Nakonechna, OksanaGubina-Vakulick, GalinaMiasoiedov, ValeriyGorbach, TatyanaDenysenko, SvitlanaYefimova, SvitlanaKlochkov, VladimirStetsenko, SvitlanaVasylyeva, IrinaYankovska, Daria2026-06-052026-06-052026-03European Journal of Clinical and Experimental Medicine T. 24, z. 1 (2026), s. 83–952544-1361https://repozytorium.ur.edu.pl/handle/item/12509The study protocol was approved by the Ethics Committee of Kharkiv National Medical University (protocol No. 5; 09.17.2019).Introduction and aim. Gadolinium–yttrium orthovanadate GdYVO4:Eu3+ nanoparticles (NPs) display dual redox activity, acting as pro-oxidants or antioxidants depending on the surrounding environment, concentration, and pretreatment conditions, a property that can be harnessed for potential oncological therapies. This study aims to evaluate the effect of untreated and UV-irradiated NPs administered orally on blood biochemical parameters, liver tissue, and histological condition of liver tissue in an experiment on laboratory rats. Material and methods. Male rats of the WAG population received oral colloidal NPs solutions (in untreated and UV-irradiated forms) at different doses: (50, 100, 200) μg/kg of body weight for 14 days. The content of medium-weight molecules, alanine aminotransferase activity, direct and indirect bilirubin content, and von Willebrand factor content were determined in blood serum. The content of reduced glutathione, superoxide dismutase, diene conjugates, and TBK-active products was determined in liver homogenates. Liver tissue samples were examined using morphological and morphometric methods. Results. The formation of oxidative stress, intoxication, damage to endothelial cells, impaired membrane permeability, destruction of hepatocytes, and destruction of sinusoidal endothelial cells were detected. Conclusion. It has been established that the introduction of GdYVO4: Eu3+ NP, both in untreated and UV-irradiated forms, induces dose-dependent effects, including oxidative stress, endothelial dysfunction, intoxication, damage to hepatocyte membranes, functional and histological damage to the liver, with more pronounced effects observed for UV-irradiated NPs.engAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/gadolinium-yttrium orthovanadate nanoparticleshepatotoxicityoxidative stressUV-irradiationarticle10.15584/ejcem.2026.1.16