Magnetic γ-Fe2O3/CeOx nanoparticles were obtained by basic coprecipitation/oxidation of iron chlorides with hydrogen peroxide, followed by precipitation of Ce(NO3)3 with ammonia. The appearance of CeOx on the magnetic particle surface was confirmed by X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), and elemental analysis; a magnetometer was used to measure the magnetic properties of γ-Fe2O3/CeOx. The relatively high saturation magnetization of the particles (41.1 A·m2/kg) enabled magnetic separation. The surface of γ-Fe2O3/CeOx particles was functionalized with PEG-neridronate of two different molecular weights to ensure colloidal stability and biocompatibility. The ability of the particles to affect oxidative stress in hereditary hypertriglyceridemic (HHTg) rats was tested by biological assay of the liver, kidney cortex, and brain tissues. An improvement was observed in both enzymatic [superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx)] and non-enzymatic (reduced (GSH) and oxidized (GSSG) glutathione) levels of antioxidant defense and lipid peroxidation parameters [4-hydroxynonenal (4-HNE) and malondialdehyde (MDA)]. The results corresponded with chemical determination of antioxidant activity based on 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, proving that in the animal model γ-Fe2O3/CeOx@PEG2,000 nanoparticles effectively scavenged radicals due to the presence of cerium oxide, in turn decreasing oxidative stress. These particles may therefore have the potential to reduce disorders associated with oxidative stress and inflammation.

• Klíčová slova
• antioxidant, cerium oxide, maghemite, nanoparticles, oxidative stress,
• Publikační typ
• časopisecké články MeSH

Superparamagnetic iron oxide nanoparticles (SPIOn) are widely used as a contrast agent for cell labeling. Macrophages are the first line of defense of organisms in contact with nanoparticles after their administration. In this study we investigated the effect of silica-coated nanoparticles (γ-Fe2O3-SiO2) with or without modification by an ascorbic acid (γ-Fe2O3-SiO2-ASA), which is meant to act as an antioxidative agent on rat peritoneal macrophages. Both types of nanoparticles were phagocytosed by macrophages in large amounts as confirmed by transmission electron microscopy and Prusian blue staining, however they did not substantially affect the viability of exposed cells in monitored intervals. We further explored cytotoxic effects related to oxidative stress, which is frequently documented in cells exposed to nanoparticles. Our analysis of double strand breaks (DSBs) marker γH2AX showed an increased number of DSBs in cells treated with nanoparticles. Nanoparticle exposure further revealed only slight changes in the expression of genes involved in oxidative stress response. Lipid peroxidation, another marker of oxidative stress, was not significantly affirmed after nanoparticle exposure. Our data indicate that the effect of both types of nanoparticles on cell viability, or biomolecules such as DNA or lipids, was similar; however the presence of ascorbic acid, either bound to the nanoparticles or added to the cultivation medium, worsened the negative effect of nanoparticles in various tests performed. The attachment of ascorbic acid on the surface of nanoparticles did not have a protective effect against induced cytotoxicity, as expected.

• Klíčová slova
• Cytotoxicity, Macrophages, Nanoparticles, Oxidative stress,
• MeSH
• antioxidancia metabolismus   toxicita   MeSH
• krysa rodu Rattus MeSH
• kultivované buňky MeSH
• kyselina askorbová metabolismus   toxicita   MeSH
• magnetické nanočástice toxicita   MeSH
• peritoneální makrofágy účinky léků   metabolismus   MeSH
• potkani Wistar MeSH
• synergismus léků MeSH
• viabilita buněk účinky léků   fyziologie   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antioxidancia MeSH
• kyselina askorbová MeSH
• magnetické nanočástice MeSH