scholarly journals Localization of sperm intracellular Ca2+ keeps fertilizability in the newt vas deferens

Reproduction ◽  
2020 ◽  
Vol 159 (3) ◽  
pp. 339-349
Author(s):  
Nanae Makino ◽  
Nozomi Sato ◽  
Eriko Takayama-Watanabe ◽  
Akihiko Watanabe
Keyword(s):  
Sperm Motility ◽  
Salt Solution ◽  
Acrosome Reaction ◽  
Vas Deferens ◽  
Sperm Quality ◽  
Ethylene Glycol Tetraacetic Acid ◽  
Channel Blockers ◽  
Tetraacetic Acid ◽  
Intracellular Ca ◽  
Principal Piece

Sperm intracellular Ca2+ is crucial for the induction of sperm-egg interaction, but little is known about the significance of Ca2+ maintenance prior to induction. In sperm of the newt Cynops pyrrhogaster, intracellular Ca2+ is localized to the midpiece during storage in the vas deferens, while extracellular Ca2+ is influxed in modified Steinberg’s salt solution to promote a spontaneous acrosome reaction related to the decline of sperm quality. In the present study, sperm from the vas deferens were loaded with the Ca2+ indicator Fluo8H, and changes in Ca2+ localization in modified Steinberg’s salt solution were examined. Calcium ions expanded from the cytoplasmic area of the midpiece to the entire tail in most sperm during a 1-h incubation and localized to the principal piece in some sperm within 24 h. Similar changes in Ca2+ localization were observed in reconstructed vas deferens solution that included ions and pH at equivalent levels to those in the vas deferens fluid. Sperm with Ca2+ localization in the entire tail or the principal piece weakened or lost responsiveness to sperm motility-initiating substances, which trigger sperm motility for fertilization, but responded to a trigger for acrosome reaction. The change in Ca2+ localization was delayed and transiently reversed by ethylene glycol tetraacetic acid or a mixture of Ca2+ channel blockers including Ni2+ and diltiazem. These results suggest that C. pyrrhogaster sperm localize intracellular Ca2+ to the midpiece through Ca2+ transport in the vas deferens to allow for responses to sperm motility-initiating substances.

scholarly journals Roles of extracellular ions and pH in 5-HT-induced sperm motility in marine bivalve

Reproduction ◽  
2014 ◽  
Vol 147 (3) ◽  
pp. 331-345 ◽  
Author(s):  
Sayyed Mohammad Hadi Alavi ◽  
Natsuki Matsumura ◽  
Kogiku Shiba ◽  
Naoki Itoh ◽  
Keisuke G Takahashi ◽  
...  
Keyword(s):  
Sperm Motility ◽  
Pacific Oyster ◽  
Manila Clam ◽  
Marine Bivalve ◽  
Channel Blockers ◽  
Inhibitory Effects ◽  
Patinopecten Yessoensis ◽  
Independent Mechanism ◽  
Intracellular Ca ◽  
Extracellular Ions

Factors that inhibit and stimulate the initiation of sperm motility were determined for Manila clam (Ruditapesphilippinarum), Pacific oyster (Crassostrea gigas), and Japanese scallop (Patinopecten yessoensis). Compared with artificial seawater (ASW), serotonin (5-hydroxytryptamine creatinine sulfate, 5-HT) could fully trigger sperm motility and increase sperm velocity and motility duration. Sperm motility was decreased in ASW at pH 6.5–7.0 and suppressed at pH 4.0. In Manila clam and Pacific oyster, 5-HT could overcome the inhibitory effects of acidic pH on sperm motility. In the presence of nigericin (a K+/H+exchanger), sperm motility was only triggered at pH 8.3. Testicular fluid K+concentrations were two- to fourfold higher than that in ASW. Sperm motility and velocity were decreased in ASW or 5-HT containing ≥40 mM K+or ≥2.5 mM 4-aminopyridine, suggesting K+efflux requirement to initiate motility. Sperm motility and velocity were reduced in ASW or 5-HT containing EGTA or W-7, suggesting that extracellular Ca2+is required for Ca2+/calmodulin-dependent flagellar beating. Ca2+influx occurs via Ca2+channels because sperm motility and velocity were decreased in both ASW and 5-HT containing T-type and L-type Ca2+channel blockers. 5-HT-dependent initiation of sperm motility was associated with intracellular Ca2+rise, which was comparable to that seen in ASW but was not observed in the presence of EGTA or a Ca2+channel blocker. Extracellular Na+is also essential for sperm motility initiation via regulation of Na+/Ca2+exchange. Overall, 5-HT-dependent initiation of sperm motility in marine bivalve mollusks is an osmolality-independent mechanism and regulated by extracellular pH, K+, Ca2+, and Na+.

