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Hung CH, Chin Y, Fong YO, Lee CH, Han DS, Lin JH, Sun WH, Chen CC. Acidosis-related pain and its receptors as targets for chronic pain. Pharmacol Ther 2023; 247:108444. [PMID: 37210007 DOI: 10.1016/j.pharmthera.2023.108444] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/24/2023] [Accepted: 05/15/2023] [Indexed: 05/22/2023]
Abstract
Sensing acidosis is an important somatosensory function in responses to ischemia, inflammation, and metabolic alteration. Accumulating evidence has shown that acidosis is an effective factor for pain induction and that many intractable chronic pain diseases are associated with acidosis signaling. Various receptors have been known to detect extracellular acidosis and all express in the somatosensory neurons, such as acid sensing ion channels (ASIC), transient receptor potential (TRP) channels and proton-sensing G-protein coupled receptors. In addition to sense noxious acidic stimulation, these proton-sensing receptors also play a vital role in pain processing. For example, ASICs and TRPs are involved in not only nociceptive activation but also anti-nociceptive effects as well as some other non-nociceptive pathways. Herein, we review recent progress in probing the roles of proton-sensing receptors in preclinical pain research and their clinical relevance. We also propose a new concept of sngception to address the specific somatosensory function of acid sensation. This review aims to connect these acid-sensing receptors with basic pain research and clinical pain diseases, thus helping with better understanding the acid-related pain pathogenesis and their potential therapeutic roles via the mechanism of acid-mediated antinociception.
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Affiliation(s)
- Chih-Hsien Hung
- Department of Neurology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yin Chin
- Department of Life Science & Institute of Genome Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yi-On Fong
- Department of Neurology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Cheng-Han Lee
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Der-Shen Han
- Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, Bei-Hu Branch, Taipei, Taiwan
| | - Jiann-Her Lin
- Neuroscience Research Center, Taipei Medical University, Taipei, Taiwan; Department of Neurosurgery, Taipei Medical University Hospital, Taipei, Taiwan
| | - Wei-Hsin Sun
- Department of Life Science & Institute of Genome Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chih-Cheng Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan; Neuroscience Research Center, Taipei Medical University, Taipei, Taiwan; Neuroscience Program of Academia Sinica, Academia Sinica, Taipei, Taiwan.
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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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Lai K, Song XL, Shi HS, Qi X, Li CY, Fang J, Wang F, Maximyuk O, Krishtal O, Xu TL, Li XY, Ni K, Li WP, Shi HB, Wang LY, Yin SK. Bilirubin enhances the activity of ASIC channels to exacerbate neurotoxicity in neonatal hyperbilirubinemia in mice. Sci Transl Med 2020; 12:12/530/eaax1337. [PMID: 32051225 DOI: 10.1126/scitranslmed.aax1337] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 08/03/2019] [Accepted: 12/10/2019] [Indexed: 12/24/2022]
Abstract
Neonatal hyperbilirubinemia is a common clinical condition that can lead to brain encephalopathy, particularly when concurrent with acidosis due to infection, ischemia, and hypoxia. The prevailing view is that acidosis increases the permeability of the blood-brain barrier to bilirubin and exacerbates its neurotoxicity. In this study, we found that the concentration of the cell death marker, lactate dehydrogenase (LDH) in cerebrospinal fluid (CSF), is elevated in infants with both hyperbilirubinemia and acidosis and showed stronger correlation with the severity of acidosis rather than increased bilirubin concentration. In mouse neonatal neurons, bilirubin exhibits limited toxicity but robustly potentiates the activity of acid-sensing ion channels (ASICs), resulting in increases in intracellular Ca2+ concentration, spike firings, and cell death. Furthermore, neonatal conditioning with concurrent hyperbilirubinemia and hypoxia-induced acidosis promoted long-term impairments in learning and memory and complex sensorimotor functions in vivo, which are largely attenuated in ASIC1a null mice. These findings suggest that targeting acidosis and ASICs may attenuate neonatal hyperbilirubinemia complications.
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Affiliation(s)
- Ke Lai
- Department of Otorhinolaryngology, Sixth People’s Hospital of Shanghai and Shanghai Jiao Tong University, Shanghai 200032, China
| | - Xing-Lei Song
- Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Hao-Song Shi
- Department of Otorhinolaryngology, Sixth People’s Hospital of Shanghai and Shanghai Jiao Tong University, Shanghai 200032, China
| | - Xin Qi
- Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Chun-Yan Li
- Department of Otorhinolaryngology, Sixth People’s Hospital of Shanghai and Shanghai Jiao Tong University, Shanghai 200032, China
| | - Jia Fang
- Department of Otorhinolaryngology, Sixth People’s Hospital of Shanghai and Shanghai Jiao Tong University, Shanghai 200032, China
| | - Fan Wang
- Department of Otorhinolaryngology, Sixth People’s Hospital of Shanghai and Shanghai Jiao Tong University, Shanghai 200032, China
| | | | - Oleg Krishtal
- Bogomoletz Institute of Physiology of NAS Ukraine, Kyiv 01024, Ukraine
| | - Tian-Le Xu
- Department of Anatomy and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Xiao-Yan Li
- Department of Otorhinolaryngology, Shanghai Children Hospital and Shanghai Jiao Tong University, Shanghai 200062, China
| | - Kun Ni
- Department of Otorhinolaryngology, Shanghai Children Hospital and Shanghai Jiao Tong University, Shanghai 200062, China
| | - Wan-Peng Li
- Department of Otorhinolaryngology, Shanghai Children Hospital and Shanghai Jiao Tong University, Shanghai 200062, China
| | - Hai-Bo Shi
- Department of Otorhinolaryngology, Sixth People’s Hospital of Shanghai and Shanghai Jiao Tong University, Shanghai 200032, China
| | - Lu-Yang Wang
- Program in Neuroscience and Mental Health, SickKids Research Institute, Toronto M5G 1X8, Canada
- Department of Physiology, University of Toronto, Toronto M5S 1A1, Canada
| | - Shan-Kai Yin
- Department of Otorhinolaryngology, Sixth People’s Hospital of Shanghai and Shanghai Jiao Tong University, Shanghai 200032, China
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Lin JH, Hung CH, Han DS, Chen ST, Lee CH, Sun WZ, Chen CC. Sensing acidosis: nociception or sngception? J Biomed Sci 2018; 25:85. [PMID: 30486810 PMCID: PMC6263053 DOI: 10.1186/s12929-018-0486-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 11/09/2018] [Indexed: 12/19/2022] Open
Abstract
Background Sensing tissue acidosis is an important function of the somatosensory nervous system to response to noxious stimuli. Main body In the pain clinic, acid or soreness sensation is a characteristic sensory phenotype of various acute and chronic pain syndromes, such as delayed onset muscle soreness, fibromyalgia, and radicular pain. However, soreness sensation is a sign of successful analgesia for acupuncture and noxipoint therapy. Thus, the nature of acid or soreness sensation is not always nociceptive (or painful) and could be anti-nociceptive. To facilitate the investigation of the molecular and neurobiological mechanisms of soreness sensation, we propose a concept called “sngception (sng- ception)” to describe the response of the somatosensory nervous system to sense tissue acidosis and to distinguish it from nociception. “Sng” is a Taiwanese word that represents the state of soreness while at the same time imitates the natural vocalization of humans feeling sore. Conclusion Here we propose sngception as a specific somatosensory function that transmits the acid sensation from the peripheral to the central nervous system. Sngception could partially overlap with nociception, but it could also transmit antinociception, proprioception, and pruriception.
