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Chávez JC, Carrasquel-Martínez G, Hernández-Garduño S, Matamoros Volante A, Treviño CL, Nishigaki T, Darszon A. Cytosolic and Acrosomal pH Regulation in Mammalian Sperm. Cells 2024; 13:865. [PMID: 38786087 PMCID: PMC11120249 DOI: 10.3390/cells13100865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 05/07/2024] [Accepted: 05/09/2024] [Indexed: 05/25/2024] Open
Abstract
As in most cells, intracellular pH regulation is fundamental for sperm physiology. Key sperm functions like swimming, maturation, and a unique exocytotic process, the acrosome reaction, necessary for gamete fusion, are deeply influenced by pH. Sperm pH regulation, both intracellularly and within organelles such as the acrosome, requires a coordinated interplay of various transporters and channels, ensuring that this cell is primed for fertilization. Consistent with the pivotal importance of pH regulation in mammalian sperm physiology, several of its unique transporters are dependent on cytosolic pH. Examples include the Ca2+ channel CatSper and the K+ channel Slo3. The absence of these channels leads to male infertility. This review outlines the main transport elements involved in pH regulation, including cytosolic and acrosomal pH, that participate in these complex functions. We present a glimpse of how these transporters are regulated and how distinct sets of them are orchestrated to allow sperm to fertilize the egg. Much research is needed to begin to envision the complete set of players and the choreography of how cytosolic and organellar pH are regulated in each sperm function.
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Affiliation(s)
- Julio C. Chávez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología (IBT), Universidad Nacional Autónoma de México (UNAM), Cuernavaca 62210, Morelos, Mexico; (J.C.C.); (G.C.-M.)
| | - Gabriela Carrasquel-Martínez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología (IBT), Universidad Nacional Autónoma de México (UNAM), Cuernavaca 62210, Morelos, Mexico; (J.C.C.); (G.C.-M.)
- CITMER, Medicina Reproductiva, México City 11520, Mexico
| | - Sandra Hernández-Garduño
- Departamento de Morfología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México (UNAM), México City 04510, Mexico;
| | - Arturo Matamoros Volante
- Department of Electrical and Computer Engineering and School of Biomedical Engineering, Colorado State University, Fort Collins, CO 80523, USA;
| | - Claudia L. Treviño
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología (IBT), Universidad Nacional Autónoma de México (UNAM), Cuernavaca 62210, Morelos, Mexico; (J.C.C.); (G.C.-M.)
| | - Takuya Nishigaki
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología (IBT), Universidad Nacional Autónoma de México (UNAM), Cuernavaca 62210, Morelos, Mexico; (J.C.C.); (G.C.-M.)
| | - Alberto Darszon
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología (IBT), Universidad Nacional Autónoma de México (UNAM), Cuernavaca 62210, Morelos, Mexico; (J.C.C.); (G.C.-M.)
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Gruber FS, Richardson A, Johnston ZC, Myles R, Norcross NR, Day DP, Georgiou I, Sesma-Sanz L, Wilson C, Read KD, Martins da Silva S, Barratt CLR, Gilbert IH, Swedlow JR. Sperm Toolbox-A selection of small molecules to study human spermatozoa. PLoS One 2024; 19:e0297666. [PMID: 38377053 PMCID: PMC10878532 DOI: 10.1371/journal.pone.0297666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 01/11/2024] [Indexed: 02/22/2024] Open
Abstract
Male contraceptive options and infertility treatments are limited, and almost all innovation has been limited to updates to medically assisted reproduction protocols and methods. To accelerate the development of drugs that can either improve or inhibit fertility, we established a small molecule library as a toolbox for assay development and screening campaigns using human spermatozoa. We have profiled all compounds in the Sperm Toolbox in several automated high-throughput assays that measure stimulation or inhibition of sperm motility or the acrosome reaction. We have assayed motility under non-capacitating and capacitating conditions to distinguish between pathways operating under these different physiological states. We also assayed cell viability to ensure any effects on sperm function are specific. A key advantage of our studies is that all compounds are assayed together in the same experimental conditions, which allows quantitative comparisons of their effects in complementary functional assays. We have combined the resulting datasets to generate fingerprints of the Sperm Toolbox compounds on sperm function. The data are included in an on-line R-based app for convenient querying.
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Affiliation(s)
- Franz S. Gruber
- Divisions of Computational Biology and Molecular, Cell and Developmental Biology, and National Phenotypic Screening Centre, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Anthony Richardson
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Zoe C. Johnston
- Division of Systems Medicine, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, United Kingdom
| | - Rachel Myles
- Division of Systems Medicine, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, United Kingdom
| | - Neil R. Norcross
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - David P. Day
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Irene Georgiou
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Laura Sesma-Sanz
- Divisions of Computational Biology and Molecular, Cell and Developmental Biology, and National Phenotypic Screening Centre, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Caroline Wilson
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Kevin D. Read
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Sarah Martins da Silva
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Christopher L. R. Barratt
- Division of Systems Medicine, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, United Kingdom
| | - Ian H. Gilbert
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Jason R. Swedlow
- Divisions of Computational Biology and Molecular, Cell and Developmental Biology, and National Phenotypic Screening Centre, School of Life Sciences, University of Dundee, Dundee, United Kingdom
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Arreola J, Pérez-Cornejo P, Segura-Covarrubias G, Corral-Fernández N, León-Aparicio D, Guzmán-Hernández ML. Function and Regulation of the Calcium-Activated Chloride Channel Anoctamin 1 (TMEM16A). Handb Exp Pharmacol 2024; 283:101-151. [PMID: 35768554 DOI: 10.1007/164_2022_592] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Various human tissues express the calcium-activated chloride channel Anoctamin 1 (ANO1), also known as TMEM16A. ANO1 allows the passive chloride flux that controls different physiological functions ranging from muscle contraction, fluid and hormone secretion, gastrointestinal motility, and electrical excitability. Overexpression of ANO1 is associated with pathological conditions such as hypertension and cancer. The molecular cloning of ANO1 has led to a surge in structural, functional, and physiological studies of the channel in several tissues. ANO1 is a homodimer channel harboring two pores - one in each monomer - that work independently. Each pore is activated by voltage-dependent binding of two intracellular calcium ions to a high-affinity-binding site. In addition, the binding of phosphatidylinositol 4,5-bisphosphate to sites scattered throughout the cytosolic side of the protein aids the calcium activation process. Furthermore, many pharmacological studies have established ANO1 as a target of promising compounds that could treat several illnesses. This chapter describes our current understanding of the physiological roles of ANO1 and its regulation under physiological conditions as well as new pharmacological compounds with potential therapeutic applications.
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Affiliation(s)
- Jorge Arreola
- Physics Institute, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico.
| | - Patricia Pérez-Cornejo
- Department of Physiology and Biophysics, School of Medicine of Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - Guadalupe Segura-Covarrubias
- Physics Institute, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH, USA
| | - Nancy Corral-Fernández
- Department of Physiology and Biophysics, School of Medicine of Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - Daniel León-Aparicio
- Physics Institute, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
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Benko F, Urminská D, Ďuračka M, Tvrdá E. Signaling Roleplay between Ion Channels during Mammalian Sperm Capacitation. Biomedicines 2023; 11:2519. [PMID: 37760960 PMCID: PMC10525812 DOI: 10.3390/biomedicines11092519] [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: 07/30/2023] [Revised: 08/31/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023] Open
Abstract
In order to accomplish their primary goal, mammalian spermatozoa must undergo a series of physiological, biochemical, and functional changes crucial for the acquisition of fertilization ability. Spermatozoa are highly polarized cells, which must swiftly respond to ionic changes on their passage through the female reproductive tract, and which are necessary for male gametes to acquire their functional competence. This review summarizes the current knowledge about specific ion channels and transporters located in the mammalian sperm plasma membrane, which are intricately involved in the initiation of changes within the ionic milieu of the sperm cell, leading to variations in the sperm membrane potential, membrane depolarization and hyperpolarization, changes in sperm motility and capacitation to further lead to the acrosome reaction and sperm-egg fusion. We also discuss the functionality of selected ion channels in male reproductive health and/or disease since these may become promising targets for clinical management of infertility in the future.
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Affiliation(s)
- Filip Benko
- Institute of Biotechnology, Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia; (D.U.); (E.T.)
| | - Dana Urminská
- Institute of Biotechnology, Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia; (D.U.); (E.T.)
| | - Michal Ďuračka
- AgroBioTech Research Centre, Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia;
| | - Eva Tvrdá
- Institute of Biotechnology, Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia; (D.U.); (E.T.)
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Akhondzadeh S, Farshad A, Rostamzadeh J, Sharafi M. Effects of Antifreeze Protein Type I and Glycerol in Diluents on Cryopreserved Goat Epididymal Sperm. Biopreserv Biobank 2023; 21:65-73. [PMID: 35426727 DOI: 10.1089/bio.2021.0150] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The effect of antifreeze protein (AFP) as a cryoprotectant used in different concentrations of glycerol on post-thaw quality of epididymal sperm was investigated. Sperm were isolated from 50 testicles, obtained from 25 healthy mature goat bucks, with progressive motility >80%, and total morphological abnormalities <10% were pooled in each replication. The semen samples were diluted with Tris-citrate-fructose-soybean lecithin extender containing different concentration of AFP [0 μg/mL (A0), 5 μg/mL (A5), 10 μg/mL (A10)]. Each concentration of AFP was added in an extender containing either 7% (G7) or 5% (G5) glycerol. Post-thaw total and progressive motility were found to be higher (p < 0.05) in groups A5G5 and A5G7. Plasma membrane integrity, sperm acrosome integrity, DNA integrity, acrosome intact sperm, and mitochondrial membrane potential were found to be higher (p < 0.05) in groups A5G5 and A10G5. Sperm viability was found to be higher (p < 0.05) in group A5G5, while lipid peroxidation was recorded lower (p < 0.05) in groups A5G5 and A5G7. Regarding the apoptosis occurrence, the results demonstrate higher (p < 0.05) live post-thawed spermatozoa for groups containing 5 μg/mL AFP with 5% and 7% glycerol in addition to the lowest (p < 0.05) value for groups containing 0 μg/mL AFP with 5% and 7% glycerol. Based on these results, the present study concludes that the addition of 5 μg/mL AFP in combination with 5% glycerol in freezing extender improves the post-thaw quality, structure, and function parameters for buck spermatozoa.
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Affiliation(s)
- Saeed Akhondzadeh
- Laboratory of Reproduction Biology, Department of Animal Science, Faculty of Agriculture, University of Kurdistan, Sanandaj, Kurdistan, Iran
| | - Abbas Farshad
- Laboratory of Reproduction Biology, Department of Animal Science, Faculty of Agriculture, University of Kurdistan, Sanandaj, Kurdistan, Iran
| | - Jalal Rostamzadeh
- Laboratory of Reproduction Biology, Department of Animal Science, Faculty of Agriculture, University of Kurdistan, Sanandaj, Kurdistan, Iran
| | - Mohsen Sharafi
- Department of Embryology at Reproductive Biomedicine Research Center, Royan Institute for Reproductive, ACECR, Tehran, Iran
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Darbandi S, Darbandi M, Khorram Khorshid HR, Sengupta P. Electrophysiology of Human Gametes: A Systematic Review. World J Mens Health 2022; 40:442-455. [PMID: 35021309 PMCID: PMC9253800 DOI: 10.5534/wjmh.210107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 09/05/2021] [Accepted: 09/14/2021] [Indexed: 11/15/2022] Open
Abstract
PURPOSE Oocytes and spermatozoa are electrogenic cells with the ability to respond to electrical stimuli and modulate their electrical properties accordingly. Determination of the ionic events during the gamete maturation helps to design suitable culture media for gametes in assisted reproductive technology (ART). The present systematic review focuses on the electrophysiology of human gametes during different stages of maturation and also during fertilization. MATERIALS AND METHODS The reports published in the English language between January 2000 and July 2021 were extracted from various electronic scientific databases following the PRISMA checklist using specific MeSH keywords. RESULTS Subsequent to the screening process with defined inclusion and exclusion criteria, 60 articles have been included in this review. Among them, 11 articles were directly related to the electrophysiology of human oocytes and 49 physiology department to the electrophysiology of human spermatozoa. CONCLUSIONS Gametes generate electrical currents by ionic exchange, particularly Na+, K+, Cl-, H+, Zn2+, Cu2+, Se2+, Mg2+, HCO3-, and Ca2+ through specific ion channels in different stages of gamete maturation. The ionic concentrations, pH, and other physicochemical variables are modulated during the gametogenesis, maturation, activation, and the fertilization process following gamete function and metabolism. The electrical properties of human gametes change during different stages of maturation. Although it is demonstrated that the electrical properties are significant regulators of cell signaling and are fundamental to gamete maturation and fertilization, their exact roles in these processes are still poorly understood. Further research is required to unveil the intricate electrophysiological processes of human gamete maturation.
