1
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Ji R, Chang L, An C, Zhang J. Proton-sensing ion channels, GPCRs and calcium signaling regulated by them: implications for cancer. Front Cell Dev Biol 2024; 12:1326231. [PMID: 38505262 PMCID: PMC10949864 DOI: 10.3389/fcell.2024.1326231] [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: 10/25/2023] [Accepted: 02/14/2024] [Indexed: 03/21/2024] Open
Abstract
Extracellular acidification of tumors is common. Through proton-sensing ion channels or proton-sensing G protein-coupled receptors (GPCRs), tumor cells sense extracellular acidification to stimulate a variety of intracellular signaling pathways including the calcium signaling, which consequently exerts global impacts on tumor cells. Proton-sensing ion channels, and proton-sensing GPCRs have natural advantages as drug targets of anticancer therapy. However, they and the calcium signaling regulated by them attracted limited attention as potential targets of anticancer drugs. In the present review, we discuss the progress in studies on proton-sensing ion channels, and proton-sensing GPCRs, especially emphasizing the effects of calcium signaling activated by them on the characteristics of tumors, including proliferation, migration, invasion, metastasis, drug resistance, angiogenesis. In addition, we review the drugs targeting proton-sensing channels or GPCRs that are currently in clinical trials, as well as the relevant potential drugs for cancer treatments, and discuss their future prospects. The present review aims to elucidate the important role of proton-sensing ion channels, GPCRs and calcium signaling regulated by them in cancer initiation and development. This review will promote the development of drugs targeting proton-sensing channels or GPCRs for cancer treatments, effectively taking their unique advantage as anti-cancer drug targets.
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Affiliation(s)
- Renhui Ji
- Foundational and Translational Medical Research Center, Department of Allergy and General Surgery, Hohhot First Hospital, Hohhot, China
- Department of Pathophysiology, Basic Medicine College of Inner Mongolia Medical University, Hohhot, China
| | - Li Chang
- Foundational and Translational Medical Research Center, Department of Allergy and General Surgery, Hohhot First Hospital, Hohhot, China
- Department of Pathophysiology, Basic Medicine College of Inner Mongolia Medical University, Hohhot, China
| | - Caiyan An
- Foundational and Translational Medical Research Center, Department of Allergy and General Surgery, Hohhot First Hospital, Hohhot, China
| | - Junjing Zhang
- Foundational and Translational Medical Research Center, Department of Allergy and General Surgery, Hohhot First Hospital, Hohhot, China
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2
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Hawashin A, Brakmann IC, Tian Y, Gründer S, Ortega-Ramírez AM. Modulation of Acid-Sensing Ion Channels by Tannic Acid and Green Tea via a Membrane-Mediated Mechanism. ACS Chem Neurosci 2023. [PMID: 37379568 DOI: 10.1021/acschemneuro.3c00032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/30/2023] Open
Abstract
Acid-sensing ion channels (ASICs) are proton-gated ion channels that contribute to pain perception and neurotransmission. Being involved in sensing inflammation and ischemia, ASIC1a and ASIC3 are promising drug targets. Polyphenol tannic acid (TA) as well as green tea can interact with a variety of ion channels, but their effect on ASICs remains unknown. In addition, it is unknown whether they interact with ion channels via a common mechanism. Here, we show that TA is a potent modulator of ASICs. TA inhibited the transient current of rat ASIC3 expressed in HEK cells with an apparent IC50 of 2.2 ± 0.6 μM; it potentiated the sustained current and induced a slowly declining decay current. In addition, it produced an acidic shift of the pH-dependent activation of ASIC3 and inhibited the window current at pH 7.0. Moreover, TA inhibited the transient current of ASIC1a, ASIC1b, and ASIC2a. Pentagalloylglucose that is chemically identical to the central part of TA and a green tea extract both had effects on ASIC3 comparable to TA. TA and green tea inhibited inward currents generated by gramicidin channels, indicating interaction with the membrane. These results show that TA, pentagalloylglucose, and green tea modulate ASICs and identify alteration of the membrane as the potential common mechanism of this modulation. These properties will limit clinical application of these molecules.
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Affiliation(s)
- Ammar Hawashin
- Institute of Physiology, RWTH Aachen University, Pauwelsstraße 30, Aachen D-52074, Germany
| | - Ilka C Brakmann
- Institute of Physiology, RWTH Aachen University, Pauwelsstraße 30, Aachen D-52074, Germany
| | - Yuemin Tian
- Institute of Physiology, RWTH Aachen University, Pauwelsstraße 30, Aachen D-52074, Germany
| | - Stefan Gründer
- Institute of Physiology, RWTH Aachen University, Pauwelsstraße 30, Aachen D-52074, Germany
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3
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Garcia SM, Naik JS, Resta TC, Jernigan NL. Acid-sensing ion channel 1a activates IKCa/SKCa channels and contributes to endothelium-dependent dilation. J Gen Physiol 2023; 155:e202213173. [PMID: 36484717 PMCID: PMC9984545 DOI: 10.1085/jgp.202213173] [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: 04/12/2022] [Revised: 10/21/2022] [Accepted: 11/17/2022] [Indexed: 12/13/2022] Open
Abstract
Acid-sensing ion channel 1a (ASIC1a) belongs to a novel family of proton-gated cation channels that are permeable to both Na+ and Ca2+. ASIC1a is expressed in vascular smooth muscle and endothelial cells in a variety of vascular beds, yet little is known regarding the potential impact of ASIC1a to regulate local vascular reactivity. Our previous studies in rat mesenteric arteries suggest ASIC1a does not contribute to agonist-induced vasoconstriction but may mediate a vasodilatory response. The objective of the current study is to determine the role of ASIC1a in systemic vasodilatory responses by testing the hypothesis that the activation of endothelial ASIC1a mediates vasodilation of mesenteric resistance arteries through an endothelium-dependent hyperpolarization (EDH)-related pathway. The selective ASIC1a antagonist psalmotoxin 1 (PcTX1) largely attenuated the sustained vasodilatory response to acetylcholine (ACh) in isolated, pressurized mesenteric resistance arteries and ACh-mediated Ca2+ influx in freshly isolated mesenteric endothelial tubes. Similarly, basal tone was enhanced and ACh-induced vasodilation blunted in mesenteric arteries from Asic1a knockout mice. ASIC1a colocalizes with intermediate- and small-conductance Ca2+-activated K+ channels (IKCa and SKCa, respectively), and the IKCa/SKCa-sensitive component of the ACh-mediated vasodilation was blocked by ASIC1a inhibition. To determine the role of ASIC1a to activate IKCa/SKCa channels, we measured whole-cell K+ currents using the perforated-patch clamp technique in freshly isolated mesenteric endothelial cells. Inhibition of ASIC1a prevented ACh-induced activation of IKCa/SKCa channels. The ASIC1 agonist, α/β-MitTx, activated IKCa/SKCa channels and induced an IKCa/SKCa-dependent vasodilation. Together, the present study demonstrates that ASIC1a couples to IKCa/SKCa channels in mesenteric resistance arteries to mediate endothelium-dependent vasodilation.
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Affiliation(s)
- Selina M. Garcia
- Department of Cell Biology and Physiology University of New Mexico School of Medicine, Albuquerque, NM
| | - Jay S. Naik
- Department of Cell Biology and Physiology University of New Mexico School of Medicine, Albuquerque, NM
| | - Thomas C. Resta
- Department of Cell Biology and Physiology University of New Mexico School of Medicine, Albuquerque, NM
| | - Nikki L. Jernigan
- Department of Cell Biology and Physiology University of New Mexico School of Medicine, Albuquerque, NM
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4
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Klipp RC, Bankston JR. A loosely coordinated interaction site for arachidonic acid on ASICs. J Gen Physiol 2023; 155:213849. [PMID: 36723670 PMCID: PMC9929933 DOI: 10.1085/jgp.202213307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Molecular dynamics simulations reveal a putative interaction surface for PUFAs on TM1 of ASICs that is not tightly conserved between isoforms.
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Affiliation(s)
- 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,Correspondence to John R. Bankston:
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5
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Ananchenko A, Musgaard M. Multiscale molecular dynamics simulations predict arachidonic acid binding sites in human ASIC1a and ASIC3 transmembrane domains. J Gen Physiol 2023; 155:213797. [PMID: 36625864 PMCID: PMC9836442 DOI: 10.1085/jgp.202213259] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/20/2022] [Accepted: 12/21/2022] [Indexed: 01/11/2023] Open
Abstract
Acid-sensing ion channels (ASICs) play important roles in inflammatory pathways by conducting ions across the neuronal membrane in response to proton binding under acidic conditions. Recent studies have shown that ASICs can be modulated by arachidonic acid (AA), and, in the case of the ASIC3 subtype, even activated by AA at physiological pH. However, the mechanism by which these fatty acids act on the channel is still unknown. Here, we have used multiscale molecular dynamics simulations to predict a putative, general binding region of AA to models of the human ASIC protein. We have identified, in agreement with recent studies, residues in the outer leaflet transmembrane region which interact with AA. In addition, despite their similar modulation, we observe subtle differences in the AA interaction pattern between human ASIC1a and human ASIC3, which can be reversed by mutating three key residues at the outer leaflet portion of TM1. We further probed interactions with these residues in hASIC3 using atomistic simulations and identified possible AA coordinating interactions; salt bridge interactions of AA with R65hASIC3 and R68hASIC3 and AA tail interactions with the Y58hASIC3 aromatic ring. We have shown that longer fatty acid tails with more double bonds have increased relative occupancy in this region of the channel, a finding supported by recent functional studies. We further proposed that the modulatory effect of AA on ASIC does not result from changes in local membrane curvature. Rather, we speculate that it may occur through structural changes to the ion channel upon AA binding.
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Affiliation(s)
- Anna Ananchenko
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Canada,Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Maria Musgaard
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Canada
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6
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Zhou RP, Liang HY, Hu WR, Ding J, Li SF, Chen Y, Zhao YJ, Lu C, Chen FH, Hu W. Modulators of ASIC1a and its potential as a therapeutic target for age-related diseases. Ageing Res Rev 2023; 83:101785. [PMID: 36371015 DOI: 10.1016/j.arr.2022.101785] [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: 06/24/2022] [Revised: 10/30/2022] [Accepted: 11/07/2022] [Indexed: 11/10/2022]
Abstract
Age-related diseases have become more common with the advancing age of the worldwide population. Such diseases involve multiple organs, with tissue degeneration and cellular apoptosis. To date, there is a general lack of effective drugs for treatment of most age-related diseases and there is therefore an urgent need to identify novel drug targets for improved treatment. Acid-sensing ion channel 1a (ASIC1a) is a degenerin/epithelial sodium channel family member, which is activated in an acidic environment to regulate pathophysiological processes such as acidosis, inflammation, hypoxia, and ischemia. A large body of evidence suggests that ASIC1a plays an important role in the development of age-related diseases (e.g., stroke, rheumatoid arthritis, Huntington's disease, and Parkinson's disease.). Herein we present: 1) a review of ASIC1a channel properties, distribution, and physiological function; 2) a summary of the pharmacological properties of ASIC1a; 3) and a consideration of ASIC1a as a potential therapeutic target for treatment of age-related disease.
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Affiliation(s)
- Ren-Peng Zhou
- Department of Clinical Pharmacology, The Second Hospital of Anhui Medical University, Hefei 230601, China; The Key Laboratory of Anti-inflammatory and Immune Medicine, Anhui Medical University, Ministry of Education, Hefei 230032, China
| | - Hong-Yu Liang
- The Second School of Clinical Medicine, Anhui Medical University, Hefei 230032, China
| | - Wei-Rong Hu
- School of Pharmacy, Anhui Medical University, Hefei 230032, China
| | - Jie Ding
- Department of Clinical Pharmacology, The Second Hospital of Anhui Medical University, Hefei 230601, China
| | - Shu-Fang Li
- Department of Clinical Pharmacology, The Second Hospital of Anhui Medical University, Hefei 230601, China
| | - Yong Chen
- Department of Clinical Pharmacology, The Second Hospital of Anhui Medical University, Hefei 230601, China
| | - Ying-Jie Zhao
- Department of Clinical Pharmacology, The Second Hospital of Anhui Medical University, Hefei 230601, China; The Key Laboratory of Anti-inflammatory and Immune Medicine, Anhui Medical University, Ministry of Education, Hefei 230032, China
| | - Chao Lu
- First Affiliated Hospital, Anhui University of Science & Technology, Huainan 232001, China
| | - Fei-Hu Chen
- School of Pharmacy, Anhui Medical University, Hefei 230032, China
| | - Wei Hu
- Department of Clinical Pharmacology, The Second Hospital of Anhui Medical University, Hefei 230601, China; The Key Laboratory of Anti-inflammatory and Immune Medicine, Anhui Medical University, Ministry of Education, Hefei 230032, China.