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Affiliation(s)
- Jiann-Her Lin
- Institute of Biomedical Sciences, Academia Sinica, 128 Academia Rd. Sec. 2, Taipei, 115, Taiwan.,Department of Neurosurgery, Taipei Medical University Hospital, Taipei, Taiwan
| | - Chih-Hsien Hung
- Institute of Biomedical Sciences, Academia Sinica, 128 Academia Rd. Sec. 2, Taipei, 115, Taiwan.,Department of Neurology, Kaohsiung Medical University Hospital; Kaohsiung Medical University, Kaohsiung, Taiwan.,PhD program in Translational Medicine, Kaohsiung Medical University and Academia Sinica, Taipei, Taiwan
| | - Der-Sheng Han
- Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, Bei-Hu Branch, Taipei, Taiwan
| | - Shih-Ting Chen
- Institute of Biomedical Sciences, Academia Sinica, 128 Academia Rd. Sec. 2, Taipei, 115, Taiwan
| | - Cheng-Han Lee
- Institute of Biomedical Sciences, Academia Sinica, 128 Academia Rd. Sec. 2, Taipei, 115, Taiwan
| | - Wei-Zen Sun
- Department of Anesthesiology, National Taiwan University Hospital, Taipei, Taiwan.
| | - Chih-Cheng Chen
- Institute of Biomedical Sciences, Academia Sinica, 128 Academia Rd. Sec. 2, Taipei, 115, Taiwan. .,PhD program in Translational Medicine, Kaohsiung Medical University and Academia Sinica, Taipei, Taiwan. .,Taiwan Mouse Clinic - National Comprehensive Mouse Phenotyping and Drug Testing Center, Academia Sinica, Taipei, Taiwan.
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5
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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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Osmakov DI, Koshelev SG, Andreev YA, Dubinnyi MA, Kublitski VS, Efremov RG, Sobolevsky AI, Kozlov SA. Proton-independent activation of acid-sensing ion channel 3 by an alkaloid, lindoldhamine, from Laurus nobilis. Br J Pharmacol 2018; 175:924-937. [PMID: 29277899 DOI: 10.1111/bph.14134] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 12/05/2017] [Accepted: 12/07/2017] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND AND PURPOSE Acid-sensing ion channels (ASICs) play an important role in synaptic plasticity and learning, as well as in nociception and mechanosensation. ASICs are involved in pain and in neurological and psychiatric diseases, but their therapeutic potential is limited by the lack of ligands activating them at physiological pH. EXPERIMENTAL APPROACH We extracted, purified and determined the structure of a bisbenzylisoquinoline alkaloid, lindoldhamine, (LIN) from laurel leaves. Its effect on ASIC3 channels were characterized, using two-electrode voltage-clamp electrophysiological recordings from Xenopus laevis oocytes. KEY RESULTS At pH 7.4 or higher, LIN activated a sustained, proton-independent, current through rat and human ASIC3 channels, but not rat ASIC1a or ASIC2a channels. LIN also potentiated proton-induced transient currents and promoted recovery from desensitization in human, but not rat, ASIC3 channels. CONCLUSIONS AND IMPLICATIONS We describe a novel ASIC subtype-specific agonist LIN, which induced proton-independent activation of human and rat ASIC3 channels at physiological pH. LIN also acts as a positive allosteric modulator of human, but not rat, ASIC3 channels. This unique, species-selective, ligand of ASIC3, opens new avenues in studies of ASIC structure and function, as well as providing new approaches to drug design.
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Affiliation(s)
- Dmitry I Osmakov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.,Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia
| | - Sergey G Koshelev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Yaroslav A Andreev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.,Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia
| | - Maxim A Dubinnyi
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Vadim S Kublitski
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Roman G Efremov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Alexander I Sobolevsky
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Sergey A Kozlov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
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Targeting ASIC3 for Relieving Mice Fibromyalgia Pain: Roles of Electroacupuncture, Opioid, and Adenosine. Sci Rep 2017; 7:46663. [PMID: 28440280 PMCID: PMC5404229 DOI: 10.1038/srep46663] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 03/21/2017] [Indexed: 01/19/2023] Open
Abstract
Many scientists are seeking better therapies for treating fibromyalgia (FM) pain. We used a mouse model of FM to determine if ASIC3 and its relevant signaling pathway participated in FM pain. We demonstrated that FM-induced mechanical hyperalgesia was attenuated by electroacupuncture (EA). The decrease in fatigue-induced lower motor function in FM mice was also reversed by EA. These EA-based effects were abolished by the opioid receptor antagonist naloxone and the adenosine A1 receptor antagonist rolofylline. Administration of opioid receptor agonist endomorphin (EM) or adenosine A1 receptor agonist N6-cyclopentyladenosine (CPA) has similar results to EA. Similar results were also observed in ASIC3−/− or ASIC3 antagonist (APETx2) injected mice. Using western blotting, we determined that pPKA, pPI3K, and pERK were increased during a dual acidic injection priming period. Nociceptive receptors, such as ASIC3, Nav1.7, and Nav1.8, were upregulated in the dorsal root ganglion (DRG) and spinal cord (SC) of FM mice. Furthermore, pPKA, pPI3K, and pERK were increased in the central thalamus. These aforementioned mechanisms were completely abolished in ASIC3 knockout mice. Electrophysiological results also indicated that acid potentiated Nav currents through ASIC3 and ERK pathway. Our results highlight the crucial role of ASIC3-mediated mechanisms in the treatment of FM-induced mechanical hyperalgesia.