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Affiliation(s)
- Sara Darbandi
- Fetal Health Research Center, Hope Generation Foundation, Tehran, Iran
| | - Mahsa Darbandi
- Fetal Health Research Center, Hope Generation Foundation, Tehran, Iran
| | - Hamid Reza Khorram Khorshid
- Gene Therapy and Regenerative Medicine Research Center, Hope Generation Foundation, Tehran, Iran
- Personalized Medicine and Genometabolomics Research Center, Hope Generation Foundation, Tehran, Iran
| | - Pallav Sengupta
- Department of Physiology, Faculty of Medicine, Biosciences and Nursing, MAHSA University, Jenjarom, Selangor, Malaysia
- School of Medical Sciences, Bharath Institute of Higher Education and Research (BIHER), Chennai, India.
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Cavarocchi E, Whitfield M, Saez F, Touré A. Sperm Ion Transporters and Channels in Human Asthenozoospermia: Genetic Etiology, Lessons from Animal Models, and Clinical Perspectives. Int J Mol Sci 2022; 23:ijms23073926. [PMID: 35409285 PMCID: PMC8999829 DOI: 10.3390/ijms23073926] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/29/2022] [Accepted: 03/30/2022] [Indexed: 12/18/2022] Open
Abstract
In mammals, sperm fertilization potential relies on efficient progression within the female genital tract to reach and fertilize the oocyte. This fundamental property is supported by the flagellum, an evolutionarily conserved organelle that provides the mechanical force for sperm propulsion and motility. Importantly several functional maturation events that occur during the journey of the sperm cells through the genital tracts are necessary for the activation of flagellar beating and the acquisition of fertilization potential. Ion transporters and channels located at the surface of the sperm cells have been demonstrated to be involved in these processes, in particular, through the activation of downstream signaling pathways and the promotion of novel biochemical and electrophysiological properties in the sperm cells. We performed a systematic literature review to describe the currently known genetic alterations in humans that affect sperm ion transporters and channels and result in asthenozoospermia, a pathophysiological condition defined by reduced or absent sperm motility and observed in nearly 80% of infertile men. We also present the physiological relevance and functional mechanisms of additional ion channels identified in the mouse. Finally, considering the state-of-the art, we discuss future perspectives in terms of therapeutics of asthenozoospermia and male contraception.
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Affiliation(s)
- Emma Cavarocchi
- Institute for Advanced Biosciences, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, 38000 Grenoble, France; (E.C.); (M.W.)
| | - Marjorie Whitfield
- Institute for Advanced Biosciences, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, 38000 Grenoble, France; (E.C.); (M.W.)
| | - Fabrice Saez
- UMR GReD Institute (Génétique Reproduction & Développement) CNRS 6293, INSERM U1103, Team «Mécanismes de L’Infertilité Mâle Post-Testiculaire», Université Clermont Auvergne, 63000 Clermont-Ferrand, France
- Correspondence: (F.S.); (A.T.)
| | - Aminata Touré
- Institute for Advanced Biosciences, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, 38000 Grenoble, France; (E.C.); (M.W.)
- Correspondence: (F.S.); (A.T.)
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8
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Perspectives on Potential Fatty Acid Modulations of Motility Associated Human Sperm Ion Channels. Int J Mol Sci 2022; 23:ijms23073718. [PMID: 35409078 PMCID: PMC8998313 DOI: 10.3390/ijms23073718] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 03/25/2022] [Accepted: 03/25/2022] [Indexed: 02/06/2023] Open
Abstract
Human spermatozoan ion channels are specifically distributed in the spermatozoan membrane, contribute to sperm motility, and are associated with male reproductive abnormalities. Calcium, potassium, protons, sodium, and chloride are the main ions that are regulated across this membrane, and their intracellular concentrations are crucial for sperm motility. Fatty acids (FAs) affect sperm quality parameters, reproductive pathologies, male fertility, and regulate ion channel functions in other cells. However, to date the literature is insufficient to draw any conclusions regarding the effects of FAs on human spermatozoan ion channels. Here, we aimed to discern the possible effects of FAs on spermatozoan ion channels and direct guidance for future research. After investigating the effects of FAs on characteristics related to human spermatozoan motility, reproductive pathologies, and the modulation of similar ion channels in other cells by FAs, we extrapolated polyunsaturated FAs (PUFAs) to have the highest potency in modulating sperm ion channels to increase sperm motility. Of the PUFAs, the ω-3 unsaturated fatty acids have the greatest effect. We speculate that saturated and monounsaturated FAs will have little to no effect on sperm ion channel activity, though the possible effects could be opposite to those of the PUFAs, considering the differences between FA structure and behavior.
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Arunkumar R, Kumaresan A, Sinha MK, Elango K, Ebenezer Samuel King JP, Nag P, Karuthadurai T, Baithalu RK, Mohanty TK, Kumar R, Datta TK. The cryopreservation process induces alterations in proteins associated with bull sperm quality: The equilibration process could be a probable critical control point. Front Endocrinol (Lausanne) 2022; 13:1064956. [PMID: 36568066 PMCID: PMC9787546 DOI: 10.3389/fendo.2022.1064956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Accepted: 11/21/2022] [Indexed: 12/13/2022] Open
Abstract
The present study quantitatively characterized the proteomic changes in bull spermatozoa induced by the cryopreservation process. We performed high-throughput comparative global proteomic profiling of freshly ejaculated (before cryopreservation), equilibrated (refrigerated storage; during cryopreservation), and frozen (ultralow temperature; after cryopreservation) bull spermatozoa. Using the liquid chromatography-mass spectrometry (LC-MS/MS) technique, a total of 1,692, 1,415, and 1,286 proteins were identified in fresh, equilibrated, and cryopreserved spermatozoa, respectively. When the proteome of fresh spermatozoa was compared with equilibrated spermatozoa, we found that 166 proteins were differentially expressed. When equilibrated spermatozoa were compared with cryopreserved spermatozoa, we found that 147 proteins were differentially expressed between them. Similarly, we found that 156 proteins were differentially expressed between fresh and cryopreserved spermatozoa. Among these proteins, the abundance of 105 proteins was lowered during the equilibration process itself, while the abundance of 43 proteins was lowered during ultralow temperature preservation. Remarkably, the equilibration process lowered the abundance of sperm proteins involved in energy metabolism, structural integrity, and DNA repair and increased the abundance of proteins associated with proteolysis and protein degradation. The abundance of sperm proteins associated with metabolism, cGMP-PKG (cyclic guanosine 3',5'-monophosphate-dependent protein kinase G) signaling, and regulation of the actin cytoskeleton was also altered during the equilibration process. Collectively, the present study showed that the equilibration step in the bull sperm cryopreservation process was the critical point for sperm proteome, during which a majority of proteomic alterations in sperm occurred. These findings are valuable for developing efficient protocols to minimize protein damage and to improve the quality and fertility of cryopreserved bull spermatozoa.
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Affiliation(s)
- Ramasamy Arunkumar
- Theriogenology Laboratory, Southern Regional Station of ICAR-National Dairy Research Institute, Bengaluru, India
| | - Arumugam Kumaresan
- Theriogenology Laboratory, Southern Regional Station of ICAR-National Dairy Research Institute, Bengaluru, India
- *Correspondence: Arumugam Kumaresan, ;
| | - Manish Kumar Sinha
- Theriogenology Laboratory, Southern Regional Station of ICAR-National Dairy Research Institute, Bengaluru, India
| | - Kamaraj Elango
- Theriogenology Laboratory, Southern Regional Station of ICAR-National Dairy Research Institute, Bengaluru, India
| | | | - Pradeep Nag
- Theriogenology Laboratory, Southern Regional Station of ICAR-National Dairy Research Institute, Bengaluru, India
| | - Thirumalaisamy Karuthadurai
- Theriogenology Laboratory, Southern Regional Station of ICAR-National Dairy Research Institute, Bengaluru, India
| | - Rubina Kumari Baithalu
- Animal Reproduction, Gynaecology and Obstetrics, ICAR-National Dairy Research Institute, Karnal, India
| | - Tushar Kumar Mohanty
- Animal Reproduction, Gynaecology and Obstetrics, ICAR-National Dairy Research Institute, Karnal, India
| | - Rakesh Kumar
- Animal Genomics Laboratory, Indian Council for Agricultural Research (ICAR)-National Dairy Research Institute, Karnal, India
| | - Tirtha Kumar Datta
- Animal Genomics Laboratory, Indian Council for Agricultural Research (ICAR)-National Dairy Research Institute, Karnal, India
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Aguado-García A, Priego-Espinosa DA, Aldana A, Darszon A, Martínez-Mekler G. Mathematical model reveals that heterogeneity in the number of ion transporters regulates the fraction of mouse sperm capacitation. PLoS One 2021; 16:e0245816. [PMID: 34793454 PMCID: PMC8601445 DOI: 10.1371/journal.pone.0245816] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2020] [Accepted: 10/20/2021] [Indexed: 12/03/2022] Open
Abstract
Capacitation is a complex maturation process mammalian sperm must undergo in the female genital tract to be able to fertilize an egg. This process involves, amongst others, physiological changes in flagellar beating pattern, membrane potential, intracellular ion concentrations and protein phosphorylation. Typically, in a capacitation medium, only a fraction of sperm achieve this state. The cause for this heterogeneous response is still not well understood and remains an open question. Here, one of our principal results is to develop a discrete regulatory network, with mostly deterministic dynamics in conjunction with some stochastic elements, for the main biochemical and biophysical processes involved in the early events of capacitation. The model criterion for capacitation requires the convergence of specific levels of a select set of nodes. Besides reproducing several experimental results and providing some insight on the network interrelations, the main contribution of the model is the suggestion that the degree of variability in the total amount and individual number of ion transporters among spermatozoa regulates the fraction of capacitated spermatozoa. This conclusion is consistent with recently reported experimental results. Based on this mathematical analysis, experimental clues are proposed for the control of capacitation levels. Furthermore, cooperative and interference traits that become apparent in the modelling among some components also call for future theoretical and experimental studies.
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Affiliation(s)
- Alejandro Aguado-García
- Instituto de Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, México
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | | | - Andrés Aldana
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
- Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, CDMX, México
| | - Alberto Darszon
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Gustavo Martínez-Mekler
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
- Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, CDMX, México
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Hess S, Pouzat C, Paeger L, Pippow A, Kloppenburg P. Analysis of neuronal Ca 2+ handling properties by combining perforated patch clamp recordings and the added buffer approach. Cell Calcium 2021; 97:102411. [PMID: 34082340 DOI: 10.1016/j.ceca.2021.102411] [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: 08/04/2020] [Revised: 03/25/2021] [Accepted: 04/15/2021] [Indexed: 12/11/2022]
Abstract
Ca2+ functions as an important intracellular signal for a wide range of cellular processes. These processes are selectively activated by controlled spatiotemporal dynamics of the free cytosolic Ca2+. Intracellular Ca2+ dynamics are regulated by numerous cellular parameters. Here, we established a new way to determine neuronal Ca2+ handling properties by combining the 'added buffer' approach [1] with perforated patch-clamp recordings [2]. Since the added buffer approach typically employs the standard whole-cell configuration for concentration-controlled Ca2+ indicator loading, it only allows for the reliable estimation of the immobile fraction of intracellular Ca2+ buffers. Furthermore, crucial components of intracellular signaling pathways are being washed out during prolonged whole-cell recordings, leading to cellular deterioration. By combining the added buffer approach with perforated patch-clamp recordings, these issues are circumvented, allowing the precise quantification of the cellular Ca2+ handling properties, including immobile as well as mobile Ca2+ buffers.
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Affiliation(s)
- Simon Hess
- Institute for Zoology, Biocenter, Cologne Excellence Cluster in Aging Associated Diseases (CECAD), and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Christophe Pouzat
- Université de Paris, CNRS, MAP5 UMR 8145, 45, rue des Saints-Pères, 75006 Paris, France
| | - Lars Paeger
- Institute for Zoology, Biocenter, Cologne Excellence Cluster in Aging Associated Diseases (CECAD), and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Andreas Pippow
- Institute for Zoology, Biocenter, Cologne Excellence Cluster in Aging Associated Diseases (CECAD), and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Peter Kloppenburg
- Institute for Zoology, Biocenter, Cologne Excellence Cluster in Aging Associated Diseases (CECAD), and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.
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12
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Nowicka-Bauer K, Szymczak-Cendlak M. Structure and Function of Ion Channels Regulating Sperm Motility-An Overview. Int J Mol Sci 2021; 22:ijms22063259. [PMID: 33806823 PMCID: PMC8004680 DOI: 10.3390/ijms22063259] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 03/18/2021] [Accepted: 03/19/2021] [Indexed: 12/18/2022] Open
Abstract
Sperm motility is linked to the activation of signaling pathways that trigger movement. These pathways are mainly dependent on Ca2+, which acts as a secondary messenger. The maintenance of adequate Ca2+ concentrations is possible thanks to proper concentrations of other ions, such as K+ and Na+, among others, that modulate plasma membrane potential and the intracellular pH. Like in every cell, ion homeostasis in spermatozoa is ensured by a vast spectrum of ion channels supported by the work of ion pumps and transporters. To achieve success in fertilization, sperm ion channels have to be sensitive to various external and internal factors. This sensitivity is provided by specific channel structures. In addition, novel sperm-specific channels or isoforms have been found with compositions that increase the chance of fertilization. Notably, the most significant sperm ion channel is the cation channel of sperm (CatSper), which is a sperm-specific Ca2+ channel required for the hyperactivation of sperm motility. The role of other ion channels in the spermatozoa, such as voltage-gated Ca2+ channels (VGCCs), Ca2+-activated Cl-channels (CaCCs), SLO K+ channels or voltage-gated H+ channels (VGHCs), is to ensure the activation and modulation of CatSper. As the activation of sperm motility differs among metazoa, different ion channels may participate; however, knowledge regarding these channels is still scarce. In the present review, the roles and structures of the most important known ion channels are described in regard to regulation of sperm motility in animals.
