1
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Foster VS, Saez N, King GF, Rank MM. Acute inhibition of acid sensing ion channel 1a after spinal cord injury selectively affects excitatory synaptic transmission, but not intrinsic membrane properties, in deep dorsal horn interneurons. PLoS One 2023; 18:e0289053. [PMID: 37939057 PMCID: PMC10631665 DOI: 10.1371/journal.pone.0289053] [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: 01/11/2023] [Accepted: 07/10/2023] [Indexed: 11/10/2023] Open
Abstract
Following a spinal cord injury (SCI), secondary damage mechanisms are triggered that cause inflammation and cell death. A key component of this secondary damage is a reduction in local blood flow that initiates a well-characterised ischemic cascade. Downstream hypoxia and acidosis activate acid sensing ion channel 1a (ASIC1a) to trigger cell death. We recently showed that administration of a potent venom-derived inhibitor of ASIC1a, Hi1a, leads to tissue sparing and improved functional recovery when delivered up to 8 h after ischemic stroke. Here, we use whole-cell patch-clamp electrophysiology in a spinal cord slice preparation to assess the effect of acute ASIC1a inhibition, via a single dose of Hi1a, on intrinsic membrane properties and excitatory synaptic transmission long-term after a spinal cord hemisection injury. We focus on a population of interneurons (INs) in the deep dorsal horn (DDH) that play a key role in relaying sensory information to downstream motoneurons. DDH INs in mice treated with Hi1a 1 h after a spinal cord hemisection showed no change in active or passive intrinsic membrane properties measured 4 weeks after SCI. DDH INs, however, exhibit significant changes in the kinetics of spontaneous excitatory postsynaptic currents after a single dose of Hi1a, when compared to naive animals (unlike SCI mice). Our data suggest that acute ASIC1a inhibition exerts selective effects on excitatory synaptic transmission in DDH INs after SCI via specific ligand-gated receptor channels, and has no effect on other voltage-activated channels long-term after SCI.
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Affiliation(s)
- Victoria S. Foster
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, Queensland, Australia
- St George’s, University of London, Medical School, London, England
| | - Natalie Saez
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, Queensland, Australia
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, St Lucia, Queensland, Australia
| | - Glenn F. King
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, Queensland, Australia
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, St Lucia, Queensland, Australia
| | - Michelle M. Rank
- Department of Anatomy and Physiology, School of Biomedical Science, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, Victoria, Australia
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2
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Evlanenkov KK, Zhigulin AS, Tikhonov DB. Possible Compensatory Role of ASICs in Glutamatergic Synapses. Int J Mol Sci 2023; 24:12974. [PMID: 37629153 PMCID: PMC10455551 DOI: 10.3390/ijms241612974] [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: 08/01/2023] [Revised: 08/17/2023] [Accepted: 08/18/2023] [Indexed: 08/27/2023] Open
Abstract
Proton-gated channels of the ASIC family are widely distributed in central neurons, suggesting their role in common neurophysiological functions. They are involved in glutamatergic neurotransmission and synaptic plasticity; however, the exact function of these channels remains unclear. One problem is that acidification of the synaptic cleft due to the acidic content of synaptic vesicles has opposite effects on ionotropic glutamate receptors and ASICs. Thus, the pH values required to activate ASICs strongly inhibit AMPA receptors and almost completely inhibit NMDA receptors. This, in turn, suggests that ASICs can provide compensation for post-synaptic responses in the case of significant acidifications. We tested this hypothesis by patch-clamp recordings of rat brain neuron responses to acidifications and glutamate receptor agonists at different pH values. Hippocampal pyramidal neurons have much lower ASICs than glutamate receptor responses, whereas striatal interneurons show the opposite ratio. Cortical pyramidal neurons and hippocampal interneurons show similar amplitudes in their responses to acidification and glutamate. Consequently, the total response to glutamate agonists at different pH levels remains rather stable up to pH 6.2. Besides these pH effects, the relationship between the responses mediated by glutamate receptors and ASICs depends on the presence of Mg2+ and the membrane voltage. Together, these factors create a complex picture that provides a framework for understanding the role of ASICs in synaptic transmission and synaptic plasticity.
