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The Journal of Reproduction and... Feb 2022We aimed to analyze the influence of different cellular concentrations of boar sperm suspensions on the induction of capacitation and acrosome reaction. When spermatozoa...
We aimed to analyze the influence of different cellular concentrations of boar sperm suspensions on the induction of capacitation and acrosome reaction. When spermatozoa were incubated at 100 or 200 mill/ml, significant increases in protein tyrosine phosphorylation in the p32 protein were observed, compared to those at 50 mill/ml. In addition, sperm concentration-dependent increases were observed in plasma membrane lipid disorganization (50 mill/ml vs. 200 mill/ml), induction of the acrosome reaction (50 mill/ml vs. 100 mill/ml and 200 mill/ml), and sperm viability (50 mill/ml vs. 100 mill/ml and 200 mill/ml). Our data indicate that an increase in sperm concentration stimulates the induction of capacitation and acrosome reaction in boars.
Topics: Acrosome; Acrosome Reaction; Animals; Male; Phosphorylation; Sperm Capacitation; Spermatozoa; Suspensions; Swine
PubMed: 34690211
DOI: 10.1262/jrd.2021-075 -
Pharmacogenomics Jun 2008This review deals with the pharmacological properties of an alkylated monosaccharide mimetic, N-butyldeoxynojirimycin (NB-DNJ). This compound is of pharmacogenetic... (Review)
Review
This review deals with the pharmacological properties of an alkylated monosaccharide mimetic, N-butyldeoxynojirimycin (NB-DNJ). This compound is of pharmacogenetic interest because one of its biological effects in mice - impairment of spermatogenesis, leading to male infertility - depends greatly on the genetic background of the animal. In susceptible mice, administration of NB-DNJ perturbs the formation of an organelle, the acrosome, in early post-meiotic male germ cells. In all recipient mice, irrespective of reproductive phenotype, NB-DNJ has a similar biochemical effect: inhibition of the glucosylceramidase beta-glucosidase 2 and subsequent elevation of glucosylceramide, a glycosphingolipid. The questions that we now need to address are: how can glucosylceramide specifically affect early acrosome formation, and why is this contingent on genetic factors? Here we discuss relevant aspects of reproductive biology, the metabolism and cell biology of sphingolipids, and complex trait analysis; we also present a speculative model that takes our observations into account.
Topics: 1-Deoxynojirimycin; Acrosome; Animals; Glycoside Hydrolase Inhibitors; Glycosphingolipids; Male; Mice; Mice, Inbred Strains; Models, Molecular; Molecular Structure; Pharmacogenetics; Species Specificity; Spermatogenesis; Spermatozoa
PubMed: 18518850
DOI: 10.2217/14622416.9.6.717 -
BMC Pregnancy and Childbirth Jan 2024Since the unexplained in vitro fertilization failure occurs frequently, it is of great importance and clinical value to identify potential underlying predictors. This...
PURPOSE
Since the unexplained in vitro fertilization failure occurs frequently, it is of great importance and clinical value to identify potential underlying predictors. This study aimed to explore whether the percentage of sperm with a small acrosome was correlated with unexplained in vitro fertilization failure.
METHODS
A new acrosomal function evaluation index (the percentage of sperm with a small acrosome) was introduced into the analysis of sperm morphology. The association between the index and acrosome function by acrosin activity detection test and acrosome reaction test was investigated. In addition, the correlation with unexplained in vitro fertilization failure was further explored. Finally, the ROC curve was used to analyze the diagnostic efficacy on the failure of in vitro fertilization and the cutoff value was calculated.
RESULTS
As the increasing of the percentage of sperm with a small acrosome, the value of acrosin activity, acrosome reaction rate, and in vitro fertilization rate were reduced, with a statistically significant difference (P < 0.05). The index in the low fertilization rate group was significantly higher than that in the normal fertilization rate group (P < 0.05). Finally, the results of ROC curve found that when the index was 43.5%, the sensitivity and specificity were 74.2% and 95.3%, respectively.
CONCLUSION
The percentage of sperm with a small acrosome was positively correlated with unexplained in vitro fertilization failure, which could be potentially used as a prognostic index for the failure of in vitro fertilization.
TRIAL REGISTRATION
[Ethics review acceptance No IIT20210339B].
