Comparative study of toxicological effect of iron oxide nanoparticles in human nerve cells

Abstract

Due to their unique physicochemical properties, iron oxide nanoparticles (ION) have great potential for several biomedical applications, particularly those focused on nervous system. ION surface can be coated to improve their properties and biocompatibility. Still, coating may affect toxicity, making it imperative knowing the potential risk associated to nervous system exposure. The aim of this Thesis was to assess the potential cytotoxicity and genotoxicity induced by differently coated ION on human neurons (SH-SY5Y) and astrocytes (A172), under a range of doses, two treatment times and presence/absence of serum in the cell culture media. Cellular uptake of ION and iron ion release from the ION surface were also determined. In general, silica-coated ION (S-ION) showed less cytotoxicity and slightly lower genotoxic effects than oleic acid-coated ION (O-ION), not related to double strand breaks (DSB) or chromosome alterations. Furthermore, A172 astrocytes proved to be more sensitive than SH-SY5Y neurons to the toxic effect of both ION. In addition, primary DNA damage observed in both cell types only included DSB in astrocytes. This work increases the knowledge on the impact of ION on human health in general, and specifically on nervous system cells