Ceria Nanoparticles Improve the Quality of Aging Oocytes in Mice by Enhancing ROS Scavenging Ability

If fertilization does not occur in a timely manner after ovulation, then that can lead to aging and a decline in relation to oocyte quality, which have detrimental effects on subsequent embryo development and offspring. Reactive oxygen species (ROS) induced oxidative stress is the main factor in the deterioration of oocyte aging. Herein, ceria nanoparticles (NPs) have been developed as ROS scavengers to improve the quality of aging oocytes. We found that ceria NPs could effectively inhibit senescence-induced morphological changes and lower ROS accumulation in the oocytes. In addition, ceria NPs reduced the abnormal spindle distribution and improved mitochondrial function. Ceria NPs also reduced oxidative stress in aging oocytes by increasing ROS scavenging capacity rather than inhibiting ROS generation capacity. Furthermore, ceria NPs increased the rate of blastocyst formation in aging oocytes. We conclude that ceria NPs can enhance the quality and development potential of aging oocytes by reducing the level of oxidative stress.