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Fuentes F, Contreras MJ, Arroyo-Salvo C, Cabrera P P, Silva M, Merino O, Arias ME, Felmer R. Effect of exogenous sperm capacitation inducers on stallion sperm. Theriogenology 2024; 226:29-38. [PMID: 38824691 DOI: 10.1016/j.theriogenology.2024.05.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 05/17/2024] [Accepted: 05/28/2024] [Indexed: 06/04/2024]
Abstract
Although under appropriate laboratory conditions, sperm from different mammalian species can be capacitated in vitro, the optimal conditions for sperm capacitation in the stallion have been elusive. This study evaluated the effect of different capacitating inducers in Whitten and Tyrode media and assessed their impact on capacitation-related factors. Stallion sperm were incubated with different combinations of capacitating inducers at 38.5 °C in an air atmosphere. Sperm quality variables such as motility, mitochondrial membrane potential, and lipid peroxidation were assessed. Membrane fluidity and intracellular calcium levels were evaluated as early markers of capacitation, while tyrosine phosphorylation events and the sperm's ability to perform acrosomal exocytosis were used as late capacitation markers. Finally, these sperm were evaluated using a heterologous zona pellucida binding assay. The findings confirm that capacitating conditions evaluated increase intracellular calcium levels and membrane fluidity in both media. Similarly, including 2 or 3 inducers in both media increased tyrosine phosphorylation levels and acrosomal exocytosis after exposure to progesterone, confirming that stallion sperm incubated in these conditions shows cellular and molecular changes consistent with sperm capacitation. Furthermore, the zona pellucida binding assay confirmed the binding capacity of sperm incubated in capacitation conditions, a key step for stallion in vitro fertilization success. Further studies are needed to evaluate the effect of these conditions on in vitro fertilization in the horse.
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Affiliation(s)
- Fernanda Fuentes
- Laboratory of Reproduction, Center of Reproductive Biotechnology (CEBIOR-BIOREN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile; Doctoral Program in Applied Cellular and Molecular Biology, Universidad de La Frontera, Temuco, Chile
| | - Maria Jose Contreras
- Laboratory of Reproduction, Center of Reproductive Biotechnology (CEBIOR-BIOREN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile
| | - Camila Arroyo-Salvo
- Laboratory of Reproduction, Center of Reproductive Biotechnology (CEBIOR-BIOREN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile
| | - Paulina Cabrera P
- Laboratory of Reproduction, Center of Reproductive Biotechnology (CEBIOR-BIOREN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile
| | - Mauricio Silva
- Department of Veterinary Sciences and Public Health, Universidad Catolica de Temuco, Temuco, Chile
| | - Osvaldo Merino
- Department of Basic Sciences, Faculty of Medicine. Universidad de La Frontera, Temuco, Chile
| | - Maria Elena Arias
- Laboratory of Reproduction, Center of Reproductive Biotechnology (CEBIOR-BIOREN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile; Department of Agricultural Production, Faculty of Agriculture and Environmental Sciences, Universidad de La Frontera, Temuco, Chile
| | - Ricardo Felmer
- Laboratory of Reproduction, Center of Reproductive Biotechnology (CEBIOR-BIOREN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile; Department of Agricultural Sciences and Natural Resources, Faculty of Agriculture and Environmental Sciences, Universidad de La Frontera, Temuco, Chile.
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Arroyo-Salvo C, Río S, Bogetti ME, Plaza J, Miragaya M, Yaneff A, Davio C, Fissore R, Gervasi MG, Gambini A, Perez-Martinez S. Effect of bicarbonate and polyvinyl alcohol on in vitro capacitation and fertilization ability of cryopreserved equine spermatozoa. Andrology 2024. [PMID: 38804843 DOI: 10.1111/andr.13667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 04/26/2024] [Accepted: 05/11/2024] [Indexed: 05/29/2024]
Abstract
BACKGROUND Factors contributing to the limited success of in vitro fertilization in horses remain to be studied. In this work, we elucidated the effect of different essential capacitation media components, bicarbonate, and bovine serum albumin or polyvinyl-alcohol, and the incubation microenvironment on sperm parameters associated with capacitation, acrosome reaction, and their ability to activate oocytes via heterologous intracytoplasmic spermatozoa injection in equine cryopreserved spermatozoa. METHODS Frozen-thawed spermatozoa underwent incubation at different time intervals in either Tyrode's albumin lactate pyruvate medium (non-capacitating; NC) or Tyrode's albumin lactate pyruvate supplemented with bicarbonate, bicarbonate and polyvinyl-alcohol, bicarbonate and bovine serum albumin, polyvinyl-alcohol and bovine serum albumin alone. Protein kinase A-phosphorylated substrates and tyrosine phosphorylation levels, sperm motility, and acrosome reaction percentages were evaluated. After determining the best condition media (capacitating; CAP), heterologous intracytoplasmic spermatozoa injection on pig oocytes was performed and the phospholipase C zeta sperm localization pattern was evaluated. RESULTS Incubation of frozen-thawed equine spermatozoa with bicarbonate and polyvinyl-alcohol in atmospheric air for 45 min induced an increase in protein kinase A-phosphorylated substrates and tyrosine phosphorylation levels compared to NC condition. Sperm incubation in bicarbonate and polyvinyl-alcohol medium showed an increase in total motility and progressive motility with respect to NC (p ≤ 0.05). Interestingly, three parameters associated with sperm hyperactivation were modulated under bicarbonate and polyvinyl-alcohol conditions. The kinematic parameters curvilinear velocity and amplitude of lateral head displacement significantly increased, while straightness significantly diminished (curvilinear velocity: bicarbonate and polyvinyl-alcohol = 120.9 ± 2.9 vs. NC = 76.91 ± 6.9 µm/s) (amplitude of lateral head displacement: bicarbonate and polyvinyl-alcohol = 1.15 ± 0.02 vs. NC = 0.77 ± 0.03 µm) (straightness: bicarbonate and polyvinyl-alcohol = 0.76 ± 0.01 vs. NC = 0.87 ± 0.02) (p ≤ 0.05). Moreover, the spontaneous acrosome reaction significantly increased in spermatozoa incubated in this condition. Finally, bicarbonate and polyvinyl-alcohol medium was established as CAP medium. Although no differences were found in phospholipase C zeta localization pattern in spermatozoa incubated under CAP, equine spermatozoa pre-incubated in CAP condition for 45 min showed higher fertilization rates when injected into matured pig oocytes (NC: 47.6% vs. CAP 76.5%; p ≤ 0.05). CONCLUSION These findings underscore the importance of bicarbonate and polyvinyl-alcohol in supporting critical events associated with in vitro sperm capacitation in the horse, resulting in higher oocyte activation percentages following heterologous intracytoplasmic spermatozoa injection. This protocol could have an impact on reproductive efficiency in the equine breeding industry.
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Affiliation(s)
- Camila Arroyo-Salvo
- Centro de Estudios Farmacológicos y Botánicos (CEFYBO), CONICET-UBA, Buenos Aires, Argentina
| | - Sofía Río
- Centro de Estudios Farmacológicos y Botánicos (CEFYBO), CONICET-UBA, Buenos Aires, Argentina
| | - María Eugenia Bogetti
- Centro de Estudios Farmacológicos y Botánicos (CEFYBO), CONICET-UBA, Buenos Aires, Argentina
| | - Jessica Plaza
- Facultad de Ciencias Veterinarias, Universidad de Buenos Aires, INITRA, Buenos Aires, Argentina
| | - Marcelo Miragaya
- Facultad de Ciencias Veterinarias, Universidad de Buenos Aires, INITRA, Buenos Aires, Argentina
| | - Agustín Yaneff
- Instituto de Investigaciones Farmacológicas (ININFA-UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Carlos Davio
- Instituto de Investigaciones Farmacológicas (ININFA-UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Rafael Fissore
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, Massachusetts, USA
| | - María Gracia Gervasi
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, Massachusetts, USA
- Department of Animal Science, University of Connecticut, Storrs, Connecticut, USA
| | - Andrés Gambini
- School of Agriculture and Food Sustainability, The University of Queensland, Gatton, Queensland, Australia
| | - Silvina Perez-Martinez
- Centro de Estudios Farmacológicos y Botánicos (CEFYBO), CONICET-UBA, Buenos Aires, Argentina
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Zhu Z, Li W, Yang Q, Zhao H, Zhang W, Adetunji AO, Hoque SAM, Kou X, Min L. Pyrroloquinoline Quinone Improves Ram Sperm Quality through Its Antioxidative Ability during Storage at 4 °C. Antioxidants (Basel) 2024; 13:104. [PMID: 38247528 PMCID: PMC10812569 DOI: 10.3390/antiox13010104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 12/25/2023] [Accepted: 01/11/2024] [Indexed: 01/23/2024] Open
Abstract
Sperm motility is an important factor in the migration of sperm from the uterus to the oviduct. During sperm preservation in vitro, sperm generates excessive ROS that damages its function. This study aims to investigate whether the addition of pyrroloquinoline quinone (PQQ) to the diluted medium could improve chilled ram sperm quality, and then elucidates the mechanism. Ram semen was diluted with Tris-citric acid-glucose (TCG) medium containing different doses of PQQ (0 nM, 10 nM, 100 nM, 1000 nM, 10,000 nM), and stored at 4 °C. Sperm motility patterns, plasma membrane integrity, acrosome integrity, mitochondrial membrane potential, reactive oxygen species (ROS) levels, malondialdehyde (MDA) levels, superoxide dismutase (SOD) activity, and ATP levels were measured after preservation. Furthermore, the expressions of NADH dehydrogenase 1 (MT-ND1) and NADH dehydrogenase 6 (MT-ND6) in sperm were also detected by western blotting. In addition, sperm capacitation and the ability of sperm to bind to the zona pellucina were also evaluated. It was observed that the addition of PQQ significantly (p < 0.05) improved ram sperm motility, membrane integrity, and acrosome integrity during preservation. The percentage of sperm with high mitochondrial membrane potential in the PQQ treatment group was much higher than that in the control. In addition, supplementation of PQQ also decreased the sperm MDA and ROS levels, while increasing ATP levels. Interestingly, the levels of MT-ND1 and MT-ND6 protein in sperm treated with PQQ were also higher than that of the control. Furthermore, the addition of 100 nM PQQ to the medium decreased ROS damage in MT-ND1 and MT-ND6 proteins. The addition of 100 nM PQQ significantly (p < 0.05) increased protein tyrosine phosphorylation in ram sperm after induced capacitation. Furthermore, the value of the sperm-zona pellucida binding capacity in the 100 nM PQQ treatment group was also much higher than that of the control. Overall, during chilled ram- sperm preservation, PQQ protected ram sperm quality by quenching the ROS levels to reduce ROS damage and maintain sperm mitochondrial function, and preserved the sperm's high ability of fertilization.
