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Schmauder R, Eick T, Schulz E, Sammler G, Voigt E, Mayer G, Ginter H, Ditze G, Benndorf K. Fast functional mapping of ligand-gated ion channels. Commun Biol 2023; 6:1003. [PMID: 37783870 PMCID: PMC10545696 DOI: 10.1038/s42003-023-05340-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 09/11/2023] [Indexed: 10/04/2023] Open
Abstract
Ligand-gated ion channels are formed by three to five subunits that control the opening of the pore in a cooperative fashion. We developed a microfluidic chip-based technique for studying ion currents and fluorescence signals in either excised membrane patches or whole cells to measure activation and deactivation kinetics of the channels as well as ligand binding and unbinding when using confocal patch-clamp fluorometry. We show how this approach produces in a few seconds either unidirectional concentration-activation relationships at or near equilibrium and, moreover, respective time courses of activation and deactivation for a large number of freely designed steps of the ligand concentration. The short measuring period strongly minimizes the contribution of disturbing superimposing effects such as run-down phenomena and desensitization effects. To validate gating mechanisms, complex kinetic schemes are quantified without the requirement to have data at equilibrium. The new method has potential for functionally analyzing any ligand-gated ion channel and, beyond, also for other receptors.
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Affiliation(s)
- Ralf Schmauder
- Institut für Physiologie II, Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, 07743, Jena, Germany.
| | - Thomas Eick
- Institut für Physiologie II, Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, 07743, Jena, Germany
| | - Eckhard Schulz
- Hochschule Schmalkalden, Fakultät Elektrotechnik, Blechhammer, 98574, Schmalkalden, Germany
| | - Günther Sammler
- Zentrale Forschungswerkstätten, Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, 07743, Jena, Germany
| | - Elmar Voigt
- Leibniz Institut für Photonische Technologien e.V., Albert-Einstein-Straße 9, 07745, Jena, Germany
| | - Günter Mayer
- Leibniz Institut für Photonische Technologien e.V., Albert-Einstein-Straße 9, 07745, Jena, Germany
| | - Holger Ginter
- Zentrale Forschungswerkstätten, Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, 07743, Jena, Germany
| | - Günter Ditze
- Zentrale Forschungswerkstätten, Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, 07743, Jena, Germany
| | - Klaus Benndorf
- Institut für Physiologie II, Universitätsklinikum Jena, Friedrich-Schiller-Universität Jena, 07743, Jena, Germany.
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2
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Cherninskyi A, Storozhuk M, Maximyuk O, Kulyk V, Krishtal O. Triggering of Major Brain Disorders by Protons and ATP: The Role of ASICs and P2X Receptors. Neurosci Bull 2023; 39:845-862. [PMID: 36445556 PMCID: PMC9707125 DOI: 10.1007/s12264-022-00986-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 08/14/2022] [Indexed: 11/30/2022] Open
Abstract
Adenosine triphosphate (ATP) is well-known as a universal source of energy in living cells. Less known is that this molecule has a variety of important signaling functions: it activates a variety of specific metabotropic (P2Y) and ionotropic (P2X) receptors in neuronal and non-neuronal cell membranes. So, a wide variety of signaling functions well fits the ubiquitous presence of ATP in the tissues. Even more ubiquitous are protons. Apart from the unspecific interaction of protons with any protein, many physiological processes are affected by protons acting on specific ionotropic receptors-acid-sensing ion channels (ASICs). Both protons (acidification) and ATP are locally elevated in various pathological states. Using these fundamentally important molecules as agonists, ASICs and P2X receptors signal a variety of major brain pathologies. Here we briefly outline the physiological roles of ASICs and P2X receptors, focusing on the brain pathologies involving these receptors.