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Affiliation(s)
| | | | - Denis B. Tikhonov
- Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, St. Petersburg 194223, Russia; (K.K.E.); (A.S.Z.)
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3
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Cherninskyi A, Storozhuk M, Maximyuk O, Kulyk V, Krishtal O. Triggering of Major Brain Disorders by Protons and ATP: The Role of ASICs and P2X Receptors. Neurosci Bull 2023; 39:845-862. [PMID: 36445556 PMCID: PMC9707125 DOI: 10.1007/s12264-022-00986-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 08/14/2022] [Indexed: 11/30/2022] Open
Abstract
Adenosine triphosphate (ATP) is well-known as a universal source of energy in living cells. Less known is that this molecule has a variety of important signaling functions: it activates a variety of specific metabotropic (P2Y) and ionotropic (P2X) receptors in neuronal and non-neuronal cell membranes. So, a wide variety of signaling functions well fits the ubiquitous presence of ATP in the tissues. Even more ubiquitous are protons. Apart from the unspecific interaction of protons with any protein, many physiological processes are affected by protons acting on specific ionotropic receptors-acid-sensing ion channels (ASICs). Both protons (acidification) and ATP are locally elevated in various pathological states. Using these fundamentally important molecules as agonists, ASICs and P2X receptors signal a variety of major brain pathologies. Here we briefly outline the physiological roles of ASICs and P2X receptors, focusing on the brain pathologies involving these receptors.
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Affiliation(s)
- Andrii Cherninskyi
- Bogomoletz Institute of Physiology of National Academy of Sciences of Ukraine, Kyiv, 01024, Ukraine.
| | - Maksim Storozhuk
- Bogomoletz Institute of Physiology of National Academy of Sciences of Ukraine, Kyiv, 01024, Ukraine
| | - Oleksandr Maximyuk
- Bogomoletz Institute of Physiology of National Academy of Sciences of Ukraine, Kyiv, 01024, Ukraine
| | - Vyacheslav Kulyk
- Bogomoletz Institute of Physiology of National Academy of Sciences of Ukraine, Kyiv, 01024, Ukraine
| | - Oleg Krishtal
- Bogomoletz Institute of Physiology of National Academy of Sciences of Ukraine, Kyiv, 01024, Ukraine
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4
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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: 0] [Impact Index Per Article: 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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5
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Zhu Y, Hu X, Wang L, Zhang J, Pan X, Li Y, Cao R, Li B, Lin H, Wang Y, Zuo L, Huang Y. Recent Advances in Acid-sensitive Ion Channels in Central Nervous System Diseases. Curr Pharm Des 2022; 28:1406-1411. [PMID: 35466865 DOI: 10.2174/1381612828666220422084159] [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: 12/13/2021] [Accepted: 02/24/2022] [Indexed: 11/22/2022]
Abstract
Acid-sensitive ion channels (ASICs) are cationic channels activated by extracellular protons and widely distributed in the nervous system of mammals. It belongs to the ENaC/DEG family and has four coding genes: ASIC1, ASIC2, ASIC3, and ASIC4, which encode eight subunit proteins: ASIC1a, ASIC1b, ASIC1b2, ASIC2a, ASIC2b, ASIC3, ASIC4, and ASIC5. Different subtypes of ASICs have different distributions in the central nervous system, and they play an important role in various physiological and pathological processes of the central nervous system, including synaptic plasticity, anxiety disorders, fear conditioning, depression-related behavior, epilepsy, Alzheimer's disease, Parkinson's disease, Huntington's disease, multiple sclerosis, malignant Glioma, pain, and others. This paper reviewed the recent studies of ASICs on the central nervous system to improve the understanding of ASICs' physiological functions and pathological effects. This article also provides a reference for studying the molecular mechanisms and therapeutic measures of nervous system-related diseases.
