Protective effect of dl-alpha-tocopherol on the cytotoxicity of ultraviolet B against human skin fibroblasts in vitro.
The effect of dl-alpha-tocopherol on ultraviolet light, 280-320 nm (UVB)-induced damage of human skin fibroblasts was studied by measuring the colony-forming ability, unscheduled DNA synthesis (UDS) and malondialdehyde (MDA) production. Regarding the cell toxicity, the values of the mean lethal dose (D0) of UV in fibroblast strains from 5 normal subjects were examined. D0 increased dose-dependently when the cells were cultured in the presence of dl-alpha-tocopherol at the concentration of 10-1000 micrograms/ml. UDS induced by 500 J/m2 UVB irradiation was not altered by treatment of 100 micrograms/ml dl-alpha-tocopherol. MDA did not increase after 500 J/m2 UVB irradiation in the fibroblasts cultured with 100 micrograms/ml dl-alpha-tocopherol, while MDA in the fibroblasts cultured without dl-alpha-tocopherol increased after irradiation. These results suggest that dl-alpha-tocopherol protects human skin fibroblasts against the cytotoxic effect of UVB, and its mechanism seems to be related to inhibition of UV-induced lipid peroxidation or to the antioxidation effect of dl-alpha-tocopherol.
Kondo
S
S
Department of Dermatology, School of Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
Mamada
A
A
Yamaguchi
J
J
Fukuro
S
S
D000293:Adolescent; D000328:Adult; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism / Q000528:radiation effects; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008875:Middle Aged; D012867:Skin / Q000166:cytology; D014466:Ultraviolet Rays / Q000009:adverse effects*; D014810:Vitamin E / Q000494:pharmacology*
D014810:Vitamin E; D008315:Malondialdehyde; D004247:DNA