Article

Protection of normal human reconstructed epidermis from UV by catalase overexpression

INSERM E 0217, University Victor Segalen Bordeaux 2, 146 rue Léo Saignat, 33076 Bordeaux cedex, France.
Cancer Gene Therapy (Impact Factor: 2.55). 03/2007; 14(2):174-86. DOI: 10.1038/sj.cgt.7701000
Source: PubMed

ABSTRACT Reactive oxygen species (ROS) generated by ultraviolet (UV) irradiation are counterbalanced by endogenous antioxidant systems. To test the hypothesis of a novel photoprotective approach, we irradiated epidermis reconstructed with normal human keratinocytes overexpressing sustainably lentivirus-mediated catalase (CAT), copper/zinc superoxide dismutase (CuZnSOD) or manganese superoxide dismutase (MnSOD) enzymes. We found that following UVB irradiation there was a marked decrease in sunburn cell formation, caspase-3 activation and p53 accumulation in human reconstructed epidermis overexpressing CAT. Moreover, UVA-induced hypertrophy and DNA oxidation (8-oxodeoxyguanosine) were decreased by CAT overexpression. These effects were not achieved by overexpression of CuZnSOD or MnSOD. In conclusion, vector-mediated CAT overexpression could be a promising photoprotective tool against deleterious effects of UV irradiation such skin cancer especially in monogenic/polygenic photosensitive disorders characterized by ROS accumulation.

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