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Anselmi L, Ducrocq GP, Kim JS, Herold PB, Ruiz-Velasco V, Kaufman MP. Paradoxical potentiation of the exercise pressor reflex by endomorphin 2 in the presence of naloxone. J Appl Physiol (1985) 2024; 136:1097-1104. [PMID: 38511209 DOI: 10.1152/japplphysiol.00092.2024] [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: 02/01/2024] [Revised: 03/13/2024] [Accepted: 03/13/2024] [Indexed: 03/22/2024] Open
Abstract
When contracting muscles are freely perfused, the acid-sensing ion channel 3 (ASIC3) on group IV afferents plays a minor role in evoking the exercise pressor reflex. We recently showed in isolated dorsal root ganglion neurons innervating the gastrocnemius muscles that two mu opioid receptor agonists, namely endomorphin 2 and oxycodone, potentiated the sustained inward ASIC3 current evoked by acidic solutions. This in vitro finding prompted us to determine whether endomorphin 2 and oxycodone, when infused into the arterial supply of freely perfused contracting hindlimb muscles, potentiated the exercise pressor reflex. We found that infusion of endomorphin 2 and naloxone in decerebrated rats potentiated the pressor responses to contraction of the triceps surae muscles. The endomorphin 2-induced potentiation of the pressor responses to contraction was prevented by infusion of APETx2, an ASIC3 antagonist. Specifically, the peak pressor response to contraction averaged 19.3 ± 5.6 mmHg for control (n = 10), 27.2 ± 8.1 mmHg after naloxone and endomorphin 2 infusion (n = 10), and 20 ± 8 mmHg after APETx2 and endomorphin 2 infusion (n = 10). Infusion of endomorphin 2 and naloxone did not potentiate the pressor responses to contraction in ASIC3 knockout rats (n = 6). Partly similar findings were observed when oxycodone was substituted for endomorphin 2. Oxycodone infusion significantly increased the exercise pressor reflex over its control level, but subsequent APETx2 infusion failed to restore the increase to its control level (n = 9). The peak pressor response averaged 23.1 ± 8.6 mmHg for control (n = 9), 33.2 ± 11 mmHg after naloxone and oxycodone were infused (n = 9), and 27 ± 8.6 mmHg after APETx2 and oxycodone were infused (n = 9). Our data suggest that after opioid receptor blockade, ASIC3 stimulation by the endogenous mu opioid, endomorphin 2, potentiated the exercise pressor reflex.NEW & NOTEWORTHY This paper provides the first in vivo evidence that endomorphin 2, an endogenous opioid peptide, can paradoxically increase the magnitude of the exercise pressor reflex by an ASIC3-dependent mechanism even when the contracting muscles are freely perfused.
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Affiliation(s)
- Laura Anselmi
- Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania, United States
| | - Guillaume P Ducrocq
- Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania, United States
- Mitochondria, Oxidative Stress and Muscular Protection Laboratory (UR 3072), Faculty of Medicine, University of Strasbourg, Strasbourg, France
| | - Joyce S Kim
- Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania, United States
- Department of Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland, United States
| | - Paul B Herold
- Department of Anesthesiology and Perioperative Medicine, Penn State College of Medicine, Hershey, Pennsylvania, United States
| | - Victor Ruiz-Velasco
- Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania, United States
- Department of Anesthesiology and Perioperative Medicine, Penn State College of Medicine, Hershey, Pennsylvania, United States
| | - Marc P Kaufman
- Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania, United States
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Messina DN, Peralta ED, Acosta CG. Complex alterations in inflammatory pain and analgesic sensitivity in young and ageing female rats: involvement of ASIC3 and Nav1.8 in primary sensory neurons. Inflamm Res 2024; 73:669-691. [PMID: 38483556 DOI: 10.1007/s00011-024-01862-z] [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: 10/11/2023] [Revised: 02/05/2024] [Accepted: 02/12/2024] [Indexed: 04/10/2024] Open
Abstract
OBJECTIVE AND DESIGN Our aim was to determine an age-dependent role of Nav1.8 and ASIC3 in dorsal root ganglion (DRG) neurons in a rat pre-clinical model of long-term inflammatory pain. METHODS We compared 6 and 24 months-old female Wistar rats after cutaneous inflammation. We used behavioral pain assessments over time, qPCR, quantitative immunohistochemistry, selective pharmacological manipulation, ELISA and in vitro treatment with cytokines. RESULTS Older rats exhibited delayed recovery from mechanical allodynia and earlier onset of spontaneous pain than younger rats after inflammation. Moreover, the expression patterns of Nav1.8 and ASIC3 were time and age-dependent and ASIC3 levels remained elevated only in aged rats. In vivo, selective blockade of Nav1.8 with A803467 or of ASIC3 with APETx2 alleviated mechanical and cold allodynia and also spontaneous pain in both age groups with slightly different potency. Furthermore, in vitro IL-1β up-regulated Nav1.8 expression in DRG neurons cultured from young but not old rats. We also found that while TNF-α up-regulated ASIC3 expression in both age groups, IL-6 and IL-1β had this effect only on young and aged neurons, respectively. CONCLUSION Inflammation-associated mechanical allodynia and spontaneous pain in the elderly can be more effectively treated by inhibiting ASIC3 than Nav1.8.
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Affiliation(s)
- Diego N Messina
- Laboratory of Neurobiology of Pain, Faculty of Medical Sciences, IHEM (Instituto de Histologia y Embriologia Mendoza, Dr. Mario H Burgos), Cuyo National University, Av. Del Libertador 80, 5500, Mendoza, Argentina
| | - Emanuel D Peralta
- Laboratory of Neurobiology of Pain, Faculty of Medical Sciences, IHEM (Instituto de Histologia y Embriologia Mendoza, Dr. Mario H Burgos), Cuyo National University, Av. Del Libertador 80, 5500, Mendoza, Argentina
| | - Cristian G Acosta
- Laboratory of Neurobiology of Pain, Faculty of Medical Sciences, IHEM (Instituto de Histologia y Embriologia Mendoza, Dr. Mario H Burgos), Cuyo National University, Av. Del Libertador 80, 5500, Mendoza, Argentina.
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Guo Q, Fu J, Yuan L, Liao Y, Li M, Li X, Yi B, Zhang J, Gao B. Diversity analysis of sea anemone peptide toxins in different tissues of Heteractis crispa based on transcriptomics. Sci Rep 2024; 14:7684. [PMID: 38561372 PMCID: PMC10985097 DOI: 10.1038/s41598-024-58402-2] [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: 11/27/2023] [Accepted: 03/28/2024] [Indexed: 04/04/2024] Open
Abstract
Peptide toxins found in sea anemones venom have diverse properties that make them important research subjects in the fields of pharmacology, neuroscience and biotechnology. This study used high-throughput sequencing technology to systematically analyze the venom components of the tentacles, column, and mesenterial filaments of sea anemone Heteractis crispa, revealing the diversity and complexity of sea anemone toxins in different tissues. A total of 1049 transcripts were identified and categorized into 60 families, of which 91.0% were proteins and 9.0% were peptides. Of those 1049 transcripts, 416, 291, and 307 putative proteins and peptide precursors were identified from tentacles, column, and mesenterial filaments respectively, while 428 were identified when the datasets were combined. Of these putative toxin sequences, 42 were detected in all three tissues, including 33 proteins and 9 peptides, with the majority of peptides being ShKT domain, β-defensin, and Kunitz-type. In addition, this study applied bioinformatics approaches to predict the family classification, 3D structures, and functional annotation of these representative peptides, as well as the evolutionary relationships between peptides, laying the foundation for the next step of peptide pharmacological activity research.
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Affiliation(s)
- Qiqi Guo
- Engineering Research Center of Tropical Medicine Innovation and Transformation, Ministry of Education, International Joint Research Center of Human-machine Intelligent Collaborative for Tumor Precision Diagnosis and Treatment of Hainan Province, School of Pharmacy, Hainan Medical University, Haikou, China
| | - Jinxing Fu
- Engineering Research Center of Tropical Medicine Innovation and Transformation, Ministry of Education, International Joint Research Center of Human-machine Intelligent Collaborative for Tumor Precision Diagnosis and Treatment of Hainan Province, School of Pharmacy, Hainan Medical University, Haikou, China
| | - Lin Yuan
- Engineering Research Center of Tropical Medicine Innovation and Transformation, Ministry of Education, International Joint Research Center of Human-machine Intelligent Collaborative for Tumor Precision Diagnosis and Treatment of Hainan Province, School of Pharmacy, Hainan Medical University, Haikou, China
- Department of Pharmacy, 928th Hospital of PLA Joint Logistics Support Force, Haikou, China
| | - Yanling Liao
- Engineering Research Center of Tropical Medicine Innovation and Transformation, Ministry of Education, International Joint Research Center of Human-machine Intelligent Collaborative for Tumor Precision Diagnosis and Treatment of Hainan Province, School of Pharmacy, Hainan Medical University, Haikou, China
| | - Ming Li
- Engineering Research Center of Tropical Medicine Innovation and Transformation, Ministry of Education, International Joint Research Center of Human-machine Intelligent Collaborative for Tumor Precision Diagnosis and Treatment of Hainan Province, School of Pharmacy, Hainan Medical University, Haikou, China
| | - Xinzhong Li
- School of Health and Life Sciences, Teesside University, Middlesbrough, UK
| | - Bo Yi
- Department of Pharmacy, 928th Hospital of PLA Joint Logistics Support Force, Haikou, China
| | - Junqing Zhang
- Engineering Research Center of Tropical Medicine Innovation and Transformation, Ministry of Education, International Joint Research Center of Human-machine Intelligent Collaborative for Tumor Precision Diagnosis and Treatment of Hainan Province, School of Pharmacy, Hainan Medical University, Haikou, China.
| | - Bingmiao Gao
- Engineering Research Center of Tropical Medicine Innovation and Transformation, Ministry of Education, International Joint Research Center of Human-machine Intelligent Collaborative for Tumor Precision Diagnosis and Treatment of Hainan Province, School of Pharmacy, Hainan Medical University, Haikou, China.
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Atmani K, Meleine M, Langlois L, Coëffier M, Brumovsky P, Leroi AM, Gourcerol G. Involvement of acid sensing ion channel (ASIC)-3 in an acute urinary bladder-colon cross sensitization model in rodent. FRONTIERS IN PAIN RESEARCH 2023; 4:1083514. [PMID: 36969917 PMCID: PMC10030710 DOI: 10.3389/fpain.2023.1083514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 02/10/2023] [Indexed: 03/11/2023] Open
Abstract
IntroductionIrritable bowel syndrome and bladder pain syndrome are both characterized by pain in response to organ distension. Epidemiologic studies showed that these two syndromes are often overlapped. Such overlap may be due to sharing of common extrinsic innervations between the colorectum and the urinary bladder, where cross-sensitization of the urinary bladder and the colon would occur in response to mechanical distension of either organ. The aim of this project was to develop and characterize a rodent model of urinary bladder-colon sensitization and to assess the role of the acid sensing ion channel (ASIC)-3.MethodsDouble retrograde labelling was performed to identify extrinsic primary afferent neurons innervating both the colon (Fluororuby) and urinary bladder (Fluorogold) in the L6-S1 dorsal root ganglia (DRG) in Sprague Dawley rats. The phenotype of the colon/urinary bladder co-innervating primary afferent neurons was assessed using immunohistochemistry directed against ASIC-3. Cross-organ sensitization was induced in Sprague Dawley rats by using an echography-guided intravesical administration of acetic acid (0.75%) under brief isoflurane anesthesia. Colonic sensitivity was assessed in conscious rats by measuring abdominal contraction during isobaric colorectal distension (CRD). Measurement of urinary bladder and colonic paracellular permeabilities and tissue myeloperoxidase assay were performed. The involvement of ASIC-3 was assessed by use of S1 intrathecal administration of the ASIC-3 blocker, APETx2 (2.2 µM).ResultsImmunohistochemistry showed that 73.1% of extrinsic primary afferent neurons co-innervating the colon and the urinary bladder express ASIC-3. By contrast, extrinsic primary afferent neurons innervating the colon only or the urinary bladder only were positive for ASIC-3 in 39.3% and 42.6%, respectively. Echography-guided intravesical administration of acetic acid resulted in colonic hypersensitivity to colorectal distension. This effect started 1 h post-injection and lasted up to 24 h, and was not longer seen after 3 days after injection. No colonic hyperpermeability and no difference in urinary bladder and colon MPO activity was observed between control and acetic acid-treated rats. Colonic sensitization by intravesical acetic acid administration was prevented by S1 intrathecal administration of APETx2.ConclusionWe developed an acute pelvic cross-organ sensitization model in conscious rat. In this model, cross-organ sensitization is likely to involve S1-L6 extrinsic primary afferents co-innervating the colon and urinary bladder through an ASIC-3 pathway.
