Effects of copper oxide nanoparticles on the tissue and metabolic enzymes of liver and kidney of common carp (Cyprinus carpio)

Nowadays one of the aquatic environment problems is the entry of industrial wastewater containing nanoparticles. In the present study, the effects of copper oxide nanoparticles (CuO NPs) on some enzymes and histological alterations of liver and kidney tissues in the juvenile carp was assessed. At first, acute toxicity (LC50 96h) of CuO NPs were determined. Then, juvenile carps were exposed to the sublethal concentrations of 50, 100 and 200 mg/l of CuO NPs for 96h. Liver and kidney tissues of carp were separated after four periods. Also, ALT, AST, ALP and LDH enzyme activity assay in tissue extracts was done. The analysis of all enzymes activity in liver at a concentration of 200 mg/l after 96h, showed significant increase compared to the control treatment (P<0/05). In kidney, ALP and LDH enzyme activity for all of the four periods at concentration of 200 mg/l and GOT and GPT enzyme activity after 48, 72 and 96h at concentration of 100 and 200 mg/l showed significant difference. In the acute treatments of liver tissue side effects such as blood congestion, cellular necrosis, and cell atrophy and fatty degeneration was observed. kidney tissue were indicated same histopathological changes and shrinkage or degeneration of Bowman's capsule, glomerular expansion, hemosiderin deposits, tubular necrosis and degeneration or occlusion of the tubular lumen. The results showed that sublethal amounts of CuO NPs could affect the activity of the liver and kidney enzymes of the common carp and showed significant histopathological effects.