1
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Ferron L, Harding EK, Gandini MA, Brideau C, Stys PK, Zamponi GW. Functional remodeling of presynaptic voltage-gated calcium channels in superficial layers of the dorsal horn during neuropathic pain. iScience 2024; 27:109973. [PMID: 38827405 PMCID: PMC11140212 DOI: 10.1016/j.isci.2024.109973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 04/29/2024] [Accepted: 05/10/2024] [Indexed: 06/04/2024] Open
Abstract
N- and P/Q-type voltage-gated Ca2+ channels are critical for synaptic transmission. While their expression is increased in the dorsal root ganglion (DRG) neuron cell bodies during neuropathic pain conditions, less is known about their synaptic remodeling. Here, we combined genetic tools with 2-photon Ca2+ imaging to explore the functional remodeling that occurs in central presynaptic terminals of DRG neurons during neuropathic pain. We imaged GCaMP6s fluorescence responses in an ex vivo spinal cord preparation from mice expressing GCaMP6s in Trpv1-Cre lineage nociceptors. We show that Ca2+ transient amplitude is increased in central terminals of these neurons after spared nerve injury, and that this increase is mediated by both N- and P/Q-type channels. We found that GABA-B receptor-dependent inhibition of Ca2+ transients was potentiated in the superficial layer of the dorsal horn. Our results provide direct evidence toward nerve injury-induced functional remodeling of presynaptic Ca2+ channels in Trpv1-lineage nociceptor terminals.
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Affiliation(s)
- Laurent Ferron
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Calgary Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada
| | - Erika K. Harding
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Calgary Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada
| | - Maria A. Gandini
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Calgary Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada
| | - Craig Brideau
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Calgary Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada
| | - Peter K. Stys
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Calgary Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada
| | - Gerald W. Zamponi
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Calgary Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada
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2
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Cao B, Xu Q, Shi Y, Zhao R, Li H, Zheng J, Liu F, Wan Y, Wei B. Pathology of pain and its implications for therapeutic interventions. Signal Transduct Target Ther 2024; 9:155. [PMID: 38851750 PMCID: PMC11162504 DOI: 10.1038/s41392-024-01845-w] [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: 05/12/2023] [Revised: 04/08/2024] [Accepted: 04/25/2024] [Indexed: 06/10/2024] Open
Abstract
Pain is estimated to affect more than 20% of the global population, imposing incalculable health and economic burdens. Effective pain management is crucial for individuals suffering from pain. However, the current methods for pain assessment and treatment fall short of clinical needs. Benefiting from advances in neuroscience and biotechnology, the neuronal circuits and molecular mechanisms critically involved in pain modulation have been elucidated. These research achievements have incited progress in identifying new diagnostic and therapeutic targets. In this review, we first introduce fundamental knowledge about pain, setting the stage for the subsequent contents. The review next delves into the molecular mechanisms underlying pain disorders, including gene mutation, epigenetic modification, posttranslational modification, inflammasome, signaling pathways and microbiota. To better present a comprehensive view of pain research, two prominent issues, sexual dimorphism and pain comorbidities, are discussed in detail based on current findings. The status quo of pain evaluation and manipulation is summarized. A series of improved and innovative pain management strategies, such as gene therapy, monoclonal antibody, brain-computer interface and microbial intervention, are making strides towards clinical application. We highlight existing limitations and future directions for enhancing the quality of preclinical and clinical research. Efforts to decipher the complexities of pain pathology will be instrumental in translating scientific discoveries into clinical practice, thereby improving pain management from bench to bedside.
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Affiliation(s)
- Bo Cao
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China
| | - Qixuan Xu
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China
- Medical School of Chinese PLA, Beijing, 100853, China
| | - Yajiao Shi
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education/National Health Commission, Peking University, Beijing, 100191, China
| | - Ruiyang Zhao
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China
- Medical School of Chinese PLA, Beijing, 100853, China
| | - Hanghang Li
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China
- Medical School of Chinese PLA, Beijing, 100853, China
| | - Jie Zheng
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education/National Health Commission, Peking University, Beijing, 100191, China
| | - Fengyu Liu
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education/National Health Commission, Peking University, Beijing, 100191, China.
| | - You Wan
- Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education/National Health Commission, Peking University, Beijing, 100191, China.
| | - Bo Wei
- Department of General Surgery, First Medical Center, Chinese PLA General Hospital, Beijing, 100853, China.
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3
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Xie YF, Yang J, Ratté S, Prescott SA. Similar excitability through different sodium channels and implications for the analgesic efficacy of selective drugs. eLife 2024; 12:RP90960. [PMID: 38687187 PMCID: PMC11060714 DOI: 10.7554/elife.90960] [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] [Indexed: 05/02/2024] Open
Abstract
Nociceptive sensory neurons convey pain-related signals to the CNS using action potentials. Loss-of-function mutations in the voltage-gated sodium channel NaV1.7 cause insensitivity to pain (presumably by reducing nociceptor excitability) but clinical trials seeking to treat pain by inhibiting NaV1.7 pharmacologically have struggled. This may reflect the variable contribution of NaV1.7 to nociceptor excitability. Contrary to claims that NaV1.7 is necessary for nociceptors to initiate action potentials, we show that nociceptors can achieve similar excitability using different combinations of NaV1.3, NaV1.7, and NaV1.8. Selectively blocking one of those NaV subtypes reduces nociceptor excitability only if the other subtypes are weakly expressed. For example, excitability relies on NaV1.8 in acutely dissociated nociceptors but responsibility shifts to NaV1.7 and NaV1.3 by the fourth day in culture. A similar shift in NaV dependence occurs in vivo after inflammation, impacting ability of the NaV1.7-selective inhibitor PF-05089771 to reduce pain in behavioral tests. Flexible use of different NaV subtypes exemplifies degeneracy - achieving similar function using different components - and compromises reliable modulation of nociceptor excitability by subtype-selective inhibitors. Identifying the dominant NaV subtype to predict drug efficacy is not trivial. Degeneracy at the cellular level must be considered when choosing drug targets at the molecular level.
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Affiliation(s)
- Yu-Feng Xie
- Neurosciences and Mental Health, The Hospital for Sick ChildrenTorontoCanada
| | - Jane Yang
- Neurosciences and Mental Health, The Hospital for Sick ChildrenTorontoCanada
- Institute of Biomedical Engineering, University of TorontoTorontoCanada
| | - Stéphanie Ratté
- Neurosciences and Mental Health, The Hospital for Sick ChildrenTorontoCanada
| | - Steven A Prescott
- Neurosciences and Mental Health, The Hospital for Sick ChildrenTorontoCanada
- Institute of Biomedical Engineering, University of TorontoTorontoCanada
- Department of Physiology, University of TorontoTorontoCanada
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4
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Fetell M, Sendel M, Li T, Marinelli L, Vollert J, Ruggerio E, Houk G, Dockum M, Albrecht PJ, Rice FL, Baron R. Cutaneous nerve fiber and peripheral Nav1.7 assessment in a large cohort of patients with postherpetic neuralgia. Pain 2023; 164:2435-2446. [PMID: 37366590 PMCID: PMC10578423 DOI: 10.1097/j.pain.0000000000002950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 04/06/2023] [Accepted: 04/25/2023] [Indexed: 06/28/2023]
Abstract
ABSTRACT The mechanisms of pain in postherpetic neuralgia (PHN) are still unclear, with some studies showing loss of cutaneous sensory nerve fibers that seemed to correlate with pain level. We report results of skin biopsies and correlations with baseline pain scores, mechanical hyperalgesia, and the Neuropathic Pain Symptom Inventory (NPSI) in 294 patients who participated in a clinical trial of TV-45070, a topical semiselective sodium 1.7 channel (Nav1.7) blocker. Intraepidermal nerve fibers and subepidermal Nav1.7 immunolabeled fibers were quantified in skin punch biopsies from the area of maximal PHN pain, as well as from the contralateral, homologous (mirror image) region. Across the entire study population, a 20% reduction in nerve fibers on the PHN-affected side compared with that in the contralateral side was noted; however, the reduction was much higher in older individuals, approaching 40% in those aged 70 years or older. There was a decrease in contralateral fiber counts as well, also noted in prior biopsy studies, the mechanism of which is not fully clear. Nav1.7-positive immunolabeling was present in approximately one-third of subepidermal nerve fibers and did not differ on the PHN-affected vs contralateral sides. Using cluster analysis, 2 groups could be identified, with the first cluster showing higher baseline pain, higher NPSI scores for squeezing and cold-induced pain, higher nerve fiber density, and higher Nav1.7 expression. While Nav1.7 varies from patient to patient, it does not seem to be a key pathophysiological driver of PHN pain. Individual differences in Nav1.7 expression, however, may determine the intensity and sensory aspects of pain.