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7
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Booth LN, Shi C, Tantilert C, Yeo RW, Miklas JW, Hebestreit K, Hollenhorst CN, Maures TJ, Buckley MT, Murphy CT, Brunet A. Males induce premature demise of the opposite sex by multifaceted strategies. NATURE AGING 2022; 2:809-823. [PMID: 37118502 PMCID: PMC10154206 DOI: 10.1038/s43587-022-00276-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Accepted: 08/03/2022] [Indexed: 04/30/2023]
Abstract
Interactions between the sexes negatively impact health in many species. In Caenorhabditis, males shorten the lifespan of the opposite sex-hermaphrodites or females. Here we use transcriptomic profiling and targeted screens to systematically uncover conserved genes involved in male-induced demise in C. elegans. Some genes (for example, delm-2, acbp-3), when knocked down, are specifically protective against male-induced demise. Others (for example, sri-40), when knocked down, extend lifespan with and without males, suggesting general mechanisms of protection. In contrast, many classical long-lived mutants are impacted more negatively than wild type by the presence of males, highlighting the importance of sexual environment for longevity. Interestingly, genes induced by males are triggered by specific male components (seminal fluid, sperm and pheromone), and manipulating these genes in combination in hermaphrodites induces stronger protection. One of these genes, the conserved ion channel delm-2, acts in the nervous system and intestine to regulate lipid metabolism. Our analysis reveals striking differences in longevity in single sex versus mixed sex environments and uncovers elaborate strategies elicited by sexual interactions that could extend to other species.
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Affiliation(s)
- Lauren N Booth
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
- Calico Life Sciences, South San Francisco, CA, USA
| | - Cheng Shi
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
- LSI Genomics, Princeton University, Princeton, NJ, USA
| | - Cindy Tantilert
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Robin W Yeo
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Jason W Miklas
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Katja Hebestreit
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | | | - Travis J Maures
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Matthew T Buckley
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Coleen T Murphy
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA.
- LSI Genomics, Princeton University, Princeton, NJ, USA.
| | - Anne Brunet
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA.
- Glenn Laboratories for the Biology of Aging and Stanford University, Stanford, CA, USA.
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8
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Liin SI. ASIC3, a proton-gated ion channel with preference for polyunsaturated lipids with specific headgroup and tail properties. J Gen Physiol 2022; 154:e202213171. [PMID: 35583814 PMCID: PMC9121178 DOI: 10.1085/jgp.202213171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Commentary highlighting valuable mechanistic insights provided by Klipp and Bankston on ASIC3 regulation by lipids.
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Affiliation(s)
- Sara I. Liin
- Department of Biomedical and Clinical Sciences, Division of Neurobiology, Linköping University, Linköping, Sweden
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9
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Klipp RC, Bankston JR. Structural determinants of acid-sensing ion channel potentiation by single chain lipids. J Gen Physiol 2022; 154:e202213156. [PMID: 35583813 PMCID: PMC9120901 DOI: 10.1085/jgp.202213156] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 05/02/2022] [Indexed: 01/07/2023] Open
Abstract
Acid-sensing ion channels (ASICs) are sensitized to activation by inflammatory mediators such as the polyunsaturated fatty acid (PUFA) arachidonic acid (AA). Previous work has shown that AA can potentiate ASIC currents at subsaturating proton concentrations, but the structural mechanisms of this change in gating are not understood. Here we show that PUFAs cause multiple gating changes in ASIC3, including shifting the pH dependence of activation, slowing the rate of desensitization, and increasing the current even at a saturating pH. The impact on gating depends on the nature of both the head and tail of the lipid, with the head group structure primarily determining the magnitude of the effect on the channel. An N-acyl amino acid (NAAA), arachidonyl glycine (AG), is such a strong regulator that it can act as a ligand at neutral pH. Mutation of an arginine in the outer segment of TM1 (R64) eliminated the effect of docosahexaenoic acid (DHA) even at high concentrations, suggesting a potential interaction site for the lipid on the channel. Our results suggest a model in which PUFAs bind to ASICs via both their tail group and an electrostatic interaction between the negatively charged PUFA head group and the positively charged arginine side chain. These data provide the first look at the structural features of lipids that are important for modulating ASICs and suggest a potential binding site for PUFAs on the channel.
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Affiliation(s)
- Robert C. Klipp
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - John R. Bankston
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO
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10
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Butenas ALE, Rollins KS, Parr SK, Hammond ST, Ade CJ, Hageman KS, Musch TI, Copp SW. Novel mechanosensory role for acid sensing ion channel subtype 1a in evoking the exercise pressor reflex in rats with heart failure. J Physiol 2022; 600:2105-2125. [PMID: 35343594 PMCID: PMC9893514 DOI: 10.1113/jp282923] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 03/18/2022] [Indexed: 02/05/2023] Open
Abstract
Mechanical and metabolic signals associated with skeletal muscle contraction stimulate the sensory endings of thin fibre muscle afferents, which, in turn, generates reflex increases in sympathetic nerve activity (SNA) and blood pressure (the exercise pressor reflex; EPR). EPR activation in patients and animals with heart failure with reduced ejection fraction (HF-rEF) results in exaggerated increases in SNA and promotes exercise intolerance. In the healthy decerebrate rat, a subtype of acid sensing ion channel (ASIC) on the sensory endings of thin fibre muscle afferents, namely ASIC1a, has been shown to contribute to the metabolically sensitive portion of the EPR (i.e. metaboreflex), but not the mechanically sensitive portion of the EPR (i.e. the mechanoreflex). However, the role played by ASIC1a in evoking the EPR in HF-rEF is unknown. We hypothesized that, in decerebrate, unanaesthetized HF-rEF rats, injection of the ASIC1a antagonist psalmotoxin-1 (PcTx-1; 100 ng) into the hindlimb arterial supply would reduce the reflex increase in renal SNA (RSNA) evoked via 30 s of electrically induced static hindlimb muscle contraction, but not static hindlimb muscle stretch (model of mechanoreflex activation isolated from contraction-induced metabolite-production). We found that PcTx-1 reduced the reflex increase in RSNA evoked in response to muscle contraction (n = 8; mean (SD) ∫ΔRSNA pre: 1343 (588) a.u.; post: 816 (573) a.u.; P = 0.026) and muscle stretch (n = 6; ∫ΔRSNA pre: 688 (583) a.u.; post: 304 (370) a.u.; P = 0.025). Our data suggest that, in HF-rEF rats, ASIC1a contributes to activation of the exercise pressor reflex and that contribution includes a novel role for ASIC1a in mechanosensation that is not present in healthy rats. KEY POINTS: Skeletal muscle contraction results in exaggerated reflex increases in sympathetic nerve activity in heart failure patients compared to healthy counterparts, which likely contributes to increased cardiovascular risk and impaired tolerance for even mild exercise (i.e. activities of daily living) for patients suffering with this condition. Activation of acid sensing ion channel subtype 1a (ASIC1a) on the sensory endings of thin fibre muscle afferents during skeletal muscle contraction contributes to reflex increases in sympathetic nerve activity and blood pressure, at least in healthy subjects. In this study, we demonstrate that ASIC1a on the sensory endings of thin fibre muscle afferents plays a role in both the mechanical and metabolic components of the exercise pressor reflex in male rats with heart failure. The present data identify a novel role for ASIC1a in evoking the exercise pressor reflex in heart failure and may have important clinical implications for heart failure patients.
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Affiliation(s)
| | | | - Shannon K. Parr
- Department of Kinesiology, Kansas State University, Manhattan, KS, USA
| | | | - Carl J. Ade
- Department of Kinesiology, Kansas State University, Manhattan, KS, USA
| | - K. Sue Hageman
- Department of Anatomy and Physiology, Kansas State University, Manhattan, KS, USA
| | - Timothy I. Musch
- Department of Kinesiology, Kansas State University, Manhattan, KS, USA,Department of Anatomy and Physiology, Kansas State University, Manhattan, KS, USA
| | - Steven W. Copp
- Department of Kinesiology, Kansas State University, Manhattan, KS, USA
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11
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Dulai JS, Smith ESJ, Rahman T. Acid-sensing ion channel 3: An analgesic target. Channels (Austin) 2021; 15:94-127. [PMID: 33258401 PMCID: PMC7801124 DOI: 10.1080/19336950.2020.1852831] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 11/13/2020] [Indexed: 12/12/2022] Open
Abstract
Acid-sensing ion channel 3 (ASIC3) belongs to the epithelial sodium channel/degenerin (ENaC/DEG) superfamily. There are 7 different ASIC subunits encoded by 5 different genes. Most ASIC subunits form trimeric ion channels that upon activation by extracellular protons mediate a transient inward current inducing cellular excitability. ASIC subunits exhibit differential tissue expression and biophysical properties, and the ability of subunits to form homo- and heteromeric trimers further increases the complexity of currents measured and their pharmacological properties. ASIC3 is of particular interest, not only because it exhibits high expression in sensory neurones, but also because upon activation it does not fully inactivate: a transient current is followed by a sustained current that persists during a period of extracellular acidity, i.e. ASIC3 can encode prolonged acidosis as a nociceptive signal. Furthermore, certain mediators sensitize ASIC3 enabling smaller proton concentrations to activate it and other mediators can directly activate the channel at neutral pH. Moreover, there is a plethora of evidence using transgenic mouse models and pharmacology, which supports ASIC3 as being a potential target for development of analgesics. This review will focus on current understanding of ASIC3 function to provide an overview of how ASIC3 contributes to physiology and pathophysiology, examining the mechanisms by which it can be modulated, and highlighting gaps in current understanding and future research directions.
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Affiliation(s)
| | | | - Taufiq Rahman
- Department of Pharmacology, University of Cambridge, Cambridge, UK
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12
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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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13
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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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14
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Mukhopadhyay M, Bera AK. Modulation of acid-sensing ion channels by hydrogen sulfide. Biochem Biophys Res Commun 2020; 527:71-75. [PMID: 32446393 DOI: 10.1016/j.bbrc.2020.04.092] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Accepted: 04/17/2020] [Indexed: 01/30/2023]
Abstract
Acid-sensing ion channels (ASICs) have been implicated in many physiological and patho-physiological processes like synaptic plasticity, inflammation, pain perception, stroke-induced brain damage and, drug-seeking behaviour. Although ASICs have been shown to be modulated by gasotransmitters like nitric oxide (NO), their regulation by hydrogen sulfide (H2S) is not known. Here, we present strong evidence that H2S potentiates ASICs-mediated currents. Low pH-induced current in Chinese hamster ovary (CHO) cells, expressing homomeric either ASIC1a, ASIC2a or ASIC3, increased significantly by an H2S donor NaHS. The effect was reversed by washing the cells with NaHS-free external solution of pH 7.4. MTSES, a membrane impermeable cysteine thiol-modifier failed to abrogate the effect of NaHS on ASIC1a, suggesting that the target cysteine residues are not in the extracellular region of the channel. The effect of NaHS is not mediated through NO, as the basal NO level in cells did not change following NaHS application. This previously unknown mechanism of ASICs-modulation by H2S adds a new dimension to the ASICs in health and disease.
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Affiliation(s)
- Mohona Mukhopadhyay
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, 600036, Tamil Nadu, India
| | - Amal Kanti Bera
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, 600036, Tamil Nadu, India.
