1
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Centonze E, Kellenberger S. Voltage-clamp fluorometry for advancing mechanistic understanding of ion channel mechanisms with a focus on acid-sensing ion channels. Biochem Soc Trans 2024:BST20240165. [PMID: 39400205 DOI: 10.1042/bst20240165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2024] [Revised: 09/13/2024] [Accepted: 09/20/2024] [Indexed: 10/15/2024]
Abstract
Voltage-clamp fluorometry (VCF) has revolutionized the study of ion channels by combining electrophysiology with fluorescence spectroscopy. VCF allows ion channel researchers to link dynamic structural changes, measured in real time, to function. Acid-sensing ion channels (ASICs) are Na+-permeable non-voltage-gated ion channels of the central and peripheral nervous system. They function as pH sensors, triggering neuronal excitation when pH decreases. Animal studies have shown the importance of ASICs for pain and fear sensation, learning, and neurodegeneration following ischaemic stroke. This review explores the technical bases and various developments of VCF, including fluorescence resonance energy transfer and the use of unnatural fluorescent amino acids. We provide an overview of VCF applications with a focus on ASICs, detailing how VCF has unveiled proton-induced conformational changes in key regions such as the acid pocket, wrist, and pore, crucial for understanding transitions between closed, open, and desensitized states.
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Affiliation(s)
- Eleonora Centonze
- Department of Biomedical Sciences, University of Lausanne, 1011 Lausanne, Switzerland
| | - Stephan Kellenberger
- Department of Biomedical Sciences, University of Lausanne, 1011 Lausanne, Switzerland
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2
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Holm CM, Topaktas AB, Dannesboe J, Pless SA, Heusser SA. Dynamic conformational changes of acid-sensing ion channels in different desensitizing conditions. Biophys J 2024; 123:2122-2135. [PMID: 38549370 PMCID: PMC11309988 DOI: 10.1016/j.bpj.2024.03.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 02/21/2024] [Accepted: 03/26/2024] [Indexed: 04/18/2024] Open
Abstract
Acid-sensing ion channels (ASICs) are proton-gated cation channels that contribute to fast synaptic transmission and have roles in fear conditioning and nociception. Apart from activation at low pH, ASIC1a also undergoes several types of desensitization, including acute desensitization, which terminates activation; steady-state desensitization, which occurs at sub-activating proton concentrations and limits subsequent activation; and tachyphylaxis, which results in a progressive decrease in response during a series of activations. Structural insights from a desensitized state of ASIC1 have provided great spatial detail, but dynamic insights into conformational changes in different desensitizing conditions are largely missing. Here, we use electrophysiology and voltage-clamp fluorometry to follow the functional changes of the pore along with conformational changes at several positions in the extracellular and upper transmembrane domain via cysteine-labeled fluorophores. Acute desensitization terminates activation in wild type, but introducing an N414K mutation in the β11-12 linker of mouse ASIC1a interfered with this process. The mutation also affected steady-state desensitization and led to pronounced tachyphylaxis. Although the extracellular domain of this mutant remained sensitive to pH and underwent pH-dependent conformational changes, these conformational changes did not necessarily lead to desensitization. N414K-containing channels also remained sensitive to a known peptide modulator that increases steady-state desensitization, indicating that the mutation only reduced, but not precluded, desensitization. Together, this study contributes to our understanding of the fundamental properties of ASIC1a desensitization, emphasizing the complex interplay between the conformational changes of the extracellular domain and the pore during channel activation and desensitization.
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Affiliation(s)
- Caroline Marcher Holm
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Asli B Topaktas
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark; Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Johs Dannesboe
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark; Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Stephan A Pless
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Stephanie A Heusser
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark.
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3
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Haug FM, Pumroy RA, Sridhar A, Pantke S, Dimek F, Fricke TC, Hage A, Herzog C, Echtermeyer FG, de la Roche J, Koh A, Kotecha A, Howard RJ, Lindahl E, Moiseenkova-Bell V, Leffler A. Functional and structural insights into activation of TRPV2 by weak acids. EMBO J 2024; 43:2264-2290. [PMID: 38671253 PMCID: PMC11148119 DOI: 10.1038/s44318-024-00106-4] [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: 10/02/2023] [Revised: 03/25/2024] [Accepted: 03/27/2024] [Indexed: 04/28/2024] Open
Abstract
Transient receptor potential (TRP) ion channels are involved in the surveillance or regulation of the acid-base balance. Here, we demonstrate that weak carbonic acids, including acetic acid, lactic acid, and CO2 activate and sensitize TRPV2 through a mechanism requiring permeation through the cell membrane. TRPV2 channels in cell-free inside-out patches maintain weak acid-sensitivity, but protons applied on either side of the membrane do not induce channel activation or sensitization. The involvement of proton modulation sites for weak acid-sensitivity was supported by the identification of titratable extracellular (Glu495, Glu561) and intracellular (His521) residues on a cryo-EM structure of rat TRPV2 (rTRPV2) treated with acetic acid. Molecular dynamics simulations as well as patch clamp experiments on mutant rTRPV2 constructs confirmed that these residues are critical for weak acid-sensitivity. We also demonstrate that the pore residue Glu609 dictates an inhibition of weak acid-induced currents by extracellular calcium. Finally, TRPV2-expression in HEK293 cells is associated with an increased weak acid-induced cytotoxicity. Together, our data provide new insights into weak acids as endogenous modulators of TRPV2.
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Affiliation(s)
- Ferdinand M Haug
- Department of Anesthesiology and Intensive Care Medicine, Hannover Medical School, 30625, Hannover, Germany
| | - Ruth A Pumroy
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA
| | - Akshay Sridhar
- Department of Applied Physics, Science for Life Laboratory, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Sebastian Pantke
- Department of Anesthesiology and Intensive Care Medicine, Hannover Medical School, 30625, Hannover, Germany
| | - Florian Dimek
- Department of Anesthesiology and Intensive Care Medicine, Hannover Medical School, 30625, Hannover, Germany
| | - Tabea C Fricke
- Department of Anesthesiology and Intensive Care Medicine, Hannover Medical School, 30625, Hannover, Germany
| | - Axel Hage
- Department of Anesthesiology and Intensive Care Medicine, Hannover Medical School, 30625, Hannover, Germany
| | - Christine Herzog
- Department of Anesthesiology and Intensive Care Medicine, Hannover Medical School, 30625, Hannover, Germany
| | - Frank G Echtermeyer
- Department of Anesthesiology and Intensive Care Medicine, Hannover Medical School, 30625, Hannover, Germany
| | - Jeanne de la Roche
- Institute for Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Adrian Koh
- Thermo Fisher Scientific, Eindhoven, The Netherlands
| | - Abhay Kotecha
- Thermo Fisher Scientific, Eindhoven, The Netherlands
| | - Rebecca J Howard
- Department of Biochemistry and Biophysics, Science for Life Laboratory, Stockholm University, Stockholm, Sweden
| | - Erik Lindahl
- Department of Applied Physics, Science for Life Laboratory, KTH Royal Institute of Technology, Stockholm, Sweden
- Department of Biochemistry and Biophysics, Science for Life Laboratory, Stockholm University, Stockholm, Sweden
| | - Vera Moiseenkova-Bell
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA.
| | - Andreas Leffler
- Department of Anesthesiology and Intensive Care Medicine, Hannover Medical School, 30625, Hannover, Germany.
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4
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Sun H, Yang T, Simon R, Xiong ZG, Leng T. Cholestane-3β,5α,6β-Triol Inhibits Acid-Sensing Ion Channels and Reduces Acidosis-Mediated Ischemic Brain Injury. Stroke 2024; 55:1660-1671. [PMID: 38660789 PMCID: PMC11126354 DOI: 10.1161/strokeaha.124.046963] [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: 01/11/2024] [Accepted: 03/25/2024] [Indexed: 04/26/2024]
Abstract
BACKGROUND Activation of the acid-sensing ion channels (ASICs) by tissue acidosis, a common feature of brain ischemia, contributes to ischemic brain injury, while blockade of ASICs results in protection. Cholestane-3β,5α,6β-triol (Triol), a major cholesterol metabolite, has been demonstrated as an endogenous neuroprotectant; however, the mechanism underlying its neuroprotective activity remains elusive. In this study, we tested the hypothesis that inhibition of ASICs is a potential mechanism. METHODS The whole-cell patch-clamp technique was used to examine the effect of Triol on ASICs heterogeneously expressed in Chinese hamster ovary cells and ASICs endogenously expressed in primary cultured mouse cortical neurons. Acid-induced injury of cultured mouse cortical neurons and middle cerebral artery occlusion-induced ischemic brain injury in wild-type and ASIC1 and ASIC2 knockout mice were studied to examine the protective effect of Triol. RESULTS Triol inhibits ASICs in a subunit-dependent manner. In Chinese hamster ovary cells, it inhibits homomeric ASIC1a and ASIC3 without affecting ASIC1β and ASIC2a. In cultured mouse cortical neurons, it inhibits homomeric ASIC1a and heteromeric ASIC1a-containing channels. The inhibition is use-dependent but voltage- and pH-independent. Structure-activity relationship analysis suggests that hydroxyls at the 5 and 6 positions of the A/B ring are critical functional groups. Triol alleviates acidosis-mediated injury of cultured mouse cortical neurons and protects against middle cerebral artery occlusion-induced brain injury in an ASIC1a-dependent manner. CONCLUSIONS Our study identifies Triol as a novel ASIC inhibitor, which may serve as a new pharmacological tool for studying ASICs and may also be developed as a potential drug for treating stroke.
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Affiliation(s)
- Huawei Sun
- Department of Neurobiology, Morehouse School of Medicine, 720 Westview Dr. SW, Atlanta, GA 30329, USA
| | - Tao Yang
- Department of Neurobiology, Morehouse School of Medicine, 720 Westview Dr. SW, Atlanta, GA 30329, USA
| | - Roger Simon
- Department of Neurobiology, Morehouse School of Medicine, 720 Westview Dr. SW, Atlanta, GA 30329, USA
| | - Zhi-gang Xiong
- Department of Neurobiology, Morehouse School of Medicine, 720 Westview Dr. SW, Atlanta, GA 30329, USA
| | - Tiandong Leng
- Department of Neurobiology, Morehouse School of Medicine, 720 Westview Dr. SW, Atlanta, GA 30329, USA
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5
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Pissas KP, Schilling M, Tian Y, Gründer S. Functional characterization of acid-sensing ion channels in the cerebellum-originating medulloblastoma cell line DAOY and in cerebellar granule neurons. Pflugers Arch 2023; 475:1073-1087. [PMID: 37474775 PMCID: PMC10409673 DOI: 10.1007/s00424-023-02839-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 07/03/2023] [Accepted: 07/09/2023] [Indexed: 07/22/2023]
Abstract
Acid-sensing ion channels (ASICs) are Na+ channels that are almost ubiquitously expressed in neurons of the brain. Functional ASIC1a is also expressed in glioblastoma stem cells, where it might sense the acidic tumor microenvironment. Prolonged acidosis induces cell death in neurons and reduces tumor sphere formation in glioblastoma via activation of ASIC1a. It is currently unknown whether ASICs are expressed and involved in acid-induced cell death in other types of brain tumors. In this study, we investigated ASICs in medulloblastoma, using two established cell lines, DAOY and UW228, as in vitro models. In addition, we characterized ASICs in the most numerous neuron of the brain, the cerebellar granule cell, which shares the progenitor cell with some forms of medulloblastoma. We report compelling evidence using RT-qPCR, western blot and whole-cell patch clamp that DAOY and cerebellar granule cells, but not UW228 cells, functionally express homomeric ASIC1a. Additionally, Ca2+-imaging revealed that extracellular acidification elevated intracellular Ca2+-levels in DAOY cells independently of ASICs. Finally, we show that overexpression of RIPK3, a key component of the necroptosis pathway, renders DAOY cells susceptible to acid-induced cell death via activation of ASIC1a. Our data support the idea that ASIC1a is an important acid sensor in brain tumors and that its activation has potential to induce cell death in tumor cells.
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Affiliation(s)
| | - Maria Schilling
- Institute of Physiology, RWTH Aachen University, Pauwelsstraße 30, 52074, Aachen, Germany
| | - Yuemin Tian
- Institute of Physiology, RWTH Aachen University, Pauwelsstraße 30, 52074, Aachen, Germany
| | - Stefan Gründer
- Institute of Physiology, RWTH Aachen University, Pauwelsstraße 30, 52074, Aachen, Germany.
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6
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Fischer L, Schmidt A, Dopychai A, Joussen S, Joeres N, Oslender-Bujotzek A, Schmalzing G, Gründer S. Physiologically relevant acid-sensing ion channel (ASIC) 2a/3 heteromers have a 1:2 stoichiometry. Commun Biol 2023; 6:701. [PMID: 37422581 PMCID: PMC10329638 DOI: 10.1038/s42003-023-05087-4] [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: 09/12/2022] [Accepted: 06/29/2023] [Indexed: 07/10/2023] Open
Abstract
Acid-sensing ion channels (ASICs) sense extracellular protons and are involved in synaptic transmission and pain sensation. ASIC1a and ASIC3 are the ASIC subunits with the highest proton sensitivity. ASIC2a in contrast has low proton sensitivity but increases the variability of ASICs by forming heteromers with ASIC1a or ASIC3. ASICs are trimers and for the ASIC1a/2a heteromer it has been shown that subunits randomly assemble with a flexible 1:2/2:1 stoichiometry. Both heteromers have almost identical proton sensitivity intermediate between ASIC1a and ASIC2a. Here, we investigated the stoichiometry of the ASIC2a/3 heteromer. Using electrophysiology, we extensively characterized, first, cells expressing ASIC2a and ASIC3 at different ratios, second, concatemeric channels with a fixed subunit stoichiometry, and, third, channels containing loss-of-functions mutations in specific subunits. Our results conclusively show that only ASIC2a/3 heteromers with a 1:2 stoichiometry had a proton-sensitivity intermediate between ASIC2a and ASIC3. In contrast, the proton sensitivity of ASIC2a/3 heteromers with a 2:1 stoichiometry was strongly acid-shifted by more than one pH unit, which suggests that they are not physiologically relevant. Together, our results reveal that the proton sensitivity of the two ASIC2a/3 heteromers is clearly different and that ASIC3 and ASIC1a make remarkably different contributions to heteromers with ASIC2a.
