1
|
Balestrini PA, Sulzyk V, Jabloñski M, Schiavi-Ehrenhaus LJ, González SN, Ferreira JJ, Gómez-Elías MD, Pomata P, Luque GM, Krapf D, Cuasnicu PS, Santi CM, Buffone MG. Membrane potential hyperpolarization: a critical factor in acrosomal exocytosis and fertilization in sperm within the female reproductive tract. Front Cell Dev Biol 2024; 12:1386980. [PMID: 38803392 PMCID: PMC11128623 DOI: 10.3389/fcell.2024.1386980] [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: 02/16/2024] [Accepted: 04/24/2024] [Indexed: 05/29/2024] Open
Abstract
Hyperpolarization of the membrane potential (Em), a phenomenon regulated by SLO3 channels, stands as a central feature in sperm capacitation-a crucial process conferring upon sperm the ability to fertilize the oocyte. In vitro studies demonstrated that Em hyperpolarization plays a pivotal role in facilitating the mechanisms necessary for the development of hyperactivated motility (HA) and acrosomal exocytosis (AE) occurrence. Nevertheless, the physiological significance of sperm Em within the female reproductive tract remains unexplored. As an approach to this question, we studied sperm migration and AE incidence within the oviduct in the absence of Em hyperpolarization using a novel mouse model established by crossbreeding of SLO3 knock-out (KO) mice with EGFP/DsRed2 mice. Sperm from this model displays impaired HA and AE in vitro. Interestingly, examination of the female reproductive tract shows that SLO3 KO sperm can reach the ampulla, mirroring the quantity of sperm observed in wild-type (WT) counterparts, supporting that the HA needed to reach the fertilization site is not affected. However, a noteworthy distinction emerges-unlike WT sperm, the majority of SLO3 KO sperm arrive at the ampulla with their acrosomes still intact. Of the few SLO3 KO sperm that do manage to reach the oocytes within this location, fertilization does not occur, as indicated by the absence of sperm pronuclei in the MII-oocytes recovered post-mating. In vitro, SLO3 KO sperm fail to penetrate the ZP and fuse with the oocytes. Collectively, these results underscore the vital role of Em hyperpolarization in AE and fertilization within their physiological context, while also revealing that Em is not a prerequisite for the development of the HA motility, essential for sperm migration through the female tract to the ampulla.
Collapse
Affiliation(s)
- Paula A. Balestrini
- Instituto de Biología y Medicina Experimental (IByME)-Consejo Nacional de Investigaciones Científicas y Tícnicas, Buenos Aires, Argentina
| | - Valeria Sulzyk
- Instituto de Biología y Medicina Experimental (IByME)-Consejo Nacional de Investigaciones Científicas y Tícnicas, Buenos Aires, Argentina
| | - Martina Jabloñski
- Instituto de Biología y Medicina Experimental (IByME)-Consejo Nacional de Investigaciones Científicas y Tícnicas, Buenos Aires, Argentina
| | - Liza J. Schiavi-Ehrenhaus
- Instituto de Biología y Medicina Experimental (IByME)-Consejo Nacional de Investigaciones Científicas y Tícnicas, Buenos Aires, Argentina
| | - Soledad N. González
- Instituto de Biología y Medicina Experimental (IByME)-Consejo Nacional de Investigaciones Científicas y Tícnicas, Buenos Aires, Argentina
| | - Juan J. Ferreira
- Department of OB/GYN, Washington University School of Medicine, Saint Louis, MO, United States
| | - Matías D. Gómez-Elías
- Instituto de Biología y Medicina Experimental (IByME)-Consejo Nacional de Investigaciones Científicas y Tícnicas, Buenos Aires, Argentina
| | - Pablo Pomata
- Instituto de Biología y Medicina Experimental (IByME)-Consejo Nacional de Investigaciones Científicas y Tícnicas, Buenos Aires, Argentina
| | - Guillermina M. Luque
- Instituto de Biología y Medicina Experimental (IByME)-Consejo Nacional de Investigaciones Científicas y Tícnicas, Buenos Aires, Argentina
| | - Dario Krapf
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas–Universidad Nacional de Rosario, Rosario, Santa Fe, Argentina
| | - Patricia S. Cuasnicu
- Instituto de Biología y Medicina Experimental (IByME)-Consejo Nacional de Investigaciones Científicas y Tícnicas, Buenos Aires, Argentina
| | - Celia M. Santi
- Department of OB/GYN, Washington University School of Medicine, Saint Louis, MO, United States
| | - Mariano G. Buffone
- Instituto de Biología y Medicina Experimental (IByME)-Consejo Nacional de Investigaciones Científicas y Tícnicas, Buenos Aires, Argentina
| |
Collapse
|
2
|
Zhang J, Zheng L, Chen Y, Luo T, Zeng X, Kang H. LRRC52 is likely a functional component of human KSper†. Biol Reprod 2024; 110:711-721. [PMID: 38267364 DOI: 10.1093/biolre/ioae004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 07/19/2023] [Accepted: 01/05/2024] [Indexed: 01/26/2024] Open
Abstract
Completion of fertilization is orchestrated by various ion channels in sperm membrane. Hyperpolarization of membrane potential, an indispensable event during the capacitation process, is dominated by sperm potassium channel (KSper). In addition to sperm-specific SLO3, which forms the channel pore, the auxiliary subunit leucine-rich-repeat-containing protein 52 (LRRC52) is required to form mKSper to function under physiological conditions. However, in human sperm, although most evidence supports that hSLO3 is the pore-forming subunit, whether hLRRC52 contributes to hKSper conductance and modulates sperm function remains to be understood. Here, using an extracellular segment that is homologous between mice and humans as an antigen, we developed a polyclonal antibody designed as LID1 that specifically detected mLRRC52 and performed co-immunoprecipitation with mSLO3. Additionally, patch-clamp recordings of mouse sperm showed that, physiological activation of mKSper and sperm functions were dramatically attenuated after treatment with LID1, indicating that LID1 functionally disrupted the regulation of mLRRC52 on mKSper. Next, LID1 was used to investigate the significance of hLRRC52 for hKSper activation. As a result, hLRRC52 was expressed in human sperm and might be assembled with hSLO3. More importantly, LID1 inhibited hKSper currents and depolarized sperm membrane potential, supporting essential modulation of hLRRC52 in hKSper. Ca2+ signaling of human sperm was also compromised in the presence of LID1, which impaired sperm motility and acrosome reaction. Because LID1 specifically inhibited both mKSper and hKSper but not mCatSper or hCatSper, our results suggest that hLRRC52 functions as an important component of hKSper and regulates sperm physiological functions.