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15
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Fontaine D, Figiel S, Félix R, Kouba S, Fromont G, Mahéo K, Potier-Cartereau M, Chantôme A, Vandier C. Roles of endogenous ether lipids and associated PUFAs in the regulation of ion channels and their relevance for disease. J Lipid Res 2020; 61:840-858. [PMID: 32265321 PMCID: PMC7269763 DOI: 10.1194/jlr.ra120000634] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 03/29/2020] [Indexed: 12/16/2022] Open
Abstract
Ether lipids (ELs) are lipids characterized by the presence of either an ether linkage (alkyl lipids) or a vinyl ether linkage [i.e., plasmalogens (Pls)] at the sn1 position of the glycerol backbone, and they are enriched in PUFAs at the sn2 position. In this review, we highlight that ELs have various biological functions, act as a reservoir for second messengers (such as PUFAs) and have roles in many diseases. Some of the biological effects of ELs may be associated with their ability to regulate ion channels that control excitation-contraction/secretion/mobility coupling and therefore cell physiology. These channels are embedded in lipid membranes, and lipids can regulate their activities directly or indirectly as second messengers or by incorporating into membranes. Interestingly, ELs and EL-derived PUFAs have been reported to play a key role in several pathologies, including neurological disorders, cardiovascular diseases, and cancers. Investigations leading to a better understanding of their mechanisms of action in pathologies have opened a new field in cancer research. In summary, newly identified lipid regulators of ion channels, such as ELs and PUFAs, may represent valuable targets to improve disease diagnosis and advance the development of new therapeutic strategies for managing a range of diseases and conditions.
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Affiliation(s)
- Delphine Fontaine
- Inserm N2C UMR1069, Université de Tours, F-37032 Tours CEDEX 1, France
| | - Sandy Figiel
- Inserm N2C UMR1069, Université de Tours, F-37032 Tours CEDEX 1, France
| | - Romain Félix
- Inserm N2C UMR1069, Université de Tours, F-37032 Tours CEDEX 1, France
| | - Sana Kouba
- Inserm N2C UMR1069, Université de Tours, F-37032 Tours CEDEX 1, France
| | - Gaëlle Fromont
- Inserm N2C UMR1069, Université de Tours, F-37032 Tours CEDEX 1, France; Department of Pathology, CHRU Bretonneau, F-37044 Tours CEDEX 9, France
| | - Karine Mahéo
- Inserm N2C UMR1069, Université de Tours, F-37032 Tours CEDEX 1, France; Faculté de Pharmacie, Université de Tours, F-37200 Tours, France
| | | | - Aurélie Chantôme
- Inserm N2C UMR1069, Université de Tours, F-37032 Tours CEDEX 1, France; Faculté de Pharmacie, Université de Tours, F-37200 Tours, France
| | - Christophe Vandier
- Inserm N2C UMR1069, Université de Tours, F-37032 Tours CEDEX 1, France. mailto:
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16
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A molecular view of the function and pharmacology of acid-sensing ion channels. Pharmacol Res 2020; 154:104166. [DOI: 10.1016/j.phrs.2019.02.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 02/01/2019] [Accepted: 02/02/2019] [Indexed: 02/06/2023]
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17
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Alijevic O, Bignucolo O, Hichri E, Peng Z, Kucera JP, Kellenberger S. Slowing of the Time Course of Acidification Decreases the Acid-Sensing Ion Channel 1a Current Amplitude and Modulates Action Potential Firing in Neurons. Front Cell Neurosci 2020; 14:41. [PMID: 32180707 PMCID: PMC7059123 DOI: 10.3389/fncel.2020.00041] [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: 11/05/2019] [Accepted: 02/12/2020] [Indexed: 12/14/2022] Open
Abstract
Acid-sensing ion channels (ASICs) are H+-activated neuronal Na+ channels. They are involved in fear behavior, learning, neurodegeneration after ischemic stroke and in pain sensation. ASIC activation has so far been studied only with fast pH changes, although the pH changes associated with many roles of ASICs are slow. It is currently not known whether slow pH changes can open ASICs at all. Here, we investigated to which extent slow pH changes can activate ASIC1a channels and induce action potential signaling. To this end, ASIC1a current amplitudes and charge transport in transfected Chinese hamster ovary cells, and ASIC-mediated action potential signaling in cultured cortical neurons were measured in response to defined pH ramps of 1-40 s duration from pH 7.4 to pH 6.6 or 6.0. A kinetic model of the ASIC1a current was developed and integrated into the Hodgkin-Huxley action potential model. Interestingly, whereas the ASIC1a current amplitude decreased with slower pH ramps, action potential firing was higher upon intermediate than fast acidification in cortical neurons. Indeed, fast pH changes (<4 s) induced short action potential bursts, while pH changes of intermediate speed (4-10 s) induced longer bursts. Slower pH changes (>10 s) did in many experiments not generate action potentials. Computer simulations corroborated these observations. We provide here the first description of ASIC function in response to defined slow pH changes. Our study shows that ASIC1a currents, and neuronal activity induced by ASIC1a currents, strongly depend on the speed of pH changes. Importantly, with pH changes that take >10 s to complete, ASIC1a activation is inefficient. Therefore, it is likely that currently unknown modulatory mechanisms allow ASIC activity in situations such as ischemia and inflammation.
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Affiliation(s)
- Omar Alijevic
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Olivier Bignucolo
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland.,SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Echrak Hichri
- Department of Physiology, University of Bern, Bern, Switzerland
| | - Zhong Peng
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Jan P Kucera
- Department of Physiology, University of Bern, Bern, Switzerland
| | - Stephan Kellenberger
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
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18
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Callejo G, Pattison LA, Greenhalgh JC, Chakrabarti S, Andreopoulou E, Hockley JRF, Smith ESJ, Rahman T. In silico screening of GMQ-like compounds reveals guanabenz and sephin1 as new allosteric modulators of acid-sensing ion channel 3. Biochem Pharmacol 2020; 174:113834. [PMID: 32027884 PMCID: PMC7068650 DOI: 10.1016/j.bcp.2020.113834] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 01/31/2020] [Indexed: 11/25/2022]
Abstract
Acid-sensing ion channels (ASICs) are voltage-independent cation channels that detect decreases in extracellular pH. Dysregulation of ASICs underpins a number of pathologies. Of particular interest is ASIC3, which is recognised as a key sensor of acid-induced pain and is important in the establishment of pain arising from inflammatory conditions, such as rheumatoid arthritis. Thus, the identification of new ASIC3 modulators and the mechanistic understanding of how these compounds modulate ASIC3 could be important for the development of new strategies to counteract the detrimental effects of dysregulated ASIC3 activity in inflammation. Here, we report the identification of novel ASIC3 modulators based on the ASIC3 agonist, 2-guanidine-4-methylquinazoline (GMQ). Through a GMQ-guided in silico screening of Food and Drug administration (FDA)-approved drugs, 5 compounds were selected and tested for their modulation of rat ASIC3 (rASIC3) using whole-cell patch-clamp electrophysiology. Of the chosen drugs, guanabenz (GBZ), an α2-adrenoceptor agonist, produced similar effects to GMQ on rASIC3, activating the channel at physiological pH (pH 7.4) and potentiating its response to mild acidic (pH 7) stimuli. Sephin1, a GBZ derivative that lacks α2-adrenoceptor activity, has been proposed to act as a selective inhibitor of a regulatory subunit of the stress-induced protein phosphatase 1 (PPP1R15A) with promising therapeutic potential for the treatment of multiple sclerosis. However, we found that like GBZ, sephin1 activates rASIC3 at pH 7.4 and potentiates its response to acidic stimulation (pH 7), i.e. sephin1 is a novel modulator of rASIC3. Furthermore, docking experiments showed that, like GMQ, GBZ and sephin1 likely interact with the nonproton ligand sensor domain of rASIC3. Overall, these data demonstrate the utility of computational analysis for identifying novel ASIC3 modulators, which can be validated with electrophysiological analysis and may lead to the development of better compounds for targeting ASIC3 in the treatment of inflammatory conditions.
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Affiliation(s)
- Gerard Callejo
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Luke A Pattison
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Jack C Greenhalgh
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Sampurna Chakrabarti
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Evangelia Andreopoulou
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - James R F Hockley
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Ewan St John Smith
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom.
| | - Taufiq Rahman
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom.
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19
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Pattison LA, Callejo G, St John Smith E. Evolution of acid nociception: ion channels and receptors for detecting acid. Philos Trans R Soc Lond B Biol Sci 2019; 374:20190291. [PMID: 31544616 PMCID: PMC6790391 DOI: 10.1098/rstb.2019.0291] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/27/2019] [Indexed: 12/13/2022] Open
Abstract
Nociceptors, i.e. sensory neurons tuned to detect noxious stimuli, are found in numerous phyla of the Animalia kingdom and are often polymodal, responding to a variety of stimuli, e.g. heat, cold, pressure and chemicals, such as acid. Owing to the ability of protons to have a profound effect on ionic homeostasis and damage macromolecular structures, it is no wonder that the ability to detect acid is conserved across many species. To detect changes in pH, nociceptors are equipped with an assortment of different acid sensors, some of which can detect mild changes in pH, such as the acid-sensing ion channels, proton-sensing G protein-coupled receptors and several two-pore potassium channels, whereas others, such as the transient receptor potential vanilloid 1 ion channel, require larger shifts in pH. This review will discuss the evolution of acid sensation and the different mechanisms by which nociceptors can detect acid. This article is part of the Theo Murphy meeting issue 'Evolution of mechanisms and behaviour important for pain'.
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Affiliation(s)
| | | | - Ewan St John Smith
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, UK
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20
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Hsu WH, Lee CH, Chao YM, Kuo CH, Ku WC, Chen CC, Lin YL. ASIC3-dependent metabolomics profiling of serum and urine in a mouse model of fibromyalgia. Sci Rep 2019; 9:12123. [PMID: 31431652 PMCID: PMC6702159 DOI: 10.1038/s41598-019-48315-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 07/30/2019] [Indexed: 12/27/2022] Open
Abstract
Fibromyalgia (FM) is characterized by chronic widespread pain. The pathogenesis of FM remains unclear. No specific biomarkers are available. Animal models of FM may provide an opportunity to explore potential biomarkers in a relative homogenous disease condition. Here, we probed the metabolomics profiles of serum and urine in a mouse model of FM induced by intermittent cold stress (ICS). We focused on the role of acid-sensing ion channel 3 (ASIC3) in the metabolomics profiling because ICS treatment induced chronic widespread muscle pain lasting for 1 month in wild-type (Asic3+/+) but not Asic3-knockout (Asic3−/−) mice. Serum and urine samples were collected from both genotypes at different ICS stages, including before ICS (basal level) and post-ICS at days 10 (middle phase, P10) and 40 (recovery phase, P40). Control naïve mice and ICS-induced FM mice differed in 1H-NMR- and LC-MS-based metabolomics profiling. On pathway analysis, the leading regulated pathways in Asic3+/+ mice were taurine and hypotaurine, cysteine and methionine, glycerophospholipid, and ascorbate and aldarate metabolisms, and the major pathways in Asic3−/− mice involved amino acid-related metabolism. Finally, we developed an algorithm for the impactful metabolites in the FM model including cis-aconitate, kynurenate, taurine, pyroglutamic acid, pyrrolidonecarboxylic acid, and 4-methoxyphenylacetic acid in urine as well as carnitine, deoxycholic acid, lysoPC(16:0), lysoPC(20:3), oleoyl-L-carnitine, and trimethylamine N-oxide in serum. Asic3−/− mice were impaired in only muscle allodynia development but not other pain symptoms in the ICS model, so the ASIC3-dependent metabolomics changes could be useful for developing diagnostic biomarkers specific to chronic widespread muscle pain, the core symptom of FM. Further pharmacological validations are needed to validate these metabolomics changes as potential biomarkers for FM diagnosis and/or treatment responses.