Topics: Male; Humans; Acrosome; Acrosin; Semen; Spermatozoa; Fertilization in Vitro
PubMed: 38212716
DOI: 10.1186/s12884-023-06205-0 -
International Journal of Molecular... Feb 2021Little data exist about the physiological role of ion channels during the freeze-thaw process in mammalian sperm. Herein, we determined the relevance of potassium...
Little data exist about the physiological role of ion channels during the freeze-thaw process in mammalian sperm. Herein, we determined the relevance of potassium channels, including SLO1, and of voltage-gated proton channels (HVCN1) during mammalian sperm cryopreservation, using the pig as a model and through the addition of specific blockers (TEA: tetraethyl ammonium chloride, PAX: paxilline or 2-GBI: 2-guanidino benzimidazole) to the cryoprotective media at either 15 °C or 5 °C. Sperm quality of the control and blocked samples was performed at 30- and 240-min post-thaw, by assessing sperm motility and kinematics, plasma and acrosome membrane integrity, membrane lipid disorder, intracellular calcium levels, mitochondrial membrane potential, and intracellular O⁻ and HO levels. General blockade of K channels by TEA and specific blockade of SLO1 channels by PAX did not result in alterations in sperm quality after thawing as compared to control samples. In contrast, HVCN1-blocking with 2-GBI led to a significant decrease in post-thaw sperm quality as compared to the control, despite intracellular O⁻ and HO levels in 2-GBI blocked samples being lower than in the control and in TEA- and PAX-blocked samples. We can thus conclude that HVCN1 channels are related to mammalian sperm cryotolerance and have an essential role during cryopreservation. In contrast, potassium channels do not seem to play such an instrumental role.
Topics: Acrosome; Animals; Cryopreservation; Cryoprotective Agents; Hydrogen Peroxide; Ion Channels; Male; Membrane Potential, Mitochondrial; Potassium Channel Blockers; Potassium Channels; Semen Preservation; Sperm Motility; Sus scrofa
PubMed: 33562049
DOI: 10.3390/ijms22041646 -
Cellular and Molecular Life Sciences :... Feb 2020The sperm acrosome is a lysosome-related organelle that develops using membrane trafficking from the Golgi apparatus as well as the endolysosomal compartment. How...
The sperm acrosome is a lysosome-related organelle that develops using membrane trafficking from the Golgi apparatus as well as the endolysosomal compartment. How vesicular trafficking is regulated in spermatids to form the acrosome remains to be elucidated. VPS13B, a RAB6-interactor, was recently shown involved in endomembrane trafficking. Here, we report the generation of the first Vps13b-knockout mouse model and show that male mutant mice are infertile due to oligoasthenoteratozoospermia. This phenotype was explained by a failure of Vps13b deficient spermatids to form an acrosome. In wild-type spermatids, immunostaining of Vps13b and Rab6 revealed that they transiently locate to the acrosomal inner membrane. Spermatids lacking Vps13b did not present with the Golgi structure that characterizes wild-type spermatids and showed abnormal targeting of PNA- and Rab6-positive Golgi-derived vesicles to Eea1- and Lamp2-positive structures. Altogether, our results uncover a function of Vps13b in the regulation of the vesicular transport between Golgi apparatus, acrosome, and endolysosome.
Topics: Acrosome; Animals; Biological Transport; Golgi Apparatus; Lysosomes; Male; Mice; Mice, Knockout; Protein Transport; Spermatids; Spermatogenesis; Spermatozoa; Vesicular Transport Proteins
PubMed: 31218450
DOI: 10.1007/s00018-019-03192-4 -
European Journal of Cell Biology Jun 2023The acrosome located within the mammalian sperm head is essential for successful fertilization, as it enables the sperm to penetrate the extracellular layers of the...