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Affiliation(s)
- Zhendong Zhu
- College of Animal Science and Technology, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao 266109, China; (Z.Z.)
| | - Wenjia Li
- College of Animal Science and Technology, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao 266109, China; (Z.Z.)
| | - Qitai Yang
- College of Animal Science and Technology, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao 266109, China; (Z.Z.)
| | - Haolong Zhao
- College of Animal Science and Technology, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao 266109, China; (Z.Z.)
| | - Weijing Zhang
- College of Animal Science and Technology, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao 266109, China; (Z.Z.)
| | - Adedeji O. Adetunji
- Department of Agriculture, University of Arkansas at Pine Bluff, Pine Bluff, AR 71601, USA
| | - S. A. Masudul Hoque
- Department of Animal Breeding and Genetics, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur 1706, Bangladesh
| | - Xin Kou
- Hongde Livestock Farm, Yingli Town, Weifang 261000, China
| | - Lingjiang Min
- College of Animal Science and Technology, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao 266109, China; (Z.Z.)
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The stallion sperm acrosome: Considerations from a research and clinical perspective. Theriogenology 2023; 196:121-149. [PMID: 36413868 DOI: 10.1016/j.theriogenology.2022.11.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 11/02/2022] [Accepted: 11/07/2022] [Indexed: 11/16/2022]
Abstract
During the fertilization process, the interaction between the sperm and the oocyte is mediated by a process known as acrosomal exocytosis (AE). Although the role of the sperm acrosome on fertilization has been studied extensively over the last 70 years, little is known about the molecular mechanisms that govern acrosomal function, particularly in species other than mice or humans. Even though subfertility due to acrosomal dysfunction is less common in large animals than in humans, the evaluation of sperm acrosomal function should be considered not only as a complementary but a routine test when individuals are selected for breeding potential. This certainly holds true for stallions, which might display lower levels of fertility in the face of "acceptable" sperm quality parameters determined by conventional sperm assays. Nowadays, the use of high throughput technologies such as flow cytometry or mass spectrometry-based proteomic analysis is commonplace in the research arena. Such techniques can also be implemented in clinical scenarios of males with "idiopathic" subfertility. The current review focuses on the sperm acrosome, with particular emphasis on the stallion. We aim to describe the physiological events that lead to the acrosome formation within the testis, the role of very specific acrosomal proteins during AE, the methods to study the occurrence of AE under in vitro conditions, and the potential use of molecular biology techniques to discover new markers of acrosomal function and subfertility associated with acrosomal dysfunction in stallions.
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Maitan P, Bromfield EG, Stout TAE, Gadella BM, Leemans B. A stallion spermatozoon's journey through the mare's genital tract: In vivo and in vitro aspects of sperm capacitation. Anim Reprod Sci 2022; 246:106848. [PMID: 34556396 DOI: 10.1016/j.anireprosci.2021.106848] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 09/03/2021] [Accepted: 09/04/2021] [Indexed: 12/14/2022]
Abstract
Conventional in vitro fertilization is not efficacious when working with equine gametes. Although stallion spermatozoa bind to the zona pellucida in vitro, these gametes fail to initiate the acrosome reaction in the vicinity of the oocyte and cannot, therefore, penetrate into the perivitelline space. Failure of sperm penetration most likely relates to the absence of optimized in vitro fertilization media containing molecules essential to support stallion sperm capacitation. In vivo, the female reproductive tract, especially the oviductal lumen, provides an environmental milieu that appropriately regulates interactions between the gametes and promotes fertilization. Identifying these 'fertilization supporting factors' would be a great contribution for development of equine in vitro fertilization media. In this review, a description of the current understanding of the interactions stallion spermatozoa undergo during passage through the female genital tract, and related specific molecular changes that occur at the sperm plasma membrane is provided. Understanding these molecular changes may hold essential clues to achieving successful in vitro fertilization with equine gametes.
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Affiliation(s)
- Paula Maitan
- Departments of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 112, 3584 CM Utrecht, The Netherlands; Department of Veterinary Sciences, Universidade Federal de Viçosa, Viçosa, MG, Brazil
| | - Elizabeth G Bromfield
- Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, The Netherlands; Priority Research Centre for Reproductive Science, College of Engineering, Science and Environment, University of Newcastle, Australia
| | - Tom A E Stout
- Departments of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 112, 3584 CM Utrecht, The Netherlands
| | - Bart M Gadella
- Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, The Netherlands; Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, The Netherlands
| | - Bart Leemans
- Departments of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 112, 3584 CM Utrecht, The Netherlands.
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Bovine ICSI: limiting factors, strategies to improve its efficiency and alternative approaches. ZYGOTE 2022; 30:749-767. [PMID: 36082429 DOI: 10.1017/s0967199422000296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Intracytoplasmic sperm injection (ICSI) is an assisted reproductive technique mainly used to overcome severe infertility problems associated with the male factor, but in cattle its efficiency is far from optimal. Artificial activation treatments combining ionomycin (Io) with 6-dimethylaminopurine after piezo-ICSI or anisomycin after conventional ICSI have recently increased the blastocyst rate obtained. Compounds to capacitate bovine spermatozoa, such as heparin and methyl-β-cyclodextrin and compounds to destabilize sperm membranes such as NaOH, lysolecithin and Triton X-100, have been assessed, although they have failed to substantially improve post-ICSI embryonic development. Disulfide bond reducing agents, such as dithiothreitol (DTT), dithiobutylamine and reduced glutathione, have been assessed to decondense the hypercondensed head of bovine spermatozoa, the two latter being more efficient than DTT and less harmful. Although piezo-directed ICSI without external activation has generated high fertilization rates and modest rates of early embryo development, other studies have required exogenous activation to improve the results. This manuscript thoroughly reviews the different strategies used in bovine ICSI to improve its efficiency and proposes some alternative approaches, such as the use of extracellular vesicles (EVs) as 'biological methods of oocyte activation' or the incorporation of EVs in the in vitro maturation and/or culture medium as antioxidant defence agents to improve the competence of the ooplasm, as well as a preincubation of the spermatozoa in estrous oviductal fluid to induce physiological capacitation and acrosome reaction before ICSI, and the use of hyaluronate in the sperm immobilization medium.
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Contreras MJ, Arias ME, Silva M, Cabrera P, Felmer R. Effect of cholestanol and cholesterol-loaded cyclodextrin on stallion sperm function and capacitation post-cryopreservation. Theriogenology 2022; 189:1-10. [PMID: 35714521 DOI: 10.1016/j.theriogenology.2022.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 05/06/2022] [Accepted: 06/06/2022] [Indexed: 10/18/2022]
Abstract
Cryopreservation of stallion semen is less efficient than other species such as bovine. This is mainly because of the greater susceptibility of stallion sperm to the freezing damage that generates oxidative stress and plasma membrane injury, resulting in DNA fragmentation and cell death. These data suggest the need to develop new strategies of sperm cryopreservation that can improve the efficiency of this technique in stallions by reducing or preventing membrane damage and cell death. The present study aimed to evaluate the effect of adding membrane stabilizers to the freezing medium and assess the quality and in vitro capacitation of stallion sperm after thawing. Semen samples from three stallions frozen with membrane stabilizers (cholesterol-loaded cyclodextrin and cholestanol-loaded cyclodextrin) were evaluated in two experiments: i) sperm quality and functional analysis after thawing, and ii) sperm quality and functional analysis after 4 h of post-thaw incubation in capacitating conditions. Plasma membrane integrity, mitochondrial membrane potential, membrane lipid disorder, intracellular Ca2+, tyrosine phosphorylation, acrosome reaction, DNA damage, sperm motility, and binding to the zona pellucida were assessed. The results showed that cholesterol-loaded cyclodextrin was the stabilizer that most efficiently reduced the membrane disruption and post-thaw cell damage. In addition, this stabilizer made it possible to obtain in vitro capacitated sperm showing higher plasma membrane integrity, mitochondrial membrane potential, sperm motility, binding to the zona pellucida and better response to in vitro capacitating conditions.
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Affiliation(s)
- María José Contreras
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera, Temuco, Chile; Doctoral Program in Applied Cell and Molecular Biology, Universidad de La Frontera, Temuco, Chile
| | - María Elena Arias
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera, Temuco, Chile; Department of Agricultural Production, Faculty of Agriculture and Forestry Sciences, Universidad de La Frontera, Temuco, Chile
| | - Mauricio Silva
- Department of Veterinary Sciences and Public Health, Universidad Catolica de Temuco, Temuco, Chile
| | - Paulina Cabrera
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera, Temuco, Chile; Doctoral Program in Applied Cell and Molecular Biology, Universidad de La Frontera, Temuco, Chile
| | - Ricardo Felmer
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera, Temuco, Chile; Department of Agricultural Sciences and Natural Resources, Faculty of Agriculture and Forestry Sciences, Universidad de La Frontera, Temuco, Chile.