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Affiliation(s)
- Andrii Cherninskyi
- Bogomoletz Institute of Physiology of National Academy of Sciences of Ukraine, Kyiv, 01024, Ukraine.
| | - Maksim Storozhuk
- Bogomoletz Institute of Physiology of National Academy of Sciences of Ukraine, Kyiv, 01024, Ukraine
| | - Oleksandr Maximyuk
- Bogomoletz Institute of Physiology of National Academy of Sciences of Ukraine, Kyiv, 01024, Ukraine
| | - Vyacheslav Kulyk
- Bogomoletz Institute of Physiology of National Academy of Sciences of Ukraine, Kyiv, 01024, Ukraine
| | - Oleg Krishtal
- Bogomoletz Institute of Physiology of National Academy of Sciences of Ukraine, Kyiv, 01024, Ukraine
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3
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Ion channel-related hereditary hearing loss: a narrative review. JOURNAL OF BIO-X RESEARCH 2021. [DOI: 10.1097/jbr.0000000000000108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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4
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Regulation of P2X1 receptors by modulators of the cAMP effectors PKA and EPAC. Proc Natl Acad Sci U S A 2021; 118:2108094118. [PMID: 34508006 DOI: 10.1073/pnas.2108094118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/12/2021] [Indexed: 11/18/2022] Open
Abstract
P2X1 receptors are adenosine triphosphate (ATP)-gated cation channels that are functionally important for male fertility, bladder contraction, and platelet aggregation. The activity of P2X1 receptors is modulated by lipids and intracellular messengers such as cAMP, which can stimulate protein kinase A (PKA). Exchange protein activated by cAMP (EPAC) is another cAMP effector; however, its effect on P2X1 receptors has not yet been determined. Here, we demonstrate that P2X1 currents, recorded from human embryonic kidney (HEK) cells transiently transfected with P2X1 cDNA, were inhibited by the highly selective EPAC activator 007-AM. In contrast, EPAC activation enhanced P2X2 current amplitude. The PKA activator 6-MB-cAMP did not affect P2X1 currents, but inhibited P2X2 currents. The inhibitory effects of EPAC on P2X1 were prevented by triple mutation of residues 21 to 23 on the amino terminus of P2X1 subunits to the equivalent amino acids on P2X2 receptors. Double mutation of residues 21 and 22 and single mutation of residue 23 also protected P2X1 receptors from inhibition by EPAC activation. Finally, the inhibitory effects of EPAC on P2X1 were also prevented by NSC23766, an inhibitor of Rac1, a member of the Rho family of small GTPases. These data suggest that EPAC is an important regulator of P2X1 and P2X2 receptors.
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5
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P2X7 receptor in multifaceted cellular signalling and its relevance as a potential therapeutic target in different diseases. Eur J Pharmacol 2021; 906:174235. [PMID: 34097884 DOI: 10.1016/j.ejphar.2021.174235] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 05/28/2021] [Accepted: 06/02/2021] [Indexed: 02/07/2023]
Abstract
P2X7 receptor, a purinergic receptor family member, is abundantly expressed on many cells, including immune, muscle, bone, neuron, and glia. It acts as an ATP-activated cation channel that permits the influx of Ca2+, Na+ and efflux of K+ ions. The P2X7 receptor plays crucial roles in many physiological processes including cytokine and chemokine secretion, NLRP3 inflammasome activation, cellular growth and differentiation, locomotion, wound healing, transcription factors activation, cell death and T-lymphocyte survival. Past studies have demonstrated the up-regulation and direct association of this receptor in many pathophysiological conditions such as cancer, diabetics, arthritis, tuberculosis (TB) and inflammatory diseases. Hence, targeting this receptor is considered a worthwhile approach to lessen the afflictions associated with the disorders mentioned above by understanding the receptor architecture and downstream signalling processes. Here, in the present review, we have dissected the structural and functional aspects of the P2X7 receptor, emphasizing its role in various diseased conditions. This information will provide in-depth knowledge about the receptor and help to develop apt curative methodologies for the betterment of humanity in the coming years.
