Protective effect of apple phlorizin on hydrogen peroxide-induced cell damage in HepG2 cells

Apple phlorizin has many biological activities, such as antioxidant and liver protection. The present study aimed to evaluate the roles of apple phlorizin against hydrogen peroxide (H2O2)-induced oxidative damage in HepG2 cells. In this study, treatment with apple phlorizin (100 and 150 mu g/ml) decreased the production of reactive oxygen species and alleviated apoptosis as well as DNA damage in H2O2-induced HepG2 cells. These effects were associated with the increased activity of antioxidant enzymes, enhanced the ARE-driven phase II antioxidant gene expression and its upstream Nrf2 protein expression, and decreased apoptosis-related gene expression. However, the phase II antioxidant gene expression and Nrf2 protein expression upregulated by phlorizin were reversed by Nrf2 shRNA transfection. These results showed that phlorizin relieves oxidative stress, DNA damage, and apoptosis in H2O2-induced HepG2 cells, at least partially, by regulating the expression of Nrf2 protein and apoptosis-related genes. Practical applications Apple phlorizin is a polyphenol compound extracted from apple or apple juice. This report highlighted a protective effect of phlorizin on antioxidant stress, DNA damage, and apoptosis in H2O2-induced HepG2 cells. These results suggested that phlorizin may be developed for functional foods.