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Lin Y, Lee C, Sung J, Chen C. Genetic exploration of roles of acid-sensing ion channel subtypes in neurosensory mechanotransduction including proprioception. Exp Physiol 2024; 109:66-80. [PMID: 37489658 PMCID: PMC10988671 DOI: 10.1113/ep090762] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 07/03/2023] [Indexed: 07/26/2023]
Abstract
Although acid-sensing ion channels (ASICs) are proton-gated ion channels responsible for sensing tissue acidosis, accumulating evidence has shown that ASICs are also involved in neurosensory mechanotransduction. However, in contrast to Piezo ion channels, evidence of ASICs as mechanically gated ion channels has not been found using conventional mechanoclamp approaches. Instead, ASICs are involved in the tether model of mechanotransduction, with the channels gated via tethering elements of extracellular matrix and intracellular cytoskeletons. Methods using substrate deformation-driven neurite stretch and micropipette-guided ultrasound were developed to reveal the roles of ASIC3 and ASIC1a, respectively. Here we summarize the evidence supporting the roles of ASICs in neurosensory mechanotransduction in knockout mouse models of ASIC subtypes and provide insight to further probe their roles in proprioception.
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Affiliation(s)
- Yi‐Chen Lin
- Department of Neurology, Wan Fang HospitalTaipei Medical UniversityTaipeiTaiwan
- The Ph.D. Program for Translational MedicineTaipei Medical University and Academia SinicaNew Taipei CityTaiwan
- Taipei Neuroscience InstituteTaipei Medical UniversityNew Taipei CityTaiwan
- Institute of Biomedical SciencesAcademia SinicaTaipeiTaiwan
| | - Cheng‐Han Lee
- Institute of Biomedical SciencesAcademia SinicaTaipeiTaiwan
- Neuroscience Program of Academia SinicaAcademia SinicaTaipeiTaiwan
| | - Jia‐Ying Sung
- Department of Neurology, Wan Fang HospitalTaipei Medical UniversityTaipeiTaiwan
- Taipei Neuroscience InstituteTaipei Medical UniversityNew Taipei CityTaiwan
- Department of Neurology, School of Medicine, College of MedicineTaipei Medical UniversityTaipeiTaiwan
| | - Chih‐Cheng Chen
- The Ph.D. Program for Translational MedicineTaipei Medical University and Academia SinicaNew Taipei CityTaiwan
- Institute of Biomedical SciencesAcademia SinicaTaipeiTaiwan
- Neuroscience Program of Academia SinicaAcademia SinicaTaipeiTaiwan
- Taiwan Mouse Clinic – National Comprehensive Mouse Phenotyping and Drug Testing CenterAcademia SinicaTaipeiTaiwan
- TMU Neuroscience Research Center, Taipei Medical UniversityNew Taipei CityTaiwan
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2
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Mao XL, Chen YX, Yu H, Yang QW. Inhibition of acid sensing ion channels by eugenol in rat trigeminal ganglion neurons. Neurosci Lett 2023; 803:137192. [PMID: 36924928 DOI: 10.1016/j.neulet.2023.137192] [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: 01/03/2023] [Revised: 03/10/2023] [Accepted: 03/11/2023] [Indexed: 03/17/2023]
Abstract
Eugenol is widely used as an analgesic in the dental treatment. The underlying mechanisms may involve its modulation of various ion channels. Acid-sensing ion channels (ASICs) are pH sensors and expressed in trigeminal ganglion (TG) neurons. In the present study, we found that eugenol concentration-dependently inhibited ASIC currents in TG neurons with an IC50 of 98.8 ± 7.4 μM. Eugenol decreased the maximum response to acidic pH and did not alter pH0.5 in the concentration-response curve of acidic pH, suggesting a noncompetitive inhibition of ASICs by eugenol. G-proteins were not involved in eugenol-induced inhibition, since pre-application of eugenol also decreased ASIC currents in the presence of the G-protein blocker GDP-β-S. In addition, eugenol also partly inhibited ASIC3 currents in Chinese hamster ovary cells transfected with ASIC3. In conclusion, eugenol partly inhibited ASIC currents in TG neurons in a concentration-dependent, non-competitive and G-protein independent manner. These results suggested that the ASICs could be a molecular target for eugenol in TG neurons, which contributed to its analgesic effect.
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Affiliation(s)
- Xiao-Li Mao
- Department of Pharmacy, Wuhan First Hospital, Wuhan, China.
| | - Yi-Xuan Chen
- Department of Pharmacy, Wuhan First Hospital, Wuhan, China
| | - Huan Yu
- Department of Pharmacy, Wuhan First Hospital, Wuhan, China
| | - Quan-Wei Yang
- Department of Pharmacy, Wuhan First Hospital, Wuhan, China.