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Affiliation(s)
- Karim Atmani
- Nutrition, Gut & Brain Unit (INSERM U1073), Institute for Biomedical Research and Innovation, Rouen University, Rouen, France
| | - Mathieu Meleine
- Nutrition, Gut & Brain Unit (INSERM U1073), Institute for Biomedical Research and Innovation, Rouen University, Rouen, France
| | - Ludovic Langlois
- Nutrition, Gut & Brain Unit (INSERM U1073), Institute for Biomedical Research and Innovation, Rouen University, Rouen, France
| | - Moïse Coëffier
- Nutrition, Gut & Brain Unit (INSERM U1073), Institute for Biomedical Research and Innovation, Rouen University, Rouen, France
| | - Pablo Brumovsky
- Institute of Research in in Translational Medicine, CONICET-Austral University, Pilar, Argentina
| | - Anne-Marie Leroi
- Nutrition, Gut & Brain Unit (INSERM U1073), Institute for Biomedical Research and Innovation, Rouen University, Rouen, France
- Department of Physiology, Rouen University Hospital, Rouen, France
| | - Guillaume Gourcerol
- Nutrition, Gut & Brain Unit (INSERM U1073), Institute for Biomedical Research and Innovation, Rouen University, Rouen, France
- Department of Physiology, Rouen University Hospital, Rouen, France
- Correspondence: Guillaume Gourcerol
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Group II metabotropic glutamate receptor activation attenuates acid-sensing ion channel currents in rat primary sensory neurons. J Biol Chem 2023; 299:102953. [PMID: 36731795 PMCID: PMC9976456 DOI: 10.1016/j.jbc.2023.102953] [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: 09/21/2022] [Revised: 01/24/2023] [Accepted: 01/25/2023] [Indexed: 02/01/2023] Open
Abstract
Acid-sensing ion channels (ASICs) play an important role in pain associated with tissue acidification. Peripheral inhibitory group II metabotropic glutamate receptors (mGluRs) have analgesic effects in a variety of pain conditions. Whether there is a link between ASICs and mGluRs in pain processes is still unclear. Herein, we show that the group II mGluR agonist LY354740 inhibited acid-evoked ASIC currents and action potentials in rat dorsal root ganglia neurons. LY354740 reduced the maximum current response to protons, but it did not change the sensitivity of ASICs to protons. LY354740 inhibited ASIC currents by activating group II mGluRs. We found that the inhibitory effect of LY354740 was blocked by intracellular application of the Gi/o protein inhibitor pertussis toxin and the cAMP analogue 8-Br-cAMP and mimicked by the protein kinase A (PKA) inhibitor H-89. LY354740 also inhibited ASIC3 currents in CHO cells coexpressing mGluR2 and ASIC3 but not in cells expressing ASIC3 alone. In addition, intraplantar injection of LY354740 dose-dependently alleviated acid-induced nociceptive behavior in rats through local group II mGluRs. Together, these results suggested that activation of peripheral group II mGluRs inhibited the functional activity of ASICs through a mechanism that depended on Gi/o proteins and the intracellular cAMP/PKA signaling pathway in rat dorsal root ganglia neurons. We propose that peripheral group II mGluRs are an important therapeutic target for ASIC-mediated pain.
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Kaulich E, Grundy LJ, Schafer WR, Walker DS. The diverse functions of the DEG/ENaC family: linking genetic and physiological insights. J Physiol 2022; 601:1521-1542. [PMID: 36314992 PMCID: PMC10148893 DOI: 10.1113/jp283335] [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: 07/06/2022] [Accepted: 10/25/2022] [Indexed: 11/06/2022] Open
Abstract
The DEG/ENaC family of ion channels was defined based on the sequence similarity between degenerins (DEG) from the nematode Caenorhabditis elegans and subunits of the mammalian epithelial sodium channel (ENaC), and also includes a diverse array of non-voltage-gated cation channels from across animal phyla, including the mammalian acid-sensing ion channels (ASICs) and Drosophila pickpockets. ENaCs and ASICs have wide ranging medical importance; for example, ENaCs play an important role in respiratory and renal function, and ASICs in ischaemia and inflammatory pain, as well as being implicated in memory and learning. Electrophysiological approaches, both in vitro and in vivo, have played an essential role in establishing the physiological properties of this diverse family, identifying an array of modulators and implicating them in an extensive range of cellular functions, including mechanosensation, acid sensation and synaptic modulation. Likewise, genetic studies in both invertebrates and vertebrates have played an important role in linking our understanding of channel properties to function at the cellular and whole animal/behavioural level. Drawing together genetic and physiological evidence is essential to furthering our understanding of the precise cellular roles of DEG/ENaC channels, with the diversity among family members allowing comparative physiological studies to dissect the molecular basis of these diverse functions.
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Affiliation(s)
- Eva Kaulich
- Neurobiology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, UK
| | - Laura J Grundy
- Neurobiology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, UK
| | - William R Schafer
- Neurobiology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, UK.,Department of Biology, KU Leuven, Leuven, Belgium
| | - Denise S Walker
- Neurobiology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, UK
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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: 0] [Impact Index Per Article: 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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Jurczak A, Delay L, Barbier J, Simon N, Krock E, Sandor K, Agalave NM, Rudjito R, Wigerblad G, Rogóż K, Briat A, Miot-Noirault E, Martinez-Martinez A, Brömme D, Grönwall C, Malmström V, Klareskog L, Khoury S, Ferreira T, Labrum B, Deval E, Jiménez-Andrade JM, Marchand F, Svensson CI. Antibody-induced pain-like behavior and bone erosion: links to subclinical inflammation, osteoclast activity, and acid-sensing ion channel 3-dependent sensitization. Pain 2022; 163:1542-1559. [PMID: 34924556 PMCID: PMC9341234 DOI: 10.1097/j.pain.0000000000002543] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 09/28/2021] [Accepted: 09/30/2021] [Indexed: 11/27/2022]
Abstract
ABSTRACT Several bone conditions, eg, bone cancer, osteoporosis, and rheumatoid arthritis (RA), are associated with a risk of developing persistent pain. Increased osteoclast activity is often the hallmark of these bony pathologies and not only leads to bone remodeling but is also a source of pronociceptive factors that sensitize the bone-innervating nociceptors. Although historically bone loss in RA has been believed to be a consequence of inflammation, both bone erosion and pain can occur years before the symptom onset. Here, we have addressed the disconnection between inflammation, pain, and bone erosion by using a combination of 2 monoclonal antibodies isolated from B cells of patients with RA. We have found that mice injected with B02/B09 monoclonal antibodies (mAbs) developed a long-lasting mechanical hypersensitivity that was accompanied by bone erosion in the absence of joint edema or synovitis. Intriguingly, we have noted a lack of analgesic effect of naproxen and a moderate elevation of few inflammatory factors in the ankle joints suggesting that B02/B09-induced pain-like behavior does not depend on inflammatory processes. By contrast, we found that inhibiting osteoclast activity and acid-sensing ion channel 3 signaling prevented the development of B02/B09-mediated mechanical hypersensitivity. Moreover, we have identified secretory phospholipase A2 and lysophosphatidylcholine 16:0 as critical components of B02/B09-induced pain-like behavior and shown that treatment with a secretory phospholipase A2 inhibitor reversed B02/B09-induced mechanical hypersensitivity and bone erosion. Taken together, our study suggests a potential link between bone erosion and pain in a state of subclinical inflammation and offers a step forward in understanding the mechanisms of bone pain in diseases such as RA.
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Affiliation(s)
- Alexandra Jurczak
- Department of Physiology and Pharmacology, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Lauriane Delay
- Université Clermont Auvergne, Inserm U1107 Neuro-Dol, Pharmacologie Fondamentale et Clinique de la Douleur, Clermont-Ferrand, France
| | - Julie Barbier
- Université Clermont Auvergne, Inserm U1107 Neuro-Dol, Pharmacologie Fondamentale et Clinique de la Douleur, Clermont-Ferrand, France
| | - Nils Simon
- Department of Physiology and Pharmacology, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Emerson Krock
- Department of Physiology and Pharmacology, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Katalin Sandor
- Department of Physiology and Pharmacology, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Nilesh M. Agalave
- Department of Physiology and Pharmacology, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Resti Rudjito
- Department of Physiology and Pharmacology, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Gustaf Wigerblad
- Department of Physiology and Pharmacology, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Katarzyna Rogóż
- Department of Physiology and Pharmacology, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Arnaud Briat
- Université Clermont Auvergne, Inserm UMR 1240, IMoST, Imagerie Moléculaire et Stratégies Théranostiques, Clermont-Ferrand, France
| | - Elisabeth Miot-Noirault
- Université Clermont Auvergne, Inserm UMR 1240, IMoST, Imagerie Moléculaire et Stratégies Théranostiques, Clermont-Ferrand, France
| | - Arisai Martinez-Martinez
- Unidad Academica Multidisciplinaria Reynosa Aztlan, Universidad Autonoma de Tamaulipas, Reynosa, Tamaulipas, Mexico
| | - Dieter Brömme
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
| | - Caroline Grönwall
- Department of Medicine, Division of Rheumatology, Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Vivianne Malmström
- Department of Medicine, Division of Rheumatology, Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Lars Klareskog
- Department of Medicine, Division of Rheumatology, Center for Molecular Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Spiro Khoury
- Lipotoxicity and Channelopathies (LiTch)—ConicMeds, Université de Poitiers, Poitiers, France
| | - Thierry Ferreira
- Lipotoxicity and Channelopathies (LiTch)—ConicMeds, Université de Poitiers, Poitiers, France
| | - Bonnie Labrum
- Université Côte d’Azur, CNRS, IPMC, LabEx ICST, FHU InovPain, France
| | - Emmanuel Deval
- Université Côte d’Azur, CNRS, IPMC, LabEx ICST, FHU InovPain, France
| | - Juan Miguel Jiménez-Andrade
- Unidad Academica Multidisciplinaria Reynosa Aztlan, Universidad Autonoma de Tamaulipas, Reynosa, Tamaulipas, Mexico
| | - Fabien Marchand
- Université Clermont Auvergne, Inserm U1107 Neuro-Dol, Pharmacologie Fondamentale et Clinique de la Douleur, Clermont-Ferrand, France
| | - Camilla I. Svensson
- Department of Physiology and Pharmacology, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
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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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10
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Periodontal acidification contributes to tooth pain hypersensitivity during orthodontic tooth movement. Neurosci Res 2021; 177:103-110. [PMID: 34808249 DOI: 10.1016/j.neures.2021.11.007] [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: 10/20/2021] [Revised: 11/18/2021] [Accepted: 11/18/2021] [Indexed: 12/24/2022]
Abstract
Tooth movements associated with orthodontic treatment often cause tooth pain. However, the detailed mechanism remains unclear. Here, we examined the involvement of periodontal acidification caused by tooth movement in mechanical tooth pain hypersensitivity. Elastics were inserted between the first and second molars to move the teeth in Sprague-Dawley rats. Mechanical head-withdrawal reflex threshold to first molar stimulation and the pH of the gingival sulcus around the tooth were measured. The expression of acid-sensing ion channel 3 (ASIC3) in trigeminal ganglion neurons and phosphorylation of ASIC3 in the periodontal tissue were analyzed. The mechanical head-withdrawal reflex threshold to first molar stimulation and pH in the gingival sulcus decreased on day 1 after the elastic insertion. These decreases recovered to the sham level by buffering periodontal acidification. Periodontal inhibition of ASIC3 channel activity reversed the decreased mechanical head-withdrawal reflex threshold to first molar stimulation. On day 1 after elastic insertion, the tooth movement did not change the number of ASIC3 immunoreactive trigeminal ganglion neurons innervating the periodontal tissue but increased phosphorylated-ASIC3 levels in the periodontal tissue. Periodontal acidification induced by tooth movement causes phosphorylation of ASIC3, resulting in mechanical pain hypersensitivity in mechanically forced tooth.