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Peloggia J, Münch D, Meneses-Giles P, Romero-Carvajal A, Lush ME, Lawson ND, McClain M, Pan YA, Piotrowski T. Adaptive cell invasion maintains lateral line organ homeostasis in response to environmental changes. Dev Cell 2021; 56:1296-1312.e7. [PMID: 33878346 DOI: 10.1016/j.devcel.2021.03.027] [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: 11/25/2020] [Revised: 02/21/2021] [Accepted: 03/24/2021] [Indexed: 10/21/2022]
Abstract
Mammalian inner ear and fish lateral line sensory hair cells (HCs) detect fluid motion to transduce environmental signals. Actively maintained ionic homeostasis of the mammalian inner ear endolymph is essential for HC function. In contrast, fish lateral line HCs are exposed to the fluctuating ionic composition of the aqueous environment. Using lineage labeling, in vivo time-lapse imaging and scRNA-seq, we discovered highly motile skin-derived cells that invade mature mechanosensory organs of the zebrafish lateral line and differentiate into Neuromast-associated (Nm) ionocytes. This invasion is adaptive as it is triggered by environmental fluctuations. Our discovery of Nm ionocytes challenges the notion of an entirely placodally derived lateral line and identifies Nm ionocytes as likely regulators of HC function possibly by modulating the ionic microenvironment. Nm ionocytes provide an experimentally accessible in vivo system to study cell invasion and migration, as well as the physiological adaptation of vertebrate organs to changing environmental conditions.
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Affiliation(s)
- Julia Peloggia
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Daniela Münch
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | | | - Andrés Romero-Carvajal
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA; Pontificia Universidad Católica del Ecuador, Escuela de Ciencias Biológicas, Quito, Ecuador
| | - Mark E Lush
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Nathan D Lawson
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester 01605, USA
| | - Melainia McClain
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Y Albert Pan
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Tech, Roanoke, VA 24016, USA; Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24060, USA; Department of Psychiatry and Behavioral Medicine, Virginia Tech Carilion School of Medicine, Roanoke, VA 24016, USA
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7
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Chen X, Abad C, Chen ZY, Young JI, Gurumurthy CB, Walz K, Liu XZ. Generation and characterization of a P2rx2 V60L mouse model for DFNA41. Hum Mol Genet 2021; 30:985-995. [PMID: 33791800 DOI: 10.1093/hmg/ddab077] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 03/06/2021] [Accepted: 03/12/2021] [Indexed: 11/13/2022] Open
Abstract
P2RX2 encodes the P2X2 receptor, which is an adenosine triphosphate (ATP) gated (purinoreceptor) ion channel. P2RX2 c. 178G > T (p.V60L) mutation was previously identified in two unrelated Chinese families, as the cause of human DFNA41, a form of dominant, early-onset and progressive sensorineural hearing loss. We generated and characterized a knock-in mouse model based on human p.V60L mutation that recapitulates the human phenotype. Heterozygous KI mice started to exhibit hearing loss at 21-day-old and progressed to deafness by 6-month-old. Vestibular dysfunction was also observed in mutant mice. Abnormal morphology of the inner hair cells and ribbon synapses was progressively observed in KI animals suggesting that P2rx2 plays a role in the membrane spatial location of the ribbon synapses. These results suggest that P2rx2 is essential for acoustic information transfer, which can be the molecular mechanism related to hearing loss.
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Affiliation(s)
- Xiaoya Chen
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL 33136, USA.,Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Clemer Abad
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Zheng-Yi Chen
- Department of Otolaryngology and Program in Neuroscience, Harvard Medical School and Eaton Peabody Laboratory, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts 02114, USA
| | - Juan I Young
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL 33136, USA.,Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Channabasavaiah B Gurumurthy
- Mouse Genome Engineering Core Facility, Vice Chancellor for Research Office, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Katherina Walz
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL 33136, USA.,Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Xue Zhong Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL 33136, USA.,Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, FL 33136, USA
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Illes P, Müller CE, Jacobson KA, Grutter T, Nicke A, Fountain SJ, Kennedy C, Schmalzing G, Jarvis MF, Stojilkovic SS, King BF, Di Virgilio F. Update of P2X receptor properties and their pharmacology: IUPHAR Review 30. Br J Pharmacol 2020; 178:489-514. [PMID: 33125712 PMCID: PMC8199792 DOI: 10.1111/bph.15299] [Citation(s) in RCA: 162] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/20/2020] [Accepted: 10/22/2020] [Indexed: 12/20/2022] Open
Abstract
The known seven mammalian receptor subunits (P2X1–7) form cationic channels gated by ATP. Three subunits compose a receptor channel. Each subunit is a polypeptide consisting of two transmembrane regions (TM1 and TM2), intracellular N- and C-termini, and a bulky extracellular loop. Crystallization allowed the identification of the 3D structure and gating cycle of P2X receptors. The agonist-binding pocket is located at the intersection of two neighbouring subunits. In addition to the mammalian P2X receptors, their primitive ligand-gated counterparts with little structural similarity have also been cloned. Selective agonists for P2X receptor subtypes are not available, but medicinal chemistry supplied a range of subtype-selective antagonists, as well as positive and negative allosteric modulators. Knockout mice and selective antagonists helped to identify pathological functions due to defective P2X receptors, such as male infertility (P2X1), hearing loss (P2X2), pain/cough (P2X3), neuropathic pain (P2X4), inflammatory bone loss (P2X5), and faulty immune reactions (P2X7).