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Affiliation(s)
- Karolina Nowicka-Bauer
- Department of Chemical Physics, Faculty of Chemistry, Adam Mickiewicz University in Poznań, 61-614 Poznan, Poland
- Correspondence:
| | - Monika Szymczak-Cendlak
- Department of Animal Physiology and Development, Faculty of Biology, Adam Mickiewicz University in Poznań, 61-614 Poznan, Poland;
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Tektemur A, Etem Önalan E, Kaya Tektemur N, Güngör İH, Türk G, Kuloğlu T. Verapamil-induced ion channel and miRNA expression changes in rat testis and/or spermatozoa may be associated with male infertility. Andrologia 2020; 52:e13778. [PMID: 32725937 DOI: 10.1111/and.13778] [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: 04/30/2020] [Revised: 06/25/2020] [Accepted: 07/07/2020] [Indexed: 12/22/2022] Open
Abstract
The effect of verapamil, a calcium channel blocker, on male fertility in terms of ion channel and miRNA gene expressions in testis/spermatozoa was evaluated in this study. Rats were divided into sham and verapamil groups (n = 15). Verapamil was performed orally for 60 days. Sperm parameters and levels of serum follicle-stimulating hormone (FSH), luteinising hormone (LH) and testosterone (T) hormones were analysed. Alterations of microRNA (miRNA) and ion channel gene expressions in spermatozoa/testis were detected by using qPCR. Verapamil treatment reduced sperm concentration. Increased serum FSH, LH and T hormone levels were detected. Upregulated transient receptor potential cation channel subfamily V member 5 (TRPV5) and potassium voltage-gated channel subfamily J member 11 (KCNJ11) gene expressions and downregulated miR-let-7b, miR-10a, miR-320 and miR-760 expressions were found in testis of verapamil group. However, upregulated anoctamin 1 (ANO1), ATP-binding cassette subfamily C member 9 (ABCC9), miR-27a and miR-130a expressions and downregulated miR-20a, miR-92a, miR-132, miR-320 and miR-760 expressions were detected in spermatozoa. In addition, these altered gene expressions were found to be associated with decreased sperm concentration. The results indicate that the changes in testicular and/or spermatozoal ion channels and miRNA expressions due to verapamil treatment may affect male fertility.
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Affiliation(s)
- Ahmet Tektemur
- Department of Medical Biology, Faculty of Medicine, Firat University, Elazig, Turkey
| | - Ebru Etem Önalan
- Department of Medical Biology, Faculty of Medicine, Firat University, Elazig, Turkey
| | - Nalan Kaya Tektemur
- Department of Histology and Embriology, Faculty of Medicine, Firat University, Elazig, Turkey
| | - İbrahim Halil Güngör
- Department of Reproduction and Artificial Insemination, Faculty of Veterinary Medicine, Firat University, Elazig, Turkey
| | - Gaffari Türk
- Department of Reproduction and Artificial Insemination, Faculty of Veterinary Medicine, Firat University, Elazig, Turkey
| | - Tuncay Kuloğlu
- Department of Histology and Embriology, Faculty of Medicine, Firat University, Elazig, Turkey
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14
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Cordero-Martínez J, Flores-Alonso JC, Aguirre-Alvarado C, Oviedo N, Alcántara-Farfán V, García-Pérez CA, Bermúdez-Ruiz KF, Jiménez-Gutiérrez GE, Rodríguez-Páez L. Influence of Echeveria gibbiflora DC aqueous crude extract on mouse sperm energy metabolism and calcium-dependent channels. JOURNAL OF ETHNOPHARMACOLOGY 2020; 248:112321. [PMID: 31655146 DOI: 10.1016/j.jep.2019.112321] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 09/27/2019] [Accepted: 10/16/2019] [Indexed: 06/10/2023]
Abstract
ETHNOPHARMACOLOGY RELEVANCE In traditional Mexican medicine, Echeveria gibbiflora DC has been used as a vaginal post-coital rinse to prevent pregnancy. The aqueous crude extract (OBACE) induces sperm immobilization/agglutination and a hypotonic-like effect, likely attributed to the high concentration of calcium bis-(hydrogen-1-malate) hexahydrate [Ca2+ (C4H5O5)2•6H2O]. Likewise, OBACE impedes the increase of [Ca2+]i during capacitation. AIM OF THE STUDY Evaluate the effect of OBACE on sperm energy metabolism and the underlying mechanism of action on sperm-specific channel. MATERIAL AND METHODS In vitro, we quantified the mouse sperm immobilization effect and the antifertility potential of OBACE. The energetic metabolism status was also evaluated by assessing the ATP levels, general mitochondrial activity, mitochondrial membrane potential, and enzymatic activity of three key enzymes of energy metabolism. Furthermore, the effect of the ion efflux of Cl- and K+, as well as the pHi, were investigated in order to elucidate which channel is suitable to perform an in silico study. RESULTS Total and progressive motility notably decreased, as did fertility rates. ATP levels, mitochondrial activity and membrane potential were reduced. Furthermore, the activities of the three enzymes decreased. Neither Cl- or K+ channels activities were affected at low concentrations of OBACE; nevertheless, pHi did not alkalinize. Finally, an in silico analysis was performed between the Catsper channel and calcium bis-(hydrogen-1-malate) hexahydrate, which showed a possible blockade of this sperm cation channel. CONCLUSION The results were useful to elucidate the effect of OBACE and to propose it as a future male contraceptive.
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Affiliation(s)
- Joaquín Cordero-Martínez
- Laboratorio de Bioquímica Farmacológica, Departamento de Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, 11340, Mexico
| | - Juan Carlos Flores-Alonso
- Laboratorio de Biología de la Reproducción, Centro de Investigación Biomédica de Oriente, Hospital General de Zona #5, Metepec, Instituto Mexicano del Seguro Social, Metepec, Puebla, Mexico
| | - Charmina Aguirre-Alvarado
- Laboratorio de Bioquímica Farmacológica, Departamento de Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, 11340, Mexico; Unidad de Investigación Médica en Inmunología e Infectología, Centro Médico Nacional, La Raza, IMSS, Ciudad de México, Mexico
| | - Norma Oviedo
- Unidad de Investigación Médica en Inmunología e Infectología, Centro Médico Nacional, La Raza, IMSS, Ciudad de México, Mexico
| | - Verónica Alcántara-Farfán
- Laboratorio de Bioquímica Farmacológica, Departamento de Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, 11340, Mexico
| | | | - Karla Fernanda Bermúdez-Ruiz
- Laboratorio de Bioquímica Farmacológica, Departamento de Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, 11340, Mexico
| | - Guadalupe Elizabeth Jiménez-Gutiérrez
- Laboratorio de Bioquímica Farmacológica, Departamento de Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, 11340, Mexico
| | - Lorena Rodríguez-Páez
- Laboratorio de Bioquímica Farmacológica, Departamento de Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, 11340, Mexico.
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15
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Brown SG, Publicover SJ, Barratt CLR, Martins da Silva SJ. Human sperm ion channel (dys)function: implications for fertilization. Hum Reprod Update 2019; 25:758-776. [PMID: 31665287 PMCID: PMC6847974 DOI: 10.1093/humupd/dmz032] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 07/14/2019] [Accepted: 08/13/2019] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Intensive research on sperm ion channels has identified members of several ion channel families in both mouse and human sperm. Gene knock-out studies have unequivocally demonstrated the importance of the calcium and potassium conductances in sperm for fertility. In both species, the calcium current is carried by the highly complex cation channel of sperm (CatSper). In mouse sperm, the potassium current has been conclusively shown to be carried by a channel consisting of the pore forming subunit SLO3 and auxiliary subunit leucine-rich repeat-containing 52 (LRRC52). However, in human sperm it is controversial whether the pore forming subunit of the channel is composed of SLO3 and/or SLO1. Deciphering the role of the proton-specific Hv1 channel is more challenging as it is only expressed in human sperm. However, definitive evidence for a role in, and importance for, human fertility can only be determined through studies using clinical samples. OBJECTIVE AND RATIONALE This review aims to provide insight into the role of sperm ion channels in human fertilization as evidenced from recent studies of sperm from infertile men. We also summarize the key discoveries from mouse ion channel knock-out models and contrast the properties of mouse and human CatSper and potassium currents. We detail the evidence for, and consequences of, defective ion channels in human sperm and discuss hypotheses to explain how defects arise and why affected sperm have impaired fertilization potential. SEARCH METHODS Relevant studies were identified using PubMed and were limited to ion channels that have been characterized in mouse and human sperm. Additional notable examples from other species are included as appropriate. OUTCOMES There are now well-documented fundamental differences between the properties of CatSper and potassium channel currents in mouse and human sperm. However, in both species, sperm lacking either channel cannot fertilize in vivo and CatSper-null sperm also fail to fertilize at IVF. Sperm-lacking potassium currents are capable of fertilizing at IVF, albeit at a much lower rate. However, additional complex and heterogeneous ion channel dysfunction has been reported in sperm from infertile men, the causes of which are unknown. Similarly, the nature of the functional impairment of affected patient sperm remains elusive. There are no reports of studies of Hv1 in human sperm from infertile men. WIDER IMPLICATIONS Recent studies using sperm from infertile men have given new insight and critical evidence supporting the supposition that calcium and potassium conductances are essential for human fertility. However, it should be highlighted that many fundamental questions remain regarding the nature of molecular and functional defects in sperm with dysfunctional ion channels. The development and application of advanced technologies remains a necessity to progress basic and clinical research in this area, with the aim of providing effective screening methodologies to identify and develop treatments for affected men in order to help prevent failed ART cycles. Conversely, development of drugs that block calcium and/or potassium conductances in sperm is a plausible strategy for producing sperm-specific contraceptives.
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Affiliation(s)
- Sean G Brown
- School of Applied Sciences, Abertay University, Dundee DD11HG, UK
| | | | - Christopher L R Barratt
- Systems Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD19SY, UK
| | - Sarah J Martins da Silva
- Systems Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD19SY, UK
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16
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Wang S, Duan Y, Yan Y, Adar C, Braslavsky I, Chen B, Huang T, Qiu S, Li X, Inglis BM, Ji W, Si W. Improvement of sperm cryo-survival of cynomolgus macaque (Macaca fascicularis) by commercial egg-yolk-free freezing medium with type III antifreeze protein. Anim Reprod Sci 2019; 210:106177. [PMID: 31635783 DOI: 10.1016/j.anireprosci.2019.106177] [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] [Received: 03/14/2019] [Revised: 08/24/2019] [Accepted: 09/04/2019] [Indexed: 11/26/2022]
Abstract
When nonhuman primate sperm undergoes cryopreservation in an egg yolk medium there is an increased risk that the egg yolk might adversely affect the sperm due to containing of avian pathogens. Although commercial egg-yolk-free medium for human sperm cryopreservation has been used for macaque sperm, the cryo-survival remains less than optimal. The present study, therefore, was conducted to determine the optimal concentration of antifreeze protein (AFP) III supplemented in a commercial egg-yolk-free medium for cynomolgus macaque (Macaca fascicularis) sperm cryo-survival. The function of frozen-thawed sperm was evaluated by post-thaw sperm motility, acrosome integrity, and mitochondrial function. Results indicate that the sperm motilities were greater when 0.1, 1, and 10 μg/ml of AFP III were supplemented into the sperm freezing medium (P < 0.05). In addition, the mitochondrial membrane potential was greater in the sperm cryopreserved with the medium that was supplemented with 0.1 μg/ml of AFP III (P < 0.05). The addition of AFP III at any of the concentrations, however, did not have any cryoprotection effect on the sperm acrosome, and the greatest concentrations of AFP III at 100 and 200 μg/ml had detrimental effects on acrosomal integrity (P < 0.05). Results of the present study indicated the methods used are effective for the cryopreservation of cynomolgus monkey sperm while reducing associated health risks due to avian pathogens being present in egg yolk-based extenders.
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Affiliation(s)
- Shengnan Wang
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, Yunnan, China
| | - Yanchao Duan
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, Yunnan, China
| | - Yaping Yan
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, Yunnan, China
| | - Chen Adar
- Institute of Biochemistry, Food Science, and Nutrition, Robert H. Smith Faculty of Agriculture, Food, and Environment, & Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - Ido Braslavsky
- Institute of Biochemistry, Food Science, and Nutrition, Robert H. Smith Faculty of Agriculture, Food, and Environment, & Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - Bingbing Chen
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, Yunnan, China
| | - Tianzhuang Huang
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, Yunnan, China
| | - Shuai Qiu
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, Yunnan, China
| | - Xi Li
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, Yunnan, China
| | - Briauna Marie Inglis
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, Yunnan, China
| | - Weizhi Ji
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, Yunnan, China
| | - Wei Si
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, Yunnan, China.
