The effect of vitamin C on oxygen radical-induced sister-chromatid exchanges.
We studied the effects of vitamin C (sodium ascorbate) on the genotoxicity of oxygen radicals to tissue culture cells. Chinese hamster ovary cells (CHO cells), when exposed to an enzymatic oxygen radical generating system (xanthine oxidase plus hypoxanthine), develop increased numbers of sister-chromatid exchanges (SCEs). Inclusion of ascorbate in these incubations resulted in significant, but variable effects. In some cases, ascorbate (less than 0.1 mM) was protective and fewer SCEs were produced. In others, significant augmentation of oxygen radical-induced SCEs occurred. These experiments illustrate the complexity of the interactions of ascorbate in biologic systems and the difficulty of predicting a desirable or harmful effect.
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D001205:Ascorbic Acid / Q000494:pharmacology*; D002460:Cell Line; D006224:Cricetinae; D003412:Cricetulus; D004347:Drug Interactions; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000648:ultrastructure; D005609:Free Radicals; D006801:Humans; D019271:Hypoxanthine; D007042:Hypoxanthines / Q000494:pharmacology; D007962:Leukocytes / Q000187:drug effects / Q000648:ultrastructure; D010053:Ovary; D010084:Oxidation-Reduction; D010100:Oxygen / Q000494:pharmacology*; D012854:Sister Chromatid Exchange / Q000187:drug effects*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014969:Xanthine Oxidase / Q000378:metabolism
D000975:Antioxidants; D005609:Free Radicals; D007042:Hypoxanthines; D019271:Hypoxanthine; D014969:Xanthine Oxidase; D013755:Tetradecanoylphorbol Acetate; D001205:Ascorbic Acid; D010100:Oxygen