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3
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Shan Z, Ren C, Gu M, Lin Y, Sum FHKMH, McGrath C, Jin L, Zhang C, Yang Y. Effects of Low-Level Laser Therapy on Dentin Hypersensitivity in Periodontally Compromised Patients Undergoing Orthodontic Treatment: A Randomised Controlled Trial. J Clin Med 2023; 12:1419. [PMID: 36835953 PMCID: PMC9961942 DOI: 10.3390/jcm12041419] [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: 01/06/2023] [Revised: 02/09/2023] [Accepted: 02/09/2023] [Indexed: 02/12/2023] Open
Abstract
OBJECTIVES This study aimed to assess the effects of low-level laser therapy (LLLT) on dentin hypersensitivity (DH) in periodontally compromised patients undergoing orthodontic treatment. METHODS This triple-blinded randomised controlled trial included 143 teeth with DH from 23 periodontally compromised patients. Teeth on one side of the dental arch were randomly assigned to the LLLT group (LG), while those on the contralateral side were allocated to the non-LLLT group (NG). After orthodontic treatment commenced, patients' orthodontic pain (OP) perceptions were documented in pain diaries. DH was assessed chairside by a visual analogue scale (VASDH) at fifteen timepoints across the orthodontic treatment and retention. VASDH scores were compared among timepoints by the Friedman test, among patients with varying OP perceptions using the Kruskal-Wallis tests, and between the LG and NG with the Mann-Whitney U test. RESULTS DH generally decreased over the observation (p < 0.001). The VASDH scores differed among patients with varying OP perceptions at multiple timepoints (p < 0.05). The generalized estimating equation model showed teeth in the LG had a significantly lower VASDH score than the NG at the 3rd month of treatment (p = 0.011). CONCLUSION LLLT could be potentially beneficial in managing DH in periodontally compromised patients undergoing orthodontic treatment.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Yanqi Yang
- Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Sai Ying Pun, Hong Kong SAR, China
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Immune System Acts on Orthodontic Tooth Movement: Cellular and Molecular Mechanisms. BIOMED RESEARCH INTERNATIONAL 2022; 2022:9668610. [PMID: 36330460 PMCID: PMC9626206 DOI: 10.1155/2022/9668610] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 09/05/2022] [Accepted: 09/29/2022] [Indexed: 12/03/2022]
Abstract
Orthodontic tooth movement (OTM) is a tissue remodeling process based on orthodontic force loading. Compressed periodontal tissues have a complicated aseptic inflammatory cascade, which are considered the initial factor of alveolar bone remodeling. Since skeletal and immune systems shared a wide variety of molecules, osteoimmunology has been generally accepted as an interdisciplinary field to investigate their interactions. Unsurprisingly, OTM is considered a good mirror of osteoimmunology since it involves immune reaction and bone remolding. In fact, besides bone remodeling, OTM involves cementum resorption, soft tissue remodeling, orthodontic pain, and relapse, all correlated with immune cells and/or immunologically active substance. The aim of this paper is to review the interaction of immune system with orthodontic tooth movement, which helps gain insights into mechanisms of OTM and search novel method to short treatment period and control complications.
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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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Tang Z, Zhou J, Long H, Gao Y, Wang Q, Li X, Wang Y, Lai W, Jian F. Molecular mechanism in trigeminal nerve and treatment methods related to orthodontic pain. J Oral Rehabil 2021; 49:125-137. [PMID: 34586644 DOI: 10.1111/joor.13263] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 09/02/2021] [Accepted: 09/23/2021] [Indexed: 02/05/2023]
Abstract
BACKGROUND Orthodontic treatment is the main treatment approach for malocclusion. Orthodontic pain is an inevitable undesirable adverse reaction during orthodontic treatment. It is reported orthodontic pain has become one of the most common reason that patients withdraw from orthodontic treatment. Therefore, understanding the underlying mechanism and finding treatment of orthodontic pain are in urgent need. AIMS This article aims to sort out the mechanisms and treatments of orthodontic pain, hoping to provide some ideas for future orthodontic pain relief. MATERIALS Tooth movement will cause local inflammation. Certain inflammatory factors and cytokines stimulating the trigeminal nerve and further generating pain perception, as well as drugs and molecular targeted therapy blocking nerve conduction pathways, will be reviewed in this article. METHOD We review and summaries current studies related to molecular mechanisms and treatment approaches in orthodontic pain control. RESULTS Orthodontics pain related influencing factors and molecular mechanisms has been introduced. Commonly used clinical methods in orthodontic pain control has been evaluated. DISCUSSION With the clarification of more molecular mechanisms, the direction of orthodontic pain treatment will shift to targeted drugs.
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Affiliation(s)
- Ziwei Tang
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jiawei Zhou
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Hu Long
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yanzi Gao
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Qingxuan Wang
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xiaolong Li
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yan Wang
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Wenli Lai
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Fan Jian
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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Middleton SJ, Perez-Sanchez J, Dawes JM. The structure of sensory afferent compartments in health and disease. J Anat 2021; 241:1186-1210. [PMID: 34528255 PMCID: PMC9558153 DOI: 10.1111/joa.13544] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 08/12/2021] [Accepted: 08/30/2021] [Indexed: 12/20/2022] Open
Abstract
Primary sensory neurons are a heterogeneous population of cells able to respond to both innocuous and noxious stimuli. Like most neurons they are highly compartmentalised, allowing them to detect, convey and transfer sensory information. These compartments include specialised sensory endings in the skin, the nodes of Ranvier in myelinated axons, the cell soma and their central terminals in the spinal cord. In this review, we will highlight the importance of these compartments to primary afferent function, describe how these structures are compromised following nerve damage and how this relates to neuropathic pain.
