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Background and Objective: Copper oxide nanoparticles, in addition to useful applications, may have adverse effects on the organisms.This study was done to determine the effect of copper oxide nanoparticles on liver toxicity, enzymes changes and liver histological structure of rats.
Methods: In this experimental study, 40 Wistar male rats were randomly allocated into 4 groups. During 10 days, five times (one day interval), 3 groups of rats were received 10, 20 and 30 mg/kg of copper oxide nanoparticles with a diameter of less than 50 nm and purity of 99% and a surface of 80 m²/g intraperitoneally, respectively. One group was considered as the control group. Activity of Lactate dehydrogenase (LDH), Alkaline phosphatase (ALP), Aspartate transaminase (AST) and Alanine aminotransferase (ALT) enzymes were tested in two stages (one day and 15 days after treatment). Also, liver tissue sections were prepared and stained with hematoxylin-eosin.
Results: No significant alterations of AST enzyme activity were not seen between different groups in two stages. The activity of ALT, ALP, and LDH enzymes in the first stage showed a significant increase in all treatment groups compared to control and returned to normal after 15 days. Rat's weight changes were not statistically significant between different groups. Histological studies revealed multiple tissue injuries in dose-dependent in treatment groups which included mild and severe hyperemia, hepatocytes degeneration, hyperplasia and inflammation.
Conclusion: Injection of low doses of copper oxide nanoparticles, after 15 days, although changes in enzyme activity return to normal, but significant disturbances observes in the structure of the liver tissue.