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Maitan PP, Bromfield EG, Hoogendijk R, Leung MR, Zeev-Ben-Mordehai T, van de Lest CH, Jansen JWA, Leemans B, Guimarães JD, Stout TAE, Gadella BM, Henning H. Bicarbonate-Stimulated Membrane Reorganization in Stallion Spermatozoa. Front Cell Dev Biol 2021; 9:772254. [PMID: 34869370 PMCID: PMC8635755 DOI: 10.3389/fcell.2021.772254] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 10/25/2021] [Indexed: 11/13/2022] Open
Abstract
Classical in vitro fertilization (IVF) is still poorly successful in horses. This lack of success is thought to be due primarily to inadequate capacitation of stallion spermatozoa under in vitro conditions. In species in which IVF is successful, bicarbonate, calcium, and albumin are considered the key components that enable a gradual reorganization of the sperm plasma membrane that allows the spermatozoa to undergo an acrosome reaction and fertilize the oocyte. The aim of this work was to comprehensively examine contributors to stallion sperm capacitation by investigating bicarbonate-induced membrane remodelling steps, and elucidating the contribution of cAMP signalling to these events. In the presence of capacitating media containing bicarbonate, a significant increase in plasma membrane fluidity was readily detected using merocyanine 540 staining in the majority of viable spermatozoa within 15 min of bicarbonate exposure. Specific inhibition of soluble adenylyl cyclase (sAC) in the presence of bicarbonate by LRE1 significantly reduced the number of viable sperm with high membrane fluidity. This suggests a vital role for sAC-mediated cAMP production in the regulation of membrane fluidity. Cryo-electron tomography of viable cells with high membrane fluidity revealed a range of membrane remodelling intermediates, including destabilized membranes and zones with close apposition of the plasma membrane and the outer acrosomal membrane. However, lipidomic analysis of equivalent viable spermatozoa with high membrane fluidity demonstrated that this phenomenon was neither accompanied by a gross change in the phospholipid composition of stallion sperm membranes nor detectable sterol efflux (p > 0.05). After an early increase in membrane fluidity, a significant and cAMP-dependent increase in viable sperm with phosphatidylserine (PS), but not phosphatidylethanolamine (PE) exposure was noted. While the events observed partly resemble findings from the in vitro capacitation of sperm from other mammalian species, the lack of cholesterol removal appears to be an equine-specific phenomenon. This research will assist in the development of a defined medium for the capacitation of stallion sperm and will facilitate progress toward a functional IVF protocol for horse gametes.
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Affiliation(s)
- Paula Piccolo Maitan
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands.,Department of Veterinary Medicine, Universidade Federal de Viçosa, Viçosa, Brazil
| | - Elizabeth G Bromfield
- Department of Biomolecular Health Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands.,Priority Research Centre for Reproductive Science, The University of Newcastle, Callaghan, NSW, Australia
| | - Romy Hoogendijk
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Miguel Ricardo Leung
- Cryo-Electron Microscopy, Bijvoet Centre for Biomolecular Research, Utrecht University, Utrecht, Netherlands
| | - Tzviya Zeev-Ben-Mordehai
- Cryo-Electron Microscopy, Bijvoet Centre for Biomolecular Research, Utrecht University, Utrecht, Netherlands
| | - Chris H van de Lest
- Department of Biomolecular Health Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Jeroen W A Jansen
- Department of Biomolecular Health Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Bart Leemans
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | | | - Tom A E Stout
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Bart M Gadella
- Department of Biomolecular Health Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands.,Department of Population Health Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Heiko Henning
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
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9
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Flow-cytometric analysis of membrane integrity of stallion sperm in the face of agglutination: the "zombie sperm" dilemma. J Assist Reprod Genet 2021; 38:2465-2480. [PMID: 33991296 PMCID: PMC8490572 DOI: 10.1007/s10815-021-02134-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 02/25/2021] [Indexed: 10/31/2022] Open
Abstract
PURPOSE To define the effect of sperm agglutination, associated with incubation under capacitating conditions, on accuracy of membrane assessment via flow cytometry and to develop methods to mitigate that effect. METHODS Sperm motility was measured by CASA. Sperm were stained with PI-PSA or a novel method, LD-PSA, using fixable live/dead stain and cell dissociation treatment, before flow-cytometric analysis. Using LD-PSA, acrosome reaction and plasma membrane status were determined in equine sperm treated with 10 μm A23187 for 10 min, followed by 0, 1, or 2 h incubation in capacitating conditions. RESULTS Using PI-PSA, measured membrane integrity (MI; live sperm) was dramatically lower than was total motility (TMOT), indicating spurious results ("zombie sperm"). Sperm aggregates were largely of motile sperm. Loss of motility after A23187 treatment was associated with disaggregation and increased MI. On disaggregation using LD-PSA, MI rose, and MI then corresponded with TMOT. In equine sperm incubated after A23187 treatment, as the percentage of live acrosome-reacted sperm increased, TMOT decreased to near 0. CONCLUSION Flow cytometry assesses only individualized sperm; thus, agglutination of viable sperm alters recorded membrane integrity. As viable sperm become immotile, they individualize; therefore, factors that decrease motility, such as A23187, result in increased measured MI. Disaggregation before assessment allows more accurate determination of sperm membrane status; in this case we documented a mismatch between motility and live acrosome-reacted equine sperm that may relate to the poor repeatability of A23187 treatment for equine IVF. These findings are of profound value to future studies on sperm capacitation.
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Ortiz-Rodriguez JM, Nerozzi C, Bucci D, Mislei B, Mari G, Tamanini C, Peña FJ, Spinaci M, Galeati G. The inhibition of spermatic cystine/glutamate antiporter xCT (SLC7A11) influences the ability of cryopreserved stallion sperm to bind to heterologous zonae pellucidae. Theriogenology 2021; 167:24-31. [PMID: 33743505 DOI: 10.1016/j.theriogenology.2021.03.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 01/26/2021] [Accepted: 03/05/2021] [Indexed: 12/16/2022]
Abstract
Sperm are redox-regulated cells, and deregulation of their redox status is considered to affect male fertility and to reduce their fertilizing ability following biotechnological procedures, such as cryopreservation. Cystine (CysS), after incorporation in sperm via SLC7A11 antiporter, has been demonstrated to increase intracellular GSH content, the most important non enzymatic antioxidant. This study was aimed at investigating the role of SLC7A11 antiporter on frozen-thawed stallion sperm ability to respond to in vitro capacitating environment after post-thaw incubation with CysS and/or Sulfasalazine (SS), a specific inhibitor of SLC7A11 antiporter. Viability, motility, immunolocalization of tyrosine phosphorylated proteins and the ability to bind to heterologous zonae pellucidae were evaluated. Thawed sperm from seven stallions (2 ejaculates/stallion) was washed and resuspended in Tyrodes media; each thawed ejaculate was divided in Control (CTR) and 3 samples supplemented with: 0.5 mM Cystine (CysS), 500 μM Sulfasalazine (SS) and 0.5 mM CysS + 500 μM SS (CysS + SS). After 1 h of incubation at 37 °C, samples were washed twice, resuspended in capacitating BWW medium and incubated at 38 °C under 5% CO2. After 30 and 60 min, sperm motility, viability and tyrosine phosphorylated protein immunolocalization, used as capacitation status index, were evaluated. After 30 min of capacitation, 4 × 105 sperm were co-incubated with denuded pig oocytes in capacitation medium for 30 min for the heterologous binding assay. None of the sperm parameters studied (motility, viability and tyrosine phosphorylation) showed any difference respective to control. The number of sperm bound per oocyte (mean ± SEM) tended to increase in CysS group (44.0 ± 12.3) respect CTR (40.8 ± 10.8) while decreased in SS group (32.4 ± 7.8) (p < 0.01). Moreover, CysS + SS group showed a lower binding rate (32.0 ± 10.0) compared to CysS (p < 0.001). Our results suggest that CysS supplementation of thawed stallion sperm can influence their ability to bind to heterologous zona pellucidae as the inhibition of CysS incorporation by SLC7A11 reduced the number of sperm bound per oocyte. This effect does not seem to be ascribed to a modification of sperm motility, membrane integrity and tyrosine phosphorylation.
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Affiliation(s)
- J M Ortiz-Rodriguez
- Laboratory of Equine Reproduction and Equine Spermatology, Veterinary Teaching Hospital, University of Extremadura, Caceres, Spain
| | - C Nerozzi
- Department of Veterinary Medical Sciences (DIMEVET), University of Bologna, Bologna, Italy
| | - D Bucci
- Department of Veterinary Medical Sciences (DIMEVET), University of Bologna, Bologna, Italy
| | - B Mislei
- National Institute of Artificial Insemination (AUB-INFA), University of Bologna, Bologna, Italy
| | - G Mari
- Department of Veterinary Medical Sciences (DIMEVET), University of Bologna, Bologna, Italy; National Institute of Artificial Insemination (AUB-INFA), University of Bologna, Bologna, Italy
| | - C Tamanini
- Department of Veterinary Medical Sciences (DIMEVET), University of Bologna, Bologna, Italy
| | - F J Peña
- Laboratory of Equine Reproduction and Equine Spermatology, Veterinary Teaching Hospital, University of Extremadura, Caceres, Spain
| | - M Spinaci
- Department of Veterinary Medical Sciences (DIMEVET), University of Bologna, Bologna, Italy.
| | - G Galeati
- Department of Veterinary Medical Sciences (DIMEVET), University of Bologna, Bologna, Italy
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11
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Gibb Z, Griffin RA, Aitken RJ, De Iuliis GN. Functions and effects of reactive oxygen species in male fertility. Anim Reprod Sci 2020; 220:106456. [DOI: 10.1016/j.anireprosci.2020.106456] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 03/29/2020] [Accepted: 03/31/2020] [Indexed: 02/07/2023]
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12
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Ruiz-Díaz S, Oseguera-López I, De La Cuesta-Díaz D, García-López B, Serres C, Sanchez-Calabuig MJ, Gutiérrez-Adán A, Perez-Cerezales S. The Presence of D-Penicillamine during the In Vitro Capacitation of Stallion Spermatozoa Prolongs Hyperactive-Like Motility and Allows for Sperm Selection by Thermotaxis. Animals (Basel) 2020; 10:ani10091467. [PMID: 32825582 PMCID: PMC7552178 DOI: 10.3390/ani10091467] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 08/12/2020] [Accepted: 08/18/2020] [Indexed: 12/20/2022] Open
Abstract
Assisted reproductive technologies (ARTs) in the horse still yield suboptimal results in terms of pregnancy rates. One of the reasons for this is the lack of optimal conditions for the sperm capacitation in vitro. This study assesses the use of synthetic human tubal fluid (HTF) supplemented with D-penicillamine (HTF + PEN) for the in vitro capacitation of frozen/thawed stallion spermatozoa by examining capacitation-related events over 180 min of incubation. Besides these events, we explored the in vitro capacity of the spermatozoa to migrate by thermotaxis and give rise to a population of high-quality spermatozoa. We found that HTF induced higher levels of hyperactive-like motility and protein tyrosine phosphorylation (PTP) compared to the use of a medium commonly used in this species (Whitten's). Also, HTF + PEN was able to maintain this hyperactive-like motility, otherwise lost in the absence of PEN, for 180 min, and also allowed for sperm selection by thermotaxis in vitro. Remarkably, the selected fraction was enriched in spermatozoa showing PTP along the whole flagellum and lower levels of DNA fragmentation when compared to the unselected fraction (38% ± 11% vs 4.4% ± 1.1% and 4.2% ± 0.4% vs 11% ± 2% respectively, t-test p < 0.003, n = 6). This procedure of in vitro capacitation of frozen/thawed stallion spermatozoa in HTF + PEN followed by in vitro sperm selection by thermotaxis represents a promising sperm preparation strategy for in vitro fertilization and intracytoplasmic sperm injection in this species.
