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Lorenz J, Eisenhardt C, Mittermair T, Kulle AE, Holterhus PM, Fobker M, Boenigk W, Nordhoff V, Behre HM, Strünker T, Brenker C. The sperm-specific K + channel Slo3 is inhibited by albumin and steroids contained in reproductive fluids. Front Cell Dev Biol 2024; 12:1275116. [PMID: 39310227 PMCID: PMC11413451 DOI: 10.3389/fcell.2024.1275116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 07/19/2024] [Indexed: 09/25/2024] Open
Abstract
To locate and fertilize the egg, sperm probe the varying microenvironment prevailing at different stages during their journey across the female genital tract. To this end, they are equipped with a unique repertoire of mostly sperm-specific proteins. In particular, the flagellar Ca2+ channel CatSper has come into focus as a polymodal sensor used by human sperm to register ligands released into the female genital tract. Here, we provide the first comprehensive study on the pharmacology of the sperm-specific human Slo3 channel, shedding light on its modulation by reproductive fluids and their constituents. We show that seminal fluid and contained prostaglandins and Zn2+ do not affect the channel, whereas human Slo3 is inhibited in a non-genomic fashion by diverse steroids as well as by albumin, which are released into the oviduct along with the egg. This indicates that not only CatSper but also Slo3 harbours promiscuous ligand-binding sites that can accommodate structurally diverse molecules, suggesting that Slo3 is involved in chemosensory signalling in human sperm.
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Affiliation(s)
- Johannes Lorenz
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany
| | - Clara Eisenhardt
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany
| | - Teresa Mittermair
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany
| | - Alexandra E. Kulle
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics, Christian-Albrechts-University, Kiel, Germany
| | - Paul Martin Holterhus
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics, Christian-Albrechts-University, Kiel, Germany
| | - Manfred Fobker
- Center for Laboratory Medicine, University Hospital, Münster, Germany
| | - Wolfgang Boenigk
- Max Planck Institute for Neurobiology of Behaviour—Caesar, Bonn, Germany
| | - Verena Nordhoff
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany
| | | | - Timo Strünker
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany
| | - Christoph Brenker
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany
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He Y, Wang B, Huang J, Zhang D, Yuan Y. Environmental pollutants and male infertility: Effects on CatSper. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 277:116341. [PMID: 38653022 DOI: 10.1016/j.ecoenv.2024.116341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 04/07/2024] [Accepted: 04/15/2024] [Indexed: 04/25/2024]
Abstract
Infertility is a growing health concern among many couples worldwide. Men account for half of infertility cases. CatSper, a sperm-specific Ca2+ channel, is expressed on the cell membrane of mammalian sperm. CatSper plays an important role in male fertility because it facilitates the entry of Ca2+ necessary for the rapid change in sperm motility, thereby allowing it to navigate the hurdles of the female reproductive tract and successfully locate the egg. Many pollutants present in the environment have been shown to affect the functions of CatSper and sperm, which is a matter of capital importance to understanding and solving male infertility issues. Environmental pollutants can act as partial agonists or inhibitors of CatSper or exhibit a synergistic effect. In this article, we briefly describe the structure, functions, and regulatory mechanisms of CatSper, and discuss the body of literature covering the effects of environmental pollutants on CatSper.
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Affiliation(s)
- Yuxin He
- Nanchang University Queen Mary School, Jiangxi Medical College of Nanchang University, Nanchang 330031, China
| | - Binhui Wang
- School of Basic Medical Sciences, Nanchang University, Nanchang 330006, China
| | - Jian Huang
- Clinical Medical Experimental Center, Nanchang University, Nanchang 330031, China; Jiangxi Provincial Key Laboratory of Reproductive Physiology and Pathology, Nanchang University, Nanchang 330006, China
| | - Dalei Zhang
- School of Basic Medical Sciences, Nanchang University, Nanchang 330006, China; Jiangxi Provincial Key Laboratory of Reproductive Physiology and Pathology, Nanchang University, Nanchang 330006, China
| | - Yangyang Yuan
- Clinical Medical Experimental Center, Nanchang University, Nanchang 330031, China; Jiangxi Provincial Key Laboratory of Reproductive Physiology and Pathology, Nanchang University, Nanchang 330006, China.
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3
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Thacharodi A, Hassan S, Acharya G, Vithlani A, Hoang Le Q, Pugazhendhi A. Endocrine disrupting chemicals and their effects on the reproductive health in men. ENVIRONMENTAL RESEARCH 2023; 236:116825. [PMID: 37544467 DOI: 10.1016/j.envres.2023.116825] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 07/26/2023] [Accepted: 08/02/2023] [Indexed: 08/08/2023]
Abstract
Endocrine Disrupting Chemicals (EDCs) are harmful compounds that enter the environment naturally or through anthropogenic activities and disrupt normal endocrine functions in humans, adversely affecting reproductive health. Among the most significant sources of EDC contaminants are the pharmaceutical, cosmetic, and packaging industries. EDCs have been identified to have a deteriorating effect on male reproductive system, as evidenced by the increasing number of male infertility cases. A large number of case studies have been published in which men exposed to EDCs experienced testicular cancer, undescended testicles, a decrease in serum testosterone levels, and poor semen quality. Furthermore, epidemiological evidence suggested a link between prenatal EDC exposure and cryptorchidism or undescended testicles, hypospadias, and decreased anogenital distance in infants. The majority of these findings, however, are incongruent due to the lack of long-term follow-up studies that would demonstrate EDCs to be associated with male reproductive disorders. This review aims to provide an overview on recent scientific progress on the association of EDCs to male reproductive health with special emphasis on its toxicity and possible mechanism of EDCs that disrupt male reproductive system.
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Affiliation(s)
- Aswin Thacharodi
- Dr. Thacharodi's Laboratories, Department of Research and Development, Puducherry, 605005, India
| | - Saqib Hassan
- Department of Biotechnology, School of Bio and Chemical Engineering, Sathyabama Institute of Science and Technology, Chennai, Tamil Nadu, 600119, India; American Society for Microbiology, Washington, 20036, USA
| | - Gururaj Acharya
- Department of Civil Engineering, NMAM Institute of Technology, NITTE (Deemed to be university), Karnataka, 574110, India
| | - Avadh Vithlani
- Department of Pulmonary Medicine, Post Graduate Institute of Medical Education and Research, Chandigarh, 160012, India
| | - Quynh Hoang Le
- School of Medicine and Pharmacy, Duy Tan University, Da Nang, Viet Nam; Institute of Research and Development, Duy Tan University, Da Nang, Viet Nam
| | - Arivalagan Pugazhendhi
- School of Medicine and Pharmacy, Duy Tan University, Da Nang, Viet Nam; Institute of Research and Development, Duy Tan University, Da Nang, Viet Nam.
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Ke S, Luo T. The Chemosensing Role of CatSper in Mammalian Sperm: An Updated Review. Curr Issues Mol Biol 2023; 45:6995-7010. [PMID: 37754226 PMCID: PMC10528052 DOI: 10.3390/cimb45090442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 08/19/2023] [Accepted: 08/21/2023] [Indexed: 09/28/2023] Open
Abstract
After sperm enter the female reproductive tract, the physicochemical and biochemical microenvironment undergoes significant changes. In particular, the large changes in various ions encountered by sperm may alter the physiology of sperm, ultimately compromising capacitation and fertilization. Thus, the rapid response to environmental variations is vital for sperm functions. For example, Calcium, the most crucial ion for sperm functions, enters into sperm via Ca2+ permeable ion channels. The cation channel of sperm (CatSper) is a sperm-specific, pH-sensitive, and Ca2+-permeable ion channel. It is responsible for the predominant Ca2+ entry in mammalian sperm and is involved in nearly every event of sperm to acquire fertilizing capability. In addition, CatSper also serves as a pivotal polymodal chemosensor in mammalian sperm by responding to multiple chemical cues. Physiological chemicals (such as progesterone, prostaglandins, β-defensins, and odorants) provoke Ca2+ entry into sperm by activating CatSper and thus triggering sperm functions. Additionally, synthetic and natural chemicals (such as medicines, endocrine disrupting chemicals, drugs of abuse, and antioxidants) affect sperm functions by regulating CatSper-dependent Ca2+ signaling. Therefore, understanding the interactions between CatSper and extracellular ligands sheds light on the mechanisms underlying male infertility and offers innovative diagnostic and treatment approaches. This underscores the importance of CatSper as a crucial regulatory target in male reproduction, linking sperm function with the extracellular environment. In conclusion, this review comprehensively summarizes the relevant studies describing the environmental factors that affect CatSper in humans and rodents.
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Affiliation(s)
- Sulun Ke
- Institute of Life Science, Nanchang University, Nanchang 330031, China;
- Queen Mary School, Medical College, Nanchang University, Nanchang 330031, China
| | - Tao Luo
- Institute of Life Science, Nanchang University, Nanchang 330031, China;
- Key Laboratory of Reproductive Physiology and Pathology in Jiangxi Province, Nanchang University, Nanchang 330006, China
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Wehrli L, Galdadas I, Voirol L, Smieško M, Cambet Y, Jaquet V, Guerrier S, Gervasio FL, Nef S, Rahban R. The action of physiological and synthetic steroids on the calcium channel CatSper in human sperm. Front Cell Dev Biol 2023; 11:1221578. [PMID: 37547474 PMCID: PMC10397409 DOI: 10.3389/fcell.2023.1221578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 06/19/2023] [Indexed: 08/08/2023] Open
Abstract
The sperm-specific channel CatSper (cation channel of sperm) controls the intracellular Ca2+ concentration ([Ca2+]i) and plays an essential role in sperm function. It is mainly activated by the steroid progesterone (P4) but is also promiscuously activated by a wide range of synthetic and physiological compounds. These compounds include diverse steroids whose action on the channel is so far still controversial. To investigate the effect of these compounds on CatSper and sperm function, we developed a high-throughput screening (HTS) assay to measure changes in [Ca2+]i in human sperm and screened 1,280 approved and off-patent drugs including 90 steroids from the Prestwick chemical library. More than half of the steroids tested (53%) induced an increase in [Ca2+]i and reduced the P4-induced Ca2+ influx in human sperm in a dose-dependent manner. Ten of the most potent steroids (activating and P4-inhibiting) were selected for a detailed analysis of their action on CatSper and their ability to act on sperm acrosome reaction (AR) and penetration in viscous media. We found that these steroids show an inhibitory effect on P4 but not on prostaglandin E1-induced CatSper activation, suggesting that they compete for the same binding site as P4. Pregnenolone, dydrogesterone, epiandrosterone, nandrolone, and dehydroepiandrosterone acetate (DHEA) were found to activate CatSper at physiologically relevant concentrations within the nanomolar range. Like P4, most tested steroids did not significantly affect the AR while stanozolol and estropipate slightly increased sperm penetration into viscous medium. Furthermore, using a hybrid approach integrating pharmacophore analysis and statistical modelling, we were able to screen in silico for steroids that can activate the channel and define the physicochemical and structural properties required for a steroid to exhibit agonist activity against CatSper. Overall, our results indicate that not only physiological but also synthetic steroids can modulate the activity of CatSper with varying potency and if bound to CatSper prior to P4, could impair the timely CatSper activation necessary for proper fertilization to occur.
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Affiliation(s)
- Lydia Wehrli
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland
- Swiss Centre for Applied Human Toxicology (SCAHT), Basel, Switzerland
| | - Ioannis Galdadas
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, Geneva, Switzerland
- School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland
| | - Lionel Voirol
- Research Center for Statistics, Geneva School of Economics and Management, University of Geneva, Geneva, Switzerland
| | - Martin Smieško
- Swiss Centre for Applied Human Toxicology (SCAHT), Basel, Switzerland
- Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland
| | - Yves Cambet
- Readers, Assay Development and Screening Unit (READS Unit), Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Vincent Jaquet
- Readers, Assay Development and Screening Unit (READS Unit), Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Stéphane Guerrier
- Research Center for Statistics, Geneva School of Economics and Management, University of Geneva, Geneva, Switzerland
- Faculty of Science, University of Geneva, Geneva, Switzerland
| | - Francesco Luigi Gervasio
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, Geneva, Switzerland
- School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland
- Department of Chemistry, University College London, London, United Kingdom
- Institute of Structural and Molecular Biology, University College London, London, United Kingdom
| | - Serge Nef
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland
- Swiss Centre for Applied Human Toxicology (SCAHT), Basel, Switzerland
| | - Rita Rahban
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland
- Swiss Centre for Applied Human Toxicology (SCAHT), Basel, Switzerland
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6
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Schuppe HC, Köhn FM. [Impact of lifestyle and environmental factors on male reproductive health]. UROLOGIE (HEIDELBERG, GERMANY) 2022; 61:1217-1228. [PMID: 36229540 DOI: 10.1007/s00120-022-01951-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/15/2022] [Indexed: 06/16/2023]
Abstract
The identification of potential environmental hazards is of clinical relevance for the diagnosis of male infertility. Knowledge about these factors will improve prevention of fertility disorders. Apart from drugs or factors related to lifestyle such as alcohol and tobacco smoke, various environmental and occupational agents, both chemical and physical, may impair male reproduction. Reproductive toxicity may evolve at the hypothalamic-pituitary, testicular, or posttesticular level; endpoints comprise deterioration of spermatogenesis and sperm function as well as endocrine disorders and sexual dysfunction. However, due to the complex regulation of the male reproductive system, information regarding single exogenous factors and their mechanisms of action in humans is limited. This is also due to the fact that extrapolation of results obtained from experimental animal or in vitro studies remains difficult. Nevertheless, the assessment of relevant exposures to reproductive toxicants should be carefully evaluated during diagnostic procedures of andrological patients.
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Affiliation(s)
- Hans-Christian Schuppe
- Klinik und Poliklinik für Urologie, Kinderurologie und Andrologie, Sektion Konservative Andrologie, Universitätsklinikum Gießen und Marburg GmbH - Standort Gießen, Justus-Liebig-Universität Gießen, Gaffkystr. 14, 35385, Gießen, Deutschland.
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7
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Escada-Rebelo S, Cristo MI, Ramalho-Santos J, Amaral S. Mitochondria-Targeted Compounds to Assess and Improve Human Sperm Function. Antioxid Redox Signal 2022; 37:451-480. [PMID: 34847742 DOI: 10.1089/ars.2021.0238] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Significance: Currently 10%-15% of couples in reproductive age face infertility issues. More importantly, male factor contributes to 50% of these cases (either alone or in combination with female causes). Among various reasons, impaired sperm function is the main cause for male infertility. Furthermore, mitochondrial dysfunction and oxidative stress due to increased reactive oxygen species (ROS) production, particularly of mitochondrial origin, are believed to be the main contributors. Recent Advances: Mitochondrial dysfunction, particularly due to increased ROS production, has often been linked to impaired sperm function/quality. For decades, different methods and approaches have been developed to assess mitochondrial features that might correlate with sperm functionality. This connection is now completely accepted, with mitochondrial functionality assessment used more commonly as a readout of sperm functionality. More recently, mitochondria-targeted compounds are on the frontline for both assessment and therapeutic approaches. Critical Issues: In this review, we summarize the current methods for assessing key mitochondrial parameters known to reflect sperm quality as well as therapeutic strategies using mitochondria-targeted antioxidants aiming to improve sperm function in various situations, particularly after sperm cryopreservation. Future Directions: Although more systematic research is needed, mitochondria-targeted compounds definitely represent a promising tool to assess as well as to protect and improve sperm function. Antioxid. Redox Signal. 37, 451-480.
