Oxidative Stress Mediates UVC-Induced Increases in Epidermal Autofluorescence of C57 Mouse Ears

Our recent study has reported that UV-induced epidermal autofluorescence (AF) can be used as a novel biomarker for predicting UV-induced skin damage, which is originated from UV-induced, cysteine protease-mediated keratin 1 degradation. A key question regarding these findings is: Does oxidative stress play a significant role in the UV-induced epidermal AF and keratin 1 proteolysis? In our current study, we administered the widely used antioxidant N-acetyl cysteine (NAC) into the skin of mouse ears to test our hypothesis that oxidative stress mediates UV-induced increases in the epidermal AF and keratin 1 degradation. Our study has shown that NAC administration can significantly attenuate the UVC-induced AF increases. The NAC administration can also significantly decrease the UVC-induced keratin 1 degradation. Collectively, our findings have indicated that the oxidative stress induced by UVC is causative to the UVC-induced increases in epidermal AF and keratin 1 proteolysis. Moreover, since oxidative stress is significantly increased in multiple regions of the body in several major diseases, the oxidative stress-induced increases in epidermal AF may become a novel biomarker for diagnosis of major diseases.