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Kostritskaia Y, Klüssendorf M, Pan YE, Hassani Nia F, Kostova S, Stauber T. Physiological Functions of the Volume-Regulated Anion Channel VRAC/LRRC8 and the Proton-Activated Chloride Channel ASOR/TMEM206. Handb Exp Pharmacol 2024; 283:181-218. [PMID: 37468723 DOI: 10.1007/164_2023_673] [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] [Indexed: 07/21/2023]
Abstract
Volume-regulated anion channels (VRACs) and the acid-sensitive outwardly rectifying anion channel (ASOR) mediate flux of chloride and small organic anions. Although known for a long time, they were only recently identified at the molecular level. VRACs are heteromers consisting of LRRC8 proteins A to E. Combining the essential LRRC8A with different LRRC8 paralogues changes key properties of VRAC such as conductance or substrate selectivity, which is how VRACs are involved in multiple physiological functions including regulatory volume decrease, cell proliferation and migration, cell death, purinergic signalling, fat and glucose metabolism, insulin signalling, and spermiogenesis. VRACs are also involved in pathological conditions, such as the neurotoxic release of glutamate and aspartate. Certain VRACs are also permeable to larger, organic anions, including antibiotics and anti-cancer drugs, making them an interesting therapeutic target. ASOR, also named proton-activated chloride channel (PAC), is formed by TMEM206 homotrimers on the plasma membrane and on endosomal compartments where it mediates chloride flux in response to extracytosolic acidification and plays a role in the shrinking and maturation of macropinosomes. ASOR has been shown to underlie neuronal swelling which causes cell death after stroke as well as promoting the metastasis of certain cancers, making them intriguing therapeutic targets as well.
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Affiliation(s)
- Yulia Kostritskaia
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Malte Klüssendorf
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Yingzhou Edward Pan
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Fatemeh Hassani Nia
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Simona Kostova
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Tobias Stauber
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany.
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Chen L, König B, Liu T, Pervaiz S, Razzaque YS, Stauber T. More than just a pressure relief valve: physiological roles of volume-regulated LRRC8 anion channels. Biol Chem 2019; 400:1481-1496. [DOI: 10.1515/hsz-2019-0189] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 04/27/2019] [Indexed: 12/29/2022]
Abstract
Abstract
The volume-regulated anion channel (VRAC) is a key player in the volume regulation of vertebrate cells. This ubiquitously expressed channel opens upon osmotic cell swelling and potentially other cues and releases chloride and organic osmolytes, which contributes to regulatory volume decrease (RVD). A plethora of studies have proposed a wide range of physiological roles for VRAC beyond volume regulation including cell proliferation, differentiation and migration, apoptosis, intercellular communication by direct release of signaling molecules and by supporting the exocytosis of insulin. VRAC was additionally implicated in pathological states such as cancer therapy resistance and excitotoxicity under ischemic conditions. Following extensive investigations, 5 years ago leucine-rich repeat-containing family 8 (LRRC8) heteromers containing LRRC8A were identified as the pore-forming components of VRAC. Since then, molecular biological approaches have allowed further insight into the biophysical properties and structure of VRAC. Heterologous expression, siRNA-mediated downregulation and genome editing in cells, as well as the use of animal models have enabled the assessment of the proposed physiological roles, together with the identification of new functions including spermatogenesis and the uptake of antibiotics and platinum-based cancer drugs. This review discusses the recent molecular biological insights into the physiology of VRAC in relation to its previously proposed roles.