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Affiliation(s)
- Wei-Hsiang Hsu
- Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, China Medical University, Taichung, 40402, Taiwan
| | - Cheng-Han Lee
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan
| | - Yen-Ming Chao
- Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, China Medical University, Taichung, 40402, Taiwan
| | - Ching-Hua Kuo
- Department of Pharmacy, National Taiwan University, Taipei, 100, Taiwan
| | - Wei-Chi Ku
- School of Medicine, College of Medicine, Fu Jen Catholic University, New Taipei, 24205, Taiwan
| | - Chih-Cheng Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan. .,Taiwan Mouse Clinic - National Comprehensive Mouse Phenotyping and Drug Testing Center, Academia Sinica, Taipei, 115, Taiwan.
| | - Yun-Lian Lin
- Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, China Medical University, Taichung, 40402, Taiwan.
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21
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Uchitel OD, González Inchauspe C, Weissmann C. Synaptic signals mediated by protons and acid-sensing ion channels. Synapse 2019; 73:e22120. [PMID: 31180161 DOI: 10.1002/syn.22120] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 06/05/2019] [Accepted: 06/05/2019] [Indexed: 01/04/2023]
Abstract
Extracellular pH changes may constitute significant signals for neuronal communication. During synaptic transmission, changes in pH in the synaptic cleft take place. Its role in the regulation of presynaptic Ca2+ currents through multivesicular release in ribbon-type synapses is a proven phenomenon. In recent years, protons have been recognized as neurotransmitters that participate in neuronal communication in synapses of several regions of the CNS such as amygdala, nucleus accumbens, and brainstem. Protons are released by nerve stimulation and activate postsynaptic acid-sensing ion channels (ASICs). Several types of ASIC channels are expressed in the peripheral and central nervous system. The influx of Ca2+ through some subtypes of ASICs, as a result of synaptic transmission, agrees with the participation of ASICs in synaptic plasticity. Pharmacological and genetical inhibition of ASIC1a results in alterations in learning, memory, and phenomena like fear and cocaine-seeking behavior. The recognition of endogenous molecules, such as arachidonic acid, cytokines, histamine, spermine, lactate, and neuropeptides, capable of inhibiting or potentiating ASICs suggests the existence of mechanisms of synaptic modulation that have not yet been fully identified and that could be tuned by new emerging pharmacological compounds with potential therapeutic benefits.
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Affiliation(s)
- Osvaldo D Uchitel
- Departamento de Fisiología, Biología Molecular y Celular "Dr. Héctor Maldonado", Facultad de Ciencias Exactas y Naturales, Instituto de Fisiología, Biología molecular y Neurociencias (IFIBYNE) CONICET, Universidad de Buenos Aires, Ciudad Universitaria, (C1428EGA), Ciudad Autónoma de Buenos Aires, Argentina
| | - Carlota González Inchauspe
- Departamento de Fisiología, Biología Molecular y Celular "Dr. Héctor Maldonado", Facultad de Ciencias Exactas y Naturales, Instituto de Fisiología, Biología molecular y Neurociencias (IFIBYNE) CONICET, Universidad de Buenos Aires, Ciudad Universitaria, (C1428EGA), Ciudad Autónoma de Buenos Aires, Argentina
| | - Carina Weissmann
- Departamento de Fisiología, Biología Molecular y Celular "Dr. Héctor Maldonado", Facultad de Ciencias Exactas y Naturales, Instituto de Fisiología, Biología molecular y Neurociencias (IFIBYNE) CONICET, Universidad de Buenos Aires, Ciudad Universitaria, (C1428EGA), Ciudad Autónoma de Buenos Aires, Argentina
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22
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González-Inchauspe C, Gobetto MN, Uchitel OD. Modulation of acid sensing ion channel dependent protonergic neurotransmission at the mouse calyx of Held. Neuroscience 2019; 439:195-210. [PMID: 31022462 DOI: 10.1016/j.neuroscience.2019.04.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 04/04/2019] [Accepted: 04/05/2019] [Indexed: 11/18/2022]
Abstract
Acid-sensing ion channels (ASICs) regulate synaptic activities and play important roles in neurodegenerative diseases. It has been reported that homomeric ASIC-1a channels are expressed in neurons of the medial nucleus of the trapezoid body (MNTB) of the auditory system in the CNS. During synaptic transmission, acidification of the synaptic cleft presumably due to the co-release of neurotransmitter and H+ from synaptic vesicles activates postsynaptic ASIC-1a channels in mice up to 3 weeks old. This generates synaptic currents (ASIC1a-SCs) that add to the glutamatergic excitatory postsynaptic currents (EPSCs). Here we report that neuromodulators like histamine and natural products like lactate and spermine potentiate ASIC1a-SCs in an additive form such that excitatory ASIC synaptic currents as well as the associated calcium influx become significantly large and physiologically relevant. We show that ASIC1a-SCs enhanced by endogenous neuromodulators are capable of supporting synaptic transmission in the absence of glutamatergic EPSCs. Furthermore, at high frequency stimulation (HFS), ASIC1a-SCs contribute to diminish short term depression (STD) and their contribution is even more relevant at early stages of development. Since ASIC channels are present in almost all types of neurons and synaptic vesicles content is acid, the participation of protons in synaptic transmission and its potentiation by endogenous substances could be a general phenomenon across the central nervous system. This article is part of a Special Issue entitled: Honoring Ricardo Miledi - outstanding neuroscientist of XX-XXI centuries.
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Affiliation(s)
- 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.
| | - 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
| | - 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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23
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Zaremba M, Ruiz-Velasco V. Opioid-Mediated Modulation of Acid-Sensing Ion Channel Currents in Adult Rat Sensory Neurons. Mol Pharmacol 2019; 95:519-527. [PMID: 30808671 DOI: 10.1124/mol.118.114918] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 02/20/2019] [Indexed: 01/10/2023] Open
Abstract
Muscle ischemia, associated with peripheral artery disease (PAD), leads to the release of proinflammatory mediators that decrease extracellular pH and trigger the activation of proton-activated acid-sensing ion channels (ASIC). Claudication pain, linked with low blood flow, can be partially relieved by endogenous opioid peptide release. However, we previously reported that sustained ASIC currents in dorsal root ganglion (DRG) neurons were enhanced by naturally occurring endomorphin-1 and -2 opioid peptides, indicating a role of opioid involvement in hyperalgesia. The present study examined whether clinically employed synthetic (fentanyl, remifentanil) and the semisynthetic opioid (oxycodone) would also potentiate sustained ASIC currents, which arise from ASIC3 channel isoforms. Here, we show that exposure of each opioid to DRG neurons resulted in potentiation of the sustained ASIC currents. On the other hand, the potentiation was not observed in DRG neurons from ASIC3 knockout rats. Further, the enhancement of the ASIC currents was resistant to pertussis toxin treatment, suggesting that Gα i/Gα o G-proteins are not involved. Additionally, the potentiation of sustained ASIC currents was greater in DRG neurons isolated from rats with ligated femoral arteries (a model of PAD). The effect of all three opioids on the transient ASIC peak current was mixed (increase, decrease, no effect). The inhibitory action appears to be mediated by the presence of ASIC1 isoform, while the potentiating effect is primarily due to ASIC3 isoform expression. These findings reveal that, under certain conditions, these three opioids can increase ASIC channel activity, possibly giving rise to opioid-induced hyperalgesia.
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Affiliation(s)
- Malgorzata Zaremba
- Ruiz-Velasco Laboratory, Department of Anesthesiology and Perioperative Medicine, Penn State College of Medicine, Hershey, Pennsylvania
| | - Victor Ruiz-Velasco
- Ruiz-Velasco Laboratory, Department of Anesthesiology and Perioperative Medicine, Penn State College of Medicine, Hershey, Pennsylvania
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24
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Nomura K, Hiyama TY, Sakuta H, Matsuda T, Lin CH, Kobayashi K, Kobayashi K, Kuwaki T, Takahashi K, Matsui S, Noda M. [Na +] Increases in Body Fluids Sensed by Central Na x Induce Sympathetically Mediated Blood Pressure Elevations via H +-Dependent Activation of ASIC1a. Neuron 2018; 101:60-75.e6. [PMID: 30503172 DOI: 10.1016/j.neuron.2018.11.017] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 10/08/2018] [Accepted: 11/08/2018] [Indexed: 02/07/2023]
Abstract
Increases in sodium concentrations ([Na+]) in body fluids elevate blood pressure (BP) by enhancing sympathetic nerve activity (SNA). However, the mechanisms by which information on increased [Na+] is translated to SNA have not yet been elucidated. We herein reveal that sympathetic activation leading to BP increases is not induced by mandatory high salt intakes or the intraperitoneal/intracerebroventricular infusions of hypertonic NaCl solutions in Nax-knockout mice in contrast to wild-type mice. We identify Nax channels expressed in specific glial cells in the organum vasculosum lamina terminalis (OVLT) as the sensors detecting increases in [Na+] in body fluids and show that OVLT neurons projecting to the paraventricular nucleus (PVN) are activated via acid-sensing ion channel 1a (ASIC1a) by H+ ions exported from Nax-positive glial cells. The present results provide an insight into the neurogenic mechanisms responsible for salt-induced BP elevations.
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Affiliation(s)
- Kengo Nomura
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi 444-8787, Japan
| | - Takeshi Y Hiyama
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi 444-8787, Japan; School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan
| | - Hiraki Sakuta
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi 444-8787, Japan; School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan
| | - Takashi Matsuda
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi 444-8787, Japan
| | - Chia-Hao Lin
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi 444-8787, Japan
| | - Kenta Kobayashi
- Section of Viral Vector Development, National Institute for Physiological Sciences, Okazaki, Aichi 444-8585, Japan
| | - Kazuto Kobayashi
- Department of Molecular Genetics, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Tomoyuki Kuwaki
- Department of Physiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8544, Japan
| | - Kunihiko Takahashi
- Department of Biostatistics, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan
| | - Shigeyuki Matsui
- Department of Biostatistics, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan
| | - Masaharu Noda
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi 444-8787, Japan; School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan; Research Center for Cell Biology, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8503, Japan.
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25
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Ilyaskin AV, Diakov A, Korbmacher C, Haerteis S. Bile acids potentiate proton-activated currents in Xenopus laevis oocytes expressing human acid-sensing ion channel (ASIC1a). Physiol Rep 2018; 5:5/3/e13132. [PMID: 28193786 PMCID: PMC5309578 DOI: 10.14814/phy2.13132] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 12/22/2016] [Accepted: 12/22/2016] [Indexed: 01/31/2023] Open
Abstract
Acid‐sensing ion channels (ASICs) are nonvoltage‐gated sodium channels transiently activated by extracellular protons and belong to the epithelial sodium channel (ENaC)/Degenerin (DEG) family of ion channels. Bile acids have been shown to activate two members of this family, the bile acid‐sensitive ion channel (BASIC) and ENaC. To investigate whether bile acids also modulate ASIC function, human ASIC1a was heterologously expressed in Xenopus laevis oocytes. Exposing oocytes to tauro‐conjugated cholic (t‐CA), deoxycholic (t‐DCA), and chenodeoxycholic (t‐CDCA) acid at pH 7.4 did not activate ASIC1a‐mediated whole‐cell currents. However, in ASIC1a expressing oocytes the whole‐cell currents elicited by pH 5.5 were significantly increased in the presence of these bile acids. Single‐channel recordings in outside‐out patches confirmed that t‐DCA enhanced the stimulatory effect of pH 5.5 on ASIC1a channel activity. Interestingly, t‐DCA reduced single‐channel current amplitude by ~15% which suggests an interaction of t‐DCA with a region close to the channel pore. Molecular docking predicted binding of bile acids to the pore region near the degenerin site (G433) in the open conformation of the channel. Site‐directed mutagenesis demonstrated that the amino acid residue G433 is critically involved in the potentiating effect of bile acids on ASIC1a activation by protons.