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Affiliation(s)
- Sara Escada-Rebelo
- PhD Programme in Experimental Biology and Biomedicine, Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Biology of Reproduction and Stem Cell Group, Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,IIIUC - Institute for Interdisciplinary Research, Casa Costa Alemão, University of Coimbra, Coimbra, Portugal
| | - Maria Inês Cristo
- Biology of Reproduction and Stem Cell Group, Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - João Ramalho-Santos
- Biology of Reproduction and Stem Cell Group, Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Sandra Amaral
- Biology of Reproduction and Stem Cell Group, Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,IIIUC - Institute for Interdisciplinary Research, Casa Costa Alemão, University of Coimbra, Coimbra, Portugal
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8
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Birch MR, Johansen M, Skakkebæk NE, Andersson AM, Rehfeld A. In vitro investigation of endocrine disrupting effects of pesticides on Ca 2+-signaling in human sperm cells through actions on the sperm-specific and steroid-activated CatSper Ca 2+-channel. ENVIRONMENT INTERNATIONAL 2022; 167:107399. [PMID: 35853389 DOI: 10.1016/j.envint.2022.107399] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 06/30/2022] [Accepted: 07/05/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Ca2+-signaling controls sperm cell functions necessary for successful fertilization. Multiple endocrine disrupting chemicals have been found to interfere with normal Ca2+-signaling in human sperm cells through an activation of the sperm-specific CatSper Ca2+-channel, which is vital for normal male fertility. OBJECTIVES We investigated 53 pesticides for their ability to interfere with CatSper mediated Ca2+-signaling and function in human sperm cells. METHODS Effects of the pesticides on Ca2+-signaling in human sperm cells were evaluated using a Ca2+-fluorometric assay. Effects via CatSper were assessed using the specific CatSper inhibitor RU1968. Effects on human sperm function and viability were assessed using an image cytometry-based acrosome reaction assay and the modified Kremer's sperm-mucus penetration assay. RESULTS 28 of 53 pesticides were found to induce Ca2+-signals in human sperm cells at 10 µM. The majority of these 28 active pesticides induced Ca2+-signals through CatSper and interfered with subsequent Ca2+-signals induced by the two endogenous CatSper ligands progesterone and prostaglandin E1. Multiple active pesticides were found to affect Ca2+-mediated sperm functions and viability at 10 µM. Low nM dose mixtures of the active pesticides alone or in combination with other environmental chemicals were found to significantly induce Ca2+-signals and inhibit Ca2+-signals induced subsequently by progesterone and prostaglandin E1. CONCLUSIONS Our results show that pesticides, both alone and in low nM dose mixtures, interfere with normal Ca2+-signaling in human sperm cells in vitro in low nM concentrations. Biomonitoring of the active pesticides in relevant matrices such as blood and reproductive fluids is very limited and the effects of real time human pesticide exposure on human sperm cells and fertility thus remains largely unknown. To which extent human pesticide exposure affects the chances of a successful fertilization in humans in vivo needs further research.
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Affiliation(s)
- Michala R Birch
- Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Denmark; International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Rigshospitalet, University of Copenhagen, Denmark
| | - Mathias Johansen
- Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Denmark; International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Rigshospitalet, University of Copenhagen, Denmark
| | - Niels E Skakkebæk
- Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Denmark; International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Rigshospitalet, University of Copenhagen, Denmark
| | - Anna-Maria Andersson
- Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Denmark; International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Rigshospitalet, University of Copenhagen, Denmark
| | - Anders Rehfeld
- Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Denmark; International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Rigshospitalet, University of Copenhagen, Denmark.
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He Z, Xie M, Li QQ, Duan J, Lu X. Research Progress on the Microregulatory Mechanisms of Fertilization: A Review. In Vivo 2022; 36:2002-2013. [PMID: 36099087 PMCID: PMC9463889 DOI: 10.21873/invivo.12926] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/19/2022] [Accepted: 06/22/2022] [Indexed: 11/10/2022]
Abstract
The process of fertilization includes sperm capacitation, hyperactivation, an acrosome reaction and the release of acrosome enzymes, membrane fusion and channel formation, the release of the sperm nucleus, and gamete fusion. This process is closely related to the shape and vitality of the sperm, acrosome enzyme release, and the zona pellucida structure of the egg, as well as the opening and closing of various ion (e.g., calcium) channels, the regulation of signaling pathways such as cyclic adenosine monophosphate-protein kinase A, the release of progesterone, and the coupling of G-proteins. The interaction among multiple factors and their precise regulation give rise to multiple cascading regulatory processes. Problems with any factor will affect the success rate of fertilization. Recent studies have shown that with rapid societal development, the incidence of male infertility is increasing and occurs at younger ages. According to World Health Organization statistics, 15% of couples of childbearing ages have infertility problems, of which 50% are caused by male factors. Additionally, the cause of infertility cannot be identified in as many as 60% to 75% of male infertility patients. In this article, we review the research progress on the microregulation of fertilization and mechanisms underlying this process to identify causes and develop novel prevention and treatment strategies for male infertility.
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Affiliation(s)
- Zubin He
- Department of Urology, People's Hospital of Beiliu, Beiliu, P. R. China
| | - Mei Xie
- Department of Urology, People's Hospital of Beiliu, Beiliu, P. R. China
| | - Qingdi Quentin Li
- Scientific Review Branch, Division of Extramural Research and Training, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, U.S.A
| | - Jinliang Duan
- 924 Hospital of PLA Joint Logistic Support Force, Guilin, P. R. China
| | - Xiaosheng Lu
- Department of Urology, People's Hospital of Beiliu, Beiliu, P. R. China;
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10
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Carlo G, Valentina M, Daniele C, Simone S, Edlira S, Giancarlo B, Benedetto GA. The environmental and occupational influence of pesticides on male fertility: a systematic review of human studies. Andrology 2022; 10:1250-1271. [PMID: 35793270 PMCID: PMC9541307 DOI: 10.1111/andr.13228] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 06/28/2022] [Accepted: 07/01/2022] [Indexed: 11/26/2022]
Abstract
BACKGROUND Environment plays a key role in male infertility, changing the incidence in various populations, and pesticides are one of the most studied hazards. The use of the latter has never decreased, jeopardizing the safety of workers and the general population. OBJECTIVE Our purpose was to summarize the results of studies discussing the association between pesticides and male fertility. METHODS A comprehensive literature search was performed through MEDLINE via PubMed, Scopus, and Web of Science. Only human studies were considered. Semen parameters, and DNA integrity were considered to evaluate the effect of pesticides on men. RESULTS A total of 64 studies that investigated their impact in terms of semen parameters (51 studies), chromatin and DNA integrity (25 studies), were included. The most frequently affected parameters were total sperm count sperm motility and morphology, although a reduction in ejaculate volume and concentration occur in several cases. A tangible worsening of semen quality was associated with organochlorines and organophosphates. Furthermore, pesticide exposure, especially pyrethroids, was related to a higher DNA fragmentation index and chromosome aneuploidy in most articles. CONCLUSION The epidemiological evidence supports the association between pesticides and male fertility for workers and the exposed population in terms of semen quality, DNA fragmentation and chromosome aneuploidy. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Giulioni Carlo
- "Polytechnic University of Marche Region", Department of Urology, Ancona, Italy
| | - Maurizi Valentina
- "Polytechnic University of Marche Region, Ospedali Riuniti" University Hospital, Department of Clinical and Molecular Sciences, Ancona, Italy
| | - Castellani Daniele
- "Ospedali Riuniti" University Hospital, Department of Urology, Ancona, Italy
| | - Scarcella Simone
- "Polytechnic University of Marche Region", Department of Urology, Ancona, Italy
| | - Skrami Edlira
- "Polytechnic University of Marche Region", Centre of Epidemiology and Biostatistics, Ancona, Italy
| | - Balercia Giancarlo
- "Ospedali Riuniti" University Hospital, Department of Endocrinology and Metabolic Diseases, Ancona, Italy
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Darbandi S, Darbandi M, Khorram Khorshid HR, Sengupta P. Electrophysiology of Human Gametes: A Systematic Review. World J Mens Health 2022; 40:442-455. [PMID: 35021309 PMCID: PMC9253800 DOI: 10.5534/wjmh.210107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 09/05/2021] [Accepted: 09/14/2021] [Indexed: 11/15/2022] Open
Abstract
PURPOSE Oocytes and spermatozoa are electrogenic cells with the ability to respond to electrical stimuli and modulate their electrical properties accordingly. Determination of the ionic events during the gamete maturation helps to design suitable culture media for gametes in assisted reproductive technology (ART). The present systematic review focuses on the electrophysiology of human gametes during different stages of maturation and also during fertilization. MATERIALS AND METHODS The reports published in the English language between January 2000 and July 2021 were extracted from various electronic scientific databases following the PRISMA checklist using specific MeSH keywords. RESULTS Subsequent to the screening process with defined inclusion and exclusion criteria, 60 articles have been included in this review. Among them, 11 articles were directly related to the electrophysiology of human oocytes and 49 physiology department to the electrophysiology of human spermatozoa. CONCLUSIONS Gametes generate electrical currents by ionic exchange, particularly Na+, K+, Cl-, H+, Zn2+, Cu2+, Se2+, Mg2+, HCO3-, and Ca2+ through specific ion channels in different stages of gamete maturation. The ionic concentrations, pH, and other physicochemical variables are modulated during the gametogenesis, maturation, activation, and the fertilization process following gamete function and metabolism. The electrical properties of human gametes change during different stages of maturation. Although it is demonstrated that the electrical properties are significant regulators of cell signaling and are fundamental to gamete maturation and fertilization, their exact roles in these processes are still poorly understood. Further research is required to unveil the intricate electrophysiological processes of human gamete maturation.
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Affiliation(s)
- Sara Darbandi
- Fetal Health Research Center, Hope Generation Foundation, Tehran, Iran
| | - Mahsa Darbandi
- Fetal Health Research Center, Hope Generation Foundation, Tehran, Iran
| | - Hamid Reza Khorram Khorshid
- Gene Therapy and Regenerative Medicine Research Center, Hope Generation Foundation, Tehran, Iran
- Personalized Medicine and Genometabolomics Research Center, Hope Generation Foundation, Tehran, Iran
| | - Pallav Sengupta
- Department of Physiology, Faculty of Medicine, Biosciences and Nursing, MAHSA University, Jenjarom, Selangor, Malaysia
- School of Medical Sciences, Bharath Institute of Higher Education and Research (BIHER), Chennai, India.
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12
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Zhou L, Yu Z, Xia Y, Cheng S, Gao J, Sun W, Jiang X, Zhang J, Mao L, Qin X, Zou Z, Qiu J, Chen C. Repression of autophagy leads to acrosome biogenesis disruption caused by a sub-chronic oral administration of polystyrene nanoparticles. ENVIRONMENT INTERNATIONAL 2022; 163:107220. [PMID: 35381522 DOI: 10.1016/j.envint.2022.107220] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 03/28/2022] [Accepted: 03/28/2022] [Indexed: 06/14/2023]
Abstract
As a new widespread contaminant, nanoplastics (NPs) pose a potential risk to human health. Nevertheless, the adverse effects of NPs on the male reproductive system are poorly understood. In this study, we aimed to determine the effects of polystyrene nanoplastics (PS-NPs) (50 nm) on sperm quality, with a focus on the acrosome defects. After 35 days of intragastric administration, sperm quality was decreased and testicular structures were impaired in mice exposed to PS-NPs in both the medium (1.0 mg/kg) and high dose (10 mg/kg) groups. No significant changes were observed in the low dose (0.2 mg/kg) group. Meanwhile, acrosome parameters including acrosome integrity and acrosome reaction were decreased after the administration of PS-NPs. These findings were consistent with the disruption of acrosome biogenesis, as identified by the changed testicular ultrastructure. Additionally, the findings were further validated using seven marker genes (Gba2, Pick1, Gopc, Hrb, Zpbp1, Spaca1 and Dpy19l2) essential for acrosome formation, which showed that two of these genes (Gopc and Dpy19l2) were significantly down-regulated. Moreover, repressed autophagy was observed in the testes of PS-NPs-exposed mice based on autophagy-related protein expression. This phenomenon was further verified in GC-2spd cells treated with PS-NPs (50 μg/mL, 100 μg/mL, 200 μg/mL for 24 h). The potential role of autophagy in such acrosome defects was explored by using the autophagy inhibitor 3-methyladenine (3-MA), autophagy activator rapamycin or beclin-1 siRNA. The results showed that Golgi-associated vesicle disorganization was exacerbated with the 3-MA and beclin-1 siRNA pretreatments, but decreased with the rapamycin pretreatment, and the expression of GOPC and DPY19L2 was also altered. These results indicated that autophagy might be involved in the PS-NPs-induced acrosome lesions based on the regulation of two key acrosome-formation proteins, GOPC and DPY19L2. Altogether, our results will provide new insights into the PS-NPs-induced male reproductive impairment.
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Affiliation(s)
- Lixiao Zhou
- Department of Health Laboratory Technology, School of Public Health and Management, Chongqing Medical University, Chongqing 400016, People's Republic of China
| | - Ziying Yu
- Department of Occupational and Environmental Health, School of Public Health and Management, Chongqing Medical University, Chongqing 400016, People's Republic of China
| | - Yinyin Xia
- Department of Occupational and Environmental Health, School of Public Health and Management, Chongqing Medical University, Chongqing 400016, People's Republic of China
| | - Shuqun Cheng
- Department of Occupational and Environmental Health, School of Public Health and Management, Chongqing Medical University, Chongqing 400016, People's Republic of China
| | - Jieying Gao
- Department of Health Laboratory Technology, School of Public Health and Management, Chongqing Medical University, Chongqing 400016, People's Republic of China
| | - Wei Sun
- Department of Occupational and Environmental Health, School of Public Health and Management, Chongqing Medical University, Chongqing 400016, People's Republic of China
| | - Xuejun Jiang
- Center of Experimental Teaching for Public Health, Experimental Teaching and Management Center, Chongqing Medical University, Chongqing 400016, People's Republic of China; Dongsheng Lung-Brain Disease Joint Lab, Chongqing Medical University, Chongqing 400016, People's Republic of China
| | - Jun Zhang
- Dongsheng Lung-Brain Disease Joint Lab, Chongqing Medical University, Chongqing 400016, People's Republic of China; Molecular Biology Laboratory of Respiratory Diseases, Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, People's Republic of China
| | - Lejiao Mao
- Dongsheng Lung-Brain Disease Joint Lab, Chongqing Medical University, Chongqing 400016, People's Republic of China; Molecular Biology Laboratory of Respiratory Diseases, Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, People's Republic of China
| | - Xia Qin
- Department of Pharmacy, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, People's Republic of China
| | - Zhen Zou
- Dongsheng Lung-Brain Disease Joint Lab, Chongqing Medical University, Chongqing 400016, People's Republic of China; Molecular Biology Laboratory of Respiratory Diseases, Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, People's Republic of China.
| | - Jingfu Qiu
- Department of Health Laboratory Technology, School of Public Health and Management, Chongqing Medical University, Chongqing 400016, People's Republic of China.
| | - Chengzhi Chen
- Department of Occupational and Environmental Health, School of Public Health and Management, Chongqing Medical University, Chongqing 400016, People's Republic of China; Dongsheng Lung-Brain Disease Joint Lab, Chongqing Medical University, Chongqing 400016, People's Republic of China.
