Size-Dependent Differences in the Effects of Low-Dose Selenium Nanoparticles on Chronic Thioacetamide Toxicosis Accompanying HCC Progression in Mice.

In recent decades, selenium nanoparticles have attracted increasing attention as therapeutic agents for the treatment of various types of cancer. However, at certain physicochemical parameters and dosages, they can have a toxic effect or exacerbate pathological processes caused by the toxin. The aim of this study was to investigate the effect of low doses of spherical selenium nanoparticles of two sizes (50 and 100 nm), produced by laser ablation, on the mitigation of pathological processes caused by long-term injections of thioacetamide. The practical significance of this study is to understand the therapeutic value of taking dietary supplements based on selenium nanoparticles for the prevention of various liver pathologies, particularly hepatocellular carcinoma. To this end, we selected the well-known toxin thioacetamide as an HCC inducer. We administered it intraperitoneally to animals, followed by injections of 50-100 nm selenium nanoparticles. In this study, we used ultra-low concentrations of selenium nanoparticles (1 ng/g per day) with the aim of using these nanoparticles for the prevention of fibrosis, cirrhosis, and liver cancer. The results obtained in this study demonstrate a size-dependent divergence in the biological behavior of the nanoparticles: 50 nm nanoparticles failed to inhibit tumor growth and, on the contrary, exacerbated pathological processes in the liver, kidneys, and lungs across several parameters, while 100 nm selenium nanoparticles, conversely, demonstrated a powerful therapeutic effect. This paradox is confirmed at all levels: organ, tissue, and cellular. The molecular mechanisms regulating these processes using 50 and 100 nm selenium nanoparticles are also presented.