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11
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Morgan M, Thai J, Trinh P, Habib M, Effendi KN, Ivanusic JJ. ASIC3 inhibition modulates inflammation-induced changes in the activity and sensitivity of Aδ and C fiber sensory neurons that innervate bone. Mol Pain 2021; 16:1744806920975950. [PMID: 33280501 PMCID: PMC7724402 DOI: 10.1177/1744806920975950] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The Acid Sensing Ion Channel 3 (ASIC3) is a non-selective cation channel that is
activated by acidification, and is known to have a role in regulating
inflammatory pain. It has pro-algesic roles in a range of conditions that
present with bone pain, but the mechanism for this has not yet been
demonstrated. We aimed to determine if ASIC3 is expressed in Aδ and/or C fiber
bone afferent neurons, and to explore its role in the activation and
sensitization of bone afferent neurons after acute inflammation. A combination
of retrograde tracing and immunohistochemistry was used to determine expression
of ASIC3 in the soma of bone afferent neurons. A novel, in
vivo, electrophysiological bone-nerve preparation was used to make
recordings of the activity and sensitivity of bone afferent neurons in the
presence of carrageenan-induced inflammation, with and without the selective
ASIC3 inhibitor APET×2. A substantial proportion of bone afferent neurons
express ASIC3, including unmyelinated (neurofilament poor) and small diameter
myelinated (neurofilament rich) neurons that are likely to be C and Aδ nerve
fibers respectively. Electrophysiological recordings revealed that application
of APET×2 to the marrow cavity inhibited carrageenan-induced spontaneous
activity of C and Aδ fiber bone afferent neurons. APET×2 also inhibited
carrageenan-induced sensitization of Aδ and C fiber bone afferent neurons to
mechanical stimulation, but had no effect on the sensitivity of bone afferent
neurons in the absence of inflammation. This evidence supports a role for ASIC3
in the pathogenesis of pain associated with inflammation of the bone.
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Affiliation(s)
- Michael Morgan
- Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, Victoria, Australia
| | - Jenny Thai
- Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, Victoria, Australia
| | - Phu Trinh
- Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, Victoria, Australia
| | - Mohamed Habib
- Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, Victoria, Australia
| | - Kelly N Effendi
- Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, Victoria, Australia
| | - Jason J Ivanusic
- Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, Victoria, Australia
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12
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Citric Acid in Drug Formulations Causes Pain by Potentiating Acid-Sensing Ion Channel 1. J Neurosci 2021; 41:4596-4606. [PMID: 33888605 PMCID: PMC8260239 DOI: 10.1523/jneurosci.2087-20.2021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 12/08/2020] [Accepted: 04/10/2021] [Indexed: 11/21/2022] Open
Abstract
Pain at the injection site is a common complaint of patients receiving therapeutic formulations containing citric acid. Despite the widely acknowledged role of acid-sensing ion channels (ASICs) in acid-related perception, the specific ASIC subtype mediating pain caused by subcutaneous acid injection and the mechanism by which citrate affects this process are less clear. Here, male mice subjected to intraplantar acid injection responded by executing a withdrawal reflex, and this response was abolished by ASIC1 but not ASIC2 knockout. Although intraplantar injection of neutral citrate solution did not produce this response, intraplantar injection of acidic citrate solution produced a withdrawal reflex greater than that produced by acidity alone. Consistent with the behavioral data, neutral citrate failed to produce an electrophysiological response in HEK293 cells, which express ASIC1, but acidic citrate produced a whole-cell inward current greater than that produced by acidity alone. Saturating the intracellular solution with citrate had no effect on the potentiating effect of extracellular citrate, suggesting that citrate acted extracellularly to potentiate ASIC1. Moreover, exposure to citrate immediately before acid stimulation failed to potentiate ASIC1 currents, which ruled out the involvement of a metabotropic receptor gated by a citrate metabolite. Finally, removal of calcium ions from the extracellular solution mimicked the potentiating effect of citrate and prevented citrate from further potentiating ASIC1. Our data demonstrate that ASIC1 is necessary for the nociceptive response caused by subcutaneous acid infusion and that neutral citrate, despite not inducing ASIC1 currents or nociceptive behavior on its own, potentiates acid nociception by removing the inhibitory effect of extracellular calcium ions on ASIC1. SIGNIFICANCE STATEMENT Citric acid is a common ingredient used in pharmaceutical formulations. Despite the widespread clinical use of these formulations, it remains unclear how citric acid causes pain when injected into patients. We identified ASIC1 as the key receptor used to detect injection-site pain caused by acid, and we showed that neutral citrate does not stimulate ASIC1; instead, citrate substantially potentiates ASIC1 activation when injected simultaneously with acid. In addition, we demonstrated that citrate potentiates ASIC1 by removing the inhibitory action of calcium on the extracellular side of the receptor. Given that injection-site pain is the primary complaint of patients receiving citrate-containing medical products, our data provide mechanistic insight into a common medical complaint and suggest a means of avoiding injection pain.
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Osmakov DI, Khasanov TA, Andreev YA, Lyukmanova EN, Kozlov SA. Animal, Herb, and Microbial Toxins for Structural and Pharmacological Study of Acid-Sensing Ion Channels. Front Pharmacol 2020; 11:991. [PMID: 32733241 PMCID: PMC7360831 DOI: 10.3389/fphar.2020.00991] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 06/19/2020] [Indexed: 12/22/2022] Open
Abstract
Acid-sensing ion channels (ASICs) are of the most sensitive molecular sensors of extracellular pH change in mammals. Six isoforms of these channels are widely represented in membranes of neuronal and non-neuronal cells, where these molecules are involved in different important regulatory functions, such as synaptic plasticity, learning, memory, and nociception, as well as in various pathological states. Structural and functional studies of both wild-type and mutant ASICs are essential for human care and medicine for the efficient treatment of socially significant diseases and ensure a comfortable standard of life. Ligands of ASICs serve as indispensable tools for these studies. Such bioactive compounds can be synthesized artificially. However, to date, the search for such molecules has been most effective amongst natural sources, such as animal venoms or plants and microbial extracts. In this review, we provide a detailed and comprehensive structural and functional description of natural compounds acting on ASICs, as well as the latest information on structural aspects of their interaction with the channels. Many of the examples provided in the review demonstrate the undoubted fundamental and practical successes of using natural toxins. Without toxins, it would not be possible to obtain data on the mechanisms of ASICs' functioning, provide detailed study of their pharmacological properties, or assess the contribution of the channels to development of different pathologies. The selectivity to different isoforms and variety in the channel modulation mode allow for the appraisal of prospective candidates for the development of new drugs.
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Affiliation(s)
- Dmitry I. Osmakov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia
| | - Timur A. Khasanov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
| | - Yaroslav A. Andreev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia
| | - Ekaterina N. Lyukmanova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
| | - Sergey A. Kozlov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
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14
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Kim JS, Ducrocq GP, Kaufman MP. Functional knockout of ASIC3 attenuates the exercise pressor reflex in decerebrated rats with ligated femoral arteries. Am J Physiol Heart Circ Physiol 2020; 318:H1316-H1324. [PMID: 32302492 PMCID: PMC7346538 DOI: 10.1152/ajpheart.00137.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/23/2020] [Accepted: 04/12/2020] [Indexed: 11/22/2022]
Abstract
The exercise pressor reflex arises from contracting muscle and is manifested by increases in arterial pressure, heart rate, and cardiac contractility. In patients with peripheral artery disease, the exercise pressor reflex is exaggerated. This effect is believed to be caused by a metabolite whose concentration is increased when the working muscles are inadequately perfused. Previous work in rats with simulated peripheral artery disease has shown that pharmacological blockade of acid-sensing ion channel 3 (ASIC3), which is found on group III and IV afferents, prevented the exaggeration of the exercise pressor reflex. Blockade of ASIC3, however, may have off-target effects that preclude a conclusion that ASIC3 plays a role in evoking the reflex in rats with simulated peripheral artery disease. In the present experiments performed in decerebrated rats with simulated peripheral artery disease, we compared the exercise pressor reflex in rats with a functional knockout of the ASIC3 (KO) with the reflex in their wild-type counterparts (WT). We found that the exercise pressor reflex in ASIC3 KO rats was significantly lower than the exercise pressor reflex in their WT counterparts (P < 0.05). ASIC 3 KO rats demonstrated lower pressor responses to intra-arterial injection of diprotonated phosphate (86 mM; pH 6.0), lactic acid (12 mM; pH 2.85), and capsaicin (0.2 μg; pH 7.2) (P < 0.05). In contrast, both ligated WT and ASIC3 KO rats displayed similar pressor responses to tendon stretch (P > 0.05). We conclude that ASIC3 play an important role in evoking the exaggerated exercise pressor reflex in rats with peripheral artery disease.NEW & NOTEWORTHY We used a genetic approach to test the hypothesis that the magnitude of the exercise pressor reflex evoked in ligated ASIC3 KO rats was significantly lower than the magnitude of the exercise pressor reflex evoked in their ligated wild-type (WT) counterparts. The pressor response to contraction in ligated ASIC3 KO rats was significantly smaller than was the pressor response to contraction in ligated WT rats.
