sperm activation
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Cíl studie: Metoda aktivace spermií je moderní metodický přístup, který se v praxi používá stále více. Neustále přibývá nových studií zaměřených na metody umělé aktivace motility lidských spermií. Standardní metody výběru spermií mohou v některých případech selhat mimo jiné i proto, že jsou izolovány spermie velice mladé, které ještě nedokončily svůj vývoj. V těchto případech může mít umělá stimulace jejich pohybu pozitivní efekt a velice usnadnit a urychlit proces výběru vhodných spermií. Jako aktivační činidla se nejčastěji využívají methylxanthiny. Názory na bezpečnost použití těchto látek na spermie však nejsou jednotné. Cílem práce je prezentovat současné poznatky o umělé aktivaci motility spermií na in vitro fertilizaci a následný embryonální vývoj. Metodika: Rešerše relevantní literatury v databázích Web of Science, Scopus, PubMed/Medline. Výsledky a závěr: Z literární analýzy vyplývá, že je tato metoda bezpečná a účinná při výběru nepohyblivých spermií. Byly provedeny vědecké studie zaměřené na ověření bezpečnosti a spolehlivosti této metody. Závěrem těchto studií je pozitivní dopad tohoto způsobu výběru především u případů spermií získávaných z varletní tkáně po metodě TESE (testicular sperm extraction). V těchto případech metoda umělé aktivace spermií usnadnila a zrychlila výběr spermií před intracytoplazmatickou injekcí spermie. Aktivovány byly spermie nepoškozené, které jsou nepohyblivé z důvodu nedokončení své maturace.
Aim: The sperm activation method is a modern methodological approach that is used more and more often in practice. The number of studies focused on methods of artificial activation of human sperm motility are constantly increasing. Standard sperm selection methods can fail in some cases, among other things, because very young sperm are isolated that have not yet completed their development. In these cases, artificial stimulation of their movement can have a positive effect and greatly facilitate and faster the process of selecting suitable sperm. Methylxanthines are most often used as activating agents. However, opinions on the safety of using these substances on sperm are not uniform. The aim of the thesis is to present current knowledge about artificial activation of sperm motility for in vitro fertilization and subsequent embryonic development. Methodology: Research of relevant literature in Web of Science, Scopus, PubMed/Medline databases. Results and conclusion: The literature analysis shows that this method is safe and effective in the selection of immotile spermatozoa. Scientific studies have been conducted to verify the safety and reliability of this method. The conclusion of these studies is the positive impact of this method of selection, especially in cases of sperm obtained from testicular tissue after method testicular sperm extraction. In these cases, the method of artificial sperm activation facilitated and accelerated the selection of sperm before intracytoplasmic sperm injection. Undamaged spermatozoa, which are immobile due to incomplete maturation, were activated.
- MeSH
- fertilizace in vitro * metody MeSH
- lidé MeSH
- motilita spermií * MeSH
- spermie fyziologie MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- přehledy MeSH
Protein ubiquitination is a stable, covalent post-translational modification that alters protein activity and/or targets proteins for proteolysis by the 26S proteasome. The E1-type ubiquitin-activating enzyme (UBA1) is responsible for ubiquitin activation, the initial step of ubiquitin-protein ligation. Proteasomal proteolysis of ubiquitinated spermatozoa and oocyte proteins occurs during mammalian fertilization, particularly at the site of sperm acrosome contact with oocyte zona pellucida. However, it is not clear whether the substrates are solely proteins ubiquitinated during gametogenesis or if de novo ubiquitination also occurs during fertilization supported by ubiquitin-activating and -conjugating enzymes present in the sperm acrosome. Along this line of inquiry, UBA1 was detected in boar sperm-acrosomal extracts by Western blotting (WB). Immunofluorescence revealed accumulation of UBA1 in the nuclei of spermatogonia, spermatocytes and spermatids, and in the acrosomal caps of round and elongating spermatids. Thiol ester assays utilizing biotinylated ubiquitin and isolated sperm acrosomes confirmed the enzymatic activity of the resident UBA1. A specific UBA1 inhibitor, PYR-41, altered the remodelling of the outer acrosomal membrane (OAM) during sperm capacitation, monitored using flow cytometry of fluorescein isothiocyanate-conjugated peanut agglutinin (FITC-PNA). Although viable and motile, the spermatozoa capacitated in the presence of PYR-41, showed significantly reduced fertilization rates during in vitro fertilization (IVF; p < 0.05). Similarly, the fertilization rate was lowered by the addition of PYR-41 directly into fertilization medium during IVF. In WB, high Mr bands, suggestive of protein ubiquitination, were detected in non-capacitated spermatozoa by antibodies against ubiquitin; WB with anti-phosphotyrosine antibodies and antibodies against acrosomal proteins SPINK2 (acrosin inhibitor) and AQN1 (spermadhesin) revealed that the capacitation-induced modification of those proteins was altered by PYR-41. In summary, it appears that de novo protein ubiquitination involving UBA1 contributes to sperm capacitation and acrosomal function during fertilization.