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13
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Rato L, Sousa ACA. The Impact of Endocrine-Disrupting Chemicals in Male Fertility: Focus on the Action of Obesogens. J Xenobiot 2021; 11:163-196. [PMID: 34940512 PMCID: PMC8709303 DOI: 10.3390/jox11040012] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 11/12/2021] [Accepted: 11/23/2021] [Indexed: 12/11/2022] Open
Abstract
The current scenario of male infertility is not yet fully elucidated; however, there is increasing evidence that it is associated with the widespread exposure to endocrine-disrupting chemicals (EDCs), and in particular to obesogens. These compounds interfere with hormones involved in the regulation of metabolism and are associated with weight gain, being also able to change the functioning of the male reproductive axis and, consequently, the testicular physiology and metabolism that are pivotal for spermatogenesis. The disruption of these tightly regulated metabolic pathways leads to adverse reproductive outcomes. The permanent exposure to obesogens has raised serious health concerns. Evidence suggests that obesogens are one of the leading causes of the marked decline of male fertility and key players in shaping the future health outcomes not only for those who are directly exposed but also for upcoming generations. In addition to the changes that lead to inefficient functioning of the male gametes, obesogens induce alterations that are “imprinted” on the genes of the male gametes, establishing a link between generations and contributing to the transmission of defects. Unveiling the molecular mechanisms by which obesogens induce toxicity that may end-up in epigenetic modifications is imperative. This review describes and discusses the suggested molecular targets and potential mechanisms for obesogenic–disrupting chemicals and the subsequent effects on male reproductive health.
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Affiliation(s)
- Luís Rato
- Health School of the Polytechnic Institute of Guarda, 6300-035 Guarda, Portugal
- Correspondence: (L.R.); (A.C.A.S.)
| | - Ana C. A. Sousa
- Department of Biology, School of Science and Technology, University of Évora, 7006-554 Évora, Portugal
- Comprehensive Health Research Centre (CHRC), University of Évora, 7000-671 Évora, Portugal
- Correspondence: (L.R.); (A.C.A.S.)
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14
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Quilaqueo N, Villegas JV. Endocrine disruptor chemicals. A review of their effects on male reproduction and antioxidants as a strategy to counter it. Andrologia 2021; 54:e14302. [PMID: 34761829 DOI: 10.1111/and.14302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 09/28/2021] [Indexed: 12/18/2022] Open
Abstract
Endocrine disruptor chemicals are exogenous molecules that generate adverse effects on human health by destabilizing the homeostasis of endocrine system and affecting directly human reproductive system by inhibiting or activating oestrogenic or androgenic receptors. Endocrine disruptor chemicals generate transgenerational epigenetic problems, besides being associated with male infertility. Epidemiological data indicate that the increase in reproductive problems in males in the last 50 years is correlated with the increase of endocrine disrupting chemicals in the environment, being associated with a decrease in semen quality and direct effects on spermatozoa, such as alterations in motility, viability and acrosomal reaction, due to the generation of oxidative stress, and have also been postulated as a possible cause of testicular dysgenesis syndrome. Diverse antioxidants, such as C and E vitamins, N-acetylcysteine, selenium and natural vegetable extracts, are among the alternatives under study to counter the effects of endocrine disruptor chemicals. In some cases, the usage of them has given positive results and the opposite in others. In this review, we summarize the recent information about the effects of endocrine disruptor chemicals on male reproduction, on sperm cells, and the results of studies that have tested antioxidants as a strategy to diminish their harmful effects.
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Affiliation(s)
- Nelson Quilaqueo
- Center of Reproductive Biotechnology - Scientific and Technological Bioresource Nucleus (CEBIOR - BIOREN), University of La Frontera, Temuco, Chile
| | - Juana V Villegas
- Center of Reproductive Biotechnology - Scientific and Technological Bioresource Nucleus (CEBIOR - BIOREN), University of La Frontera, Temuco, Chile.,Department of Internal Medicine, Faculty of Medicine, University of La Frontera, Temuco, Chile
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15
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Ješeta M, Navrátilová J, Franzová K, Fialková S, Kempisty B, Ventruba P, Žáková J, Crha I. Overview of the Mechanisms of Action of Selected Bisphenols and Perfluoroalkyl Chemicals on the Male Reproductive Axes. Front Genet 2021; 12:692897. [PMID: 34646297 PMCID: PMC8502804 DOI: 10.3389/fgene.2021.692897] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 09/13/2021] [Indexed: 12/17/2022] Open
Abstract
Male fertility has been deteriorating worldwide for considerable time, with the greatest deterioration recorded mainly in the United States, Europe countries, and Australia. That is, especially in countries where an abundance of chemicals called endocrine disruptors has repeatedly been reported, both in the environment and in human matrices. Human exposure to persistent and non-persistent chemicals is ubiquitous and associated with endocrine-disrupting effects. This group of endocrine disrupting chemicals (EDC) can act as agonists or antagonists of hormone receptors and can thus significantly affect a number of physiological processes. It can even negatively affect human reproduction with an impact on the development of gonads and gametogenesis, fertilization, and the subsequent development of embryos. The negative effects of endocrine disruptors on sperm gametogenesis and male fertility in general have been investigated and repeatedly demonstrated in experimental and epidemiological studies. Male reproduction is affected by endocrine disruptors via their effect on testicular development, impact on estrogen and androgen receptors, potential epigenetic effect, production of reactive oxygen species or direct effect on spermatozoa and other cells of testicular tissue. Emerging scientific evidence suggests that the increasing incidence of male infertility is associated with the exposure to persistent and non-persistent endocrine-disrupting chemicals such as bisphenols and perfluoroalkyl chemicals (PFAS). These chemicals may impact men’s fertility through various mechanisms. This study provides an overview of the mechanisms of action common to persistent (PFAS) and nonpersistent (bisphenols) EDC on male fertility.
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Affiliation(s)
- Michal Ješeta
- Department of Obstetrics and Gynecology, Faculty of Medicine Masaryk University and University Hospital Brno, Brno, Czechia.,Department of Veterinary Sciences, Czech University of Life Sciences Prague, Prague, Czechia
| | - Jana Navrátilová
- RECETOX Centre, Faculty of Science, Masaryk University, Brno, Czechia
| | - Kateřina Franzová
- Department of Obstetrics and Gynecology, Faculty of Medicine Masaryk University and University Hospital Brno, Brno, Czechia
| | - Sandra Fialková
- RECETOX Centre, Faculty of Science, Masaryk University, Brno, Czechia
| | - Bartozs Kempisty
- Department of Histology and Embryology, Poznan University of Medical Sciences, Poznan, Poland.,Department of Anatomy, Poznan University of Medical Sciences, Poznan, Poland.,Department of Veterinary Medicine, Nicolaus Copernicus University, Torun, Poland.,Prestage Department of Poultry Science, College of Agriculture and Life Sciences, North Carolina State University, Raleigh, NC, United States
| | - Pavel Ventruba
- Department of Obstetrics and Gynecology, Faculty of Medicine Masaryk University and University Hospital Brno, Brno, Czechia
| | - Jana Žáková
- Department of Obstetrics and Gynecology, Faculty of Medicine Masaryk University and University Hospital Brno, Brno, Czechia
| | - Igor Crha
- Department of Obstetrics and Gynecology, Faculty of Medicine Masaryk University and University Hospital Brno, Brno, Czechia.,Department of Nursing and Midwifery, Faculty of Medicine, Masaryk University, Brno, Czechia
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16
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Rahban R, Rehfeld A, Schiffer C, Brenker C, Egeberg Palme DL, Wang T, Lorenz J, Almstrup K, Skakkebaek NE, Strünker T, Nef S. The antidepressant Sertraline inhibits CatSper Ca2+ channels in human sperm. Hum Reprod 2021; 36:2638-2648. [PMID: 34486673 PMCID: PMC8450872 DOI: 10.1093/humrep/deab190] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 06/01/2021] [Indexed: 12/12/2022] Open
Abstract
STUDY QUESTION Do selective serotonin reuptake inhibitor (SSRI) antidepressants affect the function of human sperm? SUMMARY ANSWER The SSRI antidepressant Sertraline (e.g. Zoloft) inhibits the sperm-specific Ca2+ channel CatSper and affects human sperm function in vitro. WHAT IS KNOWN ALREADY In human sperm, CatSper translates changes of the chemical microenvironment into changes of the intracellular Ca2+ concentration ([Ca2+]i) and swimming behavior. CatSper is promiscuously activated by oviductal ligands, but also by synthetic chemicals that might disturb the fertilization process. It is well known that SSRIs have off-target actions on Ca2+, Na+ and K+ channels in somatic cells. Whether SSRIs affect the activity of CatSper is, however, unknown. STUDY DESIGN, SIZE, DURATION We studied the action of the seven drugs belonging to the most commonly prescribed class of antidepressants, SSRIs, on resting [Ca2+]i and Ca2+ influx via CatSper in human sperm. The SSRI Sertraline was selected for in-depth analysis of its action on steroid-, prostaglandin-, pH- and voltage-activation of human CatSper. Moreover, the action of Sertraline on sperm acrosomal exocytosis and penetration into viscous media was evaluated. PARTICIPANTS/MATERIALS, SETTING, METHODS The activity of CatSper was investigated in sperm of healthy volunteers, using kinetic Ca2+ fluorimetry and patch-clamp recordings. Acrosomal exocytosis was investigated using Pisum sativum agglutinin and image cytometry. Sperm penetration in viscous media was evaluated using the Kremer test. MAIN RESULTS AND THE ROLE OF CHANCE Several SSRIs affected [Ca2+]i and attenuated ligand-induced Ca2+ influx via CatSper. In particular, the SSRI Sertraline almost completely suppressed Ca2+ influx via CatSper. Remarkably, the drug was about four-fold more potent to suppress prostaglandin- versus steroid-induced Ca2+ influx. Sertraline also suppressed alkaline- and voltage-activation of CatSper, indicating that the drug directly inhibits the channel. Finally, Sertraline impaired ligand-induced acrosome reaction and sperm penetration into viscous media. LIMITATIONS, REASONS FOR CAUTION This is an in vitro study. Future studies have to assess the physiological relevance in vivo. WIDER IMPLICATIONS OF THE FINDINGS The off-target action of Sertraline on CatSper in human sperm might impair the fertilization process. In a research setting, Sertraline may be used to selectively inhibit prostaglandin-induced Ca2+ influx. STUDY FUNDING/COMPETING INTEREST(S) This work was supported by the Swiss Centre for Applied Human Toxicology (SCAHT), the Département de l’Instruction Publique of the State of Geneva, the German Research Foundation (CRU326), the Interdisciplinary Center for Clinical Research, Münster (IZKF; Str/014/21), the Innovation Fund Denmark (grant numbers 14-2013-4) and the EDMaRC research grant from the Kirsten and Freddy Johansen’s Foundation. The authors declare that no conflict of interest could be perceived as prejudicing the impartiality of the research reported. TRIAL REGISTRATION NUMBER NA.
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Affiliation(s)
- Rita Rahban
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland.,Swiss Centre for Applied Human Toxicology, Basel, Switzerland
| | - Anders Rehfeld
- Department of Growth and Reproduction, University of Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Christian Schiffer
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany
| | - Christoph Brenker
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany
| | | | - Tao Wang
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany.,Institute of Life Science and School of Life Science, Nanchang University, Nanchang, Jiangxi, PR China
| | - Johannes Lorenz
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany
| | - Kristian Almstrup
- Department of Growth and Reproduction, University of Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Niels E Skakkebaek
- Department of Growth and Reproduction, University of Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Timo Strünker
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany
| | - Serge Nef
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland.,Swiss Centre for Applied Human Toxicology, Basel, Switzerland
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17
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Rehfeld A. Revisiting the action of steroids and triterpenoids on the human sperm Ca2+ channel CatSper. Mol Hum Reprod 2021; 26:816-824. [PMID: 32926144 DOI: 10.1093/molehr/gaaa062] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/15/2020] [Indexed: 02/07/2023] Open
Abstract
The sperm-specific Ca2+ channel CatSper (cation channel of sperm) is vital for male fertility. Contradictory findings have been published on the regulation of human CatSper by the endogenous steroids estradiol, testosterone and hydrocortisone, as well as the plant triterpenoids, lupeol and pristimerin. The aim of this study was to elucidate this controversy by investigating the action of these steroids and plant triterpenoids on human CatSper using population-based Ca2+-fluorimetric measurements, the specific CatSper-inhibitor RU1968 and a functional test assessing the CatSper-dependent penetration of human sperm cells into methylcellulose. Estradiol, testosterone and hydrocortisone were found to induce Ca2+-signals in human sperm cells with EC50 values in the lower μM range. By employing the specific CatSper-inhibitor RU1968, all three steroids were shown to induce Ca2+-signals through an action on CatSper, similar to progesterone. The steroids were found to dose-dependently inhibit subsequent progesterone-induced Ca2+-signals with IC50 values in the lower μM range. Additionally, the three steroids were found to significantly increase the penetration of human sperm cells into methylcellulose, similar to the effect of progesterone. The two plant triterpenoids, lupeol and pristimerin, were unable to inhibit progesterone-induced Ca2+-signals, whereas the CatSper-inhibitor RU1968 strongly inhibited progesterone-induced Ca2+-signals. In conclusion, this study supports the claim that the steroids estradiol, testosterone and hydrocortisone act agonistically on CatSper in human sperm cells, thereby mimicking the effect of progesterone, and that lupeol and pristimerin do not act as inhibitors of human CatSper.
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Affiliation(s)
- Anders Rehfeld
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
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18
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Gao J, Zhang H, Xiong P, Yan X, Liao C, Jiang G. Application of electrophysiological technique in toxicological study: From manual to automated patch-clamp recording. Trends Analyt Chem 2020. [DOI: 10.1016/j.trac.2020.116082] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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19
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Rahban R, Nef S. CatSper: The complex main gate of calcium entry in mammalian spermatozoa. Mol Cell Endocrinol 2020; 518:110951. [PMID: 32712386 DOI: 10.1016/j.mce.2020.110951] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 07/17/2020] [Accepted: 07/20/2020] [Indexed: 02/06/2023]
Abstract
Calcium ions (Ca2+) are involved in nearly every aspect of cellular life. They are one of the most abundant elements in mammals and play a vital role in physiological and biochemical processes acting mainly as intracellular messengers. In spermatozoa, several key functions are regulated by cytoplasmic Ca2+ concentration such as sperm capacitation, chemotaxis, hyperactive motility, and acrosome reaction. The sperm-specific ion channel CatSper is the principal calcium channel in sperm mediating the calcium influx into the sperm flagellum and acting as an essential modulator of downstream mechanisms involved in fertilization. This review aims to provide insights into the structure, localization, and function of the mammalian CatSper channel, primarily human and mice. The activation of CatSper by progesterone and prostaglandins, as well as the ligand-independent regulation of the channel by a change in the membrane voltage and intracellular pH are going to be addressed. Finally, major questions, challenges, and perspectives are discussed.