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Affiliation(s)
| | - Manon Sendel
- Division of Neurological Pain Research and Therapy, Department of Neurology, University Hospital of Schleswig-Holstein, Campus Kiel, Germany
| | - Thomas Li
- Teva Pharmaceuticals, West Chester, PA, United States
| | | | - Jan Vollert
- Division of Neurological Pain Research and Therapy, Department of Neurology, University Hospital of Schleswig-Holstein, Campus Kiel, Germany
- Pain Research, MSk Lab, Department of Surgery and Cancer, Imperial College, London, United Kingdom
- Department of Neurophysiology, Mannheim Center for Translational Neuroscience MCTN, Medical Faculty Mannheim, Ruprecht Karls University, Heidelberg, Germany
- Department of Anaesthesiology, Intensive Care and Pain Medicine, University Hospital Muenster, Muenster, Germany
| | | | - George Houk
- Integrated Tissue Dynamics LLC, Rensselaer, NY, United States
| | - Marilyn Dockum
- Integrated Tissue Dynamics LLC, Rensselaer, NY, United States
| | | | - Frank L. Rice
- Integrated Tissue Dynamics LLC, Rensselaer, NY, United States
| | - Ralf Baron
- Division of Neurological Pain Research and Therapy, Department of Neurology, University Hospital of Schleswig-Holstein, Campus Kiel, Germany
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5
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Loose S, Lischka A, Kuehs S, Nau C, Heinemann SH, Kurth I, Leipold E. Peripheral temperature dysregulation associated with functionally altered Na V1.8 channels. Pflugers Arch 2023; 475:1343-1355. [PMID: 37695396 PMCID: PMC10567936 DOI: 10.1007/s00424-023-02856-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 08/23/2023] [Accepted: 09/01/2023] [Indexed: 09/12/2023]
Abstract
The voltage-gated sodium channel NaV1.8 is prominently expressed in the soma and axons of small-caliber sensory neurons, and pathogenic variants of the corresponding gene SCN10A are associated with peripheral pain and autonomic dysfunction. While most disease-associated SCN10A variants confer gain-of-function properties to NaV1.8, resulting in hyperexcitability of sensory neurons, a few affect afferent excitability through a loss-of-function mechanism. Using whole-exome sequencing, we here identify a rare heterozygous SCN10A missense variant resulting in alteration p.V1287I in NaV1.8 in a patient with a 15-year history of progressively worsening temperature dysregulation in the distal extremities, particularly in the feet. Further symptoms include increasingly intensifying tingling and numbness in the fingers and increased sweating. To assess the impact of p.V1287I on channel function, we performed voltage-clamp recordings demonstrating that the alteration confers loss- and gain-of-function characteristics to NaV1.8 characterized by a right-shifted voltage dependence of channel activation and inactivation. Current-clamp recordings from transfected mouse dorsal root ganglion neurons further revealed that NaV1.8-V1287I channels broaden the action potentials of sensory neurons and increase their firing rates in response to depolarizing current stimulations, indicating a gain-of-function mechanism of the variant at the cellular level in a heterozygous setting. The data support the hypothesis that the properties of NaV1.8 p.V1287I are causative for the patient's symptoms and that nonpainful peripheral paresthesias should be considered part of the clinical spectrum of NaV1.8-associated disorders.
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Affiliation(s)
- Simon Loose
- Department of Anesthesiology and Intensive Care & CBBM - Center of Brain, Behavior and Metabolism, University of Luebeck, Ratzeburger Allee 160, 23562, Luebeck, Germany
| | - Annette Lischka
- Institute for Human Genetics and Genomic Medicine, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Samuel Kuehs
- Department of Anesthesiology and Intensive Care & CBBM - Center of Brain, Behavior and Metabolism, University of Luebeck, Ratzeburger Allee 160, 23562, Luebeck, Germany
| | - Carla Nau
- Department of Anesthesiology and Intensive Care & CBBM - Center of Brain, Behavior and Metabolism, University of Luebeck, Ratzeburger Allee 160, 23562, Luebeck, Germany
| | - Stefan H Heinemann
- Center for Molecular Biomedicine, Department of Biophysics, Friedrich Schiller University Jena and Jena University Hospital, Jena, Germany
| | - Ingo Kurth
- Institute for Human Genetics and Genomic Medicine, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Enrico Leipold
- Department of Anesthesiology and Intensive Care & CBBM - Center of Brain, Behavior and Metabolism, University of Luebeck, Ratzeburger Allee 160, 23562, Luebeck, Germany.
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6
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Fuller AM, Luiz A, Tian N, Arcangeletti M, Iseppon F, Sexton JE, Millet Q, Caxaria S, Ketabi N, Celik P, Wood JN, Sikandar S. Gate control of sensory neurotransmission in peripheral ganglia by proprioceptive sensory neurons. Brain 2023; 146:4033-4039. [PMID: 37249190 PMCID: PMC10549771 DOI: 10.1093/brain/awad182] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 04/12/2023] [Accepted: 05/18/2023] [Indexed: 05/31/2023] Open
Abstract
Melzak and Wall's gate control theory proposed that innocuous input into the dorsal horn of the spinal cord represses pain-inducing nociceptive input. Here we show that input from proprioceptive parvalbumin-expressing sensory neurons tonically represses nociceptor activation within dorsal root ganglia. Deletion of parvalbumin-positive sensory neurons leads to enhanced nociceptor activity measured with GCaMP3, increased input into wide dynamic range neurons of the spinal cord and increased acute and spontaneous pain behaviour, as well as potentiated innocuous sensation. Parvalbumin-positive sensory neurons express the enzymes and transporters necessary to produce vesicular GABA that is known to be released from depolarized somata. These observations support the view that gate control mechanisms occur peripherally within dorsal root ganglia.
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Affiliation(s)
- Alice M Fuller
- William Harvey Research Institute, Queen Mary University of London, London EC1M 6BQ, UK
- Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Ana Luiz
- Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Naxi Tian
- Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Manuel Arcangeletti
- Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Federico Iseppon
- Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Jane E Sexton
- Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Queensta Millet
- Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Sara Caxaria
- William Harvey Research Institute, Queen Mary University of London, London EC1M 6BQ, UK
| | - Niloofar Ketabi
- William Harvey Research Institute, Queen Mary University of London, London EC1M 6BQ, UK
| | - Petek Celik
- William Harvey Research Institute, Queen Mary University of London, London EC1M 6BQ, UK
| | - John N Wood
- Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Shafaq Sikandar
- William Harvey Research Institute, Queen Mary University of London, London EC1M 6BQ, UK
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7
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Pocratsky AM, Sleigh JN. Intraperitoneal Injection of Neonatal Mice. Bio Protoc 2023; 13:e4826. [PMID: 37753468 PMCID: PMC10518777 DOI: 10.21769/bioprotoc.4826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 07/27/2023] [Accepted: 07/27/2023] [Indexed: 09/28/2023] Open
Abstract
Administration of substances into neonatal mice is required for early treatment with pre-clinical therapeutics, delivery of recombination-inducing substances, and dosing with viruses or toxins, amongst other things. Several injection routes into mouse pups are possible, including intravenous and intracerebroventricular, each with their own advantages and limitations. Here, we describe a simple and rapid protocol for the intraperitoneal injection of neonatal mice for systemic dosing. By detaching a 30-gauge needle from its plastic hub and inserting it into polyethylene tubing attached to a Hamilton syringe, small volumes (1-10 μL) can be accurately injected into the peritoneal cavity of pups aged 1-5 days old. The procedure can be completed within a few minutes, is generally safe and well tolerated by both pups and parents, and can be used in combination with alternative administration routes. Key features • This protocol provides a simple description to rapidly and efficiently inject mouse pups aged 1-5 days for systemic dosing. • Allows treatment of neonatal mice with substances such as viruses and compounds for research across disciplines.
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Affiliation(s)
- Amanda M. Pocratsky
- Department of Neuromuscular Diseases and UCL Queen Square Motor Neuron Disease Centre, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - James N. Sleigh
- Department of Neuromuscular Diseases and UCL Queen Square Motor Neuron Disease Centre, UCL Queen Square Institute of Neurology, University College London, London, UK
- UK Dementia Research Institute, University College London, London, UK
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8
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Pacifico P, Coy-Dibley JS, Miller RJ, Menichella DM. Peripheral mechanisms of peripheral neuropathic pain. Front Mol Neurosci 2023; 16:1252442. [PMID: 37781093 PMCID: PMC10537945 DOI: 10.3389/fnmol.2023.1252442] [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: 07/03/2023] [Accepted: 08/14/2023] [Indexed: 10/03/2023] Open
Abstract
Peripheral neuropathic pain (PNP), neuropathic pain that arises from a damage or disease affecting the peripheral nervous system, is associated with an extremely large disease burden, and there is an increasing and urgent need for new therapies for treating this disorder. In this review we have highlighted therapeutic targets that may be translated into disease modifying therapies for PNP associated with peripheral neuropathy. We have also discussed how genetic studies and novel technologies, such as optogenetics, chemogenetics and single-cell RNA-sequencing, have been increasingly successful in revealing novel mechanisms underlying PNP. Additionally, consideration of the role of non-neuronal cells and communication between the skin and sensory afferents is presented to highlight the potential use of drug treatment that could be applied topically, bypassing drug side effects. We conclude by discussing the current difficulties to the development of effective new therapies and, most importantly, how we might improve the translation of targets for peripheral neuropathic pain identified from studies in animal models to the clinic.
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Affiliation(s)
- Paola Pacifico
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - James S. Coy-Dibley
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Richard J. Miller
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Daniela M. Menichella
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
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9
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Deng L, Dourado M, Reese RM, Huang K, Shields SD, Stark KL, Maksymetz J, Lin H, Kaminker JS, Jung M, Foreman O, Tao J, Ngu H, Joseph V, Roose-Girma M, Tam L, Lardell S, Orrhult LS, Karila P, Allard J, Hackos DH. Nav1.7 is essential for nociceptor action potentials in the mouse in a manner independent of endogenous opioids. Neuron 2023; 111:2642-2659.e13. [PMID: 37352856 DOI: 10.1016/j.neuron.2023.05.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 04/07/2023] [Accepted: 05/26/2023] [Indexed: 06/25/2023]
Abstract
Loss-of-function mutations in Nav1.7, a voltage-gated sodium channel, cause congenital insensitivity to pain (CIP) in humans, demonstrating that Nav1.7 is essential for the perception of pain. However, the mechanism by which loss of Nav1.7 results in insensitivity to pain is not entirely clear. It has been suggested that loss of Nav1.7 induces overexpression of enkephalin, an endogenous opioid receptor agonist, leading to opioid-dependent analgesia. Using behavioral pharmacology and single-cell RNA-seq analysis, we find that overexpression of enkephalin occurs only in cLTMR neurons, a subclass of sensory neurons involved in low-threshold touch detection, and that this overexpression does not play a role in the analgesia observed following genetic removal of Nav1.7. Furthermore, we demonstrate using laser speckle contrast imaging (LSCI) and in vivo electrophysiology that Nav1.7 function is required for the initiation of C-fiber action potentials (APs), which explains the observed insensitivity to pain following genetic removal or inhibition of Nav1.7.