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Affiliation(s)
- Joyce S Kim
- Heart and Vascular Institute and Department of Medicine, Penn State College of Medicine, Hershey, Pennsylvania
| | - Guillaume P Ducrocq
- Heart and Vascular Institute and Department of Medicine, Penn State College of Medicine, Hershey, Pennsylvania
| | - Marc P Kaufman
- Heart and Vascular Institute and Department of Medicine, Penn State College of Medicine, Hershey, Pennsylvania
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15
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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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16
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Callejo G, Pattison LA, Greenhalgh JC, Chakrabarti S, Andreopoulou E, Hockley JRF, Smith ESJ, Rahman T. In silico screening of GMQ-like compounds reveals guanabenz and sephin1 as new allosteric modulators of acid-sensing ion channel 3. Biochem Pharmacol 2020; 174:113834. [PMID: 32027884 PMCID: PMC7068650 DOI: 10.1016/j.bcp.2020.113834] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 01/31/2020] [Indexed: 11/25/2022]
Abstract
Acid-sensing ion channels (ASICs) are voltage-independent cation channels that detect decreases in extracellular pH. Dysregulation of ASICs underpins a number of pathologies. Of particular interest is ASIC3, which is recognised as a key sensor of acid-induced pain and is important in the establishment of pain arising from inflammatory conditions, such as rheumatoid arthritis. Thus, the identification of new ASIC3 modulators and the mechanistic understanding of how these compounds modulate ASIC3 could be important for the development of new strategies to counteract the detrimental effects of dysregulated ASIC3 activity in inflammation. Here, we report the identification of novel ASIC3 modulators based on the ASIC3 agonist, 2-guanidine-4-methylquinazoline (GMQ). Through a GMQ-guided in silico screening of Food and Drug administration (FDA)-approved drugs, 5 compounds were selected and tested for their modulation of rat ASIC3 (rASIC3) using whole-cell patch-clamp electrophysiology. Of the chosen drugs, guanabenz (GBZ), an α2-adrenoceptor agonist, produced similar effects to GMQ on rASIC3, activating the channel at physiological pH (pH 7.4) and potentiating its response to mild acidic (pH 7) stimuli. Sephin1, a GBZ derivative that lacks α2-adrenoceptor activity, has been proposed to act as a selective inhibitor of a regulatory subunit of the stress-induced protein phosphatase 1 (PPP1R15A) with promising therapeutic potential for the treatment of multiple sclerosis. However, we found that like GBZ, sephin1 activates rASIC3 at pH 7.4 and potentiates its response to acidic stimulation (pH 7), i.e. sephin1 is a novel modulator of rASIC3. Furthermore, docking experiments showed that, like GMQ, GBZ and sephin1 likely interact with the nonproton ligand sensor domain of rASIC3. Overall, these data demonstrate the utility of computational analysis for identifying novel ASIC3 modulators, which can be validated with electrophysiological analysis and may lead to the development of better compounds for targeting ASIC3 in the treatment of inflammatory conditions.
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Affiliation(s)
- Gerard Callejo
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Luke A Pattison
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Jack C Greenhalgh
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Sampurna Chakrabarti
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Evangelia Andreopoulou
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - James R F Hockley
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Ewan St John Smith
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom.
| | - Taufiq Rahman
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom.
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17
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Pattison LA, Callejo G, St John Smith E. Evolution of acid nociception: ion channels and receptors for detecting acid. Philos Trans R Soc Lond B Biol Sci 2019; 374:20190291. [PMID: 31544616 PMCID: PMC6790391 DOI: 10.1098/rstb.2019.0291] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/27/2019] [Indexed: 12/13/2022] Open
Abstract
Nociceptors, i.e. sensory neurons tuned to detect noxious stimuli, are found in numerous phyla of the Animalia kingdom and are often polymodal, responding to a variety of stimuli, e.g. heat, cold, pressure and chemicals, such as acid. Owing to the ability of protons to have a profound effect on ionic homeostasis and damage macromolecular structures, it is no wonder that the ability to detect acid is conserved across many species. To detect changes in pH, nociceptors are equipped with an assortment of different acid sensors, some of which can detect mild changes in pH, such as the acid-sensing ion channels, proton-sensing G protein-coupled receptors and several two-pore potassium channels, whereas others, such as the transient receptor potential vanilloid 1 ion channel, require larger shifts in pH. This review will discuss the evolution of acid sensation and the different mechanisms by which nociceptors can detect acid. This article is part of the Theo Murphy meeting issue 'Evolution of mechanisms and behaviour important for pain'.
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Affiliation(s)
| | | | - Ewan St John Smith
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, UK
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18
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Marine Toxins and Nociception: Potential Therapeutic Use in the Treatment of Visceral Pain Associated with Gastrointestinal Disorders. Toxins (Basel) 2019; 11:toxins11080449. [PMID: 31370176 PMCID: PMC6723473 DOI: 10.3390/toxins11080449] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 07/24/2019] [Accepted: 07/26/2019] [Indexed: 12/12/2022] Open
Abstract
Visceral pain, of which the pathogenic basis is currently largely unknown, is a hallmark symptom of both functional disorders, such as irritable bowel syndrome, and inflammatory bowel disease. Intrinsic sensory neurons in the enteric nervous system and afferent sensory neurons of the dorsal root ganglia, connecting with the central nervous system, represent the primary neuronal pathways transducing gut visceral pain. Current pharmacological therapies have several limitations, owing to their partial efficacy and the generation of severe adverse effects. Numerous cellular targets of visceral nociception have been recognized, including, among others, channels (i.e., voltage-gated sodium channels, VGSCs, voltage-gated calcium channels, VGCCs, Transient Receptor Potential, TRP, and Acid-sensing ion channels, ASICs) and neurotransmitter pathways (i.e., GABAergic pathways), which represent attractive targets for the discovery of novel drugs. Natural biologically active compounds, such as marine toxins, able to bind with high affinity and selectivity to different visceral pain molecular mediators, may represent a useful tool (1) to improve our knowledge of the physiological and pathological relevance of each nociceptive target, and (2) to discover therapeutically valuable molecules. In this review we report the most recent literature describing the effects of marine toxin on gastrointestinal visceral pain pathways and the possible clinical implications in the treatment of chronic pain associated with gut diseases.
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19
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Kim JS, Harms JE, Ruiz-Velasco V, Kaufman MP. Effect of knockout of the ASIC3 on cardiovascular reflexes arising from hindlimb muscle in decerebrated rats. Am J Physiol Regul Integr Comp Physiol 2019; 317:R641-R648. [PMID: 31347922 DOI: 10.1152/ajpregu.00148.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The exercise pressor reflex is initiated by the contraction-induced activation of group III and IV muscle afferents. The reflex is manifested by increases in arterial blood pressure and cardiac output, which, in turn, are generated by increases in the sympathetic outflow to the heart and vasculature and decreases in the vagal outflow to the heart. In previous experiments, we used a pharmacological approach to assess the role played by the acid-sensing ion channel 3 (ASIC3) on group III and IV afferents in evoking the exercise pressor reflex. In the present experiments, we used an alternative approach, namely functional knockout (KO) of the ASIC3 gene, to confirm and extend our previous finding that pharmacological blockade of the ASIC3 had only a small impact on the expression of the exercise pressor reflex when the arterial supply to the contracting hindlimb muscles of rats was patent. Using this alternative approach, we compared the magnitude of the exercise pressor reflex evoked in ASIC3 KO rats with that evoked in their wild-type (WT) counterparts. We found both WT and ASIC3 KO rats displayed similar pressor responses to static contraction (WT, n = 10, +12 ± 2 mmHg; KO, n = 9, +11 ± 2 mmHg) and calcaneal tendon stretch (WT, n = 9, +13 ± 2 mmHg; KO, n = 7, +11 ± 2 mmHg). Likewise, both WT and ASIC3 KO displayed similar pressor responses to intra-arterial injection of 12 mM lactic acid (WT, n = 9, +14 ± 3 mmHg; KO, n = 8, +18 ± 5 mmHg), 24 mM lactic acid (WT, n = 9,+24 ± 2 mmHg; KO, n = 8, +20 ± 5 mmHg), capsaicin (WT, n = 9,+27 ± 5 mmHg; KO, n = 10, +29 ± 5 mmHg), and diprotonated phosphate ([Formula: see text]; WT, n = 6,+22 ± 3 mmHg; KO, n = 6, +32 ± 6 mmHg). We conclude that redundant receptors are responsible for evoking the pressor reflexes arising from group III and IV afferents.
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Affiliation(s)
- Joyce S Kim
- Heart and Vascular Institute and the Departments of Medicine and Anesthesiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Jonathan E Harms
- Heart and Vascular Institute and the Departments of Medicine and Anesthesiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Victor Ruiz-Velasco
- Heart and Vascular Institute and the Departments of Medicine and Anesthesiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Marc P Kaufman
- Heart and Vascular Institute and the Departments of Medicine and Anesthesiology, Penn State College of Medicine, Hershey, Pennsylvania
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20
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Transcriptional Regulation of Voltage-Gated Sodium Channels Contributes to GM-CSF-Induced Pain. J Neurosci 2019; 39:5222-5233. [PMID: 31015342 DOI: 10.1523/jneurosci.2204-18.2019] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Revised: 04/12/2019] [Accepted: 04/15/2019] [Indexed: 11/21/2022] Open
Abstract
Granulocyte-macrophage colony-stimulating factor (GM-CSF) induces the production of granulocyte and macrophage populations from the hematopoietic progenitor cells; it is one of the most common growth factors in the blood. GM-CSF is also involved in bone cancer pain development by regulating tumor-nerve interactions, remodeling of peripheral nerves, and sensitization of damage-sensing (nociceptive) nerves. However, the precise mechanism for GM-CSF-dependent pain is unclear. In this study, we found that GM-CSF is highly expressed in human malignant osteosarcoma. Female Sprague Dawley rats implanted with bone cancer cells develop mechanical and thermal hyperalgesia, but antagonizing GM-CSF in these animals significantly reduced such hypersensitivity. The voltage-gated Na+ channels Nav1.7, Nav1.8, and Nav1.9 were found to be selectively upregulated in rat DRG neurons treated with GM-CSF, which resulted in enhanced excitability. GM-CSF activated the Janus kinase 2 (Jak2)-signal transducer and activator of transcription protein 3 (Stat3) signaling pathway, which promoted the transcription of Nav1.7-1.9 in DRG neurons. Accordingly, targeted knocking down of either Nav1.7-1.9 or Jak2/Stat3 in DRG neurons in vivo alleviated the hyperalgesia in male Sprague Dawley rats. Our findings describe a novel bone cancer pain mechanism and provide a new insight into the physiological and pathological functions of GM-CSF.SIGNIFICANCE STATEMENT It has been reported that granulocyte-macrophage colony-stimulating factor (GM-CSF) plays a key role in bone cancer pain, yet the underlying mechanisms involved in the GM-CSF-mediated signaling pathway in nociceptors is not fully understood. Here, we showed that GM-CSF promotes bone cancer-associated pain by enhancing the excitability of DRG neurons via the Janus kinase 2 (Jak2)-signal transducer and activator of transcription protein 3 (Stat3)-mediated upregulation of expression of nociceptor-specific voltage-gated sodium channels. Our study provides a detailed understanding of the roles that sodium channels and the Jak2/Stat3 pathway play in the GM-CSF-mediated bone cancer pain; our data also highlight the therapeutic potential of targeting GM-CSF.
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21
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Ramírez-Carreto S, Pérez-García EI, Salazar-García SI, Bernáldez-Sarabia J, Licea-Navarro A, Rudiño-Piñera E, Pérez-Martínez L, Pedraza-Alva G, Rodríguez-Almazán C. Identification of a pore-forming protein from sea anemone Anthopleura dowii Verrill (1869) venom by mass spectrometry. J Venom Anim Toxins Incl Trop Dis 2019; 25:e147418. [PMID: 31131002 PMCID: PMC6483413 DOI: 10.1590/1678-9199-jvatitd-1474-18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 11/13/2018] [Indexed: 12/14/2022] Open
Abstract
Background: Pore-forming proteins (PFP) are a class of toxins abundant in the venom of
sea anemones. Owing to their ability to recognize and permeabilize cell
membranes, pore-forming proteins have medical potential in cancer therapy or
as biosensors. In the present study, we showed the partial purification and
sequencing of a pore-forming protein from Anthopleura dowii
Verrill (1869). 17. Methods: Cytolytic activity of A. dowii Verrill (1869) venom was
determined via hemolysis assay in the erythrocytes of four mammals (sheep,
goat, human and rabbit). The cytotoxic activity was analyzed in the human
adherent lung carcinoma epithelial cells (A549) by the cytosolic lactate
dehydrogenase (LDH) assay, and trypan blue staining. The venom was
fractionated via ammonium sulfate precipitation gradient, dialysis, and ion
exchange chromatography. The presence of a pore-forming protein in purified
fractions was evaluated through hemolytic and cytotoxic assays, and the
activity fraction was analyzed using the percent of osmotic protections
after polyethylene glycol (PEG) treatment and mass spectrometry. 18. Results: The amount of protein at which the venom produced 50% hemolysis
(HU50) was determined in hemolysis assays using erythrocytes
from sheep (HU50 = 10.7 ± 0.2 μg), goat (HU50 = 13.2 ±
0.3 μg), rabbit (HU50 = 34.7 ± 0.5 μg), and human
(HU50 = 25.6 ± 0.6 μg). The venom presented a cytotoxic
effect in A549 cells and the protein amount present in the venom responsible
for producing 50% death (IC50) was determined using a trypan blue
cytotoxicity assay (1.84 ± 0.40 μg/mL). The loss of membrane integrity in
the A549 cells caused by the venom was detected by the release of LDH in
proportion to the amount of protein. The venom was fractionated; and the
fraction with hemolytic and cytotoxic activities was analyzed by mass
spectrometry. A pore-forming protein was identified. The cytotoxicity in the
A549 cells produced by the fraction containing the pore-forming protein was
osmotically protected by PEG-3350 Da molecular mass, which corroborated that
the loss of integrity in the plasma membrane was produced via pore
formation. 19. Conclusion: A. dowii Verrill (1869) venom
contains a pore-forming protein suitable for designing new drugs for cancer
therapy.
