Ozone depletes tocopherols and tocotrienols topically applied to murine skin

To evaluate ozone damage to hairless mouse skin, two parameters of oxidative damage, vitamin E depletion and malondialdehyde (MDA) production, were measured in vitamin E-enriched and in control skin from mice exposed to ozone (10 ppm), A 5% vitamin E solution (tocotrienol-rich fraction, TRF) in polyethylene glycol (PEG) was applied to 2 sites on the back of hairless mice, PEG to 2 sites, After 2 h, the sites were mashed, one of each pair of sites covered and the mice exposed ozone for 2 h, Ozone exposure (compared with covered sites) increased epidermal MDA in PEG-treated sites, while vitamin E was unchanged, In contrast, ozone exposure significantly depleted vitamin E in TRF-treated sites, while significant MDA accumulation mas prevented, This is the first demonstration that ozone exposure causes damage to cutaneous lipids, an effect which can be attenuated by vitamin E application.