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Affiliation(s)
- Leon Fischer
- Institute of Physiology, RWTH Aachen University, Pauwelsstrasse 30, D-52074, Aachen, Germany
- Department of Anesthesiology, Technical University Dresden, Dresden, Germany
| | - Axel Schmidt
- Institute of Physiology, RWTH Aachen University, Pauwelsstrasse 30, D-52074, Aachen, Germany
- Institute of Human Genetics, University of Bonn, School of Medicine & University Hospital Bonn, Bonn, Germany
| | - Anke Dopychai
- Institute of Clinical Pharmacology, RWTH Aachen University, Wendlingweg, D-52074, Aachen, Germany
| | - Sylvia Joussen
- Institute of Physiology, RWTH Aachen University, Pauwelsstrasse 30, D-52074, Aachen, Germany
| | - Niko Joeres
- Institute of Physiology, RWTH Aachen University, Pauwelsstrasse 30, D-52074, Aachen, Germany
- Department of Nephrology and Clinical Immunology, RWTH Aachen University, Pauwelsstrasse 30, D-52074, Aachen, Germany
| | | | - Günther Schmalzing
- Institute of Clinical Pharmacology, RWTH Aachen University, Wendlingweg, D-52074, Aachen, Germany
| | - Stefan Gründer
- Institute of Physiology, RWTH Aachen University, Pauwelsstrasse 30, D-52074, Aachen, Germany.
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7
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Ge H, Zhou T, Zhang C, Cun Y, Chen W, Yang Y, Zhang Q, Li H, Zhong J, Zhang X, Feng H, Hu R. Targeting ASIC1a Promotes Neural Progenitor Cell Migration and Neurogenesis in Ischemic Stroke. RESEARCH (WASHINGTON, D.C.) 2023; 6:0105. [PMID: 37275123 PMCID: PMC10234266 DOI: 10.34133/research.0105] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 03/13/2023] [Indexed: 06/07/2023]
Abstract
Cell replacement therapy using neural progenitor cells (NPCs) has been shown to be an effective treatment for ischemic stroke. However, the therapeutic effect is unsatisfactory due to the imbalanced homeostasis of the local microenvironment after ischemia. Microenvironmental acidosis is a common imbalanced homeostasis in the penumbra and could activate acid-sensing ion channels 1a (ASIC1a), a subunit of proton-gated cation channels following ischemic stroke. However, the role of ASIC1a in NPCs post-ischemia remains elusive. Here, our results indicated that ASIC1a was expressed in NPCs with channel functionality, which could be activated by extracellular acidification. Further evidence revealed that ASIC1a activation inhibited NPC migration and neurogenesis through RhoA signaling-mediated reorganization of filopodia formation, which could be primarily reversed by pharmacological or genetic disruption of ASIC1a. In vivo data showed that the knockout of the ASIC1a gene facilitated NPC migration and neurogenesis in the penumbra to improve behavioral recovery after stroke. Subsequently, ASIC1a gain of function partially abrogated this effect. Moreover, the administration of ASIC1a antagonists (amiloride or Psalmotoxin 1) promoted functional recovery by enhancing NPC migration and neurogenesis. Together, these results demonstrate targeting ASIC1a is a novel strategy potentiating NPC migration toward penumbra to repair lesions following ischemic stroke and even for other neurological diseases with the presence of niche acidosis.
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Affiliation(s)
- Hongfei Ge
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
- Medical Research Center, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
| | - Tengyuan Zhou
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
- Medical Research Center, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
| | - Chao Zhang
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
- Medical Research Center, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
| | - Yupeng Cun
- Pediatric Research Institute,
Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Children’s Hospital of Chongqing Medical University, 400014 Chongqing, China
| | - Weixiang Chen
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
| | - Yang Yang
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
| | - Qian Zhang
- Medical Research Center, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
| | - Huanhuan Li
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
| | - Jun Zhong
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
| | - Xuyang Zhang
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
| | - Hua Feng
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
| | - Rong Hu
- Department of Neurosurgery and Key Laboratory of Neurotrauma, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
- Medical Research Center, Southwest Hospital,
Third Military Medical University (Army Medical University), 400038 Chongqing, China
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8
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Hung CH, Chin Y, Fong YO, Lee CH, Han DS, Lin JH, Sun WH, Chen CC. Acidosis-related pain and its receptors as targets for chronic pain. Pharmacol Ther 2023; 247:108444. [PMID: 37210007 DOI: 10.1016/j.pharmthera.2023.108444] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/24/2023] [Accepted: 05/15/2023] [Indexed: 05/22/2023]
Abstract
Sensing acidosis is an important somatosensory function in responses to ischemia, inflammation, and metabolic alteration. Accumulating evidence has shown that acidosis is an effective factor for pain induction and that many intractable chronic pain diseases are associated with acidosis signaling. Various receptors have been known to detect extracellular acidosis and all express in the somatosensory neurons, such as acid sensing ion channels (ASIC), transient receptor potential (TRP) channels and proton-sensing G-protein coupled receptors. In addition to sense noxious acidic stimulation, these proton-sensing receptors also play a vital role in pain processing. For example, ASICs and TRPs are involved in not only nociceptive activation but also anti-nociceptive effects as well as some other non-nociceptive pathways. Herein, we review recent progress in probing the roles of proton-sensing receptors in preclinical pain research and their clinical relevance. We also propose a new concept of sngception to address the specific somatosensory function of acid sensation. This review aims to connect these acid-sensing receptors with basic pain research and clinical pain diseases, thus helping with better understanding the acid-related pain pathogenesis and their potential therapeutic roles via the mechanism of acid-mediated antinociception.
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Affiliation(s)
- Chih-Hsien Hung
- Department of Neurology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yin Chin
- Department of Life Science & Institute of Genome Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yi-On Fong
- Department of Neurology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Cheng-Han Lee
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Der-Shen Han
- Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, Bei-Hu Branch, Taipei, Taiwan
| | - Jiann-Her Lin
- Neuroscience Research Center, Taipei Medical University, Taipei, Taiwan; Department of Neurosurgery, Taipei Medical University Hospital, Taipei, Taiwan
| | - Wei-Hsin Sun
- Department of Life Science & Institute of Genome Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chih-Cheng Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan; Neuroscience Research Center, Taipei Medical University, Taipei, Taiwan; Neuroscience Program of Academia Sinica, Academia Sinica, Taipei, Taiwan.
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9
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Chafaï M, Delrocq A, Inquimbert P, Pidoux L, Delanoe K, Toft M, Brau F, Lingueglia E, Veltz R, Deval E. Dual contribution of ASIC1a channels in the spinal processing of pain information by deep projection neurons revealed by computational modeling. PLoS Comput Biol 2023; 19:e1010993. [PMID: 37068087 PMCID: PMC10109503 DOI: 10.1371/journal.pcbi.1010993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 03/03/2023] [Indexed: 04/18/2023] Open
Abstract
Dorsal horn of the spinal cord is an important crossroad of pain neuraxis, especially for the neuronal plasticity mechanisms that can lead to chronic pain states. Windup is a well-known spinal pain facilitation process initially described several decades ago, but its exact mechanism is still not fully understood. Here, we combine both ex vivo and in vivo electrophysiological recordings of rat spinal neurons with computational modeling to demonstrate a role for ASIC1a-containing channels in the windup process. Spinal application of the ASIC1a inhibitory venom peptides mambalgin-1 and psalmotoxin-1 (PcTx1) significantly reduces the ability of deep wide dynamic range (WDR) neurons to develop windup in vivo. All deep WDR-like neurons recorded from spinal slices exhibit an ASIC current with biophysical and pharmacological characteristics consistent with functional expression of ASIC1a homomeric channels. A computational model of WDR neuron supplemented with different ASIC1a channel parameters accurately reproduces the experimental data, further supporting a positive contribution of these channels to windup. It also predicts a calcium-dependent windup decrease for elevated ASIC conductances, a phenomenon that was experimentally validated using the Texas coral snake ASIC-activating toxin (MitTx) and calcium-activated potassium channel inhibitory peptides (apamin and iberiotoxin). This study supports a dual contribution to windup of calcium permeable ASIC1a channels in deep laminae projecting neurons, promoting it upon moderate channel activity, but ultimately leading to calcium-dependent windup inhibition associated to potassium channels when activity increases.
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Affiliation(s)
- Magda Chafaï
- Université Côte d'Azur, CNRS, IPMC, LabEx ICST, FHU InovPain, France
| | - Ariane Delrocq
- Université Côte d'Azur, CNRS, IPMC, LabEx ICST, FHU InovPain, France
- Inria Center of University Côte d'Azur, France, Valbonne, France
| | - Perrine Inquimbert
- Université de Strasbourg, CNRS, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg, France
| | - Ludivine Pidoux
- Université Côte d'Azur, CNRS, IPMC, LabEx ICST, FHU InovPain, France
| | - Kevin Delanoe
- Université Côte d'Azur, CNRS, IPMC, LabEx ICST, FHU InovPain, France
| | - Maurizio Toft
- Université Côte d'Azur, CNRS, IPMC, LabEx ICST, FHU InovPain, France
| | - Frederic Brau
- Université Côte d'Azur, CNRS, IPMC, LabEx ICST, FHU InovPain, France
| | - Eric Lingueglia
- Université Côte d'Azur, CNRS, IPMC, LabEx ICST, FHU InovPain, France
| | - Romain Veltz
- Inria Center of University Côte d'Azur, France, Valbonne, France
| | - Emmanuel Deval
- Université Côte d'Azur, CNRS, IPMC, LabEx ICST, FHU InovPain, France
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10
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Animal toxins: As an alternative therapeutic target following ischemic stroke condition. Life Sci 2023; 317:121365. [PMID: 36640901 DOI: 10.1016/j.lfs.2022.121365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 11/29/2022] [Accepted: 12/31/2022] [Indexed: 01/13/2023]
Abstract
Globally, Ischemic stroke (IS) has become the second leading cause of mortality and chronic disability. The process of IS has triggered by the blockages of blood vessels to form clots in the brain which initiates multiple interactions with the key signaling pathways, counting excitotoxicity, acidosis, ionic imbalance, inflammation, oxidative stress, and neuronal dysfunction of cells, and ultimately cells going under apoptosis. Currently, FDA has approved only tissue plasminogen activator therapy, which is effective against IS with few limitations. However, the mechanism of excitotoxicity and acidosis has spurred the investigation of a potential candidate for IS therapy. Acid-sensing ion channels (ASICs) and Voltage-gated Ca2+ channels (VDCCs) get activated and disturb the brain's normal physiology. Animal toxins are novel inhibitors of ASICs and VDCCs channels and have provided neuroprotective insights into the pathophysiology of IS. This review will discuss the potential directions of translational ASICs and VDCCs inhibitors research for clinical therapies.
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Sun HW, Chu XP, Simon RP, Xiong ZG, Leng TD. Inhibition of Acid-Sensing Ion Channels by KB-R7943, a Reverse Na+/Ca2+ Exchanger Inhibitor. Biomolecules 2023; 13:biom13030507. [PMID: 36979442 PMCID: PMC10046550 DOI: 10.3390/biom13030507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 02/27/2023] [Accepted: 03/07/2023] [Indexed: 03/12/2023] Open
Abstract
KB-R7943, an isothiourea derivative, is widely used as a pharmacological inhibitor of reverse sodium–calcium exchanger (NCX). It has been shown to have neuroprotective and analgesic effects in animal models; however, the detailed molecular mechanisms remain elusive. In the current study, we investigated whether KB-R7943 modulates acid-sensing ion channels (ASICs), a group of proton-gated cation channels implicated in the pathophysiology of various neurological disorders, using the whole-cell patch clamp techniques. Our data show that KB-R7943 irreversibly inhibits homomeric ASIC1a channels heterologously expressed in Chinese Hamster Ovary (CHO) cells in a use- and concentration-dependent manner. It also reversibly inhibits homomeric ASIC2a and ASIC3 channels in CHO cells. Both the transient and sustained current components of ASIC3 are inhibited. Furthermore, KB-R7943 inhibits ASICs in primary cultured peripheral and central neurons. It inhibits the ASIC-like currents in mouse dorsal root ganglion (DRG) neurons and the ASIC1a-like currents in mouse cortical neurons. The inhibition of the ASIC1a-like current is use-dependent and unrelated to its effect on NCX since neither of the other two well-characterized NCX inhibitors, including SEA0400 and SN-6, shows an effect on ASIC. Our data also suggest that the isothiourea group, which is lacking in other structurally related analogs that do not affect ASIC1a-like current, may serve as a critical functional group. In summary, we characterize KB-R7943 as a new ASIC inhibitor. It provides a novel pharmacological tool for the investigation of the functions of ASICs and could serve as a lead compound for developing small-molecule drugs for treating ASIC-related disorders.
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Affiliation(s)
- Hua-Wei Sun
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA 30310, USA
| | - Xiang-Ping Chu
- Department of Biomedical Sciences, University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108, USA
| | - Roger P. Simon
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA 30310, USA
| | - Zhi-Gang Xiong
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA 30310, USA
| | - Tian-Dong Leng
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA 30310, USA
- Correspondence:
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12
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Fuller MJ, Gupta SC, Fan R, Taugher-Hebl RJ, Wang GZ, Andrys NRR, Bera AK, Radley JJ, Wemmie JA. Investigating role of ASIC2 in synaptic and behavioral responses to drugs of abuse. Front Mol Biosci 2023; 10:1118754. [PMID: 36793786 PMCID: PMC9923001 DOI: 10.3389/fmolb.2023.1118754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 01/19/2023] [Indexed: 01/31/2023] Open
Abstract
Drugs of abuse produce rearrangements at glutamatergic synapses thought to contribute to drug-reinforced behaviors. Acid-Sensing Ion Channels (ASICs) have been suggested to oppose these effects, largely due to observations in mice lacking the ASIC1A subunit. However, the ASIC2A and ASIC2B subunits are known to interact with ASIC1A, and their potential roles in drugs of abuse have not yet been investigated. Therefore, we tested the effects of disrupting ASIC2 subunits in mice exposed to drugs of abuse. We found conditioned place preference (CPP) to both cocaine and morphine were increased in Asic2 -/- mice, which is similar to what was observed in Asic1a -/- mice. Because nucleus accumbens core (NAcc) is an important site of ASIC1A action, we examined expression of ASIC2 subunits there. By western blot ASIC2A was readily detected in wild-type mice, while ASIC2B was not, suggesting ASIC2A is the predominant subunit in nucleus accumbens core. An adeno-associated virus vector (AAV) was used to drive recombinant ASIC2A expression in nucleus accumbens core of Asic2 -/- mice, resulting in near normal protein levels. Moreover, recombinant ASIC2A integrated with endogenous ASIC1A subunits to form functional channels in medium spiny neurons (MSNs). However, unlike ASIC1A, region-restricted restoration of ASIC2A in nucleus accumbens core was not sufficient to affect cocaine or morphine conditioned place preference, suggesting effects of ASIC2 differ from those of ASIC1A. Supporting this contrast, we found that AMPA receptor subunit composition and the ratio of AMPA receptor-mediated current to NMDA receptor-mediated current (AMPAR/NMDAR) were normal in Asic2 -/- mice and responded to cocaine withdrawal similarly to wild-type animals. However, disruption of ASIC2 significantly altered dendritic spine morphology, and these effects differed from those reported previously in mice lacking ASIC1A. We conclude that ASIC2 plays an important role in drug-reinforced behavior, and that its mechanisms of action may differ from ASIC1A.