The acrosome located within the mammalian sperm head is essential for successful fertilization, as it enables the sperm to penetrate the extracellular layers of the oocyte and fuse with oolemma. However, the mammalian acrosomal vesicle is no longer considered to contain only hydrolytic enzymes. Using label-free nano-scale liquid chromatography tandem mass spectrometry (nLC-MS/MS) proteomics, we identified a total of 885 proteins in the acrosome isolated from spermatozoa obtained from cauda epididymis of free-living house mice Mus musculus musculus contains a total of 885 proteins. Among these, 334 proteins were significantly enriched in the acrosome thus representing 27.3% of the whole proteome of the intact sperm. Importantly, we have detected a total of nine calycins while eight of them belong to the lipocalin protein family. In mice, lipocalins are involved in multi-level chemical communication between individuals including pheromone transport and odor perception. Using an indirect immunofluorescence assay, we demonstrated that lipocalin 5 (LCN5) is expressed in the mouse germ cells, and after completing spermatogenesis, it remains localized in the sperm acrosome until the last step of the extratesticular maturation, the acrosome reaction. The presence of lipocalins in the acrosome and acrosome-reacted sperm suggests their original role as chelators of organic and potentially toxic compounds resulting from ongoing spermiogenesis. Along with this evidence, detected mitochondrial (e.g., a subunit of the cytochrome c oxidase MTCO1) and proteasomal proteins (subunits of both 20 S core proteasome [PSMA2, PSMBs] and 19 S regulatory particle [PSMDs]) in acrosomes provide further evidence that acrosomes could also function as `waste baskets` after testicular sperm maturation.
Topics: Male; Mice; Animals; Acrosome; Proteomics; Tandem Mass Spectrometry; Semen; Spermatozoa; Proteins; Lipocalins; Mammals
PubMed: 36805822
DOI: 10.1016/j.ejcb.2023.151296 -
Fertility and Sterility Feb 1994To evaluate the acrosome reaction and its prerequisite, a calcium influx, in spermatozoa of infertile men with a high incidence of abnormal sperm forms.
OBJECTIVE
To evaluate the acrosome reaction and its prerequisite, a calcium influx, in spermatozoa of infertile men with a high incidence of abnormal sperm forms.
DESIGN
Prospective, controlled study.
SETTING
Academic tertiary assisted reproduction center.
PATIENTS
Patients (n = 14) were allocated in the study after semen evaluation showed teratozoospermia (< 14% normal sperm forms) as diagnosed by strict criteria.
INTERVENTIONS
After swim-up separation of the motile fraction, acrosome reactions were evaluated using Pisum sativum agglutinin (both spontaneously and exogenously induced with P and the calcium ionophore A23187, both at 10 microM); the intracellular-free [Ca2+]i was assessed by the fluorescent fura-2 indicator (basal and after P).
RESULTS
Patients did not show the typical P-induced wave of [Ca2+]i that was observed in controls but rather a blunted response, no response at all, or abnormal basal [Ca2+]i levels. The percent of basal acrosome reaction was significantly lower for patients versus controls postswim-up, and at 1 hour and 3 hours. Furthermore, there was a significant difference in the response of acrosome reaction to P both at 1 hour and 3 hours, with patients showing almost no response at all. However, patients' acrosome reaction response to the calcium ionophore was similar to those of fertile men.
CONCLUSION
Infertile patients with a high incidence of abnormal sperm forms as diagnosed by strict criteria have a low incidence of spontaneous acrosome reaction and a diminished P-stimulated acrosome reaction, whereas the nonspecific response to a calcium ionophore is conserved. Parallel abnormalities of [Ca2+]i were observed in patients, suggesting that these sperm populations may have a defective nongenomic P sperm receptor and/or abnormalities of other membrane transduction systems.
Topics: Acrosome; Calcimycin; Calcium; Humans; Infertility, Male; Male; Progesterone; Prospective Studies; Spermatozoa
PubMed: 8299795
DOI: 10.1016/s0015-0282(16)56530-3 -
Biology of Reproduction Aug 2020During spermiogenesis in mammals, actin filaments and a variety of actin-binding proteins are involved in the formation and function of highly specialized...
During spermiogenesis in mammals, actin filaments and a variety of actin-binding proteins are involved in the formation and function of highly specialized testis-specific structures. Actin-based motor proteins, such as myosin Va and VIIa, play a key role in this complex process of spermatid transformation into mature sperm. We have previously demonstrated that myosin VI (MYO6) is also expressed in mouse testes. It is present in actin-rich structures important for spermatid development, including one of the earliest events in spermiogenesis-acrosome formation. Here, we demonstrate using immunofluorescence, cytochemical, and ultrastructural approaches that MYO6 is involved in maintaining the structural integrity of these specialized actin-rich structures during acrosome biogenesis in mouse. We show that MYO6 together with its binding partner TOM1/L2 is present at/around the spermatid Golgi complex and the nascent acrosome. Depletion of MYO6 in Snell's waltzer mice causes structural disruptions of the Golgi complex and affects the acrosomal granule positioning within the developing acrosome. In summary, our results suggest that MYO6 plays an anchoring role during the acrosome biogenesis mainly by tethering of different cargo/membranes to highly specialized actin-related structures.