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da Silva Serra I, Husson Z, Bartlett JD, Smith ESJ. Characterization of cutaneous and articular sensory neurons. Mol Pain 2016; 12:1744806916636387. [PMID: 27030722 PMCID: PMC4956179 DOI: 10.1177/1744806916636387] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 02/02/2016] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND A wide range of stimuli can activate sensory neurons and neurons innervating specific tissues often have distinct properties. Here, we used retrograde tracing to identify sensory neurons innervating the hind paw skin (cutaneous) and ankle/knee joints (articular), and combined immunohistochemistry and electrophysiology analysis to determine the neurochemical phenotype of cutaneous and articular neurons, as well as their electrical and chemical excitability. RESULTS Immunohistochemistry analysis using RetroBeads as a retrograde tracer confirmed previous data that cutaneous and articular neurons are a mixture of myelinated and unmyelinated neurons, and the majority of both populations are peptidergic. In whole-cell patch-clamp recordings from cultured dorsal root ganglion neurons, voltage-gated inward currents and action potential parameters were largely similar between articular and cutaneous neurons, although cutaneous neuron action potentials had a longer half-peak duration (HPD). An assessment of chemical sensitivity showed that all neurons responded to a pH 5.0 solution, but that acid-sensing ion channel (ASIC) currents, determined by inhibition with the nonselective acid-sensing ion channel antagonist benzamil, were of a greater magnitude in cutaneous compared to articular neurons. Forty to fifty percent of cutaneous and articular neurons responded to capsaicin, cinnamaldehyde, and menthol, indicating similar expression levels of transient receptor potential vanilloid 1 (TRPV1), transient receptor potential ankyrin 1 (TRPA1), and transient receptor potential melastatin 8 (TRPM8), respectively. By contrast, significantly more articular neurons responded to ATP than cutaneous neurons. CONCLUSION This work makes a detailed characterization of cutaneous and articular sensory neurons and highlights the importance of making recordings from identified neuronal populations: sensory neurons innervating different tissues have subtly different properties, possibly reflecting different functions.
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Affiliation(s)
- Ines da Silva Serra
- Department of Pharmacology, University of Cambridge, Cambridge, UK School of Psychology and Clinical Language Sciences, University of Reading, Reading, UK
| | - Zoé Husson
- Department of Pharmacology, University of Cambridge, Cambridge, UK
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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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Lin YW, Chen CC. Electrophysiological characteristics of IB4-negative TRPV1-expressing muscle afferent DRG neurons. Biophysics (Nagoya-shi) 2015; 11:9-16. [PMID: 27493509 PMCID: PMC4736793 DOI: 10.2142/biophysics.11.9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 12/26/2014] [Indexed: 01/23/2023] Open
Abstract
Muscle afferent neurons that express transient receptor potential vanilloid type I (TRPV1) are responsible for muscle pain associated with tissue acidosis. We have previously found that TRPV1 of isolectin B4 (IB4)-negative muscle nociceptors plays an important role in the acid-induced hyperalgesic priming and the development of chronic hyperalgesia in a mouse model of fibromyalgia. To understand the electrophysiological properties of the TRPV1-expressing muscle afferent neurons, we used whole-cell patch clamp recording to study the acid responsiveness and action potential (AP) configuration of capsaicin-sensitive neurons innervating to gastrocnemius muscle. Here we showed that IB4-negative TRPV1-expressing muscle afferent neurons are heterogeneous in terms of cell size, resting membrane potential, AP configuration, tetrodotoxin (TTX)-resistance, and acid-induced current (Iacid), as well as capsaicin-induced current (Icap). TRPV1-expressing neurons were all acid-sensitive and could be divided into two acid-sensitive groups depending on an acid-induced sustained current (type I) or an acid-induced biphasic ASIC3-like current (type II). Type I TRPV1-expressing neurons were distinguishable from type II TRPV1-expressing neurons in AP overshoot, after-hyperpolarization duration, and all Iacid parameters, but not in AP threshold, TTX-resistance, resting membrane potential, and Icap parameters. These differential biophysical properties of TRPV1-expressing neurons might partially annotate their different roles involved in the development and maintenance of chronic muscle pain.
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Affiliation(s)
- Yi-Wen Lin
- College of Chinese Medicine, Graduate Institute of Acupuncture Science, China Medical University, Taichung 40402, Taiwan; Research Center for Chinese Medicine & Acupuncture, China Medical University, Taichung 40402, Taiwan
| | - Chih-Cheng Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan; Taiwan Mouse Clinic, Academia Sinica, Taipei 115, Taiwan
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11
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Gründer S, Pusch M. Biophysical properties of acid-sensing ion channels (ASICs). Neuropharmacology 2015; 94:9-18. [PMID: 25585135 DOI: 10.1016/j.neuropharm.2014.12.016] [Citation(s) in RCA: 144] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 12/01/2014] [Accepted: 12/04/2014] [Indexed: 01/23/2023]
Abstract
Acid-sensing ion channels (ASICs) are ligand-gated ion channels that are exquisitely sensitive to extracellular protons and can sense transient as well as sustained acidification. In this review, we will discuss activation and desensitization of ASICs by protons. We show that a linear reaction scheme can reproduce the basic electrophysiological properties of ASICs, including steady-state desensitization. Moreover, we will discuss how a desensitizing receptor can sense sustained acidosis and what we know about the putative proton sensor. We will briefly discuss modulation of proton gating by neuropeptides and small positively charged ligands. Finally, we will review the pore properties of ASICs and their relation to the recently reported crystal structure of the open ASIC pore. This article is part of the Special Issue entitled 'Acid-Sensing Ion Channels in the Nervous System'.
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Affiliation(s)
- Stefan Gründer
- Institute of Physiology, RWTH Aachen University, Pauwelsstrasse 30, D-52074 Aachen, Germany.
| | - Michael Pusch
- Institute of Biophysics, National Research Council, Via De Marini 6, Genoa, Italy
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12
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Lin SH, Sun WH, Chen CC. Genetic exploration of the role of acid-sensing ion channels. Neuropharmacology 2015; 94:99-118. [PMID: 25582292 DOI: 10.1016/j.neuropharm.2014.12.011] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 12/03/2014] [Accepted: 12/04/2014] [Indexed: 12/27/2022]
Abstract
Advanced gene targeting technology and related tools in mice have been incorporated into studies of acid-sensing ion channels (ASICs). A single ASIC subtype can be knocked out specifically and screened thoroughly for expression in the nervous system at the cellular level. Mapping studies have further shed light on the initiation and identification of related behavioral phenotypes. Here we review studies involving genetically engineered mouse models used to investigate the physiological function of individual ASIC subtypes: ASIC1 (and ASIC1a), ASIC2, ASIC3 and ASIC4. We discuss the detailed expression studies and significant phenotypes revealed with gene knockout for most known Asic subtypes. Each strategy designed to manipulate mouse genetics has advantages and disadvantages. We discuss the limitations of these Asic-knockout models and propose future directions to solve the genetic issues. This article is part of the Special Issue entitled 'Acid-Sensing Ion Channels in the Nervous System'.
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Affiliation(s)
- Shing-Hong Lin
- Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan.
| | - Wei-Hsin Sun
- Department of Life Sciences, National Central University, Jhongli 32054, Taiwan.
| | - Chih-Cheng Chen
- Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; 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.
