Oxidative stress as a mechanism for toxicity of 2,4-dichlorophenoxyacetic acid (2,4-D): Studies with goldfish gills
The effects of exposure to the widely used herbicide, 2,4- dichlorophenoxyacetic acid (2,4-D), at environmentally permitted (1 mg L -1), slightly toxic (10 mg L-1), and highly toxic (100 mg L-1) concentrations were analyzed in gills of goldfish, Carassius auratus, a popular fish model for ecotoxicological research. Fish were exposed to the pesticide in water for 96 h and an additional group of fish were treated by the highest 2,4-D concentration and then allowed to recover for further 96 h. Among markers of oxidative stress, goldfish exposure to 2,4-D did not affect carbonyl protein levels in the gills, but fish exposure to 100 mg L-1 of 2,4-D enhanced lipid peroxide concentrations (by 58 %) and oxidized glutathione levels (by 49 %), the latter also significantly increasing (by 33 %) oxidized/total glutathione ratio. Activities of three enzymes of antioxidant defence also increased under 2,4-D exposure: superoxide dismutase (by 29-35 %), catalase (by 41 %), and glutathione peroxidase (by 19-33 %). Activities of other antioxidant associated enzymes as well as other potential markers of stress (e.g. aminotransferase enzymes, acetylcholinesterase, lactate metabolism) showed little or no response in gills to 2,4-D exposure. However, virtually all affected parameters returned to control values during recovery period. A combination of selected indices of oxidative stress and antioxidant defence, measured in fish gills, may provide to be effective biomarkers to assess environmental hazards of 2,4-D to freshwater ecosystems.
|Keywords||Acetylcholinesterase, Alanine and aspartate aminotransferases, Antioxidant defence, Catalase, Lactate metabolism, Lipid peroxides, Superoxide dismutase|
Atamaniuk, T.M. (Tetiana M.), Kubrak, O.I. (Olga I.), Storey, K, & Lushchak, V.I. (Volodymyr I.). (2013). Oxidative stress as a mechanism for toxicity of 2,4-dichlorophenoxyacetic acid (2,4-D): Studies with goldfish gills. Ecotoxicology, 22(10), 1498–1508. doi:10.1007/s10646-013-1136-z