Seminal-Plasma-Mediated Effects on Sperm Performance in Humans

Abstract

Seminal plasma (SP) plays a crucial role in reproduction and contains a large number of proteins, many of which may potentially modify sperm functionality. To evaluate the effects of SP identity and its protein composition on human sperm function, we treated the sperm of several males with either their own or multiple foreign SPs in all possible sperm–SP combinations (full-factorial design). Then we recorded sperm motility and viability in these combinations and investigated whether the sperm performance is dependent on sperm and SP identity (or their interaction). Finally, we studied whether the above-mentioned sperm traits are affected by the abundance of three SP proteins, dipeptidyl peptidase-4 (DPP4), neutral endopeptidase (NEP), and aminopeptidase N (APN). The identity of the SP donor affected sperm swimming velocity, viability, and the proportion of hyperactivated sperm, but males’ own SP was not consistently more beneficial for sperm than foreign SPs. Furthermore, we show that sperm performance is also partly affected by the interaction between sperm and SP donor. Finally, we found that DPP4 and NEP levels in SP were positively associated with sperm swimming velocity and hyperactivation. Taken together, our results highlight the importance of seminal plasma as a potential source of biomarkers for diagnostics and therapeutic interventions for male-derived infertility.

Low-polarity untargeted metabolomic profiling as a tool to gain insight into seminal fluid

“…From the biological point of view, the seminal fluid carries the sperm cells (or spermatozoa) in the seminal plasma –the mix of secretions coming from seminal vesicles, prostate, and bulbourethral and periurethral glands (Drabovich et al, 2014 ). In humans, spermatozoa only account for ~ 5% of the total volume of the ejaculate and, being small cells with a minute amount of cytoplasm and the ability to move, they rely on the seminal plasma to be nourished, protected from the environment, and to fertilize the oocyte (Robertson & Sharkey, 2016 ; Schjenken & Robertson, 2020 ; Turunen et al, 2022 ). To fulfill these roles, the seminal plasma contains a large variety of nutrients, buffering ions, immunomodulators, and signaling molecules (Poiani, 2006 ).…”

Extend the Survival of Human Sperm In Vitro in Non-Freezing Conditions: Damage Mechanisms, Preservation Technologies, and Clinical Applications

“…The “bad” seminal plasma may have an abnormal pH and contain more harmful substances such as higher level of insulin-like growth factors (IGF) and prostate-specific antigen (PSA), as the consequence of accessory sexual gland diseases such as chronic prostatitis [ 180 ]. Some seminal plasma proteins were also found to be associated with sperm swimming velocity and hyperactivation [ 181 ]. In terms of the role of seminal plasma and the split ejaculate method, one of treatments to avoid the negative effect of it with the potential for the non-freezing extended preservation of human sperm is discussed in depth in the next section.…”