Cytoprotective effects and mechanisms of quercetin, quercitrin and avicularin isolated from Lespedeza cuneata G. Don against ROS-induced cellular damage

The purpose of this study was to compare the anti-oxidative and cytoprotective effects of quercitrin and avicularin isolated from Lespedeza cuneata G. Don extract to those of quercetin, an aglycone of quercitrin, and avicularin. Quercetin had higher antioxidative activity and cell penetration ratio than its glycosides, resulting in greater cytoprotective effects against 1O2. The cytoprotective effects against cell damage seems to reflect 1O2 quenching rate, free radical and ROS scavenging activity, and cell permeability. Among them, cell permeability to block free radical initiation and chain reactions in cell membranes is considered to be the most important feature of cytoprotective activity.