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Affiliation(s)
- Santos Ramírez-Carreto
- Universidad Nacional Autónoma de México, Instituto de Biotecnología, Departamento de Medicina Molecular y Bioprocesos, Av. Universidad 2001, Cuernavaca, Morelos, México
| | - Erick I Pérez-García
- Universidad Nacional Autónoma de México, Instituto de Biotecnología, Departamento de Medicina Molecular y Bioprocesos, Av. Universidad 2001, Cuernavaca, Morelos, México
| | - Sandra I Salazar-García
- Universidad Nacional Autónoma de México, Instituto de Biotecnología, Departamento de Medicina Molecular y Bioprocesos, Av. Universidad 2001, Cuernavaca, Morelos, México
| | - Johanna Bernáldez-Sarabia
- Centro de Investigación Científica y de Educación Superior de Ensenada, Departamento de Innovación Biomédica, Baja California, México
| | - Alexei Licea-Navarro
- Centro de Investigación Científica y de Educación Superior de Ensenada, Departamento de Innovación Biomédica, Baja California, México
| | - Enrique Rudiño-Piñera
- Universidad Nacional Autónoma de México, Instituto de Biotecnología, Departamento de Medicina Molecular y Bioprocesos, Av. Universidad 2001, Cuernavaca, Morelos, México
| | - Leonor Pérez-Martínez
- Universidad Nacional Autónoma de México, Instituto de Biotecnología, Departamento de Medicina Molecular y Bioprocesos, Av. Universidad 2001, Cuernavaca, Morelos, México
| | - Gustavo Pedraza-Alva
- Universidad Nacional Autónoma de México, Instituto de Biotecnología, Departamento de Medicina Molecular y Bioprocesos, Av. Universidad 2001, Cuernavaca, Morelos, México
| | - Claudia Rodríguez-Almazán
- Universidad Nacional Autónoma de México, Instituto de Biotecnología, Departamento de Medicina Molecular y Bioprocesos, Av. Universidad 2001, Cuernavaca, Morelos, México
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Andreev YA, Osmakov DI, Koshelev SG, Maleeva EE, Logashina YA, Palikov VA, Palikova YA, Dyachenko IA, Kozlov SA. Analgesic Activity of Acid-Sensing Ion Channel 3 (ASIС3) Inhibitors: Sea Anemones Peptides Ugr9-1 and APETx2 versus Low Molecular Weight Compounds. Mar Drugs 2018; 16:E500. [PMID: 30545037 PMCID: PMC6316600 DOI: 10.3390/md16120500] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 12/05/2018] [Accepted: 12/10/2018] [Indexed: 01/10/2023] Open
Abstract
Acid-sensing ion channel 3 (ASIC3) makes an important contribution to the development and maintenance of inflammatory and acid-induced pain. We compared different ASIC3 inhibitors (peptides from sea anemones (APETx2 and Ugr9-1) and nonpeptide molecules (sevanol and diclofenac)) in anti-inflammatory action and analgesic effects. All tested compounds had distinct effects on pH-induced ASIC3 current. APETx2 inhibited only transient current, whereas Ugr9-1 and sevanol decreased transient and sustained components of the current. The effect on mice was evaluated after administering an intramuscular injection in the acetic acid writhing pain model and the complete Freund's adjuvant-induced thermal hyperalgesia/inflammation test. The bell-shaped dependence of the analgesic effect was observed for APETx2 in the acetic acid-induced writhing test, as well as for sevanol and peptide Ugr9-1 in the thermal hyperalgesia test. This dependence could be evidence of the nonspecific action of compounds in high doses. Compounds reducing both components of ASIC3 current produced more significant pain relief than APETx2, which is an effective inhibitor of a transient current only. Therefore, the comparison of the efficacy of ASIC3 inhibitors revealed the importance of ASIC3-sustained currents' inhibition for promotion of acidosis-related pain relief.
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Affiliation(s)
- Yaroslav A Andreev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russia.
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Trubetskaya str. 8, bld. 2, Moscow 119991, Russia.
| | - Dmitry I Osmakov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russia.
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Trubetskaya str. 8, bld. 2, Moscow 119991, Russia.
| | - Sergey G Koshelev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russia.
| | - Ekaterina E Maleeva
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russia.
| | - Yulia A Logashina
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russia.
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Trubetskaya str. 8, bld. 2, Moscow 119991, Russia.
| | - Victor A Palikov
- Branch of the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 6 Nauki Avenue, 142290 Pushchino, Russia.
| | - Yulia A Palikova
- Branch of the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 6 Nauki Avenue, 142290 Pushchino, Russia.
| | - Igor A Dyachenko
- Branch of the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 6 Nauki Avenue, 142290 Pushchino, Russia.
| | - Sergey A Kozlov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russia.
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Nicosia A, Mikov A, Cammarata M, Colombo P, Andreev Y, Kozlov S, Cuttitta A. The Anemonia viridis Venom: Coupling Biochemical Purification and RNA-Seq for Translational Research. Mar Drugs 2018; 16:E407. [PMID: 30366463 PMCID: PMC6266578 DOI: 10.3390/md16110407] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 10/20/2018] [Accepted: 10/24/2018] [Indexed: 11/16/2022] Open
Abstract
Blue biotechnologies implement marine bio-resources for addressing practical concerns. The isolation of biologically active molecules from marine animals is one of the main ways this field develops. Strikingly, cnidaria are considered as sustainable resources for this purpose, as they possess unique cells for attack and protection, producing an articulated cocktail of bioactive substances. The Mediterranean sea anemone Anemonia viridis has been studied extensively for years. In this short review, we summarize advances in bioprospecting of the A. viridis toxin arsenal. A. viridis RNA datasets and toxin data mining approaches are briefly described. Analysis reveals the major pool of neurotoxins of A. viridis, which are particularly active on sodium and potassium channels. This review therefore integrates progress in both RNA-Seq based and biochemical-based bioprospecting of A. viridis toxins for biotechnological exploitation.
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Affiliation(s)
- Aldo Nicosia
- National Research Council-Institute for the Study of Anthropogenic Impacts and Sustainability in the Marine Environment (IAS-CNR), Laboratory of Molecular Ecology and Biotechnology, Capo Granitola, Via del mare, Campobello di Mazara (TP), 91021 Sicily, Italy.
| | - Alexander Mikov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, RAS, GSP-7, ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia.
| | - Matteo Cammarata
- Department of Earth and Marine Sciences, University of Palermo, 90100 Palermo, Italy.
| | - Paolo Colombo
- Istituto di Biomedicina e di Immunologia Molecolare, Consiglio Nazionale delle Ricerche, Via Ugo La Malfa 153, 90146 Palermo, Italy.
| | - Yaroslav Andreev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, RAS, GSP-7, ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia.
- Institute of Molecular Medicine, Ministry of Healthcare of the Russian Federation, Sechenov First Moscow State Medical University, 119991 Moscow, Russia.
| | - Sergey Kozlov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, RAS, GSP-7, ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia.
| | - Angela Cuttitta
- National Research Council-Institute for the Study of Anthropogenic Impacts and Sustainability in the Marine Environment (IAS-CNR), Laboratory of Molecular Ecology and Biotechnology, Capo Granitola, Via del mare, Campobello di Mazara (TP), 91021 Sicily, Italy.
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Cnidarian peptide neurotoxins: a new source of various ion channel modulators or blockers against central nervous systems disease. Drug Discov Today 2018; 24:189-197. [PMID: 30165198 DOI: 10.1016/j.drudis.2018.08.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Revised: 07/13/2018] [Accepted: 08/10/2018] [Indexed: 01/17/2023]
Abstract
Cnidaria provide the largest source of bioactive peptides for new drug development. The venoms contain enzymes, potent pore-forming toxins and neurotoxins. The neurotoxins can immobilize predators rapidly when discharged via modifying sodium-channel-gating or blocking the potassium channel during the repolarization stage. Most cnidarian neurotoxins remain conserved under the strong influence of negative selection. Neuroactive peptides targeting the central nervous system through affinity with ion channels could provide insight leading to drug treatment of neurological diseases, which arise from ion channel dysfunctions. Although marine resources offer thousands of possible peptides, only one peptide derived from Cnidaria: ShK-186, also named dalazatide, has reached the pharmaceutical market. This review focuses on neuroprotective agents derived from cnidarian neurotoxic peptides.
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25
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Toxins as tools: Fingerprinting neuronal pharmacology. Neurosci Lett 2018; 679:4-14. [DOI: 10.1016/j.neulet.2018.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 01/09/2018] [Accepted: 02/02/2018] [Indexed: 12/30/2022]
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Hamad MK, He K, Abdulrazeq HF, Mustafa AM, Luceri R, Kamal N, Ali M, Nakhla J, Herzallah MM, Mammis A. Potential Uses of Isolated Toxin Peptides in Neuropathic Pain Relief: A Literature Review. World Neurosurg 2018; 113:333-347.e5. [DOI: 10.1016/j.wneu.2018.01.116] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 01/15/2018] [Accepted: 01/16/2018] [Indexed: 01/31/2023]
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Zhou X, Zhang Y, Tang D, Liang S, Chen P, Tang C, Liu Z. A Chimeric NaV1.8 Channel Expression System Based on HEK293T Cell Line. Front Pharmacol 2018; 9:337. [PMID: 29686617 PMCID: PMC5900924 DOI: 10.3389/fphar.2018.00337] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 03/22/2018] [Indexed: 11/13/2022] Open
Abstract
Among the nine voltage-gated sodium channel (NaV) subtypes, NaV1.8 is an attractive therapeutic target for pain. The heterologous expression of recombinant NaV1.8 currents is of particular importance for its electrophysiological and pharmacological studies. However, NaV1.8 expresses no or low-level functional currents when transiently transfected into non-neuronal cell lines. The present study aims to explore the molecular determinants limiting its functional expression and accordingly establish a functional NaV1.8 expression system. We conducted screening analysis of the NaV1.8 intracellular loops by constructing NaV chimeric channels and confirmed that the NaV1.8 C-terminus was the only limiting factor. Replacing this sequence with that of NaV1.4, NaV1.5, or NaV1.7 constructed functional channels (NaV1.8/1.4L5, NaV1.8/1.5L5, and NaV1.8/1.7L5, respectively), which expressed high-level NaV1.8-like currents in HEK293T cells. The chimeric channel NaV1.8/1.7L5 displayed much faster inactivation of its macroscopic currents than NaV1.8/1.4L5 and NaV1.8/1.5L5, and it was the most similar to wild-type NaV1.8 expressed in ND7/23 cells. Its currents were very stable during repetitive depolarizations, while its repriming kinetic was different from wild-type NaV1.8. Most importantly, NaV1.8/1.7L5 pharmacologically resembled wild-type NaV1.8 as revealed by testing their susceptibility to two NaV1.8 selective antagonists, APETx-2 and MrVIB. NaV chimeras study showed that at least the domain 2 and domain 4 of NaV1.8 were involved in binding with APETx-2. Our study provided new insights into the function of NaV1.8 intracellular loops, as well as a reliable and convenient expression system which could be useful in NaV1.8 studies.