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13
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Characteristics of dorsal root ganglia neurons sensitive to Substance P. Mol Pain 2014; 10:73. [PMID: 25431155 PMCID: PMC4280706 DOI: 10.1186/1744-8069-10-73] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Accepted: 10/20/2014] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Substance P modulates ion channels and the excitability of sensory neurons in pain pathways. Within the heterogeneous population of Dorsal Root Ganglia (DRG) primary sensory neurons, the properties of cells that are sensitive to Substance P are poorly characterized. To define this population better, dissociated rat DRG neurons were tested for their responsiveness to capsaicin, ATP and acid. Responses to ATP were classified according to the kinetics of current activation and desensitization. The same cells were then tested for modulation of action potential firing by Substance P. RESULTS Acid and capsaicin currents were more frequently encountered in the largest diameter neurons. P2X3-like ATP currents were concentrated in small diameter neurons. Substance P modulated the excitability in 20 of 72 cells tested (28%). Of the Substance P sensitive cells, 10 exhibited an increase in excitability and 10 exhibited a decrease in excitability. There was no significant correlation between sensitivity to capsaicin and to Substance P. Excitatory effects of Substance P were strongly associated with cells that had large diameters, fired APs with large overshoots and slowly decaying after hyperpolarizations, and expressed acid currents at pH 7. No neurons that were excited by Substance P presented P2X3-like currents. In contrast, neurons that exhibited inhibitory effects of Substance P fired action potentials with rapidly decaying after hyperpolarizations. CONCLUSION We conclude that excitatory effects of Substance P are restricted to a specific neuronal subpopulation with limited expression of putative nociceptive markers.
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Chen WN, Lee CH, Lin SH, Wong CW, Sun WH, Wood JN, Chen CC. Roles of ASIC3, TRPV1, and NaV1.8 in the transition from acute to chronic pain in a mouse model of fibromyalgia. Mol Pain 2014; 10:40. [PMID: 24957987 PMCID: PMC4083869 DOI: 10.1186/1744-8069-10-40] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 06/18/2014] [Indexed: 01/23/2023] Open
Abstract
Background Tissue acidosis is effective in causing chronic muscle pain. However, how muscle nociceptors contribute to the transition from acute to chronic pain is largely unknown. Results Here we showed that a single intramuscular acid injection induced a priming effect on muscle nociceptors of mice. The primed muscle nociceptors were plastic and permitted the development of long-lasting chronic hyperalgesia induced by a second acid insult. The plastic changes of muscle nociceptors were modality-specific and required the activation of acid-sensing ion channel 3 (ASIC3) or transient receptor potential cation channel V1 (TRPV1). Activation of ASIC3 was associated with increased activity of tetrodotoxin (TTX)-sensitive voltage-gated sodium channels but not protein kinase Cϵ (PKCϵ) in isolectin B4 (IB4)-negative muscle nociceptors. In contrast, increased activity of TTX-resistant voltage-gated sodium channels with ASIC3 or TRPV1 activation in NaV1.8-positive muscle nociceptors was required for the development of chronic hyperalgesia. Accordingly, compared to wild type mice, NaV1.8-null mice showed briefer acid-induced hyperalgesia (5 days vs. >27 days). Conclusion ASIC3 activation may manifest a new type of nociceptor priming in IB4-negative muscle nociceptors. The activation of ASIC3 and TRPV1 as well as enhanced NaV1.8 activity are essential for the development of long-lasting hyperalgesia in acid-induced, chronic, widespread muscle pain.
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Affiliation(s)
| | | | | | | | | | | | - Chih-Cheng Chen
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan.
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Abnormal cardiac autonomic regulation in mice lacking ASIC3. BIOMED RESEARCH INTERNATIONAL 2014; 2014:709159. [PMID: 24804235 PMCID: PMC3996306 DOI: 10.1155/2014/709159] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/26/2013] [Accepted: 02/25/2014] [Indexed: 12/11/2022]
Abstract
Integration of sympathetic and parasympathetic outflow is essential in maintaining normal cardiac autonomic function. Recent studies demonstrate that acid-sensing ion channel 3 (ASIC3) is a sensitive acid sensor for cardiac ischemia and prolonged mild acidification can open ASIC3 and evoke a sustained inward current that fires action potentials in cardiac sensory neurons. However, the physiological role of ASIC3 in cardiac autonomic regulation is not known. In this study, we elucidate the role of ASIC3 in cardiac autonomic function using Asic3−/− mice. Asic3−/− mice showed normal baseline heart rate and lower blood pressure as compared with their wild-type littermates. Heart rate variability analyses revealed imbalanced autonomic regulation, with decreased sympathetic function. Furthermore, Asic3−/− mice demonstrated a blunted response to isoproterenol-induced cardiac tachycardia and prolonged duration to recover to baseline heart rate. Moreover, quantitative RT-PCR analysis of gene expression in sensory ganglia and heart revealed that no gene compensation for muscarinic acetylcholines receptors and beta-adrenalin receptors were found in Asic3−/− mice. In summary, we unraveled an important role of ASIC3 in regulating cardiac autonomic function, whereby loss of ASIC3 alters the normal physiological response to ischemic stimuli, which reveals new implications for therapy in autonomic nervous system-related cardiovascular diseases.
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Chu XP, Grasing KA, Wang JQ. Acid-sensing ion channels contribute to neurotoxicity. Transl Stroke Res 2013; 5:69-78. [PMID: 24323724 DOI: 10.1007/s12975-013-0305-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2013] [Revised: 10/06/2013] [Accepted: 11/04/2013] [Indexed: 12/13/2022]
Abstract
Acidosis that occurs under pathological conditions not only affects intracellular signaling molecules, but also directly activates a unique family of ligand-gated ion channels: acid-sensing ion channels (ASICs). ASICs are widely expressed throughout the central and peripheral nervous systems and play roles in pain sensation, learning and memory, and fear conditioning. Overactivation of ASICs contributes to neurodegenerative diseases such as ischemic brain/spinal cord injury, multiple sclerosis, Parkinson's disease, and Huntington's disease. Thus, targeting ASICs might be a potential therapeutic strategy for these conditions. This mini-review focuses on the electrophysiology and pharmacology of ASICs and roles of ASICs in neuronal toxicity.
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Affiliation(s)
- Xiang-Ping Chu
- Departments of Basic Medical Science and Anesthesiology, School of Medicine, University of Missouri-Kansas City, 2411 Holmes Street, Room M3-417, Kansas City, MO, 64108-2792, USA,
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Wu MT, Huang PY, Yen CT, Chen CC, Lee MJ. A novel SCN9A mutation responsible for primary erythromelalgia and is resistant to the treatment of sodium channel blockers. PLoS One 2013; 8:e55212. [PMID: 23383113 PMCID: PMC3561374 DOI: 10.1371/journal.pone.0055212] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 12/19/2012] [Indexed: 01/14/2023] Open
Abstract
Primary erythromelalgia (PE) is an autosomal dominant neurological disorder characterized by severe burning pain and erythema in the extremities upon heat stimuli or exercise. Mutations in human SCN9A gene, encoding the α-subunit of the voltage-gated sodium channel, Na(v)1.7, were found to be responsible for PE. Three missense mutations of SCN9A gene have recently been identified in Taiwanese patients including a familial (I136V) and two sporadic mutations (I848T, V1316A). V1316A is a novel mutation and has not been characterized yet. Topologically, I136V is located in DI/S1 segment and both I848T and V1316A are located in S4-S5 linker region of DII and DIII domains, respectively. To characterize the elelctrophysiological manifestations, the channel conductance with whole-cell patch clamp was recorded on the over-expressed Chinese hamster overy cells. As compared with wild type, the mutant channels showed a significant hyperpolarizing shift in voltage dependent activation and a depolarizing shift in steady-state fast inactivation. The recovery time from channel inactivation is faster in the mutant than in the wild type channels. Since warmth can trigger and exacerbate symptoms, we then examine the influence of tempearture on the sodium channel conduction. At 35°C, I136V and V1316A mutant channels exhibit a further hyperpolarizing shift at activation as compared with wild type channel, even though wild type channel also produced a significant hyperpolarizing shift compared to that of 25°C. High temperature caused a significant depolarizing shift in steady-state fast inactivation in all three mutant channels. These findings may confer to the hyperexcitability of sensory neurons, especially at high temperature. In order to identifying an effective treatment, we tested the IC₅₀ values of selective sodium channel blockers, lidocaine and mexiletine. The IC₅₀ for mexiletine is lower for I848T mutant channel as compared to that of the wild type and other two mutants which is comparable to the clinical observations.