Collapse
Affiliation(s)
- Jiali Zhang
- Institute of Reproductive Medicine, School of Medicine, Nantong University, Nantong, Jiangsu, China
| | - Liping Zheng
- Institute of Life Science and School of Life Sciences, Nanchang University, Nanchang, Jiangxi, China
| | - Ying Chen
- Institute of Life Science and School of Life Sciences, Nanchang University, Nanchang, Jiangxi, China
| | - Tao Luo
- Institute of Life Science and School of Life Sciences, Nanchang University, Nanchang, Jiangxi, China
| | - Xuhui Zeng
- Institute of Reproductive Medicine, School of Medicine, Nantong University, Nantong, Jiangsu, China
| | - Hang Kang
- Institute of Reproductive Medicine, School of Medicine, Nantong University, Nantong, Jiangsu, China
| |
Collapse
|
3
|
Novero AG, Rodríguez PT, De la Vega Beltrán JL, Schiavi-Ehrenhaus LJ, Luque GM, Carruba M, Stival C, Gentile I, Ritagliati C, Santi CM, Nishigaki T, Krapf D, Buffone MG, Darszon A, Treviño CL, Krapf D. The sodium-proton exchangers sNHE and NHE1 control plasma membrane hyperpolarization in mouse sperm. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.04.583310. [PMID: 38496535 PMCID: PMC10942401 DOI: 10.1101/2024.03.04.583310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Sperm capacitation, crucial for fertilization, occurs in the female reproductive tract and can be replicated in vitro using a medium rich in bicarbonate, calcium, and albumin. These components trigger the cAMP-PKA signaling cascade, proposed to promote hyperpolarization of the mouse sperm plasma membrane through activation of SLO3 K+ channel. Hyperpolarization is a hallmark of capacitation: proper membrane hyperpolarization renders higher in vitro fertilizing ability, while Slo3 KO mice are infertile. However, the precise regulation of SLO3 opening remains elusive. Our study challenges the involvement of PKA in this event and reveals the role of Na+/H+ exchangers. During capacitation, calcium increase through CatSper channels activates NHE1, while cAMP directly stimulates the sperm-specific NHE, collectively promoting the alkalinization threshold needed for SLO3 opening. Hyperpolarization then feeds back Na+/H+ activity. Our work is supported by pharmacology, and a plethora of KO mouse models, and proposes a novel pathway leading to hyperpolarization.
Collapse
Affiliation(s)
- Analia G Novero
- Instituto de Biología Molecular y Celular de Rosario, CONICET-UNR, and Laboratorio de Medicina Reproductiva, Facultad de Ciencias Bioquímicas y Farmacéuticas, UNR, Rosario SF2000, Argentina
| | | | | | - Liz J Schiavi-Ehrenhaus
- Instituto de Bíologia y Medicina Experimental (IBYME-CONICET), Ciudad Autónoma de Buenos Aires, Argentina
| | - Guillermina M Luque
- Instituto de Bíologia y Medicina Experimental (IBYME-CONICET), Ciudad Autónoma de Buenos Aires, Argentina
| | - Micaela Carruba
- Instituto de Biología Molecular y Celular de Rosario, CONICET-UNR, and Laboratorio de Medicina Reproductiva, Facultad de Ciencias Bioquímicas y Farmacéuticas, UNR, Rosario SF2000, Argentina
| | - Cintia Stival
- Instituto de Biología Molecular y Celular de Rosario, CONICET-UNR, and Laboratorio de Medicina Reproductiva, Facultad de Ciencias Bioquímicas y Farmacéuticas, UNR, Rosario SF2000, Argentina
| | - Iñaki Gentile
- Instituto de Biología Molecular y Celular de Rosario, CONICET-UNR, and Laboratorio de Medicina Reproductiva, Facultad de Ciencias Bioquímicas y Farmacéuticas, UNR, Rosario SF2000, Argentina
| | - Carla Ritagliati
- Instituto de Biología Molecular y Celular de Rosario, CONICET-UNR, and Laboratorio de Medicina Reproductiva, Facultad de Ciencias Bioquímicas y Farmacéuticas, UNR, Rosario SF2000, Argentina
| | - Celia M Santi
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis Missouri 63110, USA
| | | | - Diego Krapf
- Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, CO 80526, USA
| | - Mariano G Buffone
- Instituto de Bíologia y Medicina Experimental (IBYME-CONICET), Ciudad Autónoma de Buenos Aires, Argentina
| | | | | | - Dario Krapf
- Instituto de Biología Molecular y Celular de Rosario, CONICET-UNR, and Laboratorio de Medicina Reproductiva, Facultad de Ciencias Bioquímicas y Farmacéuticas, UNR, Rosario SF2000, Argentina
| |
Collapse
|
4
|
Hughes MP. The cellular zeta potential: cell electrophysiology beyond the membrane. Integr Biol (Camb) 2024; 16:zyae003. [PMID: 38291769 DOI: 10.1093/intbio/zyae003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 12/16/2023] [Accepted: 01/06/2024] [Indexed: 02/01/2024]
Abstract
The standard model of the cell membrane potential Vm describes it as arising from diffusion currents across a membrane with a constant electric field, with zero electric field outside the cell membrane. However, the influence of Vm has been shown to extend into the extracellular space where it alters the cell's ζ-potential, the electrical potential measured a few nm from the cell surface which defines how the cell interacts with charged entities in its environment, including ions, molecules, and other cells. The paradigm arising from surface science is that the ζ-potential arises only from fixed membrane surface charge, and has consequently received little interest. However, if the ζ-potential can mechanistically and dynamically change by alteration of Vm, it allows the cell to dynamically alter cell-cell and cell-molecule interactions and may explain previously unexplained electrophysiological behaviours. Whilst the two potentials Vm and ζ are rarely reported together, they are occasionally described in different studies for the same cell type. By considering published data on these parameters across multiple cell types, as well as incidences of unexplained but seemingly functional Vm changes correlating with changes in cell behaviour, evidence is presented that this may play a functional role in the physiology of red blood cells, macrophages, platelets, sperm, ova, bacteria and cancer. Understanding how these properties will improve understanding of the role of electrical potentials and charges in the regulation of cell function and in the way in which cells interact with their environment. Insight The zeta (ζ) potential is the electrical potential a few nm beyond the surface of any suspensoid in water. Whilst typically assumed to arise only from fixed charges on the cell surface, recent and historical evidence shows a strong link to the cell's membrane potential Vm, which the cell can alter mechanistically through the use of ion channels. Whilst these two potentials have rarely been studied simultaneously, this review collates data across multiple studies reporting Vm, ζ-potential, electrical properties of changes in cell behaviour. Collectively, this points to Vm-mediated ζ-potential playing a significant role in the physiology and activity of blood cells, immune response, developmental biology and egg fertilization, and cancer among others.
