Effect of co-culture human endothelial progenitor cells with porcine oocytes during maturation and subsequent embryo development of parthenotes in vitro.

Human endothelial progenitor cells (EPCs) have been applied to regenerative medicine for their roles in angiogenesis as well as neovascularization, and these angiogenetic functions have beneficial effects on maturation of ovarian follicles. However, little information is available on whether EPCs on culture systems affect oocyte maturation and subsequent embryo development. Therefore, the objective of this study was to investigate the effect of EPC co-culture on porcine oocytes during in vitro maturation (IVM) and subsequent embryo development, and to examine gene expression in cumulus cells, oocytes and blastocysts. The effect of co-culture using EPC on porcine oocyte IVM was investigated. Oocytes were activated using electrical stimulation and embryo developmental competence was estimated. The expression of the genes related to cumulus expansion, oocyte maturation, embryo development, and apoptosis were analyzed. In result, there was a significantly increased maturation rate in EPC group compared with control (p < 0.05). Also, oocytes co-cultured with EPCs exhibited significantly improved blastocyst formation rates (p < 0.05). The expression of mRNAs associated with cumulus expansion and apoptosis in cumulus cells was significantly up-regulated in EPC group. Also, markedly increased levels of GDF9, BMP15, and BCL2 were observed in oocytes from the EPC group. Blastocysts in the co-culture group showed significantly higher SOX2, OCT4, and NANOG levels. In conclusion, co-culturing porcine oocytes with EPCs improves their maturation by regulating genes involved in cumulus cell expansion, oocyte maturation, and apoptosis. Moreover, EPC co-culture during IVM enhanced embryo development as shown by increased blastocyst formation rate and pluripotency-related gene expression.