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Affiliation(s)
- Alexandr V Ilyaskin
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Alexei Diakov
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Christoph Korbmacher
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Silke Haerteis
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
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26
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Ni L, Fang P, Hu ZL, Zhou HY, Chen JG, Wang F, Jin Y. Identification and Function of Acid-sensing Ion Channels in RAW 264.7 Macrophage Cells. Curr Med Sci 2018; 38:436-442. [PMID: 30074209 DOI: 10.1007/s11596-018-1897-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 11/07/2017] [Indexed: 12/20/2022]
Abstract
Activation of acid-sensing ion channels (ASICs) plays an important role in neuroinflammation. Macrophage recruitment to the sites of inflammation is an essential step in host defense. ASIC1 and ASIC3 have been reported to mediate the endocytosis and maturation of bone marrow derived macrophages. However, the expression and inflammation-related functions of ASICs in RAW 264.7 cells, another common macrophage, are still elusive. In the present study, we first demonstrated the presence of ASIC1, ASIC2a and ASIC3 in RAW 264.7 macrophage cell line by using reverse transcriptase polymerase chain reaction (RT-PCR), Western blotting and immunofluorescence experiments. The non-specific ASICs inhibitor amiloride and specific homomeric ASICla blocker PcTxl reduced the production of iNOS and COX-2 by LPS-induced activating RAW 264.7 cells. Furthermore, not only amiloride but also PcTxl inhibited the migration and LPS-induced apoptosis of RAW 264.7 cells. Taken together, our findings suggest that ASICs promote the inflammatory response and apoptosis of RAW 264.7 cells, and ASICs may serve as a potential novel target for immunological disease therapy.
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Affiliation(s)
- Lan Ni
- Department of Pharmacology, Huazhong University of Science and Technology, Wuhan, 430030, China.,Key Laboratory of Neurological Diseases (HUST), Ministry of Education of China, Huazhong University of Science and Technology, Wuhan, 430030, China.,Key Laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Peng Fang
- Department of Pharmacology, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Zhuang-Li Hu
- Department of Pharmacology, Huazhong University of Science and Technology, Wuhan, 430030, China.,Key Laboratory of Neurological Diseases (HUST), Ministry of Education of China, Huazhong University of Science and Technology, Wuhan, 430030, China.,Key Laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hai-Yun Zhou
- Department of Pharmacology, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Jian-Guo Chen
- Department of Pharmacology, Huazhong University of Science and Technology, Wuhan, 430030, China.,Key Laboratory of Neurological Diseases (HUST), Ministry of Education of China, Huazhong University of Science and Technology, Wuhan, 430030, China.,Key Laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province, Huazhong University of Science and Technology, Wuhan, 430030, China.,Institute of Brain Research, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Fang Wang
- Department of Pharmacology, Huazhong University of Science and Technology, Wuhan, 430030, China.,Key Laboratory of Neurological Diseases (HUST), Ministry of Education of China, Huazhong University of Science and Technology, Wuhan, 430030, China.,Key Laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province, Huazhong University of Science and Technology, Wuhan, 430030, China.,Institute of Brain Research, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - You Jin
- Department of Pharmacology, Huazhong University of Science and Technology, Wuhan, 430030, China. .,Key Laboratory of Neurological Diseases (HUST), Ministry of Education of China, Huazhong University of Science and Technology, Wuhan, 430030, China. .,Key Laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province, Huazhong University of Science and Technology, Wuhan, 430030, China.
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27
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Cheng YR, Jiang BY, Chen CC. Acid-sensing ion channels: dual function proteins for chemo-sensing and mechano-sensing. J Biomed Sci 2018; 25:46. [PMID: 29793480 PMCID: PMC5966886 DOI: 10.1186/s12929-018-0448-y] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 05/15/2018] [Indexed: 12/22/2022] Open
Abstract
Background Acid-sensing ion channels (ASICs) are a group of amiloride-sensitive ligand-gated ion channels belonging to the family of degenerin/epithelial sodium channels. ASICs are predominantly expressed in both the peripheral and central nervous system and have been characterized as potent proton sensors to detect extracellular acidification in the periphery and brain. Main body Here we review the recent studies focusing on the physiological roles of ASICs in the nervous system. As the major acid-sensing membrane proteins in the nervous system, ASICs detect tissue acidosis occurring at tissue injury, inflammation, ischemia, stroke, and tumors as well as fatiguing muscle to activate pain-sensing nerves in the periphery and transmit pain signals to the brain. Arachidonic acid and lysophosphocholine have been identified as endogenous non-proton ligands activating ASICs in a neutral pH environment. On the other hand, ASICs are found involved in the tether model mechanotransduction, in which the extracellular matrix and cytoplasmic cytoskeletons act like a gating-spring to tether the mechanically activated ion channels and thus transmit the stimulus force to the channels. Accordingly, accumulating evidence has shown ASICs play important roles in mechanotransduction of proprioceptors, mechanoreceptors and nociceptors to monitor the homoeostatic status of muscle contraction, blood volume, and blood pressure as well as pain stimuli. Conclusion Together, ASICs are dual-function proteins for both chemosensation and mechanosensation involved in monitoring physiological homoeostasis and pathological signals.
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Affiliation(s)
- Yuan-Ren Cheng
- Department of Life Science, National Taiwan University, Taipei, 106, Taiwan.,Institute of Biomedical Sciences, Academia Sinica, 128, Academia Rd. Sec. 2, Taipei, 115, Taiwan
| | - Bo-Yang Jiang
- Department of Life Science, National Taiwan University, Taipei, 106, Taiwan.,Institute of Biomedical Sciences, Academia Sinica, 128, Academia Rd. Sec. 2, Taipei, 115, Taiwan
| | - Chih-Cheng Chen
- Department of Life Science, National Taiwan University, Taipei, 106, Taiwan. .,Institute of Biomedical Sciences, Academia Sinica, 128, Academia Rd. Sec. 2, Taipei, 115, Taiwan. .,Taiwan Mouse Clinic - National Comprehensive Mouse Phenotyping and Drug Testing Center, Academia Sinica, Taipei, 115, Taiwan.
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28
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Husson Z, Smith ESJ. Naked mole-rat cortical neurons are resistant to acid-induced cell death. Mol Brain 2018; 11:26. [PMID: 29739425 PMCID: PMC5941639 DOI: 10.1186/s13041-018-0369-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 04/27/2018] [Indexed: 01/02/2023] Open
Abstract
Regulation of brain pH is a critical homeostatic process and changes in brain pH modulate various ion channels and receptors and thus neuronal excitability. Tissue acidosis, resulting from hypoxia or hypercapnia, can activate various proteins and ion channels, among which acid-sensing ion channels (ASICs) a family of primarily Na+ permeable ion channels, which alongside classical excitotoxicity causes neuronal death. Naked mole-rats (NMRs, Heterocephalus glaber) are long-lived, fossorial, eusocial rodents that display remarkable behavioral/cellular hypoxia and hypercapnia resistance. In the central nervous system, ASIC subunit expression is similar between mouse and NMR with the exception of much lower expression of ASIC4 throughout the NMR brain. However, ASIC function and neuronal sensitivity to sustained acidosis has not been examined in the NMR brain. Here, we show with whole-cell patch-clamp electrophysiology of cultured NMR and mouse cortical and hippocampal neurons that NMR neurons have smaller voltage-gated Na+ channel currents and more hyperpolarized resting membrane potentials. We further demonstrate that acid-mediated currents in NMR neurons are of smaller magnitude than in mouse, and that all currents in both species are reversibly blocked by the ASIC antagonist benzamil. We further demonstrate that NMR neurons show greater resistance to acid-induced cell death than mouse neurons. In summary, NMR neurons show significant cellular resistance to acidotoxicity compared to mouse neurons, contributing factors likely to be smaller ASIC-mediated currents and reduced NaV activity.
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Affiliation(s)
- Zoé Husson
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1PD, UK
| | - Ewan St John Smith
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1PD, UK.
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29
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Wright AJ, Husson ZM, Hu D, Callejo G, Brindle KM, Smith ESJ. Increased hyperpolarized [1- 13 C] lactate production in a model of joint inflammation is not accompanied by tissue acidosis as assessed using hyperpolarized 13 C-labelled bicarbonate. NMR IN BIOMEDICINE 2018; 31:e3892. [PMID: 29380927 PMCID: PMC5887936 DOI: 10.1002/nbm.3892] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 12/01/2017] [Accepted: 12/07/2017] [Indexed: 05/11/2023]
Abstract
Arthritic conditions are a major source of chronic pain. Furthering our understanding of disease mechanisms creates the opportunity to develop more targeted therapeutics. In rheumatoid arthritis (RA), measurements of pH in human synovial fluid suggest that acidosis occurs, but that this is highly variable between individuals. Here we sought to determine if tissue acidosis occurs in a widely used rodent arthritis model: complete Freund's adjuvant (CFA)-induced inflammation. CFA robustly evoked paw and ankle swelling, concomitant with worsening clinical scores over time. We used magnetic resonance spectroscopic imaging of hyperpolarized [1-13 C]pyruvate metabolism to demonstrate that CFA induces an increase in the lactate-to-pyruvate ratio. This increase is indicative of enhanced glycolysis and an increased lactate concentration, as has been observed in the synovial fluid from RA patients, and which was correlated with acidosis. We also measured the 13 CO2 /H13 CO3- ratio, in animals injected with hyperpolarized H13 CO3- , to estimate extracellular tissue pH and showed that despite the apparent increase in glycolytic activity in CFA-induced inflammation there was no accompanying decrease in extracellular pH. The pH was 7.23 ± 0.06 in control paws and 7.32 ± 0.09 in inflamed paws. These results could explain why mice lacking acid-sensing ion channel subunits 1, 2 and 3 do not display any changes in mechanical or thermal hyperalgesia in CFA-induced inflammation.
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Affiliation(s)
- Alan J. Wright
- Cancer Research UK Cambridge InstituteUniversity of Cambridge, Li Ka Shing Centre, Robinson WayCambridgeUK
| | - Zoé M.A. Husson
- Department of PharmacologyUniversity of Cambridge, Tennis Court RoadCambridgeUK
| | - De‐En Hu
- Cancer Research UK Cambridge InstituteUniversity of Cambridge, Li Ka Shing Centre, Robinson WayCambridgeUK
| | - Gerard Callejo
- Department of PharmacologyUniversity of Cambridge, Tennis Court RoadCambridgeUK
| | - Kevin M. Brindle
- Cancer Research UK Cambridge InstituteUniversity of Cambridge, Li Ka Shing Centre, Robinson WayCambridgeUK
- Department of BiochemistryUniversity of Cambridge, Tennis Court RoadCambridgeUK
| | - Ewan St. John Smith
- Department of PharmacologyUniversity of Cambridge, Tennis Court RoadCambridgeUK
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30
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Gonzales EB, Sumien N. Acidity and Acid-Sensing Ion Channels in the Normal and Alzheimer's Disease Brain. J Alzheimers Dis 2018; 57:1137-1144. [PMID: 28211811 DOI: 10.3233/jad-161131] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Alzheimer's disease prevalence has reached epidemic proportion with very few treatment options, which are associated with a multitude of side effects. A potential avenue of research for new therapies are protons, and their associated receptor: acid-sensing ion channels (ASIC). Protons are often overlooked neurotransmitters, and proton-gated currents have been identified in the brain. Furthermore, ASICs have been determined to be crucial for proper brain function. While there is more work to be done, this review is intended to highlight protons as neurotransmitters and their role along with the role of ASICs within physiological functioning of the brain. We will also cover the pathophysiological associations between ASICs and modulators of ASICs. Finally, this review will sum up how the studies of protons, ASICs and their modulators may generate new therapeutic molecules for Alzheimer's disease and other neurodegenerative diseases.
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31
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Sneddon LU. Comparative Physiology of Nociception and Pain. Physiology (Bethesda) 2018; 33:63-73. [DOI: 10.1152/physiol.00022.2017] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 09/18/2017] [Accepted: 09/18/2017] [Indexed: 11/22/2022] Open
Abstract
The study of diverse animal groups allows us to discern the evolution of the neurobiology of nociception. Nociception functions as an important alarm system alerting the individual to potential and actual tissue damage. All animals possess nociceptors, and, in some animal groups, it has been demonstrated that there are consistent physiological mechanisms underpinning the nociceptive system. This review considers the comparative biology of nociception and pain from an evolutionary perspective.