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Affiliation(s)
- Lunbin Deng
- Department of Neuroscience, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA
| | - Michelle Dourado
- Department of Neuroscience, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA
| | - Rebecca M Reese
- Department of Neuroscience, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA
| | - Kevin Huang
- Department of OMNI Bioinformatics, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA
| | - Shannon D Shields
- Department of Neuroscience, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA
| | - Kimberly L Stark
- Department of Neuroscience, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA
| | - James Maksymetz
- Department of Neuroscience, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA
| | - Han Lin
- Department of Neuroscience, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA
| | - Joshua S Kaminker
- Department of OMNI Bioinformatics, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA
| | - Min Jung
- Department of OMNI Bioinformatics, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA
| | - Oded Foreman
- Department of Pathology, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA
| | - Janet Tao
- Department of Pathology, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA
| | - Hai Ngu
- Department of Pathology, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA
| | - Victory Joseph
- Department of Biomedical Imaging, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA
| | - Meron Roose-Girma
- Department of Molecular Biology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Lucinda Tam
- Department of Molecular Biology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | | | | | - Paul Karila
- Cellectricon AB, Neongatan 4B, 431 53 Mölndal, Sweden
| | - Julien Allard
- E-Phys, CRBC, 28 place Henri Dunant, 63000 Clermont-Ferrand, France.
| | - David H Hackos
- Department of Neuroscience, Genentech, Inc., 1 DNA Way, South San Francisco, CA, USA.
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10
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Haroun R, Gossage SJ, Luiz AP, Arcangeletti M, Sikandar S, Zhao J, Cox JJ, Wood JN. Chemogenetic Silencing of Na V1.8-Positive Sensory Neurons Reverses Chronic Neuropathic and Bone Cancer Pain in FLEx PSAM 4-GlyR Mice. eNeuro 2023; 10:ENEURO.0151-23.2023. [PMID: 37679042 PMCID: PMC10523839 DOI: 10.1523/eneuro.0151-23.2023] [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: 05/10/2023] [Revised: 08/15/2023] [Accepted: 08/23/2023] [Indexed: 09/09/2023] Open
Abstract
Drive from peripheral neurons is essential in almost all pain states, but pharmacological silencing of these neurons to effect analgesia has proved problematic. Reversible gene therapy using long-lived chemogenetic approaches is an appealing option. We used the genetically activated chloride channel PSAM4-GlyR to examine pain pathways in mice. Using recombinant AAV9-based delivery to sensory neurons, we found a reversal of acute pain behavior and diminished neuronal activity using in vitro and in vivo GCaMP imaging on activation of PSAM4-GlyR with varenicline. A significant reduction in inflammatory heat hyperalgesia and oxaliplatin-induced cold allodynia was also observed. Importantly, there was no impairment of motor coordination, but innocuous von Frey sensation was inhibited. We generated a transgenic mouse that expresses a CAG-driven FLExed PSAM4-GlyR downstream of the Rosa26 locus that requires Cre recombinase to enable the expression of PSAM4-GlyR and tdTomato. We used NaV1.8 Cre to examine the role of predominantly nociceptive NaV1.8+ neurons in cancer-induced bone pain (CIBP) and neuropathic pain caused by chronic constriction injury (CCI). Varenicline activation of PSAM4-GlyR in NaV1.8-positive neurons reversed CCI-driven mechanical, thermal, and cold sensitivity. Additionally, varenicline treatment of mice with CIBP expressing PSAM4-GlyR in NaV1.8+ sensory neurons reversed cancer pain as assessed by weight-bearing. Moreover, when these mice were subjected to acute pain assays, an elevation in withdrawal thresholds to noxious mechanical and thermal stimuli was detected, but innocuous mechanical sensations remained unaffected. These studies confirm the utility of PSAM4-GlyR chemogenetic silencing in chronic pain states for mechanistic analysis and potential future therapeutic use.
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Affiliation(s)
- Rayan Haroun
- Wolfson Institute for Biomedical Research, Division of Medicine, University College London, London WC1E 6BT, United Kingdom
| | - Samuel J Gossage
- Wolfson Institute for Biomedical Research, Division of Medicine, University College London, London WC1E 6BT, United Kingdom
| | - Ana Paula Luiz
- Wolfson Institute for Biomedical Research, Division of Medicine, University College London, London WC1E 6BT, United Kingdom
| | - Manuel Arcangeletti
- Wolfson Institute for Biomedical Research, Division of Medicine, University College London, London WC1E 6BT, United Kingdom
| | - Shafaq Sikandar
- William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Jing Zhao
- Wolfson Institute for Biomedical Research, Division of Medicine, University College London, London WC1E 6BT, United Kingdom
| | - James J Cox
- Wolfson Institute for Biomedical Research, Division of Medicine, University College London, London WC1E 6BT, United Kingdom
| | - John N Wood
- Wolfson Institute for Biomedical Research, Division of Medicine, University College London, London WC1E 6BT, United Kingdom
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11
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Fabbri R, Spennato D, Conte G, Konstantoulaki A, Lazzarini C, Saracino E, Nicchia GP, Frigeri A, Zamboni R, Spray DC, Benfenati V. The emerging science of Glioception: Contribution of glia in sensing, transduction, circuit integration of interoception. Pharmacol Ther 2023; 245:108403. [PMID: 37024060 DOI: 10.1016/j.pharmthera.2023.108403] [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: 10/13/2022] [Revised: 03/29/2023] [Accepted: 03/30/2023] [Indexed: 04/08/2023]
Abstract
Interoception is the process by which the nervous system regulates internal functions to achieve homeostasis. The role of neurons in interoception has received considerable recent attention, but glial cells also contribute. Glial cells can sense and transduce signals including osmotic, chemical, and mechanical status of extracellular milieu. Their ability to dynamically communicate "listening" and "talking" to neurons is necessary to monitor and regulate homeostasis and information integration in the nervous system. This review introduces the concept of "Glioception" and focuses on the process by which glial cells sense, interpret and integrate information about the inner state of the organism. Glial cells are ideally positioned to act as sensors and integrators of diverse interoceptive signals and can trigger regulatory responses via modulation of the activity of neuronal networks, both in physiological and pathological conditions. We believe that understanding and manipulating glioceptive processes and underlying molecular mechanisms provide a key path to develop new therapies for the prevention and alleviation of devastating interoceptive dysfunctions, among which pain is emphasized here with more focused details.
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Affiliation(s)
- Roberta Fabbri
- Institute for Organic Synthesis and Photoreactivity (ISOF), National Research Council of Italy (CNR), Via P. Gobetti 101, I-40129 Bologna, Italy; Department of Electrical, Electronic, and Information Engineering "Guglielmo Marconi", University of Bologna, viale del Risorgimento 2, 40136 Bologna, Italy.
| | - Diletta Spennato
- Institute for Organic Synthesis and Photoreactivity (ISOF), National Research Council of Italy (CNR), Via P. Gobetti 101, I-40129 Bologna, Italy; Department of Bioscience, Biotechnologies and Biopharmaceutics, Centre of Excellence in Comparative Genomics, University of Bari "Aldo Moro", Bari, BA, Italy
| | - Giorgia Conte
- Institute for Organic Synthesis and Photoreactivity (ISOF), National Research Council of Italy (CNR), Via P. Gobetti 101, I-40129 Bologna, Italy
| | - Aikaterini Konstantoulaki
- Institute for Organic Synthesis and Photoreactivity (ISOF), National Research Council of Italy (CNR), Via P. Gobetti 101, I-40129 Bologna, Italy; Department of Chemistry "Giacomo Ciamician", University of Bologna, Via Selmi, 2, 40126 Bologna, BO, Italy
| | - Chiara Lazzarini
- Institute for Organic Synthesis and Photoreactivity (ISOF), National Research Council of Italy (CNR), Via P. Gobetti 101, I-40129 Bologna, Italy
| | - Emanuela Saracino
- Institute for Organic Synthesis and Photoreactivity (ISOF), National Research Council of Italy (CNR), Via P. Gobetti 101, I-40129 Bologna, Italy
| | - Grazia Paola Nicchia
- School of Medicine, Basic Medical Sciences, Neuroscience and Sense Organs, University of Bari "Aldo Moro", Bari, BA, Italy; Department of Bioscience, Biotechnologies and Biopharmaceutics, Centre of Excellence in Comparative Genomics, University of Bari "Aldo Moro", Bari, BA, Italy
| | - Antonio Frigeri
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA; Department of Bioscience, Biotechnologies and Biopharmaceutics, Centre of Excellence in Comparative Genomics, University of Bari "Aldo Moro", Bari, BA, Italy
| | - Roberto Zamboni
- Institute for Organic Synthesis and Photoreactivity (ISOF), National Research Council of Italy (CNR), Via P. Gobetti 101, I-40129 Bologna, Italy
| | - David C Spray
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | - Valentina Benfenati
- Institute for Organic Synthesis and Photoreactivity (ISOF), National Research Council of Italy (CNR), Via P. Gobetti 101, I-40129 Bologna, Italy.
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12
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Bodnar RJ. Endogenous opiates and behavior: 2021. Peptides 2023; 164:171004. [PMID: 36990387 DOI: 10.1016/j.peptides.2023.171004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 03/23/2023] [Accepted: 03/23/2023] [Indexed: 03/29/2023]
Abstract
This paper is the forty-fourth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2021 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonizts and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, CUNY, 65-30 Kissena Blvd., Flushing, NY 11367, USA.
