Wagner Caroline, Fachinetto Roselei, Dalla Corte Cristiane Lenz, Brito Verônica Bidinotto, Severo Diego, de Oliveira Costa Dias Gilvan, Morel Ademir F, Nogueira Cristina W, Rocha João B T
Centro de Ciências Naturais e Exatas, Departamento de Química, Programa de Pós-Graduação Bioquímica Toxicológica, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil.
Brain Res. 2006 Aug 30;1107(1):192-8. doi: 10.1016/j.brainres.2006.05.084. Epub 2006 Jul 7.
Reactive oxygen species have been demonstrated to be associated with a variety of diseases including neurodegenerative disorders. Flavonoid compounds have been investigated for their protective action against oxidative mechanisms in different in vivo and in vitro models, which seems to be linked to their antioxidant properties. In the present study, we examine the protective mechanism of quercitrin, a glycoside form of quercetin, against the production of TBARS induced by different agents. TBARS production was stimulated by the incubation of rat brain homogenate with Fe2+, Fe2+ plus EDTA, quinolinic acid (QA), sodium nitroprusside (SNP) and potassium ferricyanide ([Fe(CN)6]3-). Quercitrin was able to prevent the formation of TBARS induced by pro-oxidant agents tested; however, it was more effective against potassium ferricyanide ([Fe(CN)6]3-, IC50=2.5), than quinolinic acid (QA, IC50=6 microg/ml) and sodium nitroprusside (SNP, IC50=5.88 microg/ml) than Fe2+ (Fe2+, IC50=14.81 microg/ml), Fe2+ plus EDTA (Fe2+ plus EDTA, IC50=48.15 microg/ml). The effect of quercitrin on the Fenton reaction was also investigated (deoxyribose degradation). Quercitrin caused a significant decrease in deoxyribose degradation that was not dependent on the concentration. Taken together, the data presented here indicate that quercitrin exhibits a scavenger and antioxidant role, and these effects probably are mediated via different mechanisms, which may involve the negative modulation of the Fenton reaction and NMDA receptor.
活性氧已被证明与包括神经退行性疾病在内的多种疾病有关。黄酮类化合物已在不同的体内和体外模型中研究了其对氧化机制的保护作用,这似乎与其抗氧化特性有关。在本研究中,我们研究了槲皮素苷形式的槲皮苷对不同试剂诱导的硫代巴比妥酸反应物(TBARS)产生的保护机制。通过将大鼠脑匀浆与Fe2+、Fe2+加乙二胺四乙酸(EDTA)、喹啉酸(QA)、硝普钠(SNP)和铁氰化钾([Fe(CN)6]3-)孵育来刺激TBARS的产生。槲皮苷能够预防所测试的促氧化剂诱导的TBARS的形成;然而,它对铁氰化钾([Fe(CN)6]3-,IC50=2.5)的效果比对喹啉酸(QA,IC50=6微克/毫升)和硝普钠(SNP,IC50=5.88微克/毫升)更有效,比对Fe2+(Fe2+,IC50=14.81微克/毫升)、Fe2+加EDTA(Fe2+加EDTA,IC50=48.15微克/毫升)更有效。还研究了槲皮苷对芬顿反应(脱氧核糖降解)的影响。槲皮苷导致脱氧核糖降解显著降低,且不依赖于浓度。综上所述,此处呈现的数据表明槲皮苷具有清除剂和抗氧化作用,并且这些作用可能通过不同机制介导,这可能涉及对芬顿反应和N-甲基-D-天冬氨酸(NMDA)受体的负调节。