Oxidative stress responses in zebrafish Danio rerio after subchronic exposure to atrazine

Abstract

Atrazine is one of the most used pesticides all over the world and it is frequently detected in surface water. The aim of this study was to investigate if zebrafish exposure to atrazine could induce oxidative stress and changes in detoxifying system. Juvenile fish were exposed to sublethal concentrations of 0.3, 3, 30, or 90 μg L(-1) for 28 days. The level of oxidized lipids increased in experimental groups exposed to atrazine at 30 and 90 μg L(-1) compared to control. Activity of glutathione S-transferase decreased in group with the highest concentration compared to control. A significant decline was observed in catalase activity in all experimental groups compared to control. Activity of superoxide dismutase increased only in experimental group exposed to atrazine at 30 μg L(-1) compared to control. Activity of glutathione peroxidase and reductase (GR) increased in experimental groups exposed to atrazine at 0.3 (only for GR activity) and 90 μg L(-1) compared to control. Our results showed that atrazine exposure had profound influence on the oxidative stress markers and detoxifying enzyme of the exposed zebrafish. The changes in antioxidant enzyme activities could be an adaptive response to protect the fish from the atrazine-induced toxicity.

Keywords: CAT; Catalase; Fish; GPx; GR; GST; Glutathione dependent enzymes; Lipid peroxidation; NBT; ROS; SEM; SOD; Superoxide dismutase; TBARS; Triazine pesticides; catalase; glutathione S-transferase; glutathione peroxidase; glutathione reductase; nitroblue tetrazolium; r; reactive oxygen species; specific growth rate; standard error of mean; superoxide dismutase; thiobarbituric acid reactive substances.