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Kashir J, Mistry BV, Rajab MA, BuSaleh L, Abu-Dawud R, Ahmed HA, Alharbi S, Nomikos M, AlHassan S, Coskun S, Assiri AM. The mammalian sperm factor phospholipase C zeta is critical for early embryo division and pregnancy in humans and mice. Hum Reprod 2024; 39:1256-1274. [PMID: 38670547 PMCID: PMC11145019 DOI: 10.1093/humrep/deae078] [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: 09/28/2023] [Revised: 03/13/2024] [Indexed: 04/28/2024] Open
Abstract
STUDY QUESTION Are sperm phospholipase C zeta (PLCζ) profiles linked to the quality of embryogenesis and pregnancy? SUMMARY ANSWER Sperm PLCζ levels in both mouse and humans correlate with measures of ideal embryogenesis whereby minimal levels seem to be required to result in successful pregnancy. WHAT IS KNOWN ALREADY While causative factors underlying male infertility are multivariable, cases are increasingly associated with the efficacy of oocyte activation, which in mammals occurs in response to specific profiles of calcium (Ca2+) oscillations driven by sperm-specific PLCζ. Although sperm PLCζ abrogation is extensively linked with human male infertility where oocyte activation is deficient, less is clear as to whether sperm PLCζ levels or localization underlies cases of defective embryogenesis and failed pregnancy following fertility treatment. STUDY DESIGN, SIZE, DURATION A cohort of 54 couples undergoing fertility treatment were recruited at the assisted reproductive technology laboratory at the King Faisal Hospital and Research Centre, Riyadh, Kingdom of Saudi Arabia. The recruitment criteria for males was a minimum sperm concentration of 5×106 sperm/ml, while all female patients had to have at least five oocytes. Sperm PLCζ analysis was performed in research laboratories, while semen assessments were performed, and time-lapse morphokinetic data were obtained, in the fertility clinic as part of routine treatment. The CRISPR/Cas9 system was concurrently used to induce indels and single-nucleotide mutations within the Plcζ gene to generate strains of Plcζ mutant mice. Sperm PLCζ was evaluated using immunofluorescence and immunoblotting with an antibody of confirmed consistent specificity against PLCζ. PARTICIPANTS/MATERIALS, SETTING, METHODS We evaluated PLCζ profiles in sperm samples from 54 human couples undergoing fertility treatment in the context of time-lapse morphokinetic analysis of resultant embryos, correlating such profiles to pregnancy status. Concurrently, we generated two strains of mutant Plcζ mice using CRISPR/Cas9, and performed IVF with wild type (WT) oocytes and using WT or mutant Plcζ sperm to generate embryos. We also assessed PLCζ status in WT and mutant mice sperm in the context of time-lapse morphokinetic analysis and breeding outcomes. MAIN RESULTS AND THE ROLE OF CHANCE A significant (P ≤ 0.05) positive relationship was observed between both PLCζ relative fluorescence and relative density with the times taken for both the second cell division (CC2) (r = 0.26 and r = 0.43, respectively) and the third cell division (S2) (r = 0.26). Examination of localization patterns also indicated significant correlations between the presence or absence of sperm PLCζ and CC2 (r = 0.27 and r = -0.27, respectively; P ≤ 0.025). Human sperm PLCζ levels were at their highest in the ideal times of CC2 (8-12 h) compared to time ranges outside the ideal timeframe (<8 and >12 h) where levels of human sperm PLCζ were lower. Following assignment of PLCζ level thresholds, quantification revealed a significantly higher (P ≤ 0.05) rate of successful pregnancy in values larger than the assigned cut-off for both relative fluorescence (19% vs 40%, respectively) and relative density (8% vs 54%, respectively). Immunoblotting indicated a single band for PLCζ at 74 kDa in sperm from WT mice, while a single band was also observed in sperm from heterozygous of Plcζ mutant mouse sperm, but at a diminished intensity. Immunofluorescent analysis indicated the previously reported (Kashir et al., 2021) fluorescence patterns in WT sperm, while sperm from Plcζ mutant mice exhibited a significantly diminished and dispersed pattern at the acrosomal region of the sperm head. Breeding experiments indicated a significantly reduced litter size of mutant Plcζ male mice compared to WT mice, while IVF-generated embryos using sperm from mutant Plcζ mice exhibited high rates of polyspermy, and resulted in significantly reduced numbers of these embryos reaching developmental milestones. LIMITATIONS, REASONS FOR CAUTION The human population examined was relatively small, and should be expanded to examine a larger multi-centre cohort. Infertility conditions are often multivariable, and it was not possible to evaluate all these in human patients. However, our mutant Plcζ mouse experiments do suggest that PLCζ plays a significant role in early embryo development. WIDER IMPLICATIONS OF THE FINDINGS We found that minimal levels of PLCζ within a specific range were required for optimal early embryogenesis, correlating with increased pregnancy. Levels of sperm PLCζ below specific thresholds were associated with ineffective embryogenesis and lower pregnancy rates, despite eliciting successful fertilization in both mice and humans. To our knowledge, this represents the first time that PLCζ levels in sperm have been correlated to prognostic measures of embryogenic efficacy and pregnancy rates in humans. Our data suggest for the first time that the clinical utilization of PLCζ may stand to benefit not just a specific population of male infertility where oocyte activation is completely deficient (wherein PLCζ is completely defective/abrogated), but also perhaps the larger population of couples seeking fertility treatment. STUDY FUNDING/COMPETING INTEREST(S) J.K. is supported by a faculty start up grant awarded by Khalifa University (FSU-2023-015). This study was also supported by a Healthcare Research Fellowship Award (HF-14-16) from Health and Care Research Wales (HCRW) to J.K., alongside a National Science, Technology, and Innovation plan (NSTIP) project grant (15-MED4186-20) awarded by the King Abdulaziz City for Science and Technology (KACST) for J.K. and A.M.A. The authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER N/A.
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Affiliation(s)
- Junaid Kashir
- Department of Biological Sciences, College of Medicine and Health Sciences, Khalifa University, Abu Dhabi, United Arab Emirates
- Center for Biotechnology, Khalifa University, Abu Dhabi, United Arab Emirates
- Department of Comparative Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Bhavesh V Mistry
- Department of Comparative Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Mohamed A Rajab
- Department of Comparative Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Lujain BuSaleh
- Department of Comparative Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
- College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Raed Abu-Dawud
- Department of Comparative Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
- Institute for Molecular Medicine, MSH Medical School, Hamburg, Germany
| | - Hala A Ahmed
- Department of Comparative Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Sarah Alharbi
- Department of Pathology and Laboratory Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Michail Nomikos
- College of Medicine, QU Health, Qatar University, Doha, Qatar
| | - Saad AlHassan
- Department of Obstetrics and Gynaecology, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Serdar Coskun
- College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
- Department of Pathology and Laboratory Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Abdullah M Assiri
- Department of Comparative Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
- College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
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Lykins J, Moschitto MJ, Zhou Y, Filippova EV, Le HV, Tomita T, Fox BA, Bzik DJ, Su C, Rajagopala SV, Flores K, Spano F, Woods S, Roberts CW, Hua C, El Bissati K, Wheeler KM, Dovgin S, Muench SP, McPhillie M, Fishwick CW, Anderson WF, Lee PJ, Hickman M, Weiss LM, Dubey JP, Lorenzi HA, Silverman RB, McLeod RL. From TgO/GABA-AT, GABA, and T-263 Mutant to Conception of Toxoplasma. iScience 2024; 27:108477. [PMID: 38205261 PMCID: PMC10776954 DOI: 10.1016/j.isci.2023.108477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 04/28/2023] [Accepted: 11/13/2023] [Indexed: 01/12/2024] Open
Abstract
Toxoplasma gondii causes morbidity, mortality, and disseminates widely via cat sexual stages. Here, we find T. gondii ornithine aminotransferase (OAT) is conserved across phyla. We solve TgO/GABA-AT structures with bound inactivators at 1.55 Å and identify an inactivator selective for TgO/GABA-AT over human OAT and GABA-AT. However, abrogating TgO/GABA-AT genetically does not diminish replication, virulence, cyst-formation, or eliminate cat's oocyst shedding. Increased sporozoite/merozoite TgO/GABA-AT expression led to our study of a mutagenized clone with oocyst formation blocked, arresting after forming male and female gametes, with "Rosetta stone"-like mutations in genes expressed in merozoites. Mutations are similar to those in organisms from plants to mammals, causing defects in conception and zygote formation, affecting merozoite capacitation, pH/ionicity/sodium-GABA concentrations, drawing attention to cyclic AMP/PKA, and genes enhancing energy or substrate formation in TgO/GABA-AT-related-pathways. These candidates potentially influence merozoite's capacity to make gametes that fuse to become zygotes, thereby contaminating environments and causing disease.
