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Zhang Y, Dong D, Zhang J, Cheng K, Zhen F, Li M, Chen B. Pathology and physiology of acid-sensitive ion channels in the bladder. Heliyon 2024; 10:e38031. [PMID: 39347393 PMCID: PMC11437851 DOI: 10.1016/j.heliyon.2024.e38031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 08/08/2024] [Accepted: 09/16/2024] [Indexed: 10/01/2024] Open
Abstract
Acid-sensitive ion channels (ASICs) are sodium-permeable channels activated by extracellular acidification. They can be activated and trigger the inward flow of Na+ when the extracellular environment is acidic, leading to membrane depolarization and thus inducing action potentials in neurons. There are four ASIC genes in mammals (ASIC1-4). ASIC is widely expressed in humans. It is closely associated with pain, neurological disorders, multiple sclerosis, epilepsy, migraines, and many other disorders. Bladder pain syndrome/interstitial cystitis (BPS/IC) is a specific syndrome characterized by bladder pain. Recent studies have shown that ASICs are closely associated with the development of BPS/IC. A study revealed that ASIC levels are significantly elevated in a BPS/IC model. Additionally, researchers have reported differential changes in ASICs in the bladders of patients with neurogenic lower urinary tract dysfunction (NLUTD) caused by spinal cord injury (SCI). In this review, we summarize the structure and physiological functions of ASICs and focus on the mechanisms by which ASICs mediate bladder disease.
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Affiliation(s)
- Yang Zhang
- Department of Urology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Di Dong
- Department of Urology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Jialong Zhang
- Department of Urology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Kang Cheng
- Department of Urology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Fang Zhen
- Department of Pathology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Mei Li
- Department of Pathology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Binghai Chen
- Department of Urology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
- Institute of Translational Medicine, Jiangsu University, China
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Olov N, Nour S, Harris AR, Li D, Cook M, Williams RJ, Cheeseman S, Nisbet DR. Using Nanoscale Passports To Understand and Unlock Ion Channels as Gatekeepers of the Cell. ACS NANO 2024; 18:22709-22733. [PMID: 39136685 DOI: 10.1021/acsnano.4c05654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/28/2024]
Abstract
Natural ion channels are proteins embedded in the cell membrane that control many aspects of cell and human physiology by acting as gatekeepers, regulating the flow of ions in and out of cells. Advances in nanotechnology have influenced the methods for studying ion channels in vitro, as well as ways to unlock the delivery of therapeutics by modulating them in vivo. This review provides an overview of nanotechnology-enabled approaches for ion channel research with a focus on the synthesis and applications of synthetic ion channels. Further, the uses of nanotechnology for therapeutic applications are critically analyzed. Finally, we provide an outlook on the opportunities and challenges at the intersection of nanotechnology and ion channels. This work highlights the key role of nanoscale interactions in the operation and modulation of ion channels, which may prompt insights into nanotechnology-enabled mechanisms to study and exploit these systems in the near future.
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Affiliation(s)
- Nafiseh Olov
- Department of Biomedical Engineering, Faculty of Engineering and Information Technology, The University of Melbourne, Parkville, VIC 3010, Melbourne, Australia
- The Graeme Clark Institute, The University of Melbourne, Parkville, VIC 3010, Melbourne, Australia
| | - Shirin Nour
- Department of Biomedical Engineering, Faculty of Engineering and Information Technology, The University of Melbourne, Parkville, VIC 3010, Melbourne, Australia
- The Graeme Clark Institute, The University of Melbourne, Parkville, VIC 3010, Melbourne, Australia
- Polymer Science Group, Department of Chemical Engineering, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Alexander R Harris
- Department of Biomedical Engineering, Faculty of Engineering and Information Technology, The University of Melbourne, Parkville, VIC 3010, Melbourne, Australia
| | - Dan Li
- Department of Chemical Engineering, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Mark Cook
- Department of Biomedical Engineering, Faculty of Engineering and Information Technology, The University of Melbourne, Parkville, VIC 3010, Melbourne, Australia
- The Graeme Clark Institute, The University of Melbourne, Parkville, VIC 3010, Melbourne, Australia
- Department of Medicine, St Vincent's Hospital, Melbourne, Fitzroy, VIC 3065, Australia
| | - Richard J Williams
- The Graeme Clark Institute, The University of Melbourne, Parkville, VIC 3010, Melbourne, Australia
- Centre for Sustainable Bioproducts, Deakin University, Waurn Ponds, VIC 3217, Australia
- IMPACT, School of Medicine, Deakin University, Waurn Ponds, VIC 3217, Australia
| | - Samuel Cheeseman
- Department of Biomedical Engineering, Faculty of Engineering and Information Technology, The University of Melbourne, Parkville, VIC 3010, Melbourne, Australia
- The Graeme Clark Institute, The University of Melbourne, Parkville, VIC 3010, Melbourne, Australia
| | - David R Nisbet
- Department of Biomedical Engineering, Faculty of Engineering and Information Technology, The University of Melbourne, Parkville, VIC 3010, Melbourne, Australia
- The Graeme Clark Institute, The University of Melbourne, Parkville, VIC 3010, Melbourne, Australia
- Medical School, Faculty of Medicine, Dentistry and Health Science, The University of Melbourne, Parkville, VIC 3010, Melbourne, Australia
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Shi X, Liu R, Wang Y, Yu T, Zhang K, Zhang C, Gu Y, Zhang L, Wu J, Wang Q, Zhu F. Inhibiting acid-sensing ion channel exerts neuroprotective effects in experimental epilepsy via suppressing ferroptosis. CNS Neurosci Ther 2024; 30:e14596. [PMID: 38357854 PMCID: PMC10867794 DOI: 10.1111/cns.14596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 12/16/2023] [Accepted: 12/21/2023] [Indexed: 02/16/2024] Open
Abstract
BACKGROUND Epilepsy is a chronic neurological disease characterized by repeated and unprovoked epileptic seizures. Developing disease-modifying therapies (DMTs) has become important in epilepsy studies. Notably, focusing on iron metabolism and ferroptosis might be a strategy of DMTs for epilepsy. Blocking the acid-sensing ion channel 1a (ASIC1a) has been reported to protect the brain from ischemic injury by reducing the toxicity of [Ca2+ ]i . However, whether inhibiting ASIC1a could exert neuroprotective effects and become a novel target for DMTs, such as rescuing the ferroptosis following epilepsy, remains unknown. METHODS In our study, we explored the changes in ferroptosis-related indices, including glutathione peroxidase (GPx) enzyme activity and levels of glutathione (GSH), iron accumulation, lipid degradation products-malonaldehyde (MDA) and 4-hydroxynonenal (4-HNE) by collecting peripheral blood samples from adult patients with epilepsy. Meanwhile, we observed alterations in ASIC1a protein expression and mitochondrial microstructure in the epileptogenic foci of patients with drug-resistant epilepsy. Next, we accessed the expression and function changes of ASIC1a and measured the ferroptosis-related indices in the in vitro 0-Mg2+ model of epilepsy with primary cultured neurons. Subsequently, we examined whether blocking ASIC1a could play a neuroprotective role by inhibiting ferroptosis in epileptic neurons. RESULTS Our study first reported significant changes in ferroptosis-related indices, including reduced GPx enzyme activity, decreased levels of GSH, iron accumulation, elevated MDA and 4-HNE, and representative mitochondrial crinkling in adult patients with epilepsy, especially in epileptogenic foci. Furthermore, we found that inhibiting ASIC1a could produce an inhibitory effect similar to ferroptosis inhibitor Fer-1, alleviate oxidative stress response, and decrease [Ca2+ ]i overload by inhibiting the overexpressed ASIC1a in the in vitro epilepsy model induced by 0-Mg2+ . CONCLUSION Inhibiting ASIC1a has potent neuroprotective effects via alleviating [Ca2+ ]i overload and regulating ferroptosis on the models of epilepsy and may act as a promising intervention in DMTs.
