Screening tests of free radical scavengers for preventing sun-accelerated cutaneous ageing.

Synopsis Free radical formation has been shown to occur in UV-irradiated skin and a large body of evidence suggests that these reactive agents are responsible for sun-accelerated cutaneous ageing. The paper describes two tests for screening free radical scavengers potentially capable of inhibiting photo-induced skin alterations. They are based on analysis of thiobarbituric acid-reactive materials either in an acellular model in vitro or in the epidermis of rose bengal-sensitized mice after white light irradiation. The tests were illustrated with silymarin, a potent vegetable free radical scavenger.