title: Interaction of iron nanoparticles with nervous system: an in vitro study.
abstract: Nanoparticles (NPs) are one of the interesting and widely studying issues mainly because of their particular physico-chemical features and broad applications in the field of biomedical sciences, such as diagnosis and drug delivery. In this study, the interaction of iron nanoparticles (Fe-NPs) with Tau protein and PC12 cell, as potential nervous system models, was investigated with a range of techniques including dynamic light scattering, intrinsic fluorescence spectroscopy, circular dichroism, [(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium-bromid] assay, and acridine orange/ethidium bromide (AO/EB) dual staining method. An inverse correlation between Stern and Volmer constant (KSV) and temperature indicated a probable static quenching mechanism occurred between Tau protein and Fe-NPs. The number of binding site (n = 0.86) showed that there is almost one binding site of Fe-NP per protein. The negative values of ∆H (-53.21 kJ/mol) and T∆S (-42.44 kJ/mol) revealed that Fe-NPs interacts with Tau protein with dominate role of hydrogen bonds and van der Waals interactions and this interaction was spontaneous (∆G = -10.77 kJ/mol). Also, Fe-NPs stabilized the random coil structure of Tau protein. Moreover, Fe-NPs reduced PC12 cells viability by fragmentation of DNA in an apoptotic manner. In conclusion, induced conformational changes of Tau protein and cytotoxicity of PC12 cells by Fe-NP were revealed to be in a concentration and time-dependent manner.
authors.affiliation: a Department of Cell and Molecular Biology, Faculty of Advance Science and Technology, Pharmaceutical Sciences Branch , Islamic Azad University (IAUPS) , Tehran , Iran.
authors.forename: Gelare
authors.initials: G
authors.lastname: Hajsalimi
authors.affiliation: b Young Researchers and Elite Club, Islamshahr Branch , Islamic Azad University , Islamshahr , Iran.
authors.forename: Saba
authors.initials: S
authors.lastname: Taheri
authors.affiliation: c Young Researchers and Elite Club, Tehran Medical Sciences Branch , Islamic Azad University , Tehran , Iran.
authors.forename: Farshad
authors.initials: F
authors.lastname: Shahi
authors.affiliation: d Department of Biology, Faculty of Food Industry & Agriculture , Standard Research Institute (SRI) , Karaj , Iran.
authors.forename: Farnoosh
authors.initials: F
authors.lastname: Attar
authors.affiliation: e Department of Medical Biotechnology , National Institute of Genetic Engineering and Biotechnology (NIGEB) , Tehran , Iran.
authors.forename: Hosein
authors.initials: H
authors.lastname: Ahmadi
authors.affiliation: f Department of Nanotechnology, Faculty of Advance Science and Technology, Pharmaceutical Sciences Branch , Islamic Azad University (IAUPS) , Tehran , Iran.
authors.forename: Mojtaba
authors.initials: M
authors.lastname: Falahati
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002942:Circular Dichroism; D004247:DNA / Q000187:drug effects; D000067493:Dynamic Light Scattering; D006860:Hydrogen Bonding / Q000187:drug effects; D007501:Iron / Q000737:chemistry / Q000494:pharmacology*; D053768:Metal Nanoparticles / Q000737:chemistry*; D062105:Molecular Docking Simulation; D009420:Nervous System / Q000187:drug effects; D016716:PC12 Cells; D011487:Protein Conformation / Q000187:drug effects*; D051381:Rats; D013816:Thermodynamics; D016875:tau Proteins / Q000737:chemistry* / Q000235:genetics
chemical_list: D016875:tau Proteins; D004247:DNA; D007501:Iron
keywords: Tau protein; cell viability; interaction; iron nanoparticle; thermodynamic