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Affiliation(s)
- Xiaorui Shi
- Department of Neurology, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
- China National Clinical Research Center for Neurological DiseasesBeijingChina
| | - Ru Liu
- Department of Neurology, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
- China National Clinical Research Center for Neurological DiseasesBeijingChina
- Advanced Innovation Center for Human Brain ProtectionCapital Medical UniversityBeijingChina
| | - Yingting Wang
- Department of Neurology, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
- China National Clinical Research Center for Neurological DiseasesBeijingChina
| | - Tingting Yu
- Department of Neurology, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
- China National Clinical Research Center for Neurological DiseasesBeijingChina
| | - Kai Zhang
- Department of Neurology, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
- Department of Neurosurgery, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
| | - Chao Zhang
- Department of Neurology, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
- Department of Neurosurgery, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
| | - Yuyu Gu
- Department of Neurology, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
| | - Limin Zhang
- Department of Neurology, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
| | - Jianping Wu
- Department of Neurology, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
- China National Clinical Research Center for Neurological DiseasesBeijingChina
- Advanced Innovation Center for Human Brain ProtectionCapital Medical UniversityBeijingChina
| | - Qun Wang
- Department of Neurology, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
- China National Clinical Research Center for Neurological DiseasesBeijingChina
- Center of Epilepsy, Beijing Institute of Brain Disorders, Collaborative Innovation Center for Brain DisordersCapital Medical UniversityBeijingChina
| | - Fei Zhu
- Department of Neurology, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
- China National Clinical Research Center for Neurological DiseasesBeijingChina
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Verkest C, Salinas M, Diochot S, Deval E, Lingueglia E, Baron A. Mechanisms of Action of the Peptide Toxins Targeting Human and Rodent Acid-Sensing Ion Channels and Relevance to Their In Vivo Analgesic Effects. Toxins (Basel) 2022; 14:toxins14100709. [PMID: 36287977 PMCID: PMC9612379 DOI: 10.3390/toxins14100709] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 09/30/2022] [Accepted: 10/02/2022] [Indexed: 11/16/2022] Open
Abstract
Acid-sensing ion channels (ASICs) are voltage-independent H+-gated cation channels largely expressed in the nervous system of rodents and humans. At least six isoforms (ASIC1a, 1b, 2a, 2b, 3 and 4) associate into homotrimers or heterotrimers to form functional channels with highly pH-dependent gating properties. This review provides an update on the pharmacological profiles of animal peptide toxins targeting ASICs, including PcTx1 from tarantula and related spider toxins, APETx2 and APETx-like peptides from sea anemone, and mambalgin from snake, as well as the dimeric protein snake toxin MitTx that have all been instrumental to understanding the structure and the pH-dependent gating of rodent and human cloned ASICs and to study the physiological and pathological roles of native ASICs in vitro and in vivo. ASICs are expressed all along the pain pathways and the pharmacological data clearly support a role for these channels in pain. ASIC-targeting peptide toxins interfere with ASIC gating by complex and pH-dependent mechanisms sometimes leading to opposite effects. However, these dual pH-dependent effects of ASIC-inhibiting toxins (PcTx1, mambalgin and APETx2) are fully compatible with, and even support, their analgesic effects in vivo, both in the central and the peripheral nervous system, as well as potential effects in humans.
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Affiliation(s)
- Clément Verkest
- CNRS (Centre National de la Recherche Scientifique), IPMC (Institut de Pharmacologie Moléculaire et Cellulaire), LabEx ICST (Laboratory of Excellence in Ion Channel Science and Therapeutics), FHU InovPain (Fédération Hospitalo-Universitaire “Innovative Solutions in Refractory Chronic Pain”), Université Côte d’Azur, 660 Route des Lucioles, Sophia-Antipolis, 06560 Nice, France
- Department of Anesthesiology, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Miguel Salinas
- CNRS (Centre National de la Recherche Scientifique), IPMC (Institut de Pharmacologie Moléculaire et Cellulaire), LabEx ICST (Laboratory of Excellence in Ion Channel Science and Therapeutics), FHU InovPain (Fédération Hospitalo-Universitaire “Innovative Solutions in Refractory Chronic Pain”), Université Côte d’Azur, 660 Route des Lucioles, Sophia-Antipolis, 06560 Nice, France
| | - Sylvie Diochot
- CNRS (Centre National de la Recherche Scientifique), IPMC (Institut de Pharmacologie Moléculaire et Cellulaire), LabEx ICST (Laboratory of Excellence in Ion Channel Science and Therapeutics), FHU InovPain (Fédération Hospitalo-Universitaire “Innovative Solutions in Refractory Chronic Pain”), Université Côte d’Azur, 660 Route des Lucioles, Sophia-Antipolis, 06560 Nice, France
| | - Emmanuel Deval
- CNRS (Centre National de la Recherche Scientifique), IPMC (Institut de Pharmacologie Moléculaire et Cellulaire), LabEx ICST (Laboratory of Excellence in Ion Channel Science and Therapeutics), FHU InovPain (Fédération Hospitalo-Universitaire “Innovative Solutions in Refractory Chronic Pain”), Université Côte d’Azur, 660 Route des Lucioles, Sophia-Antipolis, 06560 Nice, France
| | - Eric Lingueglia
- CNRS (Centre National de la Recherche Scientifique), IPMC (Institut de Pharmacologie Moléculaire et Cellulaire), LabEx ICST (Laboratory of Excellence in Ion Channel Science and Therapeutics), FHU InovPain (Fédération Hospitalo-Universitaire “Innovative Solutions in Refractory Chronic Pain”), Université Côte d’Azur, 660 Route des Lucioles, Sophia-Antipolis, 06560 Nice, France
| | - Anne Baron
- CNRS (Centre National de la Recherche Scientifique), IPMC (Institut de Pharmacologie Moléculaire et Cellulaire), LabEx ICST (Laboratory of Excellence in Ion Channel Science and Therapeutics), FHU InovPain (Fédération Hospitalo-Universitaire “Innovative Solutions in Refractory Chronic Pain”), Université Côte d’Azur, 660 Route des Lucioles, Sophia-Antipolis, 06560 Nice, France
- Correspondence:
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Zhu Y, Hu X, Wang L, Zhang J, Pan X, Li Y, Cao R, Li B, Lin H, Wang Y, Zuo L, Huang Y. Recent Advances in Acid-sensitive Ion Channels in Central Nervous System Diseases. Curr Pharm Des 2022; 28:1406-1411. [PMID: 35466865 DOI: 10.2174/1381612828666220422084159] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 02/24/2022] [Indexed: 11/22/2022]
Abstract
Acid-sensitive ion channels (ASICs) are cationic channels activated by extracellular protons and widely distributed in the nervous system of mammals. It belongs to the ENaC/DEG family and has four coding genes: ASIC1, ASIC2, ASIC3, and ASIC4, which encode eight subunit proteins: ASIC1a, ASIC1b, ASIC1b2, ASIC2a, ASIC2b, ASIC3, ASIC4, and ASIC5. Different subtypes of ASICs have different distributions in the central nervous system, and they play an important role in various physiological and pathological processes of the central nervous system, including synaptic plasticity, anxiety disorders, fear conditioning, depression-related behavior, epilepsy, Alzheimer's disease, Parkinson's disease, Huntington's disease, multiple sclerosis, malignant Glioma, pain, and others. This paper reviewed the recent studies of ASICs on the central nervous system to improve the understanding of ASICs' physiological functions and pathological effects. This article also provides a reference for studying the molecular mechanisms and therapeutic measures of nervous system-related diseases.
