title: Cellular responses induced by cerium oxide nanoparticles: induction of intracellular calcium level and oxidative stress on culture cells.
abstract: Cerium oxide (CeO(2)) is an important metal oxide used for industrial products. Many investigations about the cellular influence of CeO(2) nanoparticles have been done, but results are contradictory. It has been reported that CeO(2) nanoparticles have an anti-oxidative effect in cells, but it has also been reported that CeO(2) nanoparticles induce oxidative stress. We investigated the potential influence on cells and the mechanisms induced by CeO(2) nanoparticles in vitro. We prepared a stable CeO(2) culture medium dispersion. Cellular responses in CeO(2) medium-exposed cells were examined. Cellular uptake of CeO(2) nanoparticles was observed. After 24-h exposure, a high concentration of CeO(2) nanoparticles (∼200 mg/ml) induced an increase in the intracellular level of reactive oxygen species (ROS); a low concentration of CeO(2) nanoparticles induced a decrease in the intracellular ROS level. On the other hand, exposure of CeO(2) nanoparticle for 24 h had little influence on the cell viability. Exposure of CeO(2) nanoparticles increased the intracellular Ca(2+) concentration and also Calpain was activated. These results suggest that CeO(2) nanoparticles have a potential to induce intracellular oxidative stress and increase the intracellular Ca(2+) level, but these influences are small.
authors.affiliation: Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31, Midorigaoka, Ikeda, Osaka 563-8577, Japan. masa-horie@med.uoeh-u.ac.jp
authors.forename: Masanori
authors.initials: M
authors.lastname: Horie
authors.forename: Keiko
authors.initials: K
authors.lastname: Nishio
authors.forename: Haruhisa
authors.initials: H
authors.lastname: Kato
authors.forename: Katsuhide
authors.initials: K
authors.lastname: Fujita
authors.forename: Shigehisa
authors.initials: S
authors.lastname: Endoh
authors.forename: Ayako
authors.initials: A
authors.lastname: Nakamura
authors.forename: Arisa
authors.initials: A
authors.lastname: Miyauchi
authors.forename: Shinichi
authors.initials: S
authors.lastname: Kinugasa
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Etsuo
authors.initials: E
authors.lastname: Niki
authors.forename: Yasukazu
authors.initials: Y
authors.lastname: Yoshida
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Hagihara
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Iwahashi
mesh_terms: D000327:Adsorption; D002118:Calcium / Q000378:metabolism*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002563:Cerium / Q000494:pharmacology*; D006801:Humans; D042541:Intracellular Space / Q000187:drug effects* / Q000378:metabolism; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D053758:Nanoparticles / Q000737:chemistry*; D018384:Oxidative Stress / Q000187:drug effects*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013329:Structure-Activity Relationship; D013499:Surface Properties
chemical_list: D017382:Reactive Oxygen Species; D002563:Cerium; C030583:ceric oxide; D002118:Calcium