Collapse
Affiliation(s)
- Michael Pycraft Hughes
- Department of Biomedical Engineering/Healthcare Engineering Innovation Centre (HEIC), Khalifa University, Abu Dhabi, UAE
| |
Collapse
|
5
|
Gardner CC, James PF. Na +/H + Exchangers (NHEs) in Mammalian Sperm: Essential Contributors to Male Fertility. Int J Mol Sci 2023; 24:14981. [PMID: 37834431 PMCID: PMC10573352 DOI: 10.3390/ijms241914981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 10/03/2023] [Accepted: 10/04/2023] [Indexed: 10/15/2023] Open
Abstract
Na+/H+ exchangers (NHEs) are known to be important regulators of pH in multiple intracellular compartments of eukaryotic cells. Sperm function is especially dependent on changes in pH and thus it has been postulated that NHEs play important roles in regulating the intracellular pH of these cells. For example, in order to achieve fertilization, mature sperm must maintain a basal pH in the male reproductive tract and then alkalize in response to specific signals in the female reproductive tract during the capacitation process. Eight NHE isoforms are expressed in mammalian testis/sperm: NHE1, NHE3, NHE5, NHE8, NHA1, NHA2, NHE10, and NHE11. These NHE isoforms are expressed at varying times during spermatogenesis and localize to different subcellular structures in developing and mature sperm where they contribute to multiple aspects of sperm physiology and male fertility including proper sperm development/morphogenesis, motility, capacitation, and the acrosome reaction. Previous work has provided evidence for NHE3, NHE8, NHA1, NHA2, and NHE10 being critical for male fertility in mice and NHE10 has recently been shown to be essential for male fertility in humans. In this article we review what is known about each NHE isoform expressed in mammalian sperm and discuss the physiological significance of each NHE isoform with respect to male fertility.
Collapse
Affiliation(s)
| | - Paul F. James
- Department of Biology, Miami University, Oxford, OH 45056, USA;
| |
Collapse
|
6
|
Lyon MD, Ferreira JJ, Li P, Bhagwat S, Butler A, Anderson K, Polo M, Santi CM. SLO3: A Conserved Regulator of Sperm Membrane Potential. Int J Mol Sci 2023; 24:11205. [PMID: 37446382 DOI: 10.3390/ijms241311205] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 07/03/2023] [Accepted: 07/05/2023] [Indexed: 07/15/2023] Open
Abstract
Sperm cells must undergo a complex maturation process after ejaculation to be able to fertilize an egg. One component of this maturation is hyperpolarization of the membrane potential to a more negative value. The ion channel responsible for this hyperpolarization, SLO3, was first cloned in 1998, and since then much progress has been made to determine how the channel is regulated and how its function intertwines with various signaling pathways involved in sperm maturation. Although Slo3 was originally thought to be present only in the sperm of mammals, recent evidence suggests that a primordial form of the gene is more widely expressed in some fish species. Slo3, like many reproductive genes, is rapidly evolving with low conservation between closely related species and different regulatory and pharmacological profiles. Despite these differences, SLO3 appears to have a conserved role in regulating sperm membrane potential and driving large changes in response to stimuli. The effect of this hyperpolarization of the membrane potential may vary among mammalian species just as the regulation of the channel does. Recent discoveries have elucidated the role of SLO3 in these processes in human sperm and provided tools to target the channel to affect human fertility.
Collapse
Affiliation(s)
- Maximilian D Lyon
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Juan J Ferreira
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Ping Li
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Shweta Bhagwat
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Alice Butler
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Kelsey Anderson
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Maria Polo
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Celia M Santi
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO 63110, USA
| |
Collapse
|
7
|
Keller A, Kerns K. Sperm capacitation as a predictor of boar fertility. Mol Reprod Dev 2023; 90:594-600. [PMID: 37306038 DOI: 10.1002/mrd.23690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 05/13/2023] [Accepted: 05/18/2023] [Indexed: 06/13/2023]
Abstract
Prediction of a boar's fertility level has great economic importance for sow herds. After standard sperm morphology and motility metrics are met, approximately 25% of boars have less than 80% conception rates. Due in part to the many factors involved in the fertilization process, a multifactorial model incorporating multiple relevant sperm physiology factors will likely lead to increased understanding of boar fertility. Here we review the current literature on boar sperm capacitation as a predictor of boar fertility. While limited, several studies have provided correlations between the percentage of sperm in an ejaculate that are capable of undergoing sperm capacitation in a chemically defined media and artificial insemination field fertility as well as proteome and other methods. Work summarized here underscores the need for further understanding of boar fertility.
Collapse
Affiliation(s)
- Alexandra Keller
- Department of Animal Science, Iowa State University, Ames, Iowa, USA
| | - Karl Kerns
- Department of Animal Science, Iowa State University, Ames, Iowa, USA
| |
Collapse
|
8
|
Cooray A, Kim J, Nirujan BR, Jayathilake NJ, Lee KP. Pharmacological Evidence Suggests That Slo3 Channel Is the Principal K + Channel in Boar Spermatozoa. Int J Mol Sci 2023; 24:ijms24097806. [PMID: 37175513 PMCID: PMC10178124 DOI: 10.3390/ijms24097806] [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: 03/31/2023] [Revised: 04/20/2023] [Accepted: 04/23/2023] [Indexed: 05/15/2023] Open
Abstract
Sperm ion channels are associated with the quality and type of flagellar movement, and their differential regulation is crucial for sperm function during specific phases. The principal potassium ion channel is responsible for the majority of K+ ion flux, resulting in membrane hyperpolarization, and is essential for sperm capacitation-related signaling pathways. The molecular identity of the principal K+ channel varies greatly between different species, and there is a lack of information about boar K+ channels. We aimed to determine the channel identity of boar sperm contributing to the primary K+ current using pharmacological dissection. A series of Slo1 and Slo3 channel modulators were used for treatment. Sperm motility and related kinematic parameters were monitored using a computer-assisted sperm analysis system under non-capacitated conditions. Time-lapse flow cytometry with fluorochromes was used to measure changes in different intracellular ionic concentrations, and conventional flow cytometry was used to determine the acrosome reaction. Membrane depolarization, reduction in acrosome reaction, and motility parameters were observed upon the inhibition of the Slo3 channel, suggesting that the Slo3 gene encodes the main K+ channel in boar spermatozoa. The Slo3 channel was localized on the sperm flagellum, and the inhibition of Slo3 did not reduce sperm viability. These results may aid potential animal-model-based extrapolations and help to ameliorate motility and related parameters, leading to improved assisted reproductive methods in industrial livestock production.