scholarly journals IMPACT OF AMPK ACTIVATOR METFORMIN ON SPERM QUALITY

2018 ◽  
Vol 15 (4) ◽  
pp. 605-615
Author(s):  
Nguyen Thi Mong Diep ◽  
Elisabeth Blesbois
Keyword(s):  
Sperm Motility ◽  
Acrosome Reaction ◽  
Positive Impact ◽  
Sperm Quality ◽  
Fluorescent Intensity ◽  
Freeze Thaw ◽  
The Media ◽  
Cryopreserved Sperm ◽  
Amp Activated Protein Kinase

Semen cryopreservation allows crucial management of animal genetic diversity. However, the freeze-thaw process causes biochemical and physical alterations, impairing sperm energy-dependent functions. Currently, many chemicals are added to the media to enhance frozen-thawed sperm quality during artificial insemination. The aims of this study was to determine the effects of Metformin (Metf) on fresh chicken sperm motility and ability to perform acrosome reaction, and to evaluate Metf’s effects on the functions of cryopreserved sperm. Chicken semen was diluted and incubated at 35°C in media supplemented with or without different doses of 5’-AMP-Activated Protein Kinase (AMPK) activator, Metf (0,5 to 5 mM). We then looked for the concentration improving the most sperm quality to use it in the cryopreservation media used for chicken sperm. Our results show that 1 mM Metf is the concentration giving the best results regarding sperm quality. AMPKα phosphorylation, viability, acrosome reaction ability (AR), and various motility parameters, were negatively affected by the freeze-thaw process, and that Metf partially restored them. Sperm quality improved (mean increased by 23% for motility, by 10% for viability) as well as AMPKα phosphorylation (mean increased by 30%). Moreover, fluorescent intensity levels of phospho-AMPK were also stronger with Metf than in the control. These results show that the presence of Metf in fresh semen has a positive impact on the quality of sperm and helps reducing the gradual decline in sperm motility caused by cryopreservation by partially restoring several essential sperm functions, and thus leads to a better overall quality of cryopreserved sperm.

scholarly journals Glutathione supplementation in semen extender improves rabbit sperm attributes during refrigeration

2021 ◽  
Vol 29 (2) ◽  
pp. 81
Author(s):  
Ejaz Ahmad ◽  
Zahid Naseer ◽  
Melih Aksoy
Keyword(s):  
Sperm Motility ◽  
Acrosome Reaction ◽  
Reaction Rate ◽  
Sperm Quality ◽  
Final Concentration ◽  
Sperm Viability ◽  
Acrosome Integrity ◽  
Semen Extender ◽  
Sperm Motion ◽  
Artificial Vagina

In the present study, we evaluated the sustaining effect of various glutathione (GSH) concentrations in extender on rabbit sperm attributes during storage at 5°C for 24 h. Semen was collected from regular donor rabbit bucks using an artificial vagina and initially evaluated for sperm quality. The qualifying ejaculates were diluted with one of the extenders having 0, 1, 2, 4 or 8 mM GSH, to achieve a final concentration of 1×108 sperm/mL. The extended samples were stored at 5°C for 24 h. Sperm motility, motion kinetics, acrosome integrity and viability were assessed after 3, 6, 12 and 24 h of storage. The results showed that total sperm motility and sperm motion kinetics (oscillation index of the sperm, straightness index and beat cross frequency) were influenced (<em>P</em>&lt;0.05) by glutathione dose and refrigeration time. An interaction of (<em>P</em>&lt;0.05) GSH concentrations and refrigeration time was observed for sperm viability and acrosome reaction rate. In conclusion, the 4 mM GSH supplemented extender’s protective influence was remarkable to maintainrabbit sperm quality for 24 h 5°C.

scholarly journals Increases in endothelial Ca2+ activate KCa channels and elicit EDHF-type arteriolar dilation via gap junctions

2002 ◽  
Vol 282 (5) ◽  
pp. H1760-H1767 ◽  
Author(s):  
Zoltan Ungvari ◽  
Anna Csiszar ◽  
Akos Koller
Keyword(s):  
Nitric Oxide ◽  
Skeletal Muscle ◽  
Gap Junctions ◽  
Palmitoleic Acid ◽  
Gracilis Muscle ◽  
Channel Blockers ◽  
Tetraacetic Acid ◽  
Kca Channels ◽  
Intracellular Ca ◽  
Coupling Time

