槲皮素-AAPH氧化产物结构鉴定及其对HepG2细胞氧化还原状态的影响

his study is aimed to explore the potential mechanism of prooxidant tendency of quercetin with high concentration. In this study, quercetin was mixed with APPH as oxidant under 37℃ for 4h. The structural characterization were analyzed by UV scan and LC-MS. The chromatogram shows peaks eluting at 294nm after 12h reaction and the structural analysis result shows that mixture of four oxidation products were obtained in the reaction system. HepG2 cells were treated with reaction product of quercetin -AAPH and incubated for 24h. The result shows that Quercetin oxidation products with high concentration (100μM) elevated the ROS and MDA generation，reduced cell viability, T-AOC, CAT, GSH-Px and SOD and GSH/GSSG activity in a dose-dependent manner. Nrf2，NQO-1、Prdx expression level was down-regulated and Keap-1、Nox-2、Cox-2 expression level was up-regulated in the meanwhile. These findings indicates that quercetin could act as prooxidant via its oxidation products to prompt HepG2 cells to generate more oxidative stress.