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Affiliation(s)
- Sara Ruiz-Díaz
- Department of Animal Reproduction, National Institute for Agriculture and Food Research and Technology (INIA), 28040 Madrid, Spain; (S.R.-D.); (D.D.L.C.-D.); (B.G.-L.); (S.P.-C.)
- Mistral Fertility Clinics S.L., Clínica Tambre, 28002 Madrid, Spain
| | - Ivan Oseguera-López
- Unidad Iztapalapa, Universidad Autónoma Metropolitana, Ciudad de México 09340, Mexico;
| | - David De La Cuesta-Díaz
- Department of Animal Reproduction, National Institute for Agriculture and Food Research and Technology (INIA), 28040 Madrid, Spain; (S.R.-D.); (D.D.L.C.-D.); (B.G.-L.); (S.P.-C.)
| | - Belén García-López
- Department of Animal Reproduction, National Institute for Agriculture and Food Research and Technology (INIA), 28040 Madrid, Spain; (S.R.-D.); (D.D.L.C.-D.); (B.G.-L.); (S.P.-C.)
| | - Consuelo Serres
- Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, Universidad Complutense de Madrid (UCM), 28040 Madrid, Spain; (C.S.); (M.J.S.-C.)
| | - Maria José Sanchez-Calabuig
- Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, Universidad Complutense de Madrid (UCM), 28040 Madrid, Spain; (C.S.); (M.J.S.-C.)
| | - Alfonso Gutiérrez-Adán
- Department of Animal Reproduction, National Institute for Agriculture and Food Research and Technology (INIA), 28040 Madrid, Spain; (S.R.-D.); (D.D.L.C.-D.); (B.G.-L.); (S.P.-C.)
- Correspondence:
| | - Serafin Perez-Cerezales
- Department of Animal Reproduction, National Institute for Agriculture and Food Research and Technology (INIA), 28040 Madrid, Spain; (S.R.-D.); (D.D.L.C.-D.); (B.G.-L.); (S.P.-C.)
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13
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Effect of MnTBAP on in vitro capacitation of frozen-thawed stallion sperm. Anim Reprod Sci 2020; 221:106570. [PMID: 32861120 DOI: 10.1016/j.anireprosci.2020.106570] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 07/29/2020] [Accepted: 07/30/2020] [Indexed: 12/24/2022]
Abstract
In vitro manipulation of spermatozoa leads to deleterious changes of structure and function that occur mainly due to oxidative stress, therefore, prevention or treatment is a strategy to improve the functions of processed sperm. In the present study, the aim was to evaluate the effects of MnTBAP supplementation, a compound with antioxidant activity, on in vitro capacitation conditions of thawed equine sperm. For this purpose, stallion spermatozoa (2 × 106 cells/mL) were incubated in the sperm-TLP base medium for 4 h in which there were three different conditions: non-capacitating, capacitating, and capacitating plus 150 mM MnTBAP. There were incubations for 4 h at 37.5 °C in a humidified air atmosphere. Sample analysis was performed immediately after thawing (0 h), and at the end of the incubation period (4 h), unless otherwise indicated. The following variables were evaluated for spermatozoa: plasma membrane integrity and fluidity, acrosome integrity, intracellular calcium concentrations, intracellular pH, tyrosine phosphorylation, ATP concentrations, motility and heterologous zona-binding assay, using flow cytometry, fluorescent microscopy and/or chemiluminescence, depending on the most appropriate procedure for the variable being evaluated. Results indicated that capacitation-like changes were synergistically induced by the cAMP agonists, phosphodiesterase inhibitor and bicarbonate. The presence of bovine serum albumin was harmful to the plasma membrane. The MnTBAP supplementation had a positive effect on viability-related markers (plasma membrane integrity, membrane fluidity, associated with greater intracellular pH) when there were capacitating conditions. In conclusion, the activity of MnTBAP contributes to improving the in vitro incubation conditions of frozen-thawed stallion sperm.
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14
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Leemans B, Stout TAE, De Schauwer C, Heras S, Nelis H, Hoogewijs M, Van Soom A, Gadella BM. Update on mammalian sperm capacitation: how much does the horse differ from other species? Reproduction 2020; 157:R181-R197. [PMID: 30721132 DOI: 10.1530/rep-18-0541] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 02/04/2019] [Indexed: 12/21/2022]
Abstract
In contrast to various other mammalian species, conventional in vitro fertilization (IVF) with horse gametes is not reliably successful. In particular, stallion spermatozoa fails to penetrate the zona pellucida, most likely due to incomplete activation of stallion spermatozoa (capacitation) under in vitro conditions. In other mammalian species, specific capacitation triggers have been described; unfortunately, none of these is able to induce full capacitation in stallion spermatozoa. Nevertheless, knowledge of capacitation pathways and their molecular triggers might improve our understanding of capacitation-related events observed in stallion sperm. When sperm cells are exposed to appropriate capacitation triggers, several molecular and biochemical changes should be induced in the sperm plasma membrane and cytoplasm. At the level of the sperm plasma membrane, (1) an increase in membrane fluidity, (2) cholesterol depletion and (3) lipid raft aggregation should occur consecutively; the cytoplasmic changes consist of protein tyrosine phosphorylation and elevated pH, cAMP and Ca2+ concentrations. These capacitation-related events enable the switch from progressive to hyperactivated motility of the sperm cells, and the induction of the acrosome reaction. These final capacitation triggers are indispensable for sperm cells to migrate through the viscous oviductal environment, penetrate the cumulus cells and zona pellucida and, finally, fuse with the oolemma. This review will focus on molecular aspects of sperm capacitation and known triggers in various mammalian species. Similarities and differences with the horse will be highlighted to improve our understanding of equine sperm capacitation/fertilizing events.
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Affiliation(s)
- Bart Leemans
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Tom A E Stout
- Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.,Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Catharina De Schauwer
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Sonia Heras
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Hilde Nelis
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Maarten Hoogewijs
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Ann Van Soom
- Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Bart M Gadella
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.,Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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15
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Contreras MJ, Treulen F, Arias ME, Silva M, Fuentes F, Cabrera P, Felmer R. Cryopreservation of stallion semen: Effect of adding antioxidants to the freezing medium on sperm physiology. Reprod Domest Anim 2020; 55:229-239. [PMID: 31868975 DOI: 10.1111/rda.13611] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Accepted: 12/19/2019] [Indexed: 11/28/2022]
Abstract
Cryopreservation of stallion semen has not reached the level of efficiency and positive results described in other species. This is mainly due to the greater sensitivity of stallion sperm to the freezing process, showing higher rates of oxidative stress and plasma membrane damage, which trigger the activation of several cell damage pathways that ultimately culminate in DNA fragmentation and cell death. Therefore, finding molecules that improve the efficiency of this technique in stallion by preventing oxidative stress and cell damage is required. Thus, the aim of the present study was to evaluate the effect of adding three antioxidants (MnTBAP, NAC and FeTPPS) to the freezing medium on the quality and functional parameters of stallion sperm. Semen samples from three stallions frozen with the antioxidants were evaluated in two conditions: (a) adding the antioxidants before freezing, and (b) before and after freezing. Plasma membrane integrity, mitochondrial membrane potential, lipid peroxidation, intracellular ROS levels, membrane lipid disorder, DNA damage, sperm motility and binding to the zona pellucida were assessed. The results showed that MnTBAP was the antioxidant treatment that best controlled the oxidative stress process and post-thaw cell damage, showing higher plasma membrane integrity, mitochondrial membrane potential, sperm motility, number of spermatozoa bound to the zona pellucida of bovine oocytes and lower lipid disorder. Additionally, it was determined that a second post-thaw application of antioxidants is detrimental since induced higher cell damage and lower sperm motility, without showing any beneficial effect on the spermatozoa.
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Affiliation(s)
- María José Contreras
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera, Temuco, Chile
| | - Favián Treulen
- Escuela de Tecnología Médica, Facultad de Ciencias, Universidad Mayor, Temuco, Chile
| | - María Elena Arias
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera, Temuco, Chile.,Department of Animal Production, Faculty of Agriculture and Forestry Sciences, Universidad de La Frontera, Temuco, Chile
| | - Mauricio Silva
- Department of Veterinary Sciences and Public Health, Universidad Católica de Temuco, Temuco, Chile
| | - Fernanda Fuentes
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera, Temuco, Chile
| | - Paulina Cabrera
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera, Temuco, Chile
| | - Ricardo Felmer
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera, Temuco, Chile.,Department of Agricultural Sciences and Natural Resources, Faculty of Agriculture and Forestry Sciences, Universidad de La Frontera, Temuco, Chile
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16
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Salimi H, Johnson J, Flores MG, Zhang MS, O'Malley Y, Houtman JC, Schlievert PM, Haim H. The lipid membrane of HIV-1 stabilizes the viral envelope glycoproteins and modulates their sensitivity to antibody neutralization. J Biol Chem 2019; 295:348-362. [PMID: 31757809 DOI: 10.1074/jbc.ra119.009481] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 11/19/2019] [Indexed: 11/06/2022] Open
Abstract
The envelope glycoproteins (Envs) of HIV-1 are embedded in the cholesterol-rich lipid membrane of the virus. Chemical depletion of cholesterol from HIV-1 particles inactivates their infectivity. We observed that diverse HIV-1 strains exhibit a range of sensitivities to such treatment. Differences in sensitivity to cholesterol depletion could not be explained by variation in Env components known to interact with cholesterol, including the cholesterol-recognition motif and cytoplasmic tail of gp41. Using antibody-binding assays, measurements of virus infectivity, and analyses of lipid membrane order, we found that depletion of cholesterol from HIV-1 particles decreases the conformational stability of Env. It enhances exposure of partially cryptic epitopes on the trimer and increases sensitivity to structure-perturbing treatments such as antibodies and cold denaturation. Substitutions in the cholesterol-interacting motif of gp41 induced similar effects as depletion of cholesterol. Surface-acting agents, which are incorporated into the virus lipid membrane, caused similar effects as disruption of the Env-cholesterol interaction. Furthermore, substitutions in gp120 that increased structural stability of Env (i.e. induced a "closed" conformation of the trimer) increased virus resistance to cholesterol depletion and to the surface-acting agents. Collectively, these results indicate a critical contribution of the viral membrane to the stability of the Env trimer and to neutralization resistance against antibodies. Our findings suggest that the potency of poorly neutralizing antibodies, which are commonly elicited in vaccinated individuals, may be markedly enhanced by altering the lipid composition of the viral membrane.