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Affiliation(s)
- Yueqin Zhu
- Department of Pharmacy, West Branch of The First Affiliated Hospital of University of Science and Technology of China (Anhui Provincial Cancer Hospital), Hefei, 230031, China
| | - Xiaojie Hu
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Lili Wang
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Jin Zhang
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Xuesheng Pan
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Yangyang Li
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Rui Cao
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Bowen Li
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Huimin Lin
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Yanan Wang
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Longquan Zuo
- Department of Pharmacy, Hospital of Armed Police of Anhui Province, Hefei 230061, Anhui, China
| | - Yan Huang
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
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6
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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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7
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Koffman EE, Kruse CM, Singh K, Naghavi FS, Curtis MA, Egbo J, Houdi M, Lin B, Lu H, Debiec J, Du J. Acid-sensing ion channel 1a regulates the specificity of reconsolidation of conditioned threat responses. JCI Insight 2022; 7:155341. [PMID: 35025766 PMCID: PMC8876458 DOI: 10.1172/jci.insight.155341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 01/12/2022] [Indexed: 11/26/2022] Open
Abstract
Recent research on altering threat memory has focused on a reconsolidation window. During reconsolidation, threat memories are retrieved and become labile. Reconsolidation of distinct threat memories is synapse dependent, whereas the underlying regulatory mechanism of the specificity of reconsolidation is poorly understood. We designed a unique behavioral paradigm in which a distinct threat memory can be retrieved through the associated conditioned stimulus. In addition, we proposed a regulatory mechanism by which the activation of acid-sensing ion channels (ASICs) strengthens the distinct memory trace associated with the memory reconsolidation to determine its specificity. The activation of ASICs by CO2 inhalation, when paired with memory retrieval, triggers the reactivation of the distinct memory trace, resulting in greater memory lability. ASICs potentiate the memory trace by altering the amygdala-dependent synaptic transmission and plasticity at selectively targeted synapses. Our results suggest that inhaling CO2 during the retrieval event increases the lability of a threat memory through a synapse-specific reconsolidation process.
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Affiliation(s)
- Erin E Koffman
- Department of Biological Sciences, The University of Toledo, Toledo, United States of America
| | - Charles M Kruse
- Department of Biological Sciences, The University of Toledo, Toledo, United States of America
| | - Kritika Singh
- Department of Biological Sciences, The University of Toledo, Toledo, United States of America
| | - Farzaneh Sadat Naghavi
- Department of Biological Sciences, The University of Toledo, Toledo, United States of America
| | - Melissa A Curtis
- Department of Biological Sciences, The University of Toledo, Toledo, United States of America
| | - Jennifer Egbo
- Department of Biological Sciences, The University of Toledo, Toledo, United States of America
| | - Mark Houdi
- Department of Biological Sciences, The University of Toledo, Toledo, United States of America
| | - Boren Lin
- Department of Biological Sciences, The University of Toledo, Toledo, United States of America
| | - Hui Lu
- Department of Pharmacology and Physiology, George Washington University, Washington, DC, United States of America
| | - Jacek Debiec
- Department of Psychiatry, The University of Michigan Medical School, Ann Arbor, United States of America
| | - Jianyang Du
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, United States of America
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8
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Mango D, Nisticò R. Neurodegenerative Disease: What Potential Therapeutic Role of Acid-Sensing Ion Channels? Front Cell Neurosci 2021; 15:730641. [PMID: 34690702 PMCID: PMC8531221 DOI: 10.3389/fncel.2021.730641] [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: 06/25/2021] [Accepted: 09/15/2021] [Indexed: 12/19/2022] Open
Abstract
Acidic pH shift occurs in many physiological neuronal activities such as synaptic transmission and synaptic plasticity but also represents a characteristic feature of many pathological conditions including inflammation and ischemia. Neuroinflammation is a complex process that occurs in various neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, and Huntington’s disease. Acid-sensing ion channels (ASICs) represent a widely expressed pH sensor in the brain that play a key role in neuroinflammation. On this basis, acid-sensing ion channel blockers are able to exert neuroprotective effects in different neurodegenerative diseases. In this review, we discuss the multifaceted roles of ASICs in brain physiology and pathology and highlight ASIC1a as a potential pharmacological target in neurodegenerative diseases.
