The induction of apoptosis and reactive oxygen species in human skin fibroblast by ultraviolet A

To analyse the induction of apoptosis and reactive oxygen species (ROS) in human skin fibroblast by ultraviolet A (UVA).Human skin fibroblasts were irradiated with UVA, apoptosis was determined with flowcytometry and fluorescent microscopy, the intracellular ROS production was measured with a spectrofluorometer, and the free radicals were determined with electron spin resonance.A significant increase of apoptosis was observed in human skin fibroblast after exposure to UVA with a dosage at 110-120 kJ.m-2, mannitol could counteract apoptosis; a higher level of intracellular ROS and the hydroxyl free radical was detected in the irradiated samples.A lower dose of irradiation of UVA(0.6 mW.cm-2) can induce apoptosis in human skin fibroblast, and ROS might play a role in the induction of apoptosis.PubMed0169-733