title: Oxidative stress and in vivo chemiluminescence in mouse skin exposed to UVA radiation.
abstract: Mouse skin was exposed to UVA radiation (320-400 nm). The in vivo chemiluminescence of the skin was measured after irradiation. Chemiluminescence showed a maximum 13-fold increase (control emission, 10 +/- 1 cps cm-2) after 45-60 min of exposure to UVA, with no further increase with 60 min additional exposure. Spectral analysis of the emitted chemiluminescence showed that the principal species emitted in the 400-500 nm range. Topical application with alpha-tocopherol (10% v/w) and beta-carotene (1 mM) greatly reduced the UVA-induced skin chemiluminescence. Thiobarbituric acid reactive substance (TBARS) levels were increased by 130% in skin homogenates after 2 h of exposure to UVA (control value, 77 +/- 14 nmol malonaldehyde equivalents (g tissue)-1). The activities of antioxidant enzymes in skin homogenates were decreased after 2 h of irradiation: the superoxide dismutase (SOD) activity (control value, 181 +/- 10 U SOD (g tissue)-1) was decreased by 40% and the catalase activity (control value, 1.34 +/- 0.14 pmol (g tissue)-1) was decreased by 45%. In vivo chemiluminescence appears to be a suitable method for following the kinetics of the oxidative stress processes and for testing the effect of topical application with antioxidant and photoprotective agents.
authors.affiliation: Cátedra de Fisicoquímica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Argentina.
authors.forename: P
authors.initials: P
authors.lastname: Evelson
authors.forename: C P
authors.initials: CP
authors.lastname: Ordóñez
authors.forename: S
authors.initials: S
authors.lastname: Llesuy
authors.forename: A
authors.initials: A
authors.lastname: Boveris
mesh_terms: D000287:Administration, Topical; D000818:Animals; D002374:Catalase / Q000378:metabolism; D005260:Female; D008163:Luminescent Measurements; D051379:Mice; D018384:Oxidative Stress; D012867:Skin / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects*; D013482:Superoxide Dismutase / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D014466:Ultraviolet Rays; D014810:Vitamin E / Q000008:administration & dosage / Q000494:pharmacology; D019207:beta Carotene / Q000008:administration & dosage / Q000494:pharmacology
chemical_list: D017392:Thiobarbituric Acid Reactive Substances; D019207:beta Carotene; D014810:Vitamin E; D002374:Catalase; D013482:Superoxide Dismutase