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Affiliation(s)
- Peter Illes
- Rudolf Boehm Institute for Pharmacology and Toxicology, University of Leipzig, Leipzig, Germany.,International Collaborative Centre on Big Science Plan for Purinergic Signalling, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Christa E Müller
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical & Medicinal Chemistry, University of Bonn, Bonn, Germany
| | - Kenneth A Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Thomas Grutter
- University of Strasbourg, Centre National de la Recherche Scientifique, CAMB UMR 7199, Strasbourg, France
| | - Annette Nicke
- Walther Straub Institute for Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, Munich, Germany
| | | | - Charles Kennedy
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK
| | - Günther Schmalzing
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
| | | | - Stanko S Stojilkovic
- Section on Cellular Signaling, The Eunice Kennedy Shiver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Brian F King
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK
| | - Francesco Di Virgilio
- Department of Medical Sciences, Section of Experimental Medicine, University of Ferrara, Ferrara, Italy
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Cochlear homeostasis: a molecular physiological perspective on maintenance of sound transduction and auditory neurotransmission with noise and ageing. CURRENT OPINION IN PHYSIOLOGY 2020. [DOI: 10.1016/j.cophys.2020.09.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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10
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Colangelo MT, Galli C, Guizzardi S. The effects of polydeoxyribonucleotide on wound healing and tissue regeneration: a systematic review of the literature. Regen Med 2020; 15:1801-1821. [PMID: 32757710 DOI: 10.2217/rme-2019-0118] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Aim: The present study evaluated the effects of polydeoxyribonucleotide (PDRN) on tissue regeneration, paying special attention to the molecular mechanisms that underlie its tissue remodeling actions to better identify its effective therapeutic potential in wound healing. Materials & methods: Strategic searches were conducted through MEDLINE/PubMed, Google Scholar, Scopus, Web of Science and the Cochrane Central Register of Controlled Trials, from their earliest available dates to March 2020. The studies were included with the following eligibility criteria: studies evaluating tissue regeneration, and being an in vitro, in vivo and clinical study. Results: Out of more than 90 articles, 34 fulfilled the eligibility criteria. All data obtained proved the ability of PDRN in promoting a physiological tissue repair through salvage pathway and adenosine A2A receptor activation. Conclusion: Up to date PDRN has proved promising results in term of wound regeneration, healing time and absence of side effects.
