Roles of oxidative stress in photoaging and the pathogenesis of systemic sclerosis

Abstract

Human skin is exposed to high amount of solar ultraviolet (UV) radiation, as well as to other environmental oxidants. Photoaging refers to the effect of long-term UV exposure and sun damage superimposed on intrinsically aged skin. The clinical photoaging features are dyspigmentation, laxity, wrinkles, and cutaneous malignancies. Most conspicuous photoaging change in dermis, which is caused by elastin materials accumulation, is termed "solar elastosis". Reactive oxygen species are known to be generated by UV radiation, and play an important role of photoaging. Although the pathogenesis of systemic sclerosis (SSc) remains unknown, oxidative stress has been suggested to contribute to clinical manifestations associated with SSc, such as vascular damage including Raynaud's phenomenon. This review focuses on recent data including our data which have demonstrated the critical role of oxidative stress in photoaging and the pathogenesis of SSc.