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Affiliation(s)
- Rita Rahban
- Swiss Centre for Applied Human Toxicology (SCAHT), Switzerland; Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, Rue Michel-Servet 1, 1206, Geneva, Switzerland.
| | - Serge Nef
- Swiss Centre for Applied Human Toxicology (SCAHT), Switzerland; Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, Rue Michel-Servet 1, 1206, Geneva, Switzerland.
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20
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Sperm ion channels and transporters in male fertility and infertility. Nat Rev Urol 2020; 18:46-66. [PMID: 33214707 DOI: 10.1038/s41585-020-00390-9] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/08/2020] [Indexed: 12/16/2022]
Abstract
Mammalian sperm cells must respond to cues originating from along the female reproductive tract and from the layers of the egg in order to complete their fertilization journey. Dynamic regulation of ion signalling is, therefore, essential for sperm cells to adapt to their constantly changing environment. Over the past 15 years, direct electrophysiological recordings together with genetically modified mouse models and human genetics have confirmed the importance of ion channels, including the principal Ca2+-selective plasma membrane ion channel CatSper, for sperm activity. Sperm ion channels and membrane receptors are attractive targets for both the development of contraceptives and infertility treatment drugs. Furthermore, in this era of assisted reproductive technologies, understanding the signalling processes implicated in defective sperm function, particularly those arising from genetic abnormalities, is of the utmost importance not only for the development of infertility treatments but also to assess the overall health of a patient and his children. Future studies to improve reproductive health care and overall health care as a function of the ability to reproduce should include identification and analyses of gene variants that underlie human infertility and research into fertility-related molecules.
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21
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Tamburrino L, Marchiani S, Muratori M, Luconi M, Baldi E. Progesterone, spermatozoa and reproduction: An updated review. Mol Cell Endocrinol 2020; 516:110952. [PMID: 32712385 DOI: 10.1016/j.mce.2020.110952] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 06/16/2020] [Accepted: 07/20/2020] [Indexed: 12/12/2022]
Abstract
The rapid effects of steroids on spermatozoa have been demonstrated for the first time more than three decades ago. Progesterone (P), which is present throughout the female genital tract with peaks of levels in the cumulus matrix surrounding the oocyte, has been shown to stimulate several sperm functions in vitro, including capacitation, hyperactivation, chemotaxis and acrosome reaction (AR). Besides an increase of intracellular calcium, P has been shown to activate other sperm signalling pathways including tyrosine phosphorylation of several sperm proteins. All these effects are mediated by extra-nuclear pathways likely involving interaction with molecules present on the sperm surface. In particular, the increase in intracellular calcium ([Ca2+]i) in spermatozoa from human and several other mammalian species is mediated by the sperm specific calcium channel CatSper, whose expression and function are required for sperm hyperactive motility. P-mediated CatSper activation is indeed involved in promoting sperm hyperactivation, but the involvement of this channel in other P-stimulated sperm functions, such as AR and chemotaxis, is less clear and further studies are required to disclose all the involved pathways. In human spermatozoa, responsiveness to P in terms of [Ca2+]i increase and AR is highly related to sperm fertilizing ability in vitro, suggesting that the steroid is a physiological inducer of AR during in vitro fertilization. In view of their physiological relevance, P-stimulated sperm functions are currently investigated to develop new tools to select highly performant spermatozoa for assisted reproduction.
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Affiliation(s)
- Lara Tamburrino
- Department of Experimental and Clinical Medicine, University of Florence, Viale Pieraccini 6, 50139, Florence, Italy
| | - Sara Marchiani
- Department of Experimental and Clinical Medicine, University of Florence, Viale Pieraccini 6, 50139, Florence, Italy
| | - Monica Muratori
- Department of Experimental and Clinical Biomedical Science, University of Florence, Viale Pieraccini 6, 50139, Florence, Italy
| | - Michaela Luconi
- Department of Experimental and Clinical Biomedical Science, University of Florence, Viale Pieraccini 6, 50139, Florence, Italy
| | - Elisabetta Baldi
- Department of Experimental and Clinical Medicine, University of Florence, Viale Pieraccini 6, 50139, Florence, Italy.
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22
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Wang T, Young S, Krenz H, Tüttelmann F, Röpke A, Krallmann C, Kliesch S, Zeng XH, Brenker C, Strünker T. The Ca 2+ channel CatSper is not activated by cAMP/PKA signaling but directly affected by chemicals used to probe the action of cAMP and PKA. J Biol Chem 2020; 295:13181-13193. [PMID: 32703901 DOI: 10.1074/jbc.ra120.013218] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 07/21/2020] [Indexed: 12/14/2022] Open
Abstract
The sperm-specific Ca2+ channel CatSper (cation channel of sperm) controls the influx of Ca2+ into the flagellum and, thereby, the swimming behavior of sperm. A hallmark of human CatSper is its polymodal activation by membrane voltage, intracellular pH, and oviductal hormones. Whether CatSper is also activated by signaling pathways involving an increase of cAMP and ensuing activation of PKA is, however, a matter of controversy. To shed light on this question, we used kinetic ion-sensitive fluorometry, patch-clamp recordings, and optochemistry to study transmembrane Ca2+ flux and membrane currents in human sperm from healthy donors and from patients that lack functional CatSper channels. We found that human CatSper is neither activated by intracellular cAMP directly nor indirectly by the cAMP/PKA-signaling pathway. Instead, we show that nonphysiological concentrations of cAMP and membrane-permeable cAMP analogs used to mimic the action of intracellular cAMP activate human CatSper from the outside via a hitherto-unknown extracellular binding site. Finally, we demonstrate that the effects of common PKA inhibitors on human CatSper rest predominantly, if not exclusively, on off-target drug actions on CatSper itself rather than on inhibition of PKA. We conclude that the concept of an intracellular cAMP/PKA-activation of CatSper is primarily based on unspecific effects of chemical probes used to interfere with cAMP signaling. Altogether, our findings solve several controversial issues and reveal a novel ligand-binding site controlling the activity of CatSper, which has important bearings on future studies of cAMP and Ca2+ signaling in sperm.
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Affiliation(s)
- Tao Wang
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, Jiangxi, China; Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany
| | - Samuel Young
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany
| | - Henrike Krenz
- Institute of Medical Informatics, University of Münster, Münster, Germany
| | - Frank Tüttelmann
- Institute of Human Genetics, University of Münster, Münster, Germany
| | - Albrecht Röpke
- Institute of Human Genetics, University of Münster, Münster, Germany
| | - Claudia Krallmann
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany
| | - Sabine Kliesch
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany
| | - Xu-Hui Zeng
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, Jiangxi, China.
| | - Christoph Brenker
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany.
| | - Timo Strünker
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Münster, Germany; Cells in Motion Interfaculty Centre, University of Münster, Münster, Germany.
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Sharma A, Mollier J, Brocklesby RWK, Caves C, Jayasena CN, Minhas S. Endocrine-disrupting chemicals and male reproductive health. Reprod Med Biol 2020; 19:243-253. [PMID: 32684823 PMCID: PMC7360961 DOI: 10.1002/rmb2.12326] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 03/04/2020] [Accepted: 03/23/2020] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND A number of different types of endocrine-disrupting chemicals (EDCs) including bisphenol A, phthalates, pesticides, and other environmental chemicals have been shown to adversely impact upon male reproductive health. Understanding the potential effects of EDCs on male reproductive health may enable the development of novel treatments and early prevention of the effects of EDCs on male infertility and their potential long-term sequelae. This review critically evaluates the research performed in this area and explores potential harmful effects of EDCs in animals and humans, including the possibility of trans-generational transmission. METHODS A literature review was conducted using electronic databases using the following terms: 'endocrine disrupt*' OR 'endocrine disruptors' OR 'endocrine disruptor chemicals' OR 'EDC' AND 'sperm*' OR 'spermatozoa' OR 'spermatozoon' OR 'male reproductive health' OR' male fertility'. MAIN FINDINGS Several studies have shown that EDCs have a variety of pathophysiological effects. These include failure of spermatogenesis, embryonic development, the association with testicular cancer, and long-term metabolic effects. CONCLUSIONS Several studies observe correlations between chemical doses and at least one sperm parameter; however, such correlations are sometimes inconsistent between different studies. Mechanisms through which EDCs exert their pathophysiological effects have not yet been fully elucidated in human studies.
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Affiliation(s)
- Aditi Sharma
- Section of Investigative MedicineFaculty of MedicineImperial College LondonLondonUK
| | - Josephine Mollier
- Section of Investigative MedicineFaculty of MedicineImperial College LondonLondonUK
| | | | - Charlotte Caves
- Section of Investigative MedicineFaculty of MedicineImperial College LondonLondonUK
| | - Channa N. Jayasena
- Section of Investigative MedicineFaculty of MedicineImperial College LondonLondonUK
- Imperial Centre for AndrologyImperial College Healthcare NHS TrustLondonUK
| | - Suks Minhas
- Imperial Centre for AndrologyImperial College Healthcare NHS TrustLondonUK
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24
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Warner GR, Mourikes VE, Neff AM, Brehm E, Flaws JA. Mechanisms of action of agrochemicals acting as endocrine disrupting chemicals. Mol Cell Endocrinol 2020; 502:110680. [PMID: 31838026 PMCID: PMC6942667 DOI: 10.1016/j.mce.2019.110680] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 12/06/2019] [Accepted: 12/10/2019] [Indexed: 02/07/2023]
Abstract
Agrochemicals represent a significant class of endocrine disrupting chemicals that humans and animals around the world are exposed to constantly. Agrochemicals can act as endocrine disrupting chemicals through a variety of mechanisms. Recent studies have shown that several mechanisms of action involve the ability of agrochemicals to mimic the interaction of endogenous hormones with nuclear receptors such as estrogen receptors, androgen receptors, peroxisome proliferator activated receptors, the aryl hydrocarbon receptor, and thyroid hormone receptors. Further, studies indicate that agrochemicals can exert toxicity through non-nuclear receptor-mediated mechanisms of action. Such non-genomic mechanisms of action include interference with peptide, steroid, or amino acid hormone response, synthesis and degradation as well as epigenetic changes (DNA methylation and histone modifications). This review summarizes the major mechanisms of action by which agrochemicals target the endocrine system.
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Affiliation(s)
- Genoa R Warner
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Urbana, 61802, IL, United States
| | - Vasiliki E Mourikes
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Urbana, 61802, IL, United States
| | - Alison M Neff
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Urbana, 61802, IL, United States
| | - Emily Brehm
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Urbana, 61802, IL, United States
| | - Jodi A Flaws
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Urbana, 61802, IL, United States.
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25
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Yuan Y, Ding X, Cheng Y, Kang H, Luo T, Zhang X, Kuang H, Chen Y, Zeng X, Zhang D. PFOA evokes extracellular Ca 2+ influx and compromises progesterone-induced response in human sperm. CHEMOSPHERE 2020; 241:125074. [PMID: 31627108 DOI: 10.1016/j.chemosphere.2019.125074] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 10/03/2019] [Accepted: 10/07/2019] [Indexed: 06/10/2023]
Abstract
Perfluorooctane acid (PFOA), a persistent organic pollutant, is ubiquitously present in the environment and may detrimentally affect male reproductive health. In this study, mature human sperm were in vitro exposed to different concentrations of PFOA (0.25, 2.5 or 25 μg/ml) alone or in combination with progesterone (P4) to evaluate the toxicity and the potential mechanism of action. Exposure to high-dose PFOA (25 μg/ml) alone for 4 h caused a decline in capacity of human spermatozoa to penetrate synthetic mucus, with an increased production of reactive oxygen species (ROS). Furthermore, PFOA treatment (2.5 and 25 μg/ml) evoked a transient rise in intracellular calcium concentration [Ca2+]i by activating the sperm-specific CatSper channel. However, preincubation with PFOA (2.5-25 μg/ml) for 4 h significantly suppressed P4-stimulated extracellular Ca2+ influx in human spermatozoa. Moreover, PFOA pretreatment at all concentrations evaluated markedly compromised P4-induced acrosome reaction and sperm penetration into viscous medium. Taken together, these results suggest that PFOA exposure may impair human sperm function through inducing oxidative stress and disturbing P4-induced Ca2+ signaling.
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Affiliation(s)
- Yangyang Yuan
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, 330031, PR China
| | - Xinbao Ding
- Department of Biomedical Sciences, Cornell University, Ithaca, NY, 14853, USA
| | - Yimin Cheng
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, 330031, PR China
| | - Hang Kang
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, 330031, PR China
| | - Tao Luo
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, 330031, PR China
| | - Xiaoning Zhang
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, 330031, PR China
| | - Haibin Kuang
- Department of Physiology, School of Basic Medical Sciences, Jiangxi Provincial Key Laboratory of Reproductive Physiology and Pathology, Nanchang University, Nanchang, 330006, PR China
| | - Ying Chen
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, 330031, PR China
| | - Xuhui Zeng
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, 330031, PR China.
| | - Dalei Zhang
- Department of Physiology, School of Basic Medical Sciences, Jiangxi Provincial Key Laboratory of Reproductive Physiology and Pathology, Nanchang University, Nanchang, 330006, PR China.
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26
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Trebichalská Z, Holubcová Z. Perfect date-the review of current research into molecular bases of mammalian fertilization. J Assist Reprod Genet 2020; 37:243-256. [PMID: 31909446 PMCID: PMC7056734 DOI: 10.1007/s10815-019-01679-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 12/22/2019] [Indexed: 12/21/2022] Open
Abstract
Fertilization is a multistep process during which two terminally differentiated haploid cells, an egg and a sperm, combine to produce a totipotent diploid zygote. In the early 1950s, it became possible to fertilize mammalian eggs in vitro and study the sequence of cellular and molecular events leading to embryo development. Despite all the achievements of assisted reproduction in the last four decades, remarkably little is known about the molecular aspects of human conception. Current fertility research in animal models is casting more light on the complexity of the process all our lives start with. This review article provides an update on the investigation of mammalian fertilization and highlights the practical implications of scientific discoveries in the context of human reproduction and reproductive medicine.
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Affiliation(s)
- Zuzana Trebichalská
- Faculty of Medicine, Department of Histology and Embryology, Masaryk University, Kamenice 5, Brno, Czech Republic
| | - Zuzana Holubcová
- Faculty of Medicine, Department of Histology and Embryology, Masaryk University, Kamenice 5, Brno, Czech Republic. .,Reprofit International, Clinic of Reproductive Medicine, Brno, Czech Republic.
