The negative impacts of visible light, particularly blue light (wavelength 380-500nM), to skin are still not fully understood. A few studies have shown an increase of blue light-induced oxidative stress and hyperpigmentation suggesting a contribution to photo-aging (1–3). Only two UV-filters were found to partially block wavelength >380nm, hence additional means of protection are needed. We investigated blue light-induced cutaneous damages and screened for compounds to suppress these damages. Vitamins B3, B6 and E could prevent beta-carotene from blue light-dependent degradation in-vitro on PMMA plates. To investigate the potential of such compounds to suppress blue light induced damages in skin, we developed an ex-vivo model of blue light irradiation. Using fluencies of up to 100 Jcm-2 we could show a dose-dependent increase of reactive oxygen species, and we established protein carbonylation as a novel marker of blue light induced skin damage. We found that distinct compounds like vitamin B3 as well as an extract of the freshwater microalga Scenedesmus rubescens could suppress blue light induced damage significantly (p<0.05) ex-vivo.

Protection strategies to inhibit blue light irradiation effects in-vitro and in skin ex-vivo.