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Affiliation(s)
- Maria T Colangelo
- Department of Medicine & Surgery, Histology & Embryology Lab, University of Parma, Parma, Italy
| | - Carlo Galli
- Department of Medicine & Surgery, University of Parma, Parma, Italy
| | - Stefano Guizzardi
- Department of Medicine & Surgery, Histology & Embryology Lab, University of Parma, Parma, Italy
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Liu XZ, Yan D, Mittal R, Ballard ME, Feng Y. Progressive Dominant Hearing Loss (Autosomal Dominant Deafness-41) and P2RX2 Gene Mutations: A Phenotype-Genotype Study. Laryngoscope 2019; 130:1657-1663. [PMID: 31593348 DOI: 10.1002/lary.28318] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 05/29/2019] [Accepted: 08/28/2019] [Indexed: 01/14/2023]
Abstract
OBJECTIVES/HYPOTHESIS P2RX2 encoding P2X purinoreceptor 2 has been identified as the gene responsible for autosomal dominant deafness-41 (DFNA41) as well as mediating vulnerability to noise-induced hearing loss (NIHL). The objective of this study was to investigate the audiological and molecular characteristics of P2RX2-related deafness, with emphasis on its role in NIHL by determining the audiological characteristics of a previously reported six-generation DFNA41 family with a 10-year follow-up. We have also summarized phenotype-genotype correlations of P2RX2-related deafness in human and mouse models. STUDY DESIGN We describe clinical longitudinal follow-up in the DFNA41 family with P2RX2 (p.Val60Leu) mutation and perform a systematic literature search in PubMed and poster presentations on meeting/conference websites to identify current insights into P2RX2-mediated NIHL. METHODS Clinical and physical examinations of the family members were performed, and audiograms were obtained to assess the hearing thresholds. Clinical follow-up features in this DFNA41 family are presented along with correlation analyses of phenotype-genotype in all reported families with P2RX2-related deafness. RESULTS Progressive hearing impairment was confirmed by history and by audiological follow-up testing in all the patients. The onset of hearing loss was between age 25 and 35 years. All affected subjects had bilateral sensorineural hearing loss involving all frequencies with some significant gender differences. CONCLUSIONS Our study and the review of the literature suggest that P2RX2 plays a crucial role in predisposition to noise-induced and age-related hearing loss. A better knowledge about the P2RX2-associated genetic variants can help in developing novel therapeutic strategies. LEVEL OF EVIDENCE 2b Laryngoscope, 130:1657-1663, 2020.
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Affiliation(s)
- Xue Zhong Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida, U.S.A.,Dr. John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genetics, University of Miami Miller School of Medicine, Miami, Florida, U.S.A
| | - Denise Yan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida, U.S.A
| | - Rahul Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida, U.S.A
| | - Megan E Ballard
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida, U.S.A
| | - Yong Feng
- Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, China
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Dong Y, Peng T, Wu W, Tan D, Liu X, Xie D. Efficient introduction of an isogenic homozygous mutation to induced pluripotent stem cells from a hereditary hearing loss family using CRISPR/Cas9 and single-stranded donor oligonucleotides. J Int Med Res 2019; 47:1717-1730. [PMID: 30819013 PMCID: PMC6460615 DOI: 10.1177/0300060519829990] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 01/17/2019] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Heterozygous purinergic receptor p2x gene ( P2RX2) c.178G>T (p.V60L) mutations can lead to progressive hearing loss (HL) and increased susceptibility to noise. However, the underlying mechanisms remain unclear. A combination of human induced pluripotent stem cell (hiPSC) technology with clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR-associated protein (Cas)9-mediated gene editing may provide a promising tool to study gene function and treat hereditary deafness in humans. METHODS hiPSC technology and CRISPR/Cas9-mediated gene editing were used to generate heterozygous and homozygous P2RX2 c.178G>T (p.V60L) cell models. RESULTS We generated non-integrative hiPSCs from urine samples derived from three members of a large Chinese family carrying heterozygous P2RX2 c.178G>T mutations (designated P2RX2+/-) as a model to study P2RX2-mediated hereditary HL. Furthermore, we used CRISPR/Cas9 and single-stranded donor oligonucleotides to genetically establish homozygous P2RX2 c.178G>T hiPSCs (designated P2RX2-/-) from heterozygous patient-specific hiPSCs as a control to further study the pathological gene function. CONCLUSIONS Heterozygous and homozygous P2RX2-mutated hiPSC lines are good models to investigate the pathological mechanisms of P2RX2 mutations in HL pathogenesis. Our findings confirmed our hypothesis that it is feasible and convenient to introduce precise point mutations into genomic loci of interest to generate gene-mutated hiPSC models.