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13
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Shiers S, Funk G, Cervantes A, Horton P, Dussor G, Hennen S, Price TJ. Na V1.7 mRNA and protein expression in putative projection neurons of the human spinal dorsal horn. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.04.527110. [PMID: 36778234 PMCID: PMC9915702 DOI: 10.1101/2023.02.04.527110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
NaV1.7, a membrane-bound voltage-gated sodium channel, is preferentially expressed along primary sensory neurons, including their peripheral & central nerve endings, axons, and soma within the dorsal root ganglia and plays an integral role in amplifying membrane depolarization and pain neurotransmission. Loss- and gain-of-function mutations in the gene encoding NaV1.7, SCN9A, are associated with a complete loss of pain sensation or exacerbated pain in humans, respectively. As an enticing pain target supported by human genetic validation, many compounds have been developed to inhibit NaV1.7 but have disappointed in clinical trials. The underlying reasons are still unclear, but recent reports suggest that inhibiting NaV1.7 in central terminals of nociceptor afferents is critical for achieving pain relief by pharmacological inhibition of NaV1.7. We report for the first time that NaV1.7 mRNA is expressed in putative projection neurons (NK1R+) in the human spinal dorsal horn, predominantly in lamina 1 and 2, as well as in deep dorsal horn neurons and motor neurons in the ventral horn. NaV1.7 protein was found in the central axons of sensory neurons terminating in lamina 1-2, but also was detected in the axon initial segment of resident spinal dorsal horn neurons and in axons entering the anterior commissure. Given that projection neurons are critical for conveying nociceptive information from the dorsal horn to the brain, these data support that dorsal horn NaV1.7 expression may play an unappreciated role in pain phenotypes observed in humans with genetic SCN9A mutations, and in achieving analgesic efficacy in clinical trials.
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Affiliation(s)
- Stephanie Shiers
- University of Texas at Dallas, School of Behavioral and Brain Sciences and Center for Advanced Pain Studies
| | | | | | | | - Gregory Dussor
- University of Texas at Dallas, School of Behavioral and Brain Sciences and Center for Advanced Pain Studies
| | | | - Theodore J. Price
- University of Texas at Dallas, School of Behavioral and Brain Sciences and Center for Advanced Pain Studies
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14
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Gutierrez‐Quintana R, Christen M, Faller KME, Guevar J, Jagannathan V, Leeb T. SCN9A variant in a family of mixed breed dogs with congenital insensitivity to pain. J Vet Intern Med 2023; 37:230-235. [PMID: 36630088 PMCID: PMC9889608 DOI: 10.1111/jvim.16610] [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: 09/26/2022] [Accepted: 12/08/2022] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Congenital insensitivity to pain (CIP) and hereditary sensory and autonomic neuropathies (HSANs) are a rare group of genetic disorders causing inability to feel pain. Three different associated variants have been identified in dogs: 1 in Border Collies, 1 in mixed breed dogs, and 1 in Spaniels and Pointers. OBJECTIVES To clinically and genetically characterize CIP in a family of mixed breed dogs. ANIMALS Two mixed breed dogs from the same litter were independently presented: 1 for evaluation of painless fractures, and the other for chronic thermal skin injuries. METHODS Physical, neurological, and histopathological evaluations were performed. Whole genome sequencing of 1 affected dog was used to identify homozygous protein-changing variants that were not present in 926 control genomes from diverse dog breeds. RESULTS Physical and neurological examinations showed the absence of superficial and deep pain perception in the entire body. Histopathological evaluations of the brain, spinal cord and sensory ganglia were normal. Whole genome sequencing identified a homozygous missense variant in SCN9A, XM_038584713.1:c.2761C>T or XP_038440641.1:(p.Arg921Cys). Both affected dogs were homozygous for the mutant allele, which was not detected in 926 dogs of different breeds. CONCLUSIONS AND CLINICAL IMPORTANCE We confirmed the diagnosis of CIP in a family of mixed breed dogs and identified a likely pathogenic variant in the SCN9A gene. The clinical signs observed in these dogs mimic those reported in humans with pathogenic SCN9A variants causing CIP. This report is the first of a spontaneous pathogenic SCN9A variant in domestic animals.
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Affiliation(s)
- Rodrigo Gutierrez‐Quintana
- Small Animal Hospital, School of Biodiversity, One Health and Veterinary MedicineUniversity of GlasgowGlasgowUK
| | - Matthias Christen
- Institute of Genetics, Vetsuisse FacultyUniversity of BernBernSwitzerland
| | - Kiterie M. E. Faller
- Royal (Dick) School of Veterinary StudiesThe University of EdinburghMidlothianUK
| | - Julien Guevar
- Department of Clinical Veterinary Sciences, Vetsuisse FacultyUniversity of BernBernSwitzerland
| | - Vidhya Jagannathan
- Institute of Genetics, Vetsuisse FacultyUniversity of BernBernSwitzerland
| | - Tosso Leeb
- Institute of Genetics, Vetsuisse FacultyUniversity of BernBernSwitzerland
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15
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Maximizing treatment efficacy through patient stratification in neuropathic pain trials. Nat Rev Neurol 2023; 19:53-64. [PMID: 36400867 DOI: 10.1038/s41582-022-00741-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2022] [Indexed: 11/19/2022]
Abstract
Treatment of neuropathic pain remains inadequate despite the elucidation of multiple pathophysiological mechanisms and the development of promising therapeutic compounds. The lack of success in translating knowledge into clinical practice has discouraged pharmaceutical companies from investing in pain medicine; however, new patient stratification approaches could help bridge the translation gap and develop individualized therapeutic approaches. As we highlight in this article, subgrouping of patients according to sensory profiles and other baseline characteristics could aid the prediction of treatment success. Furthermore, novel outcome measures have been developed for patients with neuropathic pain. The extent to which sensory profiles and outcome measures can be employed in routine clinical practice and clinical trials and across distinct neuropathic pain aetiologies is yet to be determined. Improvements in animal models, drawing on our knowledge of human pain, and robust public-private partnerships will be needed to pave the way to innovative and effective pain medicine in the future.
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16
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Na V1.7 Channel Blocker [Ala 5, Phe 6, Leu 26, Arg 28]GpTx-1 Attenuates CFA-induced Inflammatory Hypersensitivity in Rats via Endogenous Enkephalin Mechanism. THE JOURNAL OF PAIN 2022; 24:840-859. [PMID: 36586660 DOI: 10.1016/j.jpain.2022.12.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 12/17/2022] [Accepted: 12/21/2022] [Indexed: 12/30/2022]
Abstract
Venom-derived NaV1.7 channel blockers have promising prospects in pain management. The 34-residue tarantula peptide GpTx-1 is a potent NaV1.7 channel blocker. Its powerful analog [Ala5, Phe6, Leu26, Arg28]GpTx-1 (GpTx-1-71) displayed excellent NaV1.7 selectivity and analgesic properties in mice. The current study aimed to elucidate the anti-hyperalgesic activities of GpTx-1-71 in inflammatory pain and reveal the underlying mechanisms. Our results demonstrated that intrathecal and intraplantar injections of GpTx-1-71 dose-dependently attenuated CFA-induced inflammatory hypersensitivity in rats. Moreover, GpTx-1-71-induced anti-hyperalgesia was significantly reduced by opioid receptor antagonists and the enkephalin antibody and diminished in proenkephalin (Penk) gene knockout animals. Consistently, GpTx-1-71 treatment increased the enkephalin level in the spinal dorsal horn and promoted the Penk transcription and enkephalin release in primary dorsal root ganglion (DRG) neurons, wherein sodium played a crucial role in these processes. Mass spectrometry analysis revealed that GpTx-1-71 mainly promoted the secretion of Met-enkephalin but not Leu-enkephalin from DRG neurons. In addition, the combination of subtherapeutic Met-enkephalin and GpTx-1-71 produced synergistic anti-hyperalgesia in CFA-induced inflammatory hypersensitivity. These findings suggest that the endogenous enkephalin pathway is essential for GpTx-1-71-induced spinal and peripheral analgesia in inflammatory pain. PERSPECTIVE: This article presents a possible pharmacological mechanism underlying NaV1.7 blocker-induced analgesia in inflammatory pain, which helps us to better understand and develop venom-based painkillers for incurable pain.
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17
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Research progress on the mechanism of chronic neuropathic pain. IBRO Neurosci Rep 2022; 14:80-85. [PMID: 36632243 PMCID: PMC9827377 DOI: 10.1016/j.ibneur.2022.12.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Accepted: 12/17/2022] [Indexed: 12/24/2022] Open
Abstract
Chronic neuropathic pain (CNP) refers to pain that lasts for more than three months due to a disease or an injury to the somatosensory nervous system. The incidence of CNP has been increasing in the world, causing it to become a global concern and patients often experience spontaneous pain, hyperalgesia, abnormal pain or even abnormal sensation as some of its main symptoms. In addition to serious pain and poor physical health, CNP also negatively affects patients' mental health, thus impacting the overall quality of their lives. The pathogenesis of CNP is not clear, but some studies have proved that central sensitization, peripheral sensitization, neuroinflammation, dysfunction in descending nociceptive modulatory systems, oxidative stress reaction, activation of glial cells and psychological factors play an important role in the occurrence and development of CNP. In this context, this article summarizes the current research progress on the mechanism of CNP to provide a basis for further research in preventing and treating the disease.
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18
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Pathophysiology of Nociception and Rare Genetic Disorders with Increased Pain Threshold or Pain Insensitivity. PATHOPHYSIOLOGY 2022; 29:435-452. [PMID: 35997391 PMCID: PMC9397076 DOI: 10.3390/pathophysiology29030035] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 07/31/2022] [Accepted: 08/01/2022] [Indexed: 11/16/2022] Open
Abstract
Pain and nociception are different phenomena. Nociception is the result of complex activity in sensory pathways. On the other hand, pain is the effect of interactions between nociceptive processes, and cognition, emotions, as well as the social context of the individual. Alterations in the nociceptive route can have different genesis and affect the entire sensorial process. Genetic problems in nociception, clinically characterized by reduced or absent pain sensitivity, compose an important chapter within pain medicine. This chapter encompasses a wide range of very rare diseases. Several genes have been identified. These genes encode the Nav channels 1.7 and 1.9 (SCN9A, and SCN11A genes, respectively), NGFβ and its receptor tyrosine receptor kinase A, as well as the transcription factor PRDM12, and autophagy controllers (TECPR2). Monogenic disorders provoke hereditary sensory and autonomic neuropathies. Their clinical pictures are extremely variable, and a precise classification has yet to be established. Additionally, pain insensitivity is described in diverse numerical and structural chromosomal abnormalities, such as Angelman syndrome, Prader Willy syndrome, Chromosome 15q duplication syndrome, and Chromosome 4 interstitial deletion. Studying these conditions could be a practical strategy to better understand the mechanisms of nociception and investigate potential therapeutic targets against pain.