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Affiliation(s)
| | | | | | | | | | - Cheng Tang
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Zhonghua Liu
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China
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Wu Y, Ma H, Zhang F, Zhang C, Zou X, Cao Z. Selective Voltage-Gated Sodium Channel Peptide Toxins from Animal Venom: Pharmacological Probes and Analgesic Drug Development. ACS Chem Neurosci 2018; 9:187-197. [PMID: 29161016 DOI: 10.1021/acschemneuro.7b00406] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Voltage-gated sodium channels (Navs) play critical roles in action potential generation and propagation. Nav channelopathy as well as pathological sensitization contribute to allodynia and hyperalgesia. Recent evidence has demonstrated the significant roles of Nav subtypes (Nav1.3, 1.7, 1.8, and 1.9) in nociceptive transduction, and therefore these Navs may represent attractive targets for analgesic drug discovery. Animal toxins are structurally diverse peptides that are highly potent yet selective on ion channel subtypes and therefore represent valuable probes to elucidate the structures, gating properties, and cellular functions of ion channels. In this review, we summarize recent advances on peptide toxins from animal venom that selectively target Nav1.3, 1.7, 1.8, and 1.9, along with their potential in analgesic drug discovery.
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Affiliation(s)
- Ying Wu
- Jiangsu Provincial Key Laboratory for TCM Evaluation
and Translational Development, China Pharmaceutical University, Nanjing 211198, China
| | - Hui Ma
- Jiangsu Provincial Key Laboratory for TCM Evaluation
and Translational Development, China Pharmaceutical University, Nanjing 211198, China
| | - Fan Zhang
- Jiangsu Provincial Key Laboratory for TCM Evaluation
and Translational Development, China Pharmaceutical University, Nanjing 211198, China
| | - Chunlei Zhang
- Jiangsu Provincial Key Laboratory for TCM Evaluation
and Translational Development, China Pharmaceutical University, Nanjing 211198, China
| | - Xiaohan Zou
- Jiangsu Provincial Key Laboratory for TCM Evaluation
and Translational Development, China Pharmaceutical University, Nanjing 211198, China
| | - Zhengyu Cao
- Jiangsu Provincial Key Laboratory for TCM Evaluation
and Translational Development, China Pharmaceutical University, Nanjing 211198, China
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29
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PhcrTx2, a New Crab-Paralyzing Peptide Toxin from the Sea Anemone Phymanthus crucifer. Toxins (Basel) 2018; 10:toxins10020072. [PMID: 29414882 PMCID: PMC5848173 DOI: 10.3390/toxins10020072] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 02/01/2018] [Accepted: 02/02/2018] [Indexed: 12/22/2022] Open
Abstract
Sea anemones produce proteinaceous toxins for predation and defense, including peptide toxins that act on a large variety of ion channels of pharmacological and biomedical interest. Phymanthus crucifer is commonly found in the Caribbean Sea; however, the chemical structure and biological activity of its toxins remain unknown, with the exception of PhcrTx1, an acid-sensing ion channel (ASIC) inhibitor. Therefore, in the present work, we focused on the isolation and characterization of new P. crucifer toxins by chromatographic fractionation, followed by a toxicity screening on crabs, an evaluation of ion channels, and sequence analysis. Five groups of toxic chromatographic fractions were found, and a new paralyzing toxin was purified and named PhcrTx2. The toxin inhibited glutamate-gated currents in snail neurons (maximum inhibition of 35%, IC50 4.7 µM), and displayed little or no influence on voltage-sensitive sodium/potassium channels in snail and rat dorsal root ganglion (DRG) neurons, nor on a variety of cloned voltage-gated ion channels. The toxin sequence was fully elucidated by Edman degradation. PhcrTx2 is a new β-defensin-fold peptide that shares a sequence similarity to type 3 potassium channels toxins. However, its low activity on the evaluated ion channels suggests that its molecular target remains unknown. PhcrTx2 is the first known paralyzing toxin in the family Phymanthidae.
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30
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Lee JYP, Saez NJ, Cristofori-Armstrong B, Anangi R, King GF, Smith MT, Rash LD. Inhibition of acid-sensing ion channels by diminazene and APETx2 evoke partial and highly variable antihyperalgesia in a rat model of inflammatory pain. Br J Pharmacol 2018; 175:2204-2218. [PMID: 29134638 DOI: 10.1111/bph.14089] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2017] [Revised: 10/22/2017] [Accepted: 10/31/2017] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND AND PURPOSE Acid-sensing ion channels (ASICs) are primary acid sensors in mammals, with the ASIC1b and ASIC3 subtypes being involved in peripheral nociception. The antiprotozoal drug diminazene is a moderately potent ASIC inhibitor, but its analgesic activity has not been assessed. EXPERIMENTAL APPROACH We determined the ASIC subtype selectivity of diminazene and the mechanism by which it inhibits ASICs using voltage-clamp electrophysiology of Xenopus oocytes expressing ASICs 1-3. Its peripheral analgesic activity was then assessed relative to APETx2, an ASIC3 inhibitor, and morphine, in a Freund's complete adjuvant (FCA)-induced rat model of inflammatory pain. KEY RESULTS Diminazene inhibited homomeric rat ASICs with IC50 values of ~200-800 nM, via an open channel and subtype-dependent mechanism. In rats with FCA-induced inflammatory pain in one hindpaw, diminazene and APETx2 evoked more potent peripheral antihyperalgesia than morphine, but the effect was partial for APETx2. APETx2 potentiated rat ASIC1b at concentrations 30-fold to 100-fold higher than the concentration inhibiting ASIC3, which may have implications for its use in in vivo experiments. CONCLUSIONS AND IMPLICATIONS Diminazene and APETx2 are moderately potent ASIC inhibitors, both inducing peripheral antihyperalgesia in a rat model of chronic inflammatory pain. APETx2 has a more complex ASIC pharmacology, which must be considered when it is used as a supposedly selective ASIC3 inhibitor in vivo. Our use of outbred rats revealed responders and non-responders when ASIC inhibition was used to alleviate inflammatory pain, which is aligned with the concept of number-needed-to-treat in human clinical studies. LINKED ARTICLES This article is part of a themed section on Recent Advances in Targeting Ion Channels to Treat Chronic Pain. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.12/issuetoc.
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Affiliation(s)
- Jia Yu Peppermint Lee
- UQ Centre for Clinical Research, Faculty of Medicine, The University of Queensland, St Lucia, QLD, Australia
| | - Natalie J Saez
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
| | | | - Raveendra Anangi
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
| | - Glenn F King
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
| | - Maree T Smith
- UQ Centre for Clinical Research, Faculty of Medicine, The University of Queensland, St Lucia, QLD, Australia.,School of Pharmacy, The University of Queensland, St Lucia, QLD, Australia
| | - Lachlan D Rash
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia.,School of Biomedical Sciences, The University of Queensland, St Lucia, QLD, Australia
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Wu J, Liu TT, Zhou YM, Qiu CY, Ren P, Jiao M, Hu WP. Sensitization of ASIC3 by proteinase-activated receptor 2 signaling contributes to acidosis-induced nociception. J Neuroinflammation 2017; 14:150. [PMID: 28754162 PMCID: PMC5534107 DOI: 10.1186/s12974-017-0916-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 07/11/2017] [Indexed: 02/07/2023] Open
Abstract
Background Tissue acidosis and inflammatory mediators play critical roles in pain. Pro-inflammatory agents trypsin and tryptase cleave and activate proteinase-activated receptor 2 (PAR2) expressed on sensory nerves, which is involved in peripheral mechanisms of inflammation and pain. Extracellular acidosis activates acid-sensing ion channel 3 (ASIC3) to trigger pain sensation. Here, we show that a functional interaction of PAR2 and ASIC3 could contribute to acidosis-induced nociception. Methods Electrophysiological experiments were performed on both rat DRG neurons and Chinese hamster ovary (CHO) cells expressing ASIC3 and PAR2. Nociceptive behavior was induced by acetic acid in rats. Results PAR2-AP, PAR2-activating peptide, concentration-dependently increased the ASIC3 currents in CHO cells transfected with ASIC3 and PAR2. The proton concentration–response relationship was not changed, but that the maximal response increased 58.7 ± 3.8% after pretreatment of PAR2-AP. PAR2 mediated the potentiation of ASIC3 currents via an intracellular cascade. PAR2-AP potentiation of ASIC3 currents disappeared after inhibition of intracellular G protein, PLC, PKC, or PKA signaling. Moreover, PAR2 activation increased proton-evoked currents and spikes mediated by ASIC3 in rat dorsal root ganglion neurons. Finally, peripheral administration of PAR2-AP dose-dependently exacerbated acidosis-induced nocifensive behaviors in rats. Conclusions These results indicated that PAR2 signaling sensitized ASIC3, which may contribute to acidosis-induced nociception. These represent a novel peripheral mechanism underlying PAR2 involvement in hyperalgesia by sensitizing ASIC3 in primary sensory neurons.
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Affiliation(s)
- Jing Wu
- Research Center of Basic Medical Sciences, School of Basic Medical Sciences, Hubei University of Science and Technology, 88 Xianning Road, Xianning, 437100, Hubei, People's Republic of China
| | - Ting-Ting Liu
- Research Center of Basic Medical Sciences, School of Basic Medical Sciences, Hubei University of Science and Technology, 88 Xianning Road, Xianning, 437100, Hubei, People's Republic of China.,Department of Physiology, School of Basic Medical Sciences, Hubei University of Science and Technology, 88 Xianning Road, Xianning, 437100, Hubei, People's Republic of China
| | - Yi-Mei Zhou
- Research Center of Basic Medical Sciences, School of Basic Medical Sciences, Hubei University of Science and Technology, 88 Xianning Road, Xianning, 437100, Hubei, People's Republic of China
| | - Chun-Yu Qiu
- Department of Pharmacology, Hubei University of Science and Technology, 88 Xianning Road, Xianning, 437100, Hubei, People's Republic of China
| | - Ping Ren
- Department of Pharmacology, Hubei University of Science and Technology, 88 Xianning Road, Xianning, 437100, Hubei, People's Republic of China
| | - Ming Jiao
- Research Center of Basic Medical Sciences, School of Basic Medical Sciences, Hubei University of Science and Technology, 88 Xianning Road, Xianning, 437100, Hubei, People's Republic of China.
| | - Wang-Ping Hu
- Research Center of Basic Medical Sciences, School of Basic Medical Sciences, Hubei University of Science and Technology, 88 Xianning Road, Xianning, 437100, Hubei, People's Republic of China. .,Department of Physiology, School of Basic Medical Sciences, Hubei University of Science and Technology, 88 Xianning Road, Xianning, 437100, Hubei, People's Republic of China.
