Umbilical cord-derived mesenchymal stem cells secretomes promote embryo development and implantation

Successful implantation relies on high-quality blastocysts, uterine receptivity, and effective embryo-endometrium communication. This study investigated the effects of umbilical cord-derived mesenchymal stem cells (UC-MSC) secretomes on embryo development and implantation.

Trophoblastic spheroids and murine embryos were used to evaluate the impact of UC-MSC secretomes. Embryos obtained through superovulation were cultured in vitro and divided into five groups: a control group and four experimental groups treated with varying concentrations of UC-MSC secretomes (2.5, 5, 10, and 50 μg/mL). Embryo development competence and implantation potential were assessed in each group, and the expression levels of related genes were analyzed.

Supplementation with UC-MSC secretomes significantly enhanced trophoblast cell migration. It also stimulated endometrial cell proliferation and upregulated key implantation-related genes (LIF, LIFR, VEGFA, ITGB3, and ITGAV), improving endometrial receptivity and adhesion in trophoblastic spheroid co-cultures. While morulation rates of murine embryos remained unchanged, UC-MSC secretomes supplement significantly increased blastulation, pluripotency gene expression, and hatching rates. Supplementation with 10 and 50 μg/mL significantly increased blastocyst diameter and blastomere number, as well as embryo adhesion, outgrowth areas, and implantation rates. Additionally, growth factor analysis showed elevated VEGF-A and PDGF-AA levels in the culture media.

This study demonstrates that UC-MSC secretomes enhance both embryo development and endometrial cell function, facilitating implantation potential. These findings suggest their potential utility in supporting preimplantation embryos and improving maternal endometrial receptivity in ART.