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Affiliation(s)
- Yueqin Zhu
- Department of Pharmacy, West Branch of The First Affiliated Hospital of University of Science and Technology of China (Anhui Provincial Cancer Hospital), Hefei, 230031, China
| | - Xiaojie Hu
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Lili Wang
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Jin Zhang
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Xuesheng Pan
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Yangyang Li
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Rui Cao
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Bowen Li
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Huimin Lin
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Yanan Wang
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
| | - Longquan Zuo
- Department of Pharmacy, Hospital of Armed Police of Anhui Province, Hefei 230061, Anhui, China
| | - Yan Huang
- School of Pharmacy, Anhui Medical University, Hefei 230022, Anhui, China
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Sivils A, Yang F, Wang JQ, Chu XP. Acid-Sensing Ion Channel 2: Function and Modulation. MEMBRANES 2022; 12:membranes12020113. [PMID: 35207035 PMCID: PMC8880099 DOI: 10.3390/membranes12020113] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/14/2022] [Accepted: 01/17/2022] [Indexed: 01/08/2023]
Abstract
Acid-sensing ion channels (ASICs) have an important influence on human physiology and pathology. They are members of the degenerin/epithelial sodium channel family. Four genes encode at least six subunits, which combine to form a variety of homotrimers and heterotrimers. Of these, ASIC1a homotrimers and ASIC1a/2 heterotrimers are most widely expressed in the central nervous system (CNS). Investigations into the function of ASIC1a in the CNS have revealed a wealth of information, culminating in multiple contemporary reviews. The lesser-studied ASIC2 subunits are in need of examination. This review will focus on ASIC2 in health and disease, with discussions of its role in modulating ASIC function, synaptic targeting, cardiovascular responses, and pharmacology, while exploring evidence of its influence in pathologies such as ischemic brain injury, multiple sclerosis, epilepsy, migraines, drug addiction, etc. This information substantiates the ASIC2 protein as a potential therapeutic target for various neurological, psychological, and cerebrovascular diseases.
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Affiliation(s)
| | | | | | - Xiang-Ping Chu
- Correspondence: ; Tel.: +1-816-235-2248; Fax: +1-816-235-6517
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7
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Chen Z, Lin S, Xie T, Lin JM, Canessa CM. A flexible GAS belt responds to pore mutations changing the ion selectivity of proton-gated channels. J Gen Physiol 2022; 154:212811. [PMID: 34766968 PMCID: PMC8594623 DOI: 10.1085/jgp.202112978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 08/18/2021] [Accepted: 10/18/2021] [Indexed: 11/20/2022] Open
Abstract
Proton-gated ion channels conduct mainly Na+ to induce postsynaptic membrane depolarization. Finding the determinants of ion selectivity requires knowledge of the pore structure in the open conformation, but such information is not yet available. Here, the open conformation of the hASIC1a channel was computationally modeled, and functional effects of pore mutations were analyzed in light of the predicted structures. The open pore structure shows two constrictions of similar diameter formed by the backbone of the GAS belt and, right beneath it, by the side chains of H28 from the reentrant loop. Models of nonselective mutant channels, but not those that maintain ion selectivity, predict enlargement of the GAS belt, suggesting that this motif is quite flexible and that the loss of stabilizing interactions in the central pore leads to changes in size/shape of the belt. Our results are consistent with the "close-fit" mechanism governing selectivity of hASIC1a, wherein the backbone of the GAS substitutes at least part of the hydration shell of a permeant ion to enable crossing the pore constriction.
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Affiliation(s)
- Zhuyuan Chen
- Department of Basic Sciences, Tsinghua University School of Medicine, Beijing, China
| | - Sheng Lin
- Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, China
| | - Tianze Xie
- Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, China
| | - Jin-Ming Lin
- Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, China
| | - Cecilia M Canessa
- Department of Basic Sciences, Tsinghua University School of Medicine, Beijing, China.,Cellular and Molecular Physiology, Yale University, New Haven, CT
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Qiao Q, Qu Z, Tian S, Cao H, Zhang Y, Sun C, Jia L, Wang W. Ketogenic Diet Alleviates Hippocampal Neurodegeneration Possibly via ASIC1a and the Mitochondria-Mediated Apoptotic Pathway in a Rat Model of Temporal Lobe Epilepsy. Neuropsychiatr Dis Treat 2022; 18:2181-2198. [PMID: 36187562 PMCID: PMC9521243 DOI: 10.2147/ndt.s376979] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 09/14/2022] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The ketogenic diet (KD) is a proven therapy for refractory epilepsy. Although the anti-seizure properties of this diet are understood to a certain extent, the exploration of its neuroprotective effects and underlying mechanisms is still in its infancy. Tissue acidosis is a common feature of epileptogenic foci. Interestingly, the activation of acid-sensing ion channel 1a (ASIC1a), which mediates Ca2+-dependent neuronal injury during acidosis, has been found to be inhibited by ketone bodies in vitro. This prompted us to investigate whether the neuroprotective effects induced by the KD occur via ASIC1a and interconnected downstream mechanisms in a rat model of temporal lobe epilepsy. METHODS Male Sprague-Dawley rats were fed either the KD or a normal diet for four weeks after undergoing pilocarpine-induced status epilepticus (SE). The effects of KD on epileptogenesis, cognitive impairment and hippocampal neuron injury in the epileptic rats were subsequently evaluated by video electroencephalogram, Morris water maze test and Nissl staining, respectively. The expression of ASIC1a and cleaved caspase-3 in the hippocampus were determined using Western blot analysis during the chronic period following SE. Moreover, the intracellular Ca2+ concentration, mitochondrial membrane potential (MMP), mitochondrial reactive oxygen species (mROS) and cell apoptosis of hippocampal cells were detected by flow cytometry. RESULTS We found that the KD treatment strongly attenuated the spontaneous recurrent seizures, ameliorated learning and memory impairments and prevented hippocampal neuronal injury and apoptosis. The KD was also shown to inhibit the upregulation of ASIC1a and the ensuing intracellular Ca2+ overload in the hippocampus of the epileptic rats. Furthermore, the seizure-induced structure disruption of neuronal mitochondria, loss of MMP and accumulation of mROS were reversed by the KD treatment, suggesting that it has protective effects on mitochondria. Finally, the activation of caspase-3 was also inhibited by the KD. CONCLUSION These findings indicate that the KD suppresses mitochondria-mediated apoptosis possibly by regulating ASIC1a to exert neuroprotective effects. This may provide a mechanistic explanation of the therapeutic effects of KD.