Collapse
Affiliation(s)
- Akila Cooray
- Department of Physiology, College of Veterinary Medicine, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Jeongsook Kim
- Department of Physiology, College of Veterinary Medicine, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Beno Ramesh Nirujan
- Department of Physiology, College of Veterinary Medicine, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Nishani Jayanika Jayathilake
- Department of Physiology, College of Veterinary Medicine, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Kyu Pil Lee
- Department of Physiology, College of Veterinary Medicine, Chungnam National University, Daejeon 34134, Republic of Korea
| |
Collapse
|
9
|
The SLC9C2 Gene Product (Na+/H+ Exchanger Isoform 11; NHE11) Is a Testis-Specific Protein Localized to the Head of Mature Mammalian Sperm. Int J Mol Sci 2023; 24:ijms24065329. [PMID: 36982403 PMCID: PMC10049371 DOI: 10.3390/ijms24065329] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 03/02/2023] [Accepted: 03/07/2023] [Indexed: 03/14/2023] Open
Abstract
Na+/H+ exchangers (NHEs) are a family of ion transporters that regulate the pH of various cell compartments across an array of cell types. In eukaryotes, NHEs are encoded by the SLC9 gene family comprising 13 genes. SLC9C2, which encodes the NHE11 protein, is the only one of the SLC9 genes that is essentially uncharacterized. Here, we show that SLC9C2 exhibits testis/sperm-restricted expression in rats and humans, akin to its paralog SLC9C1 (NHE10). Similar to NHE10, NHE11 is predicted to contain an NHE domain, a voltage sensing domain, and finally an intracellular cyclic nucleotide binding domain. An immunofluorescence analysis of testis sections reveals that NHE11 localizes with developing acrosomal granules in spermiogenic cells in both rat and human testes. Most interestingly, NHE11 localizes to the sperm head, likely the plasma membrane overlaying the acrosome, in mature sperm from rats and humans. Therefore, NHE11 is the only known NHE to localize to the acrosomal region of the head in mature sperm cells. The physiological role of NHE11 has yet to be demonstrated but its predicted functional domains and unique localization suggests that it could modulate intracellular pH of the sperm head in response to changes in membrane potential and cyclic nucleotide concentrations that are a result of sperm capacitation events. If NHE11 is shown to be important for male fertility, it will be an attractive target for male contraceptive drugs due to its exclusive testis/sperm-specific expression.
Collapse
|
10
|
Lyon M, Li P, Ferreira JJ, Lazarenko RM, Kharade SV, Kramer M, McClenahan SJ, Days E, Bauer JA, Spitznagel BD, Weaver CD, Borrego Alvarez A, Puga Molina LC, Lybaert P, Khambekar S, Liu A, Lindsley CW, Denton J, Santi CM. A selective inhibitor of the sperm-specific potassium channel SLO3 impairs human sperm function. Proc Natl Acad Sci U S A 2023; 120:e2212338120. [PMID: 36649421 PMCID: PMC9942793 DOI: 10.1073/pnas.2212338120] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 12/12/2022] [Indexed: 01/19/2023] Open
Abstract
To fertilize an oocyte, the membrane potential of both mouse and human sperm must hyperpolarize (become more negative inside). Determining the molecular mechanisms underlying this hyperpolarization is vital for developing new contraceptive methods and detecting causes of idiopathic male infertility. In mouse sperm, hyperpolarization is caused by activation of the sperm-specific potassium (K+) channel SLO3 [C. M. Santi et al., FEBS Lett. 584, 1041-1046 (2010)]. In human sperm, it has long been unclear whether hyperpolarization depends on SLO3 or the ubiquitous K+ channel SLO1 [N. Mannowetz, N. M. Naidoo, S. A. S. Choo, J. F. Smith, P. V. Lishko, Elife 2, e01009 (2013), C. Brenker et al., Elife 3, e01438 (2014), and S. A. Mansell, S. J. Publicover, C. L. R. Barratt, S. M. Wilson, Mol. Hum. Reprod. 20, 392-408 (2014)]. In this work, we identified the first selective inhibitor for human SLO3-VU0546110-and showed that it completely blocked heterologous SLO3 currents and endogenous K+ currents in human sperm. This compound also prevented sperm from hyperpolarizing and undergoing hyperactivated motility and induced acrosome reaction, which are necessary to fertilize an egg. We conclude that SLO3 is the sole K+ channel responsible for hyperpolarization and significantly contributes to the fertilizing ability of human sperm. Moreover, SLO3 is a good candidate for contraceptive development, and mutation of this gene is a possible cause of idiopathic male infertility.
Collapse
Affiliation(s)
- Maximilian Lyon
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO63110
| | - Ping Li
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO63110
| | - Juan J. Ferreira
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO63110
| | - Roman M. Lazarenko
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN37232
| | - Sujay V. Kharade
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN37232
| | - Meghan Kramer
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN37232
| | | | - Emily Days
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN37232
| | - Joshua A. Bauer
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN37232
| | | | - C. David Weaver
- Department of Pharmacology, Vanderbilt University, Nashville, TN37232
| | - Aluet Borrego Alvarez
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO63110
| | - Lis C. Puga Molina
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO63110
| | - Pascale Lybaert
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO63110
- Laboratoire de recherche en Reproduction humaine, Université Libre de Bruxelles, Bruxelles1050, Belgium
| | - Saayli Khambekar
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO63110
| | - Alicia Liu
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO63110
| | - Craig W. Lindsley
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN37232
- Department of Pharmacology, Vanderbilt University, Nashville, TN37232
| | - Jerod Denton
- Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, TN37232
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN37232
- Department of Pharmacology, Vanderbilt University, Nashville, TN37232
| | - Celia M. Santi
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO63110
| |
Collapse
|
11
|
Çakır Gündoğdu A, Take Kaplanoğlu G, Ören S, Baykal B, Korkmaz C, Gümüşlü S, Karabacak RO. Impact of 5'-AMP-activated protein kinase (AMPK) on Epithelial Sodium Channels (ENaCs) in human sperm. Tissue Cell 2022; 78:101896. [DOI: 10.1016/j.tice.2022.101896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Revised: 07/27/2022] [Accepted: 08/08/2022] [Indexed: 10/15/2022]
|
12
|
Prajapati P, Kane S, McBrinn RC, Dean MS, Martins da Silva SJ, Brown SG. Elevated and Sustained Intracellular Calcium Signalling Is Necessary for Efficacious Induction of the Human Sperm Acrosome Reaction. Int J Mol Sci 2022; 23:ijms231911253. [PMID: 36232560 PMCID: PMC9570455 DOI: 10.3390/ijms231911253] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 09/13/2022] [Accepted: 09/16/2022] [Indexed: 11/16/2022] Open
Abstract
Progesterone and prostaglandin E1 are postulated to trigger the human sperm acrosome reaction (AR). However, their reported efficacy is very variable which likely, in part, reflects the plethora of experimental conditions and methodologies used to detect this physiologically relevant event. The purpose of this study was to develop an assay for the robust induction and objective measurement of the complete AR. Sperm from healthy volunteers or patients undertaking IVF were treated with a variety of ligands (progesterone, prostaglandin E1 or NH4Cl, alone or in combinations). AR, motility and intracellular calcium measurements were measured using flow cytometry, computer-assisted sperm analysis (CASA) and fluorimetry, respectively. The AR was significantly increased by the simultaneous application of progesterone, prostaglandin E1 and NH4Cl, following an elevated and sustained intracellular calcium concentration. However, we observed notable inter- and intra-donor sample heterogeneity of the AR induction. When studying the patient samples, we found no relationship between the IVF fertilization rate and the AR. We conclude that progesterone and prostaglandin E1 alone do not significantly increase the percentage of live acrosome-reacted sperm. This assay has utility for drug discovery and sperm toxicology studies but is not predictive for IVF success.