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Affiliation(s)
- Lynne U. Sneddon
- University of Liverpool, Institute of Integrative Biology, The BioScience Building, Liverpool, United Kingdom
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32
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Barygin OI, Komarova MS, Tikhonova TB, Korosteleva AS, Nikolaev MV, Magazanik LG, Tikhonov DB. Complex action of tyramine, tryptamine and histamine on native and recombinant ASICs. Channels (Austin) 2017; 11:648-659. [PMID: 29130788 DOI: 10.1080/19336950.2017.1394557] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Proton-gated channels of the ASIC family are widely distributed in the mammalian brain, and, according to the recent data, participate in synaptic transmission. However, ASIC-mediated currents are small, and special efforts are required to detect them. This prompts the search for endogenous ASIC ligands, which can activate or potentiate these channels. A recent finding of the potentiating action of histamine on recombinant homomeric ASIC1a has directed attention to amine-containing compounds. In the present study, we have analyzed the action of histamine, tyramine, and tryptamine on native and recombinant ASICs. None of the compounds caused potentiation of native ASICs in hippocampal interneurons. Furthermore, when applied simultaneously with channel activation, they produced voltage-dependent inhibition. Experiments on recombinant ASIC1a and ASIC2a allowed for an interpretation of these findings. Histamine and tyramine were found to be inactive on the ASIC2a, while tryptamine demonstrated weak inhibition. However, they induce both voltage-dependent inhibition of open channels and voltage-independent potentiation of closed/desensitized channels on the ASIC1a. We suggest that the presence of an ASIC2a subunit in heteromeric native ASICs prevents potentiation but not inhibition. As a result, the inhibitory action of histamine, which is masked by a strong potentiating effect on the ASIC1a homomers, becomes pronounced in experiments with native ASICs.
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Affiliation(s)
- Oleg I Barygin
- a I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry , Russian Academy of Sciences , Saint-Petersburg , Russia
| | - Margarita S Komarova
- a I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry , Russian Academy of Sciences , Saint-Petersburg , Russia
| | - Tatyana B Tikhonova
- a I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry , Russian Academy of Sciences , Saint-Petersburg , Russia
| | - Anastasiia S Korosteleva
- a I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry , Russian Academy of Sciences , Saint-Petersburg , Russia
| | - Maxim V Nikolaev
- a I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry , Russian Academy of Sciences , Saint-Petersburg , Russia
| | - Lev G Magazanik
- a I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry , Russian Academy of Sciences , Saint-Petersburg , Russia
| | - Denis B Tikhonov
- a I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry , Russian Academy of Sciences , Saint-Petersburg , Russia
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33
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Farrag M, Drobish JK, Puhl HL, Kim JS, Herold PB, Kaufman MP, Ruiz-Velasco V. Endomorphins potentiate acid-sensing ion channel currents and enhance the lactic acid-mediated increase in arterial blood pressure: effects amplified in hindlimb ischaemia. J Physiol 2017; 595:7167-7183. [PMID: 29044528 DOI: 10.1113/jp275058] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 10/13/2017] [Indexed: 12/13/2022] Open
Abstract
KEY POINTS Chronic limb ischaemia, characterized by inflammatory mediator release and a low extracellular pH, leads to acid-sensing ion channel (ASIC) activation and reflexively increases mean arterial pressure; endomorphin release is also increased under inflammatory conditions. We examined the modulation of ASIC currents by endomorphins in sensory neurons from rats with freely perfused and ligated femoral arteries: peripheral artery disease (PAD) model. Endomorphins potentiated sustained ASIC currents in both groups of dorsal root ganglion neurons, independent of mu opioid receptor stimulation or G protein activation. Intra-arterial administration of lactic acid (to simulate exercising muscle and evoke a pressor reflex), endomorphin-2 and naloxone resulted in a significantly greater pressor response than lactic acid alone, while administration of APETx2 inhibited endomorphin's enhancing effect in both groups. These results suggest a novel role for endomorphins in modulating ASIC function to effect lactic acid-mediated reflex increase in arterial pressure in patients with PAD. ABSTRACT Chronic muscle ischaemia leads to accumulation of lactic acid and other inflammatory mediators with a subsequent drop in interstitial pH. Acid-sensing ion channels (ASICs), expressed in thin muscle afferents, sense the decrease in pH and evoke a pressor reflex known to increase mean arterial pressure. The naturally occurring endomorphins are also released by primary afferents under ischaemic conditions. We examined whether high affinity mu opioid receptor (MOR) agonists, endomorphin-1 (E-1) and -2 (E-2), modulate ASIC currents and the lactic acid-mediated pressor reflex. In rat dorsal root ganglion (DRG) neurons, exposure to E-2 in acidic solutions significantly potentiated ASIC currents when compared to acidic solutions alone. The potentiation was significantly greater in DRG neurons isolated from rats whose femoral arteries were ligated for 72 h. Sustained ASIC current potentiation was also observed in neurons pretreated with pertussis toxin, an uncoupler of G proteins and MOR. The endomorphin-mediated potentiation was a result of a leftward shift of the activation curve to higher pH values and a slight shift of the inactivation curve to lower pH values. Intra-arterial co-administration of lactic acid and E-2 led to a significantly greater pressor reflex than lactic acid alone in the presence of naloxone. Finally, E-2 effects were inhibited by pretreatment with the ASIC3 blocker APETx2 and enhanced by pretreatment with the ASIC1a blocker psalmotoxin-1. These findings have uncovered a novel role of endomorphins by which the opioids can enhance the lactic acid-mediated reflex increase in arterial pressure that is MOR stimulation-independent and APETx2-sensitive.
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Affiliation(s)
- Mohamed Farrag
- Department of Anesthesiology and Perioperative Medicine, Penn State College of Medicine, Hershey, PA, USA
| | - Julie K Drobish
- Department of Anesthesiology and Perioperative Medicine, Penn State College of Medicine, Hershey, PA, USA
| | - Henry L Puhl
- Department of Anesthesiology and Perioperative Medicine, Penn State College of Medicine, Hershey, PA, USA
| | - Joyce S Kim
- Department of Anesthesiology and Perioperative Medicine, Penn State College of Medicine, Hershey, PA, USA
| | - Paul B Herold
- Department of Anesthesiology and Perioperative Medicine, Penn State College of Medicine, Hershey, PA, USA
| | - Marc P Kaufman
- Department of Anesthesiology and Perioperative Medicine, Penn State College of Medicine, Hershey, PA, USA
| | - Victor Ruiz-Velasco
- Department of Anesthesiology and Perioperative Medicine, Penn State College of Medicine, Hershey, PA, USA
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Acid-Sensing Ion Channels as Potential Therapeutic Targets in Neurodegeneration and Neuroinflammation. Mediators Inflamm 2017; 2017:3728096. [PMID: 29056828 PMCID: PMC5625748 DOI: 10.1155/2017/3728096] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Revised: 07/29/2017] [Accepted: 08/13/2017] [Indexed: 12/21/2022] Open
Abstract
Acid-sensing ion channels (ASICs) are a family of proton-sensing channels that are voltage insensitive, cation selective (mostly permeable to Na+), and nonspecifically blocked by amiloride. Derived from 5 genes (ACCN1-5), 7 subunits have been identified, 1a, 1b, 2a, 2b, 3, 4, and 5, that are widely expressed in the peripheral and central nervous system as well as other tissues. Over the years, different studies have shown that activation of these channels is linked to various physiological and pathological processes, such as memory, learning, fear, anxiety, ischemia, and multiple sclerosis to name a few, so their potential as therapeutic targets is increasing. This review focuses on recent advances that have helped us to better understand the role played by ASICs in different pathologies related to neurodegenerative diseases, inflammatory processes, and pain.
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35
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Osmakov DI, Koshelev SG, Andreev YA, Kozlov SA. Endogenous Isoquinoline Alkaloids Agonists of Acid-Sensing Ion Channel Type 3. Front Mol Neurosci 2017; 10:282. [PMID: 28955199 PMCID: PMC5602355 DOI: 10.3389/fnmol.2017.00282] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 08/21/2017] [Indexed: 12/21/2022] Open
Abstract
Acid-sensing ion channels (ASICs) ASIC3 expressed mainly in peripheral sensory neurons play an important role in pain perception and inflammation development. In response to acidic stimuli, they can generate a unique biphasic current. At physiological pH 7.4, human ASIC3 isoform (hASIC3) is desensitized and able to generate only a sustained current. We found endogenous isoquinoline alkaloids (EIAs), which restore hASIC3 from desensitization and recover the transient component of the current. Similarly, rat ASIC3 isoform (rASIC3) can also be restored from desensitization (at pH < 7.0) by EIAs with the same potency. At physiological pH and above, EIAs at high concentrations were able to effectively activate hASIC3 and rASIC3. Thus, we found first endogenous agonists of ASIC3 channels that could both activate and prevent or reverse desensitization of the channel. The decrease of EIA levels could be suggested as a novel therapeutic strategy for treatment of pain and inflammation.
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Affiliation(s)
- Dmitry I Osmakov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of SciencesMoscow, Russia.,Institute of Molecular Medicine, Sechenov First Moscow State Medical UniversityMoscow, Russia
| | - Sergey G Koshelev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of SciencesMoscow, Russia
| | - Yaroslav A Andreev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of SciencesMoscow, Russia.,Institute of Molecular Medicine, Sechenov First Moscow State Medical UniversityMoscow, Russia
| | - Sergey A Kozlov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of SciencesMoscow, Russia
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36
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Rash LD. Acid-Sensing Ion Channel Pharmacology, Past, Present, and Future …. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2017; 79:35-66. [PMID: 28528673 DOI: 10.1016/bs.apha.2017.02.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
pH is one of the most strictly controlled parameters in mammalian physiology. An extracellular pH of ~7.4 is crucial for normal physiological processes, and perturbations to this have profound effects on cell function. Acidic microenvironments occur in many physiological and pathological conditions, including inflammation, bone remodeling, ischemia, trauma, and intense synaptic activity. Cells exposed to these conditions respond in different ways, from tumor cells that thrive to neurons that are either suppressed or hyperactivated, often fatally. Acid-sensing ion channels (ASICs) are primary pH sensors in mammals and are expressed widely in neuronal and nonneuronal cells. There are six main subtypes of ASICs in rodents that can form homo- or heteromeric channels resulting in many potential combinations. ASICs are present and activated under all of the conditions mentioned earlier, suggesting that they play an important role in how cells respond to acidosis. Compared to many other ion channel families, ASICs were relatively recently discovered-1997-and there is a substantial lack of potent, subtype-selective ligands that can be used to elucidate their structural and functional properties. In this chapter I cover the history of ASIC channel pharmacology, which began before the proteins were even identified, and describe the current arsenal of tools available, their limitations, and take a glance into the future to predict from where new tools are likely to emerge.
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Affiliation(s)
- Lachlan D Rash
- School of Biomedical Sciences, The University of Queensland, St Lucia, QLD, Australia.
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37
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Eag1 K + Channel: Endogenous Regulation and Functions in Nervous System. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:7371010. [PMID: 28367272 PMCID: PMC5358448 DOI: 10.1155/2017/7371010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 12/27/2016] [Accepted: 01/31/2017] [Indexed: 02/04/2023]
Abstract
Ether-à-go-go1 (Eag1, Kv10.1, KCNH1) K+ channel is a member of the voltage-gated K+ channel family mainly distributed in the central nervous system and cancer cells. Like other types of voltage-gated K+ channels, the EAG1 channels are regulated by a variety of endogenous signals including reactive oxygen species, rendering the EAG1 to be in the redox-regulated ion channel family. The role of EAG1 channels in tumor development and its therapeutic significance have been well established. Meanwhile, the importance of hEAG1 channels in the nervous system is now increasingly appreciated. The present review will focus on the recent progress on the channel regulation by endogenous signals and the potential functions of EAG1 channels in normal neuronal signaling as well as neurological diseases.
