Preovulatory follicular fluid secretome added to in vitro maturation medium influences the metabolism of equine cumulus-oocyte complexes.
Authors: Luis-Calero Marcos, Ortiz-Rodríguez José Manuel, Fernández-Hernández Pablo, Muñoz-García Carmen Cristina, Pericuesta Eva, Gutiérrez-Adán Alfonso, Marinaro Federica, Embade Nieves, Conde Ricardo, Bizkarguenaga Maider, Millet Óscar, González-Fernández Lauro, Macías-García Beatriz
Journal: BMC veterinary research
Summary
# Editorial Summary Equine embryo production relies on in vitro maturation (IVM) of oocytes, yet commercially available maturation media fail to replicate the biochemical environment of the natural preovulatory follicle, resulting in oocytes with suboptimal developmental competence. Researchers supplemented standard IVM medium with secretome—the collection of proteins and bioactive molecules—derived from equine preovulatory follicular fluid at concentrations of 20 or 40 µg/ml, then compared metabolic and genetic responses in cumulus-oocyte complexes (COCs) collected via ovum pick-up or post-mortem recovery. The secretome supplementation modified the metabolic profile of the maturation medium and altered mRNA expression patterns within the COCs, with measurable differences between the two collection methods; oocytes exposed to follicular fluid secretome also demonstrated improved meiotic competence compared to unsupplemented controls. These findings suggest that enriching IVM media with physiologically relevant follicular secretome may enhance oocyte quality for in vitro embryo production, potentially improving success rates in equine assisted reproduction programmes. The results warrant further investigation into optimal secretome concentrations and their application across diverse donor populations and breeding contexts.
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Practical Takeaways
- •In vitro embryo production media supplementation with follicular fluid secretome may enhance oocyte developmental competence and maturation outcomes in equine reproduction programs
- •Optimization of secretome concentration (20-40 µg/ml range) could improve success rates of in vitro embryo production, particularly for commercial breeding operations using post-mortem oocyte recovery
- •This approach offers potential cost-effective improvements to standard commercial maturation media formulations without requiring live oocyte collection in all cases
Key Findings
- •Preovulatory follicular fluid secretome supplementation improved metabolic profiles of equine cumulus-oocyte complexes during in vitro maturation
- •Secretome concentrations of 20 and 40 µg/ml modulated oocyte metabolism and mRNA expression patterns compared to unsupplemented controls
- •Oocytes recovered by ovum pick-up (OPU) and post-mortem (slaughterhouse) showed differential responses to secretome supplementation