Nanopartículas híbridas de óxido de ferro e prata prejudicam o sistema colinérgico e causam reprotoxicidade em Caenorhabditis elegans

Abstract

Iron oxide nanoparticles (Fe3O4-NPs) exhibit superparamagnetic properties that enable their application in various areas, including drug delivery at specific locations in an organism. Silver nanoparticles (Ag-NPs) have potent antimicrobial effects. Although the combination of Fe3O4-NPs and Ag-NPs in one hybrid nanostructure (Fe3O4@Ag-NPs) demonstrated promising targeted biomedical applications, its toxicological effects are unknown and require further evaluation. We used Caenorhabditis elegans, an estabilished model for nanotoxicological analysis, because it allows for the initial screening of new substances. After acute exposure to Fe3O4-NPs, Ag-NPs, and Fe3O4@Ag-NPs, we observed that the hybrid NPs reduced C. elegans survival and reproduction. We also observed that Fe3O4@Ag-NPs caused an increase in germline cells apoptosis and a decrease in egg laying, which was associated with a decrease in worm swimming movements and abnormalities in cholinergic neurons. Fe3O4@Ag-NPs caused an increase in reactive oxygen species levels, along with the activation of the DAF-16 transcription factor. Higher expression of the target genes GST-4::GFP and SOD-3::GFP was observed, suggesting activation of the antioxidant system. Our results indicate reprotoxicity caused by high levels of Fe3O4@Ag-NPs, as well as cholinergic neurotoxicity and activation of the oxidant system in C. elegans, suggesting that high levels of these nanomaterials can be harmful to living organisms.