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Biology of Reproduction Jul 2018Manner and roles of sperm acrosome reaction in a variety of animals were compared. (Review)
Review
Manner and roles of sperm acrosome reaction in a variety of animals were compared.
Topics: Acrosome Reaction; Animals; Female; Fertilization; Fertilization in Vitro; Humans; Male; Spermatozoa
PubMed: 29462288
DOI: 10.1093/biolre/ioy045 -
Andrologia Nov 2000The present article reviews the methods for detection and the clinical significance of the acrosome reaction. The best method for the detection of the acrosome reaction... (Review)
Review
The present article reviews the methods for detection and the clinical significance of the acrosome reaction. The best method for the detection of the acrosome reaction is electron microscopy, but it is expensive and labour-intensive and therefore cannot be used routinely. The most widely used methods utilize optical microscopy where spermatozoa are stained for the visualization of their acrosomal status. Different dyes are used for this purpose as well as lectins and antibodies labelled with fluorescence. The acrosome reaction following ionophore challenge (ARIC) can separate spermatozoa that undergo spontaneous acrosome reaction from those that are induced, making the result of the inducible acrosome reaction more meaningful. Many different stimuli have been used for the induction of the acrosome reaction with different results. The ARIC test can provide information on the fertilizing capability of a sample. The ARIC test was also used to evaluate patients undergoing in vitro fertilization since a low percentage of induced acrosome reaction was found to be associated with lower rates of fertilization. The cut-off value that could be used to identify infertile patients is under debate. Therapeutic decisions can also be made on the basis of the value of the ARIC test.
Topics: Acrosome Reaction; Humans; Male; Microscopy, Electron; Spermatozoa
PubMed: 11131842
DOI: 10.1046/j.1439-0272.2000.00359.x -
International Journal of Molecular... Nov 2023To acquire the capacity to fertilize the oocyte, mammalian spermatozoa must undergo a series of biochemical reactions in the female reproductive tract, which are... (Review)
Review
To acquire the capacity to fertilize the oocyte, mammalian spermatozoa must undergo a series of biochemical reactions in the female reproductive tract, which are collectively called capacitation. The capacitated spermatozoa subsequently interact with the oocyte zona-pellucida and undergo the acrosome reaction, which enables the penetration of the oocyte and subsequent fertilization. However, the spontaneous acrosome reaction (sAR) can occur prematurely in the sperm before reaching the oocyte cumulus oophorus, thereby jeopardizing fertilization. One of the main processes in capacitation involves actin polymerization, and the resulting F-actin is subsequently dispersed prior to the acrosome reaction. Several biochemical reactions that occur during sperm capacitation, including actin polymerization, protect sperm from sAR. In the present review, we describe the protective mechanisms that regulate sperm capacitation and prevent sAR.
Topics: Animals; Male; Female; Acrosome Reaction; Actins; Semen; Spermatozoa; Actin Cytoskeleton; Mammals; Acrosome
PubMed: 38069328
DOI: 10.3390/ijms242317005 -
Asian Journal of Andrology Sep 2000We developed tests of sperm-oocyte interaction: sperm-zona binding, zona-induced acrosome reaction, spermzona penetration and sperm-oolemma binding, using oocytes which... (Review)
Review
We developed tests of sperm-oocyte interaction: sperm-zona binding, zona-induced acrosome reaction, spermzona penetration and sperm-oolemma binding, using oocytes which failed to fertilise in clinical in vitro fertilization (IVF). Although oocyte defects contribute to failure of sperm oocyte interaction, rarely are all oocytes from one woman affected. Low or zero fertilization in standard IVF was usually caused by sperm abnormalities. Poor sperm-zona pellucida binding was frequently associated with failure of standard IVF and obvious defects of sperm motility or morphology. The size and shape of the acrosome is particularly important for sperm binding to the oocyte. The proportion of acrosome intact sperm in the insemination medium was related to the IVF rate. Inducing the acrosome reaction with a calcium ionophore reduced sperm-zona binding. Blocking acrosome dispersal with an acrosin inhibitor prevented spermzona penetration. Sperm-zona penetration was even more highly related to IVF rates than was sperm-zona binding. Some patients had low or zero fertilization rates with standard IVF but normal sperm by conventional tests and normal sperm-zona binding. Few of their sperm underwent the acrosome reaction on the surface of the zona and none penetrated the zona. In contrast, fertilization and pregnancy rates were high with intracytoplasmic sperm injection. We call this condition defective zona pellucida induced acrosome reaction. Discovery of the nature of the abnormalities in the signal transduction and effector pathways of the human zona pellucida induced acrosome reaction should result in simpler tests and treatments for the patients and also provide new leads for contraceptive development.
