Dynamics of the activity of hepato-specific enzymes and the state of protein synthesizer function of the liver in rats during chronic intake of zinc carbonate hydroxide nanoparticles

Toxicological properties of zinc-based nanoparticles (NPs) encourage researchers to create new, safe, and environmentally friendly compounds of this trace element. In this article, we determined the parameters of hepatotoxicity of zinc carbonate hydroxide (ZnCH) NPs obtained by coprecipitation method. For this purpose, in a chronic toxicological experiment on 25 male Wistar rats, the activity of liver indicator enzymes (ALT, AST, GGT, and ALP) and the protein profile of blood plasma were determined after administration of various doses of ZnCH NPs for 30 days. According to the results of studies on chronic oral administration of ZnCH NPs, there were no deaths or signs of intoxication in animals at the dose of 25–200 mg/kg body weight. Violations of the processes of natural detoxification of the body — a decrease in the activity of indicator enzymes in the liver of rats of experimental groups 1–3 were not observed. Only in experimental group 3 the GGT activity was higher on the 30th and 45th day — by 7.8 and 9.6%, respectively (P˂0.05) in comparison with the control group. In the animals of experimental group 4 (200 mg/kg body weight), ALT activity increased by 25.2% on day 30 of the study, and ALT and AST activity increased by 28.9% and 15.6%, respectively, on day 45 (P˂0.05). At the same time, animals in this group had significantly higher GGT activity throughout the study period: on days 15, 30, and 45 — by 8.8, 13.6, and 10.0%, respectively (P˂0.05–0.01). ALP activity showed similar dynamics: on days 15, 30, and 45, it was 25.1, 26.2, and 19.5% (P˂0.05) higher than the control values. The state of the protein-synthesizing function of the liver of rats after administration of ZnCH NPs in the dose of 25–100 mg/kg bw (experimental groups 1–3) did not undergo significant changes, but the trends observed during the experiment indicate an improvement of the protein profile, especially the level of globulins. In research group 4, a negative state of protein metabolism was noted ― the levels of total protein, albumins and globulins were lower than the control data throughout the study period