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Affiliation(s)
- Dalila Mango
- Laboratory of Pharmacology of Synaptic Plasticity, European Brain Research Institute, Rome, Italy.,School of Pharmacy, University of Rome "Tor Vergata", Rome, Italy
| | - Robert Nisticò
- Laboratory of Pharmacology of Synaptic Plasticity, European Brain Research Institute, Rome, Italy.,School of Pharmacy, University of Rome "Tor Vergata", Rome, Italy
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9
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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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10
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Liu X, Liu C, Ye J, Zhang S, Wang K, Su R. Distribution of Acid Sensing Ion Channels in Axonal Growth Cones and Presynaptic Membrane of Cultured Hippocampal Neurons. Front Cell Neurosci 2020; 14:205. [PMID: 32733209 PMCID: PMC7358772 DOI: 10.3389/fncel.2020.00205] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 06/10/2020] [Indexed: 12/24/2022] Open
Abstract
Although acid-sensing ion channels (ASICs) are widely expressed in the central nervous system, their distribution and roles in axonal growth cones remain unclear. In this study, we examined ASIC localization and function in the axonal growth cones of cultured immature hippocampal neurons. Our immunocytochemical data showed that native and overexpressed ASIC1a and ASIC2a are both localized in growth cones of cultured young hippocampal neurons. Calcium imaging and electrophysiological assay results were utilized to validate their function. The calcium imaging test results indicated that the ASICs (primarily ASIC1a) present in growth cones mediate calcium influx despite the addition of voltage-gated Ca2+ channels antagonists and the depletion of intracellular calcium stores. The electrophysiological tests results suggested that a rapid decrease in extracellular pH at the growth cones of voltage-clamped neurons elicits inward currents that were blocked by bath application of the ASIC antagonist amiloride, showing that the ASICs expressed at growth cones are functional. The subsequent immuno-colocalization test results demonstrated that ASIC1a and ASIC2a are both colocalized with Neurofilament-H and Bassoon in mature hippocampal neurons. This finding demonstrated that after reaching maturity, ASIC1a and ASIC2a are both distributed in axons and the presynaptic membrane. Our data reveal the distribution of functional ASICs in growth cones of immature hippocampal neurons and the presence of ASICs in the axons and presynaptic membrane of mature hippocampal neurons, indicating a possible role for ASICs in axonal guidance, synapse formation and neurotransmitter release.
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Affiliation(s)
- Xiaoyan Liu
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Can Liu
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Jiamin Ye
- School of Pharmacy, North China University of Science and Technology, Tangshan, China
| | - Shuzhuo Zhang
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Kai Wang
- State Key Laboratory of Proteomics, National Center of Biomedical Analysis, Beijing, China
| | - Ruibin Su
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Beijing Institute of Pharmacology and Toxicology, Beijing, China
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11
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Mango D, Nisticò R. Role of ASIC1a in Normal and Pathological Synaptic Plasticity. Rev Physiol Biochem Pharmacol 2020; 177:83-100. [PMID: 32789788 DOI: 10.1007/112_2020_45] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Acid-sensing ion channels (ASICs), members of the degenerin/epithelial Na+ channel superfamily, are broadly distributed in the mammalian nervous system where they play important roles in a variety of physiological processes, including neurotransmission and memory-related behaviors. In the last few years, we and others have investigated the role of ASIC1a in different forms of synaptic plasticity especially in the CA1 area of the hippocampus. This review summarizes the latest research linking ASIC1a to synaptic function either in physiological or pathological conditions. A better understanding of how these channels are regulated in brain circuitries relevant to synaptic plasticity and memory may offer novel targets for pharmacological intervention in neuropsychiatric and neurological disorders.
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Affiliation(s)
- Dalila Mango
- Laboratory of Pharmacology of Synaptic Plasticity, EBRI Rita Levi-Montalcini Foundation, Rome, Italy.