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Affiliation(s)
- Joseph Lykins
- Pritzker School of Medicine, University of Chicago, Chicago, IL 60637, USA
| | - Matthew J. Moschitto
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, and Center for Developmental Therapeutics, Northwestern University, Evanston, IL 60208-3113, USA
| | - Ying Zhou
- Department of Ophthalmology and Visual Sciences, The University of Chicago, Chicago, IL 60637, USA
| | - Ekaterina V. Filippova
- Center for Structural Genomics of Infectious Diseases and the Department of Biochemistry and Molecular Genetics, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Hoang V. Le
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, and Center for Developmental Therapeutics, Northwestern University, Evanston, IL 60208-3113, USA
| | - Tadakimi Tomita
- Division of Parasitology, Department of Pathology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Barbara A. Fox
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - David J. Bzik
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - Chunlei Su
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, USA
| | - Seesandra V. Rajagopala
- Department of Infectious Diseases, The J. Craig Venter Institute, 9704 Medical Center Drive, Rockville, MD 20850, USA
| | - Kristin Flores
- Center for Structural Genomics of Infectious Diseases and the Department of Biochemistry and Molecular Genetics, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Furio Spano
- Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Stuart Woods
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow Scotland, UK
| | - Craig W. Roberts
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow Scotland, UK
| | - Cong Hua
- Department of Ophthalmology and Visual Sciences, The University of Chicago, Chicago, IL 60637, USA
| | - Kamal El Bissati
- Department of Ophthalmology and Visual Sciences, The University of Chicago, Chicago, IL 60637, USA
| | - Kelsey M. Wheeler
- Department of Ophthalmology and Visual Sciences, The University of Chicago, Chicago, IL 60637, USA
| | - Sarah Dovgin
- Department of Ophthalmology and Visual Sciences, The University of Chicago, Chicago, IL 60637, USA
| | - Stephen P. Muench
- School of Biomedical Sciences and Astbury Centre for Structural Molecular Biology, The University of Leeds, Leeds, West York LS2 9JT, UK
| | - Martin McPhillie
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Colin W.G. Fishwick
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Wayne F. Anderson
- Center for Structural Genomics of Infectious Diseases and the Department of Biochemistry and Molecular Genetics, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, USA
- Department of Pharmacology, Northwestern University, Chicago, IL 60611, USA
| | - Patricia J. Lee
- Division of Experimental Therapeutics, Military Malaria Research Program, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Mark Hickman
- Division of Experimental Therapeutics, Military Malaria Research Program, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Louis M. Weiss
- Division of Parasitology, Department of Pathology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Jitender P. Dubey
- Animal Parasitic Diseases Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, Beltsville, MD 20705, USA
| | - Hernan A. Lorenzi
- Department of Infectious Diseases, The J. Craig Venter Institute, 9704 Medical Center Drive, Rockville, MD 20850, USA
| | - Richard B. Silverman
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, and Center for Developmental Therapeutics, Northwestern University, Evanston, IL 60208-3113, USA
- Department of Pharmacology, Northwestern University, Chicago, IL 60611, USA
| | - Rima L. McLeod
- Department of Ophthalmology and Visual Sciences, The University of Chicago, Chicago, IL 60637, USA
- Department of Pediatrics (Infectious Diseases), Institute of Genomics, Genetics, and Systems Biology, Global Health Center, Toxoplasmosis Center, CHeSS, The College, University of Chicago, Chicago, IL 60637, USA
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Swann K. Sperm-Induced Ca 2+ Release in Mammalian Eggs: The Roles of PLCζ, InsP 3, and ATP. Cells 2023; 12:2809. [PMID: 38132129 PMCID: PMC10741559 DOI: 10.3390/cells12242809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 11/29/2023] [Accepted: 12/06/2023] [Indexed: 12/23/2023] Open
Abstract
Mammalian egg activation at fertilization is triggered by a long-lasting series of increases in cytosolic Ca2+ concentration. These Ca2+ oscillations are due to the production of InsP3 within the egg and the subsequent release of Ca2+ from the endoplasmic reticulum into the cytosol. The generation of InsP3 is initiated by the diffusion of sperm-specific phospholipase Czeta1 (PLCζ) into the egg after gamete fusion. PLCζ enables a positive feedback loop of InsP3 production and Ca2+ release which then stimulates further InsP3 production. Most cytosolic Ca2+ increases in eggs at fertilization involve a fast Ca2+ wave; however, due to the limited diffusion of InsP3, this means that InsP3 must be generated from an intracellular source rather than at the plasma membrane. All mammalian eggs studied generated Ca2+ oscillations in response to PLCζ, but the sensitivity of eggs to PLCζ and to some other stimuli varies between species. This is illustrated by the finding that incubation in Sr2+ medium stimulates Ca2+ oscillations in mouse and rat eggs but not eggs from other mammalian species. This difference appears to be due to the sensitivity of the type 1 InsP3 receptor (IP3R1). I suggest that ATP production from mitochondria modulates the sensitivity of the IP3R1 in a manner that could account for the differential sensitivity of eggs to stimuli that generate Ca2+ oscillations.
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Affiliation(s)
- Karl Swann
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
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Duma-Pauta JM, Juárez-López NO, Gutiérrez-Pérez O, Córdova-Izquierdo A, Vigueras-Villaseñor RM, Juárez-Mosqueda MDL. Cryopreservation, in addition to protein tyrosine phosphorylation, alters the distribution of phosphatidyl inositol bisphosphate and the localization of cytoskeletal and signaling proteins (gelsolin, tyrosine kinase c-SRC and phospholipase C-ζ) in the perinuclear theca of boar sperm. Cryobiology 2023; 113:104589. [PMID: 37778407 DOI: 10.1016/j.cryobiol.2023.104589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 09/26/2023] [Accepted: 09/27/2023] [Indexed: 10/03/2023]
Abstract
Cryopreservation of boar spermatozoa affects the perinuclear theca (PT) and involves several proteins and molecules that play important roles during capacitation and the acrosomal reaction. The objective of the present study was to evaluate whether the deleterious effects of cryopreservation in addition to protein tyrosine phosphorylation are accompanied by changes in the distribution of phosphatidyl inositol bisphosphate (PIP2) and the localization of cytoskeletal and signaling proteins in the perinuclear theca of cryopreserved boar spermatozoa. For this purpose, by immunocytochemistry (IC) the changes in localization of phosphorylated proteins in tyrosine residues, gelsolin, c-SRC kinase and PLC-ζ, as well as in the distribution of phosphatidyl inositol bisphosphate were analyzed in thawed spermatozoa (T) non capacitated (NC), capacitated (C) and in those with acrosomal reaction (AR) and compared with fresh spermatozoa (F) under the same physiological status. Western blotting (WB) and co-immunoprecipitation were performed to confirm the presence of these proteins in PT and to determine the interaction between these molecules. IC showed that immunostaining for phosphorylated proteins significantly increased in the acrosomal region and flagellum in TNC spermatozoa (p < 0.05). The proportion of cells displaying immunolabeling for gelsolin in the acrosomal region decreased after capacitation in cryopreserved spermatozoa; the same change was found (p < 0.05) in the proportion of spermatozoa immunoreactive to PIP2 in the sperm head. c-SRC was observed in the equatorial segment and acrosomal region, subdomains that coincide with the site where phosphorylated proteins were detected. PLC-ζ immunolocalization in fresh spermatozoa underwent changes after capacitation and acrosomal reaction, with a significant increase in the equatorial segment and post-acrosomal region in cryopreserved spermatozoa (p < 0.05). WB analysis indicated the presence of gelsolin, c-SRC and PLC-ζ in PT; besides, we confirmed that gelsolin co-immunoprecipitated with c-SRC and PLC-ζ, which changes according to the physiological state of spermatozoa. As a conclusion, cryopreservation together with increased immunodetection of tyrosine phosphorylated proteins decreases the detection of PIP2 and alters the immunolocalization patterns of gelsolin, c-SRC and PLC-ζ in the PT in boar spermatozoa.
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Affiliation(s)
- José Mauricio Duma-Pauta
- Universidad Nacional Autónoma de México, Departamento de Morfología, Facultad de Medicina Veterinaria y Zootecnia, Ciudad Universitaria No. 3000, Ciudad de México, CP, 04510, Mexico; Universidad de Cuenca, Laboratorio de Biotecnología de la Reproducción Animal, Facultad de Ciencias Agropecuarias, Avda. 12 de octubre, EC101205, Cuenca, Ecuador.
| | - Noé Orlando Juárez-López
- Universidad Nacional Autónoma de México, Departamento de Genética y Bioestadística, Facultad de Medicina Veterinaria y Zootecnia, Ciudad Universitaria No. 3000, Ciudad deMéxico, CP, 04510, Mexico.
| | - Oscar Gutiérrez-Pérez
- Universidad Nacional Autónoma de México, Centro de Enseñanaza de Investigación y Extensión en Producción Porcina, Facultad de Medicina Veterinaria y Zootecnia, Ciudad Universitaria No. 3000, Ciudad de México, CP. 04510, México.
| | - Alejandro Córdova-Izquierdo
- Universidad Autónoma Metropolitana Unidad Xochimilco, Departamento de Agricultura y Producción Animal, Calzada del hueso 1100, Ciudad de México, CP, 04960, Mexico.
| | - Rosa María Vigueras-Villaseñor
- Instituto Nacional de Pediatría, Subdirección de Medicina Experimental, Av. Insurgentes Sur 3700-C, Ciudad de México, CP, 04530, Mexico
| | - María de Lourdes Juárez-Mosqueda
- Universidad Nacional Autónoma de México, Departamento de Morfología, Facultad de Medicina Veterinaria y Zootecnia, Ciudad Universitaria No. 3000, Ciudad de México, CP, 04510, Mexico.
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Bafleh WS, Abdulsamad HMR, Al-Qaraghuli SM, El Khatib RY, Elbahrawi RT, Abdukadir AM, Alsawae SM, Dimassi Z, Hamdan H, Kashir J. Applications of advances in mRNA-based platforms as therapeutics and diagnostics in reproductive technologies. Front Cell Dev Biol 2023; 11:1198848. [PMID: 37305677 PMCID: PMC10250609 DOI: 10.3389/fcell.2023.1198848] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 05/18/2023] [Indexed: 06/13/2023] Open
Abstract
The recent COVID-19 pandemic led to many drastic changes in not only society, law, economics, but also in science and medicine, marking for the first time when drug regulatory authorities cleared for use mRNA-based vaccines in the fight against this outbreak. However, while indeed representing a novel application of such technology in the context of vaccination medicine, introducing RNA into cells to produce resultant molecules (proteins, antibodies, etc.) is not a novel principle. It has been common practice to introduce/inject mRNA into oocytes and embryos to inhibit, induce, and identify several factors in a research context, while such aspects have also been proposed as potential therapeutic and diagnostic applications to combat infertility in humans. Herein, we describe key areas where mRNA-based platforms have thus far represented potential areas of clinical applications, describing the advantages and limitations of such applications. Finally, we also discuss how recent advances in mRNA-based platforms, driven by the recent pandemic, may stand to benefit the treatment of infertility in humans. We also present brief future directions as to how we could utilise recent and current advancements to enhance RNA therapeutics within reproductive biology, specifically with relation to oocyte and embryo delivery.