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Affiliation(s)
- Yunpeng Dong
- Department of Otolaryngology Head and Neck Surgery, Institute of Otology, the Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- Departments of Otolaryngology and Head and Neck Surgery, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA
| | - Tao Peng
- Department of Otolaryngology Head and Neck Surgery, Institute of Otology, the Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Weijing Wu
- Department of Otolaryngology Head and Neck Surgery, Institute of Otology, the Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Donghui Tan
- Department of Otolaryngology Head and Neck Surgery, the Affiliated Hospital of Xiangnan College, Chenzhou, Hunan, China
| | - Xuezhong Liu
- Department of Otolaryngology Head and Neck Surgery, Institute of Otology, the Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- Departments of Otolaryngology and Head and Neck Surgery, University of Miami Leonard M. Miller School of Medicine, Miami, Florida, USA
| | - Dinghua Xie
- Department of Otolaryngology Head and Neck Surgery, Institute of Otology, the Second Xiangya Hospital, Central South University, Changsha, Hunan, China
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Eshraghi AA, Jung HD, Mittal R. Recent Advancements in Gene and Stem Cell-Based Treatment Modalities: Potential Implications in Noise-Induced Hearing Loss. Anat Rec (Hoboken) 2019; 303:516-526. [PMID: 30859735 DOI: 10.1002/ar.24107] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 06/24/2018] [Accepted: 08/23/2018] [Indexed: 12/13/2022]
Abstract
Noise-induced hearing loss (NIHL) poses a significant burden on not only the economics of health care but also the quality of life of an individual, as we approach an unprecedented age of longevity. In this article, we will delineate the current landscape of management of NIHL. We discuss the most recent results from in vitro and in vivo studies that determine the effectiveness of established pharmacotherapy such as corticosteroid and potential emerging therapies like N-acetyl cysteine and neurotrophins (NTs), as well as highlight ongoing clinical trials for these therapeutic agents. We present an overview of how the recent advancements in the field of gene-based and stem cell-based therapies can help in developing effective therapeutic strategies for NIHL. Gene-based therapies have shown exciting results demonstrating cochlear cellular regeneration using Atoh1, NRF2 as well as NT gene therapy employing viral vectors. In addition, we will discuss the recent advancements in genome-editing technologies, such as CRISPR/Cas9, and its potential role in NIHL therapy. We will further discuss the current state of stem cell therapy as it pertains to treating neurodegenerative conditions including NIHL. Embryonic stem cells, adult-derived stem cells, and induced pluripotent stem cells all represent an enticing reservoir of replacing damaged cells as a result of NIHL. Finally, we will discuss the barriers that need to be overcome to translate these promising treatment modalities to the clinical practice in pursuit of improving quality of life of patients having NIHL. Anat Rec, 303:516-526, 2020. © 2019 American Association for Anatomy.
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Affiliation(s)
- Adrien A Eshraghi
- Department of Otolaryngology, Hearing Research Laboratory, University of Miami Miller School of Medicine, Miami, Florida
| | - Hyunseo D Jung
- Department of Otolaryngology, Hearing Research Laboratory, University of Miami Miller School of Medicine, Miami, Florida
| | - Rahul Mittal
- Department of Otolaryngology, Hearing Research Laboratory, University of Miami Miller School of Medicine, Miami, Florida
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14
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The therapeutic potential of purinergic signalling. Biochem Pharmacol 2018; 151:157-165. [DOI: 10.1016/j.bcp.2017.07.016] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 07/18/2017] [Indexed: 01/05/2023]
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15
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Burnstock G. Purinergic Signalling: Therapeutic Developments. Front Pharmacol 2017; 8:661. [PMID: 28993732 PMCID: PMC5622197 DOI: 10.3389/fphar.2017.00661] [Citation(s) in RCA: 263] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 09/05/2017] [Indexed: 12/15/2022] Open
Abstract