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Boscardin E, Alijevic O, Hummler E, Frateschi S, Kellenberger S. The function and regulation of acid-sensing ion channels (ASICs) and the epithelial Na(+) channel (ENaC): IUPHAR Review 19. Br J Pharmacol 2016; 173:2671-701. [PMID: 27278329 DOI: 10.1111/bph.13533] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 05/19/2016] [Accepted: 06/02/2016] [Indexed: 12/30/2022] Open
Abstract
Acid-sensing ion channels (ASICs) and the epithelial Na(+) channel (ENaC) are both members of the ENaC/degenerin family of amiloride-sensitive Na(+) channels. ASICs act as proton sensors in the nervous system where they contribute, besides other roles, to fear behaviour, learning and pain sensation. ENaC mediates Na(+) reabsorption across epithelia of the distal kidney and colon and of the airways. ENaC is a clinically used drug target in the context of hypertension and cystic fibrosis, while ASIC is an interesting potential target. Following a brief introduction, here we will review selected aspects of ASIC and ENaC function. We discuss the origin and nature of pH changes in the brain and the involvement of ASICs in synaptic signalling. We expose how in the peripheral nervous system, ASICs cover together with other ion channels a wide pH range as proton sensors. We introduce the mechanisms of aldosterone-dependent ENaC regulation and the evidence for an aldosterone-independent control of ENaC activity, such as regulation by dietary K(+) . We then provide an overview of the regulation of ENaC by proteases, a topic of increasing interest over the past few years. In spite of the profound differences in the physiological and pathological roles of ASICs and ENaC, these channels share many basic functional and structural properties. It is likely that further research will identify physiological contexts in which ASICs and ENaC have similar or overlapping roles.
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Affiliation(s)
- Emilie Boscardin
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Omar Alijevic
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Edith Hummler
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
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MacLean DM, Jayaraman V. Acid-sensing ion channels are tuned to follow high-frequency stimuli. J Physiol 2016; 594:2629-45. [PMID: 26931316 DOI: 10.1113/jp271915] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 02/27/2016] [Indexed: 01/26/2023] Open
Abstract
KEY POINTS Acid-sensing ion channels (ASICs) act as neurotransmitter receptors by responding to synaptic cleft acidification. We investigated how ASIC1a homomers and ASIC1a/2a heteromers respond to brief stimuli, jumping from pH 8.0 to 5.0, approximating the time course of neurotransmitter in the cleft. We find that ASICs deactivate surprisingly fast in response to such brief stimuli from pH 8.0 to 5.0, whereas they desensitize comparatively slowly to prolonged activation. The combination of unusually fast deactivation with slow desensitzation enables recombinant ASIC1a homomers and ASIC1a/2a heteromers, as well as native ASICs of sensory neurons, to follow trains of such brief pH 8.0 to 5.0 stimuli at high frequencies. This capacity for high-frequency signalling persists under a physiological pH of 7.4 with ASIC1a/2a heteromers, suggesting that they may sustain postsynaptic responses when other receptors desensitize. ABSTRACT The neurotransmitter-gated ion channels that underlie rapid synaptic transmission are often subjected to bursts of very brief neurotransmitter release at high frequencies. When challenged with such short duration high-frequency stimuli, neurotransmitter-gated ion channels generally exhibit the common response of desensitization. Recently, acid-sensing ion channels (ASICs) were shown to act as neurotransmitter-gated ion channels because postsynaptic ASICs can be activated by the transient acidification of the synaptic cleft accompanying neurotransmission. In the present study, we examined the responses of recombinant ASIC1a homomers, ASIC1a/2a heteromers and native ASICs from sensory neurons to 1 ms acidification stimuli, switching from pH 8.0 to 5.0, as either single pulses or trains of pulses at physiologically relevant frequencies. We found that ASIC deactivation is extremely fast and, in contrast to most other neurotransmitter-gated ion channels, ASICs show no desensitization during high-frequency stimulus trains under these conditions. We also found that accelerating ASIC desensitization by anion substitution can induce depression during high-frequency trains. When using a baseline physiological pH of 7.4, the ASIC1a responses were too small to reliably measure, presumably as a result of steady-state desensitization. However, ASIC1a/2 heteromers gave robust responses when using a baseline pH of 7.4 and were also able to sustain these responses during high-frequency stimulus trains. In conclusion, we report that the slow desensitization and fast deactivation of ASIC1a/2a heteromers enables them to sustain postsynaptic responses to bursts at high frequencies at a physiological pH that may desensitize other receptors.
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Affiliation(s)
- David M MacLean
- Center for Membrane Biology, Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX, USA
| | - Vasanthi Jayaraman
- Center for Membrane Biology, Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX, USA
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Marra S, Ferru-Clément R, Breuil V, Delaunay A, Christin M, Friend V, Sebille S, Cognard C, Ferreira T, Roux C, Euller-Ziegler L, Noel J, Lingueglia E, Deval E. Non-acidic activation of pain-related Acid-Sensing Ion Channel 3 by lipids. EMBO J 2016; 35:414-28. [PMID: 26772186 DOI: 10.15252/embj.201592335] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 12/07/2015] [Indexed: 12/21/2022] Open
Abstract
Extracellular pH variations are seen as the principal endogenous signal that triggers activation of Acid-Sensing Ion Channels (ASICs), which are basically considered as proton sensors, and are involved in various processes associated with tissue acidification. Here, we show that human painful inflammatory exudates, displaying non-acidic pH, induce a slow constitutive activation of human ASIC3 channels. This effect is largely driven by lipids, and we identify lysophosphatidylcholine (LPC) and arachidonic acid (AA) as endogenous activators of ASIC3 in the absence of any extracellular acidification. The combination of LPC and AA evokes robust depolarizing current in DRG neurons at physiological pH 7.4, increases nociceptive C-fiber firing, and induces pain behavior in rats, effects that are all prevented by ASIC3 blockers. Lipid-induced pain is also significantly reduced in ASIC3 knockout mice. These findings open new perspectives on the roles of ASIC3 in the absence of tissue pH variation, as well as on the contribution of those channels to lipid-mediated signaling.
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Affiliation(s)
- Sébastien Marra
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275, Valbonne, France Université de Nice Sophia Antipolis, UMR 7275, Valbonne, France LabEx Ion Channel Science and Therapeutics, Valbonne, France
| | - Romain Ferru-Clément
- CNRS, Laboratoire de Signalisation et Transports Ioniques Membranaires (STIM), ERL 7368, Poitiers Cedex 9, France Université de Poitiers, ERL 7368, Poitiers Cedex 9, France
| | | | - Anne Delaunay
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275, Valbonne, France Université de Nice Sophia Antipolis, UMR 7275, Valbonne, France LabEx Ion Channel Science and Therapeutics, Valbonne, France
| | - Marine Christin
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275, Valbonne, France Université de Nice Sophia Antipolis, UMR 7275, Valbonne, France LabEx Ion Channel Science and Therapeutics, Valbonne, France
| | - Valérie Friend
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275, Valbonne, France Université de Nice Sophia Antipolis, UMR 7275, Valbonne, France LabEx Ion Channel Science and Therapeutics, Valbonne, France
| | - Stéphane Sebille
- CNRS, Laboratoire de Signalisation et Transports Ioniques Membranaires (STIM), ERL 7368, Poitiers Cedex 9, France Université de Poitiers, ERL 7368, Poitiers Cedex 9, France
| | - Christian Cognard
- CNRS, Laboratoire de Signalisation et Transports Ioniques Membranaires (STIM), ERL 7368, Poitiers Cedex 9, France Université de Poitiers, ERL 7368, Poitiers Cedex 9, France
| | - Thierry Ferreira
- CNRS, Laboratoire de Signalisation et Transports Ioniques Membranaires (STIM), ERL 7368, Poitiers Cedex 9, France Université de Poitiers, ERL 7368, Poitiers Cedex 9, France
| | | | | | - Jacques Noel
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275, Valbonne, France Université de Nice Sophia Antipolis, UMR 7275, Valbonne, France LabEx Ion Channel Science and Therapeutics, Valbonne, France
| | - Eric Lingueglia
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275, Valbonne, France Université de Nice Sophia Antipolis, UMR 7275, Valbonne, France LabEx Ion Channel Science and Therapeutics, Valbonne, France
| | - Emmanuel Deval
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275, Valbonne, France Université de Nice Sophia Antipolis, UMR 7275, Valbonne, France LabEx Ion Channel Science and Therapeutics, Valbonne, France
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Radu BM, Banciu A, Banciu DD, Radu M. Acid-Sensing Ion Channels as Potential Pharmacological Targets in Peripheral and Central Nervous System Diseases. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2015; 103:137-67. [PMID: 26920689 DOI: 10.1016/bs.apcsb.2015.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Acid-sensing ion channels (ASICs) are widely expressed in the body and represent good sensors for detecting protons. The pH drop in the nervous system is equivalent to ischemia and acidosis, and ASICs are very good detectors in discriminating slight changes in acidity. ASICs are important pharmacological targets being involved in a variety of pathophysiological processes affecting both the peripheral nervous system (e.g., peripheral pain, diabetic neuropathy) and the central nervous system (e.g., stroke, epilepsy, migraine, anxiety, fear, depression, neurodegenerative diseases, etc.). This review discusses the role played by ASICs in different pathologies and the pharmacological agents acting on ASICs that might represent promising drugs. As the majority of above-mentioned pathologies involve not only neuronal dysfunctions but also microvascular alterations, in the next future, ASICs may be also considered as potential pharmacological targets at the vasculature level. Perspectives and limitations in the use of ASICs antagonists and modulators as pharmaceutical agents are also discussed.
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Affiliation(s)
- Beatrice Mihaela Radu
- Department of Neurological and Movement Sciences, Section of Anatomy and Histology, University of Verona, Verona, Italy; Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Adela Banciu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Daniel Dumitru Banciu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Mihai Radu
- Department of Neurological and Movement Sciences, Section of Anatomy and Histology, University of Verona, Verona, Italy; Department of Life and Environmental Physics, 'Horia Hulubei' National Institute for Physics and Nuclear Engineering, Magurele, Romania.
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Gu H, Fang YJ, Liu DD, Chen P, Mei YA. cAMP/PKA Pathways and S56 Phosphorylation Are Involved in AA/PGE2-Induced Increases in rNaV1.4 Current. PLoS One 2015; 10:e0140715. [PMID: 26485043 PMCID: PMC4618696 DOI: 10.1371/journal.pone.0140715] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 09/28/2015] [Indexed: 12/19/2022] Open
Abstract
Arachidonic acid (AA) and its metabolites are important second messengers for ion channel modulation. The effects of extracellular application of AA and its non-metabolized analogue on muscle rNaV1.4 Na+ current has been studied, but little is known about the effects of intracellular application of AA on this channel isoform. Here, we report that intracellular application of AA significantly augmented the rNaV1.4 current peak without modulating the steady-state activation and inactivation properties of the rNaV1.4 channel. These results differed from the effects of extracellular application of AA on rNaV1.4 current. The effects of intracellular AA were mimicked by prostaglandin E2 but not eicosatetraynoic acid (ETYA), the non-metabolized analogue of AA, and were eliminated by treatment with cyclooxygenase inhibitors, flufenamic acid, or indomethacin. AA/PGE2-induced activation of rNaV1.4 channels was mimicked by a cAMP analogue (db-cAMP) and eliminated by a PKA inhibitor, PKAi. Furthermore, inhibition of EP2 and EP4 (PGE2 receptors) with AH6809 and AH23848 reduced the intracellular AA/PGE2-induced increase of rNaV1.4 current. Two mutated channels, rNaV1.4S56A and rNaV1.4T21A, were designed to investigate the role of predicted phosphorylation sites in the AA/PGE2–mediated regulation of rNaV1.4 currents. In rNaV1.4S56A, the effects of intracellular db-cAMP, AA, and PGE2 were significantly reduced. The results of the present study suggest that intracellular AA augments rNaV1.4 current by PGE2/EP receptor-mediated activation of the cAMP/PKA pathway, and that the S56 residue on the channel protein is important for this process.