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Affiliation(s)
- Wjdan S. Bafleh
- Department of Physiology and Immunology, College of Medicine and Health Sciences, Khalifa University, Abu Dhabi, United Arab Emirates
| | - Haia M. R. Abdulsamad
- Department of Physiology and Immunology, College of Medicine and Health Sciences, Khalifa University, Abu Dhabi, United Arab Emirates
| | - Sally M. Al-Qaraghuli
- Department of Physiology and Immunology, College of Medicine and Health Sciences, Khalifa University, Abu Dhabi, United Arab Emirates
| | - Riwa Y. El Khatib
- Department of Physiology and Immunology, College of Medicine and Health Sciences, Khalifa University, Abu Dhabi, United Arab Emirates
| | - Rawdah Taha Elbahrawi
- Department of Physiology and Immunology, College of Medicine and Health Sciences, Khalifa University, Abu Dhabi, United Arab Emirates
| | - Azhar Mohamud Abdukadir
- Department of Physiology and Immunology, College of Medicine and Health Sciences, Khalifa University, Abu Dhabi, United Arab Emirates
| | | | - Zakia Dimassi
- Department of Pediatrics, College of Medicine and Health Sciences, Khalifa University, Abu Dhabi, United Arab Emirates
| | - Hamdan Hamdan
- Department of Physiology and Immunology, College of Medicine and Health Sciences, Khalifa University, Abu Dhabi, United Arab Emirates
- Healthcare Engineering Innovation Center (HEIC), Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
| | - Junaid Kashir
- Department of Biology, College of Arts and Science, Khalifa University, Abu Dhabi, United Arab Emirates
- Department of Comparative Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
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Bovine ICSI: limiting factors, strategies to improve its efficiency and alternative approaches. ZYGOTE 2022; 30:749-767. [PMID: 36082429 DOI: 10.1017/s0967199422000296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Intracytoplasmic sperm injection (ICSI) is an assisted reproductive technique mainly used to overcome severe infertility problems associated with the male factor, but in cattle its efficiency is far from optimal. Artificial activation treatments combining ionomycin (Io) with 6-dimethylaminopurine after piezo-ICSI or anisomycin after conventional ICSI have recently increased the blastocyst rate obtained. Compounds to capacitate bovine spermatozoa, such as heparin and methyl-β-cyclodextrin and compounds to destabilize sperm membranes such as NaOH, lysolecithin and Triton X-100, have been assessed, although they have failed to substantially improve post-ICSI embryonic development. Disulfide bond reducing agents, such as dithiothreitol (DTT), dithiobutylamine and reduced glutathione, have been assessed to decondense the hypercondensed head of bovine spermatozoa, the two latter being more efficient than DTT and less harmful. Although piezo-directed ICSI without external activation has generated high fertilization rates and modest rates of early embryo development, other studies have required exogenous activation to improve the results. This manuscript thoroughly reviews the different strategies used in bovine ICSI to improve its efficiency and proposes some alternative approaches, such as the use of extracellular vesicles (EVs) as 'biological methods of oocyte activation' or the incorporation of EVs in the in vitro maturation and/or culture medium as antioxidant defence agents to improve the competence of the ooplasm, as well as a preincubation of the spermatozoa in estrous oviductal fluid to induce physiological capacitation and acrosome reaction before ICSI, and the use of hyaluronate in the sperm immobilization medium.
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Kashir J, Ganesh D, Jones C, Coward K. OUP accepted manuscript. Hum Reprod Open 2022; 2022:hoac003. [PMID: 35261925 PMCID: PMC8894871 DOI: 10.1093/hropen/hoac003] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 01/16/2022] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Oocyte activation deficiency (OAD) is attributed to the majority of cases underlying failure of ICSI cycles, the standard treatment for male factor infertility. Oocyte activation encompasses a series of concerted events, triggered by sperm-specific phospholipase C zeta (PLCζ), which elicits increases in free cytoplasmic calcium (Ca2+) in spatially and temporally specific oscillations. Defects in this specific pattern of Ca2+ release are directly attributable to most cases of OAD. Ca2+ release can be clinically mediated via assisted oocyte activation (AOA), a combination of mechanical, electrical and/or chemical stimuli which artificially promote an increase in the levels of intra-cytoplasmic Ca2+. However, concerns regarding safety and efficacy underlie potential risks that must be addressed before such methods can be safely widely used. OBJECTIVE AND RATIONALE Recent advances in current AOA techniques warrant a review of the safety and efficacy of these practices, to determine the extent to which AOA may be implemented in the clinic. Importantly, the primary challenges to obtaining data on the safety and efficacy of AOA must be determined. Such questions require urgent attention before widespread clinical utilization of such protocols can be advocated. SEARCH METHODS A literature review was performed using databases including PubMed, Web of Science, Medline, etc. using AOA, OAD, calcium ionophores, ICSI, PLCζ, oocyte activation, failed fertilization and fertilization failure as keywords. Relevant articles published until June 2019 were analysed and included in the review, with an emphasis on studies assessing large-scale efficacy and safety. OUTCOMES Contradictory studies on the safety and efficacy of AOA do not yet allow for the establishment of AOA as standard practice in the clinic. Heterogeneity in study methodology, inconsistent sample inclusion criteria, non-standardized outcome assessments, restricted sample size and animal model limitations render AOA strictly experimental. The main scientific concern impeding AOA utilization in the clinic is the non-physiological method of Ca2+ release mediated by most AOA agents, coupled with a lack of holistic understanding regarding the physiological mechanism(s) underlying Ca2+ release at oocyte activation. LIMITATIONS, REASONS FOR CAUTION The number of studies with clinical relevance using AOA remains significantly low. A much wider range of studies examining outcomes using multiple AOA agents are required. WIDER IMPLICATIONS In addition to addressing the five main challenges of studies assessing AOA safety and efficacy, more standardized, large-scale, multi-centre studies of AOA, as well as long-term follow-up studies of children born from AOA, would provide evidence for establishing AOA as a treatment for infertility. The delivery of an activating agent that can more accurately recapitulate physiological fertilization, such as recombinant PLCζ, is a promising prospect for the future of AOA. Further to PLCζ, many other avenues of physiological oocyte activation also require urgent investigation to assess other potential physiological avenues of AOA. STUDY FUNDING/COMPETING INTERESTS D.G. was supported by Stanford University’s Bing Overseas Study Program. J.K. was supported by a Healthcare Research Fellowship Award (HF-14-16) made by Health and Care Research Wales (HCRW), alongside a National Science, Technology, and Innovation plan (NSTIP) project grant (15-MED4186-20) awarded by the King Abdulaziz City for Science and Technology (KACST). The authors have no competing interests to declare.
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Affiliation(s)
| | | | - Celine Jones
- Nuffield Department of Women’s & Reproductive Health, University of Oxford, Level 3, Women’s Centre, John Radcliffe Hospital, Oxford, UK
| | - Kevin Coward
- Correspondence address. Nuffield Department of Women’s & Reproductive Health, University of Oxford, Level 3, Women’s Centre, John Radcliffe Hospital, Oxford, OS3 9DU, UK. E-mail: https://orcid.org/0000-0003-3577-4041
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8
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Chen C, Sun T, Yin M, Yan Z, Yu W, Long H, Wang L, Liao X, Yan Z, Li W, Lyu Q. Ionomycin-induced mouse oocyte activation can disrupt preimplantation embryo development through increased reactive oxygen species reaction and DNA damage. Mol Hum Reprod 2021; 26:773-783. [PMID: 32697831 DOI: 10.1093/molehr/gaaa056] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 07/01/2020] [Indexed: 12/19/2022] Open
Abstract
Oocyte activation induced by calcium oscillations is an important process in normal fertilization and subsequent embryogenesis. In the clinical-assisted reproduction, artificial oocyte activation (AOA) is an effective method to improve the clinical outcome of patients with null or low fertilization rate after ICSI. However, little is known about the effect of AOA on preimplantation embryo development in cases with normal fertilization by ICSI. Here, we used ionomycin at different concentrations to activate oocytes after ICSI with normal sperm and evaluated energy metabolism and preimplantation embryo development. We found that a high concentration of ionomycin increased the frequency and amplitude of calcium oscillation patterns, affecting the balance of mitochondrial energy metabolism, leading to increased reactive oxygen species (ROS) and decreased ATP. Eventually, it increases DNA damage and decreases blastocyst formation. In addition, the addition of vitamin C to the culture medium ameliorated the increase in ROS and DNA damage and rescued the abnormal embryo development caused by excessive ionomycin activation. This study provides a perspective that the improper application of AOA may have adverse effects on preimplantation embryo development. Thus, clinical AOA treatment should be cautiously administered.
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Affiliation(s)
- Chen Chen
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Tingye Sun
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China.,Department of Gynaecology, Guangdong Second Provincial General Hospital, Guangzhou, People's Republic of China
| | - Mingru Yin
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Zhiguang Yan
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Weina Yu
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Hui Long
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Li Wang
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Xiaoyu Liao
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Zheng Yan
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Wenzhi Li
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Qifeng Lyu
- Department of Assisted Reproduction, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
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9
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Diagnosis and Treatment of Male Infertility-Related Fertilization Failure. J Clin Med 2020; 9:jcm9123899. [PMID: 33271815 PMCID: PMC7761017 DOI: 10.3390/jcm9123899] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 11/26/2020] [Accepted: 11/27/2020] [Indexed: 12/22/2022] Open
Abstract
Infertility affects approximately 15% of reproductive-aged couples worldwide, of which up to 30% of the cases are caused by male factors alone. The origin of male infertility is mostly attributed to sperm abnormalities, of which many are caused by genetic defects. The development of intracytoplasmic sperm injection (ICSI) has helped to circumvent most male infertility conditions. However, there is still a challenging group of infertile males whose sperm, although having normal sperm parameters, are unable to activate the oocyte, even after ICSI treatment. While ICSI generally allows fertilization rates of 70 to 80%, total fertilization failure (FF) still occurs in 1 to 3% of ICSI cycles. Phospholipase C zeta (PLCζ) has been demonstrated to be a critical sperm oocyte activating factor (SOAF) and the absence, reduced, or altered forms of PLCζ have been shown to cause male infertility-related FF. The purpose of this review is to (i) summarize the current knowledge on PLCζ as the critical sperm factor for successful fertilization, as well as to discuss the existence of alternative sperm-induced oocyte activation mechanisms, (ii) describe the diagnostic tests available to determine the cause of FF, and (iii) summarize the beneficial effect of assisted oocyte activation (AOA) to overcome FF.
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10
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Gonzalez-Castro RA, Amoroso-Sanches F, Stokes JE, Graham JK, Carnevale EM. Localisation of phospholipase Cζ1 (PLCZ1) and postacrosomal WW-binding protein (WBP2 N-terminal like) on equine spermatozoa and flow cytometry quantification of PLCZ1 and association with cleavage in vitro. Reprod Fertil Dev 2020; 31:1778-1792. [PMID: 31597592 DOI: 10.1071/rd19217] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 09/03/2019] [Indexed: 02/01/2023] Open
Abstract
Oocyte activation is initiated when a fertilising spermatozoon delivers sperm-borne oocyte-activating factor(s) into the oocyte cytoplasm. Candidates for oocyte activation include two proteins, phospholipase Cζ1 (PLCZ1) and postacrosomal WW-binding protein (PAWP; also known as WBP2 N-terminal like (WBP2NL)). We localised PLCZ1 and WBP2NL/PAWP in stallion spermatozoa and investigated the PLCZ1 content and sperm parameters as well as cleavage after intracytoplasmic sperm injection (ICSI). PLCZ1 was identified as 71-kDa protein in the acrosomal and postacrosomal regions, midpiece and principal piece of the tail. Anti-WBP2NL antibody identified two WBP2NL bands (~28 and ~32kDa) in the postacrosomal region, midpiece and principal piece of the tail. PLCZ1 and WBP2NL expression was positively correlated (P=0.04) in sperm heads. Flow cytometry evaluation of PLCZ1 revealed large variations in fluorescence intensity and the percentage of positively labelled spermatozoa among stallions. PLCZ1 expression was significantly higher in viable than non-viable spermatozoa, and DNA fragmentation was negatively correlated with PLCZ1 expression and the percentage of positively labelled spermatozoa (P<0.05). The use of equine sperm populations considered to have high versus low PLCZ1 content resulted in significantly higher cleavage rates after ICSI of bovine and equine oocytes, supporting the importance of PLCZ1 for oocyte activation.