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Affiliation(s)
- Hamid Salimi
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Jacklyn Johnson
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Manuel G Flores
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Michael S Zhang
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Yunxia O'Malley
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Jon C Houtman
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Patrick M Schlievert
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Hillel Haim
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242.
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17
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Zhu Z, Li R, Wang L, Zheng Y, Hoque SAM, Lv Y, Zeng W. Glycogen Synthase Kinase-3 Regulates Sperm Motility and Acrosome Reaction via Affecting Energy Metabolism in Goats. Front Physiol 2019; 10:968. [PMID: 31417426 PMCID: PMC6682598 DOI: 10.3389/fphys.2019.00968] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 07/11/2019] [Indexed: 12/13/2022] Open
Abstract
Hyperactivation and acrosome reaction of sperm are pre-requisite steps for fertilization. However, the hyperactivation and acrosome reaction are critically controlled through the phosphorylation of specific proteins. Glycogen synthase kinase-3 (GSK3), a serine/threonine kinase with two different isoforms (α and β), is involved in biochemical signaling pathways. This study was aimed to investigate whether the GSK3α/β is present in goat sperm and its regulatory role in sperm motility and acrosome reaction. GSK3α/β was detected with immunofluorescence and Western blotting. Sperm motility, membrane integrity, acrosome reaction, mitochondrial membrane potential, phospho-Ser21-GSK3α and phospho-Ser9-GSK3β were analyzed. The ATP production and activities of lactate dehydrogenase (LDH), malate dehydrogenase (MDH), and succinate dehydrogenase (SDH) were measured. It was observed that the GSK3α/β was expressed in goat sperm, especially in the peri-acrosomal, mid-piece and principal piece of the tail. The abundance of GSK3α/β in sperm was increased during transit along the epididymis. Addition of either 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) or CHIR99021 significantly increased the sperm motility patterns and GSK3α/β phosphorylation. Interestingly, the adenosine triphosphate (ATP) production, activities of LDH, MDH and SDH were observed to be increased in the CHIR99021 treatment. The results suggested that GSK3α/β regulates sperm motility and acrosome reaction via phospho-ser21-GSK3α and phospho-ser9-GSK3β that involved in the regulation of sperm energy metabolism.
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Affiliation(s)
- Zhendong Zhu
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, China
| | - Rongnan Li
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, China
| | - Liqiang Wang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, China
| | - Yi Zheng
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, China
| | - S A Masudul Hoque
- Department of Animal Breeding and Genetics, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - Yinghua Lv
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, China.,College of Chemistry & Pharmacy, Northwest A&F University, Yangling, China
| | - Wenxian Zeng
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, China
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18
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BODIPY-cholesterol can be reliably used to monitor cholesterol efflux from capacitating mammalian spermatozoa. Sci Rep 2019; 9:9804. [PMID: 31285440 PMCID: PMC6614389 DOI: 10.1038/s41598-019-45831-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 06/11/2019] [Indexed: 02/06/2023] Open
Abstract
Capacitation is the final maturation step spermatozoa undergo prior to fertilisation. The efflux of cholesterol from the sperm membrane to the extracellular environment is a crucial step during capacitation but current methods to quantify this process are suboptimal. In this study, we validate the use of a BODIPY-cholesterol assay to quantify cholesterol efflux from spermatozoa during in vitro capacitation, using the boar as a model species. The novel flow cytometric BODIPY-cholesterol assay was validated with endogenous cholesterol loss as measured by mass spectrometry and compared to filipin labelling. Following exposure to a range of conditions, the BODIPY-cholesterol assay was able to detect and quantify cholesterol efflux akin to that measured with mass spectrometry. The ability to counterstain for viability is a unique feature of this assay that allowed us to highlight the importance of isolating viable cells only for a reliable measure of cholesterol efflux. Finally, the BODIPY-cholesterol assay proved to be the superior method to quantify cholesterol efflux relative to filipin labelling, though filipin remains useful for assessing cholesterol redistribution. Taken together, the BODIPY-cholesterol assay is a simple, inexpensive and reliable flow cytometric method for the measurement of cholesterol efflux from spermatozoa during in vitro capacitation.
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19
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Bernecic NC, Gadella BM, Leahy T, de Graaf SP. Novel methods to detect capacitation-related changes in spermatozoa. Theriogenology 2019; 137:56-66. [PMID: 31230703 DOI: 10.1016/j.theriogenology.2019.05.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Prior to interaction with the oocyte, spermatozoa must undergo capacitation, which involves a series of physio-chemical transformations that occur in the female tract. As capacitation is a pre-requisite for successful fertilisation, it is a topic of great interest for sperm biologists, but the complexity of the numerous biochemical and biophysical processes involved make it difficult to measure. Capacitation is an extremely complex event that encompasses numerous integrated processes that can occur concurrently during this window of time. The identification of techniques to accurately assess and quantify capacitation is therefore crucial to gain a meaningful insight into this fascinating sperm maturation event. Whilst there are extensive reviews in the literature that focus on the functional changes to spermatozoa during capacitation, few have examined the methods required to measure these changes. The aim of this review is to highlight frequently used methods to quantify different stages of capacitation and identify promising novel techniques. Factors that are able to modulate various capacitation processes will also be discussed. The overall outcome is to provide researchers with a toolbox of methods that can be used to gain a deeper understanding of the intricacies of capacitation in spermatozoa.
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Affiliation(s)
- Naomi C Bernecic
- The University of Sydney, Faculty of Science, NSW, 2006, Australia.
| | - Bart M Gadella
- Department of Biochemistry & Cell Biology, Utrecht University, the Netherlands; Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, the Netherlands
| | - Tamara Leahy
- The University of Sydney, Faculty of Science, NSW, 2006, Australia
| | - Simon P de Graaf
- The University of Sydney, Faculty of Science, NSW, 2006, Australia
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20
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Rota A, Sabatini C, Przybył A, Ciaramelli A, Panzani D, Camillo F. Post-thaw Addition of Caffeine and/or Pentoxifylline Affect Differently Motility of Horse and Donkey-Cryopreserved Spermatozoa. J Equine Vet Sci 2019; 75:41-47. [PMID: 31002091 DOI: 10.1016/j.jevs.2019.01.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 01/08/2019] [Accepted: 01/11/2019] [Indexed: 10/27/2022]
Abstract
To increase sperm motility, several molecules have been tested in mammals. Methylxanthines have shown effects on sperm motility, capacitation, and on in vitro fertilization processes. The aim of the study was to evaluate if the post-thaw addition of caffeine and/or pentoxifylline changes motility parameters of cryopreserved stallion and donkey spermatozoa. Straws derived from 14 horses and 7 donkeys were thawed and diluted in a milk-based extender to obtain the following final concentrations: CTR (control, no additives), CAF 5 (5 mM caffeine), CAF 10 (10 mM caffeine), PTX 5 (5 mM pentoxifylline), PTX 10 (10 mM pentoxifylline), CAF-PTX (5 mM caffeine and 5 mM pentoxifylline). Samples were evaluated immediately post-thaw and after 60 and 120 minutes of incubation at 37°C. In horses, overall total motility was significantly lower in CTR than in to CAF5, CAF-PTX, PTX5, PTX10, whereas progressive motility increased only in CAF5 and PTX5 (P < .05). No differences between control and treatments were seen for donkey semen. In CTR, during the first hour of incubation horses' sperm cells showed a larger decrease than donkeys' ones in all parameters (P < .05), except for lateral sperm head displacement. Thus, post-thaw motility and velocity decreased more sharply in horses than in donkeys. Caffeine and pentoxifylline-added post-thaw were able to increase the proportion of motile spermatozoa only for stallions and not for donkeys. Whether the improvement in post-thaw motility of equine spermatozoa may have an effect on in vivo or in vitro pregnancy rates remains to be determined.
