Effects of waterborne copper on toxicity stress and apoptosis responses in red seabream, Pagrus major

Backgrounds: There has been an increasing trend of copper (Cu)-based aquaculture industry in the world, and it is necessary to evaluate the effect of copper ion exposure on water pollution. This study was aim to determine the critical concentration of toxic copper in adult red sea bream. Methods: Therefore, we investigated the effects of Cu toxicity on physiological stress and apoptosis exposed to various concentrations (10, 20, 30, and 40 mu g/L). We measured physiological stress-related (corticotrophin-releasing hormone, adrenocorticotropic hormone, cortisol, and glucose), other toxic stress-related (metallothionein and Na+/K+-ATPase), and apoptosis-related (caspase-3 and hydrogen peroxide) parameters. In addition, we confirmed apoptosis. Results: Physiological parameters were significantly increased from Cu concentration of 30 mu g/L or more. However, no significant differences were observed after exposures at 10 and 20 mu g/L. In addition, apoptotic cells were detected after exposure to 30 mu g/L. Conclusion: The results of this study indicate that high concentrations induce stress and apoptosis compared to normal conditions.