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19
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Goodwin G, McMurray S, Stevens EB, Denk F, McMahon SB. Examination of the contribution of Nav1.7 to axonal propagation in nociceptors. Pain 2022; 163:e869-e881. [PMID: 34561392 DOI: 10.1097/j.pain.0000000000002490] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 09/09/2021] [Indexed: 11/25/2022]
Abstract
ABSTRACT Nav1.7 is a promising drug target for the treatment of pain. However, there is a mismatch between the analgesia produced by Nav1.7 loss-of-function and the peripherally restricted Nav1.7 inhibitors, which may reflect a lack of understanding of the function of Nav1.7 in the transmission of nociceptive information. In the periphery, the role of Nav1.7 in transduction at nociceptive peripheral terminals has been comprehensively examined, but its role in axonal propagation in these neurons is less clearly defined. In this study, we examined the contribution of Nav1.7 to axonal propagation in nociceptors using sodium channel blockers in in vivo electrophysiological and calcium imaging recordings in mice. Using the sodium channel blocker tetrodotoxin (TTX) (1-10 µM) to inhibit Nav1.7 and other tetrodotoxin-sensitive sodium channels along the sciatic nerve, we first showed that around two-thirds of nociceptive L4 dorsal root ganglion neurons innervating the skin, but a lower proportion innervating the muscle (45%), are blocked by TTX. By contrast, nearly all large-sized cutaneous afferents (95%-100%) were blocked by axonal TTX. Many cutaneous nociceptors resistant to TTX were polymodal (57%) and capsaicin sensitive (57%). Next, we applied PF-05198007 (300 nM-1 µM) to the sciatic nerve between stimulating and recording sites to selectively block axonal Nav1.7 channels. One hundred to three hundred nanomolar PF-05198007 blocked propagation in 63% of C-fiber sensory neurons, whereas similar concentrations produced minimal block (5%) in rapidly conducting A-fiber neurons. We conclude that Nav1.7 is essential for axonal propagation in around two-thirds of nociceptive cutaneous C-fiber neurons and a lower proportion (≤45%) of nociceptive neurons innervating muscle.
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Affiliation(s)
- George Goodwin
- Neurorestoration Group, Wolfson Centre for Age-Related Diseases, King's College London, United Kingdom
| | | | | | - Franziska Denk
- Neurorestoration Group, Wolfson Centre for Age-Related Diseases, King's College London, United Kingdom
| | - Stephen B McMahon
- Neurorestoration Group, Wolfson Centre for Age-Related Diseases, King's College London, United Kingdom
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20
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A Drug Discovery Approach for an Effective Pain Therapy through Selective Inhibition of Nav1.7. Int J Mol Sci 2022; 23:ijms23126793. [PMID: 35743236 PMCID: PMC9223482 DOI: 10.3390/ijms23126793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 06/14/2022] [Accepted: 06/16/2022] [Indexed: 12/10/2022] Open
Abstract
Chronic pain is a widespread disorder affecting millions of people and is insufficiently addressed by current classes of analgesics due to significant long-term or high dosage side effects. A promising approach that was recently proposed involves the systemic inhibition of the voltage-gated sodium channel Nav1.7, capable of cancelling pain perception completely. Notwithstanding numerous attempts, currently no drugs have been approved for the inhibition of Nav1.7. The task is complicated by the difficulty of creating a selective drug for Nav1.7, and avoiding binding to the many human paralogs performing fundamental physiological functions. In our work, we obtained a promising set of ligands with up to 5-40-fold selectivity and reaching 5.2 nanomolar binding affinity by employing a proper treatment of the problem and an innovative differential in silico screening procedure to discriminate for affinity and selectivity against the Nav paralogs. The absorption, distribution, metabolism, and excretion (ADME) properties of our top-scoring ligands were also evaluated, with good to excellent results. Additionally, our study revealed that the top-scoring ligand is a stereoisomer of an already-approved drug. These facts could reduce the time required to bring a new effective and selective Nav1.7 inhibitor to the market.
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21
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Lischka A, Lassuthova P, Çakar A, Record CJ, Van Lent J, Baets J, Dohrn MF, Senderek J, Lampert A, Bennett DL, Wood JN, Timmerman V, Hornemann T, Auer-Grumbach M, Parman Y, Hübner CA, Elbracht M, Eggermann K, Geoffrey Woods C, Cox JJ, Reilly MM, Kurth I. Genetic pain loss disorders. Nat Rev Dis Primers 2022; 8:41. [PMID: 35710757 DOI: 10.1038/s41572-022-00365-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/10/2022] [Indexed: 01/05/2023]
Abstract
Genetic pain loss includes congenital insensitivity to pain (CIP), hereditary sensory neuropathies and, if autonomic nerves are involved, hereditary sensory and autonomic neuropathy (HSAN). This heterogeneous group of disorders highlights the essential role of nociception in protecting against tissue damage. Patients with genetic pain loss have recurrent injuries, burns and poorly healing wounds as disease hallmarks. CIP and HSAN are caused by pathogenic genetic variants in >20 genes that lead to developmental defects, neurodegeneration or altered neuronal excitability of peripheral damage-sensing neurons. These genetic variants lead to hyperactivity of sodium channels, disturbed haem metabolism, altered clathrin-mediated transport and impaired gene regulatory mechanisms affecting epigenetic marks, long non-coding RNAs and repetitive elements. Therapies for pain loss disorders are mainly symptomatic but the first targeted therapies are being tested. Conversely, chronic pain remains one of the greatest unresolved medical challenges, and the genes and mechanisms associated with pain loss offer new targets for analgesics. Given the progress that has been made, the coming years are promising both in terms of targeted treatments for pain loss disorders and the development of innovative pain medicines based on knowledge of these genetic diseases.
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Affiliation(s)
- Annette Lischka
- Institute of Human Genetics, Medical Faculty, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Petra Lassuthova
- Department of Paediatric Neurology, 2nd Faculty of Medicine, Charles University in Prague and Motol University Hospital, Prague, Czech Republic
| | - Arman Çakar
- Neuromuscular Unit, Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Christopher J Record
- Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
| | - Jonas Van Lent
- Peripheral Neuropathy Research Group, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium.,Laboratory of Neuromuscular Pathology, Institute Born Bunge, Antwerp, Belgium
| | - Jonathan Baets
- Laboratory of Neuromuscular Pathology, Institute Born Bunge, Antwerp, Belgium.,Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.,Neuromuscular Reference Centre, Department of Neurology, Antwerp University Hospital, Antwerp, Belgium
| | - Maike F Dohrn
- Department of Neurology, Medical Faculty, Uniklinik RWTH Aachen University, Aachen, Germany.,Dr. John T. Macdonald Foundation, Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Jan Senderek
- Friedrich-Baur-Institute, Department of Neurology, Ludwig-Maximilians-University, Munich, Germany
| | - Angelika Lampert
- Institute of Physiology, Medical Faculty, Uniklinik RWTH Aachen University, Aachen, Germany
| | - David L Bennett
- Nuffield Department of Clinical Neuroscience, Oxford University, Oxford, UK
| | - John N Wood
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London, UK
| | - Vincent Timmerman
- Peripheral Neuropathy Research Group, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium.,Laboratory of Neuromuscular Pathology, Institute Born Bunge, Antwerp, Belgium
| | - Thorsten Hornemann
- Department of Clinical Chemistry, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Michaela Auer-Grumbach
- Department of Orthopedics and Trauma Surgery, Medical University of Vienna, Vienna, Austria
| | - Yesim Parman
- Neuromuscular Unit, Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | | | - Miriam Elbracht
- Institute of Human Genetics, Medical Faculty, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Katja Eggermann
- Institute of Human Genetics, Medical Faculty, Uniklinik RWTH Aachen University, Aachen, Germany
| | - C Geoffrey Woods
- Cambridge Institute for Medical Research, Keith Peters Building, Cambridge Biomedical Campus, Cambridge, UK
| | - James J Cox
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London, UK
| | - Mary M Reilly
- Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
| | - Ingo Kurth
- Institute of Human Genetics, Medical Faculty, Uniklinik RWTH Aachen University, Aachen, Germany.
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22
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Xue Y, Kremer M, Muniz Moreno MDM, Chidiac C, Lorentz R, Birling MC, Barrot M, Herault Y, Gaveriaux-Ruff C. The Human SCN9AR185H Point Mutation Induces Pain Hypersensitivity and Spontaneous Pain in Mice. Front Mol Neurosci 2022; 15:913990. [PMID: 35769334 PMCID: PMC9234669 DOI: 10.3389/fnmol.2022.913990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 05/04/2022] [Indexed: 11/13/2022] Open
Abstract
The voltage-gated sodium channel Nav1.7 is encoded by SCN9A gene and plays a critical role in pain sensitivity. Several SCN9A gain-of-function (GOF) mutations have been found in patients with small fiber neuropathy (SFN) having chronic pain, including the R185H mutation. However, for most of these variants, their involvement in pain phenotype still needs to be experimentally elucidated. In order to delineate the impact of R185H mutation on pain sensitivity, we have established the Scn9aR185H mutant mouse model using the CRISPR/Cas9 technology. The Scn9aR185H mutant mice show no cellular alteration in the dorsal root ganglia (DRG) containing cell bodies of sensory neurons and no alteration of growth or global health state. Heterozygous and homozygous animals of both sexes were investigated for pain sensitivity. The mutant mice were more sensitive than the wild-type mice in the tail flick and hot plate tests, acetone, and von Frey tests for sensitivity to heat, cold, and touch, respectively, although with sexual dimorphic effects. The newly developed bioinformatic pipeline, Gdaphen is based on general linear model (GLM) and random forest (RF) classifiers as well as a multifactor analysis of mixed data and shows the qualitative and quantitative variables contributing the most to the pain phenotype. Using Gdaphen, tail flick, Hargreaves, hot plate, acetone, cold plate, and von Frey tests, sex and genotype were found to be contributing most to the pain phenotype. Importantly, the mutant animals displayed spontaneous pain as assessed in the conditioned place preference (CPP) assay. Altogether, our results indicate that Scn9aR185H mice show a pain phenotype, suggesting that the SCN9AR185H mutation identified in patients with SFN having chronic pain contributes to their symptoms. Therefore, we provide genetic evidence for the fact that this mutation in Nav1.7 channel plays an important role in nociception and in the pain experienced by patients with SFN who have this mutation. These findings should aid in exploring further pain treatments based on the Nav1.7 channel.
