Advances in the Study of Cerium Oxide Nanoparticles: New Insights into Antiamyloidogenic Activity

Abstract

There seems to be general agreement that oxidative stress is involved in many pathological conditions including Parkinson’s, Alzheimer’s, and other neurodegenerative diseases, and overall aging. Cerium oxide nanoparticles, also known as nanoceria (CeO2–NPs), have shown promise as catalytic antioxidants, based on their ability to switch between Ce3+ and Ce4+ valence states. In the present work we have synthesized and characterized CeO2–NPs, examined the effect of CeO2–NPs on amyloidogenesis of insulin, and analyzed the impact of CeO2–NPs on oxidative stress and biocompatibility in vitro in three types of invasive cancer cells, and in vivo in the preclinical model of the chorioallantoic membrane (CAM) of quail embryos. The different experimental techniques revealed a high stability and homogeneity of the “naked” CeO2–NPs synthesized by precipitation from a reversal microemulsion. The CeO2–NPs were 5–6 nm in diameter (TEM) and monodispersed and have a ζ +46.9 mV ζ potential in Milli-Q water. We demonstrated for the first time that CeO2–NPs affect insulin fibrillation in a dose-dependent manner. The inhibiting, IC50, and disassembling, DC50, concentrations were calculated to be ∼100 ± 3.5 and ∼200 ± 5.5 μg/mL, respectively. Furthermore, CeO2–NPs demonstrated reliable biocompatibility and sufficient uptake by glioma and breast cancer cells. The presence of a high concentration of CeO2–NPs within the cells resulted only in local changes in metabolic activity and generation of oxidative stress at a low level. Moreover, high biocompatibility with CeO2–NPs was shown in vivo in the CAM.

Adsorption properties, the pH-sensitive release of 5-fluorouracil and cytotoxicity studies of mesoporous silica drug delivery matrix

“…The cancer cells became highly adaptive to intracellular oxidative stress and revealed the way how to rescue and survive [60,67]. Recently, it was shown that the nanoceria applied to the U87 MG cells locally increased the oxidative stress level in the perinuclear area without affection of the cell proliferation [68]. One can expect the same behavior in cells treated with SBA-1.…”

Development of multifunctional nanocomposites for controlled drug delivery and hyperthermia

“…The IC 50 (the concentration of CZs required to inhibit fibril formation by 50%) and DC 50 (the concentration of CZs required to disassemble preformed fibrils by 50%) values were determined from fitting the dose-dependent experimental data using the nonlinear least-squares analysis with the sigmoidal sigmoid 3/4 parameter equation as described recently 36,37 . www.nature.com/scientificreports/ Anti-amyloidogenic activity assessment: microscopy techniques.…”

External and Internal Stimuli-Responsive Metallic Nanotherapeutics for Enhanced Anticancer Therapy

“…Additionally, these nanoparticles are incorporated with a fluorite crystalline lattice structure, resulting in a higher reactive surface area to scavenge free radicals. Owing to a lower redox potential (=1.52 v), CeO 2 nanoparticles can shift between Ce 3+ and Ce 4+ , depending upon the experimental conditions, a key feature for using CeO 2 nanoparticles as an antioxidant carrier (Siposova et al, 2019 ). Furthermore, the redox property of CeO 2 nanoparticles has been widely utilized against ROS-based tissue damage.…”