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Affiliation(s)
- Min-Tzu Wu
- Graduate Institute of Zoology, College of Life Sciences, National Taiwan University, Taipei, Taiwan
| | - Po-Yuan Huang
- Graduate Institute of Zoology, College of Life Sciences, National Taiwan University, Taipei, Taiwan
| | - Chen-Tung Yen
- Graduate Institute of Zoology, College of Life Sciences, National Taiwan University, Taipei, Taiwan
| | - Chih-Cheng Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Ming-Jen Lee
- Department of Neurology, National Taiwan University Hospital, Tapei, Taiwan
- Medical Genetics, National Taiwan University Hospital, Tapei, Taiwan
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18
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He QL, Chen Y, Qin J, Mo SL, Wei M, Zhang JJ, Li MN, Zou XN, Zhou SF, Chen XW, Sun LB. Osthole, a herbal compound, alleviates nucleus pulposus-evoked nociceptive responses through the suppression of overexpression of acid-sensing ion channel 3 (ASIC3) in rat dorsal root ganglion. Med Sci Monit 2012; 18:BR229-36. [PMID: 22648244 PMCID: PMC3560735 DOI: 10.12659/msm.882899] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Osthole (Ost), a natural coumarin derivative, has been shown to inhibit many pro-inflammatory mediators and block voltage-gated Na+ channels. During inflammation, acidosis is an important pain inducer which activates nociceptors by gating depolarizing cationic channels, such as acid-sensing ion channel 3 (ASIC3). The aim of this study was to examine the effects of Ost on nucleus pulposus-evoked nociceptive responses and ASIC3 over-expression in the rat dorsal root ganglion, and to investigate the possible mechanism. MATERIAL/METHODS Radicular pain was generated with application of nucleus pulposus (NP) to nerve root. Mechanical allodynia was evaluated using von Frey filaments with logarithmically incremental rigidity to calculate the 50% probability thresholds for mechanical paw withdrawal. ASIC3 protein expression in dorsal root ganglions (DRGs) was assessed with Western blot and immunohistochemistry. Membrane potential (MP) shift of DRG neurons induced by ASIC3-sensitive acid (pH6.5) was determined by DiBAC(4) (3) fluorescence intensity (F.I.). RESULTS The NP-evoked mechanical hyperalgesia model showed allodynia for 3 weeks, and ASIC3 expression was up-regulated in DRG neurons, reaching peak on Day 7. Epidural administration of Ost induced a remarkable and prolonged antinociceptive effect, accompanied by an inhibition of over-expressed ASIC3 protein and of abnormal shift of MP. Amiloride (Ami), an antagonist of ASIC3, strengthened the antinociceptive effect of Ost. CONCLUSIONS Up-regulation of ASIC3 expression may be associated with NP-evoked mechanical hyperalgesia. A single epidural injection of Ost decreased ASIC3 expression in DGR neurons and the pain in the NP-evoked mechanical hyperalgesia model. Osthole may be of great benefit for preventing chronic pain status often seen in lumbar disc herniation (LDH).
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Affiliation(s)
- Qiu-Lan He
- Department of Anesthesiology, First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
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Wu WL, Cheng CF, Sun WH, Wong CW, Chen CC. Targeting ASIC3 for pain, anxiety, and insulin resistance. Pharmacol Ther 2011; 134:127-38. [PMID: 22233754 DOI: 10.1016/j.pharmthera.2011.12.009] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Accepted: 12/05/2011] [Indexed: 02/07/2023]
Abstract
The acid-sensing ion channel 3 (ASIC3) is a pH sensor that responds to mild extracellular acidification and is predominantly expressed in nociceptors. There is much interest in targeting ASIC3 to relieve pain associated with tissue acidosis, and selective drugs targeting ASIC3 have been used to relieve acid-evoked pain in animal models and human studies. There is accumulating evidence that ASIC3 is widely expressed in many neuronal and non-neuronal cells, such as neurons in the brain and adipose cells, albeit to a lesser extent than in nociceptors. Asic3-knockout mice have reduced anxiety levels and enhanced insulin sensitivity, suggesting that antagonizing ASIC3 has additional benefits. This view is tempered by recent studies suggesting that Asic3-knockout mice may experience cardiovascular disturbances. Due to the development of ASIC3 antagonists as analgesics, we review here the additional benefits, safety, risks, and strategy associated with antagonizing ASIC3 function.
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Affiliation(s)
- Wei-Li Wu
- Institute of Biomedical Sciences, Academia Sinica, 128 Academia Road, Section 2, Taipei 115, Taiwan
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20
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An antinociceptive role for substance P in acid-induced chronic muscle pain. Proc Natl Acad Sci U S A 2011; 109:E76-83. [PMID: 22084095 DOI: 10.1073/pnas.1108903108] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Release of substance P (SP) from nociceptive nerve fibers and activation of its receptor neurokinin 1 (NK1) are important effectors in the transmission of pain signals. Nonetheless, the role of SP in muscle pain remains unknown. Here we show that a single i.m. acid injection in mice lacking SP signaling by deletion of the tachykinin precursor 1 (Tac1) gene or coadministration of NK1 receptor antagonists produces long-lasting hyperalgesia rather than the transient hyperalgesia seen in control animals. The inhibitory effect of SP was found exclusively in neurons expressing acid-sensing ion channel 3, where SP enhances M-channel-like potassium currents through the NK1 receptor in a G protein-independent but tyrosine kinase-dependent manner. Furthermore, the SP signaling could alter action potential thresholds and modulate the expression of TTX-resistant sodium currents in medium-sized muscle nociceptors. Thus, i.m. SP mediates an unconventional NK1 receptor signal pathway to inhibit acid activation in muscle nociceptors, resulting in an unexpected antinociceptive effect against chronic mechanical hyperalgesia, here induced by repeated i.m. acid injection.