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Affiliation(s)
- Yaping Xue
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, Illkirch, France
| | - Mélanie Kremer
- Centre National de la Recherche Scientifique (CNRS), Institut des Neurosciences Cellulaires et Intégratives (INCI), Université de Strasbourg, Strasbourg, France
| | - Maria del Mar Muniz Moreno
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, Illkirch, France
| | - Celeste Chidiac
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, Illkirch, France
| | - Romain Lorentz
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), CELPHEDIA-PHENOMIN-Institut Clinique de la Souris, (PHENOMIN-ICS), Université de Strasbourg, Illkirch, France
| | - Marie-Christine Birling
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), CELPHEDIA-PHENOMIN-Institut Clinique de la Souris, (PHENOMIN-ICS), Université de Strasbourg, Illkirch, France
| | - Michel Barrot
- Centre National de la Recherche Scientifique (CNRS), Institut des Neurosciences Cellulaires et Intégratives (INCI), Université de Strasbourg, Strasbourg, France
| | - Yann Herault
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, Illkirch, France
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), CELPHEDIA-PHENOMIN-Institut Clinique de la Souris, (PHENOMIN-ICS), Université de Strasbourg, Illkirch, France
- *Correspondence: Yann Herault,
| | - Claire Gaveriaux-Ruff
- Centre National de la Recherche Scientifique (CNRS), Institut de la Santé et de la Recherche Médicale (INSERM), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, Illkirch, France
- Centre National de la Recherche Scientifique (CNRS) UMR 7242, Université de Strasbourg, Illkirch, France
- Claire Gaveriaux-Ruff,
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Novel Therapies for the Treatment of Neuropathic Pain: Potential and Pitfalls. J Clin Med 2022; 11:jcm11113002. [PMID: 35683390 PMCID: PMC9181614 DOI: 10.3390/jcm11113002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 05/20/2022] [Accepted: 05/24/2022] [Indexed: 12/15/2022] Open
Abstract
Neuropathic pain affects more than one million people across the globe. The quality of life of people suffering from neuropathic pain has been considerably declining due to the unavailability of appropriate therapeutics. Currently, available treatment options can only treat patients symptomatically, but they are associated with severe adverse side effects and the development of tolerance over prolonged use. In the past decade, researchers were able to gain a better understanding of the mechanisms involved in neuropathic pain; thus, continuous efforts are evident, aiming to develop novel interventions with better efficacy instead of symptomatic treatment. The current review discusses the latest interventional strategies used in the treatment and management of neuropathic pain. This review also provides insights into the present scenario of pain research, particularly various interventional techniques such as spinal cord stimulation, steroid injection, neural blockade, transcranial/epidural stimulation, deep brain stimulation, percutaneous electrical nerve stimulation, neuroablative procedures, opto/chemogenetics, gene therapy, etc. In a nutshell, most of the above techniques are at preclinical stage and facing difficulty in translation to clinical studies due to the non-availability of appropriate methodologies. Therefore, continuing research on these interventional strategies may help in the development of promising novel therapies that can improve the quality of life of patients suffering from neuropathic pain.
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24
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Kim DS, Kim SW, Gil HW. Emotional and cognitive changes in chronic kidney disease. Korean J Intern Med 2022; 37:489-501. [PMID: 35249316 PMCID: PMC9082446 DOI: 10.3904/kjim.2021.492] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 01/02/2022] [Indexed: 11/30/2022] Open
Abstract
Chronic kidney disease (CKD) leads to cognitive impairment and emotional changes. However, the precise mechanism underlying the crosstalk between the kidneys and the nervous system is not fully understood. Inflammation and cerebrovascular disease can influence the development of depression in CKD. CKD is one of the strongest risk factors for cognitive impairment. Moreover, cognitive impairment occurs in CKD as patients experience the dysregulation of several brain functional domains due to damage caused to multiple cortical regions and to subcortical modulatory neurons. The differences in structural brain changes between CKD and non-CKD dementia may be attributable to the different mechanisms that occur in CKD. The kidney and brain have similar anatomical vascular systems, which may be susceptible to traditional risk factors. Vascular factors are assumed to be involved in the development of cognitive impairment in patients with CKD. Vascular injury induces white matter lesions, silent infarction, and microbleeds. Uremic toxins may also be directly related to cognitive impairment in CKD. Many uremic toxins, such as indoxyl sulfate, are likely to have an impact on the central nervous system. Further studies are required to identify therapeutic targets to prevent changes in the brain in patients with CKD.
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Affiliation(s)
- Duk-Soo Kim
- Department of Anatomy, Soonchunhyang University College of Medicine, Cheonan,
Korea
| | - Seong-Wook Kim
- Graduate School of New Drug Discovery & Development, Chungnam National University, Daejeon,
Korea
| | - Hyo-Wook Gil
- Department of Internal Medicine, Soonchunhyang University Cheonan Hospital, Cheonan,
Korea
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25
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Chen Y, Xu E, Sang M, Wang Z, Zhang Y, Ye J, Zhou Q, Zhao C, Hu C, Lu W, Cao P. Makatoxin-3, a thermostable Nav1.7 agonist from Buthus martensii Karsch (BmK) scorpion elicits non-narcotic analgesia in inflammatory pain models. JOURNAL OF ETHNOPHARMACOLOGY 2022; 288:114998. [PMID: 35063590 DOI: 10.1016/j.jep.2022.114998] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/31/2021] [Accepted: 01/11/2022] [Indexed: 06/14/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Chronic pain management represents a serious healthcare problem worldwide. The use of opioid analgesics for pain has always been hampered by their side effects; in particular, the addictive liability associated with chronic use. Finding a morphine replacement has been a long-standing goal in the field of analgesia. In traditional Chinese medicine, processed Buthus martensii Karsch (BmK) scorpion has been used as a painkiller to treat chronic inflammatory arthritis and spondylitis, so called "Scorpio-analgesia". However, the molecular basis and the underline mechanism for the Scorpio-analgesia are still unclear. AIM OF THE STUDY The study aims to investigate the molecular basis of "Scorpio analgesia" and identify novel analgesics from BmK scorpion. MATERIALS AND METHODS In this study, the analgesic abilities were determined using formalin-, acetic acid- and complete Freund's adjuvant-induced pain models. The effect of BmK venom and processed BmK venom on Nav1.7 were detected by whole-cell voltage-clamp recordings on HEK293-hNav1.7 stable cell line. Action potentials in Dorsal root ganglion (DRG) neurons induced by Makatoxin-3-R58A were recorded in current-clamp mode. The content of Makatoxin-3 was detected using competitive enzyme-linked immunosorbent assay based on the Makatoxin-3 antibody. High performance liquid chromatography, western blot and circular dichroism spectroscopy were used to analysis the stability of Makatoxin-3. RESULTS Here we demonstrate that Makatoxin-3, an α-like toxin in BmK scorpion venom targeting Nav1.7 is the critical component in Scorpio-analgesia. The analgesic effect of Makatoxin-3 could not be reversed by naloxone and is more potent than Nav1.7-selective inhibitors and non-steroidal anti-inflammatory drugs in inflammatory models. Moreover, a R58A mutant of Makatoxin-3 is capable of eliciting analgesia effect without inducing pain response. CONCLUSIONS This study advances ion channel biology and proposes Nav1.7 agonists, rather than the presumed Nav1.7-only blockers, for non-narcotic relief of chronic pain.
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Affiliation(s)
- Yonggen Chen
- Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210028, China; School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210023, China
| | - Erjin Xu
- Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210028, China; School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210023, China
| | - Ming Sang
- Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210028, China
| | - Zhiheng Wang
- Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210028, China
| | - Yuxin Zhang
- Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210028, China; School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210023, China
| | - Juan Ye
- Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210028, China
| | - Qian Zhou
- Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210028, China
| | - Chenglei Zhao
- Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210028, China
| | - Chunping Hu
- Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210028, China
| | - Wuguang Lu
- Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210028, China; School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210023, China.
| | - Peng Cao
- Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210028, China; School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210023, China.
