儿茶素及其聚合物对乙醇引起的小鼠纹状体抗坏血酸和羟自由基释放的影响(英文)

Effects of Catechin and Its Polymers on Ethanol- induced Ascorbic Acid and Hydroxyl Radical Release in Mouse Striatum

目的:研究葡萄籽儿茶素及其聚合物对乙醇引起的小鼠纹状体羟自由基产生和内源性抗坏血酸释放的影响。方法:应用脑微透析技术结合高效液相色谱电化学检测技术。结果:儿茶素及其低、高聚体(50,100mg/kg,i.p.)对纹状体抗坏血酸和羟自由基(以2.3-,2.5-DHBA表示)的基础水平没有明显的影响,但均可以延长乙醇(4.0g//kg,i.p.)引起的小鼠纹状体内源性抗坏血酸的释放,并抑制乙醇引起的纹状体羟自由基的产生。在作用强度上,儿茶素高于其聚合物,低聚体的作用强于高聚体。上述结果表明,葡萄籽中的儿茶素及其聚合物可以通过促进纹状体内源性抗坏血酸的释放,进而抑制乙醇引起的羟自由基产生。结论:上述结果提示葡萄籽儿茶素及其聚合物可以抵抗脑内氧化应激损伤,具有一定的神经保护作用。

AIM:To investigate the effects of catechin and its polymers isolated from grape seeds on ethanol-induced hydroxyl radical generation and endogenous ascorbic acid release in mouse striatum. METHOD: Brain microdialysis coupled to HPLC with electrochemical detection was employed. RESULT: It was found that catechin, low-polymers of catechin, high-polymers of catechin, at the dose of 50 and 100 mg/kg, i. p. , had no significant effects on basal ascorbic acid release and hydroxyl radical (shown as 2.3- and 2.5-DHBA) formation. All constituents could significantly lengthen the course of ethanol (4.0g/kg, i.p.) -induced endogenous ascorbic acid release and inhibit hydroxyl radical generation in mouse striatum. Catechin was more effective than its polymers, and low-polymers of catechin were more effective than high-polymers. CONCLUSION: These results provide evidence that catechin and its polymers from grape seeds inhibit ethanol-induced hydroxyl radical formation by stimulating endogenous ascorbic acid release in the striatum, which might consist of one of important mechanisms of action of catechin for its neuroprotective activities against oxidative damage in brain.