Topics: Acrosome Reaction; Fertilization; Humans; Zona Pellucida
PubMed: 11225975
DOI: No ID Found -
Biological Research 2011Spermatozoon acrosome reaction is an exocytotic event of the utmost importance for the development of mammalian fertilisation. Current evidence shows that the triggering... (Review)
Review
Spermatozoon acrosome reaction is an exocytotic event of the utmost importance for the development of mammalian fertilisation. Current evidence shows that the triggering of the acrosome reaction (AR) could be regulated by the action of diverse compounds, namely, metabolites, neurotransmitters and hormones. The aim of the present review is to describe the modulating effects of several compounds that have been classified as inductors or inhibitors of acrosome reaction. Among AR inductors, it is necessary to mention progesterone, angiotensin II, atrial natriuretic peptide, cathecolamines, insulin, leptin, relaxin and other hormones. Regarding the inhibitors, oestradiol and epidermal growth factor are among the substances that retard AR. It is worth mentioning that gamma-aminobutyric acid, a neurotransmitter known to be an inhibitor in the central nervous system, has been shown to induce AR. The multiple hormones located in the fluids of the female reproductive tract are also likely to act as subtle regulators of AR, constituting a fundamental aspect for the development of successful fertilisation. Finally, it is necessary to emphasise that the study of regulation exerted by hormones and other compounds on AR is essential for further understanding of mammalian reproductive biology, especially spermatozoon physiology.
Topics: Acrosome Reaction; Animals; Female; Hormones; Humans; Male; Mammals; Sperm Capacitation; Spermatozoa
PubMed: 22513418
DOI: No ID Found -
Protein & Cell Feb 2011Fertilization is a process involving multiple steps that lead to the final fusion of one sperm and the oocyte to form the zygote. One of the steps, acrosome reaction... (Review)
Review
Fertilization is a process involving multiple steps that lead to the final fusion of one sperm and the oocyte to form the zygote. One of the steps, acrosome reaction (AR), is an exocytosis process, during which the outer acrosome membrane fuses with the inner sperm membrane, leading to the release of acrosome enzymes that facilitate sperm penetration of the egg investments. Though AR has been investigated for decades, the initial steps of AR in vivo, however, remain largely unknown. A well elucidated model holds the view that AR occurs on the surface of the zona pellucida (ZP), which is triggered by binding of sperm with one of the ZP glycosylated protein, ZP3. However, this model fails to explain the large number of 'falsely' acrosome-reacted sperms found within the cumulus layer in many species examined. With the emerging evidence of cross-talk between sperm and cumulus cells, the potential significance of AR in the cumulus oophorus, the outer layer of the egg, has been gradually revealed. Here we review the acrosome status within the cumulus layer, the cross-talk between sperm and cumulus cells with the involvement of a novel sperm-released factor, NYD-SP8, and re-evaluate the importance and physiological significance of the AR in the cumulus in fertilization.
Topics: Acrosome Reaction; Cell Communication; Cumulus Cells; Female; Fertilization; Humans; Male; Membrane Proteins; Oocytes; Progesterone; Spermatozoa
PubMed: 21380641
DOI: 10.1007/s13238-011-1022-5 -
The International Journal of... 2019The acrosome reaction is induced in the sperm of Cynops pyrrhogaster immediately in response to a ligand protein called acrosome reaction-inducing substance (ARIS) in...
