scholarly journals The Transformative Impact of Extracellular Vesicles on Developing Sperm

Author(s):  
Michael P Rimmer ◽  
Christopher D Gregory ◽  
Rod T Mitchell

Objective To review the role of extracellular vesicles (EVs) released from the male reproductive tract and their impact on developing sperm. We discuss how sperm exiting the seminiferous tubules, although developmentally mature, require further modification. Acquisition of various functions including increased motility, transfer of cargoes and ability to undertake the acrosome reaction are mediated through the interaction between sperm and EVs. Methods A review of the literature identified that EVs are released from different portions of the male reproductive tract, notably the epididymis and prostate. These EVs interact with sperm as they pass from the seminiferous tubules to the epididymis and vas deferens prior to ejaculation. Results EVs are small lipid bound particles carrying bespoke RNA, protein and lipid cargoes. These cargoes are loaded based on the state of the parent cell and are used to communicate with recipient cells. In sperm, these cargoes are essential for post testicular modification. Sperm extracted from the proximal epididymis are poorly motile and unable to carry out the acrosome reaction. Conclusions Interaction between developing sperm and EVs is important for the subsequent function of sperm. Little is known however about EVs released from the seminiferous tubules to developing sperm or in the fetal and pre-pubertal testes. A greater understanding, especially in the formation and development of the spermatogonial stem cell niche may lead to new insights as to how damage to this niche may be prevented and preserve future fertility.

Author(s):  
Nikolaos Sofikitis ◽  
Aris Kaltsas ◽  
Fotios Dimitriadis ◽  
Jens Rassweiler ◽  
Nikolaos Grivas ◽  
...  

The therapeutic range of cyclic nucleotide phosphodiesterase 5 inhibitors (PDE5) inhibitors is getting wider in the last years. This review study focuses on the potential employment of PDE5 inhibitors as an adjunct tool for the therapeutic management of male infertility. The literature tends to suggest a beneficial effect of PDE5 inhibitors on Leydig and Sertoli cells secretory function. It also appears that PDE5 inhibitors play a role in the regulation of the contractility of the testicular tunica albuginea and the epididymis. Moreover scientific data suggest that PDE5 inhibitors enhance the prostatic secretory function leading to an improvement in sperm motility. Other studies additionally demonstrate a role of PDE5 inhibitors in the regulation of sperm capacitation process. Placebo-controlled, randomized, blind studies are necessary to unambiguously incorporate PDE5 inhibitors as an adjunct tool for the pharmaceutical treatment of semen disorders and male infertility.


1999 ◽  
Vol 11 (3) ◽  
pp. 133 ◽  
Author(s):  
A. T. Mikhailov ◽  
M. Torrado

Data on expression patterns of carboxylesterases in the male reproductive tract of different animal groups (i.e. bivalve mollusks, fruitflies and rodents) are summarized to highlight some particularly interesting questions in the context of sperm differentiation, maturation and function. The male reproduc-tive system, in spite of extreme variation in the anatomical/morphological organization in different species, is characterized by similar patterns of male-dependent carboxylesterase overexpression. The phenomenon of conserved carboxylesterase overexpression indicates similar male sex-associated functions of the enzymes. There is possible evidence of carboxylesterase recruitment by male reproductive-tract tissues indi-cating that it could be adaptive for spermatogenesis, sperm maturation and sperm use. Moreover, this idea can be extended to include a sperm cell lineage protection. This issue is discussed in the light of recent data on environmental reproductive xenobiotics that can provide a basis for a hypothetical explanation of car-boxylesterase overexpression in the male reproductive tract. Based on a well-known role of car-boxylesterases in detoxification of environmental chemicals such as organophosphate pesticides, it is proposed that various male genital tract carboxylesterases may be characterized by a similar physiological function to protect the male reproductive system against xenobiotic influences that could provoke its dys-function, thus altering sperm differentiation and maturation.


2012 ◽  
Vol 590 (17) ◽  
pp. 4209-4222 ◽  
Author(s):  
Ye Chun Ruan ◽  
Winnie W. C. Shum ◽  
Clémence Belleannée ◽  
Nicolas Da Silva ◽  
Sylvie Breton

Cells ◽  
2018 ◽  
Vol 7 (10) ◽  
pp. 153 ◽  
Author(s):  
Raquel Bernardino ◽  
David Carrageta ◽  
Ana Silva ◽  
Giuseppe Calamita ◽  
Marco Alves ◽  
...  

High 17β-Estradiol (E2) levels are known to cause alterations of spermatogenesis and environments throughout the male reproductive tract. Sertoli cells (SCs) ensure an adequate environment inside the seminiferous tubule. Glycerol stands as essential for the maintenance of blood–testis barrier created by SCs, however, the role of E2 in this process is not known. Herein, we hypothesized that the effect of E2 on glycerol permeability in mouse SCs (mSCs) could be mediated by aquaglyceroporins. The expression of aquaglyceroporins was assessed by RT-PCR and qRT-PCR. Glycerol permeability was evaluated by stopped-flow light scattering. We were able to identify the expression of AQP3 and AQP9 in mSCs where AQP9 is more abundant than AQP3. Our results show that high E2 levels decrease AQP9 mRNA abundance with no influence on AQP3 in mSCs. Interestingly, high E2 levels decreased mSCs’ permeability to glycerol, while downregulating AQP9 expression, thus suggesting a novel mechanism by which E2 modulates fluid secretion in the testis. In conclusion, E2 is an important regulator of mSCs physiology and secretion through changes in AQP9 expression and function. Thus, alterations in glycerol permeability induced by E2 may be the cause for male infertility in cases associated with the presence of high E2 levels.