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Affiliation(s)
- Alessandra Rota
- Dipartimento di Scienze Veterinarie, Università di Pisa, Pisa, Italy.
| | - Chiara Sabatini
- Dipartimento di Scienze Veterinarie, Università di Pisa, Pisa, Italy
| | | | | | - Duccio Panzani
- Dipartimento di Scienze Veterinarie, Università di Pisa, Pisa, Italy
| | - Francesco Camillo
- Dipartimento di Scienze Veterinarie, Università di Pisa, Pisa, Italy
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21
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Swegen A, Smith ND, Gibb Z, Curry BJ, Aitken RJ. The serine protease testisin is present on the surface of capacitated stallion spermatozoa and interacts with key zona pellucida binding proteins. Andrology 2018; 7:199-212. [PMID: 30549223 DOI: 10.1111/andr.12569] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 10/28/2018] [Accepted: 11/03/2018] [Indexed: 01/06/2023]
Abstract
BACKGROUND AND OBJECTIVES Serine proteases are emerging as important players in the spermatozoon's acquisition of functional competence. This study aimed to characterize the serine protease testisin (PRSS21) in stallion spermatozoa, examining its surface expression, possible origins in the testis and epididymis, and changes in response to capacitation and acrosome reaction, as well as its capacity to form high molecular weight complexes and interact with other proteins. MATERIALS AND METHODS The role of serine proteases in spontaneous capacitation and acrosome reaction of stallion spermatozoa was established using the serine protease inhibitor, AEBSF. Testisin localization, before and after exposure of stallion spermatozoa to capacitating conditions and calcium ionophore, was examined using live cell immunofluorescence and flow cytometry. Immunohistochemistry of testicular and epididymal tissues was used to further dissect the origins of sperm testisin. Testisin's participation in high molecular weight protein complexes and identification of its interacting partner proteins were investigated using Blue Native PAGE, co-immunoprecipitation, and mass spectrometry, with interrogation of protein-protein interaction databases and gene ontology analysis of partner proteins used to further explore the potential roles of the testisin-containing complex in sperm function. RESULTS Testisin surface expression increased significantly in capacitated spermatozoa (p < 0.001), increased further following acrosome reaction (p < 0.01), and was localized to the equatorial region of the sperm head. Testisin was also detected in luminal fluid within the caput and corpus regions of the epididymis, epididymal spermatozoa, and epididymal epithelial cells. Testisin formed several multiprotein complexes; co-immunoprecipitation revealed interactions of testisin with a multitude of zona pellucida-binding proteins, including ZPBP, ZAN, acrosin, several heat-shock proteins, and components of the TCP1 complex. CONCLUSION Testisin appears to form part of the zona pellucida-binding complex in stallion spermatozoa and may be involved in the proteolytic cascade that prepares the sperm surface for interaction with the oocyte.
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Affiliation(s)
- A Swegen
- Priority Research Centre for Reproductive Science, University of Newcastle, Callaghan, NSW, Australia
| | - N D Smith
- Analytical and Biomolecular Research Facility, University of Newcastle, Callaghan, NSW, Australia
| | - Z Gibb
- Priority Research Centre for Reproductive Science, University of Newcastle, Callaghan, NSW, Australia
| | - B J Curry
- Priority Research Centre for Reproductive Science, University of Newcastle, Callaghan, NSW, Australia
| | - R J Aitken
- Priority Research Centre for Reproductive Science, University of Newcastle, Callaghan, NSW, Australia
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22
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Arroyo-Salvo C, Sanhueza F, Fuentes F, Treulén F, Arias ME, Cabrera P, Silva M, Felmer R. Effect of human tubal fluid medium and hyperactivation inducers on stallion sperm capacitation and hyperactivation. Reprod Domest Anim 2018; 54:184-194. [DOI: 10.1111/rda.13328] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 08/22/2018] [Indexed: 12/30/2022]
Affiliation(s)
- Camila Arroyo-Salvo
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN); Universidad de La Frontera; Temuco Chile
| | - Francisco Sanhueza
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN); Universidad de La Frontera; Temuco Chile
| | - Fernanda Fuentes
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN); Universidad de La Frontera; Temuco Chile
| | - Favián Treulén
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN); Universidad de La Frontera; Temuco Chile
- School of Medical Technology, Faculty of Sciences; Universidad Mayor; Temuco Chile
| | - María Elena Arias
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN); Universidad de La Frontera; Temuco Chile
- Department of Animal Production, Faculty of Agriculture and Forestry Sciences; Universidad de La Frontera; Temuco Chile
| | - Paulina Cabrera
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN); Universidad de La Frontera; Temuco Chile
| | - Mauricio Silva
- Department of Veterinary Sciences and Public Health; Universidad Católica de Temuco; Temuco Chile
| | - Ricardo Felmer
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN); Universidad de La Frontera; Temuco Chile
- Department of Agricultural Sciences and Natural Resources, Faculty of Agriculture and Forestry Sciences; Universidad de La Frontera; Temuco Chile
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23
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Dominguez EM, Moreno-Irusta A, Guidobaldi HA, Tribulo H, Giojalas LC. Improved bovine in vitro embryo production with sexed and unsexed sperm selected by chemotaxis. Theriogenology 2018; 122:1-8. [PMID: 30199739 DOI: 10.1016/j.theriogenology.2018.08.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 08/24/2018] [Accepted: 08/26/2018] [Indexed: 10/28/2022]
Abstract
Assisted reproductive techniques (ART) have been widely used in farm animals in the last decades. Sexed cryopreserved spermatozoa, ovum pick up, in vitro embryo production and transfer constitute the ART that have revolutionized the dairy industry. However, the efficiency of some of these techniques is still low due in part to sperm quality, which influences fertilization, embryo development and implantation. The Sperm Selection Assay (SSA), based on sperm chemotaxis towards progesterone, provides a sperm subpopulation enriched with spermatozoa that are capacitated, with intact DNA and low level of oxidative stress. Since the SSA selects a sperm subpopulation at optimum physiological state, the application of the SSA may improve the efficiency of the current ART. The aim of this study was to adapt the SSA for unsexed and sexed bovine frozen-thawed semen samples, and then to test whether sperm selection by the SSA improves the cleavage rate of bovine embryos in vitro. The optimal SSA conditions to obtain the higher sperm accumulation percentage given by chemotaxis were the same for both unsexed and sexed semen samples. Thus, sperm accumulation in W2 was significantly higher when: 2 million sperm per mL were placed in W1 (unsexed samples: 12 ± 1%, p = 0.002; sexed samples: 14 ± 3%, p = 0.02); 1 pM progesterone was placed in W2 (unsexed sample: 9 ± 1%, p = 0.009; sexed samples: 11 ± 2%, p = 0.02); and to incubate the SSA device for 10 min (unsexed samples: 17 ± 2%, p = 0.007; sexed samples: 10 ± 1%, p = 0.004). We found that the quality of spermatozoa recovered from W2 in unsexed and sexed semen was enhanced. Thus, the capacitation index was significantly increased (unsexed samples: 1.75 ± 0.1, p = 0.0001; sexed samples: 1.76 ± 0.2, p = 0.004), while DNA fragmentation index was significantly decreased (unsexed samples: 0.33 ± 0.07, p = 0.0003; sexed samples: 0.32 ± 0.04, p = 0.002). Moreover, the cleavage index of oocytes fertilized with either unsexed or sexed SSA-selected sperm was significantly improved (unsexed samples: 3.2 ± 0.4, p = 0.0001; sexed samples: 2.3 ± 0.33, p = 0.03). Thus, we show that the SSA can be used to recruit a bovine sperm subpopulation at optimal functional state regardless of whether the sample is previously sexed, and that this optimal state improves bovine embryo cleavage rate.
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Affiliation(s)
- Esteban Mauricio Dominguez
- Centro de Biologia Celular y Molecular, Facultad de Ciencias Exactas, Fisicas y Naturales (FCEFN), Universidad Nacional de Córdoba (UNC), Córdoba, Argentina; Instituto de Investigaciones Biologicas y Tecnologicas, Consejo de Investigaciones Científicas y Técnicas (CONICET), UNC-FCEFN, Córdoba, Argentina
| | - Ayelen Moreno-Irusta
- Centro de Biologia Celular y Molecular, Facultad de Ciencias Exactas, Fisicas y Naturales (FCEFN), Universidad Nacional de Córdoba (UNC), Córdoba, Argentina; Instituto de Investigaciones Biologicas y Tecnologicas, Consejo de Investigaciones Científicas y Técnicas (CONICET), UNC-FCEFN, Córdoba, Argentina
| | - Héctor Alejandro Guidobaldi
- Centro de Biologia Celular y Molecular, Facultad de Ciencias Exactas, Fisicas y Naturales (FCEFN), Universidad Nacional de Córdoba (UNC), Córdoba, Argentina; Instituto de Investigaciones Biologicas y Tecnologicas, Consejo de Investigaciones Científicas y Técnicas (CONICET), UNC-FCEFN, Córdoba, Argentina
| | - Huberto Tribulo
- Instituto de Reproducción Animal Córdoba, Estación Gral. Paz, Paraje Pozo del Tigre, Córdoba, Argentina
| | - Laura Cecilia Giojalas
- Centro de Biologia Celular y Molecular, Facultad de Ciencias Exactas, Fisicas y Naturales (FCEFN), Universidad Nacional de Córdoba (UNC), Córdoba, Argentina; Instituto de Investigaciones Biologicas y Tecnologicas, Consejo de Investigaciones Científicas y Técnicas (CONICET), UNC-FCEFN, Córdoba, Argentina.
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24
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First Publication to Describe a Protocol for the Liquid Storage of Stallion Spermatozoa for 7 Days. J Equine Vet Sci 2018. [DOI: 10.1016/j.jevs.2018.05.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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25
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Cysteine protects rabbit spermatozoa against reactive oxygen species-induced damages. PLoS One 2017; 12:e0181110. [PMID: 28700739 PMCID: PMC5507327 DOI: 10.1371/journal.pone.0181110] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Accepted: 06/25/2017] [Indexed: 11/24/2022] Open
Abstract
The process of cryopreservation results in over-production of reactive oxygen species, which is extremely detrimental to spermatozoa. The aim of this study was to investigate whether addition of cysteine to freezing extender would facilitate the cryosurvival of rabbit spermatozoa, and if so, how cysteine protects spermatozoa from cryodamages. Freshly ejaculated semen was diluted with Tris-citrate-glucose extender supplemented with different concentrations of cysteine. The motility, intact acrosomes, membrane integrity, mitochondrial potentials, 8-hydroxyguanosine level and sperm-zona pellucida binding capacity were examined. Furthermore, glutathione peroxidase (GPx) activity, glutathione content (GSH), and level of reactive oxygen species (ROS) and hydrogen peroxide of spermatozoa were analyzed. The values of motility, intact acrosomes, membrane integrity, mitochondrial potentials and sperm-zona pellucida binding capacity of the frozen-thawed spermatozoa in the treatment of cysteine were significantly higher than those of the control. Addition of cysteine to extenders improved the GPx activity and GSH content of spermatozoa, while lowered the ROS, DNA oxidative alterations and lipid peroxidation level, which makes spermatozoa avoid ROS to attack DNA, the plasma membrane and mitochondria. In conclusion, cysteine protects spermatozoa against ROS-induced damages during cryopreservation and post-thaw incubation. Addition of cysteine is recommended to facilitate the improvement of semen preservation for the rabbit breeding industry.