The acrosome reaction is induced in the sperm of Cynops pyrrhogaster immediately in response to a ligand protein called acrosome reaction-inducing substance (ARIS) in the egg jelly at fertilization, whereas a spontaneous acrosome reaction occurs time-dependently in correlation with the decline of sperm quality for fertilization. The ARIS-induced acrosome reaction was recently found to be mediated by TRPV4 in association with the NMDA type glutamate receptor, although the intracellular mediators for the acrosome reaction are largely unclear. In the present study, spontaneous acrosome reaction was significantly inhibited by Ni, RN1734, and diltiazem, which blocks Cav3.2, TRPV4 or TRPM8, and the cyclic nucleotide-gated channel, respectively. In contrast, expression of Ca-activated transmembrane and soluble adenylyl cyclases was detected in the sperm of C. pyrrhogaster by reverse transcription-polymerase chain reaction. Activator of transmembrane or soluble adenylyl cyclases (forskolin or HCO ) independently promoted spontaneous acrosome reaction, while an inhibitor of each enzyme (MD12330A or KH7) inhibited it only in the sperm with high potential for spontaneous acrosome reaction. An inhibitor of protein kinase A (H89) inhibited spontaneous acrosome reaction in a manner independent of sperm potential for spontaneous acrosome reaction. Surprisingly, KH7 significantly inhibited ARIS-induced acrosome reaction, but its effect was seen in a small percentage of sperm. H89 had no effect on ARIS-induced acrosome reaction. These results suggest that C. pyrrhogaster sperm possess multiple intracellular pathways for acrosome reaction, involving Ca permeable channels, adenylyl cyclases and PKA, and that two pathways having distinct dependencies on adenylyl cyclases may contribute to ARIS-induced acrosome reaction at fertilization.
Topics: Acrosome Reaction; Adenylyl Cyclases; Animals; Diltiazem; Female; Fertilization; Gene Expression Regulation, Enzymologic; Ion Channels; Male; Nickel; Ovum; Salamandridae; Signal Transduction; Sperm-Ovum Interactions; Spermatozoa; Sulfonamides
PubMed: 32149368
DOI: 10.1387/ijdb.190092aw -
Asian Journal of Andrology Jan 2011During mammalian fertilisation, the zona pellucida (ZP) matrix surrounding the oocyte is responsible for the binding of the spermatozoa to the oocyte and induction of... (Review)
Review
During mammalian fertilisation, the zona pellucida (ZP) matrix surrounding the oocyte is responsible for the binding of the spermatozoa to the oocyte and induction of the acrosome reaction (AR) in the ZP-bound spermatozoon. The AR is crucial for the penetration of the ZP matrix by spermatozoa. The ZP matrix in mice is composed of three glycoproteins designated ZP1, ZP2 and ZP3, whereas in humans, it is composed of four (ZP1, ZP2, ZP3 and ZP4). ZP3 acts as the putative primary sperm receptor and is responsible for AR induction in mice, whereas in humans (in addition to ZP3), ZP1 and ZP4 also induce the AR. The ability of ZP3 to induce the AR resides in its C-terminal fragment. O-linked glycans are critical for the murine ZP3-mediated AR. However, N-linked glycans of human ZP1, ZP3 and ZP4 have important roles in the induction of the AR. Studies with pharmacological inhibitors showed that the ZP3-induced AR involves the activation of the G(i)-coupled receptor pathway, whereas ZP1- and ZP4-mediated ARs are independent of this pathway. The ZP3-induced AR involves the activation of T-type voltage-operated calcium channels (VOCCs), whereas ZP1- and ZP4-induced ARs involve both T- and L-type VOCCs. To conclude, in mice, ZP3 is primarily responsible for the binding of capacitated spermatozoa to the ZP matrix and induction of the AR, whereas in humans (in addition to ZP3), ZP1 and ZP4 also participate in these stages of fertilisation.
