[摘要]：The chemoprotective effect of hydroxytyrosol (FIT) against UVB-induced DNA damage was investigated in a human skin keratinocyte cell line, HaCaT. The comet assay was used to monitor DNA strand breaks. Intracellular reactive oxygen species (ROS) formation was measured by How cytometry using 2,7-dichlorofluorescein diacetate (DCFH-DA). The levels of oxidatively generated damage to DNA were estimated by immunocytochemistry analysis of 8-hydroxy-2'-deoxyguanosine (8-OHdG). The protein expression of p53 and NF-kappa B was estimated by western blotting. The results showed that FIT significantly reduced the DNA strand breaks caused by UVB. It was also found that HT reduced intracellular ROS formation and 8-OHdG level caused by UVB. Furthermore, HT attenuated the expression of p53 and NF-kappa B in a concentration-de pendent manner. These results strongly suggest that FIT has a significant protective ability against UVB-induced DNA damage and that oxidative stress plays an important part in it. Copyright (C) 2009 John Wiley & Sons, Ltd.