Topics: Acrosome; Acrosome Reaction; Actins; Animals; Golgi Apparatus; Immunohistochemistry; Male; Mice; Mice, Inbred C57BL; Mutation; Myosin Heavy Chains; Sperm Count; Sperm Maturation; Spermatids; Spermatogenesis
PubMed: 32412041
DOI: 10.1093/biolre/ioaa071 -
Fertility and Sterility Jun 1995To determine the relationship between acrosome reactions and hamster egg penetration after ionophore challenge in nonteratozoospermic semen samples. (Comparative Study)
Comparative Study
OBJECTIVE
To determine the relationship between acrosome reactions and hamster egg penetration after ionophore challenge in nonteratozoospermic semen samples.
SETTING
A tertiary care center, the Andrologic Clinic, Department of Internal Medicine, University of L'Aquila.
PATIENTS
Twenty-five nonteratozoospermic patients with infertile marriages and nine fertile men.
INTERVENTIONS
The hamster egg penetration assay and the acrosome reaction assessment were performed on capacitated sperm suspensions in basal conditions and after ionophore challenge with ionomycin.
MAIN OUTCOME MEASURE
The relationship between the acrosome reactions and the hamster egg penetration was analyzed.
RESULTS
Although in basal conditions the spontaneous acrosome reaction rate was not correlated with the hamster egg penetration, after ionophore challenge both the induced acrosome reaction rate and the acrosome reaction increase (induced minus spontaneous acrosome reaction rate) correlated with the hamster egg penetration. The highest correlation was observed between the induced acrosome reaction rate and the penetration index. Considering a penetration index = 2 as the threshold of a good response of the hamster egg penetration assay to the ionophore challenge, significantly lower acrosome reaction rates and increases were associated with poor hamster egg penetration. However, different penetration indexes occurred at the same level of induced acrosome reaction rate.
CONCLUSIONS
The capability of sperm to react after ionophore challenge reflects to some extent the capability of the acrosome-reacted sperm to undergo the changes of the plasma membrane that are necessary for sperm-oocyte fusion. The simple evaluation of the acrosome reactions may represent a useful complement rather than a substitute for the hamster egg penetration assay in monitoring the responses of human sperm to the ionophore challenge. An impaired inducibility of the acrosome reactions may account for poor hamster egg penetrations exhibited by nonteratozoospermic semen samples.
Topics: Acrosome; Animals; Cricetinae; Female; Humans; Ionomycin; Male; Sperm-Ovum Interactions; Spermatozoa
PubMed: 7750604
DOI: No ID Found -
Acta Veterinaria Scandinavica 2002Ninety ejaculates from a total of 76 AI boars were extended in Beltsville Thawing Solution (BTS). Boar identity, breed, weight of the ejaculate and sperm concentration...
Ninety ejaculates from a total of 76 AI boars were extended in Beltsville Thawing Solution (BTS). Boar identity, breed, weight of the ejaculate and sperm concentration were registered. Motility and acrosome integrity were assessed after storage at 16-18 degrees C for 6, 30, 54, 78, and 102 h. Storage time had a significant influence on both motility (p < 0.01) and acrosome integrity (p < 0.001). The Least Square Means for percentage of motility showed a small decline from 79.8% after 6 h of storage to 78.4% at 102 h. Motility at 78 and 102 h was significantly different from motility at 6 h (p < 0.05). The percentage of sperm cells with normal acrosomes declined throughout the experiment. The Least Square Means for 6, 30, 54, 78, and 102 h of storage were 93.9%, 90.6%, 88.0%, 84.8%, and 78.2%, respectively. The decrease in acrosome integrity from one storage time to the next was highly significant throughout the trial (p < 0.001). There was a significant influence of boar (p < 0.001) and sperm concentration (p < 0.01) on motility, while acrosome integrity was affected only by boar (p < 0.001). Breed of the boars and weight of the ejaculate did not influence the dependent variables.
Topics: Acrosome; Animals; Breeding; Cryopreservation; Male; Semen; Semen Preservation; Sperm Motility; Spermatozoa; Swine; Time Factors
PubMed: 12071116
DOI: 10.1186/1751-0147-43-49