Human skin is relatively a complex structure with adapted barrier to the environment. Administration of chemical agents to the skin surface has long been practiced, whether for healing or purely decorative or cosmetic purposes. The skin is a semi permeable membrane and these open new possibilities for local treatment of the skin. An interesting strategy to provide photoprotection to the skin would be to support or enhance the endogenous antioxidant systems such as tocopherol or tocotrienols. Tocotrienols are fat-soluble vitamins related to the family of tocopherols (Figure 1). Structurally, tocopherols and tocotrienols share some resemblance consisting of a common chromanol head and a side chain at the C-2 position. However, tocopherols and tocotrienols are distinguished by their side chains and are further separated into individual compounds assigned by the Greek letter prefixes (α, β, δ and γ) depending on the number and position of methyl substitution on the chromanol ring. Both tocopherol and tocotrienol are well recognized for their antioxidant effect (Kamal-Eldin and Appleqvist, 1996). Contrary to popular believe, tocotrienol was observed in vitro to possess a remarkably higher antioxidant activity against lipid peroxidation than tocopherol (Serbinova et al., 1991) in biological membranes. It was reported that a single suberythemogenic dose of solar simulated ultraviolet radiation (UV; 0.75 minimal erythema dose, MED), depleted human stratum corneum α-tocopherol by almost 50% and murine stratum corneum α-tocopherol by 85% (Thiele et al., 1998). Thus, topical application of vitamin E (tocopherols and tocotrienols) in high doses may offer an alternative way in providing the stratum corneum with antioxidants.

Main Research: Zafarizal Aldrin Azizul Hassan