title: Effects of UVA and visible light on the photogenotoxicity of benzo[a]pyrene and pyrene.
abstract: This study investigated the role of UVA/visible light (U, 320-800 nm) and visible light (V, 400-800 nm) in the phototoxicity and photogenotoxicity of two ubiquitous polycyclic aromatic hydrocarbons (PAH): benzo[a]pyrene (BaP) and Pyrene (Pyr). These mechanisms were evaluated by the WST-1 test and the comet assay on normal human keratinocytes (NHK) and by the micronucleus test on CHO cells. The production of reactive oxygen species (ROS) was assessed through the induction of 8-oxodeoxyguanine (8-oxodG) lesions by immunofluorescence staining in NHK. Results of the WST-1 test revealed the phototoxic properties of BaP and Pyr after irradiation with U and V lights. BaP presented the highest phototoxic properties. Results of the comet assay showed that U- and V-irradiated BaP and Pyr induced increasing rates of DNA single-strand breaks in NHK, in a dose dependent manner. The tested PAH could also induce increased levels of micronuclei in CHO cells after U and V irradiations. Increasing 8-oxodG levels were detected after U and V irradiations in BaP- and Pyr-treated keratinocytes and confirmed the involvement of ROS in the photogenotoxicity of PAH. Overall, this study highlighted the existence of an alternative pathway of PAH genotoxicity that is induced by UVA and/or visible light. Visible light is suggested to photoactivate PAH by a mechanism which is mainly based on oxidative reactions.
authors.affiliation: Laboratoire de Biogénotoxicologie et Mutagenèse Environnementale (EA 1784, FR 3098 - ECCOREV), Faculté de Pharmacie, Aix-Marseille Université, 27 Bd Jean Moulin, 13385 Marseille Cedex 05, France.
authors.forename: Céline
authors.initials: C
authors.lastname: Botta
authors.forename: Carole
authors.initials: C
authors.lastname: Di Giorgio
authors.forename: Anne-Sophie
authors.initials: AS
authors.lastname: Sabatier
authors.forename: Michel
authors.initials: M
authors.lastname: De Méo
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000818:Animals; D001564:Benzo(a)pyrene / Q000528:radiation effects / Q000633:toxicity*; D016466:CHO Cells; D002460:Cell Line; D002478:Cells, Cultured; D006224:Cricetinae; D003412:Cricetulus; D004249:DNA Damage; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000378:metabolism; D004785:Environmental Pollutants / Q000633:toxicity*; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism; D008027:Light; D009153:Mutagens / Q000633:toxicity*; D011721:Pyrenes / Q000528:radiation effects / Q000633:toxicity*; D014466:Ultraviolet Rays
chemical_list: D004785:Environmental Pollutants; D009153:Mutagens; D011721:Pyrenes; D001564:Benzo(a)pyrene; D000080242:8-Hydroxy-2'-Deoxyguanosine; C030984:pyrene; D003849:Deoxyguanosine