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Affiliation(s)
- Raul A Gonzalez-Castro
- Equine Reproduction Laboratory, Department of Biomedical Sciences, Colorado State University, 3101 Rampart Rd, Fort Collins, Colorado, 80521, USA
| | - Fabio Amoroso-Sanches
- Equine Reproduction Laboratory, Department of Biomedical Sciences, Colorado State University, 3101 Rampart Rd, Fort Collins, Colorado, 80521, USA
| | - JoAnne E Stokes
- Equine Reproduction Laboratory, Department of Biomedical Sciences, Colorado State University, 3101 Rampart Rd, Fort Collins, Colorado, 80521, USA
| | - James K Graham
- Equine Reproduction Laboratory, Department of Biomedical Sciences, Colorado State University, 3101 Rampart Rd, Fort Collins, Colorado, 80521, USA
| | - Elaine M Carnevale
- Equine Reproduction Laboratory, Department of Biomedical Sciences, Colorado State University, 3101 Rampart Rd, Fort Collins, Colorado, 80521, USA; and Corresponding author.
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11
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Nakai M, Ito J, Suyama A, Kageyama A, Tobari Y, Kashiwazaki N. Phospholipase Cζ (PLCζ) versus postacrosomal sheath WW domain-binding protein (PAWP): Which molecule will survive as a sperm factor? Anim Sci J 2020; 91:e13345. [PMID: 32219949 PMCID: PMC7140179 DOI: 10.1111/asj.13345] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Revised: 12/26/2019] [Accepted: 12/27/2019] [Indexed: 11/27/2022]
Abstract
During mammalian fertilization, sperm is fused with the oocyte's membrane, triggering the resumption of meiosis from the metaphase II arrest, the extrusion of the second polar body, and the exocytosis of cortical granules; these events are collectively called 'oocyte activation.' In all species studied to date, the transient rise in the cytosolic level of calcium (in particular, the repeated calcium increases called 'calcium oscillations' in mammals) is required for these events. Researchers have focused on identifying the factor(s) that can induce calcium oscillations during fertilization. Sperm‐specific phospholipase C, i.e., PLC zeta (PLCζ), is a strong candidate of the factor(s), and several research groups using different species obtained evidence that PLCζ is a sperm factor that can induce calcium oscillations during fertilization. However, postacrosomal sheath Tryptophan‐Tryptophan (WW)—domain‐binding protein (PAWP) was recently shown to have a pivotal role in inducing calcium oscillations in some species. In this review, we focus on PLCζ and PAWP as sperm factors, and we discuss this controversy: Which of these two molecules survives as a sperm factor?
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Affiliation(s)
- Michiko Nakai
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Japan
| | - Junya Ito
- Laboratory of Animal Reproduction, School of Veterinary Medicine, Azabu University, Sagamihara, Japan.,Graduate School of Veterinary Sciences, Azabu University, Sagamihara, Japan
| | - Ayumi Suyama
- Graduate School of Veterinary Sciences, Azabu University, Sagamihara, Japan
| | - Atsuko Kageyama
- Graduate School of Veterinary Sciences, Azabu University, Sagamihara, Japan
| | - Yasuko Tobari
- Laboratory of Animal Genetics and Breeding, School of Veterinary Medicine, Azabu University, Sagamihara, Japan
| | - Naomi Kashiwazaki
- Laboratory of Animal Reproduction, School of Veterinary Medicine, Azabu University, Sagamihara, Japan.,Graduate School of Veterinary Sciences, Azabu University, Sagamihara, Japan
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12
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Kashir J. Increasing associations between defects in phospholipase C zeta and conditions of male infertility: not just ICSI failure? J Assist Reprod Genet 2020; 37:1273-1293. [PMID: 32285298 PMCID: PMC7311621 DOI: 10.1007/s10815-020-01748-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 03/12/2020] [Indexed: 12/12/2022] Open
Abstract
PURPOSE Oocyte activation is a fundamental event at mammalian fertilization. In mammals, this process is initiated by a series of characteristic calcium (Ca2+) oscillations, induced by a sperm-specific phospholipase C (PLC) termed PLCzeta (PLCζ). Dysfunction/reduction/deletion of PLCζ is associated with forms of male infertility where the sperm is unable to initiate Ca2+ oscillations and oocyte activation, specifically in cases of fertilization failure. This review article aims to systematically summarize recent advancements and controversies in the field to update expanding clinical associations between PLCζ and various male factor conditions. This article also discusses how such associations may potentially underlie defective embryogenesis and recurrent implantation failure following fertility treatments, alongside potential diagnostic and therapeutic PLCζ approaches, aiming to direct future research efforts to utilize such knowledge clinically. METHODS An extensive literature search was performed using literature databases (PubMed/MEDLINE/Web of Knowledge) focusing on phospholipase C zeta (PLCzeta; PLCζ), oocyte activation, and calcium oscillations, as well as specific male factor conditions. RESULTS AND DISCUSSION Defective PLCζ or PLCζ-induced Ca2+ release can be linked to multiple forms of male infertility including abnormal sperm parameters and morphology, sperm DNA fragmentation and oxidation, and abnormal embryogenesis/pregnancies. Such sperm exhibit absent/reduced levels, and abnormal localization patterns of PLCζ within the sperm head. CONCLUSIONS Defective PLCζ and abnormal patterns of Ca2+ release are increasingly suspected a significant causative factor underlying abnormalities or insufficiencies in Ca2+ oscillation-driven early embryogenic events. Such cases could potentially strongly benefit from relevant therapeutic and diagnostic applications of PLCζ, or even alternative mechanisms, following further focused research efforts.
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Affiliation(s)
- Junaid Kashir
- College of Medicine, Alfaisal University, Riyadh, Kingdom of Saudi Arabia. .,School of Biosciences, Cardiff University, Cardiff, UK. .,Department of Comparative Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Kingdom of Saudi Arabia.
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13
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Saleh A, Kashir J, Thanassoulas A, Safieh-Garabedian B, Lai FA, Nomikos M. Essential Role of Sperm-Specific PLC-Zeta in Egg Activation and Male Factor Infertility: An Update. Front Cell Dev Biol 2020; 8:28. [PMID: 32064262 PMCID: PMC7000359 DOI: 10.3389/fcell.2020.00028] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 01/14/2020] [Indexed: 12/16/2022] Open
Abstract
Sperm-specific phospholipase C zeta (PLCζ) is widely considered to be the physiological stimulus responsible for generating calcium (Ca2+) oscillations that induce egg activation and early embryonic development during mammalian fertilization. In the mammalian testis, PLCζ expression is detected at spermiogenesis following elongated spermatid differentiation. Sperm-delivered PLCζ induces Ca2+ release via the inositol 1,4,5-trisphosphate (InsP3) signaling pathway. PLCζ is the smallest known mammalian PLC isoform identified to date, with the simplest domain organization. However, the distinctive biochemical properties of PLCζ compared with other PLC isoforms contribute to its unique potency in stimulating cytosolic Ca2+ oscillations within mammalian eggs. Moreover, studies describing PLCζ “knockout” mouse phenotypes confirm the supreme importance of PLCζ at egg activation and monospermic fertilization in mice. Importantly, a number of clinical reports have highlighted the crucial importance of PLCζ in human fertilization by associating PLCζ deficiencies with certain forms of male factor infertility. Herein, we give an update on recent advances that have refined our understanding of how sperm PLCζ triggers Ca2 + oscillations and egg activation in mammals, while also discussing the nature of a potential “alternative” sperm factor. We summarise PLCζ localization in mammalian sperm, and the direct links observed between defective PLCζ protein in sperm and documented cases of male infertility. Finally, we postulate how this sperm protein can be used as a potential diagnostic marker, and also as a powerful therapeutic agent for treatment of certain types of male infertility due to egg activation failure or even in more general cases of male subfertility.
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Affiliation(s)
- Alaaeldin Saleh
- Member of QU Health, College of Medicine, Qatar University, Doha, Qatar
| | - Junaid Kashir
- College of Medicine, Alfaisal University, Riyadh, Saudi Arabia.,Department of Comparative Medicine, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia.,School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | | | | | - F Anthony Lai
- Member of QU Health, College of Medicine, Qatar University, Doha, Qatar.,Biomedical Research Center, Qatar University, Doha, Qatar
| | - Michail Nomikos
- Member of QU Health, College of Medicine, Qatar University, Doha, Qatar
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14
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Abstract
Phospholipase C (PLC) family members constitute a family of diverse enzymes. Thirteen different family members have been cloned. These family members have unique structures that mediate various functions. Although PLC family members all appear to signal through the bi-products of cleaving phospholipids, it is clear that each family member, and at times each isoform, contributes to unique cellular functions. This chapter provides a review of the current literature on PLC. In addition, references have been provided for more in-depth information regarding areas that are not discussed including tyrosine kinase activation of PLC. Understanding the roles of the individual PLC enzymes, and their distinct cellular functions, will lead to a better understanding of the physiological roles of these enzymes in the development of diseases and the maintenance of homeostasis.
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15
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Mortimer D. The functional anatomy of the human spermatozoon: relating ultrastructure and function. Mol Hum Reprod 2019; 24:567-592. [PMID: 30215807 DOI: 10.1093/molehr/gay040] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 09/11/2018] [Indexed: 12/16/2022] Open
Abstract
The Internet, magazine articles, and even biomedical journal articles, are full of cartoons of spermatozoa that bear minimal resemblance to real spermatozoa, especially human spermatozoa, and this had led to many misconceptions about what spermatozoa look like and how they are constituted. This review summarizes the historical and current state of knowledge of mammalian sperm ultrastructure, with particular emphasis on and relevance to human spermatozoa, combining information obtained from a variety of electron microscopic (EM) techniques. Available information on the composition and configuration of the various ultrastructural components of the spermatozoon has been related to their mechanistic purpose and roles in the primary aspects of sperm function and fertilization: motility, hyperactivation, capacitation, the acrosome reaction and sperm-oocyte fusion.
