Caffeine protects human skin fibroblasts from acute reactive oxygen species-induced necrosis

Oxidative damage by reactive oxygen species (ROS) plays a major role in aging and carcinogenesis. Little is known about either the effects of acute ROS in necrosis and inflammation of skin or the therapeutic agents for prevention and treatment. Previously, our laboratory identified caffeine as an inhibitor of hydrogen peroxide (H ₂O₂)-generated lipid peroxidation products in human skin fibroblasts. Here, we study effects of caffeine on acute ROS-mediated necrosis. Human skin fibroblasts were incubated with caffeine, followed by H₂O₂ challenge. Flow cytometry was used to analyze cell morphology, counts, apoptosis and necrosis, and ROS. We found that caffeine protects from H₂O₂ cell damage at lower (0.01 mM) and intermediate (0.1 mM) doses. The beneficial effects of caffeine appear to be mediated by a mechanism other than antioxidant function.