2007 ◽  
Vol 104 (18) ◽  
pp. 7688-7692 ◽  
Author(s):  
Betsy Navarro ◽  
Yuriy Kirichok ◽  
David E. Clapham

Mature mammalian spermatozoa are quiescent in the male reproductive tract. Upon ejaculation and during their transit through the female reproductive tract, they undergo changes that enable them to fertilize the egg. During this process of capacitation, they acquire progressive motility, develop hyperactivated motility, and are readied for the acrosome reaction. All of these processes are regulated by intracellular pH. In the female reproductive tract, the spermatozoan cytoplasm alkalinizes, which in turn activates a Ca2+-selective current (ICatSper) required for hyperactivated motility. Here, we show that alkalinization also has a dramatic effect on membrane potential, producing a rapid hyperpolarization. This hyperpolarization is primarily mediated by a weakly outwardly rectifying K+ current (IKSper) originating from the principal piece of the sperm flagellum. Alkalinization activates the pHi-sensitive IKSper, setting the membrane potential to negative potentials where Ca2+ entry via ICatSper is maximized. IKSper is one of two dominant ion currents of capacitated sperm cells.


1996 ◽  
Vol 8 (7) ◽  
pp. 1097 ◽  
Author(s):  
PD Zalewski ◽  
X Jian ◽  
LL Soon ◽  
WG Breed ◽  
RF Seamark ◽  
...  

The Zn(II)-specific fluorophore Zinquin was used to determine the regional distribution of free or loosely-bound Zn(II) in mouse spermatozoa. Spermatozoa from the testes exhibited bright fluorescence over the entire head; those from the caput epididymides generally fluoresced more brightly in the post-acrosomal region; and spermatozoa from the caudae epididymides fluoresced less brightly, with foci of fluorescence over the sperm head which were lost after extraction with Triton X-100 and hence appeared to be membrane-associated. Treatment of cauda sperm with sodium dodecyl sulfate resulted in a bright uniform Zinquin fluorescence in the heads, similar to that observed in caput sperm, indicating that the two types of sperm have similar amounts of head Zn(II) but that the availability of Zn(II) for binding Zinquin is different. By contrast, the intensity of tail fluorescence was similar in spermatozoa from different regions of the male reproductive tract and was largely unaffected by Triton X-100 extraction, consistent with an intracellular location. Similar differences were observed between caput sperm and cauda sperm in the rat. It is concluded that visualization and measurement of free or loosely-bound Zn(II) in subcellular compartments of spermatozoa should facilitate investigation of the role of this metal in the development and function of spermatozoa and abnormalities that might accompany infertility and Zn(II) deficiency.


2005 ◽  
Vol 35 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Robert Sullivan ◽  
Fabrice Saez ◽  
Julie Girouard ◽  
Gilles Frenette

Reproduction ◽  
2013 ◽  
Vol 146 (1) ◽  
pp. R21-R35 ◽  
Author(s):  
Robert Sullivan ◽  
Fabrice Saez

Mammalian spermatozoa are unique cells in many ways, and the acquisition of their main function, i.e. fertilization capacity, is a multistep process starting in the male gonad and ending near the female egg for the few cells reaching this point. Owing to the unique character of this cell, the molecular pathways necessary to achieve its maturation also show some specific characteristics. One of the most striking specificities of the spermatozoon is that its DNA is highly compacted after the replacement of histones by protamines, making the classical processes of transcription and translation impossible. The sperm cells are thus totally dependent on their extracellular environment for their protection against oxidative stress, for example, or for the molecular changes occurring during the transit of the epididymis; the first organ in which post-testicular maturation takes place. The molecular mechanisms underlying sperm maturation are still largely unknown, but it has been shown in the past three decades that extracellular vesicles secreted by the male reproductive tract are involved in this process. This review will examine the roles played by two types of naturally occurring extracellular vesicles, epididymosomes and prostasomes, secreted by the epididymis and the prostate respectively. We will also describe how the use of artificial vesicles, liposomes, contributed to the study of male reproductive physiology.


2019 ◽  
Vol 38 (8) ◽  
pp. 899-913 ◽  
Author(s):  
NP de Souza ◽  
AP Ferragut Cardoso ◽  
LMM Gomide ◽  
TRR Lima ◽  
HA Miot ◽  
...  

Cryptorchidism (CPT), the most common male congenital abnormality, is variably associated with other male reproductive tract problems. We evaluated if cryptorchid rats develop enhanced testicular susceptibility to dibutyl phthalate (DBP) or acrylamide (AA) after extended exposure. Three studies with rats were performed: (1) in utero and postnatal exposure to DBP or AA; (2) establishment of CPT and orchiopexy; and (3) in utero and postnatal exposures to DBP or AA associated with CPT/orchiopexy. Seminiferous tubules were histologically scored according to the severity of lesions: (1) Rats exposed to DBP (score 1.5) or AA (score 1.1) presented mostly preserved spermatogenesis. Some seminiferous tubules showed vacuolated germinative epithelium, germ cell apoptosis, and a Sertoli cell-only (SCO) pattern. (2) CPT (score 3.3) resulted in decreased absolute testes weights, degenerated and SCO tubules, and spermatogenesis arrest that were reversed by orchiopexy (score 1.1). (3) Exposure to DBP or AA with CPT/orchiopexy led to atrophic testes, spermatogenesis arrest, germ cell exfoliation/multinucleation, and SCO tubules (both chemicals score 2.5). Exposure to chemicals such as DBP or AA prevented the recovery of cryptorchid testes by orchiopexy. The possible role of environmental contaminants should be considered when looking for factors that modulate human testicular disorders associated with CPT.


Author(s):  
E. R. Simpson ◽  
S. McPherson ◽  
M. Jones ◽  
K. Robertson ◽  
W. C. Boon ◽  
...  

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