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Kinoshita-Terauchi N, Shiba K, Terauchi M, Romero F, Ramírez-Gómez HV, Yoshida M, Motomura T, Kawai H, Nishigaki T. High potassium seawater inhibits ascidian sperm chemotaxis, but does not affect the male gamete chemotaxis of a brown alga. ZYGOTE 2019; 27:225-231. [PMID: 31317854 DOI: 10.1017/s0967199419000224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Male gamete chemotaxis towards the female gamete is a general strategy to facilitate the sexual reproduction in many marine eukaryotes. Biochemical studies of chemoattractants for male gametes of brown algae have advanced in the 1970s and 1980s, but the molecular mechanism of male gamete responses to the attractants remains elusive. In sea urchin, a K+ channel called the tetraKCNG channel plays a fundamental role in sperm chemotaxis and inhibition of K+ efflux through this channel by high K+ seawater blocks almost all cell responses to the chemoattractant. This signalling mechanism could be conserved in marine invertebrates as tetraKCNG channels are conserved in the marine invertebrates that exhibit sperm chemotaxis. We confirmed that high K+ seawater also inhibited sperm chemotaxis in ascidian, Ciona intestinalis (robusta), in this study. Conversely, the male gamete chemotaxis towards the female gamete of a brown alga, Mutimo cylindricus, was preserved even in high K+ seawater. This result indicates that none of the K+ channels is essential for male gamete chemotaxis in the brown alga, suggesting that the signalling mechanism for chemotaxis in this brown alga is quite different from that of marine invertebrates. Correlated to this result, we revealed that the channels previously proposed as homologues of tetraKCNG in brown algae have a distinct domain composition from that of the tetraKCNG. Namely, one of them possesses two repeats of the six transmembrane segments (diKCNG) instead of four. The structural analysis suggests that diKCNG is a cyclic nucleotide-modulated and/or voltage-gated K+ channel.
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Affiliation(s)
- Nana Kinoshita-Terauchi
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
- Shimoda Marine Research Center, University of Tsukuba, 5-10-1 Shimoda City, Shizuoka 415-0025, Japan
| | - Kogiku Shiba
- Shimoda Marine Research Center, University of Tsukuba, 5-10-1 Shimoda City, Shizuoka 415-0025, Japan
- Misaki Marine Biological Station, Graduate School of Science, University of Tokyo, Miura, Kanagawa 238-0225, Japan
| | - Makoto Terauchi
- Kobe University Research Center for Inland Seas, Rokkodai, Kobe 657-8501, Japan
- Center for Genome Informatics, Joint Support-Center for Data Science Research, Research Organization of Information and Systems, Mishima, Shizuoka 411-8540, Japan
| | - Francisco Romero
- Institute of Biotechnology, National Autonomous University of Mexico (IBT-UNAM), Av. Universidad 2001, Col. Chamilpa, Cuernavaca, Mor. 62210, Mexico
| | - Héctor Vincente Ramírez-Gómez
- Institute of Biotechnology, National Autonomous University of Mexico (IBT-UNAM), Av. Universidad 2001, Col. Chamilpa, Cuernavaca, Mor. 62210, Mexico
| | - Manabu Yoshida
- Misaki Marine Biological Station, Graduate School of Science, University of Tokyo, Miura, Kanagawa 238-0225, Japan
| | - Taizo Motomura
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran 051-0013, Hokkaido, Japan
| | - Hiroshi Kawai
- Kobe University Research Center for Inland Seas, Rokkodai, Kobe 657-8501, Japan
| | - Takuya Nishigaki
- Institute of Biotechnology, National Autonomous University of Mexico (IBT-UNAM), Av. Universidad 2001, Col. Chamilpa, Cuernavaca, Mor. 62210, Mexico
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Mundt N, Spehr M, Lishko PV. TRPV4 is the temperature-sensitive ion channel of human sperm. eLife 2018; 7:35853. [PMID: 29963982 PMCID: PMC6051745 DOI: 10.7554/elife.35853] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Accepted: 06/30/2018] [Indexed: 12/15/2022] Open
Abstract
Ion channels control the ability of human sperm to fertilize the egg by triggering hyperactivated motility, which is regulated by membrane potential, intracellular pH, and cytosolic calcium. Previous studies unraveled three essential ion channels that regulate these parameters: (1) the Ca2+ channel CatSper, (2) the K+ channel KSper, and (3) the H+ channel Hv1. However, the molecular identity of the sperm Na+ conductance that mediates initial membrane depolarization and, thus, triggers downstream signaling events is yet to be defined. Here, we functionally characterize DSper, the Depolarizing Channel of Sperm, as the temperature-activated channel TRPV4. It is functionally expressed at both mRNA and protein levels, while other temperature-sensitive TRPV channels are not functional in human sperm. DSper currents are activated by warm temperatures and mediate cation conductance, that shares a pharmacological profile reminiscent of TRPV4. Together, these results suggest that TRPV4 activation triggers initial membrane depolarization, facilitating both CatSper and Hv1 gating and, consequently, sperm hyperactivation.
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Affiliation(s)
- Nadine Mundt
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States.,Department of Chemosensation, Institute for Biology II, RWTH Aachen University, Aachen, Germany
| | - Marc Spehr
- Department of Chemosensation, Institute for Biology II, RWTH Aachen University, Aachen, Germany
| | - Polina V Lishko
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
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Ferreira G, Costa C, Bassaizteguy V, Santos M, Cardozo R, Montes J, Settineri R, Nicolson GL. Incubation of human sperm with micelles made from glycerophospholipid mixtures increases sperm motility and resistance to oxidative stress. PLoS One 2018; 13:e0197897. [PMID: 29856778 PMCID: PMC5984032 DOI: 10.1371/journal.pone.0197897] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 05/10/2018] [Indexed: 12/31/2022] Open
Abstract
Membrane integrity is essential in maintaining sperm viability, signaling, and motility, which are essential for fertilization. Sperm are highly susceptible to oxidative stress, as they are rich in sensitive polyunsaturated fatty acids (PUFA), and are unable to synthesize and repair many essential membrane constituents. Because of this, sperm cellular membranes are important targets of this process. Membrane Lipid Replacement (MLR) with glycerophospholipid mixtures (GPL) has been shown to ameliorate oxidative stress in cells, restore their cellular membranes, and prevent loss of function. Therefore, we tested the effects of MLR on sperm by tracking and monitoring GPL incorporation into their membrane systems and studying their effects on sperm motility and viability under different experimental conditions. Incubation of sperm with mixtures of exogenous, unoxidized GPL results in their incorporation into sperm membranes, as shown by the use of fluorescent dyes attached to GPL. The percent overall (total) sperm motility was increased from 52±2.5% to 68±1.34% after adding GPL to the incubation media, and overall sperm motility was recovered from 7±2% after H2O2 treatment to 58±2.5%)(n = 8, p<0.01) by the incorporation of GPL into sperm membranes. When sperm were exposed to H2O2, the mitochondrial inner membrane potential (MIMP), monitored using the MIMP tracker dye JC-1 in flow cytometry, diminished, whereas the addition of GPL prevented the decrease in MIMP. Confocal microscopy with Rhodamine-123 and JC-1 confirmed the mitochondrial localization of the dyes. We conclude that incubation of human sperm with glycerolphospholipids into the membranes of sperm improves sperm viability, motility, and resistance to oxidizing agents like H2O2. This suggests that human sperm might be useful to test innovative new treatments like MLR, since such treatments could improve fertility when it is adversely affected by increased oxidative stress.
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Affiliation(s)
- Gonzalo Ferreira
- Departamento de Biofísica, Laboratorio de Canales Iónicos y Señalización Celular, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Carlos Costa
- Departamento de Biofísica, Laboratorio de Canales Iónicos y Señalización Celular, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Verónica Bassaizteguy
- Departamento de Biofísica, Laboratorio de Canales Iónicos y Señalización Celular, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Marcelo Santos
- Departamento de Biofísica, Laboratorio de Canales Iónicos y Señalización Celular, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Romina Cardozo
- Departamento de Biofísica, Laboratorio de Canales Iónicos y Señalización Celular, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | | | - Robert Settineri
- Sierra Productions Research, LLC, Irvine, California, United States of America
| | - Garth L. Nicolson
- Dept. of Molecular Pathology, The Institute for Molecular Medicine, Huntington Beach, California, United States of America
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Liu SW, Li Y, Zou LL, Guan YT, Peng S, Zheng LX, Deng SM, Zhu LY, Wang LW, Chen LX. Chloride channels are involved in sperm motility and are downregulated in spermatozoa from patients with asthenozoospermia. Asian J Androl 2018; 19:418-424. [PMID: 27270342 PMCID: PMC5507086 DOI: 10.4103/1008-682x.181816] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Human spermatozoa encounter an osmotic decrease from 330 to 290 mOsm l−1 when passing through the female reproductive tract. We aimed to evaluate the role of chloride channels in volume regulation and sperm motility from patients with asthenozoospermia. Spermatozoa were purified using Percoll density gradients. Sperm volume was measured as the forward scatter signal using flow cytometry. Sperm motility was analyzed using computer-aided sperm analysis (CASA). When transferred from an isotonic solution (330 mOsm l−1) to a hypotonic solution (290 mOsm l−1), cell volume was not changed in spermatozoa from normozoospermic men; but increased in those from asthenozoospermic samples. The addition of the chloride channel blockers, 4,4′-diisothiocyanatostilbene-2,2′- isulfonic acid (DIDS) or 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) to the hypotonic solution caused the normal spermatozoa to swell but did not increase the volume of those from the asthenozoospermic semen. DIDS and NPPB decreased sperm motility in both sets of semen samples. The inhibitory effect of NPPB on normal sperm motility was much stronger than on spermatozoa from the asthenozoospermic samples. Both sperm types expressed ClC-3 chloride channels, but the expression levels in the asthenozoospermic samples were much lower, especially in the neck and mid-piece areas. Spermatozoa from men with asthenozoospermia demonstrated lower volume regulating capacity, mobility, and ClC-3 expression levels (especially in the neck) than did normal spermatozoa. Thus, chloride channels play important roles in the regulation of sperm volume and motility and are downregulated in cases of asthenozoospermia.
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Affiliation(s)
- Shan-Wen Liu
- Department of Pharmacology, Medical College, Jinan University, Guangzhou, China.,Department of Pathology and Pathophysiology, Medical College, Jinan University, Guangzhou, China
| | - Yuan Li
- Department of Pathology and Pathophysiology, Medical College, Jinan University, Guangzhou, China.,Department of Physiology, Medical College, Jinan University, Guangzhou, China
| | - Li-Li Zou
- Department of Physiology, Medical College, Jinan University, Guangzhou, China
| | - Yu-Tao Guan
- Department of Pharmacology, Medical College, Jinan University, Guangzhou, China.,Department of Pathology and Pathophysiology, Medical College, Jinan University, Guangzhou, China
| | - Shuang Peng
- Department of Pathology and Pathophysiology, Medical College, Jinan University, Guangzhou, China.,Department of Physiology, Medical College, Jinan University, Guangzhou, China
| | - Li-Xin Zheng
- Male Reproductive Center, Family Planning Special Hospital of Guangdong, Guangzhou, China
| | - Shun-Mei Deng
- Male Reproductive Center, Family Planning Special Hospital of Guangdong, Guangzhou, China
| | - Lin-Yan Zhu
- Department of Pharmacology, Medical College, Jinan University, Guangzhou, China
| | - Li-Wei Wang
- Department of Pathology and Pathophysiology, Medical College, Jinan University, Guangzhou, China
| | - Li-Xin Chen
- Department of Pharmacology, Medical College, Jinan University, Guangzhou, China
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Cordero-Martínez J, Reyes-Miguel T, Rodríguez-Páez L, Garduño-Siciliano L, Maldonado-García D, Roa-Espitia AL, Hernández-González EO. TMEM16A inhibition impedes capacitation and acquisition of hyperactivated motility in guinea pig sperm. J Cell Biochem 2018; 119:5944-5959. [PMID: 29600587 DOI: 10.1002/jcb.26789] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 02/12/2018] [Indexed: 11/12/2022]
Abstract
Ca2+ -activated Cl- channels (CaCCs) are anionic channels that regulate many important physiological functions associated with chloride and calcium flux in some somatic cells. The molecular identity of CaCCs was revealed to be TMEM16A and TMEM16B (also known as Anoctamin or ANO1 and ANO2, respectively) in all eukaryotes. A recent study suggests the presence of TMEM16A in human sperm and a relationship with the rhZP-induced acrosome reaction. However, to the best of our knowledge, little is known about the role of TMEM16A in other spermatic processes such as capacitation or motility. In this study, we evaluated the effects of two TMEM16A antagonists on capacitation, acrosome reaction, and motility in guinea pig sperm; these antagonists were T16Ainh-A01, belonging to a second generation of potent antagonists of TMEM16A, and niflumic acid (NFA), a well-known antagonist of TMEM16A (CaCCs). First of all, we confirmed that the absence of Cl- in the capacitation medium changes motility parameters, capacitation, and the progesterone-induced acrosome reaction. Using a specific antibody, TMEM16A was found as a protein band of ∼120 kDa, which localization was in the apical crest of the acrosome and the middle piece of the flagellum. Inhibition of TMEM16A by T16Ainh-A01 affected sperm physiology by reducing capacitation, blocking the progesterone-induced acrosome reaction under optimal capacitation conditions, inhibiting progressive motility, and the acquisition of hyperactivated motility, diminishing [Ca2+ ]i, and increasing [Cl- ]i. These changes in sperm kinematic parameters provide new evidence of the important role played by TMEM16A in the production of sperm capable of fertilizing oocytes.