- MeSH
- akrozom imunologie fyziologie MeSH
- akrozomální reakce MeSH
- benzoáty farmakologie MeSH
- exocytóza MeSH
- fertilizace * účinky léků MeSH
- fosfotyrosin imunologie MeSH
- furany farmakologie MeSH
- glykoproteiny analýza imunologie MeSH
- interakce spermie a vajíčka * MeSH
- kapacitace spermií * MeSH
- prasata metabolismus fyziologie MeSH
- proteiny semenné plazmy analýza imunologie MeSH
- protilátky imunologie MeSH
- pyrazoly farmakologie MeSH
- spermatocyty metabolismus MeSH
- spermatogonie metabolismus MeSH
- spermie metabolismus MeSH
- ubikvitin aktivující enzymy metabolismus MeSH
- ubikvitin imunologie MeSH
- ubikvitinace MeSH
- zona pellucida metabolismus MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
Several factors regulating activation of spermatozoon motility in Eurasian burbot, Lota lota, including osmolality, calcium (Ca2+ ) ions, and temperature were investigated. Spermatozoon motility in Eurasian burbot, Lota lota was assessed at 4 and 30°C in seminal fluid, isotonic media (with and without Ca2+ ) and hypotonic media (with and without Ca2+ ). Spermatozoa were spontaneously activated in seminal fluid at 20°C and the maximum motility was recorded at 30°C, which is out of the spawning temperature range, indicating that no risk of activation occurs during routine semen handling in artificial insemination. Initiation of spermatozoon motility in L. lota is mediated by Ca2+ and sensitivity to Ca2+ is dependent on temperature.
In mammals, integrins are heterodimeric transmembrane glycoproteins that represent a large group of cell adhesion receptors involved in cell-cell, cell-extracellular matrix, and cell-pathogen interactions. Integrin receptors are an important part of signalization pathways and have an ability to transmit signals into and out of cells and participate in cell activation. In addition to somatic cells, integrins have also been detected on germ cells and are known to play a crucial role in complex gamete-specific physiological events, resulting in sperm-oocyte fusion. The main aim of this review is to summarize the current knowledge on integrins in reproduction and deliver novel perspectives and graphical interpretations presenting integrin subunits localization and their dynamic relocation during sperm maturation in comparison to the oocyte. A significant part of this review is devoted to discussing the existing view of the role of integrins during sperm migration through the female reproductive tract; oviductal reservoir formation; sperm maturation processes ensuing capacitation and the acrosome reaction, and their direct and indirect involvement in gamete membrane adhesion and fusion leading to fertilization.