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Affiliation(s)
- Qi Qiao
- The Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, People's Republic of China
| | - Zhenzhen Qu
- The Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, People's Republic of China
| | - Shuang Tian
- The Department of Neurology, Shijiazhuang People's Hospital, Shijiazhuang, People's Republic of China
| | - Huifang Cao
- The Department of Rehabilitation, The Second Hospital of Hebei Medical University, Shijiazhuang, People's Republic of China
| | - Yange Zhang
- The Department of Pediatrics, The Second Hospital of Hebei Medical University, Shijiazhuang, People's Republic of China
| | - Can Sun
- The Department of Neurology, The Third Hospital of Peking University, Beijing, People's Republic of China
| | - Lijing Jia
- The Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, People's Republic of China
| | - Weiping Wang
- The Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, People's Republic of China
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9
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Foster VS, Rash LD, King GF, Rank MM. Acid-Sensing Ion Channels: Expression and Function in Resident and Infiltrating Immune Cells in the Central Nervous System. Front Cell Neurosci 2021; 15:738043. [PMID: 34602982 PMCID: PMC8484650 DOI: 10.3389/fncel.2021.738043] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 08/30/2021] [Indexed: 11/15/2022] Open
Abstract
Peripheral and central immune cells are critical for fighting disease, but they can also play a pivotal role in the onset and/or progression of a variety of neurological conditions that affect the central nervous system (CNS). Tissue acidosis is often present in CNS pathologies such as multiple sclerosis, epileptic seizures, and depression, and local pH is also reduced during periods of ischemia following stroke, traumatic brain injury, and spinal cord injury. These pathological increases in extracellular acidity can activate a class of proton-gated channels known as acid-sensing ion channels (ASICs). ASICs have been primarily studied due to their ubiquitous expression throughout the nervous system, but it is less well recognized that they are also found in various types of immune cells. In this review, we explore what is currently known about the expression of ASICs in both peripheral and CNS-resident immune cells, and how channel activation during pathological tissue acidosis may lead to altered immune cell function that in turn modulates inflammatory pathology in the CNS. We identify gaps in the literature where ASICs and immune cell function has not been characterized, such as neurotrauma. Knowledge of the contribution of ASICs to immune cell function in neuropathology will be critical for determining whether the therapeutic benefits of ASIC inhibition might be due in part to an effect on immune cells.
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Affiliation(s)
- Victoria S. Foster
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
| | - Lachlan D. Rash
- School of Biomedical Sciences, The University of Queensland, St Lucia, QLD, Australia
| | - Glenn F. King
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, St Lucia, QLD, Australia
| | - Michelle M. Rank
- Anatomy and Physiology, Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, VIC, Australia
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10
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Zhang YX, Qiao S, Cai MT, Lai QL, Shen CH, Ding MP. Association between autophagy-related protein 5 gene polymorphisms and epilepsy in Chinese patients. Neurosci Lett 2021; 753:135870. [PMID: 33812933 DOI: 10.1016/j.neulet.2021.135870] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 03/16/2021] [Accepted: 03/29/2021] [Indexed: 12/24/2022]
Abstract
Autophagy is a highly conserved degradative process that has been associated with a number of neurological diseases. Autophagy-related protein 5 (ATG5) is one of the key genes for the regulation of the autophagy pathway. In this study, we investigated the potential relationship between ATG5 gene polymorphisms and epilepsy in Han Chinese population. We enrolled 112 patients with epilepsy and 100 healthy controls and detected the genotypic and allelic data of 6 single nucleotide polymorphisms (SNPs) in ATG5 (rs2245214, rs510432, rs548234, rs573775, rs6568431 and rs6937876). The associations of 6 SNPs and epilepsy were evaluated. The results revealed the genotypes of overdominant of rs510432 between controls and patients showed significant differences (Poverdominant = 0.003). Subgroup analysis showed a highly significant association of rs510432 with late-onset epilepsy (Poverdominant = 0.006), and rs548234 were associated with the susceptibility to temporal lobe epilepsy (Pcodominant = 0.002, Poverdominant = 0.006). Furthermore, ATG5 was not linked to either early-onset epilepsy or drug-resistant epilepsy (p > 0.0083). These results demonstrated an association of an ATG5 gene variant with epilepsy, and stronger associations with several subgroups of epilepsy were identified. Our study may provide novel evidence for the role of ATG5 in epilepsy, and contribute to our understanding of the molecular mechanisms of this chronic neurological disease.
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Affiliation(s)
- Yin-Xi Zhang
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Song Qiao
- Department of Neurology, Zhejiang Hospital, Hangzhou, China
| | - Meng-Ting Cai
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Qi-Lun Lai
- Department of Neurology, Zhejiang Hospital, Hangzhou, China
| | - Chun-Hong Shen
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Mei-Ping Ding
- Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
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11
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Singh S, Singh TG, Rehni AK, Sharma V, Singh M, Kaur R. Reviving mitochondrial bioenergetics: A relevant approach in epilepsy. Mitochondrion 2021; 58:213-226. [PMID: 33775871 DOI: 10.1016/j.mito.2021.03.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 03/03/2021] [Accepted: 03/22/2021] [Indexed: 02/06/2023]
Abstract
Epileptogenesis is most commonly associated with neurodegeneration and a bioenergetic defect attributing to the fact that mitochondrial dysfunction plays a key precursor for neuronal death. Mitochondria are the essential organelle of neuronal cells necessary for certain neurophysiological processes like neuronal action potential activity and synaptic transmission. The mitochondrial dysfunction disrupts calcium homeostasis leading to inhibitory interneuron dysfunction and increasing the excitatory postsynaptic potential. In epilepsy, the prolonged repetitive neuronal activity increases the excessive demand for energy and acidosis in the brain further increasing the intracellular calcium causing neuronal death. Similarly, the mitochondrial damage also leads to the decline of energy by dysfunction of the electron transport chain and abnormal production of the ROS triggering the apoptotic neuronal death. Thus, the elevated level of cytosolic calcium causes the mitochondria DNA damage coinciding with mtROS and releasing the cytochrome c binding to Apaf protein further initiating the apoptosis resulting in epileptic encephalopathies. The various genetic and mRNA studies of epilepsy have explored the various pathogenic mutations of genes affecting the mitochondria functioning further initiating the neuronal excitotoxicity. Based on the results of previous studies, the recent therapeutic approaches are targeting basic mitochondrial processes, such as energy metabolism or free-radical generation, or specific interactions of disease-related proteins with mitochondria and hold great promise to attenuate epileptogenesis. Therefore, the current review emphasizes the emerging insights to uncover the relation between mitochondrial dysfunction and ROS generation contributing to mechanisms underlying epileptic seizures.
