title: Adaptive response of antioxidant enzymes to catalase inhibition by aminotriazole in goldfish liver and kidney.
abstract: This study was undertaken to clarify the physiological role of catalase in the maintenance of pro/antioxidant balance in goldfish tissues by inhibiting the enzyme in vivo with 3-amino 1,2,4-triazole. Intraperitoneal injection of aminotriazole (0.5 mg/g wet mass) caused a decrease in liver catalase activity by 83% after 24 h that was sustained after 168 h post-injection. In kidney catalase activity was reduced by approximately 50% and 70% at the two time points, respectively. Levels of protein carbonyls were unchanged in liver but rose by 2-fold in kidney after 168 h. Levels of thiobarbituric acid-reactive substances were elevated in both tissues after 24 h but were reversed by 168 h. Glutathione peroxidase and glutathione-S-transferase activities increased in kidney after aminotriazole treatment whereas activities of glutathione peroxidase and glutathione reductase in liver decreased after 24 h but rebounded by 168 h. Liver glucose-6-phosphate dehydrogenase activity was reduced at both time points. Activities of these three enzymes in liver correlated inversely with the levels of lipid damage products (R2=0.65-0.81) suggesting that they may have been oxidatively inactivated. Glutathione-S-transferase activity also correlated inversely with catalase (R2=0.86). Hence, the response to catalase depletion involves compensatory changes in the activities of enzymes of glutathione metabolism.
authors.affiliation: Department of Biochemistry, Precarpathian National University named after Vassyl Stefanyk, 57 Shevchenko Str., 76025, Ivano-Frankivsk, Ukraine.
authors.forename: Tetyana V
authors.initials: TV
authors.lastname: Bagnyukova
authors.forename: Kenneth B
authors.initials: KB
authors.lastname: Storey
authors.forename: Volodymyr I
authors.initials: VI
authors.lastname: Lushchak
mesh_terms: D000222:Adaptation, Physiological; D000640:Amitrole / Q000378:metabolism*; D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D002374:Catalase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000378:metabolism*; D006054:Goldfish; D007668:Kidney / Q000201:enzymology* / Q000378:metabolism; D008099:Liver / Q000201:enzymology* / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000975:Antioxidants; D004791:Enzyme Inhibitors; D017382:Reactive Oxygen Species; D002374:Catalase; D010100:Oxygen; D000640:Amitrole