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Martina M, Banderali U, Yogi A, Arbabi Ghahroudi M, Liu H, Sulea T, Durocher Y, Hussack G, van Faassen H, Chakravarty B, Liu QY, Iqbal U, Ling B, Lessard E, Sheff J, Robotham A, Callaghan D, Moreno M, Comas T, Ly D, Stanimirovic D. A Novel Antigen Design Strategy to Isolate Single-Domain Antibodies that Target Human Nav1.7 and Reduce Pain in Animal Models. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024:e2405432. [PMID: 39206821 DOI: 10.1002/advs.202405432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 08/01/2024] [Indexed: 09/04/2024]
Abstract
Genetic studies have identified the voltage-gated sodium channel 1.7 (Nav1.7) as pain target. Due to the ineffectiveness of small molecules and monoclonal antibodies as therapeutics for pain, single-domain antibodies (VHHs) are developed against the human Nav1.7 (hNav1.7) using a novel antigen presentation strategy. A 70 amino-acid peptide from the hNav1.7 protein is identified as a target antigen. A recombinant version of this peptide is grafted into the complementarity determining region 3 (CDR3) loop of an inert VHH in order to maintain the native 3D conformation of the peptide. This antigen is used to isolate one VHH able to i) bind hNav1.7, ii) slow the deactivation of hNav1.7, iii) reduce the ability of eliciting action potentials in nociceptors, and iv) reverse hyperalgesia in in vivo rat and mouse models. This VHH exhibits the potential to be developed as a therapeutic capable of