Topics: Acrosome Reaction; Animals; Egg Proteins; Female; Humans; Male; Membrane Glycoproteins; Mice; Receptors, Cell Surface; Sperm Capacitation; Zona Pellucida; Zona Pellucida Glycoproteins
PubMed: 21042299
DOI: 10.1038/aja.2010.72 -
Biology of the Cell Jul 2000During gamete interaction, sperm acrosome reaction (AR) induced by oocyte investment is a prerequisite event for the spermatozoa to pass through the zona pellucida (ZP),... (Review)
Review
During gamete interaction, sperm acrosome reaction (AR) induced by oocyte investment is a prerequisite event for the spermatozoa to pass through the zona pellucida (ZP), fuse with and penetrate the oocyte. Progesterone (P4), secreted by cumulus cells, is an important cofactor for the occurrence of this exocytosis event. The AR results from the fusion between outer acrosomal and plasma membranes, leading to inner acrosomal membrane exposure. Binding of agonists, P4 or ZP3 glycoprotein, to plasma membrane sperm receptors activates intraspermatic signals and enzymatic pathways involved in the AR. Among the proteins or glycoproteins described as potential sperm receptors for ZP, Gi/Go protein-coupled and tyrosine kinase receptors have been described. Sperm receptors for P4 are poorly characterized, except a putative GABA(A)-like receptor. ZP- and P4-promoted AR is mediated by an obligatory intracellular calcium increase, appearing first at the acrosome equatorial segment and spreading throughout the head. The plasma membrane channels involved in calcium entry are operated by a plasma membrane depolarization and protein phosphorylations mediated by protein kinase C and tyrosine kinase protein. Part of the calcium increase could also be due to intracellular store release through IP3- and nucleotide (cAMP)-gated channels. Besides adenylate cyclase and phospholipase C activations, intracellular calcium increase also stimulates PLA2 activity and actin depolymerization, leading to membrane fusion. Evaluation of AR by staining or fluorescent probes can be useful to predict fertilization success and to direct the therapeutic strategy in male infertility.
Topics: Acrosome Reaction; Animals; Egg Proteins; Female; Fertilization; Humans; Male; Membrane Glycoproteins; Receptors, Cell Surface; Receptors, Progesterone; Spermatozoa; Zona Pellucida Glycoproteins
PubMed: 11043413
DOI: 10.1016/s0248-4900(00)01072-8 -
The relationship between acrosome reaction and polyunsaturated fatty acid composition in boar sperm.Reproduction in Domestic Animals =... May 2020This study investigated the relationship between acrosome reactions and fatty acid composition with respect to fertility in boar sperm. The acrosome reaction was induced...
This study investigated the relationship between acrosome reactions and fatty acid composition with respect to fertility in boar sperm. The acrosome reaction was induced more than 85% by 60 mM methyl-beta-cyclodextrin (MBCD), and plasma membrane integrity was significantly reduced dependent on the MBCD level in boar sperm (p < .05). The acrosome-reacted sperm exhibited significantly higher saturated fatty acids (SFAs) and lower polyunsaturated fatty acids (PUFAs) composition compared to the non-acrosome reaction group (p < .0001). In addition, the PUFAs, C22:5n-6 (docosapentaenoic acid [DPA]; p < .01) and C22:6n-3 (docosahexaenoic acid [DHA]; p < .0001) were significantly decreased, and cleavage and blastocyst formation of oocytes were significantly (p < .0001) decreased in acrosome-reacted sperm relative to non-acrosome-reacted sperm. Moreover, acrosome reaction was positively correlated with SFAs, whereas negatively correlated with PUFAs, of the PUFAs, the DPA (p = .0005) and DHA (p = <.0001) were negatively correlated with the acrosome reaction. Therefore, these results suggest that the PUFAs composition of sperm is closely involved in acrosome reaction in pigs.
Topics: Acrosome Reaction; Animals; Cell Membrane; Fatty Acids, Unsaturated; Fertilization in Vitro; Male; Oocytes; Spermatozoa; Sus scrofa; beta-Cyclodextrins
PubMed: 32108385
DOI: 10.1111/rda.13661