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Affiliation(s)
- David Mortimer
- Oozoa Biomedical Inc., Caulfeild Village, West Vancouver, BC, Canada
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16
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Anifandis G, Michopoulos A, Daponte A, Chatzimeletiou K, Simopoulou M, Messini CI, Polyzos NP, Vassiou K, Dafopoulos K, Goulis DG. Artificial oocyte activation: physiological, pathophysiological and ethical aspects. Syst Biol Reprod Med 2018; 65:3-11. [DOI: 10.1080/19396368.2018.1516000] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- George Anifandis
- Department of Obstetrics and Gynecology, ART Unit, University of Thessaly, School of Health Sciences, Faculty of Medicine, Larisa, Greece
| | - Alexandros Michopoulos
- Unit of Reproductive Endocrinology, 1st Department of Obstetrics and Gynecology, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Alexandros Daponte
- Department of Obstetrics and Gynecology, ART Unit, University of Thessaly, School of Health Sciences, Faculty of Medicine, Larisa, Greece
| | - Katerina Chatzimeletiou
- Unit of Human Reproduction, 1st Department of Obstetrics and Gynecology, Aristotle University Medical School, Papageorgiou General Hospital, Thessaloniki, Greece
| | - Mara Simopoulou
- Department of Physiology, Kapodistrian University of Athens, School of Health Sciences, Faculty of Medicine, Athens, Greece
| | - Christina I. Messini
- Department of Obstetrics and Gynecology, ART Unit, University of Thessaly, School of Health Sciences, Faculty of Medicine, Larisa, Greece
| | - Nikolas P. Polyzos
- Vrije Universiteit Brussel, Brussels, Belgium
- Universitair Ziekenhuis Brussel, Brussels, Belgium
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Katerina Vassiou
- Department of Anatomy, University of Thessaly, School of Health Sciences, Faculty of Medicine, Larisa, Greece
| | - Konstantinos Dafopoulos
- Department of Obstetrics and Gynecology, ART Unit, University of Thessaly, School of Health Sciences, Faculty of Medicine, Larisa, Greece
| | - Dimitrios G. Goulis
- Unit of Reproductive Endocrinology, 1st Department of Obstetrics and Gynecology, Aristotle University of Thessaloniki, Thessaloniki, Greece
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17
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Azad N, Nazarian H, Ghaffari Novin M, Masteri Farahani R, Piryaei A, Heidari MH, Abdollahpour Alitappeh M. Oligoasthenoteratozoospermic (OAT) men display altered phospholipase C ζ (PLCζ) localization and a lower percentage of sperm cells expressing PLCζ and post-acrosomal sheath WW domain-binding protein (PAWP). Bosn J Basic Med Sci 2018; 18:178-184. [PMID: 28954204 DOI: 10.17305/bjbms.2017.2208] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 07/31/2017] [Accepted: 08/01/2017] [Indexed: 01/31/2023] Open
Abstract
Oligoasthenoteratozoospermia (OAT) is demonstrated to be one of the most common causes of male subfertility. Phospholipase C ζ (PLCζ), a sperm-specific protein, is considered to be one of the sperm-borne oocyte activating factors (SOAFs), which play a vital role in fertilization. The post-acrosomal sheath WW domain-binding protein (PAWP) is another candidate for SOAF. The aim of this study was to compare the PLCζ localization patterns and percentage of PLCζ- and PAWP-positive sperm cells in patients with OAT and fertile men with normozoospermia. A total of 40 men included in this study were classified into two groups: OAT (n = 25) and control group (n = 15). Semen samples were collected and analyzed using conventional semen analysis according to the World Health Organization guidelines. The percentage of PLCζ- and PAWP-positive sperm cells and localization patterns of PLCζ were evaluated using immunofluorescence staining. The mean percentage of sperm cells expressing PAWP and PLCζ was significantly lower in OAT compared to control group (52.8 ± 4.2 vs. 76.8 ± 5 and 63.4 ± 3.5 vs. 86.7 ± 2.1, respectively). In addition, statistically significant differences were found with regard to the PLCζ localization patterns, including equatorial, acrosomal + equatorial, and equatorial + post-acrosomal pattern, between the two groups (p < 0.01). The present study showed a lower percentage of sperm cells expressing PLCζ and PAWP, as well as altered localization patterns of PLCζ in men with OAT. Given the role of PLCζ and PAWP in fertilization, as two major candidates for SOAFs, our findings indicate that PLCζ and PAWP impairments may be one of the possible etiologies of decreased fertility in OAT.
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Affiliation(s)
- Nahid Azad
- Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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18
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Sperm-borne phospholipase C zeta-1 ensures monospermic fertilization in mice. Sci Rep 2018; 8:1315. [PMID: 29358633 PMCID: PMC5778054 DOI: 10.1038/s41598-018-19497-6] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 01/03/2018] [Indexed: 12/23/2022] Open
Abstract
Sperm entry in mammalian oocytes triggers intracellular Ca2+ oscillations that initiate resumption of the meiotic cell cycle and subsequent activations. Here, we show that phospholipase C zeta 1 (PLCζ1) is the long-sought sperm-borne oocyte activation factor (SOAF). Plcz1 gene knockout (KO) mouse spermatozoa fail to induce Ca2+ changes in intracytoplasmic sperm injection (ICSI). In contrast to ICSI, Plcz1 KO spermatozoa induced atypical patterns of Ca2+ changes in normal fertilizations, and most of the fertilized oocytes ceased development at the 1–2-cell stage because of oocyte activation failure or polyspermy. We further discovered that both zona pellucida block to polyspermy (ZPBP) and plasma membrane block to polyspermy (PMBP) were delayed in oocytes fertilized with Plcz1 KO spermatozoa. With the observation that polyspermy is rare in astacin-like metalloendopeptidase (Astl) KO female oocytes that lack ZPBP, we conclude that PMPB plays more critical role than ZPBP in vivo. Finally, we obtained healthy pups from male mice carrying human infertile PLCZ1 mutation by single sperm ICSI supplemented with Plcz1 mRNA injection. These results suggest that mammalian spermatozoa have a primitive oocyte activation mechanism and that PLCζ1 is a SOAF that ensures oocyte activation steps for monospermic fertilization in mammals.
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19
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Freour T, Barragan M, Torra-Massana M, Ferrer-Vaquer A, Vassena R. Is there an association between PAWP/WBP2NL sequence, expression, and distribution in sperm cells and fertilization failures in ICSI cycles? Mol Reprod Dev 2018; 85:163-170. [PMID: 29271520 DOI: 10.1002/mrd.22950] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 12/11/2017] [Indexed: 02/01/2023]
Abstract
Successful fertilization in mammals depends on the sperm's ability to initiate intracellular Ca2+ oscillations in the egg, a phenomenon that is elicited by Sperm-oocyte activating factors (SOAFs), whose quantitative and/or qualitative defect might result in fertilization failure. One such proposed factor is Post-acrosomal WW domain-binding protein (PAWP/WBP2NL), although its ability to activate human oocytes has been questioned and its implication in human fertilization failure remains unknown. Here, we sought to determine if PAWP/WBP2NL expression and distribution in sperm cells associate with low/complete fertilization failure in males participating in intracytoplasmic sperm injection (ICSI) cycles. This prospective study was conducted on eight couples referred for elective ICSI with either the woman's own (n = 4) or a donor eggs (n = 4). Eight sperm donor samples used in ICSI, which resulted in normal fertilization rates, were used as the control group. For each male patient and donor sperm, PAWP/WBP2NL sequence, protein expression, and cellular distribution were analyzed by PCR amplification-sequencing, Western blot, and immunofluorescence, respectively. PAWP/WBP2NL was present in all samples, and no significant differences were detected between patients with fertilization failure and donors in sequence variants or mean protein expression, or in the proportion of PAWP/WBP2NL-positive sperm. In conclusion, no clear association between PAWP/WBP2NL protein expression in sperm and fertilization outcome in ICSI were observed from this cohort.
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Affiliation(s)
- Thomas Freour
- Clínica Eugin, Barcelona, Spain.,Service de médecine de la reproduction, CHU de Nantes, Nantes, France.,Inserm UMR1064-ITUN, Nantes, France.,Faculté de médecine, Université de Nantes, Nantes, France
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20
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Kashir J, Nomikos M, Lai FA. Phospholipase C zeta and calcium oscillations at fertilisation: The evidence, applications, and further questions. Adv Biol Regul 2017; 67:148-162. [PMID: 29108881 DOI: 10.1016/j.jbior.2017.10.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 10/25/2017] [Accepted: 10/25/2017] [Indexed: 12/26/2022]
Abstract
Oocyte activation is a fundamental event at mammalian fertilisation, initiated by a series of characteristic calcium (Ca2+) oscillations in mammals. This characteristic pattern of Ca2+ release is induced in a species-specific manner by a sperm-specific enzyme termed phospholipase C zeta (PLCζ). Reduction or absence of functional PLCζ within sperm underlies male factor infertility in humans, due to mutational inactivation or abrogation of PLCζ protein expression. Underlying such clinical implications, a significant body of evidence has now been accumulated that has characterised the unique biochemical and biophysical properties of this enzyme, further aiding the unique clinical opportunities presented. Herein, we present and discuss evidence accrued over the past decade and a half that serves to support the identity of PLCζ as the mammalian sperm factor. Furthermore, we also discuss the potential novel avenues that have yet to be examined regarding PLCζ mechanism of action in both the oocyte, and the sperm. Finally, we discuss the advances that have been made regarding the clinical therapeutic and diagnostic applications of PLCζ in potentially treating male infertility as a result of oocyte activation deficiency (OAD), and also possibly more general cases of male subfertility.
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Affiliation(s)
- Junaid Kashir
- College of Biomedical & Life Sciences, School of Biosciences, Cardiff University, Cardiff, UK; Alfaisal University, College of Medicine, Riyadh, Saudi Arabia; King Faisal Specialist Hospital & Research Center, Department of Comparative Medicine, Riyadh, Saudi Arabia.
| | - Michail Nomikos
- College of Medicine, Member of QU Health, Qatar University, PO Box 2713, Doha, Qatar
| | - F Anthony Lai
- College of Biomedical & Life Sciences, School of Biosciences, Cardiff University, Cardiff, UK; College of Medicine, Member of QU Health, Qatar University, PO Box 2713, Doha, Qatar.
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21
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The role and mechanism of action of sperm PLC-zeta in mammalian fertilisation. Biochem J 2017; 474:3659-3673. [PMID: 29061915 DOI: 10.1042/bcj20160521] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 09/14/2017] [Accepted: 09/18/2017] [Indexed: 12/26/2022]
Abstract
At mammalian fertilisation, the fundamental stimulus that triggers oocyte (egg) activation and initiation of early embryonic development is an acute rise of the intracellular-free calcium (Ca2+) concentration inside the egg cytoplasm. This essential Ca2+ increase comprises a characteristic series of repetitive Ca2+ oscillations, starting soon after sperm-egg fusion. Over the last 15 years, accumulating scientific and clinical evidence supports the notion that the physiological stimulus that precedes the cytosolic Ca2+ oscillations is a novel, testis-specific phospholipase C (PLC) isoform, known as PLC-zeta (PLCζ). Sperm PLCζ catalyses the hydrolysis of phosphatidylinositol 4,5-bisphosphate triggering cytosolic Ca2+ oscillations through the inositol 1,4,5-trisphosphate signalling pathway. PLCζ is the smallest known mammalian PLC isoform with the most elementary domain organisation. However, relative to somatic PLCs, the PLCζ isoform possesses a unique potency in stimulating Ca2+ oscillations in eggs that is attributed to its novel biochemical characteristics. In this review, we discuss the latest developments that have begun to unravel the vital role of PLCζ at mammalian fertilisation and decipher its unique mechanism of action within the fertilising egg. We also postulate the significant potential diagnostic and therapeutic capacity of PLCζ in alleviating certain types of male infertility.