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Affiliation(s)
- Shareen Singh
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | | | - Ashish Kumar Rehni
- Cerebral Vascular Disease Research Laboratories, Department of Neurology and Neuroscience Program, University of Miami School of Medicine, Miami, FL 33101, USA
| | - Vivek Sharma
- Chitkara College of Pharmacy, Chitkara University, Punjab, India; Govt. College of Pharmacy, Rohru, District Shimla, Himachal Pradesh, 171207, India
| | - Manjinder Singh
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Rupinder Kaur
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
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12
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Thakran S, Guin D, Singh P, Singh P, Kukal S, Rawat C, Yadav S, Kushwaha SS, Srivastava AK, Hasija Y, Saso L, Ramachandran S, Kukreti R. Genetic Landscape of Common Epilepsies: Advancing towards Precision in Treatment. Int J Mol Sci 2020; 21:E7784. [PMID: 33096746 PMCID: PMC7589654 DOI: 10.3390/ijms21207784] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/09/2020] [Accepted: 10/14/2020] [Indexed: 12/15/2022] Open
Abstract
Epilepsy, a neurological disease characterized by recurrent seizures, is highly heterogeneous in nature. Based on the prevalence, epilepsy is classified into two types: common and rare epilepsies. Common epilepsies affecting nearly 95% people with epilepsy, comprise generalized epilepsy which encompass idiopathic generalized epilepsy like childhood absence epilepsy, juvenile myoclonic epilepsy, juvenile absence epilepsy and epilepsy with generalized tonic-clonic seizure on awakening and focal epilepsy like temporal lobe epilepsy and cryptogenic focal epilepsy. In 70% of the epilepsy cases, genetic factors are responsible either as single genetic variant in rare epilepsies or multiple genetic variants acting along with different environmental factors as in common epilepsies. Genetic testing and precision treatment have been developed for a few rare epilepsies and is lacking for common epilepsies due to their complex nature of inheritance. Precision medicine for common epilepsies require a panoramic approach that incorporates polygenic background and other non-genetic factors like microbiome, diet, age at disease onset, optimal time for treatment and other lifestyle factors which influence seizure threshold. This review aims to comprehensively present a state-of-art review of all the genes and their genetic variants that are associated with all common epilepsy subtypes. It also encompasses the basis of these genes in the epileptogenesis. Here, we discussed the current status of the common epilepsy genetics and address the clinical application so far on evidence-based markers in prognosis, diagnosis, and treatment management. In addition, we assessed the diagnostic predictability of a few genetic markers used for disease risk prediction in individuals. A combination of deeper endo-phenotyping including pharmaco-response data, electro-clinical imaging, and other clinical measurements along with genetics may be used to diagnose common epilepsies and this marks a step ahead in precision medicine in common epilepsies management.
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Affiliation(s)
- Sarita Thakran
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; (S.T.); (D.G.); (P.S.); (P.S.); (S.K.); (C.R.); (S.Y.)
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India;
| | - Debleena Guin
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; (S.T.); (D.G.); (P.S.); (P.S.); (S.K.); (C.R.); (S.Y.)
- Department of Bioinformatics, Delhi Technological University, Shahbad Daulatpur, Main Bawana Road, Delhi 110042, India;
| | - Pooja Singh
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; (S.T.); (D.G.); (P.S.); (P.S.); (S.K.); (C.R.); (S.Y.)
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India;
| | - Priyanka Singh
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; (S.T.); (D.G.); (P.S.); (P.S.); (S.K.); (C.R.); (S.Y.)
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India;
| | - Samiksha Kukal
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; (S.T.); (D.G.); (P.S.); (P.S.); (S.K.); (C.R.); (S.Y.)
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India;
| | - Chitra Rawat
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; (S.T.); (D.G.); (P.S.); (P.S.); (S.K.); (C.R.); (S.Y.)
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India;
| | - Saroj Yadav
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; (S.T.); (D.G.); (P.S.); (P.S.); (S.K.); (C.R.); (S.Y.)
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India;
| | - Suman S. Kushwaha
- Department of Neurology, Institute of Human Behaviour and Allied Sciences, Dilshad Garden, Delhi 110095, India;
| | - Achal K. Srivastava
- Department of Neurology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India;
| | - Yasha Hasija
- Department of Bioinformatics, Delhi Technological University, Shahbad Daulatpur, Main Bawana Road, Delhi 110042, India;
| | - Luciano Saso
- Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, P. le Aldo Moro 5, 00185 Rome, Italy;
| | - Srinivasan Ramachandran
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India;
- G N Ramachandran Knowledge Centre, Council of Scientific and Industrial Research (CSIR)—Institute of Genomics and Integrative Biology (IGIB), New Delhi 110007, India
| | - Ritushree Kukreti
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; (S.T.); (D.G.); (P.S.); (P.S.); (S.K.); (C.R.); (S.Y.)
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India;
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13
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A molecular view of the function and pharmacology of acid-sensing ion channels. Pharmacol Res 2020; 154:104166. [DOI: 10.1016/j.phrs.2019.02.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 02/01/2019] [Accepted: 02/02/2019] [Indexed: 02/06/2023]
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14
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Alijevic O, Bignucolo O, Hichri E, Peng Z, Kucera JP, Kellenberger S. Slowing of the Time Course of Acidification Decreases the Acid-Sensing Ion Channel 1a Current Amplitude and Modulates Action Potential Firing in Neurons. Front Cell Neurosci 2020; 14:41. [PMID: 32180707 PMCID: PMC7059123 DOI: 10.3389/fncel.2020.00041] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 02/12/2020] [Indexed: 12/14/2022] Open
Abstract
Acid-sensing ion channels (ASICs) are H+-activated neuronal Na+ channels. They are involved in fear behavior, learning, neurodegeneration after ischemic stroke and in pain sensation. ASIC activation has so far been studied only with fast pH changes, although the pH changes associated with many roles of ASICs are slow. It is currently not known whether slow pH changes can open ASICs at all. Here, we investigated to which extent slow pH changes can activate ASIC1a channels and induce action potential signaling. To this end, ASIC1a current amplitudes and charge transport in transfected Chinese hamster ovary cells, and ASIC-mediated action potential signaling in cultured cortical neurons were measured in response to defined pH ramps of 1-40 s duration from pH 7.4 to pH 6.6 or 6.0. A kinetic model of the ASIC1a current was developed and integrated into the Hodgkin-Huxley action potential model. Interestingly, whereas the ASIC1a current amplitude decreased with slower pH ramps, action potential firing was higher upon intermediate than fast acidification in cortical neurons. Indeed, fast pH changes (<4 s) induced short action potential bursts, while pH changes of intermediate speed (4-10 s) induced longer bursts. Slower pH changes (>10 s) did in many experiments not generate action potentials. Computer simulations corroborated these observations. We provide here the first description of ASIC function in response to defined slow pH changes. Our study shows that ASIC1a currents, and neuronal activity induced by ASIC1a currents, strongly depend on the speed of pH changes. Importantly, with pH changes that take >10 s to complete, ASIC1a activation is inefficient. Therefore, it is likely that currently unknown modulatory mechanisms allow ASIC activity in situations such as ischemia and inflammation.
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Affiliation(s)
- Omar Alijevic
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Olivier Bignucolo
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland.,SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Echrak Hichri
- Department of Physiology, University of Bern, Bern, Switzerland
| | - Zhong Peng
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Jan P Kucera
- Department of Physiology, University of Bern, Bern, Switzerland
| | - Stephan Kellenberger
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
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15
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Mango D, Nisticò R. Role of ASIC1a in Normal and Pathological Synaptic Plasticity. Rev Physiol Biochem Pharmacol 2020; 177:83-100. [PMID: 32789788 DOI: 10.1007/112_2020_45] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Acid-sensing ion channels (ASICs), members of the degenerin/epithelial Na+ channel superfamily, are broadly distributed in the mammalian nervous system where they play important roles in a variety of physiological processes, including neurotransmission and memory-related behaviors. In the last few years, we and others have investigated the role of ASIC1a in different forms of synaptic plasticity especially in the CA1 area of the hippocampus. This review summarizes the latest research linking ASIC1a to synaptic function either in physiological or pathological conditions. A better understanding of how these channels are regulated in brain circuitries relevant to synaptic plasticity and memory may offer novel targets for pharmacological intervention in neuropsychiatric and neurological disorders.