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Affiliation(s)
- Joaquín Cordero-Martínez
- Departamento de Biología Celular, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional. Av. Instituto Politécnico Nacional, San Pedro Zacatenco, Del. Gustavo A. Madero, México City, Mexico.,Departamento de Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional. Prolongación Manuel Carpio y Plan de Ayala s/n Col, Santo Tomás, Del. Miguel Hidalgo, México City, Mexico
| | - Tania Reyes-Miguel
- Departamento de Biología Celular, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional. Av. Instituto Politécnico Nacional, San Pedro Zacatenco, Del. Gustavo A. Madero, México City, Mexico
| | - Lorena Rodríguez-Páez
- Departamento de Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional. Prolongación Manuel Carpio y Plan de Ayala s/n Col, Santo Tomás, Del. Miguel Hidalgo, México City, Mexico
| | - Leticia Garduño-Siciliano
- Laboratorio de Toxicología de Productos Naturales. Departamento de Farmacia, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional. Prol. Av. Wilfrido Massieu s/n, esq. Manuel L. Stampa, Col. Unidad Profesional Adolfo López Mateos, Del. Gustavo A. Madero, México City, Mexico
| | - Deneb Maldonado-García
- Departamento de Biología Celular, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional. Av. Instituto Politécnico Nacional, San Pedro Zacatenco, Del. Gustavo A. Madero, México City, Mexico
| | - Ana L Roa-Espitia
- Departamento de Biología Celular, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional. Av. Instituto Politécnico Nacional, San Pedro Zacatenco, Del. Gustavo A. Madero, México City, Mexico
| | - Enrique O Hernández-González
- Departamento de Biología Celular, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional. Av. Instituto Politécnico Nacional, San Pedro Zacatenco, Del. Gustavo A. Madero, México City, Mexico
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Carkci S, Etem EO, Ozaydin S, Karakeci A, Tektemur A, Ozan T, Orhan I. Ion channel gene expressions in infertile men: A case-control study. Int J Reprod Biomed 2017; 15:749-756. [PMID: 29492471 PMCID: PMC5816234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Infertility is described as not receiving pregnancy despite unprotected and regular sexual intercourse in a 1 yr period. It is detected by 15% of the couples. Male and female factor in the etiology may be detected in similar rates. OBJECTIVE The present study aims to investigate ion channel gene expression in semen samples of infertile male compared with fertile men. MATERIALS AND METHODS A total of 150 men who applied to the urology clinic due to infertility were divided into five equal groups: asthenozoospermia, oligozoospermia, oligoasthenoteratozoospermia, teratozoospermia, and normozoospermia (control). All paticipants were evaluated with Cation Channel Spermia (CatSper) 1, 2, 3, 4, Proton Voltage Gated Ion Channel1 (Hv1), Potassium Channel Subfamily U1 (KCNU1), and transmembrane protein (TMEM16A) gene expression in semen samples. RESULTS "CatSper1, 4, HV1, KCNU1, and TMEM16A gene expression were detected higher in the oligozoospermia group compared to the controls. CatSper1, 2, 3, 4, KCNU1, and TMEM16A gene expression in the asthenozoospermia group and CatSper1, 2, 3, 4, KCNU1, and TMEM16A gene expression in the teratozoospermia group were detected lower compared to the controls. CatSper1, 4, HV1, and TMEM16A gen expression were higher in the oligoasthenoteratozoospermia men than the controls while CatSper3 gen expression was detected as lower." CONCLUSION It was detected that these ion channels have an effect on sperm progressive motility and morphology. It may be considered that mutations in these ion channels may result in infertility.
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Affiliation(s)
- Serkan Carkci
- Department of Urology, Faculty of Medicine, Firat University, Elazig, Turkey.
| | - Ebru Onalan Etem
- Department of Medical Biology, Faculty of Medicine, Firat University, Elazig, Turkey.
| | - Seda Ozaydin
- Department of Medical Biology, Faculty of Medicine, Firat University, Elazig, Turkey.
| | - Ahmet Karakeci
- Department of Urology, Faculty of Medicine, Firat University, Elazig, Turkey.
| | - Ahmet Tektemur
- Department of Medical Biology, Faculty of Medicine, Firat University, Elazig, Turkey.
| | - Tunc Ozan
- Department of Urology, Faculty of Medicine, Firat University, Elazig, Turkey.
| | - Irfan Orhan
- Department of Urology, Faculty of Medicine, Firat University, Elazig, Turkey.
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Carkci S, Onalan Etem E, Ozaydin S, Karakeci A, Tektemur A, Ozan T, Orhan I. Ion channel gene expressions in infertile men: A case-control study. Int J Reprod Biomed 2017. [DOI: 10.29252/ijrm.15.12.749] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
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Beltrán C, Treviño CL, Mata-Martínez E, Chávez JC, Sánchez-Cárdenas C, Baker M, Darszon A. Role of Ion Channels in the Sperm Acrosome Reaction. SPERM ACROSOME BIOGENESIS AND FUNCTION DURING FERTILIZATION 2016; 220:35-69. [DOI: 10.1007/978-3-319-30567-7_3] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Modulating Ca²⁺ signals: a common theme for TMEM16, Ist2, and TMC. Pflugers Arch 2015; 468:475-90. [PMID: 26700940 DOI: 10.1007/s00424-015-1767-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 11/24/2015] [Accepted: 11/26/2015] [Indexed: 12/21/2022]
Abstract
Since the discovery of TMEM16A (anoctamin 1, ANO1) as Ca(2+)-activated Cl(-) channel, the protein was found to serve different physiological functions, depending on the type of tissue. Subsequent reports on other members of the anoctamin family demonstrated a broad range of yet poorly understood properties. Compromised anoctamin function is causing a wide range of diseases, such as hearing loss (ANO2), bleeding disorder (ANO6), ataxia and dystonia (ANO3, 10), persistent borrelia and mycobacteria infection (ANO10), skeletal syndromes like gnathodiaphyseal dysplasia and limb girdle muscle dystrophy (ANO5), and cancer (ANO1, 6, 7). Animal models demonstrate CF-like airway disease, asthma, and intestinal hyposecretion (ANO1). Although present data indicate that ANO1 is a Ca(2+)-activated Cl(-) channel, it remains unclear whether all anoctamins form plasma membrane-localized or intracellular chloride channels. We find Ca(2+)-activated Cl(-) currents appearing by expression of most anoctamin paralogs, including the Nectria haematococca homologue nhTMEM16 and the yeast homologue Ist2. As recent studies show a role of anoctamins, Ist2, and the related transmembrane channel-like (TMC) proteins for intracellular Ca(2+) signaling, we will discuss the role of these proteins in generating compartmentalized Ca(2+) signals, which may give a hint as to the broad range of cellular functions of anoctamins.
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26
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Williams HL, Mansell S, Alasmari W, Brown SG, Wilson SM, Sutton KA, Miller MR, Lishko PV, Barratt CLR, Publicover SJ, Martins da Silva S. Specific loss of CatSper function is sufficient to compromise fertilizing capacity of human spermatozoa. Hum Reprod 2015; 30:2737-46. [PMID: 26453676 PMCID: PMC4643530 DOI: 10.1093/humrep/dev243] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Accepted: 09/07/2015] [Indexed: 12/26/2022] Open
Abstract
STUDY QUESTION Are significant abnormalities of CatSper function present in IVF patients with normal sperm concentration and motility and if so what is their functional significance for fertilization success? SUMMARY ANSWER Sperm with a near absence of CatSper current failed to respond to activation of CatSper by progesterone and there was fertilization failure at IVF. WHAT IS KNOWN ALREADY In human spermatozoa, Ca2+ influx induced by progesterone is mediated by CatSper, a sperm-specific Ca2+ channel. A suboptimal Ca2+ influx is significantly associated with, and more prevalent in, men with abnormal semen parameters, and is associated with reduced fertilizing capacity. However, abnormalities in CatSper current can only be assessed directly using electrophysiology. There is only one report of a CatSper-deficient man who showed no progesterone potentiated CatSper current. A CatSper 2 genetic abnormality was present but there was no information on the [Ca2+]i response to CatSper activation by progesterone. Additionally, the semen samples had indicating significant abnormalities (oligoasthenoteratozoospermia) multiple suboptimal functional responses in the spermatozoon. As such it cannot be concluded that impaired CatSper function alone causes infertility or that CatSper blockade is a potential safe target for contraception. STUDY DESIGN, SIZE, DURATION Spermatozoa were obtained from donors and subfertile IVF patients attending a hospital assisted reproductive techniques clinic between January 2013 and December 2014. In total 134 IVF patients, 28 normozoospermic donors and 10 patients recalled due to a history of failed/low fertilization at IVF took part in the study. PARTICIPANTS/MATERIALS, SETTING, METHODS Samples were primarily screened using the Ca2+ influx induced by progesterone and, if cell number was sufficient, samples were also assessed by hyperactivation and penetration into viscous media. A defective Ca2+ response to progesterone was defined using the 99% confidence interval from the distribution of response amplitudes in normozoospermic donors. Samples showing a defective Ca2+ response were further examined in order to characterize the potential CatSper abnormalities. In men where there was a consistent and robust failure of calcium signalling, a direct assessment of CatSper function was performed using electrophysiology (patch clamping), and a blood sample was obtained for genetic analysis. MAIN RESULTS AND THE ROLE OF CHANCE A total of 101/102 (99%) IVF patients and 22/23 (96%) donors exhibited a normal Ca2+ response. The mean (±SD) normalized peak response did not differ between donors and IVF patients (2.57 ± 0.68 [n = 34 ejaculates from 23 different donors] versus 2.66 ± 0.68 [n = 102 IVF patients], P = 0.63). In recall patients, 9/10 (90%) showed a normal Ca2+ response. Three men were initially identified with a defective Ca2+ influx. However, only one (Patient 1) had a defective response in repeat semen samples. Electrophysiology experiments on sperm from Patient 1 showed a near absence of CatSper current and exon screening demonstrated no mutations in the coding regions of the CatSper complex. There was no increase in penetration of viscous media when the spermatozoa were stimulated with progesterone and importantly there was failed fertilization at IVF. LIMITATIONS, REASONS FOR CAUTION A key limitation relates to working with a specific functional parameter (Ca2+ influx induced by progesterone) in fresh sperm samples from donors and patients that have limited viability. Therefore, for practical, technical and logistical reasons, some men (∼22% of IVF patients) could not be screened. As such the incidence of significant Ca2+ abnormalities induced by progesterone may be higher than the ∼1% observed here. Additionally, we used a strict definition of a defective Ca2+ influx such that only substantial abnormalities were selected for further study. Furthermore, electrophysiology was only performed on one patient with a robust and repeatable defective calcium response. This man had negligible CatSper current but more subtle abnormalities (e.g. currents present but significantly smaller) may have been present in men with either normal or below normal Ca2+ influx. WIDER IMPLICATIONS OF THE FINDINGS These data add significantly to the understanding of the role of CatSper in human sperm function and its impact on male fertility. Remarkably, these findings provide the first direct evidence that CatSper is a suitable and specific target for human male contraception. STUDY FUNDING/COMPETING INTEREST(S) Initial funding was from NHS Tayside, Infertility Research Trust, TENOVUS, Chief Scientist Office NRS Fellowship, the Wellcome Trust, University of Abertay. The majority of the data were obtained using funding from a MRC project grant (# 4190). The authors declare that there is no conflict of interest. TRIAL REGISTRATION NUMBER Not applicable.