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22
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Atabay EP, Tadeo RD, Atabay EC, Venturina EV, Fissore RA, Mingala CN. Molecular Characterization and Comparison of Phospholipase C zeta (PLCZ1) Gene Between Swamp (Bubalus carabanensis) and Riverine (Bubalus bubalis) Buffaloes: Its Implications and Future Perspectives. Anim Biotechnol 2017; 29:190-198. [PMID: 28799828 DOI: 10.1080/10495398.2017.1350689] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Phospholipase C zeta, a novel sperm-specific protein which is widely known to induce oocyte activation following fertilization, had already been characterized in various mammalian species, but not in water buffaloes thus far. The present study was conducted to initially characterize and compare the sequences of PLCZ1 gene of swamp and riverine buffaloes. Semen samples were collected; total RNA was extracted and reverse-transcribed. PLCZ1 cDNA was then amplified, and submitted for sequencing. Buffalo PLCZ1 gene yielded a sequence of 1905 base pair nucleotides translated into 634 bp amino acids. In general, the buffalo PLCZ1 gene was found to have high sequence identity with cattle and other domestic species. Similarly, significant residues and motifs in PLCZ1 gene sequence are found conserved in water buffaloes. However, there are variations in sequences identified between types of water buffaloes that may play a role in species-specific differences in terms of gene and protein expression, physiological mechanisms, and biological functions. The molecular information on buffalo PLCZ1 gene is highly valuable in subsequent works such as correlation studies on the identified gene variations with semen quality and fertility, and the development of biomarkers for bull fertility.
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Affiliation(s)
- Eufrocina P Atabay
- a Philippine Carabao Center, National Headquarters, Science City of Munoz , Nueva Ecija , Philippines
| | - Roseline D Tadeo
- a Philippine Carabao Center, National Headquarters, Science City of Munoz , Nueva Ecija , Philippines
| | - Edwin C Atabay
- b Philipine Carabao Center, Central Luzon State University, Science City of Munoz , Nueva Ecija , Philippines
| | - Emma V Venturina
- b Philipine Carabao Center, Central Luzon State University, Science City of Munoz , Nueva Ecija , Philippines
| | - Rafael A Fissore
- c Department of Veterinary and Animal Sciences , University of Massachusetts , Amherst , Massachusetts , USA
| | - Claro N Mingala
- a Philippine Carabao Center, National Headquarters, Science City of Munoz , Nueva Ecija , Philippines
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23
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Freour T, Barragan M, Ferrer-Vaquer A, Rodríguez A, Vassena R. WBP2NL/PAWP mRNA and protein expression in sperm cells are not related to semen parameters, fertilization rate, or reproductive outcome. J Assist Reprod Genet 2017; 34:803-810. [PMID: 28444612 DOI: 10.1007/s10815-017-0902-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 03/05/2017] [Indexed: 02/04/2023] Open
Abstract
PURPOSE WBP2NL/PAWP, a protein found in the post-acrosomal region of mammalian spermatozoa, has been proposed as a sperm-borne oocyte-activating factor (SOAF) contributing to Ca2+ release within the oocyte and subsequent fertilization and embryo development. However, its relevance as either a diagnostic or a prognostic marker of fertilization failure has been questioned in the recent literature. We analyzed WBP2NL/PAWP gene and protein expression level and localization in patients without previous intracytoplasmic sperm injection (ICSI) cycles in order to assess its association with both sperm characteristics and ability to fertilize. METHODS Raw frozen-thawed semen samples from 33 couples referred for oocyte donation were included in the study during 2015. Relative protein expression versus α-tubulin (western blot, WB), proportion of post-acrosomal WBP2NL/PAWP-positive spermatozoa over the total number of sperm cells (immunofluorescence), and WBP2NL/PAWP gene expression (RT-qPCR) were analyzed and correlated with semen analysis parameters (number, motility, and morphology) and with reproductive outcomes. RESULTS WBP2NL/PAWP protein was expressed in all samples with high variability: relative protein expression (1.77 ± 0.8, range [0.4-3.7]), proportion of positive cells (49.6% ± 16.1, range [22-89]), and relative gene expression (7.3 ± 8.2). No significant correlation (R 2 < 0.1) was found between gene and protein expression, neither between WBP2NL/PAWP gene or protein expression, and fertilization rate or other reproductive outcomes (i.e., pregnancy). In contrast, we found significant correlation between sperm morphology and WBP2NL/PAWP semiquantitative analysis in WB (r = -0.42, p < 0.05) and for sperm motility and WBP2NL/PAWP expression in IF (r = 0.52, p < 0.05). CONCLUSION Taken into account that WBP2NL/PAWP gene and protein levels and distribution did not correlate with fertilization rates, this study questions the interest of WBP2NL/PAWP protein and gene expression analysis in sperm cells as a prognostic factor for the outcome of ICSI cycles. Larger studies focusing on WBP2NL/PAWP protein and gene expression are needed in order to evaluate the role of WBP2NL/PAWP as a prognostic factor for ART.
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Affiliation(s)
- T Freour
- Clínica Eugin, Traversera de les Corts, 322 - 08029, Barcelona, Spain.,Service de médecine de la reproduction, CHU de Nantes, 44093, Nantes, France.,Inserm UMR1064 - ITUN, 44000, Nantes, France.,Faculté de médecine, Université de Nantes, 44000, Nantes, France
| | - M Barragan
- Clínica Eugin, Traversera de les Corts, 322 - 08029, Barcelona, Spain
| | - A Ferrer-Vaquer
- Clínica Eugin, Traversera de les Corts, 322 - 08029, Barcelona, Spain
| | - A Rodríguez
- Clínica Eugin, Traversera de les Corts, 322 - 08029, Barcelona, Spain
| | - Rita Vassena
- Clínica Eugin, Traversera de les Corts, 322 - 08029, Barcelona, Spain.
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24
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Male infertility-linked point mutation reveals a vital binding role for the C2 domain of sperm PLCζ. Biochem J 2017; 474:1003-1016. [PMID: 28270562 DOI: 10.1042/bcj20161057] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 01/05/2017] [Accepted: 01/20/2017] [Indexed: 12/14/2022]
Abstract
Sperm-specific phospholipase C zeta (PLCζ) is widely considered to be the physiological stimulus that evokes intracellular calcium (Ca2+) oscillations that are essential for the initiation of egg activation during mammalian fertilisation. A recent genetic study reported a male infertility case that was directly associated with a point mutation in the PLCζ C2 domain, where an isoleucine residue had been substituted with a phenylalanine (I489F). Here, we have analysed the effect of this mutation on the in vivo Ca2+ oscillation-inducing activity and the in vitro biochemical properties of human PLCζ. Microinjection of cRNA or recombinant protein corresponding to PLCζI489F mutant at physiological concentrations completely failed to cause Ca2+ oscillations and trigger development. However, this infertile phenotype could be effectively rescued by microinjection of relatively high (non-physiological) amounts of recombinant mutant PLCζI489F protein, leading to Ca2+ oscillations and egg activation. Our in vitro biochemical analysis suggested that the PLCζI489F mutant displayed similar enzymatic properties, but dramatically reduced binding to PI(3)P and PI(5)P-containing liposomes compared with wild-type PLCζ. Our findings highlight the importance of PLCζ at fertilisation and the vital role of the C2 domain in PLCζ function, possibly due to its novel binding characteristics.
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25
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Yeste M, Jones C, Amdani SN, Coward K. Oocyte Activation and Fertilisation: Crucial Contributors from the Sperm and Oocyte. Results Probl Cell Differ 2017; 59:213-239. [PMID: 28247051 DOI: 10.1007/978-3-319-44820-6_8] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This chapter intends to summarise the importance of sperm- and oocyte-derived factors in the processes of sperm-oocyte binding and oocyte activation. First, we describe the initial interaction between sperm and the zona pellucida, with particular regard to acrosome exocytosis. We then describe how sperm and oocyte membranes fuse, with special reference to the discovery of the sperm protein IZUMO1 and its interaction with the oocyte membrane receptor JUNO. We then focus specifically upon oocyte activation, the fundamental process by which the oocyte is alleviated from metaphase II arrest by a sperm-soluble factor. The identity of this sperm factor has been the source of much debate recently, although mounting evidence, from several different laboratories, provides strong support for phospholipase C ζ (PLCζ), a sperm-specific phospholipase. Herein, we discuss the evidence in support of PLCζ and evaluate the potential role of other candidate proteins, such as post-acrosomal WW-binding domain protein (PAWP/WBP2NL). Since the cascade of downstream events triggered by the sperm-borne oocyte activation factor heavily relies upon specialised cellular machinery within the oocyte, we also discuss the critical role of oocyte-borne factors, such as the inositol trisphosphate receptor (IP3R), protein kinase C (PKC), store-operated calcium entry (SOCE) and calcium/calmodulin-dependent protein kinase II (CaMKII), during the process of oocyte activation. In order to place the implications of these various factors and processes into a clinical context, we proceed to describe their potential association with oocyte activation failure and discuss how clinical techniques such as the in vitro maturation of oocytes may affect oocyte activation ability. Finally, we contemplate the role of artificial oocyte activating agents in the clinical rescue of oocyte activation deficiency and discuss options for more endogenous alternatives.
