title: Titanium-doped cerium oxide nanoparticles protect cells from hydrogen peroxide-induced apoptosis.
abstract: To develop new nanoparticle materials possessing anti-oxidative capacity with improved physical characteristics, we have studied titanium-doped cerium oxide (CeTiO2) nanoparticles. CeTiO2nanoparticles had a mode diameter of 15-20 nm. These nanoparticles demonstrated catalase activity, and did not promote the activation of hemolytic or cytolytic pathways in living cells. Using surface plasmon resonance enhanced microscopy, we find that these nanoparticles associate with cells. Transmission electron microscopy studies demonstrated that these nanoparticles accumulate within the vacuolar compartment of cells. Importantly, CeTiO2nanoparticles decrease hydrogen peroxide-mediated apoptosis of cells as judged by the reduced cleavage of a caspase 3-sensitive label. CeTiO2nanoparticles may contribute to deflecting tissue damage in a broad spectrum of oxidant-mediated diseases, such as macular degeneration and Alzheimer's disease.
authors.affiliation: Department of Ophthalmology and Visual Sciences, The University of Michigan Medical School, Ann Arbor, MI 48105.
authors.forename: Andrea
authors.initials: A
authors.lastname: Clark
authors.affiliation: Department of Ophthalmology and Visual Sciences, The University of Michigan Medical School, Ann Arbor, MI 48105.
authors.forename: Aiping
authors.initials: A
authors.lastname: Zhu
authors.affiliation: Department of Ophthalmology and Visual Sciences, The University of Michigan Medical School, Ann Arbor, MI 48105.
authors.forename: Howard R
authors.initials: HR
authors.lastname: Petty
keywords: Catalytic nanoparticles; apoptosis; cell toxicity; reactive oxygen metabolites