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Affiliation(s)
- Dalila Mango
- Laboratory of Pharmacology of Synaptic Plasticity, EBRI Rita Levi-Montalcini Foundation, Rome, Italy.
| | - Robert Nisticò
- Laboratory of Pharmacology of Synaptic Plasticity, EBRI Rita Levi-Montalcini Foundation, Rome, Italy
- School of Pharmacy, University of Rome Tor Vergata, Rome, Italy
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16
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Abstract
Degenerin/Epithelial Sodium Channels (DEG/ENaCs) are a large family of animal-specific non-voltage gated ion channels, with enriched expression in neuronal and epithelial tissues. While neuronal DEG/ENaCs were originally characterized as sensory receptor channels, recent studies indicate that several DEG/ENaC family members are also expressed throughout the central nervous system. Human genome-wide association studies have linked DEG/ENaC-coding genes with several neurologic and psychiatric disorders, including epilepsy and panic disorder. In addition, studies in rodent models further indicate that DEG/ENaC activity in the brain contributes to many behaviors, including those related to anxiety and long-term memory. Although the exact neurophysiological functions of DEG/ENaCs remain mostly unknown, several key studies now suggest that multiple family members might exert their neuronal function via the direct modulation of synaptic processes. Here, we review and discuss recent findings on the synaptic functions of DEG/ENaCs in both vertebrate and invertebrate species, and propose models for their possible roles in synaptic physiology.
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Affiliation(s)
- Alexis S Hill
- a Department of Biology , Washington University in St. Louis , St. Louis , USA
| | - Yehuda Ben-Shahar
- a Department of Biology , Washington University in St. Louis , St. Louis , USA
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17
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Abstract
Acid-sensing ion channels (ASICs) are a family of ion channels, consisting of four members; ASIC1 to 4. These channels are sensitive to changes in pH and are expressed throughout the central and peripheral nervous systems-including brain, spinal cord, and sensory ganglia. They have been implicated in a number of neurological conditions such as stroke and cerebral ischemia, traumatic brain injury, and epilepsy, and more recently in migraine. Their expression within areas of interest in the brain in migraine, such as the hypothalamus and PAG, their demonstrated involvement in preclinical models of meningeal afferent signaling, and their role in cortical spreading depression (the electrophysiological correlate of migraine aura), has enhanced research interest into these channels as potential therapeutic targets in migraine. Migraine is a disorder with a paucity of both acute and preventive therapies available, in which at best 50% of patients respond to available medications, and these medications often have intolerable side effects. There is therefore a great need for therapeutic development for this disabling condition. This review will summarize the understanding of the structure and CNS expression of ASICs, the mechanisms for their potential role in nociception, recent work in migraine, and areas for future research and drug development.
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Affiliation(s)
- Nazia Karsan
- Headache Group, Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, Kings College London, Denmark Hill, London, SE5 9PJ, UK
| | - Eric B Gonzales
- TCU and UNTHSC School of Medicine (applicant for LCME accreditation), Department of Medical Education, 3500 Camp Bowie Blvd., Fort Worth, TX, 76107, USA
| | - Gregory Dussor
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road, BSB-14, Richardson, TX, 75080, USA.
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18
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Zhang H, Gao G, Zhang Y, Sun Y, Li H, Dong S, Ma W, Liu B, Wang W, Wu H, Zhang H. Glucose Deficiency Elevates Acid-Sensing Ion Channel 2a Expression and Increases Seizure Susceptibility in Temporal Lobe Epilepsy. Sci Rep 2017; 7:5870. [PMID: 28725010 PMCID: PMC5517604 DOI: 10.1038/s41598-017-05038-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 05/24/2017] [Indexed: 01/09/2023] Open
Abstract
Brain hypometabolism is a common epilepsy-related finding in both patients and animal models. Fluorodeoxyglucose positron emission tomography studies have shown that recurrent seizures lead to reduced glucose metabolism in certain brain regions, but no studies have definitively determined whether this induces epileptogenesis. There is evidence that acid-sensing ion channel 2a (ASIC2a) affects epilepsy susceptibility. Transcription factor CP2 (TFCP2) regulates ASIC2a expression. We report that suppressed TFCP2 expression and elevated ASIC2a expression were associated with glucose hypometabolism in the hippocampi of humans with epilepsy and of rat epilepsy model brains. In cultured PC12 cells, we determined that glucose deficiency led to TFCP2 downregulating ASIC2a. Moreover, electrophysiological recordings from cultured rat hippocampal slices showed that ASIC2a overexpression resulted in more action potentials in CA1 pyramidal neurons and increased seizure susceptibility. Our findings suggest that hippocampal glucose hypometabolism elevates ASIC2a expression by suppressing TFCP2 expression, which further enhances the intrinsic excitability of CA1 pyramidal neurons and increases seizure susceptibility in patients with temporal lobe epilepsy.
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Affiliation(s)
- Haitao Zhang
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Guodong Gao
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Yu Zhang
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Yang Sun
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Huanfa Li
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Shan Dong
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Wei Ma
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Bei Liu
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Weiwen Wang
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Hao Wu
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China.
| | - Hua Zhang
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China.
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Pitkänen A, Löscher W, Vezzani A, Becker AJ, Simonato M, Lukasiuk K, Gröhn O, Bankstahl JP, Friedman A, Aronica E, Gorter JA, Ravizza T, Sisodiya SM, Kokaia M, Beck H. Advances in the development of biomarkers for epilepsy. Lancet Neurol 2017; 15:843-856. [PMID: 27302363 DOI: 10.1016/s1474-4422(16)00112-5] [Citation(s) in RCA: 229] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 02/16/2016] [Accepted: 03/02/2016] [Indexed: 12/13/2022]
Abstract
Over 50 million people worldwide have epilepsy. In nearly 30% of these cases, epilepsy remains unsatisfactorily controlled despite the availability of over 20 antiepileptic drugs. Moreover, no treatments exist to prevent the development of epilepsy in those at risk, despite an increasing understanding of the underlying molecular and cellular pathways. One of the major factors that have impeded rapid progress in these areas is the complex and multifactorial nature of epilepsy, and its heterogeneity. Therefore, the vision of developing targeted treatments for epilepsy relies upon the development of biomarkers that allow individually tailored treatment. Biomarkers for epilepsy typically fall into two broad categories: diagnostic biomarkers, which provide information on the clinical status of, and potentially the sensitivity to, specific treatments, and prognostic biomarkers, which allow prediction of future clinical features, such as the speed of progression, severity of epilepsy, development of comorbidities, or prediction of remission or cure. Prognostic biomarkers are of particular importance because they could be used to identify which patients will develop epilepsy and which might benefit from preventive treatments. Biomarker research faces several challenges; however, biomarkers could substantially improve the management of people with epilepsy and could lead to prevention in the right person at the right time, rather than just symptomatic treatment.
