Study On The Toxicological Effects And Mechanisms Of Silver Nanoparticles On Endothelial System

With the rapid development of nanoscience and nanotechnology, biologicaleffects of nanomaterials on environment and human health are attracting considerableand increasing concern of scientists and governmental agencies worldwide. Silvernanoparticles (AgNPs) have been widely used in industry, daily life，and healthcaredue to the excellent antimicrobial activity. With the increased exposure to AgNPs, itssafety to human beings has becamea serious social and science problems. In this study,we focused on the potential nanotoxicity of AgNPs at a cell level and thetoxicological effects of AgNPs on endothelial system and the potential biologicalpathways. The main resluts are as follows:Firstly, we studied the toxicological effects of AgNPs on monocytes. We foundthat AgNPs induced lysosomal leakage, affected mitochondrial membrane potential,and induced ROS generation depending on stroreage time and AgNPs dose.Up-regulated apoptotic proteins: caspase-3, p53protein, Bax protein and affectanti-apoptotic Bcl-2protein expression. We thought that AgNPs induced cytotoxicityvia a mitochondrial apoptotic mechanism in THP-1cells.Secondly，we studied endothelial dysfunction and inflammation induced byAgNPs exposure and gove the risk factors for early atherosclerosis. The effects of AgNPs on cell viability, inlfammatory responses (MCP-1and ICAM-1)，and monocytesadhesion were comprehensively investigated by using different size-and dose-AgNPs. We found that adhesion of monocytes to the HUVECs was signiifcantlyenhanced as a consequence of the up-regulation of intracellular cell adhesionmolecule-1(ICAM-1), the activity of NF-kB is augmented during endothelialdysfunction and inflammation induced by AgNPs exposure.all of which areconsidered as early steps of atheroscelerosis.