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27
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Rehfeld A, Andersson AM, Skakkebæk NE. Bisphenol A Diglycidyl Ether (BADGE) and Bisphenol Analogs, but Not Bisphenol A (BPA), Activate the CatSper Ca 2+ Channel in Human Sperm. Front Endocrinol (Lausanne) 2020; 11:324. [PMID: 32508751 PMCID: PMC7248311 DOI: 10.3389/fendo.2020.00324] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 04/27/2020] [Indexed: 12/15/2022] Open
Abstract
Aim: Evidence suggests that bisphenol A diglycidyl ether (BADGE), bisphenol A (BPA), and BPA analogs can interfere with human male fertility. However, the effect directly on human sperm function is not known. The CatSper Ca2+ channel in human sperm controls important sperm functions and is necessary for normal male fertility. Environmental chemicals have been shown to activate CatSper and thereby affect Ca2+ signaling in human sperm. BPA has previously been investigated for effects on Ca2+ signaling human sperm, whereas the effects of other BPA analogs are currently unknown. The aim of this study is thus to characterize the effect of BADGE, BPA, and the eight analogs BPG, BPAF, BPC, BPB, BPBP, BPE, BPF, BPS on Ca2+ signaling, and CatSper in human sperm. Methods: Direct effects of the bisphenols on Ca2+ signaling in human sperm cells were evaluated using a Ca2+ fluorimetric assay measuring changes in intracellular Ca2+. Effects via CatSper were assessed using the specific CatSper inhibitor RU1968. Effects on human sperm function was assessed using an image cytometry-based acrosome reaction assay and the modified Kremer's sperm-mucus penetration assay. Results: At 10 μM the bisphenols BPG, BPAF, BPC, BADGE, BPB, and BPBP induced Ca2+ signals in human sperm cells, whereas BPE, BPF, BPS, and BPA had no effect. The efficacy of the chemicals at 10 μM is BPG > BPAF > BPC > BADGE > BPB > BPBP. Dose-response relations of BPG, BPAF, BPC, BADGE, BPB, and BPBP yielded EC50-values in the nM-μM range. The induced Ca2+ signals were almost completely abolished using the CatSper inhibitor RU1968, indicating an effect of the bisphenols on CatSper. All bisphenols, except BPBP, were found to dose-dependently inhibit progesterone-induced Ca2+ signals, with BPG and BPAF displaying inhibition even in low μM doses. BPG and BPAF were shown to affect human sperm function in a progesterone-like manner. Conclusion: Our results show that the bisphenols BPG, BPAF, BPC, BADGE, BPB, and BPBP can affect Ca2+ signaling in human sperm cells through activation of CatSper. This could potentially disrupt human sperm function by interfering with normal CatSper-signaling and thus be a contributing factor in human infertility, either alone or in mixtures with other chemicals.
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Affiliation(s)
- Anders Rehfeld
- Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
- *Correspondence: Anders Rehfeld
| | - A. M. Andersson
- Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - N. E. Skakkebæk
- Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
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28
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Brown SG, Publicover SJ, Barratt CLR, Martins da Silva SJ. Human sperm ion channel (dys)function: implications for fertilization. Hum Reprod Update 2019; 25:758-776. [PMID: 31665287 PMCID: PMC6847974 DOI: 10.1093/humupd/dmz032] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 07/14/2019] [Accepted: 08/13/2019] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Intensive research on sperm ion channels has identified members of several ion channel families in both mouse and human sperm. Gene knock-out studies have unequivocally demonstrated the importance of the calcium and potassium conductances in sperm for fertility. In both species, the calcium current is carried by the highly complex cation channel of sperm (CatSper). In mouse sperm, the potassium current has been conclusively shown to be carried by a channel consisting of the pore forming subunit SLO3 and auxiliary subunit leucine-rich repeat-containing 52 (LRRC52). However, in human sperm it is controversial whether the pore forming subunit of the channel is composed of SLO3 and/or SLO1. Deciphering the role of the proton-specific Hv1 channel is more challenging as it is only expressed in human sperm. However, definitive evidence for a role in, and importance for, human fertility can only be determined through studies using clinical samples. OBJECTIVE AND RATIONALE This review aims to provide insight into the role of sperm ion channels in human fertilization as evidenced from recent studies of sperm from infertile men. We also summarize the key discoveries from mouse ion channel knock-out models and contrast the properties of mouse and human CatSper and potassium currents. We detail the evidence for, and consequences of, defective ion channels in human sperm and discuss hypotheses to explain how defects arise and why affected sperm have impaired fertilization potential. SEARCH METHODS Relevant studies were identified using PubMed and were limited to ion channels that have been characterized in mouse and human sperm. Additional notable examples from other species are included as appropriate. OUTCOMES There are now well-documented fundamental differences between the properties of CatSper and potassium channel currents in mouse and human sperm. However, in both species, sperm lacking either channel cannot fertilize in vivo and CatSper-null sperm also fail to fertilize at IVF. Sperm-lacking potassium currents are capable of fertilizing at IVF, albeit at a much lower rate. However, additional complex and heterogeneous ion channel dysfunction has been reported in sperm from infertile men, the causes of which are unknown. Similarly, the nature of the functional impairment of affected patient sperm remains elusive. There are no reports of studies of Hv1 in human sperm from infertile men. WIDER IMPLICATIONS Recent studies using sperm from infertile men have given new insight and critical evidence supporting the supposition that calcium and potassium conductances are essential for human fertility. However, it should be highlighted that many fundamental questions remain regarding the nature of molecular and functional defects in sperm with dysfunctional ion channels. The development and application of advanced technologies remains a necessity to progress basic and clinical research in this area, with the aim of providing effective screening methodologies to identify and develop treatments for affected men in order to help prevent failed ART cycles. Conversely, development of drugs that block calcium and/or potassium conductances in sperm is a plausible strategy for producing sperm-specific contraceptives.
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Affiliation(s)
- Sean G Brown
- School of Applied Sciences, Abertay University, Dundee DD11HG, UK
| | | | - Christopher L R Barratt
- Systems Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD19SY, UK
| | - Sarah J Martins da Silva
- Systems Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD19SY, UK
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29
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Abstract
The identification of potential environmental hazards may be clinically relevant in the diagnosis of male infertility. Knowledge about these factors will improve prevention of fertility disorders. Apart from drugs or factors related to lifestyle such as alcohol and tobacco smoke, various environmental and occupational agents, both chemical and physical, may impair male reproductive function. Reproductive toxicity may evolve at the hypothalamic-pituitary, testicular, or post-testicular level; endpoints comprise deterioration of spermatogenesis and sperm function as well as endocrine disorders and sexual dysfunction. With regard to the complex regulation of the male reproductive system, the available information concerning single exogenous factors and their mechanisms of action in humans is limited. This is also due to the fact that extrapolation of results obtained from experimental animal or in vitro studies remains difficult. Nevertheless, the assessment of relevant exposure to reproductive toxicants should be carefully evaluated during diagnostic procedures of andrological patients.
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30
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Brenker C, Rehfeld A, Schiffer C, Kierzek M, Kaupp UB, Skakkebæk NE, Strünker T. Synergistic activation of CatSper Ca2+ channels in human sperm by oviductal ligands and endocrine disrupting chemicals. Hum Reprod 2019; 33:1915-1923. [PMID: 30189007 DOI: 10.1093/humrep/dey275] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Indexed: 12/19/2022] Open
Abstract
STUDY QUESTION Does the chemosensory activation of CatSper Ca2+ channels in human sperm give rise to additive, sub-additive or even synergistic actions among agonists? SUMMARY ANSWER We show that oviductal ligands and endocrine disrupting chemicals (EDCs) activate human CatSper highly synergistically. WHAT IS KNOWN ALREADY In human sperm, the sperm-specific CatSper channel controls the intracellular Ca2+ concentration and, thereby, several crucial stages toward fertilization. CatSper is activated by oviductal ligands and structurally diverse EDCs. The chemicals mimic the action of the physiological ligands, which might interfere with the precisely coordinated sequence of events underlying fertilization. STUDY DESIGN, SIZE, DURATION For both oviductal ligands and EDCs, we examined in quantitative terms whether stimulation of human sperm in vitro with mixtures results in additive, sub-additive or synergistic actions. PARTICIPANTS/MATERIALS, SETTING, METHODS We studied activation of CatSper in sperm of healthy volunteers, using kinetic Ca2+ fluorimetry and patch-clamp recordings. The combined action of progesterone and prostaglandins and of the EDCs benzylidene camphor sulfonic acid (BCSA) and α-Zearalenol was evaluated by curve-shift analysis, curvilinear isobolographic analysis and the combination-index method. MAIN RESULTS AND THE ROLE OF CHANCE Analysis of the action of progesterone/prostaglandin and BCSA/α-Zearalenol mixtures in human sperm by fluorimetry revealed that the oviductal ligands and EDCs both evoke Ca2+ influx via CatSper in a highly synergistic fashion. Patch-clamp recordings of CatSper currents in human sperm corroborated the synergistic ligand-activation of the channel. LIMITATIONS, REASONS FOR CAUTION This is an in vitro study. Future studies have to assess the physiological relevance in vivo. WIDER IMPLICATIONS OF THE FINDINGS These findings indicate that the fertilization process is orchestrated by multiple oviductal CatSper agonists that act in concert to control the behavior of sperm. Moreover, our results substantiate the concerns regarding the negative impact of EDCs on male reproductive health. So far, safety thresholds like the "No Observed Adverse Effect Level (NOAEL)" or "No Observed Effect Concentration (NOEC)" are set for individual EDCs. Our finding that EDCs act synergistically in human sperm challenges the validity of this procedure. STUDY FUNDING/COMPETING INTEREST(S) This work was supported by the German Research Foundation (SFB 645; CRU326), the Cells-in-Motion (CiM) Cluster of Excellence, Münster, (FF-2016-17), the 'Innovative Medical Research' of the University of Münster Medical School (BR121507), an EDMaRC research grant from the Kirsten and Freddy Johansen's Foundation, and the Innovation Fund Denmark (InnovationsFonden; 14-2013-4). The authors have no competing financial interests.
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Affiliation(s)
- C Brenker
- Center of Reproductive Medicine and Andrology, University Hospital Münster, Münster, Germany
| | - A Rehfeld
- Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.,Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.,International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - C Schiffer
- Center of Reproductive Medicine and Andrology, University Hospital Münster, Münster, Germany
| | - M Kierzek
- Center of Reproductive Medicine and Andrology, University Hospital Münster, Münster, Germany
| | - U B Kaupp
- Department of Molecular Sensory Systems, Center of Advanced European Studies and Research, Bonn, Germany
| | - N E Skakkebæk
- Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.,Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - T Strünker
- Center of Reproductive Medicine and Andrology, University Hospital Münster, Münster, Germany
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31
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Laleethambika N, Anila V, Manojkumar C, Muruganandam I, Giridharan B, Ravimanickam T, Balachandar V. Diabetes and Sperm DNA Damage: Efficacy of Antioxidants. ACTA ACUST UNITED AC 2018. [DOI: 10.1007/s42399-018-0012-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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32
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Puga Molina LC, Luque GM, Balestrini PA, Marín-Briggiler CI, Romarowski A, Buffone MG. Molecular Basis of Human Sperm Capacitation. Front Cell Dev Biol 2018; 6:72. [PMID: 30105226 PMCID: PMC6078053 DOI: 10.3389/fcell.2018.00072] [Citation(s) in RCA: 143] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 06/19/2018] [Indexed: 12/31/2022] Open
Abstract
In the early 1950s, Austin and Chang independently described the changes that are required for the sperm to fertilize oocytes in vivo. These changes were originally grouped under name of “capacitation” and were the first step in the development of in vitro fertilization (IVF) in humans. Following these initial and fundamental findings, a remarkable number of observations led to characterization of the molecular steps behind this process. The discovery of certain sperm-specific molecules and the possibility to record ion currents through patch-clamp approaches helped to integrate the initial biochemical observation with the activity of ion channels. This is of particular importance in the male gamete due to the fact that sperm are transcriptionally inactive. Therefore, sperm must control all these changes that occur during their transit through the male and female reproductive tracts by complex signaling cascades that include post-translational modifications. This review is focused on the principal molecular mechanisms that govern human sperm capacitation with particular emphasis on comparing all the reported pieces of evidence with the mouse model.
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Affiliation(s)
- Lis C Puga Molina
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
| | - Guillermina M Luque
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
| | - Paula A Balestrini
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
| | - Clara I Marín-Briggiler
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
| | - Ana Romarowski
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
| | - Mariano G Buffone
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
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33
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Buck Louis GM, Smarr MM, Sun L, Chen Z, Honda M, Wang W, Karthikraj R, Weck J, Kannan K. Endocrine disrupting chemicals in seminal plasma and couple fecundity. ENVIRONMENTAL RESEARCH 2018; 163:64-70. [PMID: 29426029 PMCID: PMC5878734 DOI: 10.1016/j.envres.2018.01.028] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 01/20/2018] [Accepted: 01/22/2018] [Indexed: 05/02/2023]
Abstract
Growing evidence supports the importance of men's exposure to non-persistent endocrine disruptors (EDCs) and couple fecundability, as measured by time-to-pregnancy (TTP). This evolving literature contrasts with the largely equivocal findings reported for women's exposures and fecundity. While most evidence relies upon urinary concentrations, quantification of EDCs in seminal plasma may be more informative about potential toxicity arising within the testes. We analyzed 5 chemical classes of non-persistent EDCs in seminal plasma for 339 male partners of couples who were recruited prior to conception and who were followed daily until pregnant or after one year of trying. Benzophenones, bisphenols, parabens, and phthalate metabolites and phthalate diesters were measured using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) except for phthalate diesters, which were analyzed using gas chromatography-mass spectrometry. Cox regression with discrete-time was used to estimate fecundability odds ratios (FORs) and 95% confidence intervals (CIs) for each chemical to estimate the probability of pregnancy. While most EDCs were detected in seminal plasma, concentrations were lower than urinary concentrations previously analyzed for the cohort. None of the EDCs were significantly associated with fecundability even after covariate adjustment, though benzophenones consistently yielded FORs <1.0 (ranging from 0.72 to 0.91) in couple-adjusted models suggestive of diminished fecundity (longer TTP). The findings underscore that a range of EDCs can be quantified in seminal plasma, but the lower concentrations may require a large cohort for assessing couple fecundability, as well as the need to consider other fecundity outcomes such as semen quality.
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Affiliation(s)
- Germaine M Buck Louis
- Office of the Director, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute for Child Health and Human Development, The National Institutes of Health, 6710b Rockledge Drive, Bethesda, MD 20892, United States.
| | - Melissa M Smarr
- Office of the Director, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute for Child Health and Human Development, The National Institutes of Health, 6710b Rockledge Drive, Bethesda, MD 20892, United States.
| | - Liping Sun
- Glotec, Inc., Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute for Child Health and Human Development, The National Institutes of Health, 6710b Rockledge Drive, Bethesda, MD 20892, United States.
| | - Zhen Chen
- Biostatistics and Bioinformatics Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute for Child Health and Human Development, The National Institutes of Health, 6710b Rockledge Drive, Bethesda, MD 20892, United States.
| | - Masato Honda
- Wadsworth Center, New York State Department of Health, Department of Environmental Health Sciences, School of Public Health, State University of New York at Albany, Albany, New York 12201, United States
| | - Wei Wang
- Wadsworth Center, New York State Department of Health, Department of Environmental Health Sciences, School of Public Health, State University of New York at Albany, Albany, New York 12201, United States
| | - Rajendiran Karthikraj
- Wadsworth Center, New York State Department of Health, Department of Environmental Health Sciences, School of Public Health, State University of New York at Albany, Albany, New York 12201, United States
| | - Jennifer Weck
- Office of the Director, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute for Child Health and Human Development, The National Institutes of Health, 6710b Rockledge Drive, Bethesda, MD 20892, United States.
| | - Kurunthachalam Kannan
- Wadsworth Center, New York State Department of Health, Department of Environmental Health Sciences, School of Public Health, State University of New York at Albany, Albany, New York 12201, United States.
