title: Interaction of amorphous silica nanoparticles with erythrocytes in vitro: role of oxidative stress.
abstract: OBJECTIVE
  The use of engineered nanomaterials in the form of nanoparticles (NP) for various biomedical applications, as well as in consumer products, has raised concerns about their safety for human health. These NP are intended to be administered directly into the circulation following intravenous injection, or they may reach the circulation following other routes of administration such as oral or inhalation, and interact with circulating cells such as erythrocytes. However, little is known about the interaction of amorphous SiNP with erythrocytes.
  
  
  METHODS
  We studied the interaction of amorphous silica nanoparticles (SiNP) at various concentrations (1, 5, 25 and 125 µg/ml) with mouse erythrocytes in vitro.
  
  
  RESULTS
  Incubation of erythrocytes with SiNP caused a dose-dependent hemolytic effect. Likewise, the activity of lactate dehydrogenase was dose-dependently increased by SiNP. Transmission electron microscopy analysis revealed that SiNP are taken up by erythrocytes. Lipid erythrocyte susceptibility to in vitro peroxidation measured by malondialdehyde showed a significant and dose-dependent increase in erythrocytes. SiNP also enhanced the antioxidant activities of superoxide dismutase (SOD), catalase and reduced glutathione (GSH). Moreover, SiNP increased caspase 3, triggered annexin V-binding and caused a dose-dependent increase of cytosolic calcium concentration.
  
  
  CONCLUSIONS
  It can be concluded that SiNP cause a dose-dependent hemolytic activity and are taken up by the erythrocytes. We also found that SiNP induce the occurrence of oxidative activity, apoptosis and increase cytosolic Ca(2+), which may explain their haemolytic activity. Our in vitro data suggest that SiNP may, plausibly, lead to anemia and circulatory disorders in vivo.
authors.affiliation: Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
authors.forename: Abderrahim
authors.initials: A
authors.lastname: Nemmar
authors.forename: Sumay
authors.initials: S
authors.lastname: Beegam
authors.forename: Priya
authors.initials: P
authors.lastname: Yuvaraju
authors.forename: Javed
authors.initials: J
authors.lastname: Yasin
authors.forename: Allen
authors.initials: A
authors.lastname: Shahin
authors.forename: Badreldin H
authors.initials: BH
authors.lastname: Ali
mesh_terms: D000818:Animals; D017304:Annexin A5 / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D053148:Caspase 3 / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D004912:Erythrocytes / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D005978:Glutathione / Q000378:metabolism; D066298:In Vitro Techniques; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008315:Malondialdehyde / Q000378:metabolism; D051379:Mice; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles; D018384:Oxidative Stress; D012822:Silicon Dioxide / Q000737:chemistry*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D017304:Annexin A5; D008315:Malondialdehyde; D012822:Silicon Dioxide; D007770:L-Lactate Dehydrogenase; D002374:Catalase; D013482:Superoxide Dismutase; D053148:Caspase 3; D005978:Glutathione; D002118:Calcium