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Yang L, Craviso GL, Vernier PT, Chatterjee I, Leblanc N. Nanosecond electric pulses differentially affect inward and outward currents in patch clamped adrenal chromaffin cells. PLoS One 2017; 12:e0181002. [PMID: 28700658 PMCID: PMC5507283 DOI: 10.1371/journal.pone.0181002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 06/23/2017] [Indexed: 11/18/2022] Open
Abstract
This study examined the effect of 5 ns electric pulses on macroscopic ionic currents in whole-cell voltage-clamped adrenal chromaffin cells. Current-voltage (I-V) relationships first established that the early peak inward current was primarily composed of a fast voltage-dependent Na+ current (INa), whereas the late outward current was composed of at least three ionic currents: a voltage-gated Ca2+ current (ICa), a Ca2+-activated K+ current (IK(Ca)), and a sustained voltage-dependent delayed rectifier K+ current (IKV). A constant-voltage step protocol was next used to monitor peak inward and late outward currents before and after cell exposure to a 5 ns pulse. A single pulse applied at an electric (E)-field amplitude of 5 MV/m resulted in an instantaneous decrease of ~4% in peak INa that then declined exponentially to a level that was ~85% of the initial level after 10 min. Increasing the E-field amplitude to 8 or 10 MV/m caused a twofold greater inhibitory effect on peak INa. The decrease in INa was not due to a change in either the steady-state inactivation or activation of the Na+ channel but instead was associated with a decrease in maximal Na+ conductance. Late outward current was not affected by a pulse applied at 5 MV/m. However, for a pulse applied at the higher E-field amplitudes of 8 and 10 MV/m, late outward current in some cells underwent a progressive ~22% decline over the course of the first 20 s following pulse exposure, with no further decline. The effect was most likely concentrated on ICa and IK(Ca) as IKV was not affected. The results of this study indicate that in whole-cell patch clamped adrenal chromaffin cells, a 5 ns pulse differentially inhibits specific voltage-gated ionic currents in a manner that can be manipulated by tuning E-field amplitude.
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Affiliation(s)
- Lisha Yang
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, NV, United States of America
| | - Gale L. Craviso
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, NV, United States of America
| | - P. Thomas Vernier
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA, United States of America
| | - Indira Chatterjee
- Department of Electrical and Biomedical Engineering, College of Engineering, University of Nevada, Reno, NV, United States of America
| | - Normand Leblanc
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, NV, United States of America
- Center for Cardiovascular Research, University of Nevada, Reno School of Medicine, Reno, NV, United States of America
- * E-mail:
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Effect of an Acid-sensing Ion Channels Inhibitor on Pain-related Behavior by Nucleus Pulposus Applied on the Nerve Root in Rats. Spine (Phila Pa 1976) 2017; 42:E633-E641. [PMID: 27879566 DOI: 10.1097/brs.0000000000001918] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Controlled, interventional animal study. OBJECTIVE To examine the effect of an inhibitor of acid-sensing ion channel 3 (ASIC3) on pain-related behavior induced by application of the nucleus pulposus (NP) onto the dorsal root ganglion (DRG) in rats. SUMMARY OF BACKGROUND DATA ASIC3 is associated with acidosis pain in inflamed or ischemic tissues and is expressed in sensory neurons and NP cells. The ASIC3 inhibitor, APETx2, increases the mechanical threshold of pain in models of knee osteoarthritis or postoperative pain. However, the efficacy of APETx2 for pain relief in the NP application model remains unknown. METHODS Autologous NP was applied to the left L5 nerve root of 183 adult female Sprague-Dawley rats. The DRGs were treated with NP plus one of the following four treatments: saline solution (SM), low (0.01 μg: LD), medium (0.1 μg: MD), or high dose (1.0 μg: HD) of APETx2. Behavioral testing was performed to investigate the mechanical withdrawal threshold using von Frey hairs. Expression of nerve growth factor, hypoxia-inducible factor-1α (HIF1α), activating transcription factor-3, and ionized calcium-binding adaptor molecule-1 was evaluated using immunohistochemistry. Statistical differences among multiple groups were assessed using the Steel test, the Tukey-Kramer test, and the Dunnett test. P < 0.05 were considered significant. RESULTS The thresholds in the HD group were higher than those in the SM group at Days 14 and 21 (P < 0.05). In the MD group, the threshold was higher than in the SM group at Day 14 (P < 0.05). High doses of APETx2 reduced the expression of HIF1α after Day 14 compared with the SM group (P < 0.05). CONCLUSION APETx2 significantly improved pain-related behavior in a dose-dependent manner. APETx2 may inhibit ASIC3 and partly inhibit Nav1.8 channels. This ASIC3 channel inhibitor may be a potential therapeutic agent in early-stage lumbar disc herniation. LEVEL OF EVIDENCE N/A.
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Acid-sensing ion channel (ASIC) structure and function: Insights from spider, snake and sea anemone venoms. Neuropharmacology 2017; 127:173-184. [PMID: 28457973 DOI: 10.1016/j.neuropharm.2017.04.042] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 04/07/2017] [Accepted: 04/27/2017] [Indexed: 01/14/2023]
Abstract
Acid-sensing ion channels (ASICs) are proton-activated cation channels that are expressed in a variety of neuronal and non-neuronal tissues. As proton-gated channels, they have been implicated in many pathophysiological conditions where pH is perturbed. Venom derived compounds represent the most potent and selective modulators of ASICs described to date, and thus have been invaluable as pharmacological tools to study ASIC structure, function, and biological roles. There are now ten ASIC modulators described from animal venoms, with those from snakes and spiders favouring ASIC1, while the sea anemones preferentially target ASIC3. Some modulators, such as the prototypical ASIC1 modulator PcTx1 have been studied in great detail, while some of the newer members of the club remain largely unstudied. Here we review the current state of knowledge on venom derived ASIC modulators, with a particular focus on their molecular interaction with ASICs, what they have taught us about channel structure, and what they might still reveal about ASIC function and pathophysiological roles. This article is part of the Special Issue entitled 'Venom-derived Peptides as Pharmacological Tools.'
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Rash LD. Acid-Sensing Ion Channel Pharmacology, Past, Present, and Future …. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2017; 79:35-66. [PMID: 28528673 DOI: 10.1016/bs.apha.2017.02.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
pH is one of the most strictly controlled parameters in mammalian physiology. An extracellular pH of ~7.4 is crucial for normal physiological processes, and perturbations to this have profound effects on cell function. Acidic microenvironments occur in many physiological and pathological conditions, including inflammation, bone remodeling, ischemia, trauma, and intense synaptic activity. Cells exposed to these conditions respond in different ways, from tumor cells that thrive to neurons that are either suppressed or hyperactivated, often fatally. Acid-sensing ion channels (ASICs) are primary pH sensors in mammals and are expressed widely in neuronal and nonneuronal cells. There are six main subtypes of ASICs in rodents that can form homo- or heteromeric channels resulting in many potential combinations. ASICs are present and activated under all of the conditions mentioned earlier, suggesting that they play an important role in how cells respond to acidosis. Compared to many other ion channel families, ASICs were relatively recently discovered-1997-and there is a substantial lack of potent, subtype-selective ligands that can be used to elucidate their structural and functional properties. In this chapter I cover the history of ASIC channel pharmacology, which began before the proteins were even identified, and describe the current arsenal of tools available, their limitations, and take a glance into the future to predict from where new tools are likely to emerge.
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Affiliation(s)
- Lachlan D Rash
- School of Biomedical Sciences, The University of Queensland, St Lucia, QLD, Australia.
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Boscardin E, Alijevic O, Hummler E, Frateschi S, Kellenberger S. The function and regulation of acid-sensing ion channels (ASICs) and the epithelial Na(+) channel (ENaC): IUPHAR Review 19. Br J Pharmacol 2016; 173:2671-701. [PMID: 27278329 DOI: 10.1111/bph.13533] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 05/19/2016] [Accepted: 06/02/2016] [Indexed: 12/30/2022] Open
Abstract
Acid-sensing ion channels (ASICs) and the epithelial Na(+) channel (ENaC) are both members of the ENaC/degenerin family of amiloride-sensitive Na(+) channels. ASICs act as proton sensors in the nervous system where they contribute, besides other roles, to fear behaviour, learning and pain sensation. ENaC mediates Na(+) reabsorption across epithelia of the distal kidney and colon and of the airways. ENaC is a clinically used drug target in the context of hypertension and cystic fibrosis, while ASIC is an interesting potential target. Following a brief introduction, here we will review selected aspects of ASIC and ENaC function. We discuss the origin and nature of pH changes in the brain and the involvement of ASICs in synaptic signalling. We expose how in the peripheral nervous system, ASICs cover together with other ion channels a wide pH range as proton sensors. We introduce the mechanisms of aldosterone-dependent ENaC regulation and the evidence for an aldosterone-independent control of ENaC activity, such as regulation by dietary K(+) . We then provide an overview of the regulation of ENaC by proteases, a topic of increasing interest over the past few years. In spite of the profound differences in the physiological and pathological roles of ASICs and ENaC, these channels share many basic functional and structural properties. It is likely that further research will identify physiological contexts in which ASICs and ENaC have similar or overlapping roles.
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Affiliation(s)
- Emilie Boscardin
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Omar Alijevic
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Edith Hummler
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
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The Spinal Cord Has an Intrinsic System for the Control of pH. Curr Biol 2016; 26:1346-51. [DOI: 10.1016/j.cub.2016.03.048] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 03/21/2016] [Accepted: 03/22/2016] [Indexed: 01/10/2023]
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38
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Jalalvand E, Robertson B, Wallén P, Grillner S. Ciliated neurons lining the central canal sense both fluid movement and pH through ASIC3. Nat Commun 2016; 7:10002. [PMID: 26743691 PMCID: PMC4729841 DOI: 10.1038/ncomms10002] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 10/26/2015] [Indexed: 01/02/2023] Open
Abstract
Cerebrospinal fluid-contacting (CSF-c) cells are found in all vertebrates but their function has remained elusive. We recently identified one type of laterally projecting CSF-c cell in lamprey spinal cord with neuronal properties that expresses GABA and somatostatin. We show here that these CSF-c neurons respond to both mechanical stimulation and to lowered pH. These effects are most likely mediated by ASIC3-channels, since APETx2, a specific antagonist of ASIC3, blocks them both. Furthermore, lowering of pH as well as application of somatostatin will reduce the locomotor burst rate. The somatostatin receptor antagonist counteracts the effects of both a decrease in pH and of somatostatin. Lateral bending movement imposed on the spinal cord, as would occur during natural swimming, activates CSF-c neurons. Taken together, we show that CSF-c neurons act both as mechanoreceptors and as chemoreceptors through ASIC3 channels, and their action may protect against pH-changes resulting from excessive neuronal activity.
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Affiliation(s)
- Elham Jalalvand
- The Nobel Institute for Neurophysiology, Department of Neuroscience, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Brita Robertson
- The Nobel Institute for Neurophysiology, Department of Neuroscience, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Peter Wallén
- The Nobel Institute for Neurophysiology, Department of Neuroscience, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Sten Grillner
- The Nobel Institute for Neurophysiology, Department of Neuroscience, Karolinska Institutet, Stockholm SE-171 77, Sweden
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Munro G, Christensen JK, Erichsen HK, Dyhring T, Demnitz J, Dam E, Ahring PK. NS383 Selectively Inhibits Acid-Sensing Ion Channels Containing 1a and 3 Subunits to Reverse Inflammatory and Neuropathic Hyperalgesia in Rats. CNS Neurosci Ther 2015; 22:135-45. [PMID: 26663905 DOI: 10.1111/cns.12487] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 10/30/2015] [Accepted: 10/30/2015] [Indexed: 12/22/2022] Open
Abstract
AIMS Here, we investigate the pharmacology of NS383, a novel small molecule inhibitor of acid-sensing ion channels (ASICs). METHODS ASIC inhibition by NS383 was characterized in patch-clamp electrophysiological studies. Analgesic properties were evaluated in four rat behavioral models of pain. RESULTS NS383 inhibited H(+)-activated currents recorded from rat homomeric ASIC1a, ASIC3, and heteromeric ASIC1a+3 with IC50 values ranging from 0.61 to 2.2 μM. However, NS383 was completely inactive at homomeric ASIC2a. Heteromeric receptors containing AISC2a, such as ASIC1a+2a and ASIC2a+3, were only partially inhibited, presumably as a result of stoichiometry-dependent binding. NS383 (10-60 mg/kg, i.p.), amiloride (50-200 mg/kg, i.p.), acetaminophen (100-400 mg/kg, i.p.), and morphine (3-10 mg/kg, i.p.) all dose-dependently attenuated nocifensive behaviors in the rat formalin test, reversed pathological inflammatory hyperalgesia in complete Freund's adjuvant-inflamed rats, and reversed mechanical hypersensitivity in the chronic constriction injury model of neuropathic pain. However, in contrast to acetaminophen and morphine, motor function was unaffected by NS383 at doses at least 8-fold greater than those that were effective in pain models, whilst analgesic doses of amiloride were deemed to be toxic. CONCLUSIONS NS383 is a potent and uniquely selective inhibitor of rat ASICs containing 1a and/or 3 subunits. It is well tolerated and capable of reversing pathological painlike behaviors, presumably via peripheral actions, but possibly also via actions within central pain circuits.