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Affiliation(s)
- Steven J Middleton
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | | | - John M Dawes
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
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Gao M, Yan X, Lu Y, Ren L, Zhang S, Zhang X, Kuang Q, Liu L, Zhou J, Wang Y, Lai W, Long H. Retrograde nerve growth factor signaling modulates tooth mechanical hyperalgesia induced by orthodontic tooth movement via acid-sensing ion channel 3. Int J Oral Sci 2021; 13:18. [PMID: 34088898 PMCID: PMC8178420 DOI: 10.1038/s41368-021-00124-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 04/13/2021] [Accepted: 04/19/2021] [Indexed: 02/07/2023] Open
Abstract
Orthodontic tooth movement elicits alveolar bone remodeling and orofacial pain that is manifested by tooth mechanical hyperalgesia. Nerve growth factor (NGF) is upregulated in periodontium and may modulate tooth mechanical hyperalgesia. The objectives were to examine the role of NGF in tooth mechanical hyperalgesia and to elucidate the underlying mechanisms. Tooth mechanical hyperalgesia was induced by ligating closed coil springs between incisors and molars in Sprague-Dawley rats. Retrograde labeling was performed by periodontal administration of fluor-conjugated NGF and the detection of fluorescence in trigeminal ganglia (TG). Lentivirus vectors carrying NGF shRNA were employed to knockdown the expression of NGF in TG. The administration of agonists, antagonists, and virus vectors into TG and periodontium was conducted. Tooth mechanical hyperalgesia was examined through the threshold of biting withdrawal. Our results revealed that tooth movement elicited tooth mechanical hyperalgesia that could be alleviated by NGF neutralizing antibody and that NGF was upregulated in periodontium (mainly in periodontal fibroblasts) and TG. Retrograde labeling revealed that periodontal NGF was retrogradely transported to TG after day 1. Acid-sensing ion channel 3 (ASIC3) and NGF were co-expressed in trigeminal neurons and the percentage of co-expression was significantly higher following tooth movement. The administration of NGF and NGF neutralizing antibody into TG could upregulate and downregulate the expression of ASIC3 in TG, respectively. NGF aggravated tooth mechanical hyperalgesia that could be alleviated by ASIC3 antagonist (APETx2). Moreover, NGF neutralizing antibody mitigated tooth mechanical hyperalgesia that could be recapitulated by ASIC3 agonist (GMQ). NGF-based gene therapy abolished tooth mechanical hyperalgesia and downregulated ASIC3 expression. Taken together, in response to force stimuli, periodontal fibroblasts upregulated the expressions of NGF that was retrogradely transported to TG, where NGF elicited tooth mechanical hyperalgesia through upregulating ASIC3. NGF-based gene therapy is a viable method in alleviating tooth-movement-induced mechanical hyperalgesia.
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Affiliation(s)
- Meiya Gao
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Orthodontics, Shanxi Provincial People's Hospital, Taiyuan, China
| | - Xinyu Yan
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yanzhu Lu
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Linghuan Ren
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Shizhen Zhang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xiaoqi Zhang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Qianyun Kuang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Lu Liu
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jing Zhou
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yan Wang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Wenli Lai
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
| | - Hu Long
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
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Abstract
Mechanosensing is a key feature through which organisms can receive inputs from the environment and convert them into specific functional and behavioral outputs. Mechanosensation occurs in many cells and tissues, regulating a plethora of molecular processes based on the distribution of forces and stresses both at the cell membrane and at the intracellular organelles levels, through complex interactions between cells’ microstructures, cytoskeleton, and extracellular matrix. Although several primary and secondary mechanisms have been shown to contribute to mechanosensation, a fundamental pathway in simple organisms and mammals involves the presence of specialized sensory neurons and the presence of different types of mechanosensitive ion channels on the neuronal cell membrane. In this contribution, we present a review of the main ion channels which have been proven to be significantly involved in mechanotransduction in neurons. Further, we discuss recent studies focused on the biological mechanisms and modeling of mechanosensitive ion channels’ gating, and on mechanotransduction modeling at different scales and levels of details.
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Pei F, Liu J, Zhang L, Pan X, Huang W, Cen X, Huang S, Jin Y, Zhao Z. The functions of mechanosensitive ion channels in tooth and bone tissues. Cell Signal 2020; 78:109877. [PMID: 33296740 DOI: 10.1016/j.cellsig.2020.109877] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/02/2020] [Accepted: 12/03/2020] [Indexed: 02/08/2023]
Abstract
Tooth and bone are independent tissues with a close relationship. Both are composed of a highly calcified outer structure and soft inner tissue, and both are constantly under mechanical stress. In particular, the alveolar bone and tooth constitute an occlusion system and suffer from masticatory and occlusal force. Thus, mechanotransduction is a key process in many developmental, physiological and pathological processes in tooth and bone. Mechanosensitive ion channels such as Piezo1 and Piezo2 are important participants in mechanotransduction, but their functions in tooth and bone are poorly understood. This review summarizes our current understanding of mechanosensitive ion channels and their roles in tooth and bone tissues. Research in these areas may shed new light on the regulation of tooth and bone tissues and potential treatments for diseases affecting these tissues.