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26
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Alles SRA, Smith PA. Peripheral Voltage-Gated Cation Channels in Neuropathic Pain and Their Potential as Therapeutic Targets. FRONTIERS IN PAIN RESEARCH 2022; 2:750583. [PMID: 35295464 PMCID: PMC8915663 DOI: 10.3389/fpain.2021.750583] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 11/10/2021] [Indexed: 11/25/2022] Open
Abstract
The persistence of increased excitability and spontaneous activity in injured peripheral neurons is imperative for the development and persistence of many forms of neuropathic pain. This aberrant activity involves increased activity and/or expression of voltage-gated Na+ and Ca2+ channels and hyperpolarization activated cyclic nucleotide gated (HCN) channels as well as decreased function of K+ channels. Because they display limited central side effects, peripherally restricted Na+ and Ca2+ channel blockers and K+ channel activators offer potential therapeutic approaches to pain management. This review outlines the current status and future therapeutic promise of peripherally acting channel modulators. Selective blockers of Nav1.3, Nav1.7, Nav1.8, Cav3.2, and HCN2 and activators of Kv7.2 abrogate signs of neuropathic pain in animal models. Unfortunately, their performance in the clinic has been disappointing; some substances fail to meet therapeutic end points whereas others produce dose-limiting side effects. Despite this, peripheral voltage-gated cation channels retain their promise as therapeutic targets. The way forward may include (i) further structural refinement of K+ channel activators such as retigabine and ASP0819 to improve selectivity and limit toxicity; use or modification of Na+ channel blockers such as vixotrigine, PF-05089771, A803467, PF-01247324, VX-150 or arachnid toxins such as Tap1a; the use of Ca2+ channel blockers such as TTA-P2, TTA-A2, Z 944, ACT709478, and CNCB-2; (ii) improving methods for assessing “pain” as opposed to nociception in rodent models; (iii) recognizing sex differences in pain etiology; (iv) tailoring of therapeutic approaches to meet the symptoms and etiology of pain in individual patients via quantitative sensory testing and other personalized medicine approaches; (v) targeting genetic and biochemical mechanisms controlling channel expression using anti-NGF antibodies such as tanezumab or re-purposed drugs such as vorinostat, a histone methyltransferase inhibitor used in the management of T-cell lymphoma, or cercosporamide a MNK 1/2 inhibitor used in treatment of rheumatoid arthritis; (vi) combination therapy using drugs that are selective for different channel types or regulatory processes; (vii) directing preclinical validation work toward the use of human or human-derived tissue samples; and (viii) application of molecular biological approaches such as clustered regularly interspaced short palindromic repeats (CRISPR) technology.
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Affiliation(s)
- Sascha R A Alles
- Department of Anesthesiology and Critical Care Medicine, University of New Mexico School of Medicine, Albuquerque, NM, United States
| | - Peter A Smith
- Department of Pharmacology, Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
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27
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Labau JIR, Alsaloum M, Estacion M, Tanaka B, Dib-Hajj FB, Lauria G, Smeets HJM, Faber CG, Dib-Hajj S, Waxman SG. Lacosamide Inhibition of Na V1.7 Channels Depends on its Interaction With the Voltage Sensor Domain and the Channel Pore. Front Pharmacol 2022; 12:791740. [PMID: 34992539 PMCID: PMC8724789 DOI: 10.3389/fphar.2021.791740] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 12/02/2021] [Indexed: 12/14/2022] Open
Abstract
Lacosamide, developed as an anti-epileptic drug, has been used for the treatment of pain. Unlike typical anticonvulsants and local anesthetics which enhance fast-inactivation and bind within the pore of sodium channels, lacosamide enhances slow-inactivation of these channels, suggesting different binding mechanisms and mode of action. It has been reported that lacosamide's effect on NaV1.5 is sensitive to a mutation in the local anesthetic binding site, and that it binds with slow kinetics to the fast-inactivated state of NaV1.7. We recently showed that the NaV1.7-W1538R mutation in the voltage-sensing domain 4 completely abolishes NaV1.7 inhibition by clinically-achievable concentration of lacosamide. Our molecular docking analysis suggests a role for W1538 and pore residues as high affinity binding sites for lacosamide. Aryl sulfonamide sodium channel blockers are also sensitive to substitutions of the W1538 residue but not of pore residues. To elucidate the mechanism by which lacosamide exerts its effects, we used voltage-clamp recordings and show that lacosamide requires an intact local anesthetic binding site to inhibit NaV1.7 channels. Additionally, the W1538R mutation does not abrogate local anesthetic lidocaine-induced blockade. We also show that the naturally occurring arginine in NaV1.3 (NaV1.3-R1560), which corresponds to NaV1.7-W1538R, is not sufficient to explain the resistance of NaV1.3 to clinically-relevant concentrations of lacosamide. However, the NaV1.7-W1538R mutation conferred sensitivity to the NaV1.3-selective aryl-sulfonamide blocker ICA-121431. Together, the W1538 residue and an intact local anesthetic site are required for lacosamide's block of NaV1.7 at a clinically-achievable concentration. Moreover, the contribution of W1538 to lacosamide inhibitory effects appears to be isoform-specific.
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Affiliation(s)
- Julie I R Labau
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT, United States.,Rehabilitation Research Center, Veteran Affairs Connecticut Healthcare System, West Haven, CT, United States.,Department of Toxicogenomics, Clinical Genomics, Maastricht University Medical Centre+, Maastricht, Netherlands.,School of Mental Health and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Matthew Alsaloum
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT, United States.,Rehabilitation Research Center, Veteran Affairs Connecticut Healthcare System, West Haven, CT, United States.,Yale Medical Scientist Training Program, Yale School of Medicine, New Haven, CT, United States.,Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT, United States
| | - Mark Estacion
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT, United States.,Rehabilitation Research Center, Veteran Affairs Connecticut Healthcare System, West Haven, CT, United States
| | - Brian Tanaka
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT, United States.,Rehabilitation Research Center, Veteran Affairs Connecticut Healthcare System, West Haven, CT, United States
| | - Fadia B Dib-Hajj
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT, United States.,Rehabilitation Research Center, Veteran Affairs Connecticut Healthcare System, West Haven, CT, United States
| | - Giuseppe Lauria
- Neuroalgology Unit, IRCCS Foundation, "Carlo Besta" Neurological Institute, Milan, Italy.,Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Hubert J M Smeets
- Department of Toxicogenomics, Clinical Genomics, Maastricht University Medical Centre+, Maastricht, Netherlands.,School of Mental Health and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Catharina G Faber
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, Netherlands
| | - Sulayman Dib-Hajj
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT, United States.,Rehabilitation Research Center, Veteran Affairs Connecticut Healthcare System, West Haven, CT, United States
| | - Stephen G Waxman
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT, United States.,Rehabilitation Research Center, Veteran Affairs Connecticut Healthcare System, West Haven, CT, United States
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28
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Iseppon F, Linley JE, Wood JN. Calcium imaging for analgesic drug discovery. NEUROBIOLOGY OF PAIN 2022; 11:100083. [PMID: 35079661 PMCID: PMC8777277 DOI: 10.1016/j.ynpai.2021.100083] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 12/17/2021] [Accepted: 12/27/2021] [Indexed: 11/24/2022]
Abstract
Calcium imaging is an efficient way to dissect the activity of neurons in vivo. GCaMP indicators can be expressed in specific cell populations for in vivo imaging. Pain research have benefitted greatly from these features in the recent decade. Preclinical research is shifting towards the analysis of pain models and mechanisms. In vivo calcium imaging is the ideal tool for an efficient drug discovery paradigm.
Somatosensation and pain are complex phenomena involving a rangeofspecialised cell types forming different circuits within the peripheral and central nervous systems. In recent decades, advances in the investigation of these networks, as well as their function in sensation, resulted from the constant evolution of electrophysiology and imaging techniques to allow the observation of cellular activity at the population level both in vitro and in vivo. Genetically encoded indicators of neuronal activity, combined with recent advances in DNA engineering and modern microscopy, offer powerful tools to dissect and visualise the activity of specific neuronal subpopulations with high spatial and temporal resolution. In recent years various groups developed in vivo imaging techniques to image calcium transients in the dorsal root ganglia, the spinal cord and the brain of anesthetised and awake, behaving animals to address fundamental questions in both the physiology and pathophysiology of somatosensation and pain. This approach, besides giving unprecedented details on the circuitry of innocuous and painful sensation, can be a very powerful tool for pharmacological research, from the characterisation of new potential drugs to the discovery of new, druggable targets within specific neuronal subpopulations. Here we summarise recent developments in calcium imaging for pain research, discuss technical challenges and advances, and examine the potential positive impact of this technique in early preclinical phases of the analgesic drug discovery process.
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29
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Cai S, Moutal A, Yu J, Chew LA, Isensee J, Chawla R, Gomez K, Luo S, Zhou Y, Chefdeville A, Madura C, Perez-Miller S, Bellampalli SS, Dorame A, Scott DD, François-Moutal L, Shan Z, Woodward T, Gokhale V, Hohmann AG, Vanderah TW, Patek M, Khanna M, Hucho T, Khanna R. Selective targeting of NaV1.7 via inhibition of the CRMP2-Ubc9 interaction reduces pain in rodents. Sci Transl Med 2021; 13:eabh1314. [PMID: 34757807 DOI: 10.1126/scitranslmed.abh1314] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The voltage-gated sodium NaV1.7 channel, critical for sensing pain, has been actively targeted by drug developers; however, there are currently no effective and safe therapies targeting NaV1.7. Here, we tested whether a different approach, indirect NaV1.7 regulation, could have antinociceptive effects in preclinical models. We found that preventing addition of small ubiquitin-like modifier (SUMO) on the NaV1.7-interacting cytosolic collapsin response mediator protein 2 (CRMP2) blocked NaV1.7 functions and had antinociceptive effects in rodents. In silico targeting of the SUMOylation site in CRMP2 (Lys374) identified >200 hits, of which compound 194 exhibited selective in vitro and ex vivo NaV1.7 engagement. Orally administered 194 was not only antinociceptive in preclinical models of acute and chronic pain but also demonstrated synergy alongside other analgesics—without eliciting addiction, rewarding properties, or neurotoxicity. Analgesia conferred by 194 was opioid receptor dependent. Our results demonstrate that 194 is a first-in-class protein-protein inhibitor that capitalizes on CRMP2-NaV1.7 regulation to deliver safe analgesia in rodents.