- MeSH
- integriny metabolismus MeSH
- interakce spermie a vajíčka fyziologie MeSH
- kapacitace spermií * MeSH
- lidé MeSH
- oocyty cytologie metabolismus MeSH
- spermie cytologie metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
The present study shows the roles of osmolality, calcium (Ca(2+))-potassium (K(+)) antagonist and Ca(2+) in sperm activation and flagellar beating of a sturgeon species, sterlet (Acipenser ruthenus). Sperm motility was activated at hypoosmolality relative to seminal plasma and suppressed at 175 mOsmol kg(-1). Sperm activation was totally suppressed by 0.35mM K(+), but Ca(2+) could fully reverse K(+) inhibitory effect at Ca(2+): K(+) ratio of 0.25. Neither EGTA (a chelator of Ca(2+) ions) nor nifedipine (a Ca(2+) channel blocker) prevented sperm activation. But, sperm motility and velocity were significantly decreased by EGTA, nifedipine and an inhibitor for Ca(2+)/calmodulin activated phosphodiesterase (w-7) that suggest role of Ca(2+) signaling after triggering sperm activation through hypoosmolality. Symmetric flagellar beating was also turned to asymmetric after activation in w-7, which is an evidence for modulation of Ca(2+)-binding proteins activity. Sturgeon sperm, similar to salmonids, is immotile in seminal plasma due to high K(+) concentrations, but the mechanism of sperm activation seems to be closer to other fish species where osmolality prohibits sperm activation in seminal plasma. In these species, hypoosmolality is the primary signal for sperm Ca(2+)-dependent signaling of axonemal beating.
- MeSH
- bičík spermie účinky léků metabolismus fyziologie MeSH
- blokátory kalciových kanálů farmakologie MeSH
- chelátory farmakologie MeSH
- draslík farmakologie fyziologie MeSH
- EGTA farmakologie MeSH
- motilita spermií účinky léků MeSH
- nifedipin farmakologie MeSH
- osmolární koncentrace MeSH
- proteinkinasy závislé na vápníku a kalmodulinu antagonisté a inhibitory MeSH
- rybí proteiny antagonisté a inhibitory MeSH
- ryby MeSH
- sulfonamidy farmakologie MeSH
- vápník farmakologie fyziologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Cíl: V současné době rychle přibývá nových studií o asistované aktivaci oocytů, která může výrazně zefektivnit celý proces in vitro fertilizace. Oplození oocytů konvenční metodou i pomocí intracytoplazmatické injekce spermie může selhat z důvodu nedostatečné aktivace oocytu. Důvodem bývají zejména odchylky v enzymovém vybavení spermií nebo oocytů či nefunkční aktivační kaskáda. V řadě případů lze oplození dosáhnout užitím umělé aktivace oocytů pomocí aplikace donorů vápníkových iontů na oocyty po mikroinjekci spermie. Názory na bezpečnost a spolehlivost této metody však nejsou jednotné. Cílem práce je prezentovat současné poznatky o asistované aktivaci oocytů a o jejím dopadu nejen na in vitro fertilizaci, ale také na následný embryonální a fetální vývoj. Metodika: Rešerše relevantní literatury v databázích Web of Science, Scopus a PubMed/Medline. Výsledky a závěr: Z literárních údajů i vlastních zkušeností autorů vyplývá, že je tato metoda účinná a z hlediska dalšího vývoje embrya, plodu i postnatálního vývoje bezpečná. Byly provedeny rozsáhlé metaanalýzy zaměřené na tuto metodu, které nezjistily negativní dopad nejen na embryonální a fetální vývoj jedince, ale tato metoda neměla negativní dopad ani na psychosomatický vývoj narozených dětí.
