D-α-Tocopheryl Succinate is a potent antioxidant tocopherol. At high concentrations it has been shown to trigger caspase-mediated apoptosis of certain cells and, at low concentrations, inhibit proliferation. Mechanistic studies suggest that this compound down-regulates the fibroblast growth factor receptor-1 (FGFR1). Other experiments report that D-α-Tocopheryl Succinate also targets ASK 1, GADD 45β, and MEK-4, three key components of stress-activated mitogen-activated protein kinase pathway.