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Affiliation(s)
- Lingye Chen
- Institut für Chemie und Biochemie , Freie Universität Berlin , Thielallee 63 , D-14195 Berlin , Germany
| | - Benjamin König
- Institut für Chemie und Biochemie , Freie Universität Berlin , Thielallee 63 , D-14195 Berlin , Germany
| | - Tianbao Liu
- Institut für Chemie und Biochemie , Freie Universität Berlin , Thielallee 63 , D-14195 Berlin , Germany
| | - Sumaira Pervaiz
- Institut für Chemie und Biochemie , Freie Universität Berlin , Thielallee 63 , D-14195 Berlin , Germany
| | - Yasmin S. Razzaque
- Institut für Chemie und Biochemie , Freie Universität Berlin , Thielallee 63 , D-14195 Berlin , Germany
| | - Tobias Stauber
- Institut für Chemie und Biochemie , Freie Universität Berlin , Thielallee 63 , D-14195 Berlin , Germany
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Bao J, Perez CJ, Kim J, Zhang H, Murphy CJ, Hamidi T, Jaubert J, Platt CD, Chou J, Deng M, Zhou MH, Huang Y, Gaitán-Peñas H, Guénet JL, Lin K, Lu Y, Chen T, Bedford MT, Dent SY, Richburg JH, Estévez R, Pan HL, Geha RS, Shi Q, Benavides F. Deficient LRRC8A-dependent volume-regulated anion channel activity is associated with male infertility in mice. JCI Insight 2018; 3:99767. [PMID: 30135305 DOI: 10.1172/jci.insight.99767] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 07/11/2018] [Indexed: 01/06/2023] Open
Abstract
Ion channel-controlled cell volume regulation is of fundamental significance to the physiological function of sperm. In addition to volume regulation, LRRC8A-dependent volume-regulated anion channel (VRAC) activity is involved in cell cycle progression, insulin signaling, and cisplatin resistance. Nevertheless, the contribution of LRRC8A and its dependent VRAC activity in the germ cell lineage remain unknown. By utilizing a spontaneous Lrrc8a mouse mutation (c.1325delTG, p.F443*) and genetically engineered mouse models, we demonstrate that LRRC8A-dependent VRAC activity is essential for male germ cell development and fertility. Lrrc8a-null male germ cells undergo progressive degeneration independent of the apoptotic pathway during postnatal testicular development. Lrrc8a-deficient mouse sperm exhibit multiple morphological abnormalities of the flagella (MMAF), a feature commonly observed in the sperm of infertile human patients. Importantly, we identified a human patient with a rare LRRC8A hypomorphic mutation (c.1634G>A, p.Arg545His) possibly linked to Sertoli cell-only syndrome (SCOS), a male sterility disorder characterized by the loss of germ cells. Thus, LRRC8A is a critical factor required for germ cell development and volume regulation in the mouse, and it might serve as a novel diagnostic and therapeutic target for SCOS patients.
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Affiliation(s)
- Jianqiang Bao
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, Texas, USA
| | - Carlos J Perez
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, Texas, USA
| | - Jeesun Kim
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, Texas, USA
| | - Huan Zhang
- School of Life Science, University of Science and Technology of China, Hefei, China
| | - Caitlin J Murphy
- The University of Texas at Austin, College of Pharmacy, Austin, Texas, USA
| | - Tewfik Hamidi
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, Texas, USA
| | - Jean Jaubert
- Unité de Génétique de la Souris, Institut Pasteur, Paris, France
| | - Craig D Platt
- Division of Immunology, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Janet Chou
- Division of Immunology, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Meichun Deng
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Meng-Hua Zhou
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Yuying Huang
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Héctor Gaitán-Peñas
- Unitat de Fisiología, Departament de Ciències Fisiològiques, IDIBELL-Institute of Neurosciences, Universitat de Barcelona, L'Hospitalet de Llobregat, Spain.,U-750, CIBERER, ISCIII, Barcelona, Spain
| | | | - Kevin Lin