In skeletal muscle arterioles, the pathway leading to non-nitric oxide (NO), non-prostaglandin-mediated endothelium-derived hyperpolarizing factor (EDHF)-type dilations is not well characterized. To elucidate some of the steps in this process, simultaneous changes in endothelial intracellular Ca2+ concentration ([Ca2+]i) and the diameter of rat gracilis muscle arterioles (∼60 μm) to acetylcholine (ACh) were measured by fura 2 microfluorimetry (in the absence of NO and prostaglandins). ACh elicited rapid increases in endothelial [Ca2+]i (101 ± 7%), followed by substantial dilations (73 ± 2%, coupling time: 1.3 ± 0.2 s) that were prevented by endothelial loading of an intracellular Ca2+ chelator [1,2-bis(2-aminophenoxy)ethane- N,N,N′,N′-tetraacetic acid]. Arteriolar dilations to ACh were also inhibited by intraluminal administration of the Ca2+-activated K+ (KCa) channel blockers charybdotoxin plus apamin or by palmitoleic acid, an uncoupler of myoendothelial gap junctions without affecting changes in endothelial [Ca2+]i. The presence of large conductance KCa channels on arteriolar endothelial cells was demonstrated with immunohistochemisty. We propose that in skeletal muscle arterioles, EDHF-type mediation is evoked by an increase in endothelial [Ca2+]i, which by activating endothelial KCa channels elicits hyperpolarization that is conducted via myoendothelial gap junctions to the smooth muscle resulting in decreases in [Ca2+]i and consequently dilation.

scholarly journals Effect of Centrifugation on Motility, Sperm Capacitation and Acrosome Reaction in Soy Bean and Avocado Seed Milk Extenders of Cryopreserved Goat Spermatozoa

2017 ◽  
Vol 50 (1) ◽  
pp. 13-18
Author(s):  
James Ola Daramola
Keyword(s):  
Sperm Motility ◽  
Seminal Plasma ◽  
Acrosome Reaction ◽  
Sperm Quality ◽  
West African ◽  
West African Dwarf ◽  
Artificial Vagina ◽  
Avocado Seed

Abstract Removal of seminal plasma by centrifugation (0 centrifugation, 1 centrifugation, 2 centrifugations, 3 centrifugations) and preservation in two different tris-extenders viz., avocado seed milk (ASM) and soy bean milk (SBM) based extenders were studied for their ability to support motility, in vitro capacitation and acrosome reaction of spermatozoa obtained from West African Dwarf (WAD) goat bucks during cryopreservation. Semen samples collected with the aid of artificial vagina were centrifuged for one, two and three times. The centrifuged samples were diluted with the two tris-extenders each containing 20 mL of avocado seed milk and soybean milk and cryopreserved for 30 days. The results showed higher (P < 0.05) sperm motility (P < 0.05) with increased centrifugation times. Spermatozoa that were centrifuged had higher (P < 0.05) percentage of acrosome reaction and capacitation with increased centrifugation times compared to the control. Optimal improvement in these parameters was obtained with increased centrifugation times. The findings revealed that removal of seminal plasma by centrifugation improved sperm quality of WAD goat bucks during cryopreservation and optimum improvement was achieved consistently with 3 centrifugations.

scholarly journals Ca2+-stores in sperm: their identities and functions

Reproduction ◽  
2009 ◽  
Vol 138 (3) ◽  
pp. 425-437 ◽  
Author(s):  
Sarah Costello ◽  
Francesco Michelangeli ◽  
Katherine Nash ◽  
Linda Lefievre ◽  
Jennifer Morris ◽  
...  
Keyword(s):  
Acrosome Reaction ◽  
Somatic Cells ◽  
Functional Interaction ◽  
Mammalian Sperm ◽  
Intracellular Ca ◽  
Principal Piece ◽  
Oscillations And Waves ◽  
Molecular Components ◽  
Cellular Ca ◽  
Discrete Functions