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Affiliation(s)
- Hannah L Williams
- Reproductive and Developmental Biology, Medical School, Ninewells Hospital, University of Dundee, Dundee DD1 9SY, UK Assisted Conception Unit, NHS Tayside, Ninewells Hospital, Dundee DD1 9SY, UK
| | - Steven Mansell
- Reproductive and Developmental Biology, Medical School, Ninewells Hospital, University of Dundee, Dundee DD1 9SY, UK Department of Molecular and Cell Biology, University of California, Berkeley, USA
| | - Wardah Alasmari
- Reproductive and Developmental Biology, Medical School, Ninewells Hospital, University of Dundee, Dundee DD1 9SY, UK
| | | | - Stuart M Wilson
- Reproductive and Developmental Biology, Medical School, Ninewells Hospital, University of Dundee, Dundee DD1 9SY, UK Wolfson Research Institute, School of Medicine, Pharmacy and Health, Queen's Campus, University Of Durham, Stockton on Tees TS17 6BH, UK
| | - Keith A Sutton
- Reproductive and Developmental Biology, Medical School, Ninewells Hospital, University of Dundee, Dundee DD1 9SY, UK
| | - Melissa R Miller
- Department of Molecular and Cell Biology, University of California, Berkeley, USA
| | - Polina V Lishko
- Department of Molecular and Cell Biology, University of California, Berkeley, USA
| | - Christopher L R Barratt
- Reproductive and Developmental Biology, Medical School, Ninewells Hospital, University of Dundee, Dundee DD1 9SY, UK Assisted Conception Unit, NHS Tayside, Ninewells Hospital, Dundee DD1 9SY, UK
| | | | - Sarah Martins da Silva
- Reproductive and Developmental Biology, Medical School, Ninewells Hospital, University of Dundee, Dundee DD1 9SY, UK Assisted Conception Unit, NHS Tayside, Ninewells Hospital, Dundee DD1 9SY, UK
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Miller MR, Mansell SA, Meyers SA, Lishko PV. Flagellar ion channels of sperm: similarities and differences between species. Cell Calcium 2015; 58:105-13. [DOI: 10.1016/j.ceca.2014.10.009] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 10/16/2014] [Accepted: 10/20/2014] [Indexed: 10/24/2022]
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Bradley E, Fedigan S, Webb T, Hollywood MA, Thornbury KD, McHale NG, Sergeant GP. Pharmacological characterization of TMEM16A currents. Channels (Austin) 2015; 8:308-20. [PMID: 24642630 DOI: 10.4161/chan.28065] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Recent studies have shown that transmembrane protein 16 A (TMEM16A) is a subunit of calcium-activated chloride channels (CACCs). Pharmacological agents have been used to probe the functional role of CACCs, however their effect on TMEM16A currents has not been systematically investigated. In the present study, we characterized the voltage and concentration-dependent effects of 2 traditional CACC inhibitors (niflumic acid and anthracene-9-carboxcylic acid) and 2 novel CACC / TMEM16A inhibitors (CACC(inh)A01 and T16A(inh)A01) on TMEM16A currents. The whole cell patch clamp technique was used to record TMEM16A currents from HE K 293 cells that stably expressed human TMEM16A. Niflumic acid, A-9-C, CACC(inh)A01 and T16A(inh)A01 inhibited TMEM16A currents with IC50 values of 12, 58, 1.7 and 1.5 μM, respectively, however, A-9-C and niflumic acid were less efficacious at negative membrane potentials. A-9-C and niflumic acid reduced the rate of TMEM16A tail current deactivation at negative membrane potentials and A-9-C (1 mM) enhanced peak TMEM16A tail current amplitude. In contrast, the inhibitory effects of CACC(inh)A01 and T16A(inh)A01 were independent of voltage and they did not prolong the rate of TMEM16A tail current deactivation. The effects of niflumic acid and A-9-C on TMEM16A currents were similar to previous observations on CACCs in vascular smooth muscle, strengthening the hypothesis that they are encoded by TMEM16A. However, CACC(inh)A01 and T16A(inh)A01 were more potent inhibitors of TMEM16A channels and their effects were not diminished at negative membrane potentials making them attractive candidates to interrogate the functional role of TMEM16A channels in future studies.
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Leblanc N, Forrest AS, Ayon RJ, Wiwchar M, Angermann JE, Pritchard HAT, Singer CA, Valencik ML, Britton F, Greenwood IA. Molecular and functional significance of Ca(2+)-activated Cl(-) channels in pulmonary arterial smooth muscle. Pulm Circ 2015; 5:244-68. [PMID: 26064450 DOI: 10.1086/680189] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 07/22/2014] [Indexed: 12/31/2022] Open
Abstract
Increased peripheral resistance of small distal pulmonary arteries is a hallmark signature of pulmonary hypertension (PH) and is believed to be the consequence of enhanced vasoconstriction to agonists, thickening of the arterial wall due to remodeling, and increased thrombosis. The elevation in arterial tone in PH is attributable, at least in part, to smooth muscle cells of PH patients being more depolarized and displaying higher intracellular Ca(2+) levels than cells from normal subjects. It is now clear that downregulation of voltage-dependent K(+) channels (e.g., Kv1.5) and increased expression and activity of voltage-dependent (Cav1.2) and voltage-independent (e.g., canonical and vanilloid transient receptor potential [TRPC and TRPV]) Ca(2+) channels play an important role in the functional remodeling of pulmonary arteries in PH. This review focuses on an anion-permeable channel that is now considered a novel excitatory mechanism in the systemic and pulmonary circulations. It is permeable to Cl(-) and is activated by a rise in intracellular Ca(2+) concentration (Ca(2+)-activated Cl(-) channel, or CaCC). The first section outlines the biophysical and pharmacological properties of the channel and ends with a description of the molecular candidate genes postulated to encode for CaCCs, with particular emphasis on the bestrophin and the newly discovered TMEM16 and anoctamin families of genes. The second section provides a review of the various sources of Ca(2+) activating CaCCs, which include stimulation by mobilization from intracellular Ca(2+) stores and Ca(2+) entry through voltage-dependent and voltage-independent Ca(2+) channels. The third and final section summarizes recent findings that suggest a potentially important role for CaCCs and the gene TMEM16A in PH.
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Affiliation(s)
- Normand Leblanc
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Abigail S Forrest
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Ramon J Ayon
- Department of Medicine, University of Illinois, Chicago, Illinois, USA
| | - Michael Wiwchar
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Jeff E Angermann
- School of Community Health Sciences, University of Nevada, Reno, Nevada, USA
| | - Harry A T Pritchard
- Vascular Biology Research Centre, Institute of Cardiovascular and Cell Sciences, St. George's University of London, London, United Kingdom
| | - Cherie A Singer
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Maria L Valencik
- Department of Biochemistry and Molecular Biology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Fiona Britton
- Department of Physiology, School of Medical Sciences, University of New South Wales, Sydney, Australia
| | - Iain A Greenwood
- Vascular Biology Research Centre, Institute of Cardiovascular and Cell Sciences, St. George's University of London, London, United Kingdom
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Sun M, Sui Y, Li L, Su W, Hao F, Zhu Q, Di W, Gao H, Ma T. Anoctamin 1 calcium-activated chloride channel downregulates estrogen production in mouse ovarian granulosa cells. Endocrinology 2014; 155:2787-96. [PMID: 24823391 DOI: 10.1210/en.2013-2155] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Calcium-dependent chloride conductances have been described in chicken and human granulosa cells (GCs) and may be involved in steroidogenesis. However, the molecular identities of corresponding chloride channels remain unknown. The purpose of this study was to explore the expression and function of the Anoctamin 1 (ANO1) calcium-activated chloride channel (CaCC) in mouse ovary. ANO1 mRNA and protein expression was identified in mouse ovary GCs by RT-PCR, immunoblot, and immunostaining. Patch-clamp analysis on freshly isolated GCs identified an outwardly rectifying Ca(2+)-activated Cl(-) current that was completely blocked by a selective ANO1 inhibitor T16Ainh-A01. Knockdown of ANO1 mRNA or incubation with a selective inhibitor T16Ainh-A01 enhanced estradiol production, whereas a selective ANO1 activator Eact significantly inhibited estradiol production in primary cultured GCs. The ANO1 expression or activation increases the phosphorylation of ERK1/2 and decreases aromatase expression. The ANO1 expression level is remarkably higher at the proestrous and estrous stages in the estrous cycle. In vivo study indicated a profound induction of ANO1 expression in ovarian GCs by pregnant mare serum gonadotropin (PMSG) that can be further augmented by hCG treatment, suggesting that both FSH and LH may upregulate ANO1 expression at the proestrous and estrous stages. ANO1 expression was remarkably reduced in DHEA-induced PCOS ovary. These data identified for the first time the expression of ANO1 Ca(2+) activated Cl(-) channel in mouse ovarian GCs and determined its negative regulation on estrogen production possibly through MEK-ERK signaling cascade. The present study provided new insights into the molecular mechanisms for the regulation of folliculogenesis and ovulation.
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Affiliation(s)
- Meiyan Sun
- Central Research Laboratory (M.S., Y.S., W.S., Q.Z., W.D., H.G., T.M.), Jilin University Bethune Second Hospital, Changchun, 130041 Peoples Republic of China; College of Basic Medical Sciences (T.M.), Dalian Medical University, Dalian, 116044 Peoples Republic of China; Department of Laboratory Medicine (M.S., F.H.), Jilin Medical College, Jilin, 132013 Peoples Republic of China; and Department of Cell Biology (L.L.), Liaoning Medical University, Liaoning, 121001 Peoples Republic of China
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López-González I, Torres-Rodríguez P, Sánchez-Carranza O, Solís-López A, Santi CM, Darszon A, Treviño CL. Membrane hyperpolarization during human sperm capacitation. Mol Hum Reprod 2014; 20:619-29. [PMID: 24737063 DOI: 10.1093/molehr/gau029] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Sperm capacitation is a complex and indispensable physiological process that spermatozoa must undergo in order to acquire fertilization capability. Spermatozoa from several mammalian species, including mice, exhibit a capacitation-associated plasma membrane hyperpolarization, which is necessary for the acrosome reaction to occur. Despite its importance, this hyperpolarization event has not been adequately examined in human sperm. In this report we used flow cytometry to show that a subpopulation of human sperm indeed undergo a plasma membrane hyperpolarization upon in vitro capacitation. This hyperpolarization correlated with two other well-characterized capacitation parameters, namely an increase in intracellular pH and Ca(2+) concentration, measured also by flow cytometry. We found that sperm membrane hyperpolarization was completely abolished in the presence of a high external K(+) concentration (60 mM), indicating the participation of K(+) channels. In order to identify, which of the potential K(+) channels were involved in this hyperpolarization, we used different K(+) channel inhibitors including charybdotoxin, slotoxin and iberiotoxin (which target Slo1) and clofilium (a more specific blocker for Slo3). All these K(+) channel antagonists inhibited membrane hyperpolarization to a similar extent, suggesting that both members of the Slo family may potentially participate. Two very recent papers recorded K(+) currents in human sperm electrophysiologically, with some contradictory results. In the present work, we show through immunoblotting that Slo3 channels are present in the human sperm membrane. In addition, we found that human Slo3 channels expressed in CHO cells were sensitive to clofilium (50 μM). Considered altogether, our data indicate that Slo1 and Slo3 could share the preponderant role in the capacitation-associated hyperpolarization of human sperm in contrast to what has been previously reported for mouse sperm, where Slo3 channels are the main contributors to the hyperpolarization event.
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Affiliation(s)
- I López-González
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62210, México
| | - P Torres-Rodríguez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62210, México
| | - O Sánchez-Carranza
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62210, México
| | - A Solís-López
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62210, México
| | - C M Santi
- Department of Anatomy and Neurobiology, Washington University School of Medicine, 660 S Euclid Ave, St. Louis, MO 63110, USA
| | - A Darszon
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62210, México
| | - C L Treviño
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62210, México
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Abstract
TMEM16 proteins, also known as anoctamins, are involved in a variety of functions that include ion transport, phospholipid scrambling, and regulation of other membrane proteins. The first two members of the family, TMEM16A (anoctamin-1, ANO1) and TMEM16B (anoctamin-2, ANO2), function as Ca2+-activated Cl- channels (CaCCs), a type of ion channel that plays important functions such as transepithelial ion transport, smooth muscle contraction, olfaction, phototransduction, nociception, and control of neuronal excitability. Genetic ablation of TMEM16A in mice causes impairment of epithelial Cl- secretion, tracheal abnormalities, and block of gastrointestinal peristalsis. TMEM16A is directly regulated by cytosolic Ca2+ as well as indirectly by its interaction with calmodulin. Other members of the anoctamin family, such as TMEM16C, TMEM16D, TMEM16F, TMEM16G, and TMEM16J, may work as phospholipid scramblases and/or ion channels. In particular, TMEM16F (ANO6) is a major contributor to the process of phosphatidylserine translocation from the inner to the outer leaflet of the plasma membrane. Intriguingly, TMEM16F is also associated with the appearance of anion/cation channels activated by very high Ca2+ concentrations. Furthermore, a TMEM16 protein expressed in Aspergillus fumigatus displays both ion channel and lipid scramblase activity. This finding suggests that dual function is an ancestral characteristic of TMEM16 proteins and that some members, such as TMEM16A and TMEM16B, have evolved to a pure channel function. Mutations in anoctamin genes (ANO3, ANO5, ANO6, and ANO10) cause various genetic diseases. These diseases suggest the involvement of anoctamins in a variety of cell functions whose link with ion transport and/or lipid scrambling needs to be clarified.
