Feasibility Of Cerium Oxide Nanoparticles As Renal Protective CT Contrast Agent

Background and purpose: Enhanced CT has become one of the commonly used clinical imaging examination methods,but there is a risk of post-contrast acute renal injury(PC-AKI)due to the use of iodinecontaining contrast agent,which has become the third major cause of hospital acquired AKI.Cerium oxide nanoparticles(CNPs)have attracted extensive attention because of their special physical and chemical properties(such as redox activity and oxygen buffering ability).Their various enzyme mimetic activities and broad-spectrum free radical scavenging ability may bring new directions for the treatment of PC-AKI.In this study,ultra-small ceria nanoparticles(CNPs)were synthesized to explore their renal function protection and CT imaging efficiency in vitro and in mice PC-AKI model,and put forward the hypothesis that the CNPs is expected to become renal protective CT contrast agent.Methods>CNPs were prepared by simple stirring and their free radical scavenging ability and enzyme mimetic activities in vitro were detected.At the cellular level,the mechanism of CNPs reducing oxidative damage induced by iodine contrast agent was studied.At the animal level,PC-AKI mice model was constructed to explore the mechanism of CNPs alleviating PC-AKI from the perspectives of oxidative stress and inflammatory response,as well as the feasibility and efficacy of energy spectrum imaging as CT contrast agent.Results>The synthesized CNPs(～4nm)was characterized by various methods to determine its physicochemical structure,with broad-spectrum free radical scavenging ability and enzyme mimetic activity.It plays a renal protective role in vivo and in vitro by reducing cellular oxidative stress and inflammatory response,showing good biosafety.In addition,it has better imaging performance than clinical iodine contrast agent in energy spectrum CT in vitro.Conclusion>As an antioxidant with low biological toxicity,CNPs can effectively alleviate PC-AKI and provide theoretical basis and application reference for the treatment of other free radical related diseases.Its alternative CT imaging capability has the potential to reduce the use of iodine contrast agent for PC-AKI relief,and possessing a good prospect for clinical development.