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Affiliation(s)
| | | | | | - Tino Dyhring
- NeuroSearch A/S, Ballerup, Denmark.,Saniona A/S, Ballerup, Denmark
| | | | - Eva Dam
- NeuroSearch A/S, Ballerup, Denmark
| | - Philip K Ahring
- NeuroSearch A/S, Ballerup, Denmark.,Saniona A/S, Ballerup, Denmark.,Faculty of Pharmacy, The University of Sydney, Sydney, NSW, Australia
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40
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Cristofori-Armstrong B, Soh MS, Talwar S, Brown DL, Griffin JDO, Dekan Z, Stow JL, King GF, Lynch JW, Rash LD. Xenopus borealis as an alternative source of oocytes for biophysical and pharmacological studies of neuronal ion channels. Sci Rep 2015; 5:14763. [PMID: 26440210 PMCID: PMC4594035 DOI: 10.1038/srep14763] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 09/07/2015] [Indexed: 01/10/2023] Open
Abstract
For the past 30 years, oocytes from Xenopus laevis have been extensively used to express and characterise ion channels in an easily controlled environment. Here we report the first use of oocytes from the closely related species Xenopus borealis as an alternative expression system for neuronal ion channels. Using the two-electrode voltage-clamp technique, we show that a wide variety of voltage- and ligand-gated ion channels have the same channel properties and pharmacological profiles when expressed in either X. laevis or X. borealis oocytes. Potential advantages of the X. borealis oocytes include a smaller endogenous chloride current and the ability to produce more intense fluorescence signals when studied with voltage-clamp fluorometry. Scanning electron microscopy revealed a difference in vitelline membrane structure between the two species, which may be related to the discrepancy in fluorescence signals observed. We demonstrate that X. borealis oocytes are a viable heterologous system for expression of neuronal ion channels with some potential advantages over X. laevis oocytes for certain applications.
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Affiliation(s)
| | - Ming S Soh
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Sahil Talwar
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Darren L Brown
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia
| | - John D O Griffin
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Zoltan Dekan
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Jennifer L Stow
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Glenn F King
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Joseph W Lynch
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD 4072, Australia.,School of Biomedical Sciences, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Lachlan D Rash
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia
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Kharatmal S, Singh J, Sharma S. Comparative evaluation of in vitro and in vivo high glucose-induced alterations in voltage-gated tetrodotoxin-resistant sodium channel: Effects attenuated by sodium channel blockers. Neuroscience 2015; 305:183-96. [DOI: 10.1016/j.neuroscience.2015.07.085] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 07/24/2015] [Accepted: 07/31/2015] [Indexed: 10/23/2022]
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42
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Osmakov DI, Andreev YA, Kozlov SA. Acid-sensing ion channels and their modulators. BIOCHEMISTRY (MOSCOW) 2015; 79:1528-45. [PMID: 25749163 DOI: 10.1134/s0006297914130069] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
According to a modern look acid-sensing ion channels (ASICs) are one of the most important receptors that perceive pH change in the body. ASICs represent proton-gated Na+-selective channels, which are expressed in neurons of the central and peripheral nervous system. These channels are attracting attention of researchers around the world, as they are involved in various physiological processes in the body. Drop of pH may occur in tissues in norm (e.g. the accumulation of lactic acid, the release of protons upon ATP hydrolysis) and pathology (inflammation, ischemic stroke, tissue damage and seizure). These processes are accompanied by unpleasant pain sensations, which may be short-lived or can lead to chronic inflammatory diseases. Modulators of ASIC channels activity are potential candidates for new effective analgesic and neuroprotection drugs. This review summarizes available information about structure, function, and physiological role of ASIC channels. In addition a description of all known ligands of these channels and their practical relevance is provided.
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Affiliation(s)
- D I Osmakov
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia.
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43
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α-Dendrotoxin inhibits the ASIC current in dorsal root ganglion neurons from rat. Neurosci Lett 2015; 606:42-7. [PMID: 26314509 DOI: 10.1016/j.neulet.2015.08.034] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 08/11/2015] [Accepted: 08/19/2015] [Indexed: 11/23/2022]
Abstract
Dendrotoxins are a group of peptide toxins purified from the venom of several mamba snakes. α-Dendrotoxin (α-DTx, from the Eastern green mamba Dendroaspis angusticeps) is a well-known blocker of voltage-gated K(+) channels and specifically of K(v)1.1, K(v)1.2 and K(v)1.6. In this work we show that α-DTx inhibited the ASIC currents in DRG neurons (IC50=0.8 μM) when continuously perfused during 25 s (including a 5 s pulse to pH 6.1), but not when co-applied with the pH drop. Additionally, we show that α-DTx abolished a transient component of the outward current that, in some experiments, appeared immediately after the end of the acid pulse. Our data indicate that α-DTx inhibits ASICs in the high nM range while some Kv are inhibited in the low nM range. The α-DTx selectivity and its potential interaction with ASICs should be taken in consideration when DTx is used in the high nM range.
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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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45
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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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46
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Deval E, Lingueglia E. Acid-Sensing Ion Channels and nociception in the peripheral and central nervous systems. Neuropharmacology 2015; 94:49-57. [PMID: 25724084 DOI: 10.1016/j.neuropharm.2015.02.009] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 02/10/2015] [Accepted: 02/12/2015] [Indexed: 11/17/2022]
Abstract
Since their molecular cloning in the late 90's, Acid-Sensing Ion Channels (ASICs) have been shown to be involved in many aspects of nociception, both in peripheral and central neurons. In rodents, the combination of specific or non-specific pharmacological modulators of ASICs, together with in vivo knockdown and/or knockout animals has revealed their contribution to the detection, the modulation and the sensitization of the pain message by primary and secondary sensory neurons. Functional ASICs are homo or heterotrimers of different homologous subunits (ASIC1-3). Channels containing ASIC3 or ASIC1 subunits, appear to be important in peripheral nociceptors, where they are subject to intense regulation, while ASIC1a-containing channels also have a prominent role in central neurons, including spinal cord neurons that modulate and transmit the pain signal to the brain. In humans, experiments performed in healthy volunteers using drugs already used in the clinic and acting as poorly-selective inhibitors of ASICs, together with recent in vitro data obtained from stem cell-derived sensory neurons both support a role for these channels in nociception. These data thus suggest a real translational potential in the development of inhibitory strategies of ASICs for the treatment of pain. This article is part of the Special Issue entitled 'Acid-Sensing Ion Channels in the Nervous System'.
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Affiliation(s)
- Emmanuel Deval
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275, 06560 Valbonne, France; Université de Nice Sophia Antipolis, UMR 7275, 06560 Valbonne, France; LabEx Ion Channel Science and Therapeutics, UMR 7275, 06560 Valbonne, France.
| | - Eric Lingueglia
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), UMR 7275, 06560 Valbonne, France; Université de Nice Sophia Antipolis, UMR 7275, 06560 Valbonne, France; LabEx Ion Channel Science and Therapeutics, UMR 7275, 06560 Valbonne, France
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Jensen JE, Cristofori-Armstrong B, Anangi R, Rosengren KJ, Lau CHY, Mobli M, Brust A, Alewood PF, King GF, Rash LD. Understanding the molecular basis of toxin promiscuity: the analgesic sea anemone peptide APETx2 interacts with acid-sensing ion channel 3 and hERG channels via overlapping pharmacophores. J Med Chem 2014; 57:9195-203. [PMID: 25337890 DOI: 10.1021/jm501400p] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The sea anemone peptide APETx2 is a potent and selective blocker of acid-sensing ion channel 3 (ASIC3). APETx2 is analgesic in a variety of rodent pain models, but the lack of knowledge of its pharmacophore and binding site on ASIC3 has impeded development of improved analogues. Here we present a detailed structure-activity relationship study of APETx2. Determination of a high-resolution structure of APETx2 combined with scanning mutagenesis revealed a cluster of aromatic and basic residues that mediate its interaction with ASIC3. We show that APETx2 also inhibits the off-target hERG channel by reducing the maximal current amplitude and shifting the voltage dependence of activation to more positive potentials. Electrophysiological screening of selected APETx2 mutants revealed partial overlap between the surfaces on APETx2 that mediate its interaction with ASIC3 and hERG. Characterization of the molecular basis of these interactions is an important first step toward the rational design of more selective APETx2 analogues.
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Affiliation(s)
- Jonas E Jensen
- Institute for Molecular Bioscience, ‡School of Biomedical Sciences, and §Centre for Advanced Imaging, The University of Queensland , St Lucia, QLD 4072, Australia
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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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49
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Boillat A, Alijevic O, Kellenberger S. Calcium entry via TRPV1 but not ASICs induces neuropeptide release from sensory neurons. Mol Cell Neurosci 2014; 61:13-22. [DOI: 10.1016/j.mcn.2014.04.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 03/14/2014] [Accepted: 04/23/2014] [Indexed: 11/25/2022] Open
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50
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Chen WN, Lee CH, Lin SH, Wong CW, Sun WH, Wood JN, Chen CC. Roles of ASIC3, TRPV1, and NaV1.8 in the transition from acute to chronic pain in a mouse model of fibromyalgia. Mol Pain 2014; 10:40. [PMID: 24957987 PMCID: PMC4083869 DOI: 10.1186/1744-8069-10-40] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 06/18/2014] [Indexed: 01/23/2023] Open
Abstract
Background Tissue acidosis is effective in causing chronic muscle pain. However, how muscle nociceptors contribute to the transition from acute to chronic pain is largely unknown. Results Here we showed that a single intramuscular acid injection induced a priming effect on muscle nociceptors of mice. The primed muscle nociceptors were plastic and permitted the development of long-lasting chronic hyperalgesia induced by a second acid insult. The plastic changes of muscle nociceptors were modality-specific and required the activation of acid-sensing ion channel 3 (ASIC3) or transient receptor potential cation channel V1 (TRPV1). Activation of ASIC3 was associated with increased activity of tetrodotoxin (TTX)-sensitive voltage-gated sodium channels but not protein kinase Cϵ (PKCϵ) in isolectin B4 (IB4)-negative muscle nociceptors. In contrast, increased activity of TTX-resistant voltage-gated sodium channels with ASIC3 or TRPV1 activation in NaV1.8-positive muscle nociceptors was required for the development of chronic hyperalgesia. Accordingly, compared to wild type mice, NaV1.8-null mice showed briefer acid-induced hyperalgesia (5 days vs. >27 days). Conclusion ASIC3 activation may manifest a new type of nociceptor priming in IB4-negative muscle nociceptors. The activation of ASIC3 and TRPV1 as well as enhanced NaV1.8 activity are essential for the development of long-lasting hyperalgesia in acid-induced, chronic, widespread muscle pain.
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Affiliation(s)
| | | | | | | | | | | | - Chih-Cheng Chen
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan.
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