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A high risk of complications in burn injuries is associated with the development of systemic inflammatory response syndrome. Thermal injury (burn) causes the release of cytokines and prostaglandia, resulting in increased interaction between leukocytes, platelets and endothelial cells. Activation of leukocytes leads to an increase in the formation of reactive oxygen species (ROS) and nitrogen, which is normally compensated by the activation of protective antioxidant enzymes. An imbalance between the activity of the radical-producing and antioxidant systems leads to an excess of free radicals and the development of oxidative stress. Oxidative stress limits the repair of damaged tissue and also leads to localized chronic inflammation. Thus, the removal of inflammation and a decrease in the ROS level, which exceeds the physiological level in the burn zone, seems to be expedient for accelerating the healing process of burn injuries of the skin. In this study, we used a polysaccharide hydrogel modified with cerium dioxide (CeO2) nanoparticles, which have unique anti-inflammatory and antioxidant properties, as an effective agent for the treatment of thermal burns. It has been shown that modification of the hydrogel with CeO2 nanoparticles provides accelerated healing of a model burn wound in rats. Already on the 5th day after the treatment of damage to the skin with the modified hydrogel, a decrease in the area of ​​the burn wound that is different from the control is observed. The use of a hydrogel accelerates the healing process of a burn wound on the 25th day by 25.42% (p 2 nanoparticles can be considered as an effective wound healing agent in the treatment of thermal burns and skin lesions of various etiologies.

Gd-based complexes are widely used as magnetic resonance imaging (MRI) contrast agents. The safety of previously approved contrast agents is questionable and is being re-assessed. The main causes of concern are possible gadolinium deposition in the brain and the development of systemic nephrogenic fibrosis after repeated use of MRI contrasts. Thus, there is an urgent need to develop a new generation of MRI contrasts that are safe and that have high selectivity in tissue accumulation with improved local contrast. Here, we report on a new type of theranostic MRI contrast, namely dextran stabilised, gadolinium doped cerium dioxide nanoparticles. These ultra-small (4–6 nm) Ce0.9Gd0.1O1.95 nanoparticles have been shown to possess excellent colloidal stability and high r1-relaxivity (3.6 mM−1 s−1). They are effectively internalised by human normal and cancer cells and demonstrate dose-dependent selective cytotoxicity to cancer cells.

A technique for the fabrication of bacterial cellulose-based films with CeO2 nanofiller has been developed. The structural and morphological characteristics of the materials have been studied, their thermal and mechanical properties in dry and swollen states having been determined. The preparation methodology makes it possible to obtain composites with a uniform distribution of nanoparticles. The catalytic effect of ceria, regarding the thermal oxidative destruction of cellulose, has been confirmed by TGA and DTA methods. An increase in CeO2 content led to an increase in the elastic modulus (a 1.27-fold increase caused by the introduction of 5 wt.% of the nanofiller into the polymer) and strength of the films. This effect is explained by the formation of additional links between polymer macro-chains via the nanoparticles’ surface. The materials fabricated were characterized by a limited ability to swell in water. Swelling caused a 20- to 30-fold reduction in the stiffness of the material, the mechanical properties of the films in a swollen state remaining germane to their practical use. The application of the composite films in cell engineering as substrates for the stem cells’ proliferation has been studied. The increase in CeO2 content in the films enhanced the proliferative activity of embryonic mouse stem cells. The cells cultured on the scaffold containing 5 wt.% of ceria demonstrated increased cell survival and migration activity. An analysis of gene expression confirmed improved cultivation conditions on CeO2-containing scaffolds.