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21
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Chen WH, Hsieh CL, Huang CP, Lin TJ, Tzen JT, Ho TY, Lin YW. Acid-sensing ion channel 3 mediates peripheral anti-hyperalgesia effects of acupuncture in mice inflammatory pain. J Biomed Sci 2011; 18:82. [PMID: 22070775 PMCID: PMC3233511 DOI: 10.1186/1423-0127-18-82] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Accepted: 11/09/2011] [Indexed: 12/11/2022] Open
Abstract
Background Peripheral tissue inflammation initiates hyperalgesia accompanied by tissue acidosis, nociceptor activation, and inflammation mediators. Recent studies have suggested a significantly increased expression of acid-sensing ion channel 3 (ASIC3) in both carrageenan- and complete Freund's adjuvant (CFA)-induced inflammation. This study tested the hypothesis that acupuncture is curative for mechanical hyperalgesia induced by peripheral inflammation. Methods Here we used mechanical stimuli to assess behavioral responses in paw and muscle inflammation induced by carrageenan or CFA. We also used immunohistochemistry staining and western blot methodology to evaluate the expression of ASIC3 in dorsal root ganglion (DRG) neurons. Results In comparison with the control, the inflammation group showed significant mechanical hyperalgesia with both intraplantar carrageenan and CFA-induced inflammation. Interestingly, both carrageenan- and CFA-induced hyperalgesia were accompanied by ASIC3 up-regulation in DRG neurons. Furthermore, electroacupuncture (EA) at the ST36 rescued mechanical hyperalgesia through down-regulation of ASIC3 overexpression in both carrageenan- and CFA-induced inflammation. Conclusions In addition, electrical stimulation at the ST36 acupoint can relieve mechanical hyperalgesia by attenuating ASIC3 overexpression.
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Affiliation(s)
- Wei-Hsin Chen
- College of Agriculture and Natural Resources, Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
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22
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Localized bimodal response of neurite extensions and structural proteins in dorsal-root ganglion neurons with controlled polydimethylsiloxane substrate stiffness. J Biomech 2011; 44:856-62. [DOI: 10.1016/j.jbiomech.2010.12.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Revised: 12/08/2010] [Accepted: 12/08/2010] [Indexed: 12/17/2022]
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23
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Li WG, Xu TL. ASIC3 channels in multimodal sensory perception. ACS Chem Neurosci 2011; 2:26-37. [PMID: 22778854 DOI: 10.1021/cn100094b] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Accepted: 11/05/2010] [Indexed: 02/06/2023] Open
Abstract
Acid-sensing ion channels (ASICs), which are members of the sodium-selective cation channels belonging to the epithelial sodium channel/degenerin (ENaC/DEG) family, act as membrane-bound receptors for extracellular protons as well as nonproton ligands. At least five ASIC subunits have been identified in mammalian neurons, which form both homotrimeric and heterotrimeric channels. The highly proton sensitive ASIC3 channels are predominantly distributed in peripheral sensory neurons, correlating with their roles in multimodal sensory perception, including nociception, mechanosensation, and chemosensation. Different from other ASIC subunit composing ion channels, ASIC3 channels can mediate a sustained window current in response to mild extracellular acidosis (pH 7.3-6.7), which often occurs accompanied by many sensory stimuli. Furthermore, recent evidence indicates that the sustained component of ASIC3 currents can be enhanced by nonproton ligands including the endogenous metabolite agmatine. In this review, we first summarize the growing body of evidence for the involvement of ASIC3 channels in multimodal sensory perception and then discuss the potential mechanisms underlying ASIC3 activation and mediation of sensory perception, with a special emphasis on its role in nociception. We conclude that ASIC3 activation and modulation by diverse sensory stimuli represent a new avenue for understanding the role of ASIC3 channels in sensory perception. Furthermore, the emerging implications of ASIC3 channels in multiple sensory dysfunctions including nociception allow the development of new pharmacotherapy.
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Affiliation(s)
- Wei-Guang Li
- Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Tian-Le Xu
- Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
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Cheng CF, Chen IL, Cheng MH, Lian WS, Lin CC, Kuo TB, Chen CC. Acid-Sensing Ion Channel 3, But Not Capsaicin Receptor TRPV1, Plays a Protective Role in Isoproterenol-Induced Myocardial Ischemia in Mice. Circ J 2011; 75:174-8. [DOI: 10.1253/circj.cj-10-0490] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ching-Feng Cheng
- Institute of Biomedical Sciences, Academia Sinica
- Department of Medical Research, Tzu Chi General Hospital and Department of Pediatrics, Tzu Chi University
| | - I-Lun Chen
- Institute of Biomedical Sciences, Academia Sinica
- Institute of Zoology, National Taiwan University
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25
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Affiliation(s)
- Cheng-Han Lee
- Institute of Neuroscience, National Yang-Ming University
- Institute of Biomedical Sciences, Academia Sinica
| | - Synthia H. Sun
- Institute of Neuroscience, National Yang-Ming University
| | - Shing-Hong Lin
- Institute of Biomedical Sciences, Academia Sinica
- Graduate Institute of Life Sciences, National Defense Medical Center
| | - Chih-Cheng Chen
- Institute of Neuroscience, National Yang-Ming University
- Institute of Biomedical Sciences, Academia Sinica
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26
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Anangi R, Chen CC, Lin YW, Cheng YR, Cheng CH, Chen YC, Chu YP, Chuang WJ. Expression in Pichia pastoris and characterization of APETx2, a specific inhibitor of acid sensing ion channel 3. Toxicon 2010; 56:1388-97. [DOI: 10.1016/j.toxicon.2010.08.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 08/09/2010] [Accepted: 08/11/2010] [Indexed: 10/19/2022]
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Jiang Q, Papasian CJ, Wang JQ, Xiong ZG, Chu XP. Inhibitory regulation of acid-sensing ion channel 3 by zinc. Neuroscience 2010; 169:574-83. [PMID: 20580786 DOI: 10.1016/j.neuroscience.2010.05.043] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Revised: 05/14/2010] [Accepted: 05/18/2010] [Indexed: 02/03/2023]
Abstract
Acid-sensing ion channel 3 (ASIC3) is a proton-gated, voltage-insensitive Na(+) channel that is expressed primarily in peripheral sensory neurons and plays an important role in pain perception, particularly as a pH sensor following cardiac ischemia. We previously reported that ASIC3 currents are not affected by zinc at nanomolar concentrations. In this study, we examined the potential role of micromolar zinc in the regulation of ASIC3. In CHO cells expressing ASIC3, we found that ASIC3 currents triggered by dropping the pH from 7.4 to 6.0 were inhibited by pretreatment with zinc in a concentration-dependent manner; the half-maximum inhibitory concentration of zinc was 61 muM. ASIC currents activated by a relatively small drop in pH from 7.4 to 7.2 or 7.0 were also subject to inhibition by zinc. The inhibition was fast and pH independent, and occurred within a relatively narrow range of zinc concentrations between 30 and 300 muM. Further, increasing extracellular Ca(2+) concentrations from 2 to 10 mM failed to affect inhibition of ASIC3 currents by zinc. Experimentally elevating intracellular zinc levels did not affect the inhibition of ASIC3 currents by equal concentrations of extracellular zinc, and modification of cysteine or histidine residues had no effect on the inhibition of ASIC3 currents by zinc. These collective results suggest that zinc is an important regulator of ASIC3 at physiological concentrations, that zinc inhibits ASIC3 in a pH- and Ca(2+)-independent manner, and that inhibition of ASIC3 currents is dependent upon the interaction of zinc with extracellular domain(s) of ASIC3.