Collapse
Affiliation(s)
- Priyanka Prajapati
- Reproductive Medicine Research Group, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK
| | - Shruti Kane
- School of Applied Sciences, Abertay University, Dundee DD1 1HG, UK
| | | | - Morven S. Dean
- Reproductive Medicine Research Group, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK
- Assisted Conception Unit, Ninewells Hospital, Dundee DD1 9SY, UK
| | - Sarah J. Martins da Silva
- Reproductive Medicine Research Group, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK
- Assisted Conception Unit, Ninewells Hospital, Dundee DD1 9SY, UK
- Correspondence:
| | - Sean G. Brown
- School of Applied Sciences, Abertay University, Dundee DD1 1HG, UK
| |
Collapse
|
13
|
Panchal D, Bhagwat S, Parte P. N-Formyl-L-aspartate mediates chemotaxis in sperm via the beta-2-adrenergic receptor. Front Cell Dev Biol 2022; 10:959094. [PMID: 36211455 PMCID: PMC9538769 DOI: 10.3389/fcell.2022.959094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 08/31/2022] [Indexed: 11/16/2022] Open
Abstract
Chemotaxis is a highly conserved physiological event required for directed sperm movement during fertilization. Recently, studies from our laboratory have identified N-formyl-L-aspartate (NFA) as a sperm chemoattractant. NFA is a known agonist for the beta-2-adrenergic receptor (β-2-AR) that regulates cAMP production and Ca2+ mobilization in somatic cells. As these downstream signaling molecules are also reported to be involved in sperm chemotaxis, in the present study we investigated the putative mechanism/s by which NFA may mediate chemotaxis. Toward this, the expression and localization of β-2-AR in sperm were studied by Western blot and indirect immunofluorescence, respectively. The responses of sperm to various concentration gradients of NFA and ICI-118,551, a β-2-AR specific antagonist, were evaluated using the microfluidics device-based chemotaxis assay. The intracellular concentration of Ca2+, on exposure to NFA, was analyzed using FURA-2 AM-based fluorimetric assay. Furthermore, the effect of NFA on sperm capacitation and acrosome reaction was evaluated using Western blot and immunofluorescence. NFA exhibited a bell-shaped dose-response curve typical of chemotaxis, with maximum response observed at 0.01M NFA, beyond which it was inhibitory; β-2-AR localization was seen on the sperm head and the mid-piece region of the flagella. Inhibition of sperm chemotaxis by ICI-118,551 confirms that sperm respond chemotactically to NFA via β-2-AR. Interestingly, at the concentration used for chemotaxis, NFA induced an increase in the intracellular Ca2+ but decreased cAMP in capacitating sperm. However, NFA per se did not induce capacitation as seen from the lack of effect on tyrosine phosphorylation and membrane potential of uncapacitated sperm. Acrosome evaluation of NFA-treated sperm using PSA-FITC staining showed no effect on the acrosome structure. Our data thus provide evidence indicating that NFA induces sperm chemotaxis and the chemotactic response of sperm to NFA from the ovulatory phase of oviductal fluid is mediated through the β-2-AR on sperm possibly via non-canonical signaling.
Collapse
Affiliation(s)
- Durva Panchal
- Department of Gamete Immunobiology, ICMR-National Institute for Research in Reproductive and Child Health, Mumbai, Maharashtra, India
| | - Shweta Bhagwat
- Department of Gamete Immunobiology, ICMR-National Institute for Research in Reproductive and Child Health, Mumbai, Maharashtra, India
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO, United States
| | - Priyanka Parte
- Department of Gamete Immunobiology, ICMR-National Institute for Research in Reproductive and Child Health, Mumbai, Maharashtra, India
- *Correspondence: Priyanka Parte,
| |
Collapse
|
14
|
Balestrini PA, Sanchez-Cardenas C, Luque GM, Baro Graf C, Sierra JM, Hernández-Cruz A, Visconti PE, Krapf D, Darszon A, Buffone MG. Membrane hyperpolarization abolishes calcium oscillations that prevent induced acrosomal exocytosis in human sperm. FASEB J 2021; 35:e21478. [PMID: 33991146 DOI: 10.1096/fj.202002333rr] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 02/09/2021] [Accepted: 02/11/2021] [Indexed: 12/14/2022]
Abstract
Sperm capacitation is essential to gain fertilizing capacity. During this process, a series of biochemical and physiological modifications occur that allow sperm to undergo acrosomal exocytosis (AE). At the molecular level, hyperpolarization of the sperm membrane potential (Em) takes place during capacitation. This study shows that human sperm incubated under conditions that do not support capacitation (NC) can become ready for an agonist stimulated AE by pharmacologically inducing Em hyperpolarization with Valinomycin or Amiloride. To investigate how Em hyperpolarization promotes human sperm's ability to undergo AE, live single-cell imaging experiments were performed to simultaneously monitor changes in [Ca2+ ]i and the occurrence of AE. Em hyperpolarization turned [Ca2+ ]i dynamics in NC sperm from spontaneously oscillating into a sustained slow [Ca2+ ]i increase. The addition of progesterone (P4) or K+ to Valinomycin-treated sperm promoted that a significant number of cells displayed a transitory rise in [Ca2+ ]i which then underwent AE. Altogether, our results demonstrate that Em hyperpolarization is necessary and sufficient to prepare human sperm for the AE. Furthermore, this Em change decreased Ca2+ oscillations that block the occurrence of AE, providing strong experimental evidence of the molecular mechanism that drives the acquisition of acrosomal responsiveness.