The results of studies into microporous scaffolds based on polycaprolactone, in particular, involving nanoparticles and microparticles of modified (silicon-containing) hydroxyapatite (hybrid scaffolds) are presented. When hydroxyapatite particles are used during the electrospinning of polymer scaffolds, their porosity is found to increase substantially and a structure with nanofibers and microfibers can be created. X-ray phase analysis demonstrates that the characteristic lines of polycaprolactone and hydroxyapatite exist in the 3D hybrid scaffold structure. According to the data of infrared (IR) spectroscopy of the hydroxyapatitepowder precursor, (SiO4)4– ions are embedded in its lattice. The results of studies into the surface wettability indicate that the contact angles of wetting with water are smaller for hybrid scaffolds than for pure polycaprolactone scaffolds. Adhesive and proliferative activity tests of human mesenchymal stem cells (MSCs) performed upon hybrid-scaffold cultivation on the surface, as well as histologic investigations, indicate the high biocompatibility of the samples. On the basis of a polymerase chain reaction, it is revealed that the differentiation of MSCs occurs in the osteogenic direction. On account of a porous structure, hybrid scaffolds can be employed to recover bone-tissue defects.

Cerium oxide nanoparticles (nanoceria) are regarded as one of the most promising inorganic antioxidants for biomedical applications. Considering nanoceria as a potential therapeutic agent, we aimed to develop a robust system for its intracellular delivery using layer-by-layer polyelectrolyte microcapsules. We have shown that citrate-stabilized cerium oxide nanoparticles can be effectively incorporated into the structure of polyelectrolyte microcapsules made from biodegradable and nonbiodegradable polymers. The structure and morphology of synthesized microcapsules were investigated and analyzed using confocal laser scanning microscopy, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and UV/vis spectroscopy. Results of experiments in vitro on B50 neuroblastoma cells confirmed nanoceria delivery into the cell while maintaining their antioxidant properties. The results presented confirm polyelectrolyte microcapsules to be an efficient intracellular deliver...

Cerium oxide (CeO2) nanoparticles are regarded as one of the most promising materials for biomedical applications. Due to their antioxidant activity CeO2 nanoparticles are capable of protecting cells from oxidative stress induced by various physical or chemical factors. In this paper we have investigated the protective effect of CeO2 nanoparticles in the model of oxidative stress induced by low-temperature argon plasma, which is characterized by multiply damaging factors, including different types of radiation (ultraviolet and infrared), free radicals and reactive oxygen species. It was shown that citrate-stabilized cerium oxide nanoparticles protect primary embryonic mouse fibroblasts from the action of plasma, maintaining a high level of cell viability.

One of the main reasons for limiting the widespread clinical use of mesenchymal stem cells (MSCs) is a low speed of their proliferation in vitro. In this regard, the search for new safe and effective growth stimulants is an urgent task. In this study, we investigated the effect of nanocrystalline cerium oxide doped with gadolinium (Ce1-х Gdх Oy), on the morphofunctional characteristics and proliferative activity of MSCs derived from dental pulp. It was shown that the introduction of Ce1-х Gdх Oy nanoparticles into the culture of dental MSCs provides the activation of proliferation of the cells in a dose-dependent manner. High concentrations of Ce1-х Gdх Oy nanoparticles inhibit the proliferation of the cells; however, this does not lead to further development of apoptosis and cell death. The obtained results indicate that the nanocrystalline cerium oxide can be considered as a basis for the development of highly efficient and low-cost supplements for culturing MSCs.

Cerium oxide nanoparticles (nanoceria) are believed to be the most versatile nanozyme, showing great promise for biomedical applications. At the same time, the controlled intracellular delivery of nanoceria remains an unresolved problem. Here, we have demonstrated the radioprotective effect of polyelectrolyte microcapsules modified with cerium oxide nanoparticles, which provide controlled loading and intracellular release. The optimal (both safe and uptake efficient) concentrations of ceria-containing microcapsules for human mesenchymal stem cells range from 1:10 to 1:20 cell-to-capsules ratio. We have revealed the molecular mechanisms of nanoceria radioprotective action on mesenchymal stem cells by assessing the level of intracellular reactive oxygen species (ROS), as well as by a detailed 96-genes expression analysis, featuring genes responsible for oxidative stress, mitochondrial metabolism, apoptosis, inflammation etc. Hybrid ceria-containing microcapsules have been shown to provide an indirect genoprotective effect, reducing the number of cytogenetic damages in irradiated cells. These findings give new insight into cerium oxide nanoparticles&rsquo, protective action for living beings against ionising radiation.