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Brenker C, Zhou Y, Müller A, Echeverry FA, Trötschel C, Poetsch A, Xia XM, Bönigk W, Lingle CJ, Kaupp UB, Strünker T. The Ca2+-activated K+ current of human sperm is mediated by Slo3. eLife 2014; 3:e01438. [PMID: 24670955 PMCID: PMC3966514 DOI: 10.7554/elife.01438] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Sperm are equipped with a unique set of ion channels that orchestrate fertilization. In mouse sperm, the principal K+ current (IKSper) is carried by the Slo3 channel, which sets the membrane potential (Vm) in a strongly pHi-dependent manner. Here, we show that IKSper in human sperm is activated weakly by pHi and more strongly by Ca2+. Correspondingly, Vm is strongly regulated by Ca2+ and less so by pHi. We find that inhibitors of Slo3 suppress human IKSper, and we identify the Slo3 protein in the flagellum of human sperm. Moreover, heterologously expressed human Slo3, but not mouse Slo3, is activated by Ca2+ rather than by alkaline pHi; current–voltage relations of human Slo3 and human IKSper are similar. We conclude that Slo3 represents the principal K+ channel in human sperm that carries the Ca2+-activated IKSper current. We propose that, in human sperm, the progesterone-evoked Ca2+ influx carried by voltage-gated CatSper channels is limited by Ca2+-controlled hyperpolarization via Slo3. DOI:http://dx.doi.org/10.7554/eLife.01438.001 A sperm that has been ejaculated into the female reproductive tract must complete a number of tasks to pass on its genes to the next generation. First it must travel along a meandering route to encounter an egg, before pushing through a jelly-like coating that surrounds the egg and then, finally, fusing with the egg’s surface membrane. In order to complete these steps and fertilise the egg, a sperm must undergo a process called ‘capacitation’. This process, and a variety of other sperm functions, involves the controlled flux of positive ions into and out of the sperm via specific ion channels that are located in the cell membrane. The properties of the ion channels that allow protons and calcium ions to move into and out of human sperm are well understood, but less is known about the channels that control the movement of potassium ions. In mice, a channel called Slo3 allows potassium ions to flow out of the sperm and makes the membrane voltage of these cells more negative. Also, in mice, this channel is essential for the sperm to function correctly, and for fertilization. However, in humans, it is unclear if the Slo3 channel is present in sperm and if it performs the same role. Now, Brenker et al. have shown that the flow of potassium ions out of human sperm occurs via the Slo3 channel, and that human Slo3 is responsible for setting the membrane voltage of these cells. However, whereas the mouse Slo3 channel is opened in response to a decrease in the concentration of protons within the sperm (i.e., an increase of the pH inside the cell), human Slo3 is largely controlled by changes in the levels of calcium ions. An increase in the calcium concentration within the cell opens the human Slo3 channel, more than a decrease in the proton concentration does. Altogether, Brenker et al. identify Slo3 as the principal potassium channel in human sperm and reveal more fundamental differences between human sperm and mouse sperm. Thereby, this work further stresses the need to be cautious about using mice as a model of male fertility in humans. DOI:http://dx.doi.org/10.7554/eLife.01438.002
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Affiliation(s)
- Christoph Brenker
- Department of Molecular Sensory Systems, Center of Advanced European Studies and Research, Bonn, Germany
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T-type Ca2+ channels in spermatogenic cells and sperm. Pflugers Arch 2014; 466:819-31. [DOI: 10.1007/s00424-014-1478-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 02/08/2014] [Indexed: 12/14/2022]
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Mansell SA, Publicover SJ, Barratt CLR, Wilson SM. Patch clamp studies of human sperm under physiological ionic conditions reveal three functionally and pharmacologically distinct cation channels. Mol Hum Reprod 2014; 20:392-408. [PMID: 24442342 PMCID: PMC4004083 DOI: 10.1093/molehr/gau003] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Whilst fertilizing capacity depends upon a K+ conductance (GK) that allows the spermatozoon membrane potential (Vm) to be held at a negative value, the characteristics of this conductance in human sperm are virtually unknown. We therefore studied the biophysical/pharmacological properties of the K+ conductance in spermatozoa from normal donors held under voltage/current clamp in the whole cell recording configuration. Our standard recording conditions were designed to maintain quasi-physiological, Na+, K+ and Cl− gradients. Experiments that explored the effects of ionic substitution/ion channel blockers upon membrane current/potential showed that resting Vm was dependent upon a hyperpolarizing K+ current that flowed via channels that displayed only weak voltage dependence and limited (∼7-fold) K+ versus Na+ selectivity. This conductance was blocked by quinidine (0.3 mM), bupivacaine (3 mM) and clofilium (50 µM), NNC55-0396 (2 µM) and mibefradil (30 µM), but not by 4-aminopyridine (2 mM, 4-AP). Progesterone had no effect upon the hyperpolarizing K+ current. Repolarization after a test depolarization consistently evoked a transient inward ‘tail current’ (ITail) that flowed via a second population of ion channels with poor (∼3-fold) K+ versus Na+ selectivity. The activity of these channels was increased by quinidine, 4-AP and progesterone. Vm in human sperm is therefore dependent upon a hyperpolarizing K+ current that flows via channels that most closely resemble those encoded by Slo3. Although 0.5 µM progesterone had no effect upon these channels, this hormone did activate the pharmacologically distinct channels that mediate ITail. In conclusion, this study reveals three functionally and pharmacologically distinct cation channels: Ik, ITail, ICatSper.
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Affiliation(s)
- S A Mansell
- Medical Research Institute, College of Medicine, Dentistry and Nursing, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9S, UK
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Yu K, Zhu J, Qu Z, Cui YY, Hartzell HC. Activation of the Ano1 (TMEM16A) chloride channel by calcium is not mediated by calmodulin. ACTA ACUST UNITED AC 2014; 143:253-67. [PMID: 24420770 PMCID: PMC4001774 DOI: 10.1085/jgp.201311047] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Calcium-mediated activation of the TMEM16A chloride channel does not depend on changes in phosphorylation status or the calcium-binding protein calmodulin. The Ca2+-activated Cl channel anoctamin-1 (Ano1; Tmem16A) plays a variety of physiological roles, including epithelial fluid secretion. Ano1 is activated by increases in intracellular Ca2+, but there is uncertainty whether Ca2+ binds directly to Ano1 or whether phosphorylation or additional Ca2+-binding subunits like calmodulin (CaM) are required. Here we show that CaM is not necessary for activation of Ano1 by Ca2+ for the following reasons. (a) Exogenous CaM has no effect on Ano1 currents in inside-out excised patches. (b) Overexpression of Ca2+-insensitive mutants of CaM have no effect on Ano1 currents, whereas they eliminate the current mediated by the small-conductance Ca2+-activated K+ (SK2) channel. (c) Ano1 does not coimmunoprecipitate with CaM, whereas SK2 does. Furthermore, Ano1 binds very weakly to CaM in pull-down assays. (d) Ano1 is activated in excised patches by low concentrations of Ba2+, which does not activate CaM. In addition, we conclude that reversible phosphorylation/dephosphorylation is not required for current activation by Ca2+ because the current can be repeatedly activated in excised patches in the absence of ATP or other high-energy compounds. Although Ano1 is blocked by the CaM inhibitor trifluoperazine (TFP), we propose that TFP inhibits the channel in a CaM-independent manner because TFP does not inhibit Ano1 when applied to the cytoplasmic side of excised patches. These experiments lead us to conclude that CaM is not required for activation of Ano1 by Ca2+. Although CaM is not required for channel opening by Ca2+, work of other investigators suggests that CaM may have effects in modulating the biophysical properties of the channel.
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Affiliation(s)
- Kuai Yu
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322
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37
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Sati L, Cayli S, Delpiano E, Sakkas D, Huszar G. The pattern of tyrosine phosphorylation in human sperm in response to binding to zona pellucida or hyaluronic acid. Reprod Sci 2013; 21:573-81. [PMID: 24077441 DOI: 10.1177/1933719113504467] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In mammalian species, acquisition of sperm fertilization competence is dependent on the phenomenon of sperm capacitation. One of the key elements of capacitation is protein tyrosine phosphorylation (TP) in various sperm membrane regions. In previous studies performed, the pattern of TP was examined in human sperm bound to zona pellucida of oocytes. In the present comparative study, TP patterns upon sperm binding to the zona pellucida or hyaluronic acid (HA) were investigated in spermatozoa arising from the same semen samples. Tyrosine phosphorylation, visualized by immunofluorescence, was localized within the acrosomal cap, equatorial head region, neck, and the principal piece. Tyrosine phosphorylation has increased in a time-related manner as capacitation progressed, and the phosphorylation pattern was identical within the principal piece and neck, regardless of the sperm bound to the zona pellucida or HA. Thus, the data demonstrated that the patterns of sperm activation-related TP were similar regardless of the spermatozoa bound to zona pellucida or HA. Further, sperm with incomplete development, as detected by excess cytoplasmic retention, failed to exhibit TP.
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Affiliation(s)
- Leyla Sati
- 1Department of Histology and Embryology, Akdeniz University School of Medicine, Antalya, Turkey
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Mortimer D, Barratt CLR, Björndahl L, de Jager C, Jequier AM, Muller CH. What should it take to describe a substance or product as 'sperm-safe'. Hum Reprod Update 2013; 19 Suppl 1:i1-45. [PMID: 23552271 DOI: 10.1093/humupd/dmt008] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Male reproductive potential continues to be adversely affected by many environmental, industrial and pharmaceutical toxins. Pre-emptive testing for reproductive toxicological (side-)effects remains limited, or even non-existent. Many products that come into direct contact with spermatozoa lack adequate testing for the absence of adverse effects, and numerous products that are intended for exposure to spermatozoa have only a general assumption of safety based on the absence of evidence of actual harm. Such assumptions can have unfortunate adverse impacts on at-risk individuals (e.g. couples who are trying to conceive), illustrating a clear need for appropriate up-front testing to establish actual 'sperm safety'. METHODS After compiling a list of general areas within the review's scope, relevant literature and other information was obtained from the authors' personal professional libraries and archives, and supplemented as necessary using PubMed and Google searches. Review by co-authors identified and eliminated errors of omission or bias. RESULTS This review provides an overview of the broad range of substances, materials and products that can affect male fertility, especially through sperm fertilizing ability, along with a discussion of practical methods and bioassays for their evaluation. It is concluded that products can only be claimed to be 'sperm-safe' after performing objective, properly designed experimental studies; extrapolation from supposed predicate products or other assumptions cannot be trusted. CONCLUSIONS We call for adopting the precautionary principle, especially when exposure to a product might affect not only a couple's fertility potential but also the health of resulting offspring and perhaps future generations.
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Affiliation(s)
- David Mortimer
- Oozoa Biomedical Inc., Caulfeild Village, West Vancouver, BC, Canada.
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39
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Sondo E, Scudieri P, Tomati V, Caci E, Mazzone A, Farrugia G, Ravazzolo R, Galietta LJV. Non-canonical translation start sites in the TMEM16A chloride channel. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:89-97. [PMID: 23994600 PMCID: PMC3898931 DOI: 10.1016/j.bbamem.2013.08.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 08/13/2013] [Accepted: 08/14/2013] [Indexed: 01/16/2023]
Abstract
TMEM16A is a plasma membrane protein with voltage- and calcium-dependent chloride channel activity. The role of the various TMEM16A domains in expression and function is poorly known. In a previous study, we found that replacing the first ATG of the TMEM16A coding sequence with a nonsense codon (M1X mutation), to force translation from the second ATG localized at position 117, only had minor functional consequences. Therefore, we concluded that this region is dispensable for TMEM16A processing and channel activity. We have now removed the first 116 codons from the TMEM16A coding sequence. Surprisingly, the expression of the resulting mutant, Δ(1–116), resulted in complete loss of activity. We hypothesized that, in the mutant M1X, translation may start at a position before the second ATG, using a non-canonical start codon. Therefore, we placed an HA-epitope at position 89 in the M1X mutant. We found, by western blot analysis, that the HA-epitope can be detected, thus demonstrating that translation starts from an upstream non-ATG codon. We truncated the N-terminus of TMEM16A at different sites while keeping the HA-epitope. We found that stepwise shortening of TMEM16A caused an in parallel stepwise decrease in TMEM16A expression and function. Our results indicate that indeed the N-terminus of TMEM16A is important for its activity. The use of an alternative start codon appears to occur in a naturally-occurring TMEM16A isoform that is particularly expressed in human testis. Future experiments will need to address the role of normal and alternative amino-terminus in TMEM16A structure and function. TMEM16A is a membrane protein with chloride channel activity. Two ATG codons are present at positions 1 and 117 of the TMEM16A coding sequence. Deletion of the first ATG, in contrast to removal of the first 116 codons, does not abolish TMEM16A function. Without the first ATG, TMEM16A translation begins from a non-canonical start codon.
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Affiliation(s)
- Elvira Sondo
- U.O.C. Genetica Medica, Istituto Giannina Gaslini, Genova, Italy
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Zheng LP, Wang HF, Li BM, Zeng XH. Sperm-specific ion channels: targets holding the most potential for male contraceptives in development. Contraception 2013; 88:485-91. [PMID: 23845210 DOI: 10.1016/j.contraception.2013.06.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 06/03/2013] [Accepted: 06/04/2013] [Indexed: 12/27/2022]
Abstract
There is a global need for an ideal method of male contraception. However, the development of male contraceptives has not been well successful. Research on sperm-specific ion channels, especially the recent advance obtained from electrophysiological studies, has emphasized the conception that those channels are targets with the most potential to develop non-hormonal male contraceptives. While summarizing the general options for male contraception, this review focuses on the properties and functions of sperm ion channels together with the attempts of utilizing these channels to develop male contraceptives. We believe that a deeper insight into the signaling and molecular mechanisms by which ion channels regulate sperm functions will pave the way for developing novel male-based contraceptives.