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, Texas, USA
| | - Yue Lu
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, Texas, USA
| | - Taiping Chen
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, Texas, USA.,UTHealth Graduate School of Biomedical Sciences, Houston, Texas, USA
| | - Mark T Bedford
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, Texas, USA.,UTHealth Graduate School of Biomedical Sciences, Houston, Texas, USA
| | - Sharon Yr Dent
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, Texas, USA.,UTHealth Graduate School of Biomedical Sciences, Houston, Texas, USA
| | - John H Richburg
- The University of Texas at Austin, College of Pharmacy, Austin, Texas, USA
| | - Raúl Estévez
- Unitat de Fisiología, Departament de Ciències Fisiològiques, IDIBELL-Institute of Neurosciences, Universitat de Barcelona, L'Hospitalet de Llobregat, Spain.,U-750, CIBERER, ISCIII, Barcelona, Spain
| | - Hui-Lin Pan
- Center for Neuroscience and Pain Research, Department of Anesthesiology and Perioperative Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Raif S Geha
- Division of Immunology, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Qinghua Shi
- School of Life Science, University of Science and Technology of China, Hefei, China
| | - Fernando Benavides
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, Texas, USA.,UTHealth Graduate School of Biomedical Sciences, Houston, Texas, USA
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Lück JC, Puchkov D, Ullrich F, Jentsch TJ. LRRC8/VRAC anion channels are required for late stages of spermatid development in mice. J Biol Chem 2018; 293:11796-11808. [PMID: 29880644 PMCID: PMC6066314 DOI: 10.1074/jbc.ra118.003853] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 05/31/2018] [Indexed: 11/06/2022] Open
Abstract
Spermatogenesis is a highly complex developmental process that occurs primarily in seminiferous tubules of the testes and requires additional maturation steps in the epididymis and beyond. Mutations in many different genes can lead to defective spermatozoa and hence to male infertility. Some of these genes encode for ion channels and transporters that play roles in various processes such as cellular ion homeostasis, signal transduction, sperm motility, and the acrosome reaction. Here we show that germ cell–specific, but not Sertoli cell–specific, disruption of Lrrc8a leads to abnormal sperm and male infertility in mice. LRRC8A (leucine-rich repeat containing 8A) is the only obligatory subunit of heteromeric volume-regulated anion channels (VRACs). Its ablation severely compromises cell volume regulation by completely abolishing the transport of anions and osmolytes through VRACs. Consistent with impaired volume regulation, the cytoplasm of late spermatids appeared swollen. These cells failed to properly reduce their cytoplasm during further development into spermatozoa and later displayed severely disorganized mitochondrial sheaths in the midpiece region, as well as angulated or coiled flagella. These changes, which progressed in severity on the way to the epididymis, resulted in dramatically reduced sperm motility. Our work shows that VRAC, probably through its role in cell volume regulation, is required in a cell-autonomous manner for proper sperm development and explains the male infertility of Lrrc8a−/− mice and the spontaneous mouse mutant ébouriffé.
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Affiliation(s)
- Jennifer C Lück
- From the Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), D-13125 Berlin, Germany.,the Max-Delbrück-Centrum für Molekulare Medizin (MDC), D-13125 Berlin, Germany.,the Graduate Program of the Freie Universität Berlin, 14195 Berlin, Germany, and
| | - Dmytro Puchkov
- From the Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), D-13125 Berlin, Germany
| | - Florian Ullrich
- From the Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), D-13125 Berlin, Germany.,the Max-Delbrück-Centrum für Molekulare Medizin (MDC), D-13125 Berlin, Germany
| | - Thomas J Jentsch