Objective: Currently, there is a rapid increase in studies on assisted oocyte activation, which can significantly improve the process of in vitro fertilization. Fertilization of oocytes by conventional methods and by intracytoplasmic sperm injection can be affected by insufficient activation of the oocyte. The reason is mainly deviations in the enzymatic equipment of sperm or oocytes or a non-functional activation cascade. In many cases, fertilization can be achieved using artificial oocyte activation by applying calcium ion donors to the oocytes after sperm microinjection. However, opinions on the safety and reliability of this method are not uniform. The aim of the thesis is to present current knowledge about assisted oocyte activation and its impact not only on in vitro fertilization, but also on subsequent embryonic and fetal development. Methodology: Research of relevant literature in Web of Science, PubMed/Medline and Scopus databases. Results and conclusions: Based on the literature data and the authors’ own experience, it follows that this method is effective and safe from the point of view of further development of the embryo, fetus and postnatal development. Extensive meta-analyses focused on this method were carried out, which did not find a negative impact not only on the embryonic and fetal development of the individual, but this method did not have associated with a negative impact on the psychosomatic development of the children.
- MeSH
- fertilizace in vitro * metody MeSH
- intracytoplazmatické injekce spermie MeSH
- lidé MeSH
- oocyty * fyziologie MeSH
- vápníkové ionofory aplikace a dávkování MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- přehledy MeSH
The effect of extracellular sperm ubiquitination was examined from many aspects and the majority of existing studies negatively correlated the amount of highly ubiquitinated sperm cells in the sample with the ejaculate quality and the fertilization success rate. In the present study, we compared an early embryonic development up to blastocyst stage in the pig using two defined sperm cell populations sorted by flow cytometry (FACS) based on the rate of the extracellular ubiquitination. This novel approach allows studying the direct effect of extracellular ubiquitin (eUb), which is a marker for epididymal recognition and degradation of defective sperm cells. We further examined the hypothesis that eUb could be recognized directly in the ooplasm. In the porcine model, the significance of results might be seriously affected by a high variability among sperm cell doses from individual boars as well as by the variability among separate sample collections. To overcome this obstacle, we used cryopreserved sperm cells from a single dose. Comparison of an early embryonic development employing intracytoplasmic sperm cell injection (ICSI) with cryopreserved (frozen/thawed, F/T) and fresh sperm cells did not reveal significant difference regarding blastocyst formation rate. We also observed no difference in the male and female pronuclei formation and the first zygote cleavage after fertilization of oocytes with high or non-ubiquitinated sperm cells sorted by FACS. However, results of the early embryonic development to the blastocyst stage showed the difference between both experimental groups (16.67% of blastocysts in non-ubiquitinated group vs. 6.20% of blastocyst in the high-ubiquitinated group, P < 0.001). We further confirmed the negative effect of eUb by the masking of Ub epitopes with the appropriate primary antibody in fresh sperm cells prior to ICSI. This procedure improved the blastocyst formation rate from 14.19% in the untreated group to 24.03% concerning antibody masked sperms (P < 0.01). We conclude our results support a generally accepted hypothesis concerning the negative correlation of the presence of eUb on the sperm cell membrane and developmental competence of fertilized oocytes. However, experiments with masking Ub antibody indicate the direct negative effect of the membrane ubiquitin rather than sperm cell quality on the early embryonic development to the blastocyst stage, at least in the porcine model.
- MeSH
- blastocysta fyziologie MeSH
- intracytoplazmatické injekce spermie veterinární MeSH
- kryoprezervace veterinární MeSH
- kultivace embrya veterinární MeSH
- oocyty fyziologie MeSH
- prasata * MeSH
- průtoková cytometrie MeSH
- spermie fyziologie MeSH
- ubikvitinace fyziologie MeSH
- uchování spermatu veterinární MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
In mammals, proteases are present in sperm acrosome and play key role in fertilization. Sturgeon sperm has an acrosome, but its physiology, biochemistry, and potential role in fertilization are unknown. In the present study, we have observed high protease activity in acidic extract of intact sperm compared to that of seminal plasma in sterlet (Acipenser ruthenus). The protease activity was decreased and increased in acidic extract of motility-activated sperm and in the activation medium, respectively. Molecular analysis revealed total protease and serine (acrosin) protease activities in sperm acidic extract which was accumulated in a protein band with relative molecular mass of 35 kDa. Immunoelectron microscopy using an affinity-purified polyclonal antibody for boar acrosin localized the protease at the acrosome region. Moreover, initiation of sperm motility was inhibited after activation in the presence of inhibitors for both trypsin-like and chymotrypsin-like proteases, while the effects of protease inhibitors on sperm velocity were uncertain. Our results indicate similarities in physiology and biochemistry of acrosome between sturgeon and mammals and suggest potential role of protease in the initiation of sperm motility in sturgeon.