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Affiliation(s)
- Fang Pei
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China School of Stomatology, Sichuan University, Chengdu, PR China
| | - Jialing Liu
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China School of Stomatology, Sichuan University, Chengdu, PR China
| | - Lan Zhang
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China School of Stomatology, Sichuan University, Chengdu, PR China
| | - Xuefeng Pan
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China School of Stomatology, Sichuan University, Chengdu, PR China
| | - Wei Huang
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China School of Stomatology, Sichuan University, Chengdu, PR China
| | - Xiao Cen
- Department of the Temporomandibular Joint, West China Hospital of Stomatology, Sichuan University, Chengdu, PR China
| | - Shishu Huang
- Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, Chengdu, PR China.
| | - Ying Jin
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China School of Stomatology, Sichuan University, Chengdu, PR China.
| | - Zhihe Zhao
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China School of Stomatology, Sichuan University, Chengdu, PR China.
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Hossain MZ, Ando H, Unno S, Kitagawa J. Targeting Chemosensory Ion Channels in Peripheral Swallowing-Related Regions for the Management of Oropharyngeal Dysphagia. Int J Mol Sci 2020; 21:E6214. [PMID: 32867366 PMCID: PMC7503421 DOI: 10.3390/ijms21176214] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 08/24/2020] [Accepted: 08/26/2020] [Indexed: 12/22/2022] Open
Abstract
Oropharyngeal dysphagia, or difficulty in swallowing, is a major health problem that can lead to serious complications, such as pulmonary aspiration, malnutrition, dehydration, and pneumonia. The current clinical management of oropharyngeal dysphagia mainly focuses on compensatory strategies and swallowing exercises/maneuvers; however, studies have suggested their limited effectiveness for recovering swallowing physiology and for promoting neuroplasticity in swallowing-related neuronal networks. Several new and innovative strategies based on neurostimulation in peripheral and cortical swallowing-related regions have been investigated, and appear promising for the management of oropharyngeal dysphagia. The peripheral chemical neurostimulation strategy is one of the innovative strategies, and targets chemosensory ion channels expressed in peripheral swallowing-related regions. A considerable number of animal and human studies, including randomized clinical trials in patients with oropharyngeal dysphagia, have reported improvements in the efficacy, safety, and physiology of swallowing using this strategy. There is also evidence that neuroplasticity is promoted in swallowing-related neuronal networks with this strategy. The targeting of chemosensory ion channels in peripheral swallowing-related regions may therefore be a promising pharmacological treatment strategy for the management of oropharyngeal dysphagia. In this review, we focus on this strategy, including its possible neurophysiological and molecular mechanisms.
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Affiliation(s)
- Mohammad Zakir Hossain
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, 1780 Gobara Hirooka, Shiojiri, Nagano 399-0781, Japan;
| | - Hiroshi Ando
- Department of Biology, School of Dentistry, Matsumoto Dental University, 1780 Gobara, Hirooka, Shiojiri, Nagano 399-0781, Japan;
| | - Shumpei Unno
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, 1780 Gobara Hirooka, Shiojiri, Nagano 399-0781, Japan;
| | - Junichi Kitagawa
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, 1780 Gobara Hirooka, Shiojiri, Nagano 399-0781, Japan;
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The Role of Acid-sensing Ion Channel 3 in the Modulation of Tooth Mechanical Hyperalgesia Induced by Orthodontic Tooth Movement. Neuroscience 2020; 442:274-285. [PMID: 32592826 DOI: 10.1016/j.neuroscience.2020.06.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 06/16/2020] [Accepted: 06/17/2020] [Indexed: 02/05/2023]
Abstract
This study aimed to explore the role of acid-sensing ion channel 3 (ASIC3) in the modulation of tooth mechanical hyperalgesia induced by orthodontic tooth movement. In male Sprague-Dawley rats, closed coil springs were ligated between mandibular incisors and molars to mimic orthodontic tooth movement. Bite force was assessed to evaluate tooth mechanical hyperalgesia. The alveolar bone, trigeminal ganglia, and trigeminal nucleus caudalis underwent immunohistochemical staining and immunoblotting for ASIC3. The inferior alveolar nerves were transected to explore the interaction between the periodontal sensory endings and trigeminal ganglia. The role of ASIC3 in trigeminal ganglia was further explored with lentivirus-mediated ASIC3 ribonucleic acid interference. Results showed that ASIC3 was expressed in the periodontal Ruffini endings and expression of ASIC3 protein was elevated in periodontal tissues, trigeminal ganglia, and trigeminal nucleus caudalis, following orthodontic tooth movement. ASIC3 agonists and antagonists significantly aggravated and mitigated tooth mechanical hyperalgesia, respectively. ASIC3 expression decreased after inferior alveolar nerve transection in periodontal tissues. Both in vitro and vivo, the lentivirus vector carrying ASIC3 shRNA inhibited ASIC3 expression and relieved tooth mechanical hyperalgesia. To conclude, ASIC3 is important in the modulation of tooth mechanical hyperalgesia induced by orthodontic tooth movement. Further, the role of ASIC3 in the modulation of pain in periodontal tissues is regulated by trigeminal ganglia. An adjuvant analgesic therapy targeting ASIC3 could alleviate orthodontic movement-associated mechanical hyperalgesia in rats.
