Toxicological Impacts on Antioxidant Responses, Stress Protein, and Genotoxicity Parameters of Aluminum Oxide Nanoparticles in the Liver of Oreochromis niloticus.

The aim of this study was to determine the toxic effects of aluminum oxide nanoparticles (Al2O3 NPs) on oxidative stress, stress protein, and genotoxicity parameters in Oreochromis niloticus. Ninety-six-hour LC50 value of Al2O3 NPs was found as 52.4 ppm for O. niloticus. The fish were exposed to 2.6 ppm (5% of the 96-h LC50) and 5.2 ppm (10% of the 96-h LC50) for 3 days and 7 days. Various biochemical parameters, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) activities, glutathione (GSH), thiobarbituric acid reactive substance (TBARS), heat shock protein 70 (HSP70; stress protein), and genotoxicity biomarker 8-hydroxy-2-deoxyguanosine (8-OHdG) levels, were determined. Results showed that antioxidant enzymes were significantly decreased in SOD, CAT, and GPx enzyme activity, but GST enzyme activity was significantly increased in 7 days. The oxidative stress parameters, GSH levels, were significantly decreased while 8-OHdG and TBARS levels were increased in 3 and 7 days. HSP70 levels were decreased in the concentrations of Al2O3 NPs and exposure times. Our results showed that as a result of changes in oxidative stress parameters, stress protein, and genotoxicity parameters, O. niloticus liver tissue is highly sensitive and toxic to aluminum oxide nanoparticle exposure.