Collapse
Affiliation(s)
- Paula A Balestrini
- Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Claudia Sanchez-Cardenas
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, México
| | - Guillermina M Luque
- Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Carolina Baro Graf
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México (UNAM) Ciudad Universitaria, Ciudad de México, México
| | - Jessica M Sierra
- Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Arturo Hernández-Cruz
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México (UNAM) Ciudad Universitaria, Ciudad de México, México
| | - Pablo E Visconti
- Department of Veterinary and Animal Science, Paige Labs, University of Massachusetts, Amherst, MA, USA
| | - Dario Krapf
- Instituto de Biología Molecular y Celular de Rosario (CONICET-UNR), Rosario, Argentina
| | - Alberto Darszon
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, México
| | - Mariano G Buffone
- Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| |
Collapse
|
15
|
Mendoza N, Casao A, Domingo J, Quintín F, Laviña A, Fantova E, Cebrián-Pérez JÁ, Muiño-Blanco T, Pérez-Pe R. Influence of Non-conventional Sperm Quality Parameters on Field Fertility in Ovine. Front Vet Sci 2021; 8:650572. [PMID: 34026889 PMCID: PMC8139619 DOI: 10.3389/fvets.2021.650572] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 04/06/2021] [Indexed: 12/04/2022] Open
Abstract
The prediction of the fertilizing ability of a seminal dose continues to be a primary aim in the field of artificial insemination (AI). To achieve this goal, in this study we have included the evaluation of some non-conventional sperm quality markers. A total of 3,906 ewes from 52 different farms were inseminated with 357 refrigerated seminal doses obtained from 45 mature Rasa Aragonesa rams. The same samples were used for sperm quality analysis including membrane integrity, capacitation status, oxygen consumption and apoptotic-like markers such as phosphatidylserine translocation (PS), plasmalemma disorganization/mitochondrial membrane potential, caspase activation and DNA damage. Seminal doses from the breeding (B) season presented higher percentages of intact membrane (IM), non permeant (NP) membrane with high mitochondrial membrane potential (ΔΨm) and IM without PS translocation spermatozoa than those from the non-breeding (NB) season. Therefore, we can conclude that there were less spermatozoa showing apoptotic-like features in the seminal doses from the B than the NB season, although these differences did not affect field fertility. Only the percentage of intact membrane, non-capacitated (IM-NC) spermatozoa showed a significant correlation with in vivo fertility (P = 0.005) and fecundity (P = 0.007) values obtained after cervical AI when all data were evaluated. When the data were sorted by season and distance to the farms where AI was performed, the correlation between the percentage of IM-NC spermatozoa and reproductive parameters increased in the NB season and progressively with remoteness from the farms. Some other sperm parameters, like NP with high ΔΨm, IM sperm without active caspases and DNA-intact spermatozoa, also showed significant correlations with the reproductive parameters in the sorted data. Moreover, the increment in both the percentage of IM-NC and DNA-intact spermatozoa would increase the probability of obtaining a fertility higher than the mean (>52%), as revealed by a multiple logistic regression analysis. In conclusion, we have identified two seminal markers—the percentage of intact membrane, non-capacitated spermatozoa, and DNA intact spermatozoa—which could be used as a test to discard males in AI programs, which is highly important from an economic point of view and can contribute to achieving satisfactory fertility rates.
Collapse
Affiliation(s)
- Noelia Mendoza
- Grupo BIOFITER-Departamento de Bioquímica y Biología Molecular y Celular-Instituto Universitario de Investigación en Ciencias Ambientales de Aragón (IUCA), Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain
| | - Adriana Casao
- Grupo BIOFITER-Departamento de Bioquímica y Biología Molecular y Celular-Instituto Universitario de Investigación en Ciencias Ambientales de Aragón (IUCA), Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain
| | - Juan Domingo
- Grupo BIOFITER-Departamento de Bioquímica y Biología Molecular y Celular-Instituto Universitario de Investigación en Ciencias Ambientales de Aragón (IUCA), Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain
| | - Francisco Quintín
- Centro de Transferencia Agroalimentaria (Gobierno de Aragón), Zaragoza, Spain
| | - Adolfo Laviña
- Asociación nacional de criadores de ganado ovino de la raza rasa aragonesa (ANGRA), Zaragoza, Spain
| | - Enrique Fantova
- Unión de Productores de Raza Rasa Aragonesa (UPRA)-Grupo Pastores, Zaragoza, Spain
| | - José Álvaro Cebrián-Pérez
- Grupo BIOFITER-Departamento de Bioquímica y Biología Molecular y Celular-Instituto Universitario de Investigación en Ciencias Ambientales de Aragón (IUCA), Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain
| | - Teresa Muiño-Blanco
- Grupo BIOFITER-Departamento de Bioquímica y Biología Molecular y Celular-Instituto Universitario de Investigación en Ciencias Ambientales de Aragón (IUCA), Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain
| | - Rosaura Pérez-Pe
- Grupo BIOFITER-Departamento de Bioquímica y Biología Molecular y Celular-Instituto Universitario de Investigación en Ciencias Ambientales de Aragón (IUCA), Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain
| |
Collapse
|
16
|
Magdanz V, Vivaldi J, Mohanty S, Klingner A, Vendittelli M, Simmchen J, Misra S, Khalil ISM. Impact of Segmented Magnetization on the Flagellar Propulsion of Sperm-Templated Microrobots. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2004037. [PMID: 33898186 PMCID: PMC8061355 DOI: 10.1002/advs.202004037] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 12/17/2020] [Indexed: 05/22/2023]
Abstract
Technical design features for improving the way a passive elastic filament produces propulsive thrust can be understood by analyzing the deformation of sperm-templated microrobots with segmented magnetization. Magnetic nanoparticles are electrostatically self-assembled on bovine sperm cells with nonuniform surface charge, producing different categories of sperm-templated microrobots. Depending on the amount and location of the nanoparticles on each cellular segment, magnetoelastic and viscous forces determine the wave pattern of each category during flagellar motion. Passively propagating waves are induced along the length of these microrobots using external rotating magnetic fields and the resultant wave patterns are measured. The response of the microrobots to the external field reveals distinct flow fields, propulsive thrust, and frequency responses during flagellar propulsion. This work allows predictions for optimizing the design and propulsion of flexible magnetic microrobots with segmented magnetization.