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Hossain MZ, Ando H, Unno S, Nakamoto T, Kitagawa J. Functional involvement of acid-sensing ion channel 3 in the swallowing reflex in rats. Neurogastroenterol Motil 2020; 32:e13728. [PMID: 31565832 DOI: 10.1111/nmo.13728] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 08/20/2019] [Accepted: 09/05/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND Difficulty swallowing represents a major health problem. Swallowing function is improved by incorporating weak acids in suspensions/food boluses, implicating acid-sensing ion channels (ASICs) in the swallowing reflex. However, the functional involvement of ASICs in the swallowing reflex has not been fully elucidated. METHODS We localized ASIC3s in swallowing-related regions innervated by the superior laryngeal nerves (SLNs) and those in the nodose-petrosal-jugular ganglionic complex (NPJc) and examined their functional involvement in evoking the swallowing reflex in rats. KEY RESULTS We localized ASIC3s on epithelial cells and nerve fibers in swallowing-related regions innervated by the SLNs. In the NPJc, around half of the SLN-afferent neurons expressed ASIC3. Two-thirds of ASIC3s were localized on unmyelinated neurons in the nodose and petrosal ganglia. In the jugular ganglia, they were equally distributed on unmyelinated and myelinated neurons. Topical application of a synthetic non-proton ASIC3 activator, 2-guanidine-4-methylquinazoline (GMQ), and its natural endogenous ligand agmatine (a metabolite of the amino acid arginine) in swallowing-related regions evoked a considerable number of swallowing reflexes. Increasing the concentration of GMQ and agmatine up to a certain concentration increased the number of evoked reflexes and shortened the interval between the evoked reflexes. Agmatine was less potent than GMQ in its ability to evoke swallowing reflexes. Prior topical application of an ASIC3 antagonist significantly attenuated the number of GMQ- and agmatine-evoked swallowing reflexes. CONCLUSIONS & INFERENCES Acid-sensing ion channel 3s localized on nerves and epithelial cells in swallowing-related regions are functional in evoking the swallowing reflex and activation of these channels via a pharmacological agonist appears to improve swallowing behavior.
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Affiliation(s)
- Mohammad Zakir Hossain
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, Shiojiri, Japan
| | - Hiroshi Ando
- Department of Biology, Institute for Oral Science, Matsumoto Dental University, Shiojiri, Japan
| | - Shumpei Unno
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, Shiojiri, Japan
| | - Tetsuji Nakamoto
- Division of Oral Pathogenesis and Disease Control, Department of Oral Implantology, Asahi University School of Dentistry, Mizuho, Japan
| | - Junichi Kitagawa
- Department of Oral Physiology, School of Dentistry, Matsumoto Dental University, Shiojiri, Japan
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Gazerani P, Cairns BE. Activation of rat masticatory muscle afferent fibres by acidic pH. Somatosens Mot Res 2018; 35:86-94. [PMID: 29848210 DOI: 10.1080/08990220.2018.1473246] [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: 10/14/2022]
Abstract
Previous research findings have suggested an important role for acid sensing ion channels (ASICs) in muscle pain mechanisms. This study was conducted to determine if masticatory muscle afferent fibres express ASICs, if there are sex differences in this expression, and to compare the effects of low pH and hypertonic saline on afferent fibres that innervate the masticatory muscle in vivo. Immunohistochemistry methods were applied to examine the expression of ASICs in trigeminal ganglion neurons, while in vivo electrophysiology techniques were employed to examine changes in masticatory muscle afferent fibre excitability. Both ASIC1 and ASIC3 were expressed by predominantly larger masticatory muscle ganglion neurons, but the frequency of ASIC3 expression (56%) was significantly greater than ASIC1 (35%). No sex-related differences in expression were identified. Injection of pH 5.8, but not pH 6.8, phosphate buffered saline evoked afferent discharges that were significantly greater than those evoked by pH 7.4 buffer (control). Since ASIC3 channels are not activated until the pH is around 6, these results indicate that activation of both channels contributes to excitation of masticatory muscle afferent fibres. The results further show that many masticatory muscle afferent fibres, which respond to low pH, are low threshold mechanoreceptors. These findings may explain why injection of low pH solutions into the masticatory muscles of healthy humans is not associated with significant muscle pain.