Purinergic signalling, i.e., the role of nucleotides as extracellular signalling molecules, was proposed in 1972. However, this concept was not well accepted until the early 1990's when receptor subtypes for purines and pyrimidines were cloned and characterised, which includes four subtypes of the P1 (adenosine) receptor, seven subtypes of P2X ion channel receptors and 8 subtypes of the P2Y G protein-coupled receptor. Early studies were largely concerned with the physiology, pharmacology and biochemistry of purinergic signalling. More recently, the focus has been on the pathophysiology and therapeutic potential. There was early recognition of the use of P1 receptor agonists for the treatment of supraventricular tachycardia and A2A receptor antagonists are promising for the treatment of Parkinson's disease. Clopidogrel, a P2Y12 antagonist, is widely used for the treatment of thrombosis and stroke, blocking P2Y12 receptor-mediated platelet aggregation. Diquafosol, a long acting P2Y2 receptor agonist, is being used for the treatment of dry eye. P2X3 receptor antagonists have been developed that are orally bioavailable and stable in vivo and are currently in clinical trials for the treatment of chronic cough, bladder incontinence, visceral pain and hypertension. Antagonists to P2X7 receptors are being investigated for the treatment of inflammatory disorders, including neurodegenerative diseases. Other investigations are in progress for the use of purinergic agents for the treatment of osteoporosis, myocardial infarction, irritable bowel syndrome, epilepsy, atherosclerosis, depression, autism, diabetes, and cancer.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical SchoolLondon, United Kingdom
- Department of Pharmacology and Therapeutics, The University of Melbourne, MelbourneVIC, Australia
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Mittal R, Nguyen D, Patel AP, Debs LH, Mittal J, Yan D, Eshraghi AA, Van De Water TR, Liu XZ. Recent Advancements in the Regeneration of Auditory Hair Cells and Hearing Restoration. Front Mol Neurosci 2017; 10:236. [PMID: 28824370 PMCID: PMC5534485 DOI: 10.3389/fnmol.2017.00236] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 07/11/2017] [Indexed: 12/18/2022] Open
Abstract
Neurosensory responses of hearing and balance are mediated by receptors in specialized neuroepithelial sensory cells. Any disruption of the biochemical and molecular pathways that facilitate these responses can result in severe deficits, including hearing loss and vestibular dysfunction. Hearing is affected by both environmental and genetic factors, with impairment of auditory function being the most common neurosensory disorder affecting 1 in 500 newborns, as well as having an impact on the majority of elderly population. Damage to auditory sensory cells is not reversible, and if sufficient damage and cell death have taken place, the resultant deficit may lead to permanent deafness. Cochlear implants are considered to be one of the most successful and consistent treatments for deaf patients, but only offer limited recovery at the expense of loss of residual hearing. Recently there has been an increased interest in the auditory research community to explore the regeneration of mammalian auditory hair cells and restoration of their function. In this review article, we examine a variety of recent therapies, including genetic, stem cell and molecular therapies as well as discussing progress being made in genome editing strategies as applied to the restoration of hearing function.
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Affiliation(s)
- Rahul Mittal
- Department of Otolaryngology, University of Miami Miller School of MedicineMiami, FL, United States
| | - Desiree Nguyen
- Department of Otolaryngology, University of Miami Miller School of MedicineMiami, FL, United States
| | - Amit P. Patel
- Department of Otolaryngology, University of Miami Miller School of MedicineMiami, FL, United States
| | - Luca H. Debs
- Department of Otolaryngology, University of Miami Miller School of MedicineMiami, FL, United States
| | - Jeenu Mittal
- Department of Otolaryngology, University of Miami Miller School of MedicineMiami, FL, United States
| | - Denise Yan
- Department of Otolaryngology, University of Miami Miller School of MedicineMiami, FL, United States
| | - Adrien A. Eshraghi
- Department of Otolaryngology, University of Miami Miller School of MedicineMiami, FL, United States
| | - Thomas R. Van De Water
- Department of Otolaryngology, University of Miami Miller School of MedicineMiami, FL, United States
| | - Xue Z. Liu
- Department of Otolaryngology, University of Miami Miller School of MedicineMiami, FL, United States
- Department of Otolaryngology, Xiangya Hospital, Central South UniversityChangsha, China
