Correlation of biomarkers and histological responses in manufactured silver nanoparticle toxicity

Abstract

Today nanosciences are experiencing massive investment worldwide although research on toxicological aspect of these nano-sized particles has just begun and to date, no clear guidelines exist to quantify the effects. In the present study, we focus on silver nanoparticles, which represent one of the most widely investigated nanoparticles. The present data indicate that silver nanoparticles seem to cross the cellular membrane of various tissues in Sprague Dawley rat and, therefore, might have an influence on cell physiology and function. Rats are exposed via oral administration and intravenous injection with commercial silver nanoparticles. Three types of silver nanoparticels are used in this study: 1) Type I, particle size 50-90 nm with no dispersant, 2) Type II, particle size 1-10 nm dispersed with several amino acids. After 4 weeks exposure we examined the clinical indicators from blood and also analyzed histological changes in various tissues, including liver, kidney, and lung, to investigate the histopathological changes. The concentration of 2 indicators, total cholesterol and creatinine were changed with statistical importance. Also, lymphocytes/granulocyte ratio was significantly increased by silver nanoparticles. The histological change had accordance with the change of clinical indicators. The inflammatory symptoms were observed in liver tissue and it lead to the result that the hematologic/lymphocytic disorder, not hepatic disorder, would be related to silver nanoparticle toxicity. Finally we propose 4 genes as size independent genomic biomarkers and 10 genes as representative biomarkers for histopathological and clinical changes for silver nanoparticle exposure. © 2009 The Korean Society of Environmental Risk Assessment and Health Science and Springer.