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Affiliation(s)
- Asla Pitkänen
- Department of Neurobiology, A I Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine, Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Annamaria Vezzani
- Department of Neuroscience, Experimental Neurology, IRCCS-Istituto di Recerche Farmacologiche "Mario Negri", Milan, Italy
| | - Albert J Becker
- Section for Translational Epilepsy Research, Department of Neuropathology, University of Bonn Medical Center, University of Bonn, Bonn, Germany
| | - Michele Simonato
- Department of Medical Sciences, Section of Pharmacology, University of Ferrara, Ferrara, Italy; Unit of Gene Therapy of Neurodegenerative Diseases, Division of Neuroscience, University Vita-Salute San Raffaele, Milan, Italy
| | - Katarzyna Lukasiuk
- The Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Olli Gröhn
- Department of Neurobiology, A I Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jens P Bankstahl
- Preclinical Molecular Imaging, Department of Nuclear Medicine, Hannover Medical School, Hannover, Germany
| | - Alon Friedman
- Department of Brain and Cognitive Sciences, Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Israel; Department of Medical Neuroscience, Dalhousie University, Halifax, NS, Canada
| | - Eleonora Aronica
- Department of Neuropathology, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands; Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, Netherlands; Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, Netherlands
| | - Jan A Gorter
- Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, Netherlands
| | - Teresa Ravizza
- Department of Neuroscience, Experimental Neurology, IRCCS-Istituto di Recerche Farmacologiche "Mario Negri", Milan, Italy
| | - Sanjay M Sisodiya
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK; Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK
| | - Merab Kokaia
- Epilepsy Center, Experimental Epilepsy Group, Division of Neurology, Department of Clinical Sciences, Lund University Hospital, Lund, Sweden
| | - Heinz Beck
- Laboratory for Experimental Epileptology and Cognition Research, Department of Epileptology, University of Bonn, Bonn, Germany; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.
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20
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Radu BM, Banciu A, Banciu DD, Radu M. Acid-Sensing Ion Channels as Potential Pharmacological Targets in Peripheral and Central Nervous System Diseases. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2015; 103:137-67. [PMID: 26920689 DOI: 10.1016/bs.apcsb.2015.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Acid-sensing ion channels (ASICs) are widely expressed in the body and represent good sensors for detecting protons. The pH drop in the nervous system is equivalent to ischemia and acidosis, and ASICs are very good detectors in discriminating slight changes in acidity. ASICs are important pharmacological targets being involved in a variety of pathophysiological processes affecting both the peripheral nervous system (e.g., peripheral pain, diabetic neuropathy) and the central nervous system (e.g., stroke, epilepsy, migraine, anxiety, fear, depression, neurodegenerative diseases, etc.). This review discusses the role played by ASICs in different pathologies and the pharmacological agents acting on ASICs that might represent promising drugs. As the majority of above-mentioned pathologies involve not only neuronal dysfunctions but also microvascular alterations, in the next future, ASICs may be also considered as potential pharmacological targets at the vasculature level. Perspectives and limitations in the use of ASICs antagonists and modulators as pharmaceutical agents are also discussed.
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Affiliation(s)
- Beatrice Mihaela Radu
- Department of Neurological and Movement Sciences, Section of Anatomy and Histology, University of Verona, Verona, Italy; Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Adela Banciu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Daniel Dumitru Banciu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Mihai Radu
- Department of Neurological and Movement Sciences, Section of Anatomy and Histology, University of Verona, Verona, Italy; Department of Life and Environmental Physics, 'Horia Hulubei' National Institute for Physics and Nuclear Engineering, Magurele, Romania.
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21
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Baron A, Lingueglia E. Pharmacology of acid-sensing ion channels – Physiological and therapeutical perspectives. Neuropharmacology 2015; 94:19-35. [DOI: 10.1016/j.neuropharm.2015.01.005] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 12/15/2014] [Accepted: 01/07/2015] [Indexed: 12/29/2022]
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Dussor G. ASICs as therapeutic targets for migraine. Neuropharmacology 2015; 94:64-71. [PMID: 25582295 PMCID: PMC4458434 DOI: 10.1016/j.neuropharm.2014.12.015] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 11/26/2014] [Accepted: 12/04/2014] [Indexed: 01/05/2023]
Abstract
Migraine is the most common neurological disorder and one of the most common chronic pain conditions. Despite its prevalence, the pathophysiology leading to migraine is poorly understood and the identification of new therapeutic targets has been slow. Several processes are currently thought to contribute to migraine including altered activity in the hypothalamus, cortical-spreading depression (CSD), and afferent sensory input from the cranial meninges. Decreased extracellular pH and subsequent activation of acid-sensing ion channels (ASICs) may contribute to each of these processes and may thus play a role in migraine pathophysiology. Although few studies have directly examined a role of ASICs in migraine, studies directly examining a connection have generated promising results including efficacy of ASIC blockers in both preclinical migraine models and in human migraine patients. The purpose of this review is to discuss the pathophysiology thought to contribute to migraine and findings that implicate decreased pH and/or ASICs in these events, as well as propose issues to be resolved in future studies of ASICs and migraine. This article is part of the Special Issue entitled 'Acid-Sensing Ion Channels in the Nervous System'.
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Affiliation(s)
- Greg Dussor
- The University of Texas at Dallas, School of Behavioral and Brain Sciences, GR-41, 800 West Campbell Road, Richardson, TX, 75080, USA.
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Wu H, Wang C, Liu B, Li H, Zhang Y, Dong S, Gao G, Zhang H. Altered Expression Pattern of Acid-Sensing Ion Channel Isoforms in Piriform Cortex After Seizures. Mol Neurobiol 2015; 53:1782-1793. [PMID: 25744567 DOI: 10.1007/s12035-015-9130-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 02/22/2015] [Indexed: 12/24/2022]
Abstract
The piriform cortex (PC) is highly susceptible to chemical and electrical seizure induction. Epileptiform activity is associated with an acid shift in extracellular pH, suggesting that acid-sensing ion channels (ASICs) expressed by PC neurons may contribute to this enhanced epileptogenic potential. In epileptic rats and surgical samples from patients with medial temporal lobe epilepsy (TLE), PC layer II ASIC1a-immunopositive neurons appeared swollen with dendritic elongation, and there was loss of ASIC1a-positive neurons in layer III, consistent with enhanced vulnerability to TLE-induced plasticity and cell death. In rats, pilocarpine-induced seizures led to transient downregulation of ASIC1a and concomitant upregulation of ASIC2a in the first few days post-seizure. These changes in expression may be due to seizure-induced oxidative stress as a similar reciprocal change in ASIC1a, and ASIC2a expression was observed in PC12 cells following H2O2 application. The proportion of ASIC1a/ASIC2a heteromers was reduced in the acute phase following status epilepticus (SE) but increased during the latent phase when rats developed spontaneous seizures. Knockdown of ASIC2a by RNAi reduced dendritic length and spine density in primary neurons, suggesting that seizure-induced upregulation of ASIC2a contributes to dendritic lengthening in PC layer II in rats. Administration of the ASIC inhibitor amiloride before pilocarpine reduced the proportion of rats reaching Racine level IV seizures, protected layer II and III neurons, and prolonged survival in the acute phase following SE. Our findings suggest that ASICs may enhance susceptibility to epileptogenesis in the PC. Inhibition of ASICs, particularly ASIC2a, may suppress seizures originating in the PC.
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Affiliation(s)
- Hao Wu
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xin-si Road, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Chao Wang
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xin-si Road, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Bei Liu
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xin-si Road, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Huanfa Li
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xin-si Road, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Yu Zhang
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xin-si Road, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Shan Dong
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xin-si Road, Xi'an, Shaanxi, 710038, People's Republic of China
| | - Guodong Gao
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xin-si Road, Xi'an, Shaanxi, 710038, People's Republic of China.
| | - Hua Zhang
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xin-si Road, Xi'an, Shaanxi, 710038, People's Republic of China.