Intracellular Ca2+stores play a central role in the regulation of cellular [Ca2+]iand the generation of complex [Ca2+] signals such as oscillations and waves. Ca2+signalling is of particular significance in sperm cells, where it is a central regulator in many key activities (including capacitation, hyperactivation, chemotaxis and acrosome reaction) yet mature sperm lack endoplasmic reticulum and several other organelles that serve as Ca2+stores in somatic cells. Here, we review i) the evidence for the expression in sperm of the molecular components (pumps and channels) which are functionally significant in the activity of Ca2+stores of somatic cells and ii) the evidence for the existence of functional Ca2+stores in sperm. This evidence supports the existence of at least two storage organelles in mammalian sperm, one in the acrosomal region and another in the region of the sperm neck and midpiece. We then go on to discuss the probable identity of these organelles and their discrete functions: regulation by the acrosome of its own secretion and regulation by membranous organelles at the sperm neck (and possibly by the mitochondria) of flagellar activity and hyperactivation. Finally, we consider the ability of the sperm discretely to control mobilisation of these stores and the functional interaction of stored Ca2+at the sperm neck/midpiece with CatSper channels in the principal piece in regulation of the activities of mammalian sperm.

scholarly journals THE EFFECT OF ERYTHROPOIETIN SUPPLEMENTATION ON SPERM MOTILITY AND MORPHOLOGY IN WISTAR RAT AFTER LIGATION RELEASE OF THE VAS DEFERENS

2019 ◽  
Vol 26 (2) ◽  
Author(s):  
Aditya Pramanta ◽  
Johan Renaldo ◽  
Doddy M Soebadi
Keyword(s):  
Sperm Motility ◽  
Vas Deferens ◽  
Sperm Quality ◽  
Wistar Rat ◽  
Cloning And Expression ◽  
Absorbable Suture ◽  
Recombinant Erythropoietin ◽  
Sperm Retrieval ◽  
Glycoprotein Hormone ◽  
Vasectomy Reversal

Objective: The patency rates after vasectomy reversal ranges from 71-97%, but there is 26-72% possibility of persistent infertility. Dysfunction or obstruction of the epididymis and oxidative stress are thought to be the important cause of male infertility by disrupting spermatozoa maturation process, causing poor sperm quality. Human erythropoietin or better known as EPO is a glycoprotein hormone that has been purified since three decades ago. Research on the EPO has evolved and become a major research topic the researchers aimed as a therapeutic agent. The cloning and expression of erythropoietin has developed recombinant erythropoietin as a drug that serves as an anti-oxidant, anti-apoptotic and anti-inflammatory. This study aimed to determine the effect of erythropoietin supplementation on sperm motility and morphology in Wistar rat after the release of the vas deferens’ ligation. Material & Methods: Twenty four male Wistar rats were randomly divided into four groups (6 each). On the vasectomy group, the vas deferens were serially ligated for 7 weeks using a non-absorbable suture. The vasectomy reversal group get the same surgical treatment and after 7 weeks the ligation were released. While as in the erythropoietin group, recombinant eryhtropoietin (1000 IU/kg) was administered intraperitoneally three times for 1 week after releasing the ligation. Normal control animals received no surgical manipulation and followed by sperm retrieval for analysis. Eosin-stained slides were prepared to assess the motility and morphology of sperm cells and observed under a light microscope. Results: Ligation of vas deferens significantly decreased sperm motility and morphology. Releasing the ligation of the vas deferens did not improve the sperm motility and morphology. Supplementing eryhtropoietin 1000 IU/kg 3 times for a week after releasing the ligation did not improve the sperm motility and morphology. Conclusion: Erythropoietin supplementation did not improve the sperm motility and morphology in Wistar rat after releasing the ligation of vas deferens.

Molecular basis of adaptive evolution of sperm motility involved in in vivo fertilization of terrestrial animals

Impact ◽  
2020 ◽  
Vol 2020 (6) ◽  
pp. 73-75
Author(s):  
Akihiko Watanabe
Keyword(s):  
Sexual Reproduction ◽  
Sperm Motility ◽  
Asexual Reproduction ◽  
Acrosome Reaction ◽  
Sperm Morphology ◽  
Adaptive Potential ◽  
Selective Pressures ◽  
The Face ◽  
Genetic Profiles