- From the Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), D-13125 Berlin, Germany, .,the Max-Delbrück-Centrum für Molekulare Medizin (MDC), D-13125 Berlin, Germany.,the Neurocure Cluster of Excellence, Charité Universitätsmedizin, 10117 Berlin, Germany
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Platt CD, Chou J, Houlihan P, Badran YR, Kumar L, Bainter W, Poliani PL, Perez CJ, Dent SYR, Clapham DE, Benavides F, Geha RS. Leucine-rich repeat containing 8A (LRRC8A)-dependent volume-regulated anion channel activity is dispensable for T-cell development and function. J Allergy Clin Immunol 2017; 140:1651-1659.e1. [PMID: 28192143 DOI: 10.1016/j.jaci.2016.12.974] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 11/20/2016] [Accepted: 12/12/2016] [Indexed: 10/20/2022]
Abstract
BACKGROUND Leucine-rich repeat containing 8A (LRRC8A) is an ubiquitously expressed transmembrane protein with 17 leucine-rich repeats (LRRs) at its C-terminal end and is an essential component of the volume-regulated anion channel (VRAC), which controls cellular volume. A heterozygous mutation in LRRC8A that truncates the 2 terminal LRRs was reported in a patient with agammaglobulinemia and absent B cells and was demonstrated to exert a dominant negative effect on T- and B-cell development in mice. Lrrc8a-/- mice have severely defective T-cell development and function. It is not known whether the T- and B-cell defects caused by LRRC8A deficiency are caused by loss of VRAC activity. OBJECTIVE We sought to determine whether VRAC activity is required for normal T-cell development and function. METHODS VRAC activity was examined by using patch-clamp analysis. Flow cytometry was used to examine T-cell development. T-cell proliferation, cytokine secretion, and antibody titers were measured by using standard techniques. RESULTS We demonstrate that the spontaneous mouse mutant ébouriffé (ebo/ebo) harbors a homozygous 2-bp frameshift mutation in Lrrc8a that truncates the 15 terminal LRRs of LRRC8A. The Lrrc8aebo mutation does not affect protein expression but drastically diminishes VRAC activity in T cells. ebo/ebo mice share features with Lrrc8a-/- mice that include curly hair, infertility, reduced longevity, and kidney abnormalities. However, in contrast to Lrrc8a-/- mice, ebo/ebo mice have normal T-cell development and function and intact antibody response to T-dependent antigen. CONCLUSION LRRC8A-dependent VRAC activity is dispensable for T-cell development and function.
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Affiliation(s)
- Craig D Platt
- Division of Immunology, Boston Children's Hospital, Harvard Medical School, Boston, Mass
| | - Janet Chou
- Division of Immunology, Boston Children's Hospital, Harvard Medical School, Boston, Mass
| | - Patrick Houlihan
- Department of Cardiology, Boston Children's Hospital, Boston, Mass
| | - Yousef R Badran
- Division of Immunology, Boston Children's Hospital, Harvard Medical School, Boston, Mass
| | - Lalit Kumar
- Division of Immunology, Boston Children's Hospital, Harvard Medical School, Boston, Mass
| | - Wayne Bainter
- Division of Immunology, Boston Children's Hospital, Harvard Medical School, Boston, Mass
| | - P Luigi Poliani
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Carlos J Perez
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas M. D. Anderson Cancer Center, Smithville, and the Graduate School of Biomedical Sciences at Houston, Houston, Tex
| | - Sharon Y R Dent
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas M. D. Anderson Cancer Center, Smithville, and the Graduate School of Biomedical Sciences at Houston, Houston, Tex
| | - David E Clapham
- Department of Cardiology, Boston Children's Hospital, Boston, Mass; Howard Hughes Medical Institute, Chevy Chase, Md
| | - Fernando Benavides
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas M. D. Anderson Cancer Center, Smithville, and the Graduate School of Biomedical Sciences at Houston, Houston, Tex
| | - Raif S Geha
- Division of Immunology, Boston Children's Hospital, Harvard Medical School, Boston, Mass.