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Rehfeld A, Egeberg DL, Almstrup K, Petersen JH, Dissing S, Skakkebæk NE. EDC IMPACT: Chemical UV filters can affect human sperm function in a progesterone-like manner. Endocr Connect 2018; 7:16-25. [PMID: 28874401 PMCID: PMC5744631 DOI: 10.1530/ec-17-0156] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 09/05/2017] [Indexed: 12/20/2022]
Abstract
Human sperm cell function must be precisely regulated to achieve natural fertilization. Progesterone released by the cumulus cells surrounding the egg induces a Ca2+ influx into human sperm cells via the CatSper Ca2+-channel and thereby controls sperm function. Multiple chemical UV filters have been shown to induce a Ca2+ influx through CatSper, thus mimicking the effect of progesterone on Ca2+ signaling. We hypothesized that these UV filters could also mimic the effect of progesterone on sperm function. We examined 29 UV filters allowed in sunscreens in the US and/or EU for their ability to affect acrosome reaction, penetration, hyperactivation and viability in human sperm cells. We found that, similar to progesterone, the UV filters 4-MBC, 3-BC, Meradimate, Octisalate, BCSA, HMS and OD-PABA induced acrosome reaction and 3-BC increased sperm penetration into a viscous medium. The capacity of the UV filters to induce acrosome reaction and increase sperm penetration was positively associated with the ability of the UV filters to induce a Ca2+ influx. None of the UV filters induced significant changes in the proportion of hyperactivated cells. In conclusion, chemical UV filters that mimic the effect of progesterone on Ca2+ signaling in human sperm cells can similarly mimic the effect of progesterone on acrosome reaction and sperm penetration. Human exposure to these chemical UV filters may impair fertility by interfering with sperm function, e.g. through induction of premature acrosome reaction. Further studies are needed to confirm the results in vivo.
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Affiliation(s)
- A Rehfeld
- Department of Growth and ReproductionCopenhagen University Hospital, Rigshospitalet, Denmark
- Department of Cellular and Molecular MedicineFaculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
- International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC)University of Copenhagen, Rigshospitalet, Denmark
| | - D L Egeberg
- Department of Growth and ReproductionCopenhagen University Hospital, Rigshospitalet, Denmark
- International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC)University of Copenhagen, Rigshospitalet, Denmark
| | - K Almstrup
- Department of Growth and ReproductionCopenhagen University Hospital, Rigshospitalet, Denmark
- International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC)University of Copenhagen, Rigshospitalet, Denmark
| | - J H Petersen
- Department of Growth and ReproductionCopenhagen University Hospital, Rigshospitalet, Denmark
- International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC)University of Copenhagen, Rigshospitalet, Denmark
- Department of BiostatisticsUniversity of Copenhagen, Copenhagen, Denmark
| | - S Dissing
- Department of Cellular and Molecular MedicineFaculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - N E Skakkebæk
- Department of Growth and ReproductionCopenhagen University Hospital, Rigshospitalet, Denmark
- International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC)University of Copenhagen, Rigshospitalet, Denmark
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Sun XH, Zhu YY, Wang L, Liu HL, Ling Y, Li ZL, Sun LB. The Catsper channel and its roles in male fertility: a systematic review. Reprod Biol Endocrinol 2017; 15:65. [PMID: 28810916 PMCID: PMC5558725 DOI: 10.1186/s12958-017-0281-2] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Accepted: 08/03/2017] [Indexed: 12/22/2022] Open
Abstract
The Catsper channel is a sperm-specific, Ca2+-permeable, pH-dependent, and low voltage-dependent channel that is essential for the hyperactivity of sperm flagellum, chemotaxis towards the egg, capacitation and acrosome reaction. All of these physiological events require calcium entry into sperm cells. Remarkably, Catsper genes are exclusively expressed in the testis during spermatogenesis, and are sensitive to ion channel-induced pH change, such as NHEs, Ca2+ATPase, K+ channel, Hv1 channel and HCO3- transporters. Furthermore, the Catsper channel is regulated by some physiological stimulants, such as progesterone, cyclic nucleotides (e.g., cAMP, cGMP), zona pellucida (ZP) glycoproteins and bovine serum albumin (BSA). All of these factors normally stimulate Ca2+ entry into sperm through the Catsper channel. In addition, the Catsper channel may be a potential target for male infertility treatment or contraception. This review will focus on the structure, functions, regulation mechanisms and medicinal targets of the Catsper channel.
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Affiliation(s)
- Xiang-hong Sun
- grid.412521.1Department of pharmacy, the affiliated hospital of Qingdao University Medical College, Qingdao, 266555 China
| | - Ying-ying Zhu
- 0000 0001 0455 0905grid.410645.2Department of pharmacy, College of pharmacy of Qingdao University, Qingdao, China
| | - Lin Wang
- grid.412521.1Department of clinical laboratory, the affiliated hospital of Qingdao University Medical College, Qingdao, China
| | - Hong-ling Liu
- grid.412521.1Department of pharmacy, the affiliated hospital of Qingdao University Medical College, Qingdao, 266555 China
| | - Yong Ling
- grid.412521.1Department of pharmacy, the affiliated hospital of Qingdao University Medical College, Qingdao, 266555 China
| | - Zong-li Li
- grid.412521.1Department of pharmacy, the affiliated hospital of Qingdao University Medical College, Qingdao, 266555 China
| | - Li-bo Sun
- grid.412521.1Department of pharmacy, the affiliated hospital of Qingdao University Medical College, Qingdao, 266555 China
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Tavares RS, Martins S, Almeida-Santos T, Sousa AP, Ramalho-Santos J, da Cruz E Silva OA. Alzheimer's disease-related amyloid-β 1-42 peptide induces the loss of human sperm function. Cell Tissue Res 2017; 369:647-651. [PMID: 28776187 DOI: 10.1007/s00441-017-2665-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 06/23/2017] [Indexed: 11/25/2022]
Abstract
Characteristically identified as the main component of senile plaques present in patients suffering from Alzheimer's disease, Aβ has been detected in human testis and reproductive fluids, but its effect on spermatozoa has not been addressed. The present study evaluated whether the most toxic and aggregant amyloid precursor protein (APP)-proteolytic product, amyloid-β1-42 (Aβ1-42), was capable of affecting sperm functionality. Normozoospermic samples were either exposed to different Aβ1-42 doses or to the untreated and scrambled controls for a maximum of 48 h at 37 °C and 5%CO2, and motility, viability and mitochondrial status were evaluated. Additionally, tyrosine phosphorylation was analyzed by immunocytochemistry and acrosomal integrity through PSA-FITC. A shorter treatment period was used to monitor prompt Ca2+ responses. Aβ1-42 peptide decreased motility before inducing mitochondrial impairment (p < 0.05; n = 6). Both outcomes became more pronounced with time, reaching their maximal decrease at 48 h, where even 1 μM produced undesirable effects (p < 0.05; n = 6). Aβ1-42 peptide also decreased cell survival (p < 0.05; n = 6). Furthermore, although no effects on tyrosine phosphorylation were observed (p > 0.05; n = 6), reduced acrosomal integrity was detected (p < 0.05; n = 7), which was not correlated with viability loss (p > 0.05). In parallel, all Aβ1-42 concentrations elicited a [Ca2+]i rise but a significant difference was only observed at 20 μM (p < 0.05; n = 7) and a tendency was obtained with 10 μM (p = 0.053; n = 7). In conclusion, Aβ1-42 peptide oligomers impair sperm function in vitro, although further studies are required to determine the clinical relevance of these findings.
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Affiliation(s)
- R S Tavares
- Neuroscience and Cell Signalling Group, Department of Medical Sciences, Institute of Biomedicine - iBiMED, University of Aveiro, 3810-193, Aveiro, Portugal.,Biology of Reproduction and Stem Cell Group, CNC- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504, Coimbra, Portugal
| | - S Martins
- Neuroscience and Cell Signalling Group, Department of Medical Sciences, Institute of Biomedicine - iBiMED, University of Aveiro, 3810-193, Aveiro, Portugal
| | - T Almeida-Santos
- Biology of Reproduction and Stem Cell Group, CNC- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504, Coimbra, Portugal.,Reproductive Medicine Service, University Hospitals of Coimbra, 3000-075, Coimbra, Portugal.,Faculty of Medicine, University of Coimbra, 3000-548, Coimbra, Portugal
| | - A P Sousa
- Biology of Reproduction and Stem Cell Group, CNC- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504, Coimbra, Portugal.,Reproductive Medicine Service, University Hospitals of Coimbra, 3000-075, Coimbra, Portugal
| | - J Ramalho-Santos
- Biology of Reproduction and Stem Cell Group, CNC- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504, Coimbra, Portugal. .,Department of Life Sciences, Faculty of Sciences and Technology, University of Coimbra, Calçada Martins de Freitas, 3000-456, Coimbra, Portugal.
| | - O A da Cruz E Silva
- Neuroscience and Cell Signalling Group, Department of Medical Sciences, Institute of Biomedicine - iBiMED, University of Aveiro, 3810-193, Aveiro, Portugal.,Department of Medical Sciences, University of Aveiro, 3810-193, Aveiro, Portugal
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Abstract
Fertilization is exceptionally complex and, depending on the species, happens in entirely different environments. External fertilizers in aquatic habitats, like marine invertebrates or fish, release their gametes into the seawater or freshwater, whereas sperm from most internal fertilizers like mammals cross the female genital tract to make their way to the egg. Various chemical and physical cues guide sperm to the egg. Quite generally, these cues enable signaling pathways that ultimately evoke a cellular Ca2+ response that modulates the waveform of the flagellar beat and, hence, the swimming path. To cope with the panoply of challenges to reach and fertilize the egg, sperm from different species have developed their own unique repertoire of signaling molecules and mechanisms. Here, we review the differences and commonalities for sperm sensory signaling in marine invertebrates (sea urchin), fish (zebrafish), and mammals (mouse, human).
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Affiliation(s)
- Dagmar Wachten
- Minerva Max Planck Research Group, Molecular Physiology, Center of Advanced European Studies and Research (caesar), 53175 Bonn, Germany
| | - Jan F Jikeli
- Minerva Max Planck Research Group, Molecular Physiology, Center of Advanced European Studies and Research (caesar), 53175 Bonn, Germany
| | - U Benjamin Kaupp
- Department Molecular Sensory Systems, Center of Advanced European Studies and Research (caesar), 53175 Bonn, Germany
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38
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Martins da Silva SJ, Brown SG, Sutton K, King LV, Ruso H, Gray DW, Wyatt PG, Kelly MC, Barratt CL, Hope AG. Drug discovery for male subfertility using high-throughput screening: a new approach to an unsolved problem. Hum Reprod 2017; 32:974-984. [PMID: 28333338 PMCID: PMC5850465 DOI: 10.1093/humrep/dex055] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 12/16/2016] [Accepted: 03/02/2017] [Indexed: 12/15/2022] Open
Abstract
STUDY QUESTION Can pharma drug discovery approaches be utilized to transform investigation into novel therapeutics for male infertility? SUMMARY ANSWER High-throughput screening (HTS) is a viable approach to much-needed drug discovery for male factor infertility. WHAT IS KNOWN ALREADY There is both huge demand and a genuine clinical need for new treatment options for infertile men. However, the time, effort and resources required for drug discovery are currently exorbitant, due to the unique challenges of the cellular, physical and functional properties of human spermatozoa and a lack of appropriate assay platform. STUDY DESIGN, SIZE, DURATION Spermatozoa were obtained from healthy volunteer research donors and subfertile patients undergoing IVF/ICSI at a hospital-assisted reproductive techniques clinic between January 2012 and November 2016. PARTICIPANTS/MATERIALS, SETTING, METHODS A HTS assay was developed and validated using intracellular calcium ([Ca2+]i) as a surrogate for motility in human spermatozoa. Calcium fluorescence was detected using a Flexstation microplate reader (384-well platform) and compared with responses evoked by progesterone, a compound known to modify a number of biologically relevant behaviours in human spermatozoa. Hit compounds identified following single point drug screen (10 μM) of an ion channel-focussed library assembled by the University of Dundee Drug Discovery Unit were rescreened to ensure potency using standard 10 point half-logarithm concentration curves, and tested for purity and integrity using liquid chromatography and mass spectrometry. Hit compounds were grouped by structure activity relationships and five representative compounds then further investigated for direct effects on spermatozoa, using computer-assisted sperm assessment, sperm penetration assay and whole-cell patch clamping. MAIN RESULTS AND THE ROLE OF CHANCE Of the 3242 ion channel library ligands screened, 384 compounds (11.8%) elicited a statistically significant increase in calcium fluorescence, with greater than 3× median absolute deviation above the baseline. Seventy-four compounds eliciting ≥50% increase in fluorescence in the primary screen were rescreened and evaluated further, resulting in 48 hit compounds that produced a concentration-dependent increase in [Ca2+]i. Sperm penetration studies confirmed in vitro exposure to two hit compounds (A and B) resulted in significant improvement in functional motility in spermatozoa from healthy volunteer donors (A: 1 cm penetration index 2.54, 2 cm penetration index 2.49; P < 0.005 and B: 1 cm penetration index 2.1, 2 cm penetration index 2.6; P < 0.005), but crucially, also in patient samples from those undergoing fertility treatment (A: 1 cm penetration index 2.4; P = 0.009, 2 cm penetration index 3.6; P = 0.02 and B: 1 cm penetration index 2.2; P = 0.0004, 2 cm penetration index 3.6; P = 0.002). This was primarily as a result of direct or indirect CatSper channel action, supported by evidence from electrophysiology studies of individual sperm. LIMITATIONS, REASONS FOR CAUTION Increase and fluxes in [Ca2+]i are fundamental to the regulation of sperm motility and function, including acrosome reaction. The use of calcium signalling as a surrogate for sperm motility is acknowledged as a potential limitation in this study. WIDER IMPLICATIONS OF THE FINDINGS We conclude that HTS can robustly, efficiently, identify novel compounds that increase [Ca2+]i in human spermatozoa and functionally modify motility, and propose its use as a cornerstone to build and transform much-needed drug discovery for male infertility. STUDY FUNDING/COMPETING INTEREST(S) The majority of the data were obtained using funding from TENOVUS Scotland and Chief Scientist Office NRS Fellowship. Additional funding was provided by NHS Tayside, MRC project grants (MR/K013343/1, MR/012492/1) and University of Abertay. The authors declare that there is no conflict of interest. TRAIL REGISTRATION NUMBER N/A.
