THERMODYNAMIC STUDY OF CERIUM OXIDE NANOPARTICLES AND THEIR EFFECTS ON CELLULAR METABOLISM

Abstract

Oxidative stress is associated with a large range of health conditions. It is caused by the accumulation of reactive oxidative species above cellular neutralization capability. Cells generally defend against oxidative stress with ROS decomposing enzymes such as superoxide dismutase and catalase. Cerium oxide nanoparticles display activity that mimics superoxide dismutase and catalase antioxidative properties, allowing them to combat oxidative stress. Oxidative stress can impair the mitochondrial function and energy output of cells, which can be measured as heat with closed ampoule isothermal microcalorimetry. Thermodynamic analysis of the cell’s response to nanoceria treatment can help improve understanding of its general medical applications. Murine macrophages of the RAW264.7 cell line were cultured in 10% FBS supplemented DMEM media with 1% AA until it reached 90-95% confluency monitored by the EVOS M5000 microscope. After establishing a baseline heat output for healthy cells using a TAM-III isothermal microcalorimeter, the heat flow was measured in cells under induced oxidative stress. MTT assay was performed with various concentrations of nanoceria to identify the optimal dosage at which its antioxidative properties are most effective. In this study, we described the effect of nanoceria on mitochondrial activity.