Comparative Evaluation of the Expression of Apoptosis Proteins at the Influence of Metal Containing Polymeric Nanocomposites on the Brain

Abstract

Background. The creation and the attempt to introduce into medicine new nanostructured materials dictate the need for careful study of their safety for human health and the environment. At the same time, the existing classical approaches to safety assessment do not always objectively reflect the real state of affairs; therefore, there is a need to introduce new approaches, including methods of intracellular safety assessment of nanoparticles and nanomaterials.The aim of this study was to evaluate expression level of apoptosis-regular proteins caspase-3 and bcl-2 in neurons of white outbred rats exposed to nanocomposites consisting of nanoparticles of metals (silver, bismuth and gadolinium) on a natural matrix of arabinogalactan isolated from Siberian larch wood.Materials and methods. Sixty outbred male rats were exposed to nanocomposites for 9 days at a dose of 500 μg of metal per 1 kg of animal body weight. The introduction of substances was carried out orally using atraumatic probe. Study of the activity of proteins of apoptosis modulators caspase-3 and bcl-2 and calculate the percentage of different types of reacted neurons was conducted. Statistics 6.1 was used to process results, p-values less than 0.01 were acknowledged as statistically significant.Results. It was found that the activation of apoptotic process occurs only when the nanocomposite is affected with the addition of silver nanoparticles, which are realized in a significant increase in the percentage of all types of neurons under study.Conclusion. Monitoring proteins – regulators of apoptosis can serve as a marker of early damage to nerve cells, since glial cells can form at the site of dead neurons that do not fulfill the main function of transmission of nerve impulses. The results obtained allow us to substantiate the need for a more thorough and prolonged study of silver nanoparticles encapsulated on the arabinogalactan matrix.