Comparing UV and Diesel Cutaneous Damage and Evaluating the Protective Role of a Topical Antioxidant Mixture Containing Vitamin C, E and Ferulic Acid

Cutaneous tissue is one of the main targets of outdoor stressors, and nowadays, the effect of pollution on skin conditions and premature skin ageing has been well correlated, although the exact effect that different pollutants have on the skin has not been well defined, especially when compared to other stressors. Among the air pollutants, UV radiation and particulate matter (PM) have been found among the most aggressive in terms of skin damage, inducing oxinflammatory responses, promoting degradation of extracellular matrix (ECM) components, and compromising the cutaneous defensive barrier. Topical application of technologies able to prevent oxidative damage is still one of the best approaches to protect our skin, and considering the well-known antioxidant network, application of an antioxidant mixture is more recommended than a single compound. In the present study, human skin explants were exposed every day for 4 days to diesel particles (DEE) or to UV after the daily pre-treatment with a topical application of a commercially available antioxidant mixture (AOX Mix), containing 15% ascorbic acid, 0.5% ferulic acid and 1% tocopherol. Oxidative stress markers such as 4-hydroxynonenal, skin barrier proteins such as involucrin, filaggrin, claudin-1 and desmocollin-1, resilience markers such as elastin and tropoelastin, and the levels of Type I and Type III collagens were assessed. Topical application was able to prevent most of the damage induced by the outdoor stressors, confirming that daily protection is needed to prevent cutaneous premature ageing.