Effect of Flavonoids from Apple Pericarp on Antioxidant Functions in D-Galactose-Induced Aging Mice

Objective: This study aimed to examine the antioxidant effect of total flavonoids from apple pericarp(FAP) in D-galactose-induced aging mice. Methods: The aging model was established by hypodermic injection of D-galactose. Fifty healthy Kunming mice were chosen and randomly divided into five groups(n=10, half male and half female): normal control, model control, low-(50 mg/kg), middle-(100 mg/kg) and high-dose(200 mg/kg) FAP treatment groups. From the sixteenth day after the injection, the mice from the three treatment groups were intragastrically administrated with FAP for 45 successive days. The learning and memory ability of mice were tested using the darkness-avoidance and Morris water maze methods on the forty-sixth day. Then, the mice were killed, and blood, brain, liver, heart and kidney tissues were collected for the measurement of MDA contents, and SOD activities and GSH-Px activities. Results: Compared with the normal control group, the learning and memory ability of the mice in the model control group were decreased; the MDA contents of brain, liver, kidney and blood except for heart tissue were increased significantly(P0.05), whereas the activities of SOD and GSH-Px were decreased significantly(P0.05). Compared with the model control group, except for the activities of blood SOD and GSH-Px in the mice from the high- and low-dose groups as well as heart GSH-Px activity in the mice from the low-dose group, which were not significantly enhanced(P0.05), both enzyme activities revealed a significant increase in all other investigated tissues(P0.05). When comparing each dose group with the normal control group, there were no significant differences in the various parameters for the middle-dose group, yet the low- and high-dose groups indicated a significant increase in MDA content and a significant decrease in SOD and GSH-Px activities(P 0.05). Conclusion: Orally administered FAP improve antioxidant functions in aging mice, showing a dose-effect relationship.