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Affiliation(s)
- Margaret J. Fuller
- Department of Psychiatry, University of Iowa, Iowa City, IA, United States
- Department of Veterans Affairs Medical Center, Iowa City, IA, United States
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, United States
- Medical Scientist Training Program, University of Iowa, Iowa City, IA, United States
| | - Subhash C. Gupta
- Department of Psychiatry, University of Iowa, Iowa City, IA, United States
- Department of Veterans Affairs Medical Center, Iowa City, IA, United States
| | - Rong Fan
- Department of Psychiatry, University of Iowa, Iowa City, IA, United States
- Department of Veterans Affairs Medical Center, Iowa City, IA, United States
| | - Rebecca J. Taugher-Hebl
- Department of Psychiatry, University of Iowa, Iowa City, IA, United States
- Department of Veterans Affairs Medical Center, Iowa City, IA, United States
| | - Grace Z. Wang
- Department of Psychiatry, University of Iowa, Iowa City, IA, United States
- Department of Veterans Affairs Medical Center, Iowa City, IA, United States
| | - Noah R. R. Andrys
- Department of Psychiatry, University of Iowa, Iowa City, IA, United States
- Department of Veterans Affairs Medical Center, Iowa City, IA, United States
| | - Amal K. Bera
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, Tamil Nadu, India
| | - Jason J. Radley
- Department of Psychological and Brain Sciences, University of Iowa, Iowa City, IA, United States
| | - John A. Wemmie
- Department of Psychiatry, University of Iowa, Iowa City, IA, United States
- Department of Veterans Affairs Medical Center, Iowa City, IA, United States
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, United States
- Medical Scientist Training Program, University of Iowa, Iowa City, IA, United States
- Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, United States
- Department of Neurosurgery, University of Iowa, Iowa City, IA, United States
- Interdisciplinary Graduate Program in Neuroscience, University of Iowa, Iowa City, IA, United States
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13
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The Role of Zinc in Modulating Acid-Sensing Ion Channel Function. Biomolecules 2023; 13:biom13020229. [PMID: 36830598 PMCID: PMC9953155 DOI: 10.3390/biom13020229] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/17/2023] [Accepted: 01/18/2023] [Indexed: 01/26/2023] Open
Abstract
Acid-sensing ion channels (ASICs) are proton-gated, voltage-independent sodium channels widely expressed throughout the central and peripheral nervous systems. They are involved in synaptic plasticity, learning/memory, fear conditioning and pain. Zinc, an important trace metal in the body, contributes to numerous physiological functions, with neurotransmission being of note. Zinc has been implicated in the modulation of ASICs by binding to specific sites on these channels and exerting either stimulatory or inhibitory effects depending on the ASIC subtype. ASICs have been linked to several neurological and psychological disorders, such as Alzheimer's disease, Parkinson's disease, ischemic stroke, epilepsy and cocaine addiction. Different ASIC isoforms contribute to the persistence of each of these neurological and psychological disorders. It is critical to understand how various zinc concentrations can modulate specific ASIC subtypes and how zinc regulation of ASICs can contribute to neurological and psychological diseases. This review elucidates zinc's structural interactions with ASICs and discusses the potential therapeutic implications zinc may have on neurological and psychological diseases through targeting ASICs.
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14
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Kaulich E, Grundy LJ, Schafer WR, Walker DS. The diverse functions of the DEG/ENaC family: linking genetic and physiological insights. J Physiol 2022; 601:1521-1542. [PMID: 36314992 PMCID: PMC10148893 DOI: 10.1113/jp283335] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 10/25/2022] [Indexed: 11/06/2022] Open
Abstract
The DEG/ENaC family of ion channels was defined based on the sequence similarity between degenerins (DEG) from the nematode Caenorhabditis elegans and subunits of the mammalian epithelial sodium channel (ENaC), and also includes a diverse array of non-voltage-gated cation channels from across animal phyla, including the mammalian acid-sensing ion channels (ASICs) and Drosophila pickpockets. ENaCs and ASICs have wide ranging medical importance; for example, ENaCs play an important role in respiratory and renal function, and ASICs in ischaemia and inflammatory pain, as well as being implicated in memory and learning. Electrophysiological approaches, both in vitro and in vivo, have played an essential role in establishing the physiological properties of this diverse family, identifying an array of modulators and implicating them in an extensive range of cellular functions, including mechanosensation, acid sensation and synaptic modulation. Likewise, genetic studies in both invertebrates and vertebrates have played an important role in linking our understanding of channel properties to function at the cellular and whole animal/behavioural level. Drawing together genetic and physiological evidence is essential to furthering our understanding of the precise cellular roles of DEG/ENaC channels, with the diversity among family members allowing comparative physiological studies to dissect the molecular basis of these diverse functions.
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Affiliation(s)
- Eva Kaulich
- Neurobiology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, UK
| | - Laura J Grundy
- Neurobiology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, UK
| | - William R Schafer
- Neurobiology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, UK.,Department of Biology, KU Leuven, Leuven, Belgium
| | - Denise S Walker
- Neurobiology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, UK
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15
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Verkest C, Salinas M, Diochot S, Deval E, Lingueglia E, Baron A. Mechanisms of Action of the Peptide Toxins Targeting Human and Rodent Acid-Sensing Ion Channels and Relevance to Their In Vivo Analgesic Effects. Toxins (Basel) 2022; 14:toxins14100709. [PMID: 36287977 PMCID: PMC9612379 DOI: 10.3390/toxins14100709] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 09/30/2022] [Accepted: 10/02/2022] [Indexed: 11/16/2022] Open
Abstract
Acid-sensing ion channels (ASICs) are voltage-independent H+-gated cation channels largely expressed in the nervous system of rodents and humans. At least six isoforms (ASIC1a, 1b, 2a, 2b, 3 and 4) associate into homotrimers or heterotrimers to form functional channels with highly pH-dependent gating properties. This review provides an update on the pharmacological profiles of animal peptide toxins targeting ASICs, including PcTx1 from tarantula and related spider toxins, APETx2 and APETx-like peptides from sea anemone, and mambalgin from snake, as well as the dimeric protein snake toxin MitTx that have all been instrumental to understanding the structure and the pH-dependent gating of rodent and human cloned ASICs and to study the physiological and pathological roles of native ASICs in vitro and in vivo. ASICs are expressed all along the pain pathways and the pharmacological data clearly support a role for these channels in pain. ASIC-targeting peptide toxins interfere with ASIC gating by complex and pH-dependent mechanisms sometimes leading to opposite effects. However, these dual pH-dependent effects of ASIC-inhibiting toxins (PcTx1, mambalgin and APETx2) are fully compatible with, and even support, their analgesic effects in vivo, both in the central and the peripheral nervous system, as well as potential effects in humans.
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Affiliation(s)
- Clément Verkest
- CNRS (Centre National de la Recherche Scientifique), IPMC (Institut de Pharmacologie Moléculaire et Cellulaire), LabEx ICST (Laboratory of Excellence in Ion Channel Science and Therapeutics), FHU InovPain (Fédération Hospitalo-Universitaire “Innovative Solutions in Refractory Chronic Pain”), Université Côte d’Azur, 660 Route des Lucioles, Sophia-Antipolis, 06560 Nice, France
- Department of Anesthesiology, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Miguel Salinas
- CNRS (Centre National de la Recherche Scientifique), IPMC (Institut de Pharmacologie Moléculaire et Cellulaire), LabEx ICST (Laboratory of Excellence in Ion Channel Science and Therapeutics), FHU InovPain (Fédération Hospitalo-Universitaire “Innovative Solutions in Refractory Chronic Pain”), Université Côte d’Azur, 660 Route des Lucioles, Sophia-Antipolis, 06560 Nice, France
| | - Sylvie Diochot
- CNRS (Centre National de la Recherche Scientifique), IPMC (Institut de Pharmacologie Moléculaire et Cellulaire), LabEx ICST (Laboratory of Excellence in Ion Channel Science and Therapeutics), FHU InovPain (Fédération Hospitalo-Universitaire “Innovative Solutions in Refractory Chronic Pain”), Université Côte d’Azur, 660 Route des Lucioles, Sophia-Antipolis, 06560 Nice, France
| | - Emmanuel Deval
- CNRS (Centre National de la Recherche Scientifique), IPMC (Institut de Pharmacologie Moléculaire et Cellulaire), LabEx ICST (Laboratory of Excellence in Ion Channel Science and Therapeutics), FHU InovPain (Fédération Hospitalo-Universitaire “Innovative Solutions in Refractory Chronic Pain”), Université Côte d’Azur, 660 Route des Lucioles, Sophia-Antipolis, 06560 Nice, France
| | - Eric Lingueglia
- CNRS (Centre National de la Recherche Scientifique), IPMC (Institut de Pharmacologie Moléculaire et Cellulaire), LabEx ICST (Laboratory of Excellence in Ion Channel Science and Therapeutics), FHU InovPain (Fédération Hospitalo-Universitaire “Innovative Solutions in Refractory Chronic Pain”), Université Côte d’Azur, 660 Route des Lucioles, Sophia-Antipolis, 06560 Nice, France
| | - Anne Baron
- CNRS (Centre National de la Recherche Scientifique), IPMC (Institut de Pharmacologie Moléculaire et Cellulaire), LabEx ICST (Laboratory of Excellence in Ion Channel Science and Therapeutics), FHU InovPain (Fédération Hospitalo-Universitaire “Innovative Solutions in Refractory Chronic Pain”), Université Côte d’Azur, 660 Route des Lucioles, Sophia-Antipolis, 06560 Nice, France
- Correspondence:
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16
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Zha XM, Xiong ZG, Simon RP. pH and proton-sensitive receptors in brain ischemia. J Cereb Blood Flow Metab 2022; 42:1349-1363. [PMID: 35301897 PMCID: PMC9274858 DOI: 10.1177/0271678x221089074] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 02/11/2022] [Accepted: 02/28/2022] [Indexed: 01/01/2023]
Abstract
Extracellular proton concentration is at 40 nM when pH is 7.4. In disease conditions such as brain ischemia, proton concentration can reach µM range. To respond to this increase in extracellular proton concentration, the mammalian brain expresses at least three classes of proton receptors. Acid-sensing ion channels (ASICs) are the main neuronal cationic proton receptor. The proton-activated chloride channel (PAC), which is also known as (aka) acid-sensitive outwardly rectifying anion channel (ASOR; TMEM206), mediates acid-induced chloride currents. Besides proton-activated channels, GPR4, GPR65 (aka TDAG8, T-cell death-associated gene 8), and GPR68 (aka OGR1, ovarian cancer G protein-coupled receptor 1) function as proton-sensitive G protein-coupled receptors (GPCRs). Though earlier studies on these GPCRs mainly focus on peripheral cells, we and others have recently provided evidence for their functional importance in brain injury. Specifically, GPR4 shows strong expression in brain endothelium, GPR65 is present in a fraction of microglia, while GPR68 exhibits predominant expression in brain neurons. Here, to get a better view of brain acid signaling and its contribution to ischemic injury, we will review the recent findings regarding the differential contribution of proton-sensitive GPCRs to cerebrovascular function, neuroinflammation, and neuronal injury following acidosis and brain ischemia.
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Affiliation(s)
- Xiang-ming Zha
- Division of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, Kansas City, MO, USA
| | - Zhi-Gang Xiong
- Department of Neurobiology, Morehouse School of Medicine, Atlanta, GA, USA
| | - Roger P Simon
- Department of Neurobiology, Morehouse School of Medicine, Atlanta, GA, USA
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17
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Zhang L, Zheng L, Yang X, Yao S, Wang H, An J, Jin H, Wen G, Tuo B. Pathology and physiology of acid‑sensitive ion channels in the digestive system (Review). Int J Mol Med 2022; 50:94. [PMID: 35616162 PMCID: PMC9170189 DOI: 10.3892/ijmm.2022.5150] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 05/11/2022] [Indexed: 11/16/2022] Open
Abstract
As a major proton-gated cation channel, acid-sensitive ion channels (ASICs) can perceive large extracellular pH changes. ASICs play an important role in the occurrence and development of diseases of various organs and tissues including in the heart, brain, and gastrointestinal tract, as well as in tumor proliferation, invasion, and metastasis in acidosis and regulation of an acidic microenvironment. The permeability of ASICs to sodium and calcium ions is the basis of their physiological and pathological roles in the body. This review summarizes the physiological and pathological mechanisms of ASICs in digestive system diseases, which plays an important role in the early diagnosis, treatment, and prognosis of digestive system diseases related to ASIC expression.
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Affiliation(s)
- Li Zhang
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Liming Zheng
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Xingyue Yang
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Shun Yao
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Hui Wang
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Jiaxing An
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Hai Jin
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Guorong Wen
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Biguang Tuo
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
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18
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Bhashyam A, Lubinus M, Filmore E, Wilson L, Williams J, Gonzalez Ramos O, Bhai S. Pain profile and opioid medication use in patients with idiopathic inflammatory myopathies. Rheumatology (Oxford) 2022; 62:264-269. [PMID: 35579332 PMCID: PMC9788817 DOI: 10.1093/rheumatology/keac271] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 04/24/2022] [Accepted: 04/24/2022] [Indexed: 01/01/2023] Open
Abstract
OBJECTIVES Pain is commonly reported in people living with myositis. This study assesses the presence of pain in the subtypes of myositis as well as the frequency of opioid and non-opioid pain medication use. METHODS A survey was developed and distributed by Myositis Support and Understanding, a patient-led advocacy organization, to members of its group. Multivariate logistic regression analysis and chi-squared tests were performed. RESULTS A total of 468 participants completed the survey. A total of 423 participants (DM n = 183, PM n = 109 and IBM n = 131) were included, based on reported diagnosis, for final analysis. Some 91.5% of myositis participants reported current or past pain, with 99% attributing their pain to myositis. There was a lower likelihood of pain in participants aged >60 years [odds ratio (OR) 0.2, 95% confidence interval (CI) 0.1, 0.6, P = 0.003]. The percentage of participants reporting pain was statistically different based on myositis type (DM 97.2%, IBM 80.9% and PM 94.5%, P < 0.001), with a higher likelihood of pain in DM compared with IBM (OR 3.7, 95% CI 1.3, 10.2, P = 0.011). There was a lower likelihood of pain in participants aged >60 years (OR 0.2, 95% CI 0.1, 0.6, P = 0.003). Of the 387 participants reporting pain, 335 reported using pain medications (69% prescribed opioids). Male sex, age >60 years and myositis subtype were not associated with likelihood of non-opioid use. CONCLUSION Pain is a commonly reported symptom in myositis with variable treatment strategies, including opioid medications. This study highlights the importance of addressing pain as part of myositis treatment as well as the need for future studies understanding treatment effectiveness.
