Seminal Plasma Exosomes in Male Infertility: Roles, Mechanisms, and Applications-A Double-EdgedSword.

Exosomes, which are membrane-bound vesicles with diameters of 30 to 150 nanometers, are secreted by nearly all cell types and serve as key mediators of intercellular communication. In the male reproductive system, exosomes originating from reproductive glands, including the testes, epididymis, and prostate, transport proteins, lipids, and nucleic acids, thereby regulating sperm function, maturation, and fertilization. Exosomes facilitate intercellular communication by transporting bioactive molecules (particularly microRNAs), and are instrumental in sperm maturation, motility, and fertilization capacity. However, exosomes exhibit dual roles in male reproductive processes, as their mechanisms of action are highly context-dependent, depending on the molecules they carry and the microenvironment in which they function. This review aims to summarize the dual regulatory functions of seminal plasma exosomes in male infertility, with a focus on their roles in spermatogenesis, sperm maturation, and fertilization. Furthermore, the potential of exosomes as biomarkers for diagnosing and treating male infertility is examined. Despite the promising application of exosomes in male reproductive health, further studies are required to elucidate their mechanisms, offering new perspectives for precise interventions in male infertility and enhancing assisted reproductive technologies.