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Affiliation(s)
- Parisa Gazerani
- a Department of Health Science and Technology, Faculty of Medicine , Aalborg University , Aalborg East , Denmark
| | - Brian Edwin Cairns
- a Department of Health Science and Technology, Faculty of Medicine , Aalborg University , Aalborg East , Denmark.,b Faculty of Pharmaceutical Sciences , The University of British Columbia , Vancouver , Canada
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15
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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: 84] [Impact Index Per Article: 14.0] [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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16
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Tsubouchi A, Yano T, Yokoyama TK, Murtin C, Otsuna H, Ito K. Topological and modality-specific representation of somatosensory information in the fly brain. Science 2018; 358:615-623. [PMID: 29097543 DOI: 10.1126/science.aan4428] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 09/25/2017] [Indexed: 12/11/2022]
Abstract
Insects and mammals share similarities of neural organization underlying the perception of odors, taste, vision, sound, and gravity. We observed that insect somatosensation also corresponds to that of mammals. In Drosophila, the projections of all the somatosensory neuron types to the insect's equivalent of the spinal cord segregated into modality-specific layers comparable to those in mammals. Some sensory neurons innervate the ventral brain directly to form modality-specific and topological somatosensory maps. Ascending interneurons with dendrites in matching layers of the nerve cord send axons that converge to respective brain regions. Pathways arising from leg somatosensory neurons encode distinct qualities of leg movement information and play different roles in ground detection. Establishment of the ground pattern and genetic tools for neuronal manipulation should provide the basis for elucidating the mechanisms underlying somatosensation.
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Affiliation(s)
- Asako Tsubouchi
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi, Bunkyo-ku, 113-0032 Tokyo, Japan
| | - Tomoko Yano
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi, Bunkyo-ku, 113-0032 Tokyo, Japan.,Department of Computational Biology, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, 277-0882 Chiba, Japan
| | - Takeshi K Yokoyama
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi, Bunkyo-ku, 113-0032 Tokyo, Japan
| | - Chloé Murtin
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi, Bunkyo-ku, 113-0032 Tokyo, Japan.,Department of Computational Biology, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, 277-0882 Chiba, Japan
| | - Hideo Otsuna
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA
| | - Kei Ito
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi, Bunkyo-ku, 113-0032 Tokyo, Japan. .,Department of Computational Biology, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, 277-0882 Chiba, Japan.,Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA.,Institute of Zoology, University of Cologne, 50674 Cologne, Germany
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17
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Piancino MG, Isola G, Cannavale R, Cutroneo G, Vermiglio G, Bracco P, Anastasi GP. From periodontal mechanoreceptors to chewing motor control: A systematic review. Arch Oral Biol 2017; 78:109-121. [PMID: 28226300 DOI: 10.1016/j.archoralbio.2017.02.010] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 01/29/2017] [Accepted: 02/07/2017] [Indexed: 02/07/2023]
Abstract
PURPOSE This critical review summarizes the current knowledge of the structural and functional characteristics of periodontal mechanoreceptors, and understands their role in the signal pathways and functional motor control. METHOD A systematic review of the literature was conducted. Original articles were searched through Pubmed, Cochrane Central database and Embase until january 2016. RESULT 1466 articles were identified through database searching and screened by reviewing the abstracts. 160 full-text were assessed for eligibility, and after 109 exclusion, 51 articles were included in the review process. Studies selected by the review process were mainly divided in studies on animal and studies on humans. Morphological, histological, molecular and electrophysiological studies investigating the periodontal mechanoreceptors in animals and in humans were included, evaluated and described. CONCLUSION Our knowledge of the periodontal mechanoreceptors, let us conclude that they are very refined neural receptors, deeply involved in the activation and coordination of the masticatory muscles during function. Strictly linked to the rigid structure of the teeth, they determine all the functional physiological and pathological processes of the stomatognathic system. The knowledge of their complex features is fundamental for all dental professionists. Further investigations are of utmost importance for guiding the technological advances in the respect of the neural control in the dental field.
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Affiliation(s)
- Maria Grazia Piancino
- Department of Orthodontics and Gnathology-Masticatory Function, Turin University, Italy.