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Affiliation(s)
- Abhiram Bhashyam
- Department of Orthopedics, Massachusetts General Hospital, Boston, MA,Myositis Support and Understanding, Lincoln, DE
| | - Manuel Lubinus
- Department of Orthopedics, Massachusetts General Hospital, Boston, MA
| | | | - Lynn Wilson
- Myositis Support and Understanding, Lincoln, DE
| | | | | | - Salman Bhai
- Correspondence to: Salman Bhai, Institute for Exercise and Environmental Medicine, 7232 Greenville Ave. Ste. 435, Dallas, TX 75231, USA. E-mail:
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Alasmari F, Sari DB, Alhaddad H, Al-Rejaie SS, Sari Y. Interactive role of acid sensing ion channels and glutamatergic system in opioid dependence. Neurosci Biobehav Rev 2022; 135:104581. [PMID: 35181397 DOI: 10.1016/j.neubiorev.2022.104581] [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: 11/11/2021] [Revised: 02/03/2022] [Accepted: 02/12/2022] [Indexed: 11/21/2022]
Abstract
Dysregulation in glutamatergic receptors and transporters has been found to mediate drugs of abuse, including morphine. Among glutamate receptors, ionotropic glutamate receptors (iGluRs) are altered with exposure to drugs of abuse. Acid-sensing ion channels (ASICs) are ligand (H+)-gated channels, which are expressed at the excitatory synaptic clefts and play a role in drug dependence. Overexpression of a specific ASIC subtype, ASIC1a, attenuated reinstatement of cocaine. ASICs are revealed to be involved in cocaine and morphine seeking behaviors, and these effects are mediated through modulation of glutamatergic receptors. In this review, we discussed the interactive role of ASICs and glutamate receptors, mainly iGluRs, in opioid dependence. ASICs are also expressed in astrocytes and are suggested to be involved on regulating glutamate uptake. However, little is known about the coupling between ASICs and the astroglial glutamate transporters. In addition, this review discussed the role of nitric oxide in the modulation of ASIC function and potentially opioid dependence. We also discussed the role of ASICs in the modulation of the function of both glutamatergic receptors in post-synaptic neurons and glutamatergic transporters in astrocytes in animals exposed to drugs of abuse.
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Affiliation(s)
- Fawaz Alasmari
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia; Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH, USA.
| | - Deen B Sari
- Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH, USA
| | - Hasan Alhaddad
- Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH, USA
| | - Salim S Al-Rejaie
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Youssef Sari
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia; Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH, USA.
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20
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Heusser SA, Borg CB, Colding JM, Pless SA. Conformational decoupling in acid-sensing ion channels uncovers mechanism and stoichiometry of PcTx1-mediated inhibition. eLife 2022; 11:73384. [PMID: 35156612 PMCID: PMC8871370 DOI: 10.7554/elife.73384] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 02/11/2022] [Indexed: 01/10/2023] Open
Abstract
Acid-sensing ion channels (ASICs) are trimeric proton-gated cation channels involved in fast synaptic transmission. Pharmacological inhibition of ASIC1a reduces neurotoxicity and stroke infarct volumes, with the cysteine knot toxin psalmotoxin-1 (PcTx1) being one of the most potent and selective inhibitors. PcTx1 binds at the subunit interface in the extracellular domain (ECD), but the mechanism and conformational consequences of the interaction, as well as the number of toxin molecules required for inhibition, remain unknown. Here, we use voltage-clamp fluorometry and subunit concatenation to decipher the mechanism and stoichiometry of PcTx1 inhibition of ASIC1a. Besides the known inhibitory binding mode, we propose PcTx1 to have at least two additional binding modes that are decoupled from the pore. One of these modes induces a long-lived ECD conformation that reduces the activity of an endogenous neuropeptide. This long-lived conformational state is proton-dependent and can be destabilized by a mutation that decreases PcTx1 sensitivity. Lastly, the use of concatemeric channel constructs reveals that disruption of a single PcTx1 binding site is sufficient to destabilize the toxin-induced conformation, while functional inhibition is not impaired until two or more binding sites are mutated. Together, our work provides insight into the mechanism of PcTx1 inhibition of ASICs and uncovers a prolonged conformational change with possible pharmacological implications.
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Affiliation(s)
- Stephanie A Heusser
- Department of Drug Design and Pharmacology, University of Copenhagen, Copehagen, Denmark
| | - Christian B Borg
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Janne M Colding
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Stephan A Pless
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
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21
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Sivils A, Yang F, Wang JQ, Chu XP. Acid-Sensing Ion Channel 2: Function and Modulation. MEMBRANES 2022; 12:membranes12020113. [PMID: 35207035 PMCID: PMC8880099 DOI: 10.3390/membranes12020113] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/14/2022] [Accepted: 01/17/2022] [Indexed: 01/08/2023]
Abstract
Acid-sensing ion channels (ASICs) have an important influence on human physiology and pathology. They are members of the degenerin/epithelial sodium channel family. Four genes encode at least six subunits, which combine to form a variety of homotrimers and heterotrimers. Of these, ASIC1a homotrimers and ASIC1a/2 heterotrimers are most widely expressed in the central nervous system (CNS). Investigations into the function of ASIC1a in the CNS have revealed a wealth of information, culminating in multiple contemporary reviews. The lesser-studied ASIC2 subunits are in need of examination. This review will focus on ASIC2 in health and disease, with discussions of its role in modulating ASIC function, synaptic targeting, cardiovascular responses, and pharmacology, while exploring evidence of its influence in pathologies such as ischemic brain injury, multiple sclerosis, epilepsy, migraines, drug addiction, etc. This information substantiates the ASIC2 protein as a potential therapeutic target for various neurological, psychological, and cerebrovascular diseases.
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Affiliation(s)
| | | | | | - Xiang-Ping Chu
- Correspondence: ; Tel.: +1-816-235-2248; Fax: +1-816-235-6517
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22
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Diochot S. Pain-related toxins in scorpion and spider venoms: a face to face with ion channels. J Venom Anim Toxins Incl Trop Dis 2021; 27:e20210026. [PMID: 34925480 PMCID: PMC8667759 DOI: 10.1590/1678-9199-jvatitd-2021-0026] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 05/10/2021] [Indexed: 12/12/2022] Open
Abstract
Pain is a common symptom induced during envenomation by spiders and scorpions.
Toxins isolated from their venom have become essential tools for studying the
functioning and physiopathological role of ion channels, as they modulate their
activity. In particular, toxins that induce pain relief effects can serve as a
molecular basis for the development of future analgesics in humans. This review
provides a summary of the different scorpion and spider toxins that directly
interact with pain-related ion channels, with inhibitory or stimulatory effects.
Some of these toxins were shown to affect pain modalities in different animal
models providing information on the role played by these channels in the pain
process. The close interaction of certain gating-modifier toxins with membrane
phospholipids close to ion channels is examined along with molecular approaches
to improve selectivity, affinity or bioavailability in vivo for
therapeutic purposes.
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Affiliation(s)
- Sylvie Diochot
- Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), Centre National de la Recherche Scientifique (CNRS) UMR 7275 et Université Côte d'Azur (UCA), 06560 Valbonne, France. Institut de Pharmacologie Moléculaire et Cellulaire Centre National de la Recherche Scientifique Université Côte d'Azur Valbonne France
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23
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Pidoplichko VI, Aroniadou-Anderjaska V, Figueiredo TH, Wilbraham C, Braga MFM. Increased inhibitory activity in the basolateral amygdala and decreased anxiety during estrus: A potential role for ASIC1a channels. Brain Res 2021; 1770:147628. [PMID: 34454948 DOI: 10.1016/j.brainres.2021.147628] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 08/13/2021] [Accepted: 08/16/2021] [Indexed: 11/29/2022]
Abstract
The amygdala is central to emotional behavior, and the excitability level of the basolateral nucleus of the amygdala (BLA) is associated with the level of anxiety. The excitability of neuronal networks is significantly controlled by GABAergic inhibition. Here, we investigated whether GABAergic inhibition in the BLA is altered during the rat estrous cycle. In rat amygdala slices, most principal BLA neurons display spontaneous IPSCs (sIPSCs) in the form of "bursts" of inhibitory currents, occurring rhythmically at a frequency of about 0.5 Hz. The percentage of BLA neurons displaying sIPSC bursts, along with the inhibitory charge transferred by sIPSCs and the frequency of sIPSC bursts, were significantly increased during the estrus phase; increased inhibition was accompanied by reduced anxiety in the open field, the light-dark box, and the acoustic startle response tests. sIPSC bursts were blocked by ibuprofen, an antagonist of acid-sensing-1a channels (ASIC1a), whose activity is known to increase by decreasing temperature. A transient reduction in the temperature of the slice medium, strengthened the sIPSCs bursts; this effect was blocked in the presence of ibuprofen. Further analysis of the sIPSC bursts during estrus showed significantly stronger rhythmic inhibitory activity in early estrus, when body temperature drops, compared with late estrus. To the extent that these results may relate to humans, it is suggested that "a calmer amygdala" due to increased inhibitory activity may underlie the positive affect in women around ovulation time. ASIC1a may contribute to increased inhibition, with their activity facilitated by the body-temperature drop preceding ovulation.
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Affiliation(s)
- Volodymyr I Pidoplichko
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA.
| | - Vassiliki Aroniadou-Anderjaska
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA; Department of Psychiatry, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA.
| | - Taiza H Figueiredo
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA.
| | - Camilla Wilbraham
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA.
| | - Maria F M Braga
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA; Department of Psychiatry, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA.
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24
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Cullinan MM, Klipp RC, Bankston JR. Regulation of acid-sensing ion channels by protein binding partners. Channels (Austin) 2021; 15:635-647. [PMID: 34704535 PMCID: PMC8555555 DOI: 10.1080/19336950.2021.1976946] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Acid-sensing ion channels (ASICs) are a family of proton-gated cation channels that contribute to a diverse array of functions including pain sensation, cell death during ischemia, and more broadly to neurotransmission in the central nervous system. There is an increasing interest in understanding the physiological regulatory mechanisms of this family of channels. ASICs have relatively short N- and C-termini, yet a number of proteins have been shown to interact with these domains both in vitro and in vivo. These proteins can impact ASIC gating, localization, cell-surface expression, and regulation. Like all ion channels, it is important to understand the cellular context under which ASICs function in neurons and other cells. Here we will review what is known about a number of these potentially important regulatory molecules.
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Affiliation(s)
- Megan M Cullinan
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Robert C Klipp
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - John R Bankston
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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25
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Páez O, Segura-Chama P, Almanza A, Pellicer F, Mercado F. Properties and Differential Expression of H + Receptors in Dorsal Root Ganglia: Is a Labeled-Line Coding for Acid Nociception Possible? Front Physiol 2021; 12:733267. [PMID: 34764880 PMCID: PMC8576393 DOI: 10.3389/fphys.2021.733267] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 10/05/2021] [Indexed: 11/13/2022] Open
Abstract
Pain by chemical irritants is one of the less well-described aspects of nociception. The acidic substance is the paradigm of the chemical noxious compound. An acidic insult on cutaneous, subcutaneous and muscle tissue results in pain sensation. Acid (or H+) has at least two main receptor channels in dorsal root ganglia (DRG) nociceptors: the heat receptor transient receptor potential vanilloid 1 (TRPV1) and the acid-sensing ionic channels (ASICs). TRPV1 is a low-sensitivity H+ receptor, whereas ASIC channels display a higher H+ sensitivity of at least one order of magnitude. In this review, we first describe the functional and structural characteristics of these and other H+-receptor candidates and the biophysics of their responses to low pH. Additionally, we compile reports of the expression of these H+-receptors (and other possible complementary proteins) within the DRG and compare these data with mRNA expression profiles from single-cell sequencing datasets for ASIC3, ASIC1, transient receptor potential Ankiryn subtype 1 (TRPA1) and TRPV1. We show that few nociceptor subpopulations (discriminated by unbiased classifications) combine acid-sensitive channels. This comparative review is presented in light of the accumulating evidence for labeled-line coding for most noxious sensory stimuli.
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Affiliation(s)
- Omar Páez
- Laboratorio de Fisiología Celular, Dirección de Investigaciones en Nuerociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, Ciudad de México, Mexico
| | - Pedro Segura-Chama
- Laboratorio de Fisiología Celular, Dirección de Investigaciones en Nuerociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, Ciudad de México, Mexico
- Cátedras CONACyT, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, Ciudad de México, Mexico
| | - Angélica Almanza
- Laboratorio de Fisiología Celular, Dirección de Investigaciones en Nuerociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, Ciudad de México, Mexico
| | - Francisco Pellicer
- Laboratorio de Neurofisiología Integrativa, Dirección de Investigaciones en Neurociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, Ciudad de México, Mexico
| | - Francisco Mercado
- Laboratorio de Fisiología Celular, Dirección de Investigaciones en Nuerociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, Ciudad de México, Mexico
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26
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King P, Wan J, Guo AA, Guo S, Jiang Y, Liu M. Regulation of gliomagenesis and stemness through acid sensor ASIC1a. Int J Oncol 2021; 59:82. [PMID: 34515325 PMCID: PMC8448544 DOI: 10.3892/ijo.2021.5262] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 07/28/2021] [Indexed: 01/29/2023] Open
Abstract
Glioblastoma multiforme (GBM) is the most prevalent and aggressive type of adult gliomas. Despite intensive therapy including surgery, radiation, and chemotherapy, invariable tumor recurrence occurs, which suggests that glioblastoma stem cells (GSCs) render these tumors persistent. Recently, the induction of GSC differentiation has emerged as an alternative method to treat GBM, and most of the current studies aim to convert GSCs to neurons by a combination of transcriptional factors. As the tumor microenvironment is typically acidic due to increased glycolysis and consequently leads to an increased production of lactic acid in tumor cells, in the present study, the role of acid‑sensing ion channel 1a (ASIC1a), an acid sensor, was explored as a tumor suppressor in gliomagenesis and stemness. The bioinformatics data from The Cancer Genome Atlas revealed that ASIC1 expression levels in GBM tumor tissues were lower than those in normal brain, and glioma patients with high ASIC1 expression had longer survival than those with low ASIC1 expression. Our immunohistochemistry data from tissue microarray revealed that ASIC1a expression was negatively associated with glioma grading. Functional studies revealed that the downregulation of ASIC1a promoted glioma cell proliferation and invasion, while upregulation of ASIC1a inhibited their proliferation and invasion. Furthermore, ASIC1a suppressed growth and proliferation of glioma cells through G1/S arrest and apoptosis induction. Mechanistically, ASIC1a negatively modulated glioma stemness via inhibition of the Notch signaling pathway and GSC markers CD133 and aldehyde dehydrogenase 1. ASIC1a is a tumor suppressor in gliomagenesis and stemness and may serve as a promising prognostic biomarker and target for GBM patients.