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Affiliation(s)
- Marc Yeste
- Unit of Cell Biology, Department of Biology, Faculty of Sciences, University of Girona, C/ Maria Aurèlia Campany, 69, Campus Montilivi, E-17071, Girona, Spain. .,Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Level 3, Women's Centre, John Radcliffe Hospital, Headington, Oxford, UK.
| | - Celine Jones
- Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Level 3, Women's Centre, John Radcliffe Hospital, Headington, Oxford, UK
| | - Siti Nornadhirah Amdani
- Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Level 3, Women's Centre, John Radcliffe Hospital, Headington, Oxford, UK
| | - Kevin Coward
- Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Level 3, Women's Centre, John Radcliffe Hospital, Headington, Oxford, UK
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26
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Kashir J, Buntwal L, Nomikos M, Calver BL, Stamatiadis P, Ashley P, Vassilakopoulou V, Sanders D, Knaggs P, Livaniou E, Bunkheila A, Swann K, Lai FA. Antigen unmasking enhances visualization efficacy of the oocyte activation factor, phospholipase C zeta, in mammalian sperm. Mol Hum Reprod 2016; 23:54-67. [PMID: 27932551 DOI: 10.1093/molehr/gaw073] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 09/23/2016] [Accepted: 11/21/2016] [Indexed: 12/14/2022] Open
Abstract
STUDY QUESTION Is it possible to improve clinical visualization of phospholipase C zeta (PLCζ) as a diagnostic marker of sperm oocyte activation capacity and male fertility? SUMMARY ANSWER Poor PLCζ visualization efficacy using current protocols may be due to steric or conformational occlusion of native PLCζ, hindering antibody access, and is significantly enhanced using antigen unmasking/retrieval (AUM) protocols. WHAT IS KNOWN ALREADY Mammalian oocyte activation is mediated via a series of intracellular calcium (Ca2+) oscillations induced by sperm-specific PLCζ. PLCζ represents not only a potential clinical therapeutic in cases of oocyte activation deficiency but also a diagnostic marker of sperm fertility. However, there are significant concerns surrounding PLCζ antibody specificity and detection protocols. STUDY DESIGN, SIZE DURATION Two PLCζ polyclonal antibodies, with confirmed PLCζ specificity, were employed in mouse, porcine and human sperm. Experiments evaluated PLCζ visualization efficacy, and whether AUM improved this. Antibodies against two sperm-specific proteins [post-acrosomal WW-binding protein (PAWP) and acrosin] were used as controls. PARTICIPANTS/MATERIALS, SETTING, METHODS Aldehyde- and methanol-fixed sperm were subject to immunofluorescence analysis following HCl exposure (pH = 0.1-0.5), acid Tyrode's solution exposure (pH = 2.5) or heating in 10 mM sodium citrate solution (pH = 6.0). Fluorescence intensity of at least 300 cells was recorded for each treatment, with three independent repeats. MAIN RESULTS AND THE ROLE OF CHANCE Despite high specificity for native PLCζ following immunoblotting using epitope-specific polyclonal PLCζ antibodies in mouse, porcine and human sperm, immunofluorescent visualization efficacy was poor. In contrast, sperm markers PAWP and acrosin exhibited relatively impressive results. All methods of AUM on aldehyde-fixed sperm enhanced visualization efficacy for PLCζ compared to visualization efficacy before AUM (P < 0.05 for all AUM interventions), but exerted no significant change upon PAWP or acrosin immunofluorescence following AUM. All methods of AUM enhanced PLCζ visualization efficacy in mouse and human methanol-fixed sperm compared to without AUM (P < 0.05 for all AUM interventions), while no significant change was observed in methanol-fixed porcine sperm before and after. In the absence of aldehyde-induced cross-linkages, such results suggest that poor PLCζ visualization efficacy may be due to steric or conformational occlusion of native PLCζ, hindering antibody access. Importantly, examination of sperm from individual donors revealed that AUM differentially affects observable PLCζ fluorescence, and the proportion of sperm exhibiting detectable PLCζ fluorescence in sperm from different males. LIMITATIONS, REASONS FOR CAUTION Direct correlation of fertility outcomes with the level of PLCζ in the sperm samples studied was not available. Such analyses would be required in future to determine whether the improved methodology for PLCζ visualization we propose would indeed reflect fertility status. WIDER IMPLICATIONS OF THE FINDINGS We propose that AUM alters conformational interactions to enhance PLCζ epitope availability and visualization efficacy, supporting prospective application of AUM to reduce misinterpretation in clinical diagnosis of PLCζ-linked male infertility. Our current results suggest that it is perhaps prudent that previous studies investigating links between PLCζ and fertility parameters are re-examined in the context of AUM, and may pave the way for future work to answer significant questions such as how PLCζ appears to be kept in an inactive form in the sperm. LARGE SCALE DATA Not applicable. STUDY FUNDING/COMPETING INTERESTS J.K. is supported by a Health Fellowship award from the National Institute for Social Care and Health Research (NISCHR). M.N. is supported by a Marie Curie Intra-European Research Fellowship award. This work was also partly funded by a research grant from Cook Medical Technologies LLC. There are no competing financial interests to declare.
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Affiliation(s)
- Junaid Kashir
- College of Biomedical and Life Sciences, Schools of Bioscience & Medicine, Cardiff University, Cardiff, UK .,Alfaisal University, College of Medicine, Riyadh, Saudi Arabia.,King Faisal Specialist Hospital & Research Center, Department of Comparative Medicine, Riyadh, Saudi Arabia
| | - Luke Buntwal
- College of Biomedical and Life Sciences, Schools of Bioscience & Medicine, Cardiff University, Cardiff, UK
| | - Michail Nomikos
- Qatar University, College of Medicine, PO BOX 2713, Doha, Qatar.,School of Medicine, Cardiff University, UK
| | - Brian L Calver
- College of Biomedical and Life Sciences, Schools of Bioscience & Medicine, Cardiff University, Cardiff, UK
| | - Panagiotis Stamatiadis
- College of Biomedical and Life Sciences, Schools of Bioscience & Medicine, Cardiff University, Cardiff, UK
| | - Peter Ashley
- Wales Fertility Institute, University Hospital Wales, Cardiff, UK
| | | | - David Sanders
- Wales Fertility Institute, University Hospital Wales, Cardiff, UK
| | - Paul Knaggs
- Wales Fertility Institute, University Hospital Wales, Cardiff, UK
| | - Evangelia Livaniou
- National Center for Scientific Research 'Demokritos', 15310 Aghia Paraskevi, Greece
| | - Adnan Bunkheila
- Wales Fertility Institute, University Hospital Wales, Cardiff, UK
| | - Karl Swann
- College of Biomedical and Life Sciences, Schools of Bioscience & Medicine, Cardiff University, Cardiff, UK
| | - F Anthony Lai
- College of Biomedical and Life Sciences, Schools of Bioscience & Medicine, Cardiff University, Cardiff, UK
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27
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Abstract
A series of intracellular oscillations in the free cytosolic Ca(2+) concentration is responsible for activating mammalian eggs at fertilization, thus initiating embryo development. It has been proposed that the sperm causes these Ca(2+) oscillations after membrane fusion by delivering a soluble protein into the egg cytoplasm. We previously identified sperm-specific phospholipase C (PLC)-ζ as a protein that can trigger the same pattern of Ca(2+) oscillations in eggs seen at fertilization. PLCζ appears to be the elusive sperm factor mediating egg activation in mammals. It has potential therapeutic use in infertility treatments to improve the rate of egg activation and early embryo development after intra-cytoplasmic sperm injection. A stable form of recombinant human PLCζ could be a prototype for use in such in vitro fertilization (IVF) treatments. We do not yet understand exactly how PLCζ causes inositol 1,4,5-trisphosphate (InsP3) production in eggs. Sperm PLCζ is distinct among mammalian PI-specific PLCs in that it is far more potent in triggering Ca(2+) oscillations in eggs than other PLCs, but it lacks a PH domain that would otherwise be considered essential for binding to the phosphatidylinositol 4,5-bisphosphate (PIP2) substrate. PLCζ is also unusual in that it does not appear to interact with or hydrolyse plasma membrane PIP2. We consider how other regions of PLCζ may mediate its binding to PIP2 in eggs and how interaction of PLCζ with egg-specific factors could enable the hydrolysis of internal sources of PIP2.
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28
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Sanders JR, Swann K. Molecular triggers of egg activation at fertilization in mammals. Reproduction 2016; 152:R41-50. [PMID: 27165049 DOI: 10.1530/rep-16-0123] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 05/09/2016] [Indexed: 01/15/2023]
Abstract
In mammals, the sperm activates the development of the egg by triggering a series of oscillations in the cytosolic-free Ca(2+) concentration (Ca(2+) i). The sperm triggers these cytosolic Ca(2+i) oscillations after sperm-egg membrane fusion, as well as after intracytoplasmic sperm injection (ICSI). These Ca(2+) i oscillations are triggered by a protein located inside the sperm. The identity of the sperm protein has been debated over many years, but all the repeatable data now suggest that it is phospholipase Czeta (PLCζ). The main downstream target of Ca(2+) i oscillations is calmodulin-dependent protein kinase II (CAMKII (CAMK2A)), which phosphorylates EMI2 and WEE1B to inactivate the M-phase promoting factor protein kinase activity (MPF) and this ultimately triggers meiotic resumption. A later decline in the activity of mitogen-activated protein kinase (MAPK) then leads to the completion of activation which is marked by the formation of pronuclei and entry into interphase of the first cell cycle. The early cytosolic Ca(2+) increases also trigger exocytosis via a mechanism that does not involve CAMKII. We discuss some recent developments in our understanding of these triggers for egg activation within the framework of cytosolic Ca(2+) signaling.
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Affiliation(s)
| | - Karl Swann
- School of BiosciencesCardiff University, Cardiff, UK
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29
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Tavalaee M, Nasr-Esfahani MH. Expression profile ofPLCζ,PAWP,andTR-KITin association with fertilization potential, embryo development, and pregnancy outcomes in globozoospermic candidates for intra-cytoplasmic sperm injection and artificial oocyte activation. Andrology 2016; 4:850-6. [DOI: 10.1111/andr.12179] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 02/01/2016] [Accepted: 02/03/2016] [Indexed: 01/16/2023]
Affiliation(s)
- M. Tavalaee
- Department of Reproductive Biotechnology; Reproductive Biomedicine Research Center; Royan Institute for Biotechnology, ACECR; Isfahan Iran
| | - M. H. Nasr-Esfahani
- Department of Reproductive Biotechnology; Reproductive Biomedicine Research Center; Royan Institute for Biotechnology, ACECR; Isfahan Iran
- Isfahan Fertility and Infertility Center; Isfahan Iran
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30
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Escoffier J, Lee HC, Yassine S, Zouari R, Martinez G, Karaouzène T, Coutton C, Kherraf ZE, Halouani L, Triki C, Nef S, Thierry-Mieg N, Savinov SN, Fissore R, Ray PF, Arnoult C. Homozygous mutation of PLCZ1 leads to defective human oocyte activation and infertility that is not rescued by the WW-binding protein PAWP. Hum Mol Genet 2016; 25:878-91. [PMID: 26721930 PMCID: PMC4754041 DOI: 10.1093/hmg/ddv617] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 12/06/2015] [Accepted: 12/17/2015] [Indexed: 11/13/2022] Open
Abstract
In mammals, sperm-oocyte fusion initiates Ca(2+) oscillations leading to a series of events called oocyte activation, which is the first stage of embryo development. Ca(2+) signaling is elicited by the delivery of an oocyte-activating factor by the sperm. A sperm-specific phospholipase C (PLCZ1) has emerged as the likely candidate to induce oocyte activation. Recently, PAWP, a sperm-born tryptophan domain-binding protein coded by WBP2NL, was proposed to serve the same purpose. Here, we studied two infertile brothers exhibiting normal sperm morphology but complete fertilization failure after intracytoplasmic sperm injection. Whole exomic sequencing evidenced a missense homozygous mutation in PLCZ1, c.1465A>T; p.Ile489Phe, converting Ile 489 into Phe. We showed the mutation is deleterious, leading to the absence of the protein in sperm, mislocalization of the protein when injected in mouse GV and MII oocytes, highly abnormal Ca(2+) transients and early embryonic arrest. Altogether these alterations are consistent with our patients' sperm inability to induce oocyte activation and initiate embryo development. In contrast, no deleterious variants were identified in WBP2NL and PAWP presented normal expression and localization. Overall we demonstrate in humans, the absence of PLCZ1 alone is sufficient to prevent oocyte activation irrespective of the presence of PAWP. Additionally, it is the first mutation located in the C2 domain of PLCZ1, a domain involved in targeting proteins to cell membranes. This opens the door to structure-function studies to identify the conserved amino acids of the C2 domain that regulate the targeting of PLCZ1 and its selectivity for its lipid substrate(s).
