Fatty acid supplementation in warming solutions: Effects on the developmental competence of mouse, bovine, and human oocytes and embryos after vitrification

Abstract Research Question Does fatty acid (FA) supplementation in vitrification and warming media influence developmental competence in oocytes after vitrification and warming? Design Mouse oocytes and 4-cell embryos were vitrified and warmed with FA-supplemented solutions and cultured to the blastocyst stage. To study lipid metabolism after the vitrification procedures, quantitative real-time PCR was performed for analysing the expression of β-oxidation-related genes in mouse embryos vitrified-warmed with or without FAs. The effects of FA supplementation in the warming solutions on the developmental competence of bovine and human embryos were analysed. The blastocyst outgrowth assay was performed to evaluate the potential of human blastocysts for adhesion to fibronectin. Results The neutral lipid content of mouse oocytes in the FA supplementation group (FA 0.1% and 1%) was significantly higher than that in the FA 0% group. The developmental rate to the blastocyst stage was significantly higher in the FA 1% group than in the FA 0% group in mice. Additionally, FA supplementation in warming solution upregulated Acaa2 and Hadha in mouse embryos. Moreover, FAs significantly improved the developmental ability of bovine embryos to the blastocyst stage. The developmental ability of cleaved human embryos improved marginally and the morphological grade of the inner cell mass and trophectoderm improved significantly in the FA group. Conclusions FA supplementation in the warming solutions improved the developmental competence of the vitrified-warmed mouse oocytes by activating the β-oxidation pathway. Furthermore, FA supplementation enhanced the developmental rate to the blastocyst stage and improved morphological characteristics of bovine and human embryos vitrified at the cleavage stage.