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Affiliation(s)
- Pendelton King
- Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA 30310, USA
| | - Jingwei Wan
- Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA 30310, USA
- Department of Neurosurgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| | - Alyssa Aihui Guo
- Department of Biomedical Sciences, School of Medicine Greenville, University of South Carolina, Greenville, SC 29605, USA
| | - Shanchun Guo
- Department of Chemistry, Xavier University, New Orleans, LA 70125, USA
| | - Yugang Jiang
- Department of Neurosurgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| | - Mingli Liu
- Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA 30310, USA
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27
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Lim J, Tai HH, Liao WH, Chu YC, Hao CM, Huang YC, Lee CH, Lin SS, Hsu S, Chien YC, Lai DM, Chen WS, Chen CC, Wang JL. ASIC1a is required for neuronal activation via low-intensity ultrasound stimulation in mouse brain. eLife 2021; 10:e61660. [PMID: 34569932 PMCID: PMC8510583 DOI: 10.7554/elife.61660] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 09/22/2021] [Indexed: 12/20/2022] Open
Abstract
Accumulating evidence has shown transcranial low-intensity ultrasound can be potentially a non-invasive neural modulation tool to treat brain diseases. However, the underlying mechanism remains elusive and the majority of studies on animal models applying rather high-intensity ultrasound that cannot be safely used in humans. Here, we showed low-intensity ultrasound was able to activate neurons in the mouse brain and repeated ultrasound stimulation resulted in adult neurogenesis in specific brain regions. In vitro calcium imaging studies showed that a specific ultrasound stimulation mode, which combined with both ultrasound-induced pressure and acoustic streaming mechanotransduction, is required to activate cultured cortical neurons. ASIC1a and cytoskeletal proteins were involved in the low-intensity ultrasound-mediated mechanotransduction and cultured neuron activation, which was inhibited by ASIC1a blockade and cytoskeleton-modified agents. In contrast, the inhibition of mechanical-sensitive channels involved in bilayer-model mechanotransduction like Piezo or TRP proteins did not repress the ultrasound-mediated neuronal activation as efficiently. The ASIC1a-mediated ultrasound effects in mouse brain such as immediate response of ERK phosphorylation and DCX marked neurogenesis were statistically significantly compromised by ASIC1a gene deletion. Collated data suggest that ASIC1a is the molecular determinant involved in the mechano-signaling of low-intensity ultrasound that modulates neural activation in mouse brain.
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Affiliation(s)
- Jormay Lim
- Department of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan UniversityTaipeiTaiwan
| | - Hsiao-Hsin Tai
- Department of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan UniversityTaipeiTaiwan
| | - Wei-Hao Liao
- Department of Physical Medicine and Rehabilitation, National Taiwan Hospital UniversityTaipeiTaiwan
| | - Ya-Cherng Chu
- Department of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan UniversityTaipeiTaiwan
| | - Chen-Ming Hao
- Department of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan UniversityTaipeiTaiwan
| | - Yueh-Chun Huang
- Department of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan UniversityTaipeiTaiwan
| | - Cheng-Han Lee
- Institute of Biomedical Sciences, Academia SinicaTaipeiTaiwan
| | - Shao-Shien Lin
- Department of Surgery, National Taiwan Hospital UniversityTaipeiTaiwan
| | - Sherry Hsu
- Department of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan UniversityTaipeiTaiwan
| | - Ya-Chih Chien
- Institute of Biomedical Sciences, Academia SinicaTaipeiTaiwan
| | - Dar-Ming Lai
- Department of Surgery, National Taiwan Hospital UniversityTaipeiTaiwan
| | - Wen-Shiang Chen
- Department of Physical Medicine and Rehabilitation, National Taiwan Hospital UniversityTaipeiTaiwan
| | - Chih-Cheng Chen
- Institute of Biomedical Sciences, Academia SinicaTaipeiTaiwan
| | - Jaw-Lin Wang
- Department of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan UniversityTaipeiTaiwan
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28
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Leisle L, Margreiter M, Ortega-Ramírez A, Cleuvers E, Bachmann M, Rossetti G, Gründer S. Dynorphin Neuropeptides Decrease Apparent Proton Affinity of ASIC1a by Occluding the Acidic Pocket. J Med Chem 2021; 64:13299-13311. [PMID: 34461722 DOI: 10.1021/acs.jmedchem.1c00447] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Prolonged acidosis, as it occurs during ischemic stroke, induces neuronal death via acid-sensing ion channel 1a (ASIC1a). Concomitantly, it desensitizes ASIC1a, highlighting the pathophysiological significance of modulators of ASIC1a acid sensitivity. One such modulator is the opioid neuropeptide big dynorphin (Big Dyn) which binds to ASIC1a and enhances its activity during prolonged acidosis. The molecular determinants and dynamics of this interaction remain unclear, however. Here, we present a molecular interaction model showing a dynorphin peptide inserting deep into the acidic pocket of ASIC1a. We confirmed experimentally that the interaction is predominantly driven by electrostatic forces, and using noncanonical amino acids as photo-cross-linkers, we identified 16 residues in ASIC1a contributing to Big Dyn binding. Covalently tethering Big Dyn to its ASIC1a binding site dramatically decreased the proton sensitivity of channel activation, suggesting that Big Dyn stabilizes a resting conformation of ASIC1a and dissociates from its binding site during channel opening.
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Affiliation(s)
- Lilia Leisle
- Institute of Physiology, RWTH Aachen University, 52074 Aachen, Germany
| | - Michael Margreiter
- Computational Biomedicine-Institute for Advanced Simulation/Institute of Neuroscience and Medicine, Forschungszentrum Jülich, 52425 Jülich, Germany.,Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany
| | | | - Elinor Cleuvers
- Institute of Physiology, RWTH Aachen University, 52074 Aachen, Germany
| | - Michèle Bachmann
- Institute of Physiology, RWTH Aachen University, 52074 Aachen, Germany
| | - Giulia Rossetti
- Computational Biomedicine-Institute for Advanced Simulation/Institute of Neuroscience and Medicine, Forschungszentrum Jülich, 52425 Jülich, Germany.,Jülich Supercomputing Center (JSC), Forschungszentrum Jülich, 52425 Jülich, Germany.,Department of Neurology, RWTH Aachen University, 52074 Aachen, Germany
| | - Stefan Gründer
- Institute of Physiology, RWTH Aachen University, 52074 Aachen, Germany
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29
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Foster VS, Rash LD, King GF, Rank MM. Acid-Sensing Ion Channels: Expression and Function in Resident and Infiltrating Immune Cells in the Central Nervous System. Front Cell Neurosci 2021; 15:738043. [PMID: 34602982 PMCID: PMC8484650 DOI: 10.3389/fncel.2021.738043] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 08/30/2021] [Indexed: 11/15/2022] Open
Abstract
Peripheral and central immune cells are critical for fighting disease, but they can also play a pivotal role in the onset and/or progression of a variety of neurological conditions that affect the central nervous system (CNS). Tissue acidosis is often present in CNS pathologies such as multiple sclerosis, epileptic seizures, and depression, and local pH is also reduced during periods of ischemia following stroke, traumatic brain injury, and spinal cord injury. These pathological increases in extracellular acidity can activate a class of proton-gated channels known as acid-sensing ion channels (ASICs). ASICs have been primarily studied due to their ubiquitous expression throughout the nervous system, but it is less well recognized that they are also found in various types of immune cells. In this review, we explore what is currently known about the expression of ASICs in both peripheral and CNS-resident immune cells, and how channel activation during pathological tissue acidosis may lead to altered immune cell function that in turn modulates inflammatory pathology in the CNS. We identify gaps in the literature where ASICs and immune cell function has not been characterized, such as neurotrauma. Knowledge of the contribution of ASICs to immune cell function in neuropathology will be critical for determining whether the therapeutic benefits of ASIC inhibition might be due in part to an effect on immune cells.
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Affiliation(s)
- Victoria S. Foster
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
| | - Lachlan D. Rash
- School of Biomedical Sciences, The University of Queensland, St Lucia, QLD, Australia
| | - Glenn F. King
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, St Lucia, QLD, Australia
| | - Michelle M. Rank
- Anatomy and Physiology, Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, VIC, Australia
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30
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Native expression of ASIC1a and ASIC1b human homologues in the HEK 293 cell line allows pharmacological evaluation of analgesics targeting acid sensation in humans. Neuroreport 2021; 31:865-870. [PMID: 32453026 DOI: 10.1097/wnr.0000000000001465] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Nociceptors arising from the dorsal root ganglia (DRG) express acid-sensing ion channel-1 (ASIC1) subtypes to mediate the perception of inflammatory and neuropathic pain, and as such, these receptors are attractive targets for the development of analgesics for these painful conditions. Nevertheless, given that the human and rodent DRG differ considerably in subtype proportions of ASIC1 and that the pharmacological properties of rodent ASIC1 subtypes and their human homologues are distinct, ASIC1 inhibitors that demonstrate analgesic properties in rodents may not necessarily be effective in preventing pain in humans. In this study, we show that human embryonic kidney (HEK) 293 cells, which are routinely used as a cellular vehicle for the heterologous expression and pharmacological characterization of receptors and ion channels, natively transcribe the human homologues of ASIC1a and ASIC1b at similar proportions to those found in the human DRG. Importantly, HEK 293 ASIC1 is sensitive to inhibition by amiloride, ethylisopropyl amiloride, and the snake toxin mambalgin-1, but insensitive to inhibition by the ASIC1a inhibitor psalmotoxin-1 when applied at a physiological conditioning pH. Given that the human DRG transcribes the same set of ASIC1 subtypes as HEK 293 cells, our data support the notion that mambalgin-1 may be effective against acid pain sensation in humans. Moreover, our data suggest that the HEK 293 cell line may be a suitable tool for pharmacological screening and characterization of heteromeric human ASIC1.
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31
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Wu BM, Bargaineer J, Zhang L, Yang T, Xiong ZG, Leng TD. Upregulation of acid sensing ion channel 1a (ASIC1a) by hydrogen peroxide through the JNK pathway. Acta Pharmacol Sin 2021; 42:1248-1255. [PMID: 33184449 PMCID: PMC8285496 DOI: 10.1038/s41401-020-00559-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 10/18/2020] [Indexed: 02/02/2023] Open
Abstract
Oxidative stress is intimately tied to neurodegenerative diseases, including Parkinson's disease and amyotrophic lateral sclerosis, and acute injuries, such as ischemic stroke and traumatic brain injury. Acid sensing ion channel 1a (ASIC1a), a proton-gated ion channel, has been shown to be involved in the pathogenesis of these diseases. However, whether oxidative stress affects the expression of ASIC1a remains elusive. In the current study, we examined the effect of hydrogen peroxide (H2O2), a major reactive oxygen species (ROS), on ASIC1a protein expression and channel function in NS20Y cells and primary cultured mouse cortical neurons. We found that treatment of the cells with H2O2 (20 µM) for 6 h or longer increased ASIC1a protein expression and ASIC currents without causing significant cell injury. H2O2 incubation activated mitogen-activated protein kinases (MAPKs) pathways, including the extracellular signal-regulated kinase1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), and p38 pathways. We found that neither inhibition of the MEK/ERK pathway by U0126 nor inhibition of the p38 pathway by SB203580 affected H2O2-induced ASIC1a expression, whereas inhibition of the JNK pathway by SP600125 potently decreased ASIC1a expression and abolished the H2O2-mediated increase in ASIC1a expression and ASIC currents. Furthermore, we found that H2O2 pretreatment increased the sensitivity of ASIC currents to the ASIC1a inhibitor PcTx1, providing additional evidence that H2O2 increases the expression of functional ASIC1a channels. Together, our data demonstrate that H2O2 increases ASIC1a expression/activation through the JNK signaling pathway, which may provide insight into the pathogenesis of neurological disorders that involve both ROS and activation of ASIC1a.
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Affiliation(s)
- Bao-Ming Wu
- Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA, 30310, USA
| | - Jaree Bargaineer
- Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA, 30310, USA
| | - Ling Zhang
- Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA, 30310, USA
| | - Tao Yang
- Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA, 30310, USA
| | - Zhi-Gang Xiong
- Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA, 30310, USA.
| | - Tian-Dong Leng
- Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA, 30310, USA.
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32
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Gornati D, Ciccone R, Vinciguerra A, Ippati S, Pannaccione A, Petrozziello T, Pizzi E, Hassan A, Colombo E, Barbini S, Milani M, Caccavone C, Randazzo P, Muzio L, Annunziato L, Menegon A, Secondo A, Mastrangelo E, Pignataro G, Seneci P. Synthesis and Characterization of Novel Mono- and Bis-Guanyl Hydrazones as Potent and Selective ASIC1 Inhibitors Able to Reduce Brain Ischemic Insult. J Med Chem 2021; 64:8333-8353. [PMID: 34097384 DOI: 10.1021/acs.jmedchem.1c00305] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Acid-sensitive ion channels (ASICs) are sodium channels partially permeable to Ca2+ ions, listed among putative targets in central nervous system (CNS) diseases in which a pH modification occurs. We targeted novel compounds able to modulate ASIC1 and to reduce the progression of ischemic brain injury. We rationally designed and synthesized several diminazene-inspired diaryl mono- and bis-guanyl hydrazones. A correlation between their predicted docking affinities for the acidic pocket (AcP site) in chicken ASIC1 and their inhibition of homo- and heteromeric hASIC1 channels in HEK-293 cells was found. Their activity on murine ASIC1a currents and their selectivity vs mASIC2a were assessed in engineered CHO-K1 cells, highlighting a limited isoform selectivity. Neuroprotective effects were confirmed in vitro, on primary rat cortical neurons exposed to oxygen-glucose deprivation followed by reoxygenation, and in vivo, in ischemic mice. Early lead 3b, showing a good selectivity for hASIC1 in human neurons, was neuroprotective against focal ischemia induced in mice.
