title: In vitro method for prediction of the phototoxic potentials of fluoroquinolones.
abstract: The phototoxic potential of eight fluoroquinolones (norfloxacin, ofloxacin, enoxacin, ciprofloxacin, lomefloxacin, tosufloxacin, sparfloxacin and gatifloxacin) was evaluated by using three in vitro methods of cytotoxicity against mammalian cells, erythrocyte lysis and DNA strand breakage. All fluoroquinolones tested with the exception of gatifloxacin, an 8-methoxy quinolone, showed DNA strand breaking activities under UV-A irradiation. Their cytotoxicity against HeLa cells was also enhanced by UV-A irradiation. In particular, the phototoxic potential of sparfloxacin, enoxacin and lomefloxacin was high in both methods. Ofloxacin is very photocytotoxic against HeLa cells, while it has low potential to cause DNA strand breakage. Norfloxacin, ciprofloxacin and enoxacin were very photohemolytic, but sparfloxacin was not, indicating that the in vivo phototoxic potencies of fluoroquinolones might not be predictable by the photohemolysis study. Gatifloxacin, a non-phototoxic quinolone, showed no phototoxic potential in any of these three in vitro tests. These results suggest that determination of DNA strand breaking activity, combined with cytotoxicity against mammalian cells, is available to predict the phototoxic potential of fluoroquinolones without laboratory animals.
authors.affiliation: Central Research Laboratories, Kyorin Pharmaceutical Co., Ltd, 2399-1, Nogi-Mitarai, Shimotsuga-gun, 329-0114, Tochigi, Japan. fvbb0984@mb.infoweb.ne.jp
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Y
authors.initials: Y
authors.lastname: Tsurumaki
authors.forename: M
authors.initials: M
authors.lastname: Takei
authors.forename: M
authors.initials: M
authors.lastname: Hosaka
authors.forename: Y
authors.initials: Y
authors.lastname: Oomori
mesh_terms: D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D004249:DNA Damage / Q000187:drug effects* / Q000528:radiation effects; D017484:Dermatitis, Phototoxic / Q000209:etiology*; D004305:Dose-Response Relationship, Drug; D004912:Erythrocytes / Q000187:drug effects* / Q000528:radiation effects; D024841:Fluoroquinolones / Q000633:toxicity*; D006367:HeLa Cells / Q000187:drug effects* / Q000528:radiation effects; D006461:Hemolysis / Q000187:drug effects* / Q000528:radiation effects; D006801:Humans; D014466:Ultraviolet Rays
chemical_list: D024841:Fluoroquinolones