Collapse
Affiliation(s)
- Veronika Magdanz
- Applied ZoologyTechnical University of DresdenDresden01069Germany
- Smart Nano‐Bio‐Devices GroupInstitute for Bioengineering of CataloniaBarcelona08028Spain
| | - Jacopo Vivaldi
- Department of Computer Control and Management EngineeringSapienza University of RomeRome00185Italy
| | - Sumit Mohanty
- Surgical Robotics LaboratoryDepartment of Biomechanical EngineeringUniversity of TwenteEnschede7522 NBThe Netherlands
| | - Anke Klingner
- Department of PhysicsThe German University in CairoNew Cairo13411Egypt
| | - Marilena Vendittelli
- Department of Computer Control and Management EngineeringSapienza University of RomeRome00185Italy
| | - Juliane Simmchen
- Physical ChemistryTechnical University of DresdenDresden01069Germany
| | - Sarthak Misra
- Surgical Robotics LaboratoryDepartment of Biomechanical EngineeringUniversity of TwenteEnschede7522 NBThe Netherlands
- Surgical Robotics LaboratoryDepartment of Biomedical EngineeringUniversity of Groningen and University Medical Center GroningenGroningen9713 GZThe Netherlands
| | - Islam S. M. Khalil
- Surgical Robotics LaboratoryDepartment of Biomechanical EngineeringUniversity of TwenteEnschede7522 NBThe Netherlands
| |
Collapse
|
17
|
Kang H, Liu M, Zhang W, Huang RZ, Zhao N, Chen C, Zeng XH. Na +/H + Exchangers Involve in Regulating the pH-Sensitive Ion Channels in Mouse Sperm. Int J Mol Sci 2021; 22:ijms22041612. [PMID: 33562644 PMCID: PMC7914462 DOI: 10.3390/ijms22041612] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/02/2021] [Accepted: 02/03/2021] [Indexed: 12/20/2022] Open
Abstract
Sperm-specific K+ ion channel (KSper) and Ca2+ ion channel (CatSper), whose elimination causes male infertility in mice, determine the membrane potential and Ca2+ influx, respectively. KSper and CatSper can be activated by cytosolic alkalization, which occurs during sperm going through the alkaline environment of the female reproductive tract. However, which intracellular pH (pHi) regulator functionally couples to the activation of KSper/CatSper remains obscure. Although Na+/H+ exchangers (NHEs) have been implicated to mediate pHi in sperm, there is a lack of direct evidence confirming the functional coupling between NHEs and KSper/CatSper. Here, 5-(N,N-dimethyl)-amiloride (DMA), an NHEs inhibitor that firstly proved not to affect KSper/CatSper directly, was chosen to examine NHEs function on KSper/CatSper in mouse sperm. The results of patch clamping recordings showed that, when extracellular pH was at the physiological level of 7.4, DMA application caused KSper inhibition and the depolarization of membrane potential when pipette solutions were not pH-buffered. In contrast, these effects were minimized when pipette solutions were pH-buffered, indicating that they solely resulted from pHi acidification caused by NHEs inhibition. Similarly, DMA treatment reduced CatSper current and intracellular Ca2+, effects also dependent on the buffer capacity of pH in pipette solutions. The impairment of sperm motility was also observed after DMA incubation. These results manifested that NHEs activity is coupled to the activation of KSper/CatSper under physiological conditions.
Collapse
Affiliation(s)
- Hang Kang
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang 330031, Jiangxi, China; (H.K.); (M.L.); (W.Z.); (N.Z.)
| | - Min Liu
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang 330031, Jiangxi, China; (H.K.); (M.L.); (W.Z.); (N.Z.)
| | - Wei Zhang
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang 330031, Jiangxi, China; (H.K.); (M.L.); (W.Z.); (N.Z.)
| | - Rong-Zu Huang
- Institute of Reproductive Medicine, School of Medicine, Nantong University, Nantong 226019, Jiangsu, China; (R.-Z.H.); (C.C.)
| | - Na Zhao
- Institute of Life Science and School of Life Science, Nanchang University, Nanchang 330031, Jiangxi, China; (H.K.); (M.L.); (W.Z.); (N.Z.)
| | - Chen Chen
- Institute of Reproductive Medicine, School of Medicine, Nantong University, Nantong 226019, Jiangsu, China; (R.-Z.H.); (C.C.)
| | - Xu-Hui Zeng
- Institute of Reproductive Medicine, School of Medicine, Nantong University, Nantong 226019, Jiangsu, China; (R.-Z.H.); (C.C.)
- Correspondence: ; Tel.: +86-177-6196-0066
| |
Collapse
|
18
|
Machine-learning algorithm incorporating capacitated sperm intracellular pH predicts conventional in vitro fertilization success in normospermic patients. Fertil Steril 2021; 115:930-939. [PMID: 33461755 DOI: 10.1016/j.fertnstert.2020.10.038] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 10/06/2020] [Accepted: 10/08/2020] [Indexed: 12/24/2022]
Abstract
OBJECTIVE To measure human sperm intracellular pH (pHi) and develop a machine-learning algorithm to predict successful conventional in vitro fertilization (IVF) in normospermic patients. DESIGN Spermatozoa from 76 IVF patients were capacitated in vitro. Flow cytometry was used to measure sperm pHi, and computer-assisted semen analysis was used to measure hyperactivated motility. A gradient-boosted machine-learning algorithm was trained on clinical data and sperm pHi and membrane potential from 58 patients to predict successful conventional IVF, defined as a fertilization ratio (number of fertilized oocytes [2 pronuclei]/number of mature oocytes) greater than 0.66. The algorithm was validated on an independent set of data from 18 patients. SETTING Academic medical center. PATIENT(S) Normospermic men undergoing IVF. Patients were excluded if they used frozen sperm, had known male factor infertility, or used intracytoplasmic sperm injection only. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Successful conventional IVF. RESULT(S) Sperm pHi positively correlated with hyperactivated motility and with conventional IVF ratio (n = 76) but not with intracytoplasmic sperm injection fertilization ratio (n = 38). In receiver operating curve analysis of data from the test set (n = 58), the machine-learning algorithm predicted successful conventional IVF with a mean accuracy of 0.72 (n = 18), a mean area under the curve of 0.81, a mean sensitivity of 0.65, and a mean specificity of 0.80. CONCLUSION(S) Sperm pHi correlates with conventional fertilization outcomes in normospermic patients undergoing IVF. A machine-learning algorithm can use clinical parameters and markers of capacitation to accurately predict successful fertilization in normospermic men undergoing conventional IVF.
Collapse
|
19
|
Matamoros-Volante A, Castillo-Viveros V, Torres-Rodríguez P, Treviño MB, Treviño CL. Time-Lapse Flow Cytometry: A Robust Tool to Assess Physiological Parameters Related to the Fertilizing Capability of Human Sperm. Int J Mol Sci 2020; 22:ijms22010093. [PMID: 33374265 PMCID: PMC7796328 DOI: 10.3390/ijms22010093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/16/2020] [Accepted: 12/16/2020] [Indexed: 11/17/2022] Open
Abstract
Plasma membrane (PM) hyperpolarization, increased intracellular pH (pHi), and changes in intracellular calcium concentration ([Ca2+]i) are physiological events that occur during human sperm capacitation. These parameters are potential predictors of successful outcomes for men undergoing artificial reproduction techniques (ARTs), but methods currently available for their determination pose various technical challenges and limitations. Here, we developed a novel strategy employing time-lapse flow cytometry (TLFC) to determine capacitation-related membrane potential (Em) and pHi changes, and progesterone-induced [Ca2+]i increases. Our results show that TLFC is a robust method to measure absolute Em and pHi values and to qualitatively evaluate [Ca2+]i changes. To support the usefulness of our methodology, we used sperm from two types of normozoospermic donors: known paternity (subjects with self-reported paternity) and no-known paternity (subjects without self-reported paternity and no known fertility problems). We found relevant differences between them. The incidences of membrane hyperpolarization, pHi alkalinization, and increased [Ca2+]i were consistently high among known paternity samples (100%, 100%, and 86%, respectively), while they varied widely among no-known paternity samples (44%, 17%, and 45%, respectively). Our results indicate that TLFC is a powerful tool to analyze key physiological parameters of human sperm, which pending clinical validation, could potentially be employed as fertility predictors.