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Affiliation(s)
- Davide Gornati
- Chemistry Department, University of Milan, Via Golgi 19, 20133 Milan, Italy
| | - Roselia Ciccone
- Division of Pharmacology, Department of Neuroscience, School of Medicine, University of Naples Federico II, Via Pansini 5, I-80131 Naples, Italy
| | - Antonio Vinciguerra
- Division of Pharmacology, Department of Neuroscience, School of Medicine, University of Naples Federico II, Via Pansini 5, I-80131 Naples, Italy
| | - Stefania Ippati
- Experimental Imaging Center, ALEMBIC-Advanced Light and Electron Microscopy BioImaging Center, San Raffaele Scientific Institute, Via Olgettina 60, I-20132 Milan, Italy
| | - Anna Pannaccione
- Division of Pharmacology, Department of Neuroscience, School of Medicine, University of Naples Federico II, Via Pansini 5, I-80131 Naples, Italy
| | - Tiziana Petrozziello
- Division of Pharmacology, Department of Neuroscience, School of Medicine, University of Naples Federico II, Via Pansini 5, I-80131 Naples, Italy
| | - Erika Pizzi
- Experimental Imaging Center, ALEMBIC-Advanced Light and Electron Microscopy BioImaging Center, San Raffaele Scientific Institute, Via Olgettina 60, I-20132 Milan, Italy
| | - Amal Hassan
- National Research Council-Biophysics Institute (CNR-IBF), and Biosciences Department University of Milan, Via Celoria, 26, I-20133 Milan, Italy
| | - Eleonora Colombo
- Chemistry Department, University of Milan, Via Golgi 19, 20133 Milan, Italy
| | - Stefano Barbini
- Chemistry Department, University of Milan, Via Golgi 19, 20133 Milan, Italy
| | - Mario Milani
- National Research Council-Biophysics Institute (CNR-IBF), and Biosciences Department University of Milan, Via Celoria, 26, I-20133 Milan, Italy
| | - Cecilia Caccavone
- Experimental Imaging Center, ALEMBIC-Advanced Light and Electron Microscopy BioImaging Center, San Raffaele Scientific Institute, Via Olgettina 60, I-20132 Milan, Italy
| | | | - Luca Muzio
- INSPE-Institute of Experimental Neurology, San Raffaele Scientific Institute, Via Olgettina 60, I-20132 Milan, Italy
| | | | - Andrea Menegon
- Experimental Imaging Center, ALEMBIC-Advanced Light and Electron Microscopy BioImaging Center, San Raffaele Scientific Institute, Via Olgettina 60, I-20132 Milan, Italy
| | - Agnese Secondo
- Division of Pharmacology, Department of Neuroscience, School of Medicine, University of Naples Federico II, Via Pansini 5, I-80131 Naples, Italy
| | - Eloise Mastrangelo
- National Research Council-Biophysics Institute (CNR-IBF), and Biosciences Department University of Milan, Via Celoria, 26, I-20133 Milan, Italy
| | - Giuseppe Pignataro
- Division of Pharmacology, Department of Neuroscience, School of Medicine, University of Naples Federico II, Via Pansini 5, I-80131 Naples, Italy
| | - Pierfausto Seneci
- Chemistry Department, University of Milan, Via Golgi 19, 20133 Milan, Italy
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Zhou G, Zha XM. GPR68 Contributes to Persistent Acidosis-Induced Activation of AGC Kinases and Tyrosine Phosphorylation in Organotypic Hippocampal Slices. Front Neurosci 2021; 15:692217. [PMID: 34113235 PMCID: PMC8185064 DOI: 10.3389/fnins.2021.692217] [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: 04/07/2021] [Accepted: 04/29/2021] [Indexed: 12/28/2022] Open
Abstract
Persistent acidosis occurs in ischemia and multiple neurological diseases. In previous studies, acidic stimulation leads to rapid increase in intracellular calcium in neurons. However, it remains largely unclear how a prolonged acidosis alters neuronal signaling. In our previous study, we found that GPR68-mediated PKC activities are protective against acidosis-induced injury in cortical slices. Here, we first asked whether the same principle holds true in organotypic hippocampal slices. Our data showed that 1-h pH 6 induced PKC phosphorylation in a GPR68-dependent manner. Go6983, a PKC inhibitor worsened acidosis-induced neuronal injury in wild type (WT) but had no effect in GPR68−/− slices. Next, to gain greater insights into acid signaling in brain tissue, we treated organotypic hippocampal slices with pH 6 for 1-h and performed a kinome profiling analysis by Western blot. Acidosis had little effect on cyclin-dependent kinase (CDK) or casein kinase 2 activity, two members of the CMGC family, or Ataxia telangiectasia mutated (ATM)/ATM and RAD3-related (ATR) activity, but reduced the phosphorylation of MAPK/CDK substrates. In contrast, acidosis induced the activation of CaMKIIα, PKA, and Akt. Besides these serine/threonine kinases, acidosis also induced tyrosine phosphorylation. Since GPR68 is widely expressed in brain neurons, we asked whether GPR68 contributes to acidosis-induced signaling. Deleting GPR68 had no effect on acidosis-induced CaMKII phosphorylation, attenuated that of phospho-Akt and phospho-PKA substrates, while abolishing acidosis-induced tyrosine phosphorylation. These data demonstrate that prolonged acidosis activates a network of signaling cascades, mediated by AGC kinases, CaMKII, and tyrosine kinases. GPR68 is the primary mediator for acidosis-induced activation of PKC and tyrosine phosphorylation, while both GPR68-dependent and -independent mechanisms contribute to the activation of PKA and Akt.
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Affiliation(s)
- Guokun Zhou
- Department of Physiology and Cell Biology, University of South Alabama College of Medicine, Mobile, AL, United States
| | - Xiang-Ming Zha
- Department of Physiology and Cell Biology, University of South Alabama College of Medicine, Mobile, AL, United States
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Zhu Y, Warrenfelt CIC, Flannery JC, Lindgren CA. Extracellular Protons Mediate Presynaptic Homeostatic Potentiation at the Mouse Neuromuscular Junction. Neuroscience 2021; 467:188-200. [PMID: 34215419 DOI: 10.1016/j.neuroscience.2021.01.036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 01/22/2021] [Accepted: 01/28/2021] [Indexed: 01/27/2023]
Abstract
At the vertebrate neuromuscular junction (NMJ), presynaptic homeostatic potentiation (PHP) refers to the upregulation of neurotransmitter release via an increase in quantal content (QC) when the postsynaptic nicotinic acetylcholine receptors (nAChRs) are partially blocked. The mechanism of PHP has not been completely worked out. In particular, the identity of the presumed retrograde signal is still a mystery. We investigated the role of acid-sensing ion channels (ASICs) and extracellular protons in mediating PHP at the mouse NMJ. We found that blocking AISCs using benzamil, psalmotoxin-1 (PcTx1), or mambalgin-3 (Mamb3) prevented PHP. Likewise, extracellular acidification from pH 7.4 to 7.2 triggered a significant, reversable increase in QC and this increase could be prevented by PcTx1. Interestingly, an acidic saline (pH 7.2) also precluded the subsequent induction of PHP. Using immunofluorescence we observed ASIC2a and ASIC1 subunits at the NMJ. Our results indicate that protons and ASIC channels are involved in activating PHP at the mouse NMJ. We speculate that the partial blockade of nAChRs leads to a modest decrease in the pH of the synaptic cleft (∼0.2 pH units) and this activates ASIC channels on the presynaptic nerve terminal.
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Affiliation(s)
- Yiyang Zhu
- Department of Biology, Grinnell College, Grinnell, IA 50112, USA
| | | | - Jill C Flannery
- Department of Biology, Grinnell College, Grinnell, IA 50112, USA
| | - Clark A Lindgren
- Department of Biology, Grinnell College, Grinnell, IA 50112, USA.
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Cheng S, Mao X, Lin X, Wehn A, Hu S, Mamrak U, Khalin I, Wostrack M, Ringel F, Plesnila N, Terpolilli NA. Acid-Ion Sensing Channel 1a Deletion Reduces Chronic Brain Damage and Neurological Deficits after Experimental Traumatic Brain Injury. J Neurotrauma 2021; 38:1572-1584. [PMID: 33779289 DOI: 10.1089/neu.2020.7568] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Traumatic brain injury (TBI) causes long-lasting neurodegeneration and cognitive impairments; however, the underlying mechanisms of these processes are not fully understood. Acid-sensing ion channels 1a (ASIC1a) are voltage-gated Na+- and Ca2+-channels shown to be involved in neuronal cell death; however, their role for chronic post-traumatic brain damage is largely unknown. To address this issue, we used ASIC1a-deficient mice and investigated their outcome up to 6 months after TBI. ASIC1a-deficient mice and their wild-type (WT) littermates were subjected to controlled cortical impact (CCI) or sham surgery. Brain water content was analyzed 24 h and behavioral outcome up to 6 months after CCI. Lesion volume was assessed longitudinally by magnetic resonance imaging and 6 months after injury by histology. Brain water content was significantly reduced in ASIC1a-/- animals compared to WT controls. Over time, ASIC1a-/- mice showed significantly reduced lesion volume and reduced hippocampal damage. This translated into improved cognitive function and reduced depression-like behavior. Microglial activation was significantly reduced in ASIC1a-/- mice. In conclusion, ASIC1a deficiency resulted in reduced edema formation acutely after TBI and less brain damage, functional impairments, and neuroinflammation up to 6 months after injury. Hence, ASIC1a seems to be involved in chronic neurodegeneration after TBI.
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Affiliation(s)
- Shiqi Cheng
- Institute for Stroke and Dementia Research, Munich University Hospital, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Xiang Mao
- Institute for Stroke and Dementia Research, Munich University Hospital, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Xiangjiang Lin
- Institute for Stroke and Dementia Research, Munich University Hospital, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Antonia Wehn
- Institute for Stroke and Dementia Research, Munich University Hospital, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Senbin Hu
- Institute for Stroke and Dementia Research, Munich University Hospital, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Uta Mamrak
- Institute for Stroke and Dementia Research, Munich University Hospital, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Igor Khalin
- Institute for Stroke and Dementia Research, Munich University Hospital, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Maria Wostrack
- Department of Neurosurgery, Technical University Munich, Munich, Germany
| | - Florian Ringel
- Department of Neurosurgery, University Medical Center Mainz, Mainz, Germany
| | - Nikolaus Plesnila
- Institute for Stroke and Dementia Research, Munich University Hospital, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Nicole A Terpolilli
- Institute for Stroke and Dementia Research, Munich University Hospital, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.,Department of Neurosurgery, Munich University Hospital, Munich, Germany
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Ruan N, Tribble J, Peterson AM, Jiang Q, Wang JQ, Chu XP. Acid-Sensing Ion Channels and Mechanosensation. Int J Mol Sci 2021; 22:ijms22094810. [PMID: 34062742 PMCID: PMC8125064 DOI: 10.3390/ijms22094810] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 04/29/2021] [Accepted: 04/30/2021] [Indexed: 12/16/2022] Open
Abstract
Acid-sensing ion channels (ASICs) are mainly proton-gated cation channels that are activated by pH drops and nonproton ligands. They are part of the degenerin/epithelial sodium channel superfamily due to their sodium permeability. Predominantly expressed in the central nervous system, ASICs are involved in synaptic plasticity, learning/memory, and fear conditioning. These channels have also been implicated in multiple disease conditions, including ischemic brain injury, multiple sclerosis, Alzheimer’s disease, and drug addiction. Recent research has illustrated the involvement of ASICs in mechanosensation. Mechanosensation is a form of signal transduction in which mechanical forces are converted into neuronal signals. Specific mechanosensitive functions have been elucidated in functional ASIC1a, ASIC1b, ASIC2a, and ASIC3. The implications of mechanosensation in ASICs indicate their subsequent involvement in functions such as maintaining blood pressure, modulating the gastrointestinal function, and bladder micturition, and contributing to nociception. The underlying mechanism of ASIC mechanosensation is the tether-gate model, which uses a gating-spring mechanism to activate ASIC responses. Further understanding of the mechanism of ASICs will help in treatments for ASIC-related pathologies. Along with the well-known chemosensitive functions of ASICs, emerging evidence has revealed that mechanosensitive functions of ASICs are important for maintaining homeostasis and contribute to various disease conditions.
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Neuhof A, Tian Y, Reska A, Falkenburger BH, Gründer S. Large Acid-Evoked Currents, Mediated by ASIC1a, Accompany Differentiation in Human Dopaminergic Neurons. Front Cell Neurosci 2021; 15:668008. [PMID: 33986647 PMCID: PMC8110905 DOI: 10.3389/fncel.2021.668008] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 04/06/2021] [Indexed: 12/21/2022] Open
Abstract
Acid-sensing ion channels (ASICs) are proton-gated Na+ channels. They contribute to synaptic transmission, neuronal differentiation and neurodegeneration. ASICs have been mainly characterized in neurons from mice or rats and our knowledge of their properties in human neurons is scarce. Here, we functionally characterized ASICs in differentiating LUHMES cells, a human mesencephalic cell line with characteristics of dopaminergic neurons. We find that LUHMES cells express functional ASICs, predominantly homomeric ASIC1a. Expression starts early during differentiation with a striking surge in current amplitude at days 4-6 of differentiation, a time point where-based on published data-LUHMES cells start expressing synaptic markers. Peak ASIC expression therefore coincides with a critical period of LUHMES cell differentiation. It was associated with increased excitability, but not paralleled by an increase in ASIC1 mRNA or protein. In differentiating as well as in terminally differentiated LUHMES cells, ASIC activation by slight acidification elicited large currents, action potentials and a rise in cytosolic Ca2+. Applying the ASIC pore blocker diminazene during differentiation reduced the length of neurites, consistent with the hypothesis that ASICs play a critical role in LUHMES cell differentiation. In summary, our study establishes LUHMES cells as a valuable model to study the role of ASICs for neuronal differentiation and potentially also cell death in a human cell line.
