The effect of cerium dioxide nanocrystals on the prooxidant status of rat lung fibroblasts in vitro under γ-irradiation conditions

Abstract

Redox-active nanocrystals of cerium dioxide (CeO2) are of interest as antioxidants; therefore, it is relevant to study the potential ability of these nanocrystals to correct prooxidative markers in irradiated cell culture in vitro. The purpose of the study was to evaluate the effect of redox-active spherical nanocrystals of cerium dioxide on markers of oxidative stress induced by γ-irradiation in a two-dimensional culture of rat lung fibroblasts. Materials and methods. The study was performed on a monolayer of lung fibroblasts of Wistar rats. Nanocrystals were added to the nutrient medium one hour before irradiation until their final concentration in the medium of 2.5 μg/L. The cells were incubated with nanocrystals for one hour and then irradiated. The radiation dose was 0.75 Gy. The concentration of 8-isoprostane was determined by spectrophotometry. The concentration of free oxygen species and the degree of lipid peroxidation in living cells were determined by fluorimetry. Visualization and measurement of fluorescence intensity were performed by confocal laser scanning microscopy. Results. 3 hours after irradiation under the conditions of pre-incubation with CeO2 nanocrystals, the content of reactive oxygen species, the level of lipid peroxidation, and the content of 8-isoprostane were significantly decreased in rat lung fibroblast culture. At the same time, incubation with cerium dioxide nanocrystals much more effectively reduced the content of reactive oxygen species in the cytoplasm of cells than in their nuclei and nucleoli in particular. Conclusion. Preincubation of rat lung fibroblasts in vitro with СeО2 nanocrystals can significantly reduce the oxidizing effects of ionizing radiation.