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Affiliation(s)
- Hua Gu
- School of Life Science and Technology, Tongji University, Shanghai 200092, PR China
- * E-mail: (HG); (YAM)
| | - Yan-Jia Fang
- School of Life Sciences, Institute of Brain Science and State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200433, PR China
| | - Dong-Dong Liu
- School of Life Sciences, Institute of Brain Science and State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200433, PR China
| | - Ping Chen
- School of Life Science and Technology, Tongji University, Shanghai 200092, PR China
| | - Yan-Ai Mei
- School of Life Sciences, Institute of Brain Science and State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200433, PR China
- * E-mail: (HG); (YAM)
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43
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Osmakov DI, Andreev YA, Kozlov SA. Acid-sensing ion channels and their modulators. BIOCHEMISTRY (MOSCOW) 2015; 79:1528-45. [PMID: 25749163 DOI: 10.1134/s0006297914130069] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
According to a modern look acid-sensing ion channels (ASICs) are one of the most important receptors that perceive pH change in the body. ASICs represent proton-gated Na+-selective channels, which are expressed in neurons of the central and peripheral nervous system. These channels are attracting attention of researchers around the world, as they are involved in various physiological processes in the body. Drop of pH may occur in tissues in norm (e.g. the accumulation of lactic acid, the release of protons upon ATP hydrolysis) and pathology (inflammation, ischemic stroke, tissue damage and seizure). These processes are accompanied by unpleasant pain sensations, which may be short-lived or can lead to chronic inflammatory diseases. Modulators of ASIC channels activity are potential candidates for new effective analgesic and neuroprotection drugs. This review summarizes available information about structure, function, and physiological role of ASIC channels. In addition a description of all known ligands of these channels and their practical relevance is provided.
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Affiliation(s)
- D I Osmakov
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia.
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44
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Baron A, Lingueglia E. Pharmacology of acid-sensing ion channels – Physiological and therapeutical perspectives. Neuropharmacology 2015; 94:19-35. [DOI: 10.1016/j.neuropharm.2015.01.005] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 12/15/2014] [Accepted: 01/07/2015] [Indexed: 12/29/2022]
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Proton-induced currents in substantia gelatinosa neurons of the rat trigeminal subnucleus caudalis. Eur J Pharmacol 2015; 762:18-25. [PMID: 25962663 DOI: 10.1016/j.ejphar.2015.04.052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Revised: 04/30/2015] [Accepted: 04/30/2015] [Indexed: 11/20/2022]
Abstract
Acid-sensing ion channels (ASICs) are widely expressed in both the peripheral and central nervous system, and contribute to the modulation of central nociceptive transmission under both physiological and pathophysiological conditions. In this study, we characterized the proton-induced membrane currents in acutely isolated rat substantia gelatinosa (SG) neurons of the trigeminal subnucleus caudalis using the whole cell patch-clamp technique. Exposure to acidic conditions (pH<6.5) induced the inward currents in a pH-dependent manner. Amiloride, a general ASIC antagonist, significantly blocked the proton-induced currents in a non-competitive manner. The pH 6.0-induced membrane current (IpH6.0) was greatly attenuated in the Na(+)-free external solution, and the reversal potential of the proton-induced currents was similar to the theoretical Na(+) equilibrium potential. The IpH6.0 was reciprocally potentiated by a lower extracellular Ca(2+) concentration. The modulation of IpH6.0 by divalent cations and other modulators suggests that the proton-induced currents are mediated by multiple types of ASIC subunits, including ASIC1a and ASIC2a. Multi-cell RT-PCR analysis revealed that SG neurons express these subunits. Exposure to a pH 6.0 solution directly depolarized the membrane potential, and generated a burst of action potentials in a current-clamp mode. This acidic pH-induced depolarization was significantly blocked by amiloride. The present results suggest that ASICs expressed on SG neurons play important roles in the regulation of nociceptive transmission from the orofacial tissues.
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46
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Differential regulation of proton-sensitive ion channels by phospholipids: a comparative study between ASICs and TRPV1. PLoS One 2015; 10:e0122014. [PMID: 25781982 PMCID: PMC4362947 DOI: 10.1371/journal.pone.0122014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 02/05/2015] [Indexed: 12/31/2022] Open
Abstract
Protons are released in pain-generating pathological conditions such as inflammation, ischemic stroke, infection, and cancer. During normal synaptic activities, protons are thought to play a role in neurotransmission processes. Acid-sensing ion channels (ASICs) are typical proton sensors in the central nervous system (CNS) and the peripheral nervous system (PNS). In addition to ASICs, capsaicin- and heat-activated transient receptor potential vanilloid 1 (TRPV1) channels can also mediate proton-mediated pain signaling. In spite of their importance in perception of pH fluctuations, the regulatory mechanisms of these proton-sensitive ion channels still need to be further investigated. Here, we compared regulation of ASICs and TRPV1 by membrane phosphoinositides, which are general cofactors of many receptors and ion channels. We observed that ASICs do not require membrane phosphatidylinositol 4-phosphate (PI(4)P) or phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) for their function. However, TRPV1 currents were inhibited by simultaneous breakdown of PI(4)P and PI(4,5)P2. By using a novel chimeric protein, CF-PTEN, that can specifically dephosphorylate at the D3 position of phosphatidylinositol 3,4,5-trisphosphate (PI(3,4,5)P3), we also observed that neither ASICs nor TRPV1 activities were altered by depletion of PI(3,4,5)P3 in intact cells. Finally, we compared the effects of arachidonic acid (AA) on two proton-sensitive ion channels. We observed that AA potentiates the currents of both ASICs and TRPV1, but that they have different recovery aspects. In conclusion, ASICs and TRPV1 have different sensitivities toward membrane phospholipids, such as PI(4)P, PI(4,5)P2, and AA, although they have common roles as proton sensors. Further investigation about the complementary roles and respective contributions of ASICs and TRPV1 in proton-mediated signaling is necessary.
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Deval E, Lingueglia E. Acid-Sensing Ion Channels and nociception in the peripheral and central nervous systems. Neuropharmacology 2015; 94:49-57. [PMID: 25724084 DOI: 10.1016/j.neuropharm.2015.02.009] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 02/10/2015] [Accepted: 02/12/2015] [Indexed: 11/17/2022]
Abstract
Since their molecular cloning in the late 90's, Acid-Sensing Ion Channels (ASICs) have been shown to be involved in many aspects of nociception, both in peripheral and central neurons. In rodents, the combination of specific or non-specific pharmacological modulators of ASICs, together with in vivo knockdown and/or knockout animals has revealed their contribution to the detection, the modulation and the sensitization of the pain message by primary and secondary sensory neurons. Functional ASICs are homo or heterotrimers of different homologous subunits (ASIC1-3). Channels containing ASIC3 or ASIC1 subunits, appear to be important in peripheral nociceptors, where they are subject to intense regulation, while ASIC1a-containing channels also have a prominent role in central neurons, including spinal cord neurons that modulate and transmit the pain signal to the brain. In humans, experiments performed in healthy volunteers using drugs already used in the clinic and acting as poorly-selective inhibitors of ASICs, together with recent in vitro data obtained from stem cell-derived sensory neurons both support a role for these channels in nociception. These data thus suggest a real translational potential in the development of inhibitory strategies of ASICs for the treatment of pain. This article is part of the Special Issue entitled 'Acid-Sensing Ion Channels in the Nervous System'.
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Affiliation(s)
- Emmanuel Deval
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275, 06560 Valbonne, France; Université de Nice Sophia Antipolis, UMR 7275, 06560 Valbonne, France; LabEx Ion Channel Science and Therapeutics, UMR 7275, 06560 Valbonne, France.
| | - Eric Lingueglia
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275, 06560 Valbonne, France; Université de Nice Sophia Antipolis, UMR 7275, 06560 Valbonne, France; LabEx Ion Channel Science and Therapeutics, UMR 7275, 06560 Valbonne, France
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Lei Z, Li X, Wang G, Fei J, Meng T, Zhang X, Yu J, Yu J, Li J. Inhibition of acid-sensing ion channel currents by propofol in rat dorsal root ganglion neurons. Clin Exp Pharmacol Physiol 2014; 41:295-300. [PMID: 24552301 DOI: 10.1111/1440-1681.12215] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2013] [Revised: 01/16/2014] [Accepted: 02/09/2014] [Indexed: 11/30/2022]
Abstract
Acid-sensing ion channels (ASICs), part of the epithelial sodium channel/degenerin family, are activated by extracellular protons. The ASICs play a significant role in the acidosis-mediated perception of pain. The anaesthetic agent propofol also exerts antinociceptive effects, but the underlying mechanisms for this effect are not clear. We used whole-cell patch clamping to investigate the effect of propofol on proton-gated currents in: (i) rat dorsal root ganglion (DRG) neurons; and (ii) HEK293 cells transfected with either ASIC1a or ASIC3. Propofol inhibited the amplitude of proton-gated currents in DRG neurons, but did not change the sensitivity of ASICs to H(+). Notably, propofol altered acid-evoked excitability of rat DRG neurons and decreased the number of action potentials induced by acid stimuli. In addition, we demonstrated that propofol inhibited ASICs by directly binding with these channels in HEK293 cells. These results suggest that propofol inhibits proton-gated currents in DRG neurons and that inhibition of proton-gated currents explains, in part, the antinociceptive effects of propofol in primary afferent neurons.
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Affiliation(s)
- Zhen Lei
- Department of Anesthesiology, Qilu Hospital, Shandong University, Jinan, Shandong, China
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Kellenberger S, Schild L. International Union of Basic and Clinical Pharmacology. XCI. Structure, Function, and Pharmacology of Acid-Sensing Ion Channels and the Epithelial Na+ Channel. Pharmacol Rev 2014; 67:1-35. [DOI: 10.1124/pr.114.009225] [Citation(s) in RCA: 193] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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50
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Tikhonova TB, Nagaeva EI, Barygin OI, Potapieva NN, Bolshakov KV, Tikhonov DB. Monoamine NMDA receptor channel blockers inhibit and potentiate native and recombinant proton-gated ion channels. Neuropharmacology 2014; 89:1-10. [PMID: 25196733 DOI: 10.1016/j.neuropharm.2014.08.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 07/15/2014] [Accepted: 08/26/2014] [Indexed: 10/24/2022]
Abstract
Acid-sensing ion channels (ASICs) are widely distributed in the peripheral and central nervous system. Although they are involved in many physiological functions, the actual processes that activate ASICs remain unclear. This is particularly true for brain ASICs, which produce only a transient response to a fast drop in pH and cannot mediate sustained current. Therefore, the search for ASIC inhibitors and, especially, potentiators/activators is important. We report that NMDA receptor channel blockers with a comparatively simple structure (9-aminoacridine, memantine, IEM-2117 and IEM-1921) potentiate and/or inhibit ASICs in submillimolar concentrations. The experiments were performed using the patch clamp technique on native ASICs from rat hippocampal interneurons and recombinant ASICs of different subunit compositions expressed in CHO cells. Native ASICs were potentiated by IEM-1921 and IEM-2117, and inhibited by memantine and 9-aminoacridine. Homomeric ASIC1a were inhibited by memantine, IEM-2117 and 9-aminoacridine while IEM-1921 was ineffective. In contrast, homomeric ASIC2a were potentiated by IEM-2117, memantine and IEM-1921, whereas 9-aminoacridine was inactive. The compounds caused a complex effect on ASIC3. 9-aminoacridine and IEM-1921 potentiated the steady-state response of ASIC3 and inhibited the peak component. IEM-2117 not only potentiated ASIC3-mediated currents caused by acidification but also evoked steady-state currents at neutral pH. Our results demonstrate that, depending on the subunit composition, ASICs can be activated or inhibited by simple compounds that possess only amino group and aromatic/hydrophobic moieties. This opens up the possibility to search for new ASIC modulators among a number of endogenous ligands.
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Affiliation(s)
- Tatiana B Tikhonova
- I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223, 44 Thorez pr., St.Petersburg, Russia
| | - Elina I Nagaeva
- I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223, 44 Thorez pr., St.Petersburg, Russia
| | - Oleg I Barygin
- I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223, 44 Thorez pr., St.Petersburg, Russia
| | - Natalia N Potapieva
- I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223, 44 Thorez pr., St.Petersburg, Russia
| | - Konstantin V Bolshakov
- I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223, 44 Thorez pr., St.Petersburg, Russia
| | - Denis B Tikhonov
- I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223, 44 Thorez pr., St.Petersburg, Russia.
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