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Affiliation(s)
- Li-Ping Zheng
- Institute of Life Science, Nanchang University, Nanchang 330031, China.
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41
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Battistone MA, Da Ros VG, Salicioni AM, Navarrete FA, Krapf D, Visconti PE, Cuasnicú PS. Functional human sperm capacitation requires both bicarbonate-dependent PKA activation and down-regulation of Ser/Thr phosphatases by Src family kinases. Mol Hum Reprod 2013; 19:570-80. [PMID: 23630234 DOI: 10.1093/molehr/gat033] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
In all mammalian species studied so far, sperm capacitation correlates with an increase in protein tyrosine (Tyr) phosphorylation mediated by a bicarbonate-dependent cAMP/protein kinase A (PKA) pathway. Recent studies in mice revealed, however, that a Src family kinase (SFK)-induced inactivation of serine/threonine (Ser/Thr) phosphatases is also involved in the signaling pathways leading to Tyr phosphorylation. In view of these observations and with the aim of getting a better understanding of the signaling pathways involved in human sperm capacitation, in the present work we investigated the involvement of both the cAMP/PKA and SFK/phosphatase pathways in relation to the capacitation state of the cells. For this purpose, different signaling events and sperm functional parameters were analyzed as a function of capacitation time. Results revealed a very early bicarbonate-dependent activation of PKA indicated by the rapid (1 min) increase in both phospho-PKA substrates and cAMP levels (P < 0.05). However, a complete pattern of Tyr phosphorylation was detected only after 6-h incubation at which time sperm exhibited the ability to undergo the acrosome reaction (AR) and to penetrate zona-free hamster oocytes. Sperm capacitated in the presence of the SFK inhibitor SKI606 showed a decrease in both PKA substrate and Tyr phosphorylation levels, which was overcome by exposure of sperm to the Ser/Thr phosphatase inhibitor okadaic acid (OA). However, OA was unable to induce phosphorylation when sperm were incubated under PKA-inhibitory conditions (i.e. in the absence of bicarbonate or in the presence of PKA inhibitor). Moreover, the increase in PKA activity by exposure to a cAMP analog and a phosphodiesterase inhibitor did not overcome the inhibition produced by SKI606. Whereas the presence of SKI606 during capacitation produced a negative effect (P < 0.05) on sperm motility, progesterone-induced AR and fertilizing ability, none of these inhibitions were observed when sperm were exposed to SKI606 and OA. Interestingly, different concentrations of inhibitors were required to modulate human and mouse capacitation revealing the species specificity of the molecular mechanisms underlying this process. In conclusion, our results describe for the first time the involvement of both PKA activation and Ser/Thr phosphatase down-regulation in functional human sperm capacitation and provide convincing evidence that early PKA-dependent phosphorylation is the convergent regulatory point between these two signaling pathways.
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Affiliation(s)
- M A Battistone
- Instituto de Biología y Medicina Experimental, IByME-CONICET, Ciudad Autónoma de Buenos Aires, C1428ADN Buenos Aires, Argentina
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Bauer MA, Carmona-Gutiérrez D, Ruckenstuhl C, Reisenbichler A, Megalou EV, Eisenberg T, Magnes C, Jungwirth H, Sinner FM, Pieber TR, Fröhlich KU, Kroemer G, Tavernarakis N, Madeo F. Spermidine promotes mating and fertilization efficiency in model organisms. Cell Cycle 2013; 12:346-52. [PMID: 23255134 PMCID: PMC3575463 DOI: 10.4161/cc.23199] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Spermidine is a naturally occurring polyamine involved in multiple biological processes, including DNA metabolism, autophagy and aging. Like other polyamines, spermidine is also indispensable for successful reproduction at several stages. However, a direct influence on the actual fertilization process, i.e., the fusion of an oocyte with a spermatocyte, remains uncertain. To explore this possibility, we established the mating process in the yeast Saccharomyces cerevisiae as a model for fertilization in higher eukaryotes. During human fertilization, the sperm capacitates and the acrosome reaction is necessary for penetration of the oocyte. Similarly, sexually active yeasts form a protrusion called "shmoo" as a prerequisite for mating. In this study, we demonstrate that pheromone-induced shmoo formation requires spermidine. In addition, we show that spermidine is essential for mating in yeast as well as for egg fertilization in the nematode Caenorhabditis elegans. In both cases, this occurs independently from autophagy. In synthesis, we identify spermidine as an important mating component in unicellular and multicellular model organisms, supporting an unprecedented evolutionary conservation of the mechanisms governing fertilization-related cellular fusion.
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Affiliation(s)
- Maria Anna Bauer
- Institute of Molecular Biosciences; Karl-Franzens University of Graz; Graz, Austria
| | | | | | - Angela Reisenbichler
- Institute of Molecular Biosciences; Karl-Franzens University of Graz; Graz, Austria
| | - Evgenia V. Megalou
- Institute of Molecular Biology and Biotechnology; Foundation for Research and Technology-Hellas; Heraklion, Greece
| | - Tobias Eisenberg
- Institute of Molecular Biosciences; Karl-Franzens University of Graz; Graz, Austria
| | - Christoph Magnes
- Institute of Medical Technologies and Health Management; Joanneum Research; Graz, Austria
- Department of Internal Medicine; Division of Diabetes and Metabolism; Medical University of Graz; Graz, Austria
| | - Helmut Jungwirth
- Institute of Molecular Biosciences; Karl-Franzens University of Graz; Graz, Austria
| | - Frank M. Sinner
- Institute of Medical Technologies and Health Management; Joanneum Research; Graz, Austria
- Department of Internal Medicine; Division of Diabetes and Metabolism; Medical University of Graz; Graz, Austria
| | - Thomas R. Pieber
- Institute of Medical Technologies and Health Management; Joanneum Research; Graz, Austria
- Department of Internal Medicine; Division of Diabetes and Metabolism; Medical University of Graz; Graz, Austria
| | - Kai-Uwe Fröhlich
- Institute of Molecular Biosciences; Karl-Franzens University of Graz; Graz, Austria
| | - Guido Kroemer
- INSERM; U848 and Institut Gustave Roussy; Villejuif, France
- Metabolomics Platform; Institut Gustave Roussy; Villejuif, France
- Centre de Recherche des Cordeliers; Paris, France
- Pôle de Biologie; Hôpital Européen Georges Pompidou; Assistance Publique–Hôpitaux de Paris (AP-HP); Paris, France
- Université Paris Descartes/Paris 5; Sorbonne Paris Cité; Paris, France
| | - Nektarios Tavernarakis
- Institute of Molecular Biology and Biotechnology; Foundation for Research and Technology-Hellas; Heraklion, Greece
| | - Frank Madeo
- Institute of Molecular Biosciences; Karl-Franzens University of Graz; Graz, Austria
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Abstract
Sperm intracellular pH and calcium concentration ([Ca(2+)]i) are two central factors that control sperm activity within the female reproductive tract. As such, the ion channels of the sperm plasma membrane that alter intracellular sperm [Ca(2+)] and pH play important roles in sperm physiology and the process of fertilization. Indeed, sperm ion channels regulate sperm motility, control sperm chemotaxis toward the egg in some species, and may trigger the acrosome reaction. Until recently, our understanding of these important molecules was rudimentary due to the inability to patch-clamp spermatozoa and directly record the activity of these ion channels under voltage clamp. Recently, we overcame this technical barrier and developed a method for reproducible application of the patch-clamp technique to mouse and human spermatozoa. This chapter covers important aspects of application of the patch-clamp technique to spermatozoa, such as selection of the electrophysiological equipment, isolation of spermatozoa for patch-clamp experiments, formation of the gigaohm seal with spermatozoa, and transition into the whole-cell mode of recording. We also discuss potential pitfalls in application of the patch-clamp technique to flagellar ion channels.
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Affiliation(s)
- Polina Lishko
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California, USA.
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44
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Abstract
To succeed in fertilization, spermatozoa must decode environmental cues which require a set of ion channels. Recent findings have revealed that K(+) and Cl(-) channels participate in some of the main sperm functions. This work reviews the evidence indicating the involvement of K(+) and Cl(-) channels in motility, maturation, and the acrosome reaction, and the advancement in identifying their molecular identity and modes of regulation. Improving our insight on how these channels operate will strengthen our ability to surmount some infertility problems, improve animal breeding, preserve biodiversity, and develop selective and secure male contraceptives.
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Affiliation(s)
- S J Publicover
- Department of Biosciences, University of Birmingham, Birmingham B15 2TT, UK.
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Li K, Ni Y, He Y, Chen WY, Lu JX, Cheng CY, Ge RS, Shi QX. Inhibition of sperm capacitation and fertilizing capacity by adjudin is mediated by chloride and its channels in humans. Hum Reprod 2012; 28:47-59. [PMID: 23117128 DOI: 10.1093/humrep/des384] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
STUDY QUESTION Does adjudin disrupt chloride ion (Cl⁻) ion transport function in human sperm and impede sperm capacitation and fertilizing ability in vitro? SUMMARY ANSWER In this study the results indicate that adjudin is a potent blocker of Cl⁻ channels: disrupting Cl⁻ ion transport function results in a decline in sperm capacitation and fertilizing ability in humans in vitro. WHAT IS KNOWN ALREADY Although our previous studies have demonstrated that adjudin exerts its effect by disrupting sertoli-germ cell adhesion junctions, most notably apical ectoplasmic specialization by targeting testin and actin filament bundles that disrupts the actin-based cytoskeleton in sertoli cells, it remains unclear whether adjudin impedes Cl⁻ ion transport function in the human sperm. STUDY DESIGN, SIZE AND DURATION Semen samples were obtained from 45 fertile men (aged 25-32). Spermatozoa were isolated from the semen in the human tube fluid (HTF) medium by centrifugation through a discontinuous Percoll gradient, and incubated with adjudin at 10 nM-10 µM and/or other reagents under capacitating conditions for 0-5 h. PARTICIPANTS/MATERIALS, SETTING, METHODS We evaluated the effect of adjudin and different reagents on sperm functions with which they were incubated at 37 °C. Sperm motility and hyperactivation were analyzed by a computer-assisted sperm analysis (CASA) system. Sperm capacitation and the acrosome reaction were assessed by chlortetracycline fluorescence staining. Sperm fertilizing ability was evaluated by sperm penetration of zona-free hamster egg assay, and cellular cAMP levels in spermatozoa were quantified by the EIA kit. The proteins tyrosine, serine and threonine phosphorylation in the presence or absence of adjudin were analyzed by means of a immunodetection of spermatozoa, especially, compared the effect of adjudin on sperm hyperactivation and capacitation in the complete HTF medium with the Cl⁻-deficient HTF medium as well as the various Cl⁻ channel blockers. MAIN RESULTS AND THE ROLE OF CHANCE Adjudin significantly inhibited sperm hyperactivation but not sperm motility. Adjudin-induced inhibition of sperm capacitation was reversible, and it was found to block the rhuZP₃β- and progesterone-induced acrosome reaction in a dose-dependent manner. Adjudin also blocked sperm penetration of zona-free hamster eggs, and significantly inhibited both forskolin-activated transmembrane adenylyl cyclase and soluble adenylyl cyclase activities leading to a significant decline in the cellular cAMP levels in human spermatozoa. Adjudin failed to reduce sperm protein tyrosine phosphorylation but it did prevent sperm serine and threonine protein phosphorylation. Interestingly, adjudin was found to exert its inhibitory effects on sperm capacitation and capacitation-associated events only in the complete Cl⁻-HTF medium but not Cl⁻-deficient medium, illustrating the likely involvement of Cl⁻. Adjudin inhibits the fertility capacity of human sperm is mediated by disrupting chloride ion and its transport function. LIMITATIONS, REASONS FOR CAUTION This study has examined the effect of adjudin only on human sperm capacitation and fertilizing ability in vitro and thus has some limitations. Further investigations in vivo are needed to confirm adjudin is a potent male contraceptive. WIDER IMPLICATIONS OF THE FINDINGS Our studies demonstrated that adjudin inhibition of capacitation is reversible and its toxicity is low, opening the door for the examination of adjudin as a mediator of male fertility control. Adjudin may be a safe, efficient and reversible male antifertility agent and applicable to initial clinical trials of adjudin as a male antifertility agent in humans. STUDING FUNDING/COMPETING INTEREST(S): This work was supported by the National Basic Research Program of China (2006CB504002), the Nature Science Foundation of China (Nos. 81000244 and 81170554), Zhejiang Project of Science and Technology (2011C23046), the Nature Science Fund of Zhejiang province (Nos.Y2100058 and Y2090236), the key Science and Technology Innovation Team of Zhejiang Province (No.2012R10048-07) and the National Institutes of Health (NICHD U54 HD029990 project 5), USA. The authors declare no conflict of interest.
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Affiliation(s)
- Kun Li
- Unit of Reproductive Physiology, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang 310013, China
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