Neurotoxic effect of triazophos on goldfish (Carassius auratus) and tissue specific antioxidant responses

• Strong oxidative stress was induced in triazophos-exposed goldfish.
• Triazophos exposure caused a tissue specific antioxidant response.
• Triazophos induced a neurotoxic effect in goldfish brain.
• Brain may be a critical target for triazophos-induced oxidative damage.

Due to the high chemical and photochemical stability, an organophosphorus pesticide triazophos might enter aquatic ecosystems and impose negative effect on aquatic organisms. In order to investigate short-term toxicity of triazophos on goldfish (Carassius auratus), antioxidant response in brain, spleen, kidney and liver was tested in this study. As a confirmation, the impact of triazophos on acetyl cholinesterase (AChE) activity was found a reduction in all studied tissues, especially in brain. In addition, 0.1 and 0.5 mg L−1 triazophos induced MDA level increased, while glutathione content (GSH), superoxide dismutase (SOD), catalase (CAT) and lactate dehydrogenase (LDH) activities decreased. Of note, more prominent oxidative stress was provoked in kidney and liver, but weaker in brain and spleen. These results revealed that triazophos could cause a generalized oxidative stress and tissue specific antioxidant response in goldfish. Furthermore, neuroendocrine-growth-related gene expression (growth hormone (GH), luteinizing hormone (LH) and peptide YY) in brain was also changed by exposed to triazophos during 4 and 7 d exposure periods. Linked with the above results, the present study pointed out that triazophos might induce a neurotoxic effect and oxidative damage in goldfish, and the goldfish brain should be a critical target for triazophos-induced damage.

Triazophos induced an increase of lipid hydroperoxides (MDA level) and reduction of glutathione content (GSH), superoxide dismutase (SOD), and catalase (CAT), where excessive reactive oxygen species (ROS) was produced and the balance between oxidant substance and antioxidant enzyme in goldfish tissues was broken. Linked with the neuroendocrine-growth-related gene expression in brain, triazophos also induced a neurotoxic effect.Figure optionsDownload as PowerPoint slide