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Affiliation(s)
- Jessica Escoffier
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland
| | | | - Sandra Yassine
- Université Grenoble Alpes, Grenoble, F-38000, Grenoble, France, Institut Albert Bonniot, INSERM U823, La Tronche F-38700, France
| | - Raoudha Zouari
- Polyclinique les Jasmins, Centre d'Aide Médicale à la Procréation, Centre Urbain Nord, 1003 Tunis, Tunisia
| | - Guillaume Martinez
- Université Grenoble Alpes, Grenoble, F-38000, Grenoble, France, Institut Albert Bonniot, INSERM U823, La Tronche F-38700, France
| | - Thomas Karaouzène
- Université Grenoble Alpes, Grenoble, F-38000, Grenoble, France, Institut Albert Bonniot, INSERM U823, La Tronche F-38700, France
| | - Charles Coutton
- Université Grenoble Alpes, Grenoble, F-38000, Grenoble, France, CHU de Grenoble, UF de Génétique Chromosomique, Grenoble F-38000, France
| | - Zine-Eddine Kherraf
- Université Grenoble Alpes, Grenoble, F-38000, Grenoble, France, Institut Albert Bonniot, INSERM U823, La Tronche F-38700, France
| | - Lazhar Halouani
- Polyclinique les Jasmins, Centre d'Aide Médicale à la Procréation, Centre Urbain Nord, 1003 Tunis, Tunisia
| | - Chema Triki
- Clinique Hannibal, Centre d'AMP, les berges du lac, 1053 Tunis, Tunisia
| | - Serge Nef
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland
| | - Nicolas Thierry-Mieg
- Université Grenoble Alpes, Grenoble, F-38000, Grenoble, France, Laboratoire TIMC-IMAG, UMR CNRS 5525, Grenoble F-38000, France and
| | - Sergey N Savinov
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA 01003, USA
| | | | - Pierre F Ray
- Université Grenoble Alpes, Grenoble, F-38000, Grenoble, France, Institut Albert Bonniot, INSERM U823, La Tronche F-38700, France, CHU de Grenoble, UF de Biochimie et Génétique Moléculaire, Grenoble F-38000, France
| | - Christophe Arnoult
- Université Grenoble Alpes, Grenoble, F-38000, Grenoble, France, Institut Albert Bonniot, INSERM U823, La Tronche F-38700, France,
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31
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Machaty Z. Signal transduction in mammalian oocytes during fertilization. Cell Tissue Res 2016; 363:169-183. [PMID: 26453398 PMCID: PMC4700098 DOI: 10.1007/s00441-015-2291-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 08/28/2015] [Indexed: 01/22/2023]
Abstract
Mammalian embryo development begins when the fertilizing sperm triggers a series of elevations in the oocyte's intracellular free Ca(2+) concentration. The elevations are the result of repeated release and re-uptake of Ca(2+) stored in the smooth endoplasmic reticulum. Ca(2+) release is primarily mediated by the phosphoinositide signaling system of the oocyte. The system is stimulated when the sperm causes the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2) into inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG); IP3 then binds its receptor on the surface of the endoplasmic reticulum that induces Ca(2+) release. The manner in which the sperm generates IP3, the Ca(2+) mobilizing second messenger, has been the subject of extensive research for a long time. The sperm factor hypothesis has eventually gained general acceptance, according to which it is a molecule from the sperm that diffuses into the ooplasm and stimulates the phosphoinositide cascade. Much evidence now indicates that the sperm-derived factor is phospholipase C-zeta (PLCζ) that cleaves PIP2 and generates IP3, eventually leading to oocyte activation. A recent addition to the candidate sperm factor list is the post-acrosomal sheath WW domain-binding protein (PAWP), whose role at fertilization is currently under debate. Ca(2+) influx across the plasma membrane is also important as, in the absence of extracellular Ca(2+), the oscillations run down prematurely. In pig oocytes, the influx that sustains the oscillations seems to be regulated by the filling status of the stores, whereas in the mouse other mechanisms might be involved. This work summarizes the current understanding of Ca(2+) signaling in mammalian oocytes.
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Affiliation(s)
- Zoltan Machaty
- Department of Animal Sciences, Purdue University, 915 W. State Street, West Lafayette, IN, 47907, USA.
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32
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Amdani SN, Yeste M, Jones C, Coward K. Phospholipase C zeta (PLCζ) and male infertility: Clinical update and topical developments. Adv Biol Regul 2015; 61:58-67. [PMID: 26700242 DOI: 10.1016/j.jbior.2015.11.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 11/26/2015] [Accepted: 11/26/2015] [Indexed: 01/09/2023]
Abstract
The development of a mammalian embryo is initiated by a sequence of molecular events collectively referred to as 'oocyte activation' and regulated by the release of intracellular calcium in the ooplasm. Over the last decade, phospholipase C zeta (PLCζ), a sperm protein introduced into the oocyte upon gamete fusion, has gained almost universal acceptance as the protein factor responsible for initiating oocyte activation. A large body of consistent and reproducible evidence, from both biochemical and clinical settings, confers support for the role of PLCζ in this fundamental biological context, which has significant ramifications for the management of human male infertility. Oocyte activation deficiency (OAD) and total fertilisation failure (TFF) are known causes of infertility and have both been linked to abnormalities in the structure, expression, and localisation pattern of PLCζ in human sperm. Assisted oocyte activators (AOAs) represent the only therapeutic option available for OAD at present, although these agents have been the source of much debate recently, particularly with regard to their potential epigenetic effects upon the embryo. Consequently, there is much interest in the deployment of sensitive PLCζ assays as prognostic/diagnostic tests and human recombinant PLCζ protein as an alternative form of therapy. Although PLCζ deficiency has been directly linked to a cohort of infertile cases, we have yet to identify the specific causal mechanisms involved. While two genetic mutations have been identified which link defective PLCζ protein to an infertile phenotype, both were observed in the same patient, and have yet to be described in other patients. Consequently, some researchers are investigating the possibility that genetic variations in the form of single nucleotide polymorphisms (SNPs) could provide some explanation, especially since >6000 SNPs have been identified in the PLCζ gene. As yet, however, there is no consistent data to suggest that any of these SNPs influence the functional ability of PLCζ. Other laboratories appear to be focussing upon the PLCζ promoter, which is bi-directional and shared with the actin filament capping muscle Z-line alpha 3 gene (CAPZA3), or seeking to identify interacting proteins within the ooplasm. The aim of this review is to provide a synopsis of recent progress in the application of PLCζ in diagnostic and therapeutic medicine, to discuss our current understanding of how the functional ability of PLCζ might be controlled, and thus how PLCζ deficiency might arise, and finally, to consider the potential implications of alternative sperm protein candidates, such as post-acrosomal WW-domain binding protein (PAWP), which has caused much debate and confusion in the field over the last few years.
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Affiliation(s)
- Siti Nornadhirah Amdani
- Nuffield Department of Obstetrics & Gynaecology, Level 3, Women's Centre, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK; PAPRSB Institute of Health Sciences, Universiti Brunei Darussalam, Jalan Tunku Link, Gadong, Brunei Darussalam
| | - Marc Yeste
- Nuffield Department of Obstetrics & Gynaecology, Level 3, Women's Centre, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
| | - Celine Jones
- Nuffield Department of Obstetrics & Gynaecology, Level 3, Women's Centre, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
| | - Kevin Coward
- Nuffield Department of Obstetrics & Gynaecology, Level 3, Women's Centre, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK.
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Satouh Y, Nozawa K, Ikawa M. Sperm postacrosomal WW domain-binding protein is not required for mouse egg activation. Biol Reprod 2015; 93:94. [PMID: 26377222 DOI: 10.1095/biolreprod.115.131441] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 09/08/2015] [Indexed: 11/01/2022] Open
Abstract
To begin embryonic development, the zygote must resume the cell cycle correctly after stimulation by sperm-borne oocyte-activating factors (SOAFs). The postacrosomal WW domain-binding protein (PAWP) is one of the strongest SOAF candidates and is widely conserved among eutherian mammals. It has been reported that the microinjection of recombinant PAWP protein can trigger not only Ca(2+) oscillations in mammalian eggs but also intracellular Ca(2+) release in amphibian eggs. It was also suggested that PAWP is involved in the formation of high-quality spermatozoa. On the other hand, negligible SOAF activity for PAWP cRNA has also been reported. In this study, we generated PAWP null mice and examined the fertilizing ability of male mice. Electron microscopy showed no aberrant morphology in spermatogenesis. Intracytoplasmic injection of a single spermatozoon from the null mouse line showed that depletion of PAWP elicited no quantitative differences in Ca(2+) oscillations or in subsequent development of the embryos. We conclude that PAWP does not play an essential role in mouse fertilization.
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Affiliation(s)
- Yuhkoh Satouh
- Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Kaori Nozawa
- Research Institute for Microbial Diseases, Osaka University, Osaka, Japan Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Masahito Ikawa
- Research Institute for Microbial Diseases, Osaka University, Osaka, Japan Graduate School of Medicine, Osaka University, Osaka, Japan School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
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Yeste M, Jones C, Amdani SN, Patel S, Coward K. Oocyte activation deficiency: a role for an oocyte contribution? Hum Reprod Update 2015; 22:23-47. [DOI: 10.1093/humupd/dmv040] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 08/13/2015] [Indexed: 12/11/2022] Open
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