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Segretain D, Gilleron J, Bacro JN, Di Marco M, Carette D, Pointis G. Ultrastructural localization and distribution of Nardilysin in mammalian male germ cells. Basic Clin Androl 2016; 26:5. [PMID: 27051521 PMCID: PMC4820967 DOI: 10.1186/s12610-016-0032-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 03/10/2016] [Indexed: 11/16/2022] Open
Abstract
Background NRD convertase, also termed Nardilysin, is a Zn++ metalloendopeptidase that specifically cleaves the N-terminus of arginine and lysine residues into dibasic moieties. Although this enzyme was found located within the testis, its function in male reproduction is largely unknown. In addition, the precise distribution of this enzyme within germ cells remains to be determined. Methods To answer these questions, we developed an immuno-gold electron microscopy analysis to detect Nardilysin at ultrastructural level in mice. In addition, we performed a quantitative analysis of these gold particles to statistically estimate the distribution of Nardilysin in the different subcellular compartments of differentiating late spermatids/spermatozoa. Results Expression of Nardilysin in wild-type mice was restricted to germ cells and markedly increased during the last steps of spermiogenesis. In elongated spermatids, we found the enzyme mainly localized in the cytoplasm, more precisely associated with two microtubular structures, the manchette and the axoneme. No labelling was detected over the membranous organelles of the spermatids. To test whether this localization is dependent of the functional microtubules organization of the flagella, we analysed the localization into a specific mouse mutant ebo/ebo (ébouriffé) known to be sterile due to an impairment of the final organization of the flagellum. In the ebo/ebo, the enzyme was still localized over the microtubules of the axoneme and over the isolated cytoplasmic microtubules doublets. Quantification of gold particles in wild-type and mutant flagella revealed the specific association of the enzyme within the microtubular area of the axoneme. Conclusions The strong and specific accumulation of Nardilysin in the manchette and axoneme suggests that the enzyme probably contributes either to the establishment of these specific microtubular structures and/or to their functional properties.
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Affiliation(s)
- D Segretain
- UMR S 1147 Université Paris Descartes, 45 rue des Saint-Pères, 75006 Paris, France ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Versailles, 78000 France
| | - J Gilleron
- INSERM U 1065, Université Nice Sophia-Antipolis, 151 route Saint-Antoine de Ginestière BP 2 3194, 06204, Nice, cedex 3 France
| | - J N Bacro
- Institut de Mathématiques et de Modélisation de Montpellier (I3M), UMR CNRS 5149 Université Montpellier, CC 51; 4 place Eugène Bataillon 34095, Montpellier, cedex 5 France
| | - M Di Marco
- UMR S 1147 Université Paris Descartes, 45 rue des Saint-Pères, 75006 Paris, France ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Versailles, 78000 France
| | - D Carette
- UMR S 1147 Université Paris Descartes, 45 rue des Saint-Pères, 75006 Paris, France ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Versailles, 78000 France
| | - G Pointis
- INSERM U 1065, Université Nice Sophia-Antipolis, 151 route Saint-Antoine de Ginestière BP 2 3194, 06204, Nice, cedex 3 France
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Maywood ES, Chahad-Ehlers S, Garabette ML, Pritchard C, Underhill P, Greenfield A, Ebling FJP, Kyriacou CP, Hastings MH, Reddy AB. Differential testicular gene expression in seasonal fertility. J Biol Rhythms 2009; 24:114-25. [PMID: 19346449 PMCID: PMC3398136 DOI: 10.1177/0748730409332029] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Spermatogenesis is an essential precursor for successful sexual reproduction. Recently, there has been an expansion in the knowledge of the genes associated with particular stages of normal, physiological testicular development and pubertal activation. What has been lacking, however, is an understanding of those genes that are involved in specifically regulating sperm production, rather than in maturation and elaboration of the testis as an organ. By using the reversible (seasonal) fertility of the Syrian hamster as a model system, the authors sought to discover genes that are specifically involved in turning off sperm production and not involved in tissue specification and/or maturation. Using gene expression microarrays and in situ hybridization in hamsters and genetically infertile mice, the authors have identified a variety of known and novel factors involved in reversible, transcriptional, translational, and posttranslational control of testicular function, as well those involved in cell division and macromolecular metabolism. The novel genes uncovered could be potential targets for therapies against fertility disorders.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Akhilesh B. Reddy
- MRC Laboratory of Molecular Biology, Cambridge
- Institute of Metabolic Science, University of Cambridge
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Gawlik V, Schmidt S, Scheepers A, Wennemuth G, Augustin R, Aumüller G, Moser M, Al-Hasani H, Kluge R, Joost HG, Schürmann A. Targeted disruption of Slc2a8 (GLUT8) reduces motility and mitochondrial potential of spermatozoa. Mol Membr Biol 2008; 25:224-35. [PMID: 18428038 PMCID: PMC2557070 DOI: 10.1080/09687680701855405] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
GLUT8 is a class 3 sugar transport facilitator which is predominantly expressed in testis and also detected in brain, heart, skeletal muscle, adipose tissue, adrenal gland, and liver. Since its physiological function in these tissues is unknown, we generated a Slc2a8 null mouse and characterized its phenotype. Slc2a8 knockout mice appeared healthy and exhibited normal growth, body weight development and glycemic control, indicating that GLUT8 does not play a significant role for maintenance of whole body glucose homeostasis. However, analysis of the offspring distribution of heterozygous mating indicated a lower number of Slc2a8 knockout offspring (30.5:47.3:22.1%, Slc2a8+/+, Slc2a8+/−, and Slc2a8−/− mice, respectively) resulting in a deviation (p = 0.0024) from the expected Mendelian distribution. This difference was associated with lower ATP levels, a reduced mitochondrial membrane potential and a significant reduction of sperm motility of the Slc2a8 knockout in comparison to wild-type spermatozoa. In contrast, number and survival rate of spermatozoa were not altered. These data indicate that GLUT8 plays an important role in the energy metabolism of sperm cells.
