title: Limited effectiveness of antioxidants in the protection of yeast defective in antioxidant proteins.
abstract: Efficacy of several antioxidants in the protection of the yeast Saccharomyces cerevisiae mutants deficient in CuZnSOD and deficient in glutaredoxin 5 to growth restriction induced by oxidants was studied. Ascorbate and glutathione protected the Deltasod1 and Deltagrx5 mutants against the effects of t-butyl hydroperoxide and cumene hydroperoxide, Deltasod1 mutants against oxytetracycline and Deltagrx5 mutants against menadione and 2,2'-azobis-(2-amidinopropane). However, Tempol, Trolox and melatonin were much less effective, showing prooxidative effects and, at high concentrations, hampering the growth of the mutants in the absence of exogenous oxidants. These results point to a complication of cellular effects of antioxidants by their prooxidative effects and to the usefulness of cellular tests to evaluate the biological effectiveness of antioxidants.
authors.affiliation: Department of Biochemistry and Cell Biology, University of Rzeszów, ul. Cegielniana 12, PL 35-595 Rzeszów, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Lewinska
authors.forename: Tomasz
authors.initials: T
authors.lastname: Bilinski
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Bartosz
mesh_terms: D000975:Antioxidants / Q000378:metabolism* / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology; D049109:Cell Proliferation / Q000187:drug effects; D054477:Glutaredoxins; D008550:Melatonin / Q000494:pharmacology; D009154:Mutation / Q000235:genetics; D016877:Oxidants / Q000494:pharmacology; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism; D000072105:Superoxide Dismutase-1
chemical_list: D000975:Antioxidants; D054477:Glutaredoxins; D016877:Oxidants; D029701:Saccharomyces cerevisiae Proteins; D010088:Oxidoreductases; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1; D008550:Melatonin; D001205:Ascorbic Acid