UVB-induced apoptosis and DNA damaging potential of chrysene via reactive oxygen species in human keratinocytes.

Chrysene is one of the basic polycyclic aromatic hydrocarbon (PAH) which is toxic environmental pollutant and consistently exposed to sunlight. However, little information is available on its photogenotoxicity. The objective of the present study was to analyze the effects of chrysene, under environmental intensity of UVB (0.6mW/cm(2)) in human skin epidermal cell line (HaCaT). Kinetic of chrysene showed that the highest intracellular uptake of chrysene occurred after 24h of incubation. The intracellular reactive oxygen species (ROS) was increased in a concentration dependent manner in chrysene treated cells under UVB irradiation. It was observed that UVB-irradiated chrysene induced apoptosis through activation of caspases-3 and phosphatidylserine translocation. Glutathione reduced (GSH) and catalase activity were decreased while apoptosis and DNA damage were induced significantly (P>0.01) as concentration of chrysene increased. Thus our results suggest that chrysene may be phototoxic as well as photogenotoxic under UVB irradiation.