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Affiliation(s)
- Sarah J. Martins da Silva
- Reproductive and Developmental Biology, University of Dundee, Ninewells Hospital, Dundee DD1 9SY, UK
- Assisted Conception Unit, Ninewells Hospital, Dundee DD1 9SY, UK
| | - Sean G. Brown
- School of Science Engineering and Technology, University of Abertay, Dundee DD1 1HG, UK
| | - Keith Sutton
- Reproductive and Developmental Biology, University of Dundee, Ninewells Hospital, Dundee DD1 9SY, UK
| | - Louise V. King
- Reproductive and Developmental Biology, University of Dundee, Ninewells Hospital, Dundee DD1 9SY, UK
| | - Halil Ruso
- Reproductive and Developmental Biology, University of Dundee, Ninewells Hospital, Dundee DD1 9SY, UK
| | - David W. Gray
- Drug Discovery Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Paul G. Wyatt
- Drug Discovery Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Mark C. Kelly
- Reproductive and Developmental Biology, University of Dundee, Ninewells Hospital, Dundee DD1 9SY, UK
| | - Christopher L.R. Barratt
- Reproductive and Developmental Biology, University of Dundee, Ninewells Hospital, Dundee DD1 9SY, UK
- Assisted Conception Unit, Ninewells Hospital, Dundee DD1 9SY, UK
| | - Anthony G. Hope
- Drug Discovery Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
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39
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Cytotoxic and Genotoxic Effects of Acephate on Human Sperm. J Toxicol 2017; 2017:3874817. [PMID: 28392800 PMCID: PMC5368408 DOI: 10.1155/2017/3874817] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 02/09/2017] [Accepted: 02/20/2017] [Indexed: 11/18/2022] Open
Abstract
Extensive use of organophosphorus pesticides (OPs) could alter semen quality and sperm DNA at different stages of spermatogenesis. Acephate is a highly toxic extensively used OP and, therefore, we aimed to evaluate the effects of acephate on human semen quality and sperm DNA integrity. Sperm collected from healthy males were exposed to 0, 50, 100, and 200 μg/mL of acephate and incubated for 1 h, 2 h, and 3 h. Subsequently, sperm motility, vitality, functional integrity of plasma membrane, sperm capacitation, and DNA damage were examined. Result showed a significant decline of the motility at 100 μg/mL after 3 h and with 200 μg/mL after 1 h, 2 h, and 3 h. Viability was significantly reduced at 200 μg/mL after 2 h and 3 h. Functional integrity was significantly affected at 100 μg/mL after 3h and in 200 μg/mL dose after 2 h and 3h. Similarly, sperm capacitation was significantly affected at 200 μg/mL after 1 h, 2 h, and 3 h and at 100 μg/mL at 3 h. DNA damage was significantly increased only in 200 μg/mL dose after 3 h. The study suggests that exposure to acephate may result in alterations of sperm structure and function thus contributing towards deteriorating in human semen quality triggering infertility.
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40
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Zou QX, Peng Z, Zhao Q, Chen HY, Cheng YM, Liu Q, He YQ, Weng SQ, Wang HF, Wang T, Zheng LP, Luo T. Diethylstilbestrol activates CatSper and disturbs progesterone actions in human spermatozoa. Hum Reprod 2016; 32:290-298. [PMID: 28031325 DOI: 10.1093/humrep/dew332] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 11/24/2016] [Accepted: 12/16/2016] [Indexed: 12/28/2022] Open
Abstract
STUDY QUESTION Is diethylstilbestrol (DES), a prototypical endocrine-disrupting chemical (EDC), able to induce physiological changes in human spermatozoa and affect progesterone actions? SUMMARY ANSWER DES promoted Ca2+ flux into human spermatozoa by activating the cation channel of sperm (CatSper) and suppressed progesterone-induced Ca2+ signaling, tyrosine phosphorylation and sperm functions. WHAT IS KNOWN ALREADY DES significantly impairs the male reproductive system both in fetal and postnatal exposure. Although various EDCs affect human spermatozoa in a non-genomic manner, the effect of DES on human spermatozoa remains unknown. STUDY DESIGN, SIZE, DURATION Sperm samples from normozoospermic donors were exposed in vitro to a range of DES concentrations with or without progesterone at 37°C in a 5% CO2 incubator to mimic the putative exposure to this toxicant in seminal plasma and the female reproductive tract fluids. The incubation time varied according to the experimental protocols. All experiments were repeated at least five times using different individual sperm samples. PARTICIPANTS/MATERIALS, SETTING, METHODS Human sperm intracellular calcium concentrations ([Ca2+]i) were monitored with a multimode plate reader following sperm loading with Ca2+ indicator Fluo-4 AM, and the whole-cell patch-clamp technique was performed to record CatSper and alkalinization-activated sperm K+ channel (KSper) currents. Sperm viability and motility parameters were assessed by an eosin-nigrosin staining kit and a computer-assisted semen analysis system, respectively. The ability of sperm to penetrate into viscous media was examined by penetration into 1% methylcellulose. The sperm acrosome reaction was measured using chlortetracycline staining. The level of tyrosine phosphorylation was determined by western blot assay. MAIN RESULTS AND THE ROLE OF CHANCE DES exposure rapidly increased human sperm [Ca2+]i dose dependently and even at an environmentally relevant concentration (100 pM). The elevation of [Ca2+]i was derived from extracellular Ca2+ influx and mainly mediated by CatSper. Although DES did not affect sperm viability, motility, penetration into viscous media, tyrosine phosphorylation or the acrosome reaction, it suppressed progesterone-stimulated Ca2+ signaling and tyrosine phosphorylation. Consequently, DES (1-100 μM) significantly inhibited progesterone-induced human sperm penetration into viscous media and acrosome reaction. LARGE SCALE DATA N/A. LIMITATIONS, REASONS FOR CAUTION Although DES has been shown to disturb progesterone actions on human spermatozoa, this study was performed in vitro, and caution must be taken when extrapolating the results in practical applications. WIDER IMPLICATIONS OF THE FINDINGS The present study revealed that DES interfered with progesterone-stimulated Ca2+ signaling and tyrosine phosphorylation, ultimately inhibited progesterone-induced human sperm functions and, thereby, might impair sperm fertility. The non-genomic manner in which DES disturbs progesterone actions may be a potential mechanism for some estrogenic endocrine disruptors to affect human sperm function. STUDY FUNDING/COMPETING INTERESTS National Natural Science Foundation of China (No. 31400996); Natural Science Foundation of Jiangxi, China (No. 20161BAB204167 and No. 20142BAB215050); open project of National Population and Family Planning Key Laboratory of Contraceptives and Devices Research (No. 2016KF07) to T. Luo; National Natural Science Foundation of China (No. 81300539) to L.P. Zheng. The authors have no conflicts of interest to declare.
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Affiliation(s)
- Qian-Xing Zou
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, Jiangxi 330031, PR China
| | - Zhen Peng
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, Jiangxi 330031, PR China
| | - Qing Zhao
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, Jiangxi 330031, PR China
| | - Hou-Yang Chen
- Reproductive Medical Center, Jiangxi Provincial Maternal and Child Health Hospital, Nanchang, Jiangxi 330006, PR China
| | - Yi-Min Cheng
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, Jiangxi 330031, PR China
| | - Qing Liu
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, Jiangxi 330031, PR China
| | - Yuan-Qiao He
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, Jiangxi 330031, PR China
| | - Shi-Qi Weng
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, Jiangxi 330031, PR China
| | - Hua-Feng Wang
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, Jiangxi 330031, PR China
| | - Tao Wang
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, Jiangxi 330031, PR China
| | - Li-Ping Zheng
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, Jiangxi 330031, PR China
| | - Tao Luo
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang, Jiangxi 330031, PR China
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Kaupp UB, Strünker T. Signaling in Sperm: More Different than Similar. Trends Cell Biol 2016; 27:101-109. [PMID: 27825709 DOI: 10.1016/j.tcb.2016.10.002] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 10/13/2016] [Accepted: 10/14/2016] [Indexed: 11/30/2022]
Abstract
For a given sensory cell type, signaling motifs are rather uniform across phyla. By contrast, sperm from different species use diverse repertoires of sperm-specific signaling molecules and even closely related protein isoforms feature different properties and serve different functions. This surprising diversity has consequences for strategies in fertilization research and it will take some time to get the big picture. We discuss the function of receptors, ion channels, and exchangers embedded in cellular pathways from different sperm species.
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Affiliation(s)
- U B Kaupp
- Center of Advanced European Studies and Research (CAESAR), Department of Molecular Sensory Systems, Ludwig-Erhard-Allee 2, 53175 Bonn, Germany.
| | - T Strünker
- University Hospital Münster, Center of Reproductive Medicine and Andrology, Albert-Schweitzer-Campus 1, Geb. D11, 48149 Münster, Germany
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Rehfeld A, Dissing S, Skakkebæk NE. Chemical UV Filters Mimic the Effect of Progesterone on Ca 2+ Signaling in Human Sperm Cells. Endocrinology 2016; 157:4297-4308. [PMID: 27583790 DOI: 10.1210/en.2016-1473] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Progesterone released by cumulus cells surrounding the egg induces a Ca2+ influx into human sperm cells via the cationic channel of sperm (CatSper) Ca2+ channel and controls multiple Ca2+-dependent responses essential for fertilization. We hypothesized that chemical UV filters may mimic the physiological action of progesterone on CatSper, thus affecting Ca2+ signaling in human sperm cells. We examined 29 UV filters allowed in sunscreens in the United States and/or the European Union for their ability to induce Ca2+ signals in human sperm by applying measurements of the intracellular free Ca2+ concentration. We found that 13 UV filters induced a significant Ca2+ signal at 10 μM. Nine UV filters induced Ca2+ signals primarily by activating the CatSper channel. The UV filters 3-benzylidene camphor (3-BC) and benzylidene camphor sulfonic acid competitively inhibited progesterone-induced Ca2+ signals. Dose-response relations for the UV filters showed that the Ca2+ signal-inducing effects began in the nanomolar-micromolar range. Single-cell Ca2+ measurements showed a Ca2+ signal-inducing effect of the most potent UV filter, 3-BC, at 10 nM. Finally, we demonstrated that the 13 UV filters acted additively in low-dose mixtures to induce Ca2+ signals. In conclusion, 13 of 29 examined UV filters (44%) induced Ca2+ signals in human sperm. Nine UV filters primarily activated CatSper and thereby mimicked the effect of progesterone. The UV filters 3-BC and benzylidene camphor sulfonic acid competitively inhibited progesterone-induced Ca2+ signals. In vivo exposure studies are needed to investigate whether UV filter exposure affects human fertility.
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Affiliation(s)
- A Rehfeld
- Department of Growth and Reproduction (A.R., N.E.S.), Copenhagen University Hospital, Rigshospitalet, Department of Cellular and Molecular Medicine (A.R., S.D.), Faculty of Health Sciences, University of Copenhagen, and International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (A.R., N.E.S.), Rigshospitalet, University of Copenhagen, DK-2100, Copenhagen, Denmark
| | - S Dissing
- Department of Growth and Reproduction (A.R., N.E.S.), Copenhagen University Hospital, Rigshospitalet, Department of Cellular and Molecular Medicine (A.R., S.D.), Faculty of Health Sciences, University of Copenhagen, and International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (A.R., N.E.S.), Rigshospitalet, University of Copenhagen, DK-2100, Copenhagen, Denmark
| | - N E Skakkebæk
- Department of Growth and Reproduction (A.R., N.E.S.), Copenhagen University Hospital, Rigshospitalet, Department of Cellular and Molecular Medicine (A.R., S.D.), Faculty of Health Sciences, University of Copenhagen, and International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (A.R., N.E.S.), Rigshospitalet, University of Copenhagen, DK-2100, Copenhagen, Denmark
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43
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Exposure to p, p'-DDE Induces Morphological Changes and Activation of the PKC α-p38-C/EBP β Pathway in Human Promyelocytic HL-60 Cells. BIOMED RESEARCH INTERNATIONAL 2016; 2016:1375606. [PMID: 27833915 PMCID: PMC5090076 DOI: 10.1155/2016/1375606] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 08/26/2016] [Accepted: 08/31/2016] [Indexed: 01/23/2023]
Abstract
Dichlorodiphenyldichloroethylene (p,p′-DDE), the most persistent metabolite of dichlorodiphenyltrichloroethane (DDT), is still present in the human population. Both are present in the bone marrow of patients with bone marrow disorders, but thus far there are no studies that assess the capability of p,p′-DDE to affect myeloid cells. The aim of this study was to determine the effect of p,p′-DDE on promyelocytic cell differentiation and intracellular pathways related to this event. p,p′-DDE induced morphological changes compatible with promyelocytic differentiation in a concentration-dependent manner. The p,p′-DDE effect on [Ca2+]i, C/EBPβ protein levels, PKCα and p38 activation, and the role of oxidative stress or PLA2 was assayed. Exposure to 1.9 μg/mL of p,p′-DDE increased [Ca2+]i, PKCα, p38, and C/EBPβ protein levels; the increase of nuclear C/EBPβ protein was dependent on p38. PKCα phosphorylation was dependent on PLA2 and p,p′-DDE-induced oxidative stress. p38 phosphorylation induced by p,p′-DDE was dependent on PLA2, PKC activation, and oxidative stress. These effects of p,p′-DDE at concentrations found in human bone marrow may induce alterations in immature myeloid cells and could affect their cellular homeostasis. In order to establish the risk from exposure to p,p′-DDE on the development of bone marrow disorders in humans, these effects deserve further study.
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Shannon M, Rehfeld A, Frizzell C, Livingstone C, McGonagle C, Skakkebaek NE, Wielogórska E, Connolly L. In vitro bioassay investigations of the endocrine disrupting potential of steviol glycosides and their metabolite steviol, components of the natural sweetener Stevia. Mol Cell Endocrinol 2016; 427:65-72. [PMID: 26965840 DOI: 10.1016/j.mce.2016.03.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 02/11/2016] [Accepted: 03/04/2016] [Indexed: 01/02/2023]
Abstract
The food industry is moving towards the use of natural sweeteners such as those produced by Stevia rebaudiana due to the number of health and safety concerns surrounding artificial sweeteners. Despite the fact that these sweeteners are natural; they cannot be assumed safe. Steviol glycosides have a steroidal structure and therefore may have the potential to act as an endocrine disruptor in the body. Reporter gene assays (RGAs), H295R steroidogenesis assay and Ca(2+) fluorimetry based assays using human sperm cells have been used to assess the endocrine disrupting potential of two steviol glycosides: stevioside and rebaudioside A, and their metabolite steviol. A decrease in transcriptional activity of the progestagen receptor was seen following treatment with 25,000 ng/ml steviol in the presence of progesterone (157 ng/ml) resulting in a 31% decrease in progestagen response (p=<0.01). At the level of steroidogenesis, the metabolite steviol (500-25,000 ng/ml) increased progesterone production significantly by 2.3 fold when exposed to 10,000 ng/ml (p=<0.05) and 5 fold when exposed to 25,000 ng/ml (p=<0.001). Additionally, steviol was found to induce an agonistic response on CatSper, a progesterone receptor of sperm, causing a rapid influx of Ca(2+). The response was fully inhibited using a specific CatSper inhibitor. These findings highlight the potential for steviol to act as a potential endocrine disruptor.
