Epididymal extracellular vesicles: from intercellular communication to cellular development.

Sperm maturation in the epididymis is a complex and critical process that enables spermatozoa to acquire their motility and fertilizing ability. The epididymis is essential for sperm maturation and storage and provides a unique microenvironment to support these physiological processes. In recent years, epididymis-derived extracellular vesicles have attracted considerable attention for their role in controlling sperm quality. To date, the specific molecular mechanisms by which epididymal extracellular vesicles mediate sperm maturation remain inadequately elucidated. Several studies have hinted that extracellular vesicles mediate intercellular communication and cellular development, mainly through biomolecules such as transport proteins, lipids, and non-coding RNAs. This review constructs the framework of the molecular composition of epididymal vesicles and explores their potential functional implication in regulating sperm maturation. We also focus on the possible mechanisms through which these vesicles contribute to fertilization and early embryonic development and evaluate recent advances and application prospects of epididymal vesicles as biomarkers for male infertility.