| | - Robert Nisticò
- Laboratory of Pharmacology of Synaptic Plasticity, EBRI Rita Levi-Montalcini Foundation, Rome, Italy
- School of Pharmacy, University of Rome Tor Vergata, Rome, Italy
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12
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Zhang RJ, Yin YF, Xie XJ, Gu HF. Acid-sensing ion channels: Linking extracellular acidification with atherosclerosis. Clin Chim Acta 2019; 502:183-190. [PMID: 31901478 DOI: 10.1016/j.cca.2019.12.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 12/30/2019] [Accepted: 12/30/2019] [Indexed: 01/02/2023]
Abstract
Extracellular acidification in atherosclerosis-prone regions of arterial walls is considered pro-atherosclerotic by exerting detrimental effect on macrophages, endothelial cells (ECs) and vascular smooth muscle cells (VSMCs). Acid-sensing ion channels (ASICs), a family of extracellular H+ (proton)-gated cation channels, are present extensively in the nervous system and other tissues, implying physiologic as well as pathophysiologic importance. Aberrant activation of ASICs is thought to be associated in EC dysfunction, macrophage phenotypic switch, and VSMC migration and proliferation. Although in vitro evidence acknowledges the contribution of ASIC activation in atherosclerosis, no direct evidence confirms their pro-atherosclerotic roles in vivo. In this review, the effect of extracellular acidity on three major contributors, ECs, macrophages, and VSMCs, is discussed focusing on the potential roles of ASICs in atherosclerotic development and underlying pathology. A more comprehensive understanding of ASICs in these processes may provide promising new therapeutic targets for treatment and prevention of atherosclerotic diseases.
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Affiliation(s)
- Rong-Jie Zhang
- Department of Physiology & Institute of Neuroscience, University of South China, Hengyang, People's Republic of China
| | - Yu-Fang Yin
- Department of Neuroscience and Pharmacology, School of Medicine, Southern Illinois University Springfield, Illinois, United States
| | - Xue-Jiao Xie
- Department of Zhongjing' Theory, College of Chinese Medicine, Hunan University of Chinese Medicine, Changsha, People's Republic of China.
| | - Hong-Feng Gu
- Department of Physiology & Institute of Neuroscience, University of South China, Hengyang, People's Republic of China.
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13
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Kasimova MA, Lynagh T, Sheikh ZP, Granata D, Borg CB, Carnevale V, Pless SA. Evolutionarily Conserved Interactions within the Pore Domain of Acid-Sensing Ion Channels. Biophys J 2019; 118:861-872. [PMID: 31630811 DOI: 10.1016/j.bpj.2019.09.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 08/25/2019] [Accepted: 09/03/2019] [Indexed: 12/14/2022] Open
Abstract
Despite the sequence homology between acid-sensing ion channels (ASICs) and epithelial sodium channel (ENaCs), these channel families display very different functional characteristics. Whereas ASICs are gated by protons and show a relatively low degree of selectivity for sodium over potassium, ENaCs are constitutively active and display a remarkably high degree of sodium selectivity. To decipher if some of the functional diversity originates from differences within the transmembrane helices (M1 and M2) of both channel families, we turned to a combination of computational and functional interrogations, using statistical coupling analysis and mutational studies on mouse ASIC1a. The coupling analysis suggests that the relative position of M1 and M2 in the upper part of the pore domain is likely to remain constant during the ASIC gating cycle, whereas they may undergo relative movements in the lower part. Interestingly, our data suggest that to account for coupled residue pairs being in close structural proximity, both domain-swapped and nondomain-swapped ASIC M2 conformations need to be considered. Such conformational flexibility is consistent with structural work, which suggested that the lower part of M2 can adopt both domain-swapped and nondomain-swapped conformations. Overall, mutations to residues in the middle and lower pore were more likely to affect gating and/or ion selectivity than those in the upper pore. Indeed, disrupting the putative interaction between a highly conserved Trp/Glu residue pair in the lower pore is detrimental to gating and selectivity, although this interaction might occur in both domain-swapped and nonswapped conformations. Finally, our results suggest that the greater number of larger, aromatic side chains in the ENaC M2 helix may contribute to the constitutive activity of these channels at a resting pH. Together, the data highlight differences in the transmembrane domains of these closely related ion channels that may help explain some of their distinct functional properties.
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Affiliation(s)
- Marina A Kasimova
- Department of Applied Physics, KTH Royal Institute of Technology, Stockholm, Sweden
| | | | | | - Daniele Granata
- Institute for Computational Molecular Science, Temple University, Philadelphia, Pennsylvania
| | | | - Vincenzo Carnevale
- Institute for Computational Molecular Science, Temple University, Philadelphia, Pennsylvania.
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