| | - Gaetano Isola
- Department of Orthodontics and Gnathology-Masticatory Function, Turin University, Italy
| | - Rosangela Cannavale
- Department of Orthodontics and Gnathology-Masticatory Function, Turin University, Italy
| | - Giuseppina Cutroneo
- Department of Biomedical Sciences and Morphological and Functional Images, Messina University, Italy
| | - Giovanna Vermiglio
- Department of Biomedical Sciences and Morphological and Functional Images, Messina University, Italy
| | - Pietro Bracco
- Department of Orthodontics and Gnathology-Masticatory Function, Turin University, Italy
| | - Giuseppe Pio Anastasi
- Department of Biomedical Sciences and Morphological and Functional Images, Messina University, Italy
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18
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Long H, Wang Y, Jian F, Liao LN, Yang X, Lai WL. Current advances in orthodontic pain. Int J Oral Sci 2016; 8:67-75. [PMID: 27341389 PMCID: PMC4932774 DOI: 10.1038/ijos.2016.24] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/11/2016] [Indexed: 02/05/2023] Open
Abstract
Orthodontic pain is an inflammatory pain that is initiated by orthodontic force-induced vascular occlusion followed by a cascade of inflammatory responses, including vascular changes, the recruitment of inflammatory and immune cells, and the release of neurogenic and pro-inflammatory mediators. Ultimately, endogenous analgesic mechanisms check the inflammatory response and the sensation of pain subsides. The orthodontic pain signal, once received by periodontal sensory endings, reaches the sensory cortex for pain perception through three-order neurons: the trigeminal neuron at the trigeminal ganglia, the trigeminal nucleus caudalis at the medulla oblongata and the ventroposterior nucleus at the thalamus. Many brain areas participate in the emotion, cognition and memory of orthodontic pain, including the insular cortex, amygdala, hippocampus, locus coeruleus and hypothalamus. A built-in analgesic neural pathway—periaqueductal grey and dorsal raphe—has an important role in alleviating orthodontic pain. Currently, several treatment modalities have been applied for the relief of orthodontic pain, including pharmacological, mechanical and behavioural approaches and low-level laser therapy. The effectiveness of nonsteroidal anti-inflammatory drugs for pain relief has been validated, but its effects on tooth movement are controversial. However, more studies are needed to verify the effectiveness of other modalities. Furthermore, gene therapy is a novel, viable and promising modality for alleviating orthodontic pain in the future.
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Affiliation(s)
- Hu Long
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yan Wang
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Fan Jian
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Li-Na Liao
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xin Yang
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Wen-Li Lai
- State Key Laboratory of Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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19
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Gao M, Long H, Ma W, Liao L, Yang X, Zhou Y, Shan D, Huang R, Jian F, Wang Y, Lai W. The role of periodontal ASIC3 in orofacial pain induced by experimental tooth movement in rats. Eur J Orthod 2015; 38:577-583. [DOI: 10.1093/ejo/cjv082] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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20
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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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21
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Cabo R, Alonso P, Viña E, Vázquez G, Gago A, Feito J, Pérez-Moltó FJ, García-Suárez O, Vega JA. ASIC2 is present in human mechanosensory neurons of the dorsal root ganglia and in mechanoreceptors of the glabrous skin. Histochem Cell Biol 2014; 143:267-76. [DOI: 10.1007/s00418-014-1278-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/02/2014] [Indexed: 01/23/2023]
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22
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Abstract
The somatosensory system decodes a wide range of tactile stimuli and thus endows us with a remarkable capacity for object recognition, texture discrimination, sensory-motor feedback and social exchange. The first step leading to perception of innocuous touch is activation of cutaneous sensory neurons called low-threshold mechanoreceptors (LTMRs). Here, we review the properties and functions of LTMRs, emphasizing the unique tuning properties of LTMR subtypes and the organizational logic of their peripheral and central axonal projections. We discuss the spinal cord neurophysiological representation of complex mechanical forces acting upon the skin and current views of how tactile information is processed and conveyed from the spinal cord to the brain. An integrative model in which ensembles of impulses arising from physiologically distinct LTMRs are integrated and processed in somatotopically aligned mechanosensory columns of the spinal cord dorsal horn underlies the nervous system's enormous capacity for perceiving the richness of the tactile world.
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Affiliation(s)
- Victoria E Abraira
- The Solomon H. Snyder Department of Neuroscience, Howard Hughes Medical Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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23
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Roudaut Y, Lonigro A, Coste B, Hao J, Delmas P, Crest M. Touch sense: functional organization and molecular determinants of mechanosensitive receptors. Channels (Austin) 2013; 6:234-45. [PMID: 23146937 DOI: 10.4161/chan.22213] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Cutaneous mechanoreceptors are localized in the various layers of the skin where they detect a wide range of mechanical stimuli, including light brush, stretch, vibration and noxious pressure. This variety of stimuli is matched by a diverse array of specialized mechanoreceptors that respond to cutaneous deformation in a specific way and relay these stimuli to higher brain structures. Studies across mechanoreceptors and genetically tractable sensory nerve endings are beginning to uncover touch sensation mechanisms. Work in this field has provided researchers with a more thorough understanding of the circuit organization underlying the perception of touch. Novel ion channels have emerged as candidates for transduction molecules and properties of mechanically gated currents improved our understanding of the mechanisms of adaptation to tactile stimuli. This review highlights the progress made in characterizing functional properties of mechanoreceptors in hairy and glabrous skin and ion channels that detect mechanical inputs and shape mechanoreceptor adaptation.