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Affiliation(s)
- Q Jiang
- Department of Basic Medical Science, School of Medicine, University of Missouri-Kansas City, 2411 Holmes Street, Kansas City, MO 64108, USA
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28
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Wu WL, Lin YW, Min MY, Chen CC. Mice lacking Asic3 show reduced anxiety-like behavior on the elevated plus maze and reduced aggression. GENES BRAIN AND BEHAVIOR 2010; 9:603-14. [PMID: 20497234 DOI: 10.1111/j.1601-183x.2010.00591.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Sensing external stimulation is crucial for central processing in the brain and subsequent behavioral expression. Although sensory alteration or deprivation may result in behavioral changes, most studies related to the control of behavior have focused on central mechanisms. Here we created a sensory deficit model of mice lacking acid-sensing ion channel 3 (Asic3(-/-)) to probe behavioral alterations. ASIC3 is predominately distributed in the peripheral nervous system. RT-PCR and immunohistochemistry used to examine the expression of Asic3 in the mouse brain showed near-background mRNA and protein levels of ASIC3 throughout the whole brain, except for the sensory mesencephalic trigeminal nucleus. Consistent with the expression results, Asic3 knockout had no effect on synaptic plasticity of the hippocampus and the behavioral tasks of motor function, learning and memory. In anxiety behavior tasks, Asic3(-/-) mice spent more time in the open arms of an elevated plus maze than did their wild-type littermates. Asic3(-/-) mice also displayed less aggressiveness toward intruders but more stereotypic repetitive behaviors during resident-intruder testing than did wild-type littermates. Therefore, loss of ASIC3 produced behavioral changes in anxiety and aggression in mice, which suggests that ASIC3-dependent sensory activities might relate to the central process of emotion modulation.
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Affiliation(s)
- W-L Wu
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
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Differential Localization of Acid-Sensing Ion Channels 1 and 2 in Human Cutaneus Pacinian Corpuscles. Cell Mol Neurobiol 2010; 30:841-8. [DOI: 10.1007/s10571-010-9511-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Accepted: 03/01/2010] [Indexed: 12/13/2022]
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Acid-sensing ion channels 3: a potential therapeutic target for pain treatment in arthritis. Mol Biol Rep 2009; 37:3233-8. [PMID: 19885742 DOI: 10.1007/s11033-009-9907-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Accepted: 10/16/2009] [Indexed: 10/20/2022]
Abstract
Acid-sensing ion channels 3 (ASIC3) is the most sensitive to such a pH change, predominantly distributed in the sensory peripheral nervous system, and strongly correlated with pain. Recently, there is increasing evidence that ASIC3 may contribute to the pathogenesis of chronic inflammatory pain diseases due to it is predominantly expressed in dorsal root ganglia (DRG) neurons making it a good candidate for a pain sensor. Elevated expression of ASIC3 was found in DRG of rodents with inflamed hind paws. In addition, it has been shown that ASIC3 gene knock-out mice (ASIC3-/-) exhibited no enhanced hyperalgesia in inflamed joint. All theses findings suggest that ASIC3 have important biological effects in inflammation that might be a promising therapeutic target for arthritis pain. In this review, we will briefly discuss the biological features of ASIC3 and summarize recent advances on the role of ASIC3 in the pathogenesis and treatment of arthritis pain.
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Is thermal nociception only sensed by the capsaicin receptor, TRPV1? Anat Sci Int 2009; 84:122-8. [PMID: 19562439 DOI: 10.1007/s12565-009-0048-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2008] [Accepted: 05/14/2009] [Indexed: 02/03/2023]
Abstract
Mammalian heat pain perception is well documented as a molecular event in the primary afferent neurons expressing TRPV1. Six types of thermo-TRPs were found, i.e., TRPV1-4, TRPM8 and TRPA1. The former TRPV1, 2 and TRPV3, 4 are sensitive to noxious heat and warmth, and the latter two are sensitive to cool or cold, respectively. We attempted to provide a hypothesis to explain the paradox in which TRPV1 knockout mice and capsaicin-pretreated mice with severe loss of small dorsal root ganglion (DRG) neurons behave normally to noxious heat. From the general view that TRPV1 is preferentially expressed in C-fibers responding to a moderate thermal threshold (>43 degrees C) and TRPV2 in Adelta-fibers to high threshold temperatures (>52 degrees C), the above phenomenon is perplexing. Woodbury et al. (J Neurosci 24:6410-6415, 2004) offered two pain transduction mechanisms, one being TRPV1/2-independent and the other TRPV1-dependent. The former detects noxious heat under normal conditions without the presence of TRPV1 or TRPV2, and the latter requires TRPV1 under pathophysiological conditions. Unidentified isolectin B4 (IB4)-positive but TRPV1-negative small neurons with a higher noxious heat threshold are feasible, because a spliced isoform of TRPV1 responsive to noxious heat (47 degrees C) but not responsive to either proton or capsaicin is present in human and rat sensory neurons. Thus, the IB4-positive but TRPV1-negative small sensory neurons must have a crucial role in the noxious heat response.
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Calcium-permeable acid-sensing ion channel in nociceptive plasticity: A new target for pain control. Prog Neurobiol 2009; 87:171-80. [DOI: 10.1016/j.pneurobio.2009.01.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Lin YW, Cheng CM, Leduc PR, Chen CC. Understanding sensory nerve mechanotransduction through localized elastomeric matrix control. PLoS One 2009; 4:e4293. [PMID: 19173000 PMCID: PMC2627935 DOI: 10.1371/journal.pone.0004293] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Accepted: 12/04/2008] [Indexed: 01/09/2023] Open
Abstract
Background While neural systems are known to respond to chemical and electrical stimulation, the effect of mechanics on these highly sensitive cells is still not well understood. The ability to examine the effects of mechanics on these cells is limited by existing approaches, although their overall response is intimately tied to cell-matrix interactions. Here, we offer a novel method, which we used to investigate stretch-activated mechanotransduction on nerve terminals of sensory neurons through an elastomeric interface. Methodology/Principal Findings To apply mechanical force on neurites, we cultured dorsal root ganglion neurons on an elastic substrate, polydimethylsiloxane (PDMS), coated with extracellular matrices (ECM). We then implemented a controlled indentation scheme using a glass pipette to mechanically stimulate individual neurites that were adjacent to the pipette. We used whole-cell patch clamping to record the stretch-activated action potentials on the soma of the single neurites to determine the mechanotransduction-based response. When we imposed specific mechanical force through the ECM, we noted a significant neuronal action potential response. Furthermore, because the mechanotransduction cascade is known to be directly affected by the cytoskeleton, we investigated the cell structure and its effects. When we disrupted microtubules and actin filaments with nocodozale or cytochalasin-D, respectively, the mechanically induced action potential was abrogated. In contrast, when using blockers of channels such as TRP, ASIC, and stretch-activated channels while mechanically stimulating the cells, we observed almost no change in action potential signalling when compared with mechanical activation of unmodified cells. Conclusions/Significance These results suggest that sensory nerve terminals have a specific mechanosensitive response that is related to cell architecture.
