Protective Effects of Topical Vitamin C Compound Mixtures against Ozone-Induced Damage in Human Skin

Environmental pollution is a challenge to modern society, especially in developing countries. It has been estimated that more than 90% of the urban population live with pollutant levels in excess of World Health Organization standard limits (World Health Organization, 2016). There are numerous studies supporting the noxious effect that O3 exposure can have on cutaneous tissues; however, a drawback in the research has been a lack of data derived from humans. Recently, a retrospective study from Xu et al. (2011), collecting data from almost 70,000 patients, was able to correlate the rising incidence of emergency department visits for urticaria, eczema, and contact dermatitis to an increased ambient level of ozone (O3) (Xu et al., 2011). The evidence cited in current literature suggests the need to further investigate the harmful effect of O3 on human skin and to evaluate possible measures to counteract its effect. For this reason, the objective of this study was to investigate whether O3 exposure, at a level that has been observed in polluted cities (0.8 ppm), could affect skin tissue responses and whether vitamin C compound mixtures can prevent O3-induced skin damag

Ozone-induced damage in 3D-Skin Model is prevented by topical vitamin C and vitamin E compound mixtures application.

Because its critical location, the skin is the main target of environmental stressors such as ozone (O3). Although O3 does not penetrate the deeper layers of skin it is able to react readily with stratum corneum lipids [1]. The toxic effects of O3 on the uppermost layers, induced either directly by the oxidation of biomolecules or by driving the radical-dependent production of cytotoxic, non-radical species (aldehydes), have repercussions on deeper cellular layers, triggering a cascade of cellular stress and inflammatory responses that can lead to skin pathologies [2] and [3]. Furthermore, O3 is able to induce the depletion of cutaneous antioxidants [4]. Therefore, topical application of antioxidants could prevent pollution induces cutaneous damages. In our recent work, the use of topical antioxidant mixtures (MIXs) has proven an effective defensive approach against O3-induced oxidative damage in human keratinocytes [5]. In the present study, which is a methodological extension of the one recently published [5], we evaluated the ability of the three MIXs to prevent the noxious effects of O3 on a customized reconstructed human epidermis (RHE, Episkin), where sebum was applied to reproduce a model resembling “in vivo” expectations [