- MeSH
- akrosin metabolismus MeSH
- akrozom enzymologie MeSH
- analýza rozptylu MeSH
- histologické techniky veterinární MeSH
- imunoelektronová mikroskopie veterinární MeSH
- inhibitory proteas farmakologie MeSH
- motilita spermií účinky léků fyziologie MeSH
- neparametrická statistika MeSH
- proteasy farmakologie MeSH
- rosanilinová barviva MeSH
- ryby fyziologie MeSH
- sperma enzymologie MeSH
- spermie účinky léků enzymologie fyziologie MeSH
- tosylfenylalanylchlormethylketon farmakologie MeSH
- tosyllysinchlormethylketon farmakologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Fish sperm cryopreservation is a well-established technique allowing for artificial insemination on a commercial scale. The extent of proteome alterations in seminal plasma and sperm due to cryopreservation, however, is not known. This study was conducted to evaluate the effect of cryopreservation on motility variables of sterlet Acipenser ruthenus sperm and to detect the differences in protein profiles of fresh and cryopreserved sterlet sperm and seminal plasma. Fresh sperm had 89 ± 3% motility and 160 ± 14 μm/s curvilinear velocity at 15 s post-activation. The motility rate of cryopreserved sperm (37 ± 5%) was less at 15 s post-activation. No difference (ANOVA; P > 0.05) in mean curvilinear velocity of fresh and cryopreserved sperm was detected. The protein profiles of seminal plasma and sperm were characterized using comparative proteomics to determine the influence of cryopreservation. Six altered protein spots in seminal plasma and thirteen altered spots in sperm were detected in fresh and thawed sperm. Subsequent protein characterization suggested that the proteins identified were involved in sperm metabolism, cytoskeleton, and stress response. The results broaden the understanding of the effects of cryopreservation and identify the proteins associated with cryo-injury. These data may help to determine the function of altered proteins and provide new insights into improving sperm cryopreservation.
- MeSH
- kryoprezervace veterinární MeSH
- motilita spermií * MeSH
- proteom * MeSH
- ryby fyziologie MeSH
- spermie fyziologie MeSH
- transkriptom MeSH
- uchování spermatu veterinární MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Sperm capacitation, the ultimate maturation event preparing mammalian spermatozoa for fertilization, was first described in 1951, yet its regulatory mechanisms remain poorly understood. The capacitation process encompasses an influx of bicarbonate and calcium ions, removal of decapacitating factors, changes of pH and sperm proteasomal activities, and the increased protein tyrosine phosphorylation. Here, we document a novel biological phenomenon of a unique zinc (Zn2+) ion redistribution associated with mammalian sperm in vitro capacitation (IVC). Using image-based flow cytometry (IBFC), we identified four distinct types of sperm zinc ion distribution patterns (further zinc signature) and their changes during IVC. The zinc signature was altered after sperm capacitation, reduced by proteasomal inhibitors, removed by zinc chelators, and maintained with addition of external ZnCl2. These findings represent a fundamental shift in the understanding of mammalian fertilization, paving the way for improved semen analysis, in vitro fertilization (IVF), and artificial insemination (AI).
- MeSH
- analýza spermatu MeSH
- chelátory farmakologie MeSH
- chloridy farmakologie MeSH
- kapacitace spermií účinky léků fyziologie MeSH
- kationty dvojmocné metabolismus MeSH
- prasata MeSH
- průtoková cytometrie metody MeSH
- sloučeniny zinku farmakologie MeSH
- spermie metabolismus MeSH
- zinek metabolismus MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