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Affiliation(s)
- Verena Gawlik
- Department of Pharmacology, German Institute of Human Nutrition Potsdam-Rehbruecke, Germany
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van der Spoel AC, Jeyakumar M, Butters TD, Charlton HM, Moore HD, Dwek RA, Platt FM. Reversible infertility in male mice after oral administration of alkylated imino sugars: a nonhormonal approach to male contraception. Proc Natl Acad Sci U S A 2002; 99:17173-8. [PMID: 12477936 PMCID: PMC139288 DOI: 10.1073/pnas.262586099] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
During mammalian spermatogenesis, male germ cells undergo a dramatic transformation, which includes a change of shape, nuclear condensation, and development of specialised structures, such as an acrosome, and a flagellum with a mitochondrial sheath. We have found a previously undescribed pharmacological approach to intervene in these events. After oral administration of the alkylated imino sugar N-butyldeoxynojirimycin (NB-DNJ) to mice, epididymal spermatozoa displayed a spectrum of abnormal head shapes, and acrosomal antigens were mostly absent or displayed irregular patterns. In addition, the mitochondria of these cells often had an aberrant morphology, and were arranged in relatively short and wide mitochondrial sheaths. The motility of the affected spermatozoa was severely impaired. After 3 weeks of administration of NB-DNJ, male mice became sterile, and regained their fertility during the fourth week off drug. The NB-DNJ-induced infertility was not associated with a reduction in the serum testosterone level. Biochemically, the capacity of imino sugars to impair spermatogenesis was associated with their potential to attenuate the biosynthesis of glucosylceramide-based sphingolipids. Our study reveals that male fertility is affected by partial glycosphingolipid depletion, or, alternatively, by a distinct as yet unidentified property that is shared by alkylated imino sugars that inhibit glucosylceramide biosynthesis. These compounds therefore may be new leads in the development of a male contraceptive, especially because NB-DNJ has already been through extensive evaluation in various mammals, including man.
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Affiliation(s)
- Aarnoud C van der Spoel
- The Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom
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Sato M, Ohta R, Kojima K, Shirota M. Strain differences in the spontaneous incidence of sperm morphological abnormalities in Hatano rats. J Vet Med Sci 2002; 64:389-90. [PMID: 12014589 DOI: 10.1292/jvms.64.389] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Two inbred strains of Hatano rats, which had been bred selectively on the basis for shuttlebox avoidance responses (high- and low-avoidance animals; HAA and LAA), were different in sperm motility. We have found that there are strain differences in the spontaneous incidence of sperm morphological abnormalities. The percentages of abnormalities were extraordinarily higher in the LAA rats, whose sperm motility was lesser. Since the high sperm abnormality was an exceptional case in rats, these rats may be useful models for sperm quality.
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Affiliation(s)
- Masako Sato
- Hatano Research Institute, Food and Drug Safety Center, Hadano, Kanagawa, Japan
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