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Affiliation(s)
- Maeve Shannon
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Northern Ireland, United Kingdom
| | - Anders Rehfeld
- Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Denmark; Department of Cellular and Molecular Medicine, Faculty of Health Sciences, Center for Healthy Ageing, University of Copenhagen, Copenhagen, Denmark; International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Rigshospitalet, University of Copenhagen, Denmark
| | - Caroline Frizzell
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Northern Ireland, United Kingdom
| | - Christina Livingstone
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Northern Ireland, United Kingdom
| | - Caoimhe McGonagle
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Northern Ireland, United Kingdom
| | - Niels E Skakkebaek
- Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Denmark; International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Rigshospitalet, University of Copenhagen, Denmark
| | - Ewa Wielogórska
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Northern Ireland, United Kingdom
| | - Lisa Connolly
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Northern Ireland, United Kingdom.
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Quan C, Shi Y, Wang C, Wang C, Yang K. p,p'-DDE damages spermatogenesis via phospholipid hydroperoxide glutathione peroxidase depletion and mitochondria apoptosis pathway. ENVIRONMENTAL TOXICOLOGY 2016; 31:593-600. [PMID: 25410718 DOI: 10.1002/tox.22072] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 10/21/2014] [Accepted: 10/31/2014] [Indexed: 06/04/2023]
Abstract
One, 1-dichloro-2,2-bis(p-chlorophenyl) ethylene (p,p'-DDE), the major metabolite of 2,2-bis(4-chlorophenyl)-1,1,1-trichloroethane (DDT), is a known persistent organic pollutant (POPs) and male reproductive toxicant. However, the mechanism by which p,p'-DDE exposure causes male reproductive toxicity remains unknown. The objective of this study was to elucidate some mechanisms involved in this process, including the mitochondria apoptosis pathway and the role of phospholipid hydroperoxide glutathione peroxidase (PHGPx). Puberty male SD rats were given different doses of p,p'-DDE (0, 20, 60, 100 mg/kg body weight), after the treatment, the semen quality was evaluated. Western blotting was used to detect the PHGPx protein expression. Furthermore, real-time PCR was used to analyze the genetic expression of PHGPx, Bax, Cytochrom C (Cyt C), Apaf-1, and caspase-3 in the testis. Results indicated that after the exposure, sperm malformation rate showed a significant rise compared with the control group, and meanwhile, the sperm density and sperm motility parameters were reduced to some extent in different treated groups. The mitochondria apoptosis pathway was activated. And remarkably, the expression of PHGPx protein was greatly reduced by the exposure. We conclude that p,p'-DDE can damage spermatogenesis via PHGPx depletion and mitochondria apoptosis pathway.
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Affiliation(s)
- Chao Quan
- Department of Occupational and Environmental Health, MOE Key Lab of Environment and Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yuqin Shi
- Department of Occupational and Environmental Health, MOE Key Lab of Environment and Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Department of epidemiology and health statistics, School of Public Health, Medical College, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Can Wang
- Department of Occupational and Environmental Health, MOE Key Lab of Environment and Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
- Hanyang Center for Disease Control and Prevention, Wuhan, Hubei, China
| | - Chengmin Wang
- Department of Occupational and Environmental Health, MOE Key Lab of Environment and Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Kedi Yang
- Department of Occupational and Environmental Health, MOE Key Lab of Environment and Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
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Cd(2+) sensitivity and permeability of a low voltage-activated Ca(2+) channel with CatSper-like selectivity filter. Cell Calcium 2016; 60:41-50. [PMID: 27134080 DOI: 10.1016/j.ceca.2016.03.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 03/21/2016] [Accepted: 03/30/2016] [Indexed: 11/22/2022]
Abstract
CatSper is a sperm-specific Ca(2+) channel that plays an essential role in the male fertility. However, its biophysical properties have been poorly characterized mainly due to its deficient heterologous expression. As other voltage-gated Ca(2+) channels (CaVs), CatSper possesses a conserved Ca(2+)-selective filter motif ([T/S]x[D/E]xW) in the pore region. Interestingly, CatSper conserves four aspartic acids (DDDD) as the negatively charged residues in this motif while high voltage-activated CaVs have four glutamic acids (EEEE) and low voltage-activated CaVs possess two glutamic acids and two aspartic acids (EEDD). Previous studies based on site-directed mutagenesis of L- and T-type channels showed that the number of D seems to have a negative correlation with their cadmium (Cd(2+)) sensitivity. These results suggest that CatSper (DDDD) would have low sensitivity to Cd(2+). To explore Cd(2+)-sensitivity and -permeability of CatSper, we performed two types of experiments: 1) Electrophysiological analysis of heterologously expressed human CaV3.1 channel and three pore mutants (DEDD, EDDD and DDDD), 2) Cd(2+) imaging of human spermatozoa with FluoZin-1. Electrophysiological studies showed a significant increase in Cd(2+) and manganese (Mn(2+)) currents through the CaV3.1 mutants as well as a reduction in the inhibitory effect of Cd(2+) on the Ca(2+) current. In fluorescence imaging with human sperm, we observed an increase in Cd(2+) influx potentiated by progesterone, a potent activator of CatSper. These results support our hypothesis, namely that Cd(2+)-sensitivity and -permeability are related to the absolute number of D in the Ca(2+)-selective filter independently to the type of the Cav channels.
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Skakkebaek NE, Rajpert-De Meyts E, Buck Louis GM, Toppari J, Andersson AM, Eisenberg ML, Jensen TK, Jørgensen N, Swan SH, Sapra KJ, Ziebe S, Priskorn L, Juul A. Male Reproductive Disorders and Fertility Trends: Influences of Environment and Genetic Susceptibility. Physiol Rev 2016; 96:55-97. [PMID: 26582516 DOI: 10.1152/physrev.00017.2015] [Citation(s) in RCA: 598] [Impact Index Per Article: 74.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
It is predicted that Japan and European Union will soon experience appreciable decreases in their populations due to persistently low total fertility rates (TFR) below replacement level (2.1 child per woman). In the United States, where TFR has also declined, there are ethnic differences. Caucasians have rates below replacement, while TFRs among African-Americans and Hispanics are higher. We review possible links between TFR and trends in a range of male reproductive problems, including testicular cancer, disorders of sex development, cryptorchidism, hypospadias, low testosterone levels, poor semen quality, childlessness, changed sex ratio, and increasing demand for assisted reproductive techniques. We present evidence that several adult male reproductive problems arise in utero and are signs of testicular dysgenesis syndrome (TDS). Although TDS might result from genetic mutations, recent evidence suggests that it most often is related to environmental exposures of the fetal testis. However, environmental factors can also affect the adult endocrine system. Based on our review of genetic and environmental factors, we conclude that environmental exposures arising from modern lifestyle, rather than genetics, are the most important factors in the observed trends. These environmental factors might act either directly or via epigenetic mechanisms. In the latter case, the effects of exposures might have an impact for several generations post-exposure. In conclusion, there is an urgent need to prioritize research in reproductive physiology and pathophysiology, particularly in highly industrialized countries facing decreasing populations. We highlight a number of topics that need attention by researchers in human physiology, pathophysiology, environmental health sciences, and demography.
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Affiliation(s)
- Niels E Skakkebaek
- Department of Growth & Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland; Department of Physiology & Pediatrics, University of Turku and Turku University Hospital, Turku, Finland; Male Reproductive Medicine & Surgery Program, Stanford University, Stanford, California; Icahn School of Medicine at Mount Sinai, New York, New York; and The Fertility Clinic, Rigshospitalet, Copenhagen, Denmark
| | - Ewa Rajpert-De Meyts
- Department of Growth & Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland; Department of Physiology & Pediatrics, University of Turku and Turku University Hospital, Turku, Finland; Male Reproductive Medicine & Surgery Program, Stanford University, Stanford, California; Icahn School of Medicine at Mount Sinai, New York, New York; and The Fertility Clinic, Rigshospitalet, Copenhagen, Denmark
| | - Germaine M Buck Louis
- Department of Growth & Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland; Department of Physiology & Pediatrics, University of Turku and Turku University Hospital, Turku, Finland; Male Reproductive Medicine & Surgery Program, Stanford University, Stanford, California; Icahn School of Medicine at Mount Sinai, New York, New York; and The Fertility Clinic, Rigshospitalet, Copenhagen, Denmark
| | - Jorma Toppari
- Department of Growth & Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland; Department of Physiology & Pediatrics, University of Turku and Turku University Hospital, Turku, Finland; Male Reproductive Medicine & Surgery Program, Stanford University, Stanford, California; Icahn School of Medicine at Mount Sinai, New York, New York; and The Fertility Clinic, Rigshospitalet, Copenhagen, Denmark
| | - Anna-Maria Andersson
- Department of Growth & Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland; Department of Physiology & Pediatrics, University of Turku and Turku University Hospital, Turku, Finland; Male Reproductive Medicine & Surgery Program, Stanford University, Stanford, California; Icahn School of Medicine at Mount Sinai, New York, New York; and The Fertility Clinic, Rigshospitalet, Copenhagen, Denmark
| | - Michael L Eisenberg
- Department of Growth & Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland; Department of Physiology & Pediatrics, University of Turku and Turku University Hospital, Turku, Finland; Male Reproductive Medicine & Surgery Program, Stanford University, Stanford, California; Icahn School of Medicine at Mount Sinai, New York, New York; and The Fertility Clinic, Rigshospitalet, Copenhagen, Denmark
| | - Tina Kold Jensen
- Department of Growth & Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland; Department of Physiology & Pediatrics, University of Turku and Turku University Hospital, Turku, Finland; Male Reproductive Medicine & Surgery Program, Stanford University, Stanford, California; Icahn School of Medicine at Mount Sinai, New York, New York; and The Fertility Clinic, Rigshospitalet, Copenhagen, Denmark
| | - Niels Jørgensen
- Department of Growth & Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland; Department of Physiology & Pediatrics, University of Turku and Turku University Hospital, Turku, Finland; Male Reproductive Medicine & Surgery Program, Stanford University, Stanford, California; Icahn School of Medicine at Mount Sinai, New York, New York; and The Fertility Clinic, Rigshospitalet, Copenhagen, Denmark
| | - Shanna H Swan
- Department of Growth & Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland; Department of Physiology & Pediatrics, University of Turku and Turku University Hospital, Turku, Finland; Male Reproductive Medicine & Surgery Program, Stanford University, Stanford, California; Icahn School of Medicine at Mount Sinai, New York, New York; and The Fertility Clinic, Rigshospitalet, Copenhagen, Denmark
| | - Katherine J Sapra
- Department of Growth & Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland; Department of Physiology & Pediatrics, University of Turku and Turku University Hospital, Turku, Finland; Male Reproductive Medicine & Surgery Program, Stanford University, Stanford, California; Icahn School of Medicine at Mount Sinai, New York, New York; and The Fertility Clinic, Rigshospitalet, Copenhagen, Denmark
| | - Søren Ziebe
- Department of Growth & Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland; Department of Physiology & Pediatrics, University of Turku and Turku University Hospital, Turku, Finland; Male Reproductive Medicine & Surgery Program, Stanford University, Stanford, California; Icahn School of Medicine at Mount Sinai, New York, New York; and The Fertility Clinic, Rigshospitalet, Copenhagen, Denmark
| | - Lærke Priskorn
- Department of Growth & Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland; Department of Physiology & Pediatrics, University of Turku and Turku University Hospital, Turku, Finland; Male Reproductive Medicine & Surgery Program, Stanford University, Stanford, California; Icahn School of Medicine at Mount Sinai, New York, New York; and The Fertility Clinic, Rigshospitalet, Copenhagen, Denmark
| | - Anders Juul
- Department of Growth & Reproduction and EDMaRC, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland; Department of Physiology & Pediatrics, University of Turku and Turku University Hospital, Turku, Finland; Male Reproductive Medicine & Surgery Program, Stanford University, Stanford, California; Icahn School of Medicine at Mount Sinai, New York, New York; and The Fertility Clinic, Rigshospitalet, Copenhagen, Denmark
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Tavares RS, Escada-Rebelo S, Correia M, Mota PC, Ramalho-Santos J. The non-genomic effects of endocrine-disrupting chemicals on mammalian sperm. Reproduction 2016; 151:R1-R13. [DOI: 10.1530/rep-15-0355] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Exposure to toxicants present in the environment, especially the so-called endocrine-disrupting chemicals (EDCs), has been associated with decreased sperm quality and increased anomalies in male reproductive organs over the past decades. Both human and animal populations are continuously exposed to ubiquitous synthetic and natural-occurring EDCs through diet, dermal contact and/or inhalation, therefore potentially compromising male reproductive health. Although the effects of EDC are likely induced via multiple genomic-based pathways, their non-genomic effects may also be relevant. Furthermore, spermatozoa are transcriptionally inactive cells that can come in direct contact with EDCs in reproductive fluids and secretions and are therefore a good model to address non-genomic effects. This review thus focuses on the non-genomic effects of several important EDCs relevant to mammalian exposure. Notably, EDCs were found to interfere with pre-existing pathways inducing a panoply of deleterious effects to sperm function that included altered intracellular Ca2+oscillations, induction of oxidative stress, mitochondrial dysfunction, increased DNA damage and decreased sperm motility and viability, among others, potentially jeopardizing male fertility. Although many studies have used non-environmentally relevant concentrations of only one compound for mechanistic studies, it is important to remember that mammals are not exposed to one, but rather to a multitude of environmental EDCs, and synergistic effects may occur. Furthermore, some effects have been detected with single compounds at environmentally relevant concentrations.
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Reinhardt K, Dobler R, Abbott J. An Ecology of Sperm: Sperm Diversification by Natural Selection. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2015. [DOI: 10.1146/annurev-ecolsys-120213-091611] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Using basic ecological concepts, we introduce sperm ecology as a framework to study sperm cells. First, we describe environmental effects on sperm and conclude that evolutionary and ecological research should not neglect the overwhelming evidence presented here (both in external and internal fertilizers and in terrestrial and aquatic habitats) that sperm function is altered by many environments, including the male environment. Second, we determine that the evidence for sperm phenotypic plasticity is overwhelming. Third, we find that genotype-by-environment interaction effects on sperm function exist, but their general adaptive significance (e.g., local adaptation) awaits further research. It remains unresolved whether sperm diversification occurs by natural selection acting on sperm function or by selection on male and female microenvironments that enable optimal plastic performance of sperm (sperm niches). Environmental effects reduce fitness predictability under sperm competition, predict species distributions under global change, explain adaptive behavior, and highlight the role of natural selection in behavioral ecology and reproductive medicine.
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Affiliation(s)
- Klaus Reinhardt
- Applied Zoology, Department of Biology, Technische Universität Dresden, 01062 Dresden, Germany;,
| | - Ralph Dobler
- Applied Zoology, Department of Biology, Technische Universität Dresden, 01062 Dresden, Germany;,
| | - Jessica Abbott
- Department of Biology, Lund University, 223 62 Lund, Sweden
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Miller MR, Mansell SA, Meyers SA, Lishko PV. Flagellar ion channels of sperm: similarities and differences between species. Cell Calcium 2015; 58:105-13. [DOI: 10.1016/j.ceca.2014.10.009] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 10/16/2014] [Accepted: 10/20/2014] [Indexed: 10/24/2022]
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