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26
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Águila L, Zambrano F, Arias ME, Felmer R. Sperm capacitation pretreatment positively impacts bovine intracytoplasmic sperm injection. Mol Reprod Dev 2017; 84:649-659. [PMID: 28513911 DOI: 10.1002/mrd.22834] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 05/02/2017] [Accepted: 05/11/2017] [Indexed: 11/08/2022]
Abstract
The efficiency of intracytoplasmic sperm injection (ICSI) in bovines is low compared to other species due in part to inadequate egg activation and sperm nucleus decondensation after injection. We hypothesized that this low efficiency is due to the lack of complete sperm capacitation, so we evaluated the effects of isobutylmethylxanthine (IBMX) and methyl-β-cyclodextrin (MβCD) on bovine sperm capacitation and on the preimplantation developmental potential of bovine embryos generated by ICSI. Treatment with IBMX and MβCD decreased sperm viability (between 13-30%); nevertheless, 0.4 mM IBMX and 1 mM MβCD increased (p < 0.05) capacitation metrics-that is, acrosome exocytosis, intracellular calcium level, plasma membrane fluidity, and tyrosine phosphorylation-compared to the control. After ICSI, embryos injected with IBMX- and MβCD-treated sperm showed similar cleavage to the untreated group (range 82-88%). Pronucleus formation rate was higher with MβCD-pretreatment (54%) compared to the control group (25%), and blastocyst rate was significantly improved with MβCD-pretreatment (24%) compared to the IBMX (18%) and control (17%) groups. Importantly, embryo quality-as assessed by the total number of cells, cell allocation, and apoptotic cell index-was not affected by the sperm treatments. In conclusion, MβCD pretreatment of sperm improved the efficiency of blastocyst production in bovine ICSI.
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Affiliation(s)
- Luis Águila
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera, Temuco, Chile
| | - Fabiola Zambrano
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera, Temuco, Chile
| | - Maria E Arias
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera, Temuco, Chile.,Faculty of Agriculture and Forestry Sciences, Department of Agricultural Sciences and Natural Resources, Universidad de La Frontera, Temuco, Chile
| | - Ricardo Felmer
- Laboratory of Reproduction, Centre of Reproductive Biotechnology (CEBIOR-BIOREN), Universidad de La Frontera, Temuco, Chile.,Faculty of Agriculture and Forestry Sciences, Department of Agricultural Sciences and Natural Resources, Universidad de La Frontera, Temuco, Chile
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27
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Sperm-bound antisperm antibodies prevent capacitation of bovine spermatozoa. Theriogenology 2017; 89:58-67. [DOI: 10.1016/j.theriogenology.2016.10.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 10/10/2016] [Accepted: 10/10/2016] [Indexed: 11/19/2022]
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28
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Yoshimoto H, Takeo T, Irie T, Nakagata N. Fertility of cold-stored mouse sperm is recovered by promoting acrosome reaction and hyperactivation after cholesterol efflux by methyl-beta-cyclodextrin. Biol Reprod 2017; 96:446-455. [DOI: 10.1095/biolreprod.116.142901] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 12/24/2016] [Accepted: 01/04/2017] [Indexed: 12/17/2022] Open
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29
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Macías-García B, Rocha A, González-Fernández L. Extracellular calcium regulates protein tyrosine phosphorylation through calcium-sensing receptor (CaSR) in stallion sperm. Mol Reprod Dev 2016; 83:236-45. [DOI: 10.1002/mrd.22615] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 01/11/2016] [Indexed: 12/27/2022]
Affiliation(s)
- Beatriz Macías-García
- CECA/ICETA: Centro de Estudos de Ciência Animal/Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto; University of Porto; Portugal
- ICBAS: Instituto de Ciências Biomédicas Abel Salazar; University of Porto; Portugal
| | - Antonio Rocha
- CECA/ICETA: Centro de Estudos de Ciência Animal/Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto; University of Porto; Portugal
- ICBAS: Instituto de Ciências Biomédicas Abel Salazar; University of Porto; Portugal
| | - Lauro González-Fernández
- CECA/ICETA: Centro de Estudos de Ciência Animal/Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto; University of Porto; Portugal
- ICBAS: Instituto de Ciências Biomédicas Abel Salazar; University of Porto; Portugal
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30
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Leahy T, Rickard JP, Aitken RJ, de Graaf SP. Penicillamine prevents ram sperm agglutination in media that support capacitation. Reproduction 2016; 151:167-77. [DOI: 10.1530/rep-15-0413] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Ram spermatozoa are difficult to capacitate in vitro. Here we describe a further complication, the unreported phenomenon of head-to-head agglutination of ram spermatozoa following dilution in the capacitation medium Tyrodes plus albumin, lactate and pyruvate (TALP). Sperm agglutination is immediate, specific and persistent and is not associated with a loss of motility. Agglutination impedes in vitro sperm handling and analysis. So the objectives of this study were to investigate the cause of sperm agglutination and potential agents which may reduce agglutination. The percentage of non-agglutinated, motile spermatozoa increased when bicarbonate was omitted from complete TALP suggesting that bicarbonate ions stimulate the agglutination process. d-penicillamine (PEN), a nucleophilic thiol, was highly effective at reducing agglutination. The inclusion of 250 μM PEN in TALP reduced the incidence of motile, agglutinated spermatozoa from 76.7±2.7% to 2.8±1.4%. It was then assessed if PEN (1 mM) could be included in existing ram sperm capacitation protocols (TALP +1 mM dibutyryl cAMP, caffeine and theophylline) to produce spermatozoa that were simultaneously capacitated and non-agglutinated. This protocol resulted in a sperm population which displayed high levels of tyrosine phosphorylated proteins and lipid disordered membranes (merocyanine-540) while remaining motile, viable, acrosome-intact and non-agglutinated. In summary, PEN (1 mM) can be included in ram sperm capacitation protocols to reduce sperm agglutination and allow for the in vitro assessment of ram sperm capacitation.
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31
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Bromfield EG, McLaughlin EA, Aitken RJ, Nixon B. Heat Shock Protein member A2 forms a stable complex with angiotensin converting enzyme and protein disulfide isomerase A6 in human spermatozoa. Mol Hum Reprod 2015; 22:93-109. [DOI: 10.1093/molehr/gav073] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 12/03/2015] [Indexed: 12/18/2022] Open
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32
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Effect of different media additives on capacitation of frozen–thawed ram spermatozoa as a potential replacement for estrous sheep serum. Theriogenology 2015; 84:948-55. [DOI: 10.1016/j.theriogenology.2015.05.032] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 05/22/2015] [Accepted: 05/29/2015] [Indexed: 11/21/2022]
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33
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Águila L, Arias ME, Vargas T, Zambrano F, Felmer R. Methyl-β-Cyclodextrin Improves Sperm Capacitation Status Assessed by Flow Cytometry Analysis and Zona Pellucida-Binding Ability of Frozen/Thawed Bovine Spermatozoa. Reprod Domest Anim 2015; 50:931-8. [DOI: 10.1111/rda.12611] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 08/20/2015] [Indexed: 11/28/2022]
Affiliation(s)
- L Águila
- Laboratory of Reproduction; Centre of Reproductive Biotechnology (CEBIOR-BIOREN); Universidad de La Frontera; Temuco Chile
| | - ME Arias
- Laboratory of Reproduction; Centre of Reproductive Biotechnology (CEBIOR-BIOREN); Universidad de La Frontera; Temuco Chile
| | - T Vargas
- Laboratory of Reproduction; Centre of Reproductive Biotechnology (CEBIOR-BIOREN); Universidad de La Frontera; Temuco Chile
| | - F Zambrano
- Laboratory of Reproduction; Centre of Reproductive Biotechnology (CEBIOR-BIOREN); Universidad de La Frontera; Temuco Chile
| | - R Felmer
- Laboratory of Reproduction; Centre of Reproductive Biotechnology (CEBIOR-BIOREN); Universidad de La Frontera; Temuco Chile
- Department of Agricultural Sciences and Natural Resources; Faculty of Agriculture and Forestry; Universidad de La Frontera; Temuco Chile
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34
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van Gestel RA, Brouwers JF, Ultee A, Helms JB, Gadella BM. Ultrastructure and lipid composition of detergent-resistant membranes derived from mammalian sperm and two types of epithelial cells. Cell Tissue Res 2015; 363:129-145. [PMID: 26378009 PMCID: PMC4700079 DOI: 10.1007/s00441-015-2272-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 08/06/2015] [Indexed: 01/13/2023]
Abstract
Lipid rafts are micro-domains of ordered lipids (Lo phase) in biological membranes. The Lo phase of cellular membranes can be isolated from disordered lipids (Ld phase) after treatment with 1 % Triton X-100 at 4 °C in which the Lo phase forms the detergent-resistant membrane (DRM) fraction. The lipid composition of DRM derived from Madin-Darby canine kidney (MDCK) cells, McArdle cells and porcine sperm is compared with that of the whole cell. Remarkably, the unsaturation and chain length degree of aliphatic chains attached to phospholipids is virtually the same between DRM and whole cells. Cholesterol and sphingomyelin were enriched in DRMs but to a cell-specific molar ratio. Sulfatides (sphingolipids from MDCK cells) were enriched in the DRM while a seminolipid (an alkylacylglycerolipid from sperm) was depleted from the DRM. Treatment with <5 mM methyl-ß-cyclodextrin (MBCD) caused cholesterol removal from the DRM without affecting the composition and amount of the phospholipid while higher levels disrupted the DRM. The substantial amount of (poly)unsaturated phospholipids in DRMs as well as a low stoichiometric amount of cholesterol suggest that lipid rafts in biological membranes are more fluid and dynamic than previously anticipated. Using negative staining, ultrastructural features of DRM were monitored and in all three cell types the DRMs appeared as multi-lamellar vesicular structures with a similar morphology. The detergent resistance is a result of protein–cholesterol and sphingolipid interactions allowing a relatively passive attraction of phospholipids to maintain the Lo phase. For this special issue, the relevance of our findings is discussed in a sperm physiological context.
