title: Role of antioxidants in prevention of pyrimidine dimer formation in UVB irradiated human HaCaT keratinocytes.
abstract: The objective of the present study was to study the role of reactive oxygen species (ROS) in UVB induced cyclobutane pyrimidine dimer (CPD) formation in human keratinocytes, and to examine the modulating activity of low molecular weight antioxidants. To demonstrate the involvement of ROS, we examined the protective capacity of alpha-tocopherol, tempamine, and diethyldithiocarbamate (DDC) on CPD formation in intact cells and naked DNA. HaCaT cells and naked DNA in water solution were irradiated with UVB in the presence of the antioxidants and CPD was determined by ELISA. We found that all three antioxidants provided protection against UVB induced CPD formation. The protection was observed in intact cells only and not in naked DNA. Since some of the tested antioxidants do not possess UV absorbing qualities, our findings suggest that in a cellular environment ROS play a role in CPD formation.
authors.affiliation: Department of Dermatology, Hadassah Medical Center, Hebrew University, Jerusalem, Israel.
authors.forename: Malka
authors.initials: M
authors.lastname: Hochberg
authors.forename: Ron
authors.initials: R
authors.lastname: Kohen
authors.forename: Claes D
authors.initials: CD
authors.lastname: Enk
mesh_terms: D000975:Antioxidants / Q000494:pharmacology / Q000627:therapeutic use*; D002460:Cell Line; D004247:DNA / Q000096:biosynthesis / Q000302:isolation & purification; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects*; D015227:Lipid Peroxidation / Q000187:drug effects; D016877:Oxidants / Q000494:pharmacology; D011740:Pyrimidine Dimers / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D014466:Ultraviolet Rays; D014810:Vitamin E / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D016877:Oxidants; D011740:Pyrimidine Dimers; D017382:Reactive Oxygen Species; D014810:Vitamin E; D004247:DNA