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Affiliation(s)
- Yann Roudaut
- Aix-Marseille Université, CNRS, Marseille, France
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24
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Chen CC, Wong CW. Neurosensory mechanotransduction through acid-sensing ion channels. J Cell Mol Med 2013; 17:337-49. [PMID: 23490035 PMCID: PMC3823015 DOI: 10.1111/jcmm.12025] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Accepted: 12/28/2012] [Indexed: 02/06/2023] Open
Abstract
Acid-sensing ion channels (ASICs) are voltage-insensitive cation channels responding to extracellular acidification. ASIC proteins have two transmembrane domains and a large extracellular domain. The molecular topology of ASICs is similar to that of the mechanosensory abnormality 4- or 10-proteins expressed in touch receptor neurons and involved in neurosensory mechanotransduction in nematodes. The ASIC proteins are involved in neurosensory mechanotransduction in mammals. The ASIC isoforms are expressed in Merkel cell-neurite complexes, periodontal Ruffini endings and specialized nerve terminals of skin and muscle spindles, so they might participate in mechanosensation. In knockout mouse models, lacking an ASIC isoform produces defects in neurosensory mechanotransduction of tissue such as skin, stomach, colon, aortic arch, venoatrial junction and cochlea. The ASICs are thus implicated in touch, pain, digestive function, baroreception, blood volume control and hearing. However, the role of ASICs in mechanotransduction is still controversial, because we lack evidence that the channels are mechanically sensitive when expressed in heterologous cells. Thus, ASIC channels alone are not sufficient to reconstruct the path of transducing molecules of mechanically activated channels. The mechanotransducers associated with ASICs need further elucidation. In this review, we discuss the expression of ASICs in sensory afferents of mechanoreceptors, findings of knockout studies, technical issues concerning studies of neurosensory mechanotransduction and possible missing links. Also we propose a molecular model and a new approach to disclose the molecular mechanism underlying the neurosensory mechanotransduction.
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Affiliation(s)
- Chih-Cheng Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.
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25
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Cabo R, Gálvez A, Laurà R, San José I, Pastor J, López-Muñiz A, García-Suárez O, Vega J. Immunohistochemical Detection of the Putative Mechanoproteins ASIC2 and TRPV4 in Avian Herbst Sensory Corpuscles. Anat Rec (Hoboken) 2012; 296:117-22. [DOI: 10.1002/ar.22615] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2012] [Revised: 07/06/2012] [Accepted: 07/29/2012] [Indexed: 12/20/2022]
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26
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Cabo R, Gálvez MA, San José I, Laurà R, López-Muñiz A, García-Suárez O, Cobo T, Insausti R, Vega JA. Immunohistochemical localization of acid-sensing ion channel 2 (ASIC2) in cutaneous Meissner and Pacinian corpuscles of Macaca fascicularis. Neurosci Lett 2012; 516:197-201. [PMID: 22708125 DOI: 10.1016/j.neulet.2012.03.081] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Acid-sensing ion channel 2 (ASIC2) is a member of the degenerin/epithelial sodium channel superfamily, presumably involved mechanosensation. Expression of ASIC2 has been detected in mechanosensory neurons as well as in both axons and Schwann-like cells of cutaneous mechanoreceptors. In these studies we analysed expression of ASIC2 in the cutaneous sensory corpuscles of Macaca fascicularis using immunohistochemistry and laser confocal-scanner microscopy. ASIC2 immunoreactivity was detected in both Meissner and Pacinian corpuscles. It was found to co-localize with neuron-specific enolase and RT-97, but not with S100 protein, demonstrating that ASIC2 expression is restricted to axons supplying mechanoreceptors. These results demonstrate for the first time the presence of the protein ASIC2 in cutaneous rapidly adapting low-threshold mechanoreceptors of monkey, suggesting a role of this ion channel in touch sense.
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Affiliation(s)
- R Cabo
- Departamento de Morfología y Biología Celular, Universidad de Oviedo, Spain
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27
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Del Valle ME, Cobo T, Cobo JL, Vega JA. Mechanosensory neurons, cutaneous mechanoreceptors, and putative mechanoproteins. Microsc Res Tech 2012; 75:1033-43. [PMID: 22461425 DOI: 10.1002/jemt.22028] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 01/31/2012] [Indexed: 01/16/2023]
Abstract
The mammalian skin has developed sensory structures (mechanoreceptors) that are responsible for different modalities of mechanosensitivity like touch, vibration, and pressure sensation. These specialized sensory organs are anatomically and functionally connected to a special subset of sensory neurons called mechanosensory neurons, which electrophysiologically correspond with Aβ fibers. Although mechanosensory neurons and cutaneous mechanoreceptors are rather well known, the biology of the sense of touch still remains poorly understood. Basically, the process of mechanosensitivity requires the conversion of a mechanical stimulus into an electrical signal through the activation of ion channels that gate in response to mechanical stimuli. These ion channels belong primarily to the family of the degenerin/epithelium sodium channels, especially the subfamily acid-sensing ion channels, and to the family of transient receptor potential channels. This review compiles the current knowledge on the occurrence of putative mechanoproteins in mechanosensory neurons and mechanoreceptors, as well as the involvement of these proteins on the biology of touch. Furthermore, we include a section about what the knock-out mice for mechanoproteins are teaching us. Finally, the possibilities for mechanotransduction in mechanoreceptors, and the common involvement of the ion channels, extracellular membrane, and cytoskeleton, are revisited.
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Affiliation(s)
- M E Del Valle
- Departamento de Morfología y Biología Celular, Universidad de Oviedo, Oviedo, Spain
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28
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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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