Involvement of catalase in the apoptotic mechanism induced by apigenin in HepG2 human hepatoma cells

► Antioxidant enzymes in the apoptotic mechanism induced by apigenin in HepG2 cells. ► Catalase downregulation play an essential role in apigenin-induced apoptosis. ► Catalase added to the culture medium partially protected apigenin-induced cell death. ► Direct involvement of H2O2 in the apoptotic mechanism induced by apigenin. ► Apigenin promotes GSH depletion and ROS generation, contributing to apoptosis.