One of the unifying traits of life on this planet is reproduction, or life's ability to make copies of itself. The mode of reproduction has evolved over time, having almost certainly begun with simple asexual reproduction when the ancestral single celled organism divided into two. Since these beginnings' life has tried out numerous strategies, and perhaps one of the most important and successful has been sexual reproduction. This form of reproduction relies on the union of gametes, otherwise known as sperm and egg. Evolutionarily, sexual reproduction allows for greater adaptive potential because the genes of two unique individuals have a chance to recombine and mix in order to produce a new individual. Unlike asexual reproduction which produces genetically-identical clones of the parent individual, sex produces offspring with novel genes and combinations of genes. Therefore, in the face of new selective pressures there is a higher chance that one of these novel genetic profiles will produce an adaptation that is advantageous in the new circumstances. Dr Akihiko Watanabe is a reproductive biologist based in the Department of Biology, Faculty of Science Yamagata University in Japan, he is currently working on three research projects; a comparative study on the signalling pathways for inducing sperm motility and acrosome reaction in amphibians, the mechanism behind the adaptive modification of sperm morphology and motility, and the origin of sperm motility initiating substance (SMIS).

scholarly journals CagA-PositiveHelicobacter pyloriInfection and Reduced Sperm Motility, Vitality, and Normal Morphology

2013 ◽  
Vol 35 ◽  
pp. 229-234 ◽  
Author(s):  
E. Moretti ◽  
G. Collodel ◽  
L. Mazzi ◽  
M. S. Campagna ◽  
N. Figura
Keyword(s):  
Sperm Motility ◽  
Normal Forms ◽  
Molecular Mimicry ◽  
Sperm Quality ◽  
Semen Analysis ◽  
Normal Morphology ◽  
Partial Linear ◽  
Caga Status ◽  
The Relationship ◽  
Autoimmune Phenomena

Helicobacter pylori(HP) infection, particularly when caused by strains expressing CagA, may be considered a concomitant cause of male and female reduced fertility. This study explored, in 87 HP-infected males, the relationship between infection by CagA-positive HP strains and sperm parameters. HP infection and CagA status were determined by ELISA and Western blotting; semen analysis was performed following WHO guidelines. The amino acid sequence of human enzymes involved in glycolysis and oxidative metabolism were “blasted” with peptides expressed by HP J99. Thirty-seven patients (42.5%) were seropositive for CagA. Sperm motility (18% versus 32%; ), sperm vitality (35% versus 48%; ) and the percentage of sperm with normal forms (18% versus 22%; ) in the CagA-positive group were significantly reduced versus those in the CagA-negative group. All the considered enzymes showed partial linear homology with HP peptides, but four enzymes aligned with four different segments of the samecagisland protein. We hypothesize a relationship between infection by strains expressing CagA and decreased sperm quality. Potentially increased systemic levels of inflammatory cytokines that occur in infection by CagA-positive strains and autoimmune phenomena that involve molecular mimicry could explain the pathogenetic mechanism of alterations observed.

scholarly journals PACAP-mediated sperm–cumulus cell interaction promotes fertilization

Reproduction ◽  
2011 ◽  
Vol 141 (2) ◽  
pp. 163-171 ◽  
Author(s):  
Ichiro Tanii ◽  
Tadashi Aradate ◽  
Kouhei Matsuda ◽  
Akira Komiya ◽  
Hideki Fuse
Keyword(s):  
Sperm Motility ◽  
Acrosome Reaction ◽  
Cumulus Cell ◽  
Cumulus Cells ◽  
Cell Interaction ◽  
Fertilization Rate ◽  
Type I ◽  
Dependent Manner ◽  
Sperm Penetration

The developing acrosome in spermatids contains pituitary adenylate cyclase-activating polypeptide (PACAP). However, the role of the acrosomal PACAP remains unclear because it has not been detected in mature spermatids and sperm. We reinvestigated whether the sperm acrosome contains PACAP. An antiserum produced against PACAP reacted to the anterior acrosome in epididymal sperm fixed under mild conditions, suggesting that PACAP acts on oocytes and/or cumulus cells at the site of fertilization. Immunolabeling and RT-PCR demonstrated the presence of PACAP type I receptor, a PACAP-specific receptor, in postovulatory cumulus cells. To investigate the role of PACAP in fertilization, we pretreated cumulus–oocyte complexes with the polypeptide. At a low concentration of sperm, the fertilization rate was significantly enhanced by PACAP in a dose-dependent manner. Sperm penetration through the oocyte investment, cumulus layer, and zona pellucida was also enhanced by PACAP. The enhancement was probably due to an enhancement in sperm motility and the zona-induced acrosome reaction, which were stimulated by a cumulus cell-releasing factor. Indeed, PACAP treatment increased the secretion of progesterone from the cumulus–oocyte complexes. These results strongly suggest that in response to PACAP, cumulus cells release a soluble factor that probably stimulates sperm motility and the acrosome reaction, thereby promoting fertilization.

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