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Affiliation(s)
- Song Cai
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
| | - Aubin Moutal
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
| | - Jie Yu
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
| | - Lindsey A Chew
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
| | - Jörg Isensee
- Department of Anesthesiology and Intensive Care Medicine, Translational Pain Research, University Hospital of Cologne, University Cologne, Joseph-Stelzmann-Str 9, Cologne D-50931, Germany
| | - Reena Chawla
- BIO5 Institute, 1657 East Helen Street, Tucson, AZ 85721, USA
| | - Kimberly Gomez
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
| | - Shizhen Luo
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
| | - Yuan Zhou
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
| | - Aude Chefdeville
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
| | - Cynthia Madura
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
| | - Samantha Perez-Miller
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
- Center for Innovation in Brain Sciences, University of Arizona, Tucson, AZ 85721, USA
| | - Shreya Sai Bellampalli
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
| | - Angie Dorame
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
| | - David D Scott
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
| | - Liberty François-Moutal
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
| | - Zhiming Shan
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
| | - Taylor Woodward
- Department of Psychological and Brain Sciences, Program in Neuroscience and Gill Center for Biomolecular Science, Indiana University, Bloomington, IN 47405-2204, USA
| | - Vijay Gokhale
- BIO5 Institute, 1657 East Helen Street, Tucson, AZ 85721, USA
- College of Pharmacy, University of Arizona, 1703 East Mabel Street, Tucson, AZ 85721, USA
| | - Andrea G Hohmann
- Department of Psychological and Brain Sciences, Program in Neuroscience and Gill Center for Biomolecular Science, Indiana University, Bloomington, IN 47405-2204, USA
| | - Todd W Vanderah
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
- Comprehensive Pain and Addiction Center, The University of Arizona, Tucson, AZ 85724, USA
| | - Marcel Patek
- Regulonix LLC, 1555 E. Entrada Segunda, Tucson, AZ 85718, USA
- Bright Rock Path LLC, Tucson, AZ 85724, USA
| | - May Khanna
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
- BIO5 Institute, 1657 East Helen Street, Tucson, AZ 85721, USA
- Center for Innovation in Brain Sciences, University of Arizona, Tucson, AZ 85721, USA
- Regulonix LLC, 1555 E. Entrada Segunda, Tucson, AZ 85718, USA
| | - Tim Hucho
- Department of Anesthesiology and Intensive Care Medicine, Translational Pain Research, University Hospital of Cologne, University Cologne, Joseph-Stelzmann-Str 9, Cologne D-50931, Germany
| | - Rajesh Khanna
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
- BIO5 Institute, 1657 East Helen Street, Tucson, AZ 85721, USA
- Center for Innovation in Brain Sciences, University of Arizona, Tucson, AZ 85721, USA
- Comprehensive Pain and Addiction Center, The University of Arizona, Tucson, AZ 85724, USA
- Regulonix LLC, 1555 E. Entrada Segunda, Tucson, AZ 85718, USA
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30
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The cellular and molecular basis of somatosensory neuron development. Neuron 2021; 109:3736-3757. [PMID: 34592169 DOI: 10.1016/j.neuron.2021.09.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/23/2021] [Accepted: 09/01/2021] [Indexed: 11/23/2022]
Abstract
Primary somatosensory neurons convey salient information about our external environment and internal state to the CNS, allowing us to detect, perceive, and react to a wide range of innocuous and noxious stimuli. Pseudo-unipolar in shape, and among the largest (longest) cells of most mammals, dorsal root ganglia (DRG) somatosensory neurons have peripheral axons that extend into skin, muscle, viscera, or bone and central axons that innervate the spinal cord and brainstem, where they synaptically engage the central somatosensory circuitry. Here, we review the diversity of mammalian DRG neuron subtypes and the intrinsic and extrinsic mechanisms that control their development. We describe classical and contemporary advances that frame our understanding of DRG neurogenesis, transcriptional specification of DRG neurons, and the establishment of morphological, physiological, and synaptic diversification across somatosensory neuron subtypes.
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Middleton SJ, Perez-Sanchez J, Dawes JM. The structure of sensory afferent compartments in health and disease. J Anat 2021; 241:1186-1210. [PMID: 34528255 PMCID: PMC9558153 DOI: 10.1111/joa.13544] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 08/12/2021] [Accepted: 08/30/2021] [Indexed: 12/20/2022] Open
Abstract
Primary sensory neurons are a heterogeneous population of cells able to respond to both innocuous and noxious stimuli. Like most neurons they are highly compartmentalised, allowing them to detect, convey and transfer sensory information. These compartments include specialised sensory endings in the skin, the nodes of Ranvier in myelinated axons, the cell soma and their central terminals in the spinal cord. In this review, we will highlight the importance of these compartments to primary afferent function, describe how these structures are compromised following nerve damage and how this relates to neuropathic pain.
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Affiliation(s)
- Steven J Middleton
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | | | - John M Dawes
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
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Hurtado-Lorenzo A, Honig G, Weaver SA, Larkin PB, Heller C. Chronic Abdominal Pain in IBD Research Initiative: Unraveling Biological Mechanisms and Patient Heterogeneity to Personalize Treatment and Improve Clinical Outcomes. CROHN'S & COLITIS 360 2021; 3:otab034. [PMID: 36776666 PMCID: PMC9802354 DOI: 10.1093/crocol/otab034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Andrés Hurtado-Lorenzo
- Research Department, Crohn’s & Colitis Foundation, New York, New York, USA,Address correspondence to: Andrés Hurtado-Lorenzo, PhD, Crohn’s & Colitis Foundation, 733 3rd Ave Suite 510, New York, NY 10017, USA ()
| | - Gerard Honig
- Research Department, Crohn’s & Colitis Foundation, New York, New York, USA
| | | | - Paul B Larkin
- Research Department, Crohn’s & Colitis Foundation, New York, New York, USA
| | - Caren Heller
- Research Department, Crohn’s & Colitis Foundation, New York, New York, USA
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Locus revealed: Painlessness via loss of Na V1.7 at central terminals of sensory neurons. Neuron 2021; 109:1413-1416. [PMID: 33957067 DOI: 10.1016/j.neuron.2021.04.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
How genetic loss of the sodium channel NaV1.7 results in painlessness is puzzling. MacDonald et al. (2021) demonstrate that instead of impairing peripheral excitability, NaV1.7 channels at central terminals of pain-sensing afferents play a pivotal role in the balance between pain and analgesia.
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Santana-Varela S, Bogdanov YD, Gossage SJ, Okorokov AL, Li S, de Clauser L, Alves-Simoes M, Sexton JE, Iseppon F, Luiz AP, Zhao J, Wood JN, Cox JJ. Tools for analysis and conditional deletion of subsets of sensory neurons. Wellcome Open Res 2021; 6:250. [PMID: 35233469 PMCID: PMC8817070 DOI: 10.12688/wellcomeopenres.17090.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/06/2021] [Indexed: 12/03/2022] Open
Abstract
Background: Somatosensation depends on primary sensory neurons of the trigeminal and dorsal root ganglia (DRG). Transcriptional profiling of mouse DRG sensory neurons has defined at least 18 distinct neuronal cell types. Using an advillin promoter, we have generated a transgenic mouse line that only expresses diphtheria toxin A (DTA) in sensory neurons in the presence of Cre recombinase. This has allowed us to ablate specific neuronal subsets within the DRG using a range of established and novel Cre lines that encompass all sets of sensory neurons. Methods: A floxed-tdTomato-stop-DTA bacterial artificial chromosome (BAC) transgenic reporter line (AdvDTA) under the control of the mouse advillin DRG promoter was generated. The line was first validated using a Na v1.8 Cre and then crossed to CGRP CreER (Calca), Th CreERT2, Tmem45b Cre, Tmem233 Cre, Ntng1 Cre and TrkB CreER (Ntrk2) lines. Pain behavioural assays included Hargreaves', hot plate, Randall-Selitto, cold plantar, partial sciatic nerve ligation and formalin tests. Results: Motor activity, as assessed by the rotarod test, was normal for all lines tested. Noxious mechanosensation was significantly reduced when either Na v1.8 positive neurons or Tmem45b positive neurons were ablated whilst acute heat pain was unaffected. In contrast, noxious mechanosensation was normal following ablation of CGRP-positive neurons but acute heat pain thresholds were significantly elevated and a reduction in nocifensive responses was observed in the second phase of the formalin test. Ablation of TrkB-positive neurons led to significant deficits in mechanical hypersensitivity in the partial sciatic nerve ligation neuropathic pain model. Conclusions: Ablation of specific DRG neuronal subsets using the AdvDTA line will be a useful resource for further functional characterization of somatosensory processing, neuro-immune interactions and chronic pain disorders.
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Affiliation(s)
| | - Yury D. Bogdanov
- Molecular Nociception Group, University College London, London, WC1E 6BT, UK
- Antibody and Vaccine Group, Centre for Cancer Immunology, MP127, University of Southampton Faculty of Medicine, Southampton, SO166YD, UK
| | - Samuel J. Gossage
- Molecular Nociception Group, University College London, London, WC1E 6BT, UK
| | - Andrei L. Okorokov
- Molecular Nociception Group, University College London, London, WC1E 6BT, UK
| | - Shengnan Li
- Molecular Nociception Group, University College London, London, WC1E 6BT, UK
| | - Larissa de Clauser
- Molecular Nociception Group, University College London, London, WC1E 6BT, UK
- Institute for Biomedicine, Affiliated Institute of the University of Lubeck, Bolzano, Italy
| | - Marta Alves-Simoes
- Molecular Nociception Group, University College London, London, WC1E 6BT, UK
| | - Jane E. Sexton
- Molecular Nociception Group, University College London, London, WC1E 6BT, UK
| | - Federico Iseppon
- Molecular Nociception Group, University College London, London, WC1E 6BT, UK
| | - Ana P. Luiz
- Molecular Nociception Group, University College London, London, WC1E 6BT, UK
| | - Jing Zhao
- Molecular Nociception Group, University College London, London, WC1E 6BT, UK
| | - John N. Wood
- Molecular Nociception Group, University College London, London, WC1E 6BT, UK
| | - James J. Cox
- Molecular Nociception Group, University College London, London, WC1E 6BT, UK
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