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Affiliation(s)
- Andreas Neuhof
- Department of Neurology, Institute of Physiology, RWTH Aachen University, Aachen, Germany.,Department of Neurology, RWTH Aachen University, Aachen, Germany
| | - Yuemin Tian
- Department of Neurology, Institute of Physiology, RWTH Aachen University, Aachen, Germany
| | - Anna Reska
- Department of Neurology, Institute of Physiology, RWTH Aachen University, Aachen, Germany
| | | | - Stefan Gründer
- Department of Neurology, Institute of Physiology, RWTH Aachen University, Aachen, Germany
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Citric Acid in Drug Formulations Causes Pain by Potentiating Acid-Sensing Ion Channel 1. J Neurosci 2021; 41:4596-4606. [PMID: 33888605 PMCID: PMC8260239 DOI: 10.1523/jneurosci.2087-20.2021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 12/08/2020] [Accepted: 04/10/2021] [Indexed: 11/21/2022] Open
Abstract
Pain at the injection site is a common complaint of patients receiving therapeutic formulations containing citric acid. Despite the widely acknowledged role of acid-sensing ion channels (ASICs) in acid-related perception, the specific ASIC subtype mediating pain caused by subcutaneous acid injection and the mechanism by which citrate affects this process are less clear. Here, male mice subjected to intraplantar acid injection responded by executing a withdrawal reflex, and this response was abolished by ASIC1 but not ASIC2 knockout. Although intraplantar injection of neutral citrate solution did not produce this response, intraplantar injection of acidic citrate solution produced a withdrawal reflex greater than that produced by acidity alone. Consistent with the behavioral data, neutral citrate failed to produce an electrophysiological response in HEK293 cells, which express ASIC1, but acidic citrate produced a whole-cell inward current greater than that produced by acidity alone. Saturating the intracellular solution with citrate had no effect on the potentiating effect of extracellular citrate, suggesting that citrate acted extracellularly to potentiate ASIC1. Moreover, exposure to citrate immediately before acid stimulation failed to potentiate ASIC1 currents, which ruled out the involvement of a metabotropic receptor gated by a citrate metabolite. Finally, removal of calcium ions from the extracellular solution mimicked the potentiating effect of citrate and prevented citrate from further potentiating ASIC1. Our data demonstrate that ASIC1 is necessary for the nociceptive response caused by subcutaneous acid infusion and that neutral citrate, despite not inducing ASIC1 currents or nociceptive behavior on its own, potentiates acid nociception by removing the inhibitory effect of extracellular calcium ions on ASIC1. SIGNIFICANCE STATEMENT Citric acid is a common ingredient used in pharmaceutical formulations. Despite the widespread clinical use of these formulations, it remains unclear how citric acid causes pain when injected into patients. We identified ASIC1 as the key receptor used to detect injection-site pain caused by acid, and we showed that neutral citrate does not stimulate ASIC1; instead, citrate substantially potentiates ASIC1 activation when injected simultaneously with acid. In addition, we demonstrated that citrate potentiates ASIC1 by removing the inhibitory action of calcium on the extracellular side of the receptor. Given that injection-site pain is the primary complaint of patients receiving citrate-containing medical products, our data provide mechanistic insight into a common medical complaint and suggest a means of avoiding injection pain.
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Sheng Y, Wu B, Leng T, Zhu L, Xiong Z. Acid-sensing ion channel 1 (ASIC1) mediates weak acid-induced migration of human malignant glioma cells. Am J Cancer Res 2021; 11:997-1008. [PMID: 33791169 PMCID: PMC7994151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 08/21/2020] [Indexed: 06/12/2023] Open
Abstract
Glioblastoma is the most aggressive and lethal tumor in the central nervous system in adult and has poor prognosis due to strong proliferation and aggressive invasion capacity. Acidic microenvironment is commonly observed in tumor tissues but the exact role of acidosis in the pathophysiology of glioblastoma and underlying mechanisms remain unclear. Acid-sensing ion channels (ASICs) are proton-gated cation channels activated by low extracellular pH. Recent studies have suggested that ASICs are involved in the pathogenesis of some tumors, such as lung cancer and breast cancer. But the effect of acidosis and activation of ASICs on malignant glioma of the central nervous system has not been reported. In this study, we investigated the expression of ASIC1 in human glioma cell lines (U87MG and A172) and its possible effect on the proliferation and migration of these cells. The results demonstrated that ASIC1 is functionally expressed in U87MG and A172 cells. Treatment with extracellular weak acid (pH 7.0) has no effect on the proliferation but increases the migration of the two cell lines. Application of PcTX1, a specific inhibitor of ASIC1a and ASIC1a/2b channels, or knocking down ASIC1 by siRNA, can abolish the effect of weak acid-induced cell migration. Together, our results indicate that ASIC1 mediates extracellular weak acid induced migration of human malignant glioma cells and may therefore serve as a therapeutic target for malignant glioma in human.
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Affiliation(s)
- Yulan Sheng
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Soochow UniversitySuzhou, China
- Department of Neurobiology, Neuroscience Institute, Morehouse School of MedicineAtlanta, Georgia, USA
| | - Baoming Wu
- Department of Neurobiology, Neuroscience Institute, Morehouse School of MedicineAtlanta, Georgia, USA
| | - Tiandong Leng
- Department of Neurobiology, Neuroscience Institute, Morehouse School of MedicineAtlanta, Georgia, USA
| | - Li Zhu
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Soochow UniversitySuzhou, China
| | - Zhigang Xiong
- Department of Neurobiology, Neuroscience Institute, Morehouse School of MedicineAtlanta, Georgia, USA
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40
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Gobetto MN, González-Inchauspe C, Uchitel OD. Histamine and Corticosterone Modulate Acid Sensing Ion Channels (ASICs) Dependent Long-term Potentiation at the Mouse Anterior Cingulate Cortex. Neuroscience 2021; 460:145-160. [PMID: 33493620 DOI: 10.1016/j.neuroscience.2021.01.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 12/23/2020] [Accepted: 01/12/2021] [Indexed: 11/30/2022]
Abstract
Increase in proton concentration [H+] or decrease in local and global extracellular pH occurs in both physiological and pathological conditions. Acid-sensing ion channels (ASICs), belonging to the ENaC/Deg superfamily, play an important role in signal transduction as proton sensor. ASICs and in particular ASIC1a (one of the six ASICs subunits) which is permeable to Ca2+, are involved in many physiological processes including synaptic plasticity and neurodegenerative diseases. Activity-dependent long-term potentiation (LTP) is a major type of long-lasting synaptic plasticity in the CNS, associated with learning, memory, development, fear and persistent pain. Neurons in the anterior cingulate cortex (ACC) play critical roles in pain perception and chronic pain and express ASIC1a channels. During synaptic transmission, acidification of the synaptic cleft presumably due to the co-release of neurotransmitter and H+ from synaptic vesicles activates postsynaptic ASIC1a channels in ACC of mice. This generates ASIC1a synaptic currents that add to the glutamatergic excitatory postsynaptic currents (EPSCs). Here we report that modulators like histamine and corticosterone, acting through ASIC1a regulate synaptic plasticity, reducing the threshold for LTP induction of glutamatergic EPSCs. Our findings suggest a new role for ASIC1a mediating the neuromodulator action of histamine and corticosterone regulating specific forms of synaptic plasticity in the mouse ACC.
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Affiliation(s)
- María Natalia Gobetto
- Instituto de Fisiología, Biología molecular y Neurociencias (IFIBYNE) CONICET, Departamento de Fisiología, Biología Molecular y Celular "Dr. Héctor Maldonado", Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, C1428EGA Ciudad Autónoma de Buenos Aires, Argentina
| | - Carlota González-Inchauspe
- Instituto de Fisiología, Biología molecular y Neurociencias (IFIBYNE) CONICET, Departamento de Fisiología, Biología Molecular y Celular "Dr. Héctor Maldonado", Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, C1428EGA Ciudad Autónoma de Buenos Aires, Argentina
| | - Osvaldo D Uchitel
- Instituto de Fisiología, Biología molecular y Neurociencias (IFIBYNE) CONICET, Departamento de Fisiología, Biología Molecular y Celular "Dr. Héctor Maldonado", Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, C1428EGA Ciudad Autónoma de Buenos Aires, Argentina.
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DEG/ENaC Ion Channels in the Function of the Nervous System: From Worm to Man. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1349:165-192. [DOI: 10.1007/978-981-16-4254-8_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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42
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Liu X, Sambath K, Hutnik L, Du J, Belfield KD, Zhang Y. Activating Acid-Sensing Ion Channels with Photoacid Generators. CHEMPHOTOCHEM 2020; 4:5337-5340. [PMID: 36090950 PMCID: PMC9455902 DOI: 10.1002/cptc.202000154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Indexed: 09/05/2024]
Abstract
Acid-sensing ion channels (ASICs), present in both central and peripheral neurons, respond to changes in extracellular protons. They play important roles in many symptoms and diseases, such as pain, ischemic stroke and neurodegenerative diseases. Herein, we report a novel approach to activate ASICs with the precision of light using organic photoacid generators (PAGs), which are molecules that release H+ upon light illumination, and have been recently used in biomedical studies. The PAGs showed low toxicity in dark conditions. Under LED light illumination, ASICs activation and consequent calcium ion influx was monitored and analysed by fluorescence microscopy, and showed a strong light-dependent response. This approach allows the activation of ASICs with the precision of light, and may be valuable to help better elucidate the molecular mechanism of ASICs and unveil their roles in physiology, pathophysiology, and behaviour.
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Affiliation(s)
- Xinglei Liu
- Department of Chemistry and Environmental Science, College of Science and Liberal Arts, New Jersey Institute of Technology, 323 Martin Luther King, Jr. Blvd. Newark NJ 07102 (USA)
| | - Karthik Sambath
- Department of Chemistry and Environmental Science, College of Science and Liberal Arts, New Jersey Institute of Technology, 323 Martin Luther King, Jr. Blvd. Newark NJ 07102 (USA)
| | - Lauren Hutnik
- Department of Chemistry and Environmental Science, College of Science and Liberal Arts, New Jersey Institute of Technology, 323 Martin Luther King, Jr. Blvd. Newark NJ 07102 (USA)
| | - Jianyang Du
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, 855 Monroe Avenue, Memphis TN 38163 (USA)
| | - Kevin D Belfield
- Department of Chemistry and Environmental Science, College of Science and Liberal Arts, New Jersey Institute of Technology, 323 Martin Luther King, Jr. Blvd. Newark NJ 07102 (USA)
| | - Yuanwei Zhang
- Department of Chemistry and Environmental Science, College of Science and Liberal Arts, New Jersey Institute of Technology, 323 Martin Luther King, Jr. Blvd. Newark NJ 07102 (USA)
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Bhusal A, Rahman MH, Lee WH, Lee IK, Suk K. Satellite glia as a critical component of diabetic neuropathy: Role of lipocalin-2 and pyruvate dehydrogenase kinase-2 axis in the dorsal root ganglion. Glia 2020; 69:971-996. [PMID: 33251681 DOI: 10.1002/glia.23942] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 11/18/2020] [Accepted: 11/18/2020] [Indexed: 12/12/2022]
Abstract
Diabetic peripheral neuropathy (DPN) is a common complication of uncontrolled diabetes. The pathogenesis of DPN is associated with chronic inflammation in dorsal root ganglion (DRG), eventually causing structural and functional changes. Studies on DPN have primarily focused on neuronal component, and there is limited knowledge about the role of satellite glial cells (SGCs), although they completely enclose neuronal soma in DRG. Lipocalin-2 (LCN2) is a pro-inflammatory acute-phase protein found in high levels in diverse neuroinflammatory and metabolic disorders. In diabetic DRG, the expression of LCN2 was increased exclusively in the SGCs. This upregulation of LCN2 in SGCs correlated with increased inflammatory responses in DRG and sciatic nerve. Furthermore, diabetes-induced inflammation and morphological changes in DRG, as well as sciatic nerve, were attenuated in Lcn2 knockout (KO) mice. Lcn2 gene ablation also ameliorated neuropathy phenotype as determined by nerve conduction velocity and intraepidermal nerve fiber density. Mechanistically, studies using specific gene KO mice, adenovirus-mediated gene overexpression strategy, and primary cultures of DRG SGCs and neurons have demonstrated that LCN2 enhances the expression of mitochondrial gate-keeping regulator pyruvate dehydrogenase kinase-2 (PDK2) through PPARβ/δ, thereby inhibiting pyruvate dehydrogenase activity and increasing production of glycolytic end product lactic acid in DRG SGCs and neurons of diabetic mice. Collectively, our findings reveal a crucial role of glial LCN2-PPARβ/δ-PDK2-lactic acid axis in progression of DPN. Our results establish a link between pro-inflammatory LCN2 and glycolytic PDK2 in DRG SGCs and neurons and propose a novel glia-based mechanism and drug target for therapy of DPN. MAIN POINTS: Diabetes upregulates LCN2 in satellite glia, which in turn increases pyruvate dehydrogenase kinase-2 (PDK2) expression and lactic acid production in dorsal root ganglia (DRG). Glial LCN2-PDK2-lactic acid axis in DRG plays a crucial role in the pathogenesis of diabetic neuropathy.
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Affiliation(s)
- Anup Bhusal
- Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.,BK21 Plus KNU Biomedical Convergence Program, Department of Biomedical Sciences, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Md Habibur Rahman
- Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.,BK21 Plus KNU Biomedical Convergence Program, Department of Biomedical Sciences, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.,Brain Science and Engineering Institute, Kyungpook National University, Daegu, Republic of Korea
| | - Won-Ha Lee
- School of Life Sciences, Brain Korea 21 Plus/Kyungpook National University Creative BioResearch Group, Kyungpook National University, Daegu, Republic of Korea
| | - In-Kyu Lee
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea.,Research Institute of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea
| | - Kyoungho Suk
- Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.,BK21 Plus KNU Biomedical Convergence Program, Department of Biomedical Sciences, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.,Brain Science and Engineering Institute, Kyungpook National University, Daegu, Republic of Korea
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44
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Herzig V, Cristofori-Armstrong B, Israel MR, Nixon SA, Vetter I, King GF. Animal toxins - Nature's evolutionary-refined toolkit for basic research and drug discovery. Biochem Pharmacol 2020; 181:114096. [PMID: 32535105 PMCID: PMC7290223 DOI: 10.1016/j.bcp.2020.114096] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 06/06/2020] [Accepted: 06/09/2020] [Indexed: 12/27/2022]
Abstract
Venomous animals have evolved toxins that interfere with specific components of their victim's core physiological systems, thereby causing biological dysfunction that aids in prey capture, defense against predators, or other roles such as intraspecific competition. Many animal lineages evolved venom systems independently, highlighting the success of this strategy. Over the course of evolution, toxins with exceptional specificity and high potency for their intended molecular targets have prevailed, making venoms an invaluable and almost inexhaustible source of bioactive molecules, some of which have found use as pharmacological tools, human therapeutics, and bioinsecticides. Current biomedically-focused research on venoms is directed towards their use in delineating the physiological role of toxin molecular targets such as ion channels and receptors, studying or treating human diseases, targeting vectors of human diseases, and treating microbial and parasitic infections. We provide examples of each of these areas of venom research, highlighting the potential that venom molecules hold for basic research and drug development.
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Affiliation(s)
- Volker Herzig
- School of Science & Engineering, University of the Sunshine Coast, Sippy Downs, QLD, Australia; Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD, Australia.
| | | | - Mathilde R Israel
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD, Australia
| | - Samantha A Nixon
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD, Australia
| | - Irina Vetter
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD, Australia
| | - Glenn F King
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD, Australia.
