Effect of oocyte vitrification on glucose transport in mouse metaphase II oocytes

Oocyte vitrification has significantly improved the survival rate and become the mainstream method for cryopreserving oocytes. Previous studies have demonstrated that the ultrastructure, mitochondrial function, DNA methylation, and histone modification exhibit an irreversible effect after oocyte vitrification. However, little is known about the effects of oocyte vitrification on glucose transport and metabolism. This study aims to determine whether mouse oocyte vitrification causes abnormal glucose metabolism and identify a strategy to correct abnormal glucose metabolism. Furthermore, this study further investigates the effects of oocyte vitrification on glucose uptake, and glucose metabolism, and energy levels. The results indicated that vitrification significantly reduced the glucose transport activity, NADPH, glutathione, and ATP levels, and increased reactive oxygen species levels in oocytes (P < 0.01). Vitrification also reduced the expression of glucose transporter isoform 1 (GLUT1) (P < 0.01). Adding a GLUT1 inhibitor reduced the glucose uptake capacity of oocytes. Furthermore, the inclusion of vitamin C into thawing and culture solutions restored abnormal glucose transportation and metabolism and improved the survival, two-cell embryo, and blastocyst rates of the vitrified groups via parthenogenesis (P < 0.05). Overall, this method may improve the quality and efficiency of oocyte vitrification.