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Mittal R, Debs LH, Nguyen D, Patel AP, Grati M, Mittal J, Yan D, Eshraghi AA, Liu XZ. Signaling in the Auditory System: Implications in Hair Cell Regeneration and Hearing Function. J Cell Physiol 2017; 232:2710-2721. [DOI: 10.1002/jcp.25695] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 11/18/2016] [Indexed: 02/06/2023]
Affiliation(s)
- Rahul Mittal
- Department of Otolaryngology; University of Miami Miller School of Medicine; Miami Florida
| | - Luca H. Debs
- Department of Otolaryngology; University of Miami Miller School of Medicine; Miami Florida
| | - Desiree Nguyen
- Department of Otolaryngology; University of Miami Miller School of Medicine; Miami Florida
| | - Amit P. Patel
- Department of Otolaryngology; University of Miami Miller School of Medicine; Miami Florida
| | - M'hamed Grati
- Department of Otolaryngology; University of Miami Miller School of Medicine; Miami Florida
| | - Jeenu Mittal
- Department of Otolaryngology; University of Miami Miller School of Medicine; Miami Florida
| | - Denise Yan
- Department of Otolaryngology; University of Miami Miller School of Medicine; Miami Florida
| | - Adrien A. Eshraghi
- Department of Otolaryngology; University of Miami Miller School of Medicine; Miami Florida
| | - Xue Zhong Liu
- Department of Otolaryngology; University of Miami Miller School of Medicine; Miami Florida
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18
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Mittal R, Grati M, Sedlacek M, Yuan F, Chang Q, Yan D, Lin X, Kachar B, Farooq A, Chapagain P, Zhang Y, Liu XZ. Characterization of ATPase Activity of P2RX2 Cation Channel. Front Physiol 2016; 7:186. [PMID: 27252659 PMCID: PMC4878533 DOI: 10.3389/fphys.2016.00186] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 05/09/2016] [Indexed: 12/31/2022] Open
Abstract
P2X purinergic receptors are plasma membrane ATP-dependent cation channels that are broadly distributed in the mammalian tissues. P2RX2 is a modulator of auditory sensory hair cell mechanotransduction and plays an important role in hair cell tolerance to noise. In this study, we demonstrate for the first time in vitro and in cochlear neuroepithelium, that P2RX2 possesses the ATPase activity. We observed that the P2RX2 V60L human deafness mutation alters its ability to bind ATP, while the G353R has no effect on ATP binding or hydrolysis. A non-hydrolysable ATP assay using HEK293 cells suggests that ATP hydrolysis plays a significant role in the opening and gating of the P2RX2 ion channel. Moreover, the results of structural modeling of the molecule was in agreement with our experimental observations. These novel findings suggest the intrinsic ATPase activity of P2RX2 and provide molecular insights into the channel opening.
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Affiliation(s)
- Rahul Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine Miami, FL, USA
| | - M'hamed Grati
- Department of Otolaryngology, University of Miami Miller School of Medicine Miami, FL, USA
| | - Miloslav Sedlacek
- Laboratory of Cell Structure and Dynamics, Section on Structural Cell Biology, National Institute on Deafness and Other Communication Disorders, National Institutes of Health Bethesda, MD, USA
| | - Fenghua Yuan
- Department of Biochemistry, University of Miami Leonard M. Miller School of Medicine Miami, FL, USA
| | - Qing Chang
- Department of Otolaryngology, Emory University Atlanta, GA, USA
| | - Denise Yan
- Department of Otolaryngology, University of Miami Miller School of Medicine Miami, FL, USA
| | - Xi Lin
- Department of Otolaryngology, Emory University Atlanta, GA, USA
| | - Bechara Kachar
- Laboratory of Cell Structure and Dynamics, Section on Structural Cell Biology, National Institute on Deafness and Other Communication Disorders, National Institutes of Health Bethesda, MD, USA
| | - Amjad Farooq
- Department of Biochemistry, University of Miami Leonard M. Miller School of Medicine Miami, FL, USA
| | - Prem Chapagain
- Department of Physics, Florida International University Miami, FL, USA
| | - Yanbin Zhang
- Department of Biochemistry, University of Miami Leonard M. Miller School of Medicine Miami, FL, USA
| | - Xue Z Liu
- Department of Otolaryngology, University of Miami Miller School of MedicineMiami, FL, USA; Department of Biochemistry, University of Miami Leonard M. Miller School of MedicineMiami, FL, USA; Department of Otolaryngology, Central South University, Xiangya HospitalChangsha, China
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