title: Magnetite induces oxidative stress and apoptosis in lung epithelial cells.
abstract: There is an ongoing concern regarding the biocompatibility of nanoparticles with sizes less than 100 nm as compared to larger particles of the same nominal substance. In this study, we investigated the toxic properties of magnetite stabilized with polyacrylate sodium. The magnetite was characterized by X-ray powder diffraction analysis, and the mean particle diameter was calculated using the Scherrer formula and was found to be 9.3 nm. In this study, we treated lung epithelial cells with different concentrations of magnetite and investigated their effects on oxidative stress and cell proliferation. Our data showed an inhibition of cell proliferation in magnetite-treated cells with a significant dose-dependent activation and induction of reactive oxygen species. Also, we observed a depletion of antioxidants, glutathione, and superoxide dismutase, respectively, as compared with control cells. In addition, apoptotic-related protease/enzyme such as caspase-3 and -8 activities, were increased in a dose-dependent manner with corresponding increased levels of DNA fragmentation in magnetite-treated cells compared to than control cells. Together, the present study reveals that magnetite exposure induces oxidative stress and depletes antioxidant levels in the cells to stimulate apoptotic pathway for cell death.
authors.affiliation: Department of Chemistry, Center for Biotechnology & Biomedical Sciences, Norfolk State University, Norfolk, VA 23504, USA.
authors.forename: Vani
authors.initials: V
authors.lastname: Ramesh
authors.forename: Prabakaran
authors.initials: P
authors.lastname: Ravichandran
authors.forename: Clinton L
authors.initials: CL
authors.lastname: Copeland
authors.forename: Ramya
authors.initials: R
authors.lastname: Gopikrishnan
authors.forename: Santhoshkumar
authors.initials: S
authors.lastname: Biradar
authors.forename: Virupaxi
authors.initials: V
authors.lastname: Goornavar
authors.forename: Govindarajan T
authors.initials: GT
authors.lastname: Ramesh
authors.forename: Joseph C
authors.initials: JC
authors.lastname: Hall
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D053181:Caspase 8 / Q000378:metabolism; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D005978:Glutathione / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008168:Lung / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D058185:Magnetite Nanoparticles / Q000633:toxicity*; D018384:Oxidative Stress / Q000187:drug effects*; D010316:Particle Size; D033362:Powder Diffraction; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D014961:X-Ray Diffraction
chemical_list: D058185:Magnetite Nanoparticles; D017382:Reactive Oxygen Species; D013482:Superoxide Dismutase; C505410:Casp3 protein, rat; C505528:Casp8 protein, rat; D053148:Caspase 3; D053181:Caspase 8; D005978:Glutathione