.541,P<0.01),而低、高剂量葡萄籽原花青素治疗组及尼莫地平治疗组又明显低于模型组(t=2.231,8.956,7.260,P<0.05～0.01)。③丙二醛含量:模型组明显高于对照组(t=7.883,P<0.01),高剂量葡萄籽原花青素治疗组及尼莫地平治疗组又明显低于模型组(t=5.234,4.518,P<0.01)。结论:葡萄籽原花青素可能通过提高机体总抗氧化能力,对抗脂质过氧化以及降低脑组织中一氧化氮合酶活性而发挥脑保护作用。

Protective effects of grape seed proanthocyanidins on cerebral ischemia-reperfusion injury in mice

BACKGROUND: Researches find that grape seed proanthocyanidins (GSP) can eliminate free radicals, protect heart against ischemia-reperfusion injury and enhance learning and memory abilities in experimental animal, but their effects on the cerebral ischemia-reperfusion injury remain unclear.OBJECTIVE: To study the protective effects of proanthocyanidins derived from grape seeds on the cerebral ischemic reperfused brain by measuring the total antioxidative capacity (T-AOC), nitric oxide synthase activities and malondialdehyde (MDA) content in brain tissue of mice.DESIGN: A completely randomized and controlled study.SETTING: Department of Pathophysiology and Functional Central Laboratory, Jinzhou Medical College; Department of Neurology, the First Affiliated Hospital of Jinzhou Medical College.MATERIALS: The experiment was conducted in the Department of Functional Central Laboratory, Jinzhou Medical College from March to August 2004. Forty Kunming mice, provided by the Experimental Animal Center, Jinzhou Medical College, were randomly divided into five groups: sham control group, cerebral ischemia-reperfusion group (IR group) and cerebral ischemia-reperfusion treated with low or high dose of GSP or nimdipine (IR+GSP or IR+Nim) group with eight mice in each group.METHODS: ① Animal model establishment: The animals were anesthetized with ether. Then they were incised through median incision of the neck. The bilateral common carotid arteries were then occluded by microaneurysm clips for 30 minutes. After removing the clips, return of flow was visualized in the arteries. ② Model group and control group:The mice in low or high dose of GSP treated group or nimdipine treated group were injected GSP or nimdipine 10, 40, 2 mg/kg body mass respectively during the common carotid arteries occlusion and again at 24hours after reperfusion, while the mice in sham control group were injected the same volume distilled water with 40 mg/kg body mass. After 72-hour reperfusion, nitric oxide synthase activities, the total antioxidative capacity and MDA content in brain tissue of mice in each group were detected with chemical chromatometry. ③ The results were assessed by t test.MAIN OUTCOME MEASURES: Nitric oxide synthase activities, the total antioxidative capacity and MDA content in brain tissue of mice in each group were detected.RESULTS: Data of forty Kunming mice was entered the results analysis without any loss. ① Total antioxidative capacity: Total antioxidative capacity in cerebral ischemia-reperfusion group was obvious lower than that in the sham control group (t=8.145, P=0.000) while total antioxidative capacity in low or high dose of GSP treated group and nimdipine treated group was obvious higher than that in the cerebral ischemia-reperfusion group (t=6.313, 8.956, 4.14, P ＜ 0.01). ② Nitric oxide synthase activities: Nitric oxide synthase activities in cerebral ischemia-reperfusion group was obvious higherthan that in the sham control group (t=12.541, P ＜ 0.01), while nitric oxide synthase activities in low or high dose of GSP treated group and nimdipine treated group was obvious lower than that in the cerebral ischemia-reperfusion group (t=2.231, 8.956, 7.260, P ＜ 0.05-0.01). ③ MDA content: MDA content in cerebral ischemia-reperfusion group was obvious higher than that in the sham control group (t=7.883, P ＜ 0.01), while high dose of GSP treated group and nimdipine treated group was obvious lower than that in the cerebral ischemia-reperfusion group (t =5.234,4.518, P ＜ 0.01).CONCLUSION: GSP exerted a protective effect on the cerebral ischemic reperfused brain by enhancing total antioxidative capacity and reducing lipid peroxidantion and nitric oxide synthase activities.