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Vig PJS, Hearst SM, Shao Q, Lopez ME. Knockdown of acid-sensing ion channel 1a (ASIC1a) suppresses disease phenotype in SCA1 mouse model. THE CEREBELLUM 2015; 13:479-90. [PMID: 24788087 DOI: 10.1007/s12311-014-0563-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The mutated ataxin-1 protein in spinocerebellar ataxia 1 (SCA1) targets Purkinje cells (PCs) of the cerebellum and causes progressive ataxia due to loss of PCs and neurons of the brainstem. The exact mechanism of this cellular loss is still not clear. Currently, there are no treatments for SCA1; however, understanding of the mechanisms that regulate SCA1 pathology is essential for devising new therapies for SCA1 patients. We previously established a connection between the loss of intracellular calcium-buffering and calcium-signalling proteins with initiation of neurodegeneration in SCA1 transgenic (Tg) mice. Recently, acid-sensing ion channel 1a (ASIC1a) have been implicated in calcium-mediated toxicity in many brain disorders. Here, we report generating SCA1 Tg mice in the ASIC1a knockout (KO) background and demonstrate that the deletion of ASIC1a gene expression causes suppression of the SCA1 disease phenotype. Loss of the ASIC1a channel in SCA1/ASIC1a KO mice resulted in the improvement of motor deficit and decreased PC degeneration. Interestingly, the expression of the ASIC1 variant, ASIC1b, was upregulated in the cerebellum of both SCA1/ASIC1a KO and ASIC1a KO animals as compared to the wild-type (WT) and SCA1 Tg mice. Further, these SCA1/ASIC1a KO mice exhibited translocation of PC calcium-binding protein calbindin-D28k from the nucleus to the cytosol in young animals, which otherwise have both cytosolic and nuclear localization. Furthermore, in addition to higher expression of calcium-buffering protein parvalbumin, PCs of the older SCA1/ASIC1a KO mice showed a decrease in morphologic abnormalities as compared to the age-matched SCA1 animals. Our data suggest that ASIC1a may be a mediator of SCA1 pathogenesis and targeting ASIC1a could be a novel approach to treat SCA1.
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Affiliation(s)
- Parminder J S Vig
- Department of Neurology, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS, 39216, USA,
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Kellenberger S, Schild L. International Union of Basic and Clinical Pharmacology. XCI. Structure, Function, and Pharmacology of Acid-Sensing Ion Channels and the Epithelial Na+ Channel. Pharmacol Rev 2014; 67:1-35. [DOI: 10.1124/pr.114.009225] [Citation(s) in RCA: 193] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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Waszkielewicz AM, Gunia A, Szkaradek N, Słoczyńska K, Krupińska S, Marona H. Ion channels as drug targets in central nervous system disorders. Curr Med Chem 2013; 20:1241-85. [PMID: 23409712 PMCID: PMC3706965 DOI: 10.2174/0929867311320100005] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Revised: 01/14/2013] [Accepted: 01/18/2013] [Indexed: 12/27/2022]
Abstract
Ion channel targeted drugs have always been related with either the central nervous system (CNS), the peripheral nervous system, or the cardiovascular system. Within the CNS, basic indications of drugs are: sleep disorders, anxiety, epilepsy, pain, etc. However, traditional channel blockers have multiple adverse events, mainly due to low specificity of mechanism of action. Lately, novel ion channel subtypes have been discovered, which gives premises to drug discovery process led towards specific channel subtypes. An example is Na(+) channels, whose subtypes 1.3 and 1.7-1.9 are responsible for pain, and 1.1 and 1.2 - for epilepsy. Moreover, new drug candidates have been recognized. This review is focusing on ion channels subtypes, which play a significant role in current drug discovery and development process. The knowledge on channel subtypes has developed rapidly, giving new nomenclatures of ion channels. For example, Ca(2+)s channels are not any more divided to T, L, N, P/Q, and R, but they are described as Ca(v)1.1-Ca(v)3.3, with even newer nomenclature α1A-α1I and α1S. Moreover, new channels such as P2X1-P2X7, as well as TRPA1-TRPV1 have been discovered, giving premises for new types of analgesic drugs.
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Affiliation(s)
- A M Waszkielewicz
- Department of Bioorganic Chemistry, Chair of Organic Chemistry, Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Krakow, Poland.
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Abstract
Why do neurons sense extracellular acid? In large part, this question has driven increasing investigation on acid-sensing ion channels (ASICs) in the CNS and the peripheral nervous system for the past two decades. Significant progress has been made in understanding the structure and function of ASICs at the molecular level. Studies aimed at clarifying their physiological importance have suggested roles for ASICs in pain, neurological and psychiatric disease. This Review highlights recent findings linking these channels to physiology and disease. In addition, it discusses some of the implications for therapy and points out questions that remain unanswered.
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Leng TD, Xiong ZG. The pharmacology and therapeutic potential of small molecule inhibitors of acid-sensing ion channels in stroke intervention. Acta Pharmacol Sin 2013; 34:33-8. [PMID: 22820909 DOI: 10.1038/aps.2012.81] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
In the nervous system, a decrease in extracellular pH is a common feature of various physiological and pathological processes, including synaptic transmission, cerebral ischemia, epilepsy, brain trauma, and tissue inflammation. Acid-sensing ion channels (ASICs) are proton-gated cation channels that are distributed throughout the central and peripheral nervous systems. Following the recent identification of ASICs as critical acid-sensing extracellular proton receptors, growing evidence has suggested that the activation of ASICs plays important roles in physiological processes such as nociception, mechanosensation, synaptic plasticity, learning and memory. However, the over-activation of ASICs is also linked to adverse outcomes for certain pathological processes, such as brain ischemia and multiple sclerosis. Based on the well-demonstrated role of ASIC1a activation in acidosis-mediated brain injury, small molecule inhibitors of ASIC1a may represent novel therapeutic agents for the treatment of neurological disorders, such as stroke.
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Xiong QJ, Hu ZL, Wu PF, Ni L, Deng ZF, Wu WN, Chen JG, Wang F. Acid-sensing ion channels contribute to the increase in vesicular release from SH-SY5Y cells stimulated by extracellular protons. Am J Physiol Cell Physiol 2012; 303:C376-84. [PMID: 22592406 DOI: 10.1152/ajpcell.00067.2012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Acid-sensing ion channels (ASICs) have been reported to play a role in the neuronal dopamine pathway, but the exact role in neurotransmitter release remains elusive. Human neuroblastoma SH-SY5Y is a dopaminergic neuronal cell line, which can release monoamine neurotransmitters. In this study, the expression of ASICs was identified in SH-SY5Y cells to further explore the role of ASICs in vesicular release stimulated by acid. We gathered evidence that ASICs could be detected in SH-SY5Y cells. In whole cell patch-clamp recording, a rapid decrease in extracellular pH evoked inward currents, which were reversibly inhibited by 100 μM amiloride. The currents were pH dependent, with a pH of half-maximal activation (pH(0.5)) of 6.01 ± 0.04. Furthermore, in calcium imaging and FM 1-43 dye labeling, it was shown that extracellular protons increased intracellular calcium levels and vesicular release in SH-SY5Y cells, which was attenuated by PcTx1 and amiloride. Interestingly, N-type calcium channel blockers inhibited the vesicular release induced by acidification. In conclusion, ASICs are functionally expressed in SH-SY5Y cells and involved in vesicular release stimulated by acidification. N-type calcium channels may be involved in the increase in vesicular release induced by acid. Our results provide a preliminary study on ASICs in SH-SY5Y cells and neurotransmitter release, which helps to further investigate the relationship between ASICs and dopaminergic neurons.
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Affiliation(s)
- Qiu-Ju Xiong
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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