title: Nanoceria as bona fide catalytic antioxidants in medicine: what we know and what we want to know….
abstract: Cerium oxide (CeO2) nanoparticles, CeNPs or nanoceria are inorganic and possess catalytic antioxidant activity. They scavenge reactive oxygen species and act as an oxygen buffer. Their application in industry is well-established. However, their usage as bona fide antioxidants in biological systems has been recent and is quite revolutionary. Other reviews have documented nanoceria's protective effect in reducing oxidative stress in cell culture and in animal disease models that are associated with oxidative stress. We specifically have targeted CeNPs as ophthalmic therapeutics to slow the progression of retinal degeneration and as anti-angiogenic agents in rodent models. The radical scavenging activity of CeNPs is mainly due to the dramatic increase of surface area to volume ratio in these nanocrystalline structures. The parameters for CeNPs usage in industrial settings are decidedly not suitable for biological applications. In this short review, we report the pharmacokinetics, biodistribution, and toxicity evaluation of CeNPs when applied as ophthalmic therapeutic agents in an in vivo system. We highlight studies that examine how CeNPs behave in biological environments and how they interact with bio-macromolecules. We also discuss studies that examine the dynamic changes of the surface chemistry of CeNPs in physiological buffers. Finally, we raise a list of questions that we think ought to be answered for CeNPs to be considered the antioxidants of choice in medicine, specifically in the treatment of ocular diseases.
authors.affiliation: Department of Ophthalmology, College of Medicine, University of Oklahoma Health Sciences Center (OUHSC) and Dean McGee Eye Institute, 608 Stanton L Young Blvd, DMEI PB L027, 73104, Oklahoma City, OK, USA, lily-wong@ouhsc.edu.
authors.forename: Lily L
authors.initials: LL
authors.lastname: Wong
authors.forename: James F
authors.initials: JF
authors.lastname: McGinnis
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism* / Q000494:pharmacology; D002563:Cerium / Q000378:metabolism* / Q000494:pharmacology; D006801:Humans; D053758:Nanoparticles / Q000378:metabolism*; D012162:Retinal Degeneration / Q000188:drug therapy* / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D002563:Cerium; C030583:ceric oxide