title: Inhibitory effect of ascorbic acid post-treatment on radiation-induced chromosomal damage in human lymphocytes in vitro.
abstract: In the present study, the effect of exposure to ascorbic acid (vitamin C) after gamma-ray-induced chromosomal damage in cultured human lymphocytes was examined to explore the mechanism by which this antioxidant vitamin protects irradiated cells Non-irradiated lymphocytes were exposed to increasing concentrations of ascorbic acid (1-100 micro g/ml) and DNA damage was estimated using chromosomal aberration analysis and the comet assay. The results showed that ascorbic acid did not influence the frequency of chromosomal aberrations in non-irradiated cells, except at the highest concentration (20 micro g/ml), which induced breakage-type chromosomal aberrations. Vitamin C at the concentration of 50 micro g/ml caused DNA damage detected by the comet assay. A significant (34%) decrease in the frequency of chromosomal aberrations was observed in lymphocytes exposed to gamma-radiation and then cultured in the presence of ascorbic acid (1 micro g/ml). The removal of DNA breaks in cells exposed to 2 Gy of gamma-radiation was accelerated in the presence of ascorbic acid as determined by the comet assay, suggesting that it may stimulate DNA repair processes.
authors.affiliation: Department of Experimental and Clinical Radiobiology, Institute of Oncology, Gliwice, Poland. m_konopacka@pf.pl
authors.forename: Maria
authors.initials: M
authors.lastname: Konopacka
authors.forename: Olena
authors.initials: O
authors.lastname: Palyvoda
authors.forename: Joanna
authors.initials: J
authors.lastname: Rzeszowska-Wolny
mesh_terms: D000975:Antioxidants / Q000494:pharmacology; D001205:Ascorbic Acid / Q000494:pharmacology*; D002869:Chromosome Aberrations; D002875:Chromosomes / Q000528:radiation effects*; D020552:Comet Assay; D004249:DNA Damage; D004260:DNA Repair; D004305:Dose-Response Relationship, Drug; D005720:Gamma Rays; D006801:Humans; D066298:In Vitro Techniques; D008214:Lymphocytes / Q000528:radiation effects*
chemical_list: D000975:Antioxidants; D001205:Ascorbic Acid