Alpha-tocopherol (primary active form of vitamin E)

Vitamin E denotes a family of eight fat-soluble compounds—four tocopherols and four tocotrienols—of which alpha-tocopherol is the most biologically active form in humans. Vitamin E molecules act as chain-breaking antioxidants in lipid membranes, terminating the propagation of lipid peroxidation by scavenging lipid peroxyl radicals. The antioxidant activity is central to its function in protecting cells from oxidative stress and associated tissue injury. Vitamin E may also influence cell signaling and gene expression by modulating kinase activity (e.g., protein kinase C) and transcription. Although supplementation can correct deficiency and may reduce the oxidative component of some chronic diseases, vitamin E is a nutrient and antioxidant, not a therapeutic target molecule such as a receptor or enzyme.

Other names

Vitamin Ealpha-tocopheroltocopherolstocotrienols

Radical scavenging (terminates lipid peroxidation by donating hydrogen atoms to lipid radicals) Stabilizing cell membranes by preventing the accumulation of oxidized polyunsaturated fatty acids Recycled back to active form via ascorbate (vitamin C) or glutathione