In-vivo effects of solar-simulated ultraviolet irradiation on antioxidant enzymes and lipid peroxidation in human epidermis.

The effects of solar-simulated UV-irradiation on the activity of antioxidant enzymes and the amount of diene conjugation were studied in human epidermis in vivo. A single dose of UV-irradiation was found to result in a transient reduction in superoxide dismutase activity and this was followed by increased amounts of conjugated diene double bonds, an index for oxidative stress. This suggests that in-vivo exposure of human epidermis to solar-simulated UV-irradiation causes changes in the enzymic antioxidant defence system which, in turn, are accompanied by increased level of oxidative stress.