Collapse
Affiliation(s)
- Arturo Matamoros-Volante
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca Morelos 62210, Mexico; (A.M.-V.); (V.C.-V.); (P.T.-R.)
| | - Valeria Castillo-Viveros
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca Morelos 62210, Mexico; (A.M.-V.); (V.C.-V.); (P.T.-R.)
| | - Paulina Torres-Rodríguez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca Morelos 62210, Mexico; (A.M.-V.); (V.C.-V.); (P.T.-R.)
| | - Marcela B. Treviño
- Science Department, School of Pure and Applied Sciences, Florida SouthWestern State College, Fort Myers, FL 33919, USA;
| | - Claudia L. Treviño
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca Morelos 62210, Mexico; (A.M.-V.); (V.C.-V.); (P.T.-R.)
- Correspondence: ; Tel.: +52-777-329-1611
| |
Collapse
|
20
|
Baro Graf C, Ritagliati C, Stival C, Luque GM, Gentile I, Buffone MG, Krapf D. Everything you ever wanted to know about PKA regulation and its involvement in mammalian sperm capacitation. Mol Cell Endocrinol 2020; 518:110992. [PMID: 32853743 DOI: 10.1016/j.mce.2020.110992] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 08/11/2020] [Accepted: 08/12/2020] [Indexed: 12/29/2022]
Abstract
The 3', 5'-cyclic adenosine monophosphate (cAMP) dependent protein kinase (PKA) is a tetrameric holoenzyme comprising a set of two regulatory subunits (PKA-R) and two catalytic (PKA-C) subunits. The PKA-R subunits act as sensors of cAMP and allow PKA-C activity. One of the first signaling events observed during mammalian sperm capacitation is PKA activation. Thus, understanding how PKA activity is restricted in space and time is crucial to decipher the critical steps of sperm capacitation. It is widely accepted that PKA specificity depends on several levels of regulation. Anchoring proteins play a pivotal role in achieving proper localization signaling, subcellular targeting and cAMP microdomains. These multi-factorial regulation steps are necessary for a precise spatio-temporal activation of PKA. Here we discuss recent understanding of regulatory mechanisms of PKA in mammalian sperm, such as post-translational modifications, in the context of its role as the master orchestrator of molecular events conducive to capacitation.
Collapse
Affiliation(s)
- Carolina Baro Graf
- Laboratory of Cell Signal Transduction Networks, Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET-UNR, Rosario, Argentina; Laboratorio de Medicina Reproductiva (LMR), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Carla Ritagliati
- Laboratory of Cell Signal Transduction Networks, Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET-UNR, Rosario, Argentina
| | - Cintia Stival
- Laboratory of Cell Signal Transduction Networks, Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET-UNR, Rosario, Argentina
| | - Guillermina M Luque
- Laboratory of Cellular and Molecular Reproductive Biology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Buenos Aires, Argentina
| | - Iñaki Gentile
- Laboratory of Cell Signal Transduction Networks, Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET-UNR, Rosario, Argentina
| | - Mariano G Buffone
- Laboratory of Cellular and Molecular Reproductive Biology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Buenos Aires, Argentina
| | - Dario Krapf
- Laboratory of Cell Signal Transduction Networks, Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET-UNR, Rosario, Argentina; Laboratorio de Medicina Reproductiva (LMR), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina.
| |
Collapse
|
21
|
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.
Collapse
|
22
|
Molina LCP, Gunderson S, Riley J, Lybaert P, Borrego-Alvarez A, Jungheim ES, Santi CM. Membrane Potential Determined by Flow Cytometry Predicts Fertilizing Ability of Human Sperm. Front Cell Dev Biol 2020; 7:387. [PMID: 32039203 PMCID: PMC6985285 DOI: 10.3389/fcell.2019.00387] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 12/20/2019] [Indexed: 11/26/2022] Open
Abstract
Infertility affects 10 to 15% of couples worldwide, with a male factor contributing up to 50% of these cases. The primary tool for diagnosing male infertility is traditional semen analysis, which reveals sperm concentration, morphology, and motility. However, 25% of infertile men are diagnosed as normozoospermic, meaning that, in many cases, normal-appearing sperm fail to fertilize an egg. Thus, new information regarding the mechanisms by which sperm acquire fertilizing ability is needed to develop a clinically feasible test that can predict sperm function failure. An important feature of sperm fertilization capability in many species is plasma membrane hyperpolarization (membrane potential becoming more negative inside) in response to signals from the egg or female genital tract. In mice, this hyperpolarization is necessary for sperm to undergo the changes in motility (hyperactivation) and acrosomal exocytosis required to fertilize an egg. Human sperm also hyperpolarize during capacitation, but the physiological relevance of this event has not been determined. Here, we used flow cytometry combined with a voltage-sensitive fluorescent probe to measure absolute values of human sperm membrane potential. We found that hyperpolarization of human sperm plasma membrane correlated positively with fertilizing ability. Hyperpolarized human sperm had higher in vitro fertilization (IVF) ratios and higher percentages of acrosomal exocytosis and hyperactivated motility than depolarized sperm. We propose that measurements of human sperm membrane potential could be used to diagnose men with idiopathic infertility and predict IVF success in normozoospermic infertile patients. Patients with depolarized values could be guided toward intracytoplasmic sperm injection, preventing unnecessary cycles of intrauterine insemination or IVF. Conversely, patients with hyperpolarized values of sperm membrane potential could undergo only conventional IVF, avoiding the risks and costs associated with intracytoplasmic sperm injection.
Collapse
Affiliation(s)
- Lis C. Puga Molina
- Department of Obstetrics & Gynecology, Washington University School of Medicine, St Louis, MO, United States
| | - Stephanie Gunderson
- Department of Obstetrics & Gynecology, Washington University School of Medicine, St Louis, MO, United States
| | - Joan Riley
- Department of Obstetrics & Gynecology, Washington University School of Medicine, St Louis, MO, United States
| | - Pascal Lybaert
- Laboratory of Experimental Hormonology, School of Medicine, Université Libre de Bruxelles, Brussels, Belgium
| | - Aluet Borrego-Alvarez
- Department of Obstetrics & Gynecology, Washington University School of Medicine, St Louis, MO, United States
| | - Emily S. Jungheim
- Department of Obstetrics & Gynecology, Washington University School of Medicine, St Louis, MO, United States
| | - Celia M. Santi
- Department of Obstetrics & Gynecology, Washington University School of Medicine, St Louis, MO, United States
| |
Collapse
|