Seminal Plasma Proteomics and Sperm Function

Seminal plasma is the protein-rich fluid that accompanies spermatozoa at ejaculation and modulates their survival, motility and fertilising potential. Recent advances in mass spectrometry and high-throughput analyses have revealed thousands of proteins of testicular, epididymal and accessory-gland origin in the seminal plasma and in the surface and cytosolic fractions of spermatozoa. These proteomic profiles vary between ejaculate fractions and reflect the dynamic remodelling of sperm function as they transit from the cauda epididymis to the female reproductive tract. Key roles identified for seminal plasma proteins include protection against oxidative stress, modulation of capacitation, regulation of immune responses in the female tract and facilitation of sperm-oviduct binding. Extracellular vesicles present in seminal plasma carry distinct protein cargos that can interact with both spermatozoa and the female endometrium, influencing fertilisation and early embryo development. Integration of proteomic data with functional assays has begun to yield candidate biomarkers of sperm quality and in vivo fertility, with global implications for livestock breeding and assisted human reproduction.

Research from Nature Portfolio

Studies have demonstrated that inclusion of post-spermatic ejaculate fractions in boar seminal doses enhances sperm resilience to thermal stress and interaction with uterine fluid. Seminal preparations that incorporate intermediate and post-spermatic fractions showed improved progressive motility and reduced susceptibility to fluid-induced losses after five days of storage, indicating a synergistic effect of fraction-specific proteins on spermatozoal robustness. In parallel, transcriptomic profiling of the pre-ovulatory porcine female genital tract after mating or artificial insemination with either whole semen or sperm-free seminal plasma has mapped widespread genomic changes. Pathways associated with sperm transport, immune regulation, oxidative stress response and oviductal reservoir binding are modulated by seminal plasma alone, highlighting its active role in preparing the uterine and tubal environment for sperm survival and fertilisation.

Seminal Plasma Proteomics and Sperm Function publication trend

The graph below shows the total number of articles in seminal plasma proteomics and sperm function across all publications each year (not limited to Nature Index journals).

Technical terms

Seminal plasma: The acellular fluid component of semen, rich in proteins, lipids and signalling molecules, secreted by the testis, epididymis and accessory sex glands.

Proteomics: The large-scale study of proteins, their structures, functions and interactions, typically using mass spectrometry to identify and quantify protein constituents of a sample.

Extracellular vesicles: Membrane-bound particles released by cells that carry proteins, lipids and nucleic acids to facilitate intercellular communication.

Ejaculate fractions: Discrete portions of ejaculate, such as sperm-rich or post-spermatic fractions, differing in sperm concentration and seminal plasma composition.

References

1. Seminal Plasma: Relevant for Fertility?. International Journal of Molecular Sciences (2021).
2. The Proteome of Pig Spermatozoa Is Remodeled During Ejaculation* [S]. Molecular & Cellular Proteomics (2018).
3. In-depth proteomic analysis of boar spermatozoa through shotgun and gel-based methods. BMC Genomics (2018).
4. Different seminal ejaculated fractions in artificial insemination condition the protein cargo of oviductal and uterine extracellular vesicles in pig. Frontiers in Cell and Developmental Biology (2023).
5. Impact of inclusion of post-spermatic ejaculate fraction in boar seminal doses on sperm metabolism, quality, and interaction with uterine fluid. Scientific Reports (2023).
6. The role of semen and seminal plasma in inducing large-scale genomic changes in the female porcine peri-ovulatory tract. Scientific Reports (2020).