槲皮素对脑组织受自由基损伤的保护作用

目的：研究槲皮素（quercetin,Que）对脑组织受自由基损伤的保护作用。方法：采用Fenton反应诱导大鼠脑组织匀浆的脂质过氧化模型和结扎小鼠大脑中动脉（MCAO）致脑梗塞模型;分别测定了槲皮素在这两种体内外脑组织模型中的抗氧化作用。结果：在体外,槲皮素可剂量依赖性地抑制Fenton反应导致的脑组织匀浆中过氧化脂质（LPO）的生成,其IC50为1.7×10-4mol/L。在体内,腹腔注射20mg/kg的槲皮素可有效改善MCAO小鼠的运动功能障碍（P〈0.01）,缩小脑梗塞范围（抑制率为24%,P〈0.01）,减少脑组织中LPO的生成（P〈0.01）及提高SOD和GSH-PX的活性（P〈0.05）。结论：槲皮素对体内外的脑组织有一定程度的抗氧化作用。

Protective effect of Quercetin on Brain injury by free radicals

AIM：To evaluate the antioxidant effects of quercetin（Que） on brain tissue.METHOD：In vitro and in vivo models were applied,ie.Fenton reaction induced lipid peroxidation in rat brain homogenates,and the middle cerebral artery occlusion（MCAO） in mice.Then the antioxidant effects of Que on brain tissue were assayed.RESULT：In vitro,the IC50 of Que of inhibiting the production of lipid peroxides（LPO） in rat brain homogenate was 1.7 × 10-4 mol/L.Que exert the effect in an dose-dependant manner.In vivo,ip.20mg/kg Que ameliorate the motor dysfunction of MCAO mice effectively（P 0.01）,reduce the cerebral infarcted size（inhibitory rate is 16%）,decrease the LPO production（9.45 ± 0.21nmol/mg pro.vs 9.87 ± 0.19nmol/mg pro.in model group,P 0.01）,increase the activity of SOD（19.7 ± 1.1 U/mg pro.vs 18.3 ± 1.3 U/mg pro.in model group,P 0.05） and GSH-PX（23.8 ± 1.9 U/mg pro.vs 21.4 ± 2.0 U/mg pro.in model group,P 0.05） in brain tissue.CONCLUSION：Que possess antioxidant effect on brain tissue both in vitro and in vivo.