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45
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Wang K, Kretschmannova K, Prévide RM, Smiljanic K, Chen Q, Fletcher PA, Sherman A, Stojilkovic SS. Cell-Type-Specific Expression Pattern of Proton-Sensing Receptors and Channels in Pituitary Gland. Biophys J 2020; 119:2335-2348. [PMID: 33098866 DOI: 10.1016/j.bpj.2020.10.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 06/29/2020] [Accepted: 10/15/2020] [Indexed: 12/14/2022] Open
Abstract
In mammalian cells, extracellular protons act as orthosteric and allosteric ligands for multiple receptors and channels. The aim of this study is to identify proton sensors in the rat pituitary gland. qRT-PCR analysis indicated the expression of G-protein-coupled receptor 68 gene (Gpr68) and acid-sensing ion channel (ASIC) genes Asic1, Asic2, and Asic4 in anterior pituitary cells and Asic1 and Asic2 in immortalized GH3 pituitary cells. Asic1a and Asic2b were the dominant splice isoforms. Single anterior pituitary cell RNA sequencing and immunocytochemical analysis showed that nonexcitable folliculostellate cells express GPR68 gene and protein, whereas excitable secretory cells express ASIC genes and proteins. Asic1 was detected in all secretory cell types, Asic2 in gonadotrophs, thyrotrophs, and somatotrophs, and Asic4 in lactotrophs. Extracellular acidification activated two types of currents in a concentration-dependent manner: a fast-developing, desensitizing current with an estimated EC50-value of pH 6.7 and a slow-developing, non-desensitizing current that required a higher proton concentration for activation. The desensitizing current was abolished by removal of bath sodium and application of amiloride, a blocker of ASIC channels, whereas the non-desensitizing current was amiloride insensitive and voltage dependent. Activation of both currents increased the excitability of secretory pituitary cells, consistent with their potential physiological relevance in control of voltage-gated calcium influx and calcium-dependent cellular functions.
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Affiliation(s)
- Kai Wang
- Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland
| | - Karla Kretschmannova
- Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland
| | - Rafael M Prévide
- Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland
| | - Kosara Smiljanic
- Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland
| | - Qing Chen
- Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland
| | - Patrick A Fletcher
- Laboratory of Biological Modeling, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Arthur Sherman
- Laboratory of Biological Modeling, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Stanko S Stojilkovic
- Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland.
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46
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Drug development in targeting ion channels for brain edema. Acta Pharmacol Sin 2020; 41:1272-1288. [PMID: 32855530 PMCID: PMC7609292 DOI: 10.1038/s41401-020-00503-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 08/02/2020] [Indexed: 12/18/2022] Open
Abstract
Cerebral edema is a pathological hallmark of various central nervous system (CNS) insults, including traumatic brain injury (TBI) and excitotoxic injury such as stroke. Due to the rigidity of the skull, edema-induced increase of intracranial fluid significantly complicates severe CNS injuries by raising intracranial pressure and compromising perfusion. Mortality due to cerebral edema is high. With mortality rates up to 80% in severe cases of stroke, it is the leading cause of death within the first week. Similarly, cerebral edema is devastating for patients of TBI, accounting for up to 50% mortality. Currently, the available treatments for cerebral edema include hypothermia, osmotherapy, and surgery. However, these treatments only address the symptoms and often elicit adverse side effects, potentially in part due to non-specificity. There is an urgent need to identify effective pharmacological treatments for cerebral edema. Currently, ion channels represent the third-largest target class for drug development, but their roles in cerebral edema remain ill-defined. The present review aims to provide an overview of the proposed roles of ion channels and transporters (including aquaporins, SUR1-TRPM4, chloride channels, glucose transporters, and proton-sensitive channels) in mediating cerebral edema in acute ischemic stroke and TBI. We also focus on the pharmacological inhibitors for each target and potential therapeutic strategies that may be further pursued for the treatment of cerebral edema.
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47
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Histidine Residues Are Responsible for Bidirectional Effects of Zinc on Acid-Sensing Ion Channel 1a/3 Heteromeric Channels. Biomolecules 2020; 10:biom10091264. [PMID: 32887365 PMCID: PMC7565092 DOI: 10.3390/biom10091264] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/26/2020] [Accepted: 08/31/2020] [Indexed: 12/16/2022] Open
Abstract
Acid-sensing ion channel (ASIC) subunits 1a and 3 are highly expressed in central and peripheral sensory neurons, respectively. Endogenous biomolecule zinc plays a critical role in physiological and pathophysiological conditions. Here, we found that currents recorded from heterologously expressed ASIC1a/3 channels using the whole-cell patch-clamp technique were regulated by zinc with dual effects. Co-application of zinc dose-dependently potentiated both peak amplitude and the sustained component of heteromeric ASIC1a/3 currents; pretreatment with zinc between 3 to 100 µM exerted the same potentiation as co-application. However, pretreatment with zinc induced a significant inhibition of heteromeric ASIC1a/3 channels when zinc concentrations were over 250 µM. The potentiation of heteromeric ASIC1a/3 channels by zinc was pH dependent, as zinc shifted the pH dependence of ASIC1a/3 currents from a pH50 of 6.54 to 6.77; whereas the inhibition of ASIC1a/3 currents by zinc was also pH dependent. Furthermore, we systematically mutated histidine residues in the extracellular domain of ASIC1a or ASIC3 and found that histidine residues 72 and 73 in both ASIC1a and ASIC3, and histidine residue 83 in the ASIC3 were responsible for bidirectional effects on heteromeric ASIC1a/3 channels by zinc. These findings suggest that histidine residues in the extracellular domain of heteromeric ASIC1a/3 channels are critical for zinc-mediated effects.
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48
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Bychkov M, Shulepko M, Osmakov D, Andreev Y, Sudarikova A, Vasileva V, Pavlyukov MS, Latyshev YA, Potapov AA, Kirpichnikov M, Shenkarev ZO, Lyukmanova E. Mambalgin-2 Induces Cell Cycle Arrest and Apoptosis in Glioma Cells via Interaction with ASIC1a. Cancers (Basel) 2020; 12:E1837. [PMID: 32650495 PMCID: PMC7408772 DOI: 10.3390/cancers12071837] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/27/2020] [Accepted: 07/02/2020] [Indexed: 02/06/2023] Open
Abstract
Gliomas are fast growing and highly invasive brain tumors, characterized by tumor microenvironment acidification that drives glioma cell growth and migration. Channels containing Acid-sensing Ion Channel 1a subunit (ASIC1a) mediate amiloride-sensitive cation influx in late stage glioma cells, but not in normal astrocytes. Thus, selective targeting of ASIC1a can be a perspective strategy for glioma treatment. Here, ASIC1a expression in U251 MG and A172 glioma cells, but not in normal astrocytes, was demonstrated. Recombinant analog of mambalgin-2 from black mamba Dendroaspis polylepis inhibited amiloride-sensitive currents at ASIC1a both in Xenopus laevis oocytes and in U251 MG cells, while its mutants with impaired activity towards this channel did not. Mambalgin-2 inhibited U251 MG and A172 glioma cells growth with EC50 in the nanomolar range without affecting the proliferation of normal astrocytes. Notably, mambalgin-2 mutants did not affect glioma cell proliferation, pointing on ASIC1a as the main molecular target of mambalgin-2 in U251 MG and A172 cells. Mambalgin-2 induced a cell cycle arrest, inhibited Cyclin D1 and cyclin-dependent kinases (CDK) phosphorylation and caused apoptosis in U251 MG and A172 cells. Moreover, mambalgin-2 inhibited the growth of low-passage primary cells from a patient with glioblastoma. Altogether, our data point to mambalgin-2 as a useful hit for the development of new drugs for glioma treatment.
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Affiliation(s)
- Maxim Bychkov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (M.B.); (M.S.); (D.O.); (Y.A.); (M.S.P.); (M.K.); (Z.O.S.)
| | - Mikhail Shulepko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (M.B.); (M.S.); (D.O.); (Y.A.); (M.S.P.); (M.K.); (Z.O.S.)
| | - Dmitry Osmakov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (M.B.); (M.S.); (D.O.); (Y.A.); (M.S.P.); (M.K.); (Z.O.S.)
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| | - Yaroslav Andreev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (M.B.); (M.S.); (D.O.); (Y.A.); (M.S.P.); (M.K.); (Z.O.S.)
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| | - Anastasia Sudarikova
- Institute of Cytology, Russian Academy of Science, 194064 St-Petersburg, Russia; (A.S.); (V.V.)
| | - Valeria Vasileva
- Institute of Cytology, Russian Academy of Science, 194064 St-Petersburg, Russia; (A.S.); (V.V.)
| | - Marat S. Pavlyukov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (M.B.); (M.S.); (D.O.); (Y.A.); (M.S.P.); (M.K.); (Z.O.S.)
| | - Yaroslav A. Latyshev
- Federal State Autonomous Institution, N.N. Burdenko National Medical Research Center of Neurosurgery, 125047 Moscow, Russia; (Y.A.L.); (A.A.P.)
| | - Alexander A. Potapov
- Federal State Autonomous Institution, N.N. Burdenko National Medical Research Center of Neurosurgery, 125047 Moscow, Russia; (Y.A.L.); (A.A.P.)
| | - Mikhail Kirpichnikov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (M.B.); (M.S.); (D.O.); (Y.A.); (M.S.P.); (M.K.); (Z.O.S.)
- Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Zakhar O. Shenkarev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (M.B.); (M.S.); (D.O.); (Y.A.); (M.S.P.); (M.K.); (Z.O.S.)
- Phystech School of Biological and Medical Physics, Moscow Institute of Physics and Technology (State University), 141701 Dolgoprudny, Moscow Region, Russia
| | - Ekaterina Lyukmanova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (M.B.); (M.S.); (D.O.); (Y.A.); (M.S.P.); (M.K.); (Z.O.S.)
- Phystech School of Biological and Medical Physics, Moscow Institute of Physics and Technology (State University), 141701 Dolgoprudny, Moscow Region, Russia
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49
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Osmakov DI, Khasanov TA, Andreev YA, Lyukmanova EN, Kozlov SA. Animal, Herb, and Microbial Toxins for Structural and Pharmacological Study of Acid-Sensing Ion Channels. Front Pharmacol 2020; 11:991. [PMID: 32733241 PMCID: PMC7360831 DOI: 10.3389/fphar.2020.00991] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 06/19/2020] [Indexed: 12/22/2022] Open
Abstract
Acid-sensing ion channels (ASICs) are of the most sensitive molecular sensors of extracellular pH change in mammals. Six isoforms of these channels are widely represented in membranes of neuronal and non-neuronal cells, where these molecules are involved in different important regulatory functions, such as synaptic plasticity, learning, memory, and nociception, as well as in various pathological states. Structural and functional studies of both wild-type and mutant ASICs are essential for human care and medicine for the efficient treatment of socially significant diseases and ensure a comfortable standard of life. Ligands of ASICs serve as indispensable tools for these studies. Such bioactive compounds can be synthesized artificially. However, to date, the search for such molecules has been most effective amongst natural sources, such as animal venoms or plants and microbial extracts. In this review, we provide a detailed and comprehensive structural and functional description of natural compounds acting on ASICs, as well as the latest information on structural aspects of their interaction with the channels. Many of the examples provided in the review demonstrate the undoubted fundamental and practical successes of using natural toxins. Without toxins, it would not be possible to obtain data on the mechanisms of ASICs' functioning, provide detailed study of their pharmacological properties, or assess the contribution of the channels to development of different pathologies. The selectivity to different isoforms and variety in the channel modulation mode allow for the appraisal of prospective candidates for the development of new drugs.
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Affiliation(s)
- Dmitry I Osmakov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia
| | - Timur A Khasanov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
| | - Yaroslav A Andreev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia
| | - Ekaterina N Lyukmanova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
| | - Sergey A Kozlov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
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50
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Papalampropoulou-Tsiridou M, Labrecque S, Godin AG, De Koninck Y, Wang F. Differential Expression of Acid - Sensing Ion Channels in Mouse Primary Afferents in Naïve and Injured Conditions. Front Cell Neurosci 2020; 14:103. [PMID: 32508593 PMCID: PMC7248332 DOI: 10.3389/fncel.2020.00103] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 04/03/2020] [Indexed: 12/15/2022] Open
Abstract
Injury and inflammation cause tissue acidosis, which is a common feature of various painful conditions. Acid-Sensing Ion channels (ASICs) are amongst the main excitatory channels activated by extracellular protons and expressed in the nervous system. Six transcripts of ASIC subunits including ASIC1a, ASIC1b, ASIC2a, ASIC2b, ASIC3, and ASIC4 are encoded by four genes (Asic1–4) and have been identified in rodents. Most ASIC subunits are present at substantial levels in primary sensory neurons of dorsal root ganglia (DRG) except for ASIC4. However, their expression pattern in DRG neurons remains largely unclear, mainly due to the lack of antibodies with appropriate specificity. In this study, we examined in detail the expression pattern of ASIC1-3 subunits, including splice variants, in different populations of DRG neurons in adult mice using an in situ hybridization technique (RNAscope) with high sensitivity and specificity. We found that in naïve condition, all five subunits examined were expressed in the majority of myelinated, NF200-immunoreactive, DRG neurons (NF200+). However, ASIC subunits showed a very different expression pattern among non-myelinated DRG neuronal subpopulations: ASIC1 and ASIC3 were only expressed in CGRP-immunoreactive neurons (CGRP+), ASIC2a was mostly expressed in the majority of IB4-binding neurons (IB4+), while ASIC2b was expressed in almost all non-myelinated DRG neurons. We also found that at least half of sensory neurons expressed multiple types of ASIC subunits, indicating prevalence of heteromeric channels. In mice with peripheral nerve injury, the expression level of ASIC1a and ASIC1b in L4 DRG and ASIC3 in L5 DRG were altered in CGRP+ neurons, but not in IB4+ neurons. Furthermore, the pattern of change varied among DRGs depending on their segmental level, which pointed to differential regulatory mechanisms between afferent types and anatomical location. The distinct expression pattern of ASIC transcripts in naïve condition, and the differential regulation of ASIC subunits after peripheral nerve injury, suggest that ASIC subunits are involved in separate sensory modalities.
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Affiliation(s)
- Melina Papalampropoulou-Tsiridou
- CERVO Brain Research Centre, Québec Mental Health Institute, Québec, QC, Canada.,Graduate Program in Neuroscience, Université Laval, Québec, QC, Canada
| | - Simon Labrecque
- CERVO Brain Research Centre, Québec Mental Health Institute, Québec, QC, Canada
| | - Antoine G Godin
- CERVO Brain Research Centre, Québec Mental Health Institute, Québec, QC, Canada.,Graduate Program in Neuroscience, Université Laval, Québec, QC, Canada.,Department of Psychiatry and Neuroscience, Université Laval, Québec, QC, Canada
| | - Yves De Koninck
- CERVO Brain Research Centre, Québec Mental Health Institute, Québec, QC, Canada.,Graduate Program in Neuroscience, Université Laval, Québec, QC, Canada.,Department of Psychiatry and Neuroscience, Université Laval, Québec, QC, Canada
| | - Feng Wang
- CERVO Brain Research Centre, Québec Mental Health Institute, Québec, QC, Canada
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