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Affiliation(s)
- Renske A van Gestel
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine Utrecht University, Yalelaan 2, 3584 CM, Utrecht, The Netherlands
| | - Jos F Brouwers
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine Utrecht University, Yalelaan 2, 3584 CM, Utrecht, The Netherlands
| | - Anton Ultee
- Department of Pathology, Faculty of Veterinary Medicine Utrecht University, Utrecht, The Netherlands
| | - J Bernd Helms
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine Utrecht University, Yalelaan 2, 3584 CM, Utrecht, The Netherlands
| | - Bart M Gadella
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine Utrecht University, Yalelaan 2, 3584 CM, Utrecht, The Netherlands.
- Department of Farm Animal Health, Faculty of Veterinary Medicine Utrecht University, Utrecht, The Netherlands.
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35
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Gangwar DK, Atreja SK. Signalling Events and Associated Pathways Related to the Mammalian Sperm Capacitation. Reprod Domest Anim 2015; 50:705-11. [PMID: 26294224 DOI: 10.1111/rda.12541] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 04/21/2015] [Indexed: 12/22/2022]
Abstract
Capacitation is a biological phenomenon occurring prior to fertilization and is a multiple event process. Many physiological and biochemical changes takes place during the process; these changes are related to lipid composition of membrane, intracellular modulation of ion concentration, protein phosphorylation, sperm movement and membrane permeability. These events occur when the sperm is exposed to the new environment of ion concentration in the female reproductive tract. Ions such as bicarbonate and calcium facilitate capacitation by activating adenylyl cyclase, thus initiating protein kinase A (PKA) signalling cascade. Extracellular-regulated kinase pathway is activated by ligand binding to the membrane receptors and intracellular activation by reactive oxygen species (ROS). Activation of these pathways leads to the phosphorylation of different proteins, which is associated with events such as capacitation, hyperactivation and acrosome reaction that are essential for successful fertilization. Extensive studies were carried out on protein phosphorylation in relation to capacitation, but its role still remains ambiguous.
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Affiliation(s)
- D K Gangwar
- Reproductive Biochemistry Laboratory, Animal Biochemistry Division, National Dairy Research Institute, Karnal, Haryana, India
| | - S K Atreja
- Reproductive Biochemistry Laboratory, Animal Biochemistry Division, National Dairy Research Institute, Karnal, Haryana, India
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36
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Bromfield E, Aitken RJ, Nixon B. Novel characterization of the HSPA2-stabilizing protein BAG6 in human spermatozoa. Mol Hum Reprod 2015; 21:755-69. [DOI: 10.1093/molehr/gav041] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 07/02/2015] [Indexed: 11/13/2022] Open
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37
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Macías-García B, González-Fernández L, Loux SC, Rocha AM, Guimarães T, Peña FJ, Varner DD, Hinrichs K. Effect of calcium, bicarbonate, and albumin on capacitation-related events in equine sperm. Reproduction 2014; 149:87-99. [PMID: 25349439 DOI: 10.1530/rep-14-0457] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Repeatable methods for IVF have not been established in the horse, reflecting the failure of standard capacitating media to induce changes required for fertilization capacity in equine sperm. One important step in capacitation is membrane cholesterol efflux, which in other species is triggered by cholesterol oxidation and is typically enhanced using albumin as a sterol acceptor. We incubated equine sperm in the presence of calcium, BSA, and bicarbonate, alone or in combination. Bicarbonate induced an increase in reactive oxygen species (ROS) that was abolished by the addition of calcium or BSA. Bicarbonate induced protein tyrosine phosphorylation (PY), even in the presence of calcium or BSA. Incubation at high pH enhanced PY but did not increase ROS production. Notably, no combination of these factors was associated with significant cholesterol efflux, as assessed by fluorescent quantitative cholesterol assay and confirmed by filipin staining. By contrast, sperm treated with methyl-β-cyclodextrin showed a significant reduction in cholesterol levels, but no significant increase in PY or ROS. Presence of BSA increased sperm binding to bovine zonae pellucidae in all three stallions. These results show that presence of serum albumin is not associated with a reduction in membrane cholesterol levels in equine sperm, highlighting the failure of equine sperm to exhibit core capacitation-related changes in a standard capacitating medium. These data indicate an atypical relationship among cholesterol efflux, ROS production, and PY in equine sperm. Our findings may help to elucidate factors affecting failure of equine IVF under standard conditions.
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Affiliation(s)
- B Macías-García
- CECA/ICETA - Animal Sciences CentreICBAS-University of Porto, Campus Agrario de Vairão, Rua Padre Armando Quintas, 4485-661 Vairão, PortugalDepartments of Veterinary Physiology and PharmacologyLarge Animal Clinical SciencesCollege of Veterinary Medicine and Biomedical Science, Texas A&M University, College Station, Texas, USALaboratory of Equine ReproductionFaculty of Veterinary Medicine, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain CECA/ICETA - Animal Sciences CentreICBAS-University of Porto, Campus Agrario de Vairão, Rua Padre Armando Quintas, 4485-661 Vairão, PortugalDepartments of Veterinary Physiology and PharmacologyLarge Animal Clinical SciencesCollege of Veterinary Medicine and Biomedical Science, Texas A&M University, College Station, Texas, USALaboratory of Equine ReproductionFaculty of Veterinary Medicine, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - L González-Fernández
- CECA/ICETA - Animal Sciences CentreICBAS-University of Porto, Campus Agrario de Vairão, Rua Padre Armando Quintas, 4485-661 Vairão, PortugalDepartments of Veterinary Physiology and PharmacologyLarge Animal Clinical SciencesCollege of Veterinary Medicine and Biomedical Science, Texas A&M University, College Station, Texas, USALaboratory of Equine ReproductionFaculty of Veterinary Medicine, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain CECA/ICETA - Animal Sciences CentreICBAS-University of Porto, Campus Agrario de Vairão, Rua Padre Armando Quintas, 4485-661 Vairão, PortugalDepartments of Veterinary Physiology and PharmacologyLarge Animal Clinical SciencesCollege of Veterinary Medicine and Biomedical Science, Texas A&M University, College Station, Texas, USALaboratory of Equine ReproductionFaculty of Veterinary Medicine, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - S C Loux
- CECA/ICETA - Animal Sciences CentreICBAS-University of Porto, Campus Agrario de Vairão, Rua Padre Armando Quintas, 4485-661 Vairão, PortugalDepartments of Veterinary Physiology and PharmacologyLarge Animal Clinical SciencesCollege of Veterinary Medicine and Biomedical Science, Texas A&M University, College Station, Texas, USALaboratory of Equine ReproductionFaculty of Veterinary Medicine, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - A M Rocha
- CECA/ICETA - Animal Sciences CentreICBAS-University of Porto, Campus Agrario de Vairão, Rua Padre Armando Quintas, 4485-661 Vairão, PortugalDepartments of Veterinary Physiology and PharmacologyLarge Animal Clinical SciencesCollege of Veterinary Medicine and Biomedical Science, Texas A&M University, College Station, Texas, USALaboratory of Equine ReproductionFaculty of Veterinary Medicine, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - T Guimarães
- CECA/ICETA - Animal Sciences CentreICBAS-University of Porto, Campus Agrario de Vairão, Rua Padre Armando Quintas, 4485-661 Vairão, PortugalDepartments of Veterinary Physiology and PharmacologyLarge Animal Clinical SciencesCollege of Veterinary Medicine and Biomedical Science, Texas A&M University, College Station, Texas, USALaboratory of Equine ReproductionFaculty of Veterinary Medicine, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - F J Peña
- CECA/ICETA - Animal Sciences CentreICBAS-University of Porto, Campus Agrario de Vairão, Rua Padre Armando Quintas, 4485-661 Vairão, PortugalDepartments of Veterinary Physiology and PharmacologyLarge Animal Clinical SciencesCollege of Veterinary Medicine and Biomedical Science, Texas A&M University, College Station, Texas, USALaboratory of Equine ReproductionFaculty of Veterinary Medicine, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - D D Varner
- CECA/ICETA - Animal Sciences CentreICBAS-University of Porto, Campus Agrario de Vairão, Rua Padre Armando Quintas, 4485-661 Vairão, PortugalDepartments of Veterinary Physiology and PharmacologyLarge Animal Clinical SciencesCollege of Veterinary Medicine and Biomedical Science, Texas A&M University, College Station, Texas, USALaboratory of Equine ReproductionFaculty of Veterinary Medicine, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - K Hinrichs
- CECA/ICETA - Animal Sciences CentreICBAS-University of Porto, Campus Agrario de Vairão, Rua Padre Armando Quintas, 4485-661 Vairão, PortugalDepartments of Veterinary Physiology and PharmacologyLarge Animal Clinical SciencesCollege of Veterinary Medicine and Biomedical Science, Texas A&M University, College Station, Texas, USALaboratory of Equine ReproductionFaculty of Veterinary Medicine, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain CECA/ICETA - Animal Sciences CentreICBAS-University of Porto, Campus Agrario de Vairão, Rua Padre Armando Quintas, 4485-661 Vairão, PortugalDepartments of Veterinary Physiology and PharmacologyLarge Animal Clinical SciencesCollege of Veterinary Medicine and Biomedical Science, Texas A&M University, College Station, Texas, USALaboratory of Equine ReproductionFaculty of Veterinary Medicine, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
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Varner DD, Gibb Z, Aitken RJ. Stallion fertility: a focus on the spermatozoon. Equine Vet J 2014; 47:16-24. [PMID: 24943233 DOI: 10.1111/evj.12308] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 06/03/2014] [Indexed: 11/30/2022]
Abstract
Stallion fertility is a vast subject, with a wide array of permutations that can impact reproductive performance in either positive or negative ways. This review is intended to address a mere segment of the male fertility issue, but the very essence of the male contribution to fertilisation, that of the spermatozoon. Spermatozoal ultrastructure and form-to-function are detailed and spermatozoal metabolism is discussed, with specific reference to distinctive characteristics of stallion spermatozoa. Lastly, methods for assessment of spermatozoal function are considered, with emphasis on spermatozoal motility, the acrosome reaction and spermatozoon-oocyte interactions. Closing comments address the need for development and standardisation of molecular-based assays for use with spermatozoa of stallions whose subfertility cannot be explained with conventional tests.
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Affiliation(s)
- D D Varner
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, USA
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