Effects of quercetin on hemoglobin-dependent redox reactions: relationship to iron-overload rat liver injury
Effects of quercetin on hemoglobin-dependent redox reactions: relationship to iron-overload rat liver injury
复制标题
槲皮素对血红蛋白依赖性氧化还原反应的影响：与铁过载大鼠肝损伤的关系
DOI：
10.1080/10286020.2013.838952
复制
发表时间：
2013-12-01
影响因子：
1.7
通讯作者：
Peng, Yi-Yuan
中科院分区：
文献类型：
--
作者：
Lu, Nai-Hao;Chen, Chao;Peng, Yi-Yuan
黄酮类化合物被广泛报道用于保护铁超负荷疾病中的肝损伤，其治疗作用的机制依赖于其抗氧化作用，包括清除自由基和金属螯合作用。在本研究中，与铁含量的显著下降相反，低饲料(0.3%，w/w)中的槲皮素(Qu)对蛋白质羰基的形成具有促进氧化的作用，而对铁超载大鼠的肝损伤没有明显的作用。此外，还研究了Qu对依赖于Hb的氧化还原反应(即Hb及其细胞毒性铁基中间体的氧化稳定性和Hb诱导的蛋白质氧化)的抗氧化和促氧化活性，以说明Qu处理后铁超载大鼠蛋白质氧化水平的升高。结果表明，Qu与Hb反应生成超氧化物()和过氧化氢(H_2O_2)。然而，Qu在两相动力学反应中有效地将铁基中间体还原为Hb铁。此外，Qu在低浓度时可显著加重HB-H_2O_2诱导的蛋白质氧化，在高浓度时具有保护作用。因此，与传统的Qu抗氧化机制不同，Qu在体外对Hb氧化还原反应的双重作用，可能为揭示Qu在铁超载疾病中的生理和药理意义提供新的见解。
Flavonoids have been widely reported to protect liver injury in iron-overload diseases, where the mechanism of this therapeutic action is dependent on their antioxidant effects, including free radical scavenging and metal-chelating. In this study, in contrast to the significant decrease in iron content, quercetin (Qu) from lower diet (0.3%, w/w) showed pro-oxidant ability on protein carbonyl formation and exhibited unobvious effect on iron-overload rat liver injury. Furthermore, the anti- and pro-oxidant activities of Qu on hemoglobin (Hb)-dependent redox reactions (i.e. the oxidative stability of Hb and its cytotoxic ferryl intermediate, Hb-induced protein oxidation) were investigated to illustrate the elevated protein oxidation in lower Qu-treated iron-overload rat. It was found that superoxide () and hydrogen peroxide (H2O2) were generated during the reaction between Qu and Hb. Qu, however, effectively reduced ferryl intermediate back to ferric Hb in a biphasic kinetic reaction. Moreover, Qu could significantly aggravate Hb–H2O2-induced protein oxidation at low concentrations and exhibit protective effects at high concentrations. Different from the classic antioxidant mechanisms of Qu, the dual effects on Hb redox reactions in vitro, therefore, may provide new insights into the physiological and pharmacological implications of Qu with iron-overload disease.