Determining the hepati̇c effects of low dose zinc oxide nanoparticules

Zinc oxide nanoparticle (ZnO NP) is a widely used nanoparticle. Its main uses include food, cosmetics and health. Problems that cannot be solved with the use of macromolecules in the field of health have become possible with the use of nanoparticles due to their small size. However, it is known that zinc oxide nanoparticle can accumulate in the cell and cause toxic effects. Studies have shown the effects of high-dose zinc oxide nanoparticle exposure. There are not enough studies showing the low-dose effects of zinc oxide nanoparticle. In this study, zinc oxide nanoparticle (<100 nm) was administered to Sprague Dawley rats by intraperitoneal injection (i.p) for 28 days to create zinc oxide nanoparticle toxicity and the changes in the liver were investigated. Group I (Control: 0.9% NaCl); Group II (0,25 mg/kg/day ZnO NP); Group III (0,5 mg/kg/day ZnO NP); Group IV (1 mg/kg/day ZnO NP); Group V (2,5 mg/kg/day ZnO NP); Group VI (5 mg/kg/day ZnO NP); It was studied on 6 groups (n=8). Superoxide dismutase, catalase, total glutathione and malondialdehyde were measured biochemically. DNA damage was measured by Single Cell Gel Electrophoresis and histological changes in the liver tissue were examined with a light microscope. As a result of the biochemical analyzes performed, superoxide dismutase and catalase activities increased in all experimental groups compared to the control. A decrease was observed in the measured total glutathione levels in the experimental groups compared to the control group. It was observed that lipid peroxidation increased significantly starting from 1mg/kg/day (approximately 28%) and parallel to the dose increase (approximately 35% and 41%, respectively). In addition, necrotic areas in the liver where the histological structure was irreversibly damaged were observed at doses of 1 mg/kg/day and above. DNA damage, on the other hand, increased significantly in parallel with the dose increase starting from vi 0,5 mg/kg/day (approximately 2, 3, 4 and 6 times, respectively). However, the increase in DNA damage for 0,5 mg/kg/dose is thought to be reversible by DNA repair mechanisms. For low-dose zinc oxide nanoparticle, the lowest dose at which liver toxicity begins to appear was determined as 1 mg/kg/day. The toxicity observed at doses of 1 mg/day/kg and above was dose-dependent. In the light of the findings of this thesis, it was revealed that the doses that can be used safely with tolerable effects for zinc oxide nanoparticles are doses below 1mg/kg/day. It is thought that the findings of this study will make an important contribution to the literature for future studies on treatments that can be applied using zinc oxide nanoparticles and preparations that can be designed for various purposes.