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Affiliation(s)
- Yi-Wen Lin
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
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Yen YT, Tu PH, Chen CJ, Lin YW, Hsieh ST, Chen CC. Role of acid-sensing ion channel 3 in sub-acute-phase inflammation. Mol Pain 2009; 5:1. [PMID: 19126241 PMCID: PMC2632618 DOI: 10.1186/1744-8069-5-1] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2008] [Accepted: 01/07/2009] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Inflammation-mediated hyperalgesia involves tissue acidosis and sensitization of nociceptors. Many studies have reported increased expression of acid-sensing ion channel 3 (ASIC3) in inflammation and enhanced ASIC3 channel activity with pro-inflammatory mediators. However, the role of ASIC3 in inflammation remains inconclusive because of conflicting results generated from studies of ASIC3 knockout (ASIC3-/-) or dominant-negative mutant mice, which have shown normal, decreased or increased hyperalgesia during inflammation. RESULTS Here, we tested whether ASIC3 plays an important role in inflammation of subcutaneous tissue of paw and muscle in ASIC3-/- mice induced by complete Freund's adjuvant (CFA) or carrageenan by investigating behavioral and pathological responses, as well as the expression profile of ion channels. Compared with the ASIC3+/+ controls, ASIC3-/- mice showed normal thermal and mechanical hyperalgesia with acute (4-h) intraplantar CFA- or carrageenan-induced inflammation, but the hyperalgesic effects in the sub-acute phase (1-2 days) were milder in all paradigms except for thermal hyperalgesia with CFA-induced inflammation. Interestingly, carrageenan-induced primary hyperalgesia was accompanied by an ASIC3-dependent Nav1.9 up-regulation and increase of tetrodotoxin (TTX)-resistant sodium currents. CFA-inflamed muscle did not evoke hyperalgesia in ASIC3-/- or ASIC3+/+ mice, whereas carrageenan-induced inflammation in muscle abolished mechanical hyperalgesia in ASIC3-/- mice, as previously described. However, ASIC3-/- mice showed attenuated pathological features such as less CFA-induced granulomas and milder carrageenan-evoked vasculitis as compared with ASIC3+/+ mice. CONCLUSION We provide a novel finding that ASIC3 participates in the maintenance of sub-acute-phase primary hyperalgesia in subcutaneous inflammation and mediates the process of granuloma formation and vasculitis in intramuscular inflammation.
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Affiliation(s)
- Yi-Tin Yen
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan.
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ASIC3, a sensor of acidic and primary inflammatory pain. EMBO J 2008; 27:3047-55. [PMID: 18923424 DOI: 10.1038/emboj.2008.213] [Citation(s) in RCA: 316] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2008] [Accepted: 09/17/2008] [Indexed: 12/13/2022] Open
Abstract
Acid-sensing ion channels (ASICs) are cationic channels activated by extracellular acidosis that are expressed in both central and peripheral nervous systems. Although peripheral ASICs seem to be natural sensors of acidic pain (e.g., in inflammation, ischaemia, lesions or tumours), a direct demonstration is still lacking. We show that approximately 60% of rat cutaneous sensory neurons express ASIC3-like currents. Native as well as recombinant ASIC3 respond synergistically to three different inflammatory signals that are slight acidifications (approximately pH 7.0), hypertonicity and arachidonic acid (AA). Moderate pH, alone or in combination with hypertonicity and AA, increases nociceptors excitability and produces pain suppressed by the toxin APETx2, a specific blocker of ASIC3. Both APETx2 and the in vivo knockdown of ASIC3 with a specific siRNA also have potent analgesic effects against primary inflammation-induced hyperalgesia in rat. Peripheral ASIC3 channels are thus essential sensors of acidic pain and integrators of molecular signals produced during inflammation where they contribute to primary hyperalgesia.
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Light AR, Hughen RW, Zhang J, Rainier J, Liu Z, Lee J. Dorsal root ganglion neurons innervating skeletal muscle respond to physiological combinations of protons, ATP, and lactate mediated by ASIC, P2X, and TRPV1. J Neurophysiol 2008; 100:1184-201. [PMID: 18509077 PMCID: PMC6195653 DOI: 10.1152/jn.01344.2007] [Citation(s) in RCA: 221] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2007] [Accepted: 05/27/2008] [Indexed: 12/14/2022] Open
Abstract
The adequate stimuli and molecular receptors for muscle metaboreceptors and nociceptors are still under investigation. We used calcium imaging of cultured primary sensory dorsal root ganglion (DRG) neurons from C57Bl/6 mice to determine candidates for metabolites that could be the adequate stimuli and receptors that could detect these stimuli. Retrograde DiI labeling determined that some of these neurons innervated skeletal muscle. We found that combinations of protons, ATP, and lactate were much more effective than individually applied compounds for activating rapid calcium increases in muscle-innervating dorsal root ganglion neurons. Antagonists for P2X, ASIC, and TRPV1 receptors suggested that these three receptors act together to detect protons, ATP, and lactate when presented together in physiologically relevant concentrations. Two populations of muscle-innervating DRG neurons were found. One responded to low metabolite levels (likely nonnoxious) and used ASIC3, P2X5, and TRPV1 as molecular receptors to detect these metabolites. The other responded to high levels of metabolites (likely noxious) and used ASIC3, P2X4, and TRPV1 as their molecular receptors. We conclude that a combination of ASIC, P2X5 and/or P2X4, and TRPV1 are the molecular receptors used to detect metabolites by muscle-innervating sensory neurons. We further conclude that the adequate stimuli for muscle metaboreceptors and nociceptors are combinations of protons, ATP, and lactate.
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Affiliation(s)
- Alan R Light
- Department of Anethesiology, University of Utah School of Medicine, Salt Lake City, UT 84132-2304, USA.
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Huang SJ, Yang WS, Lin YW, Wang HC, Chen CC. Increase of insulin sensitivity and reversal of age-dependent glucose intolerance with inhibition of ASIC3. Biochem Biophys Res Commun 2008; 371:729-34. [DOI: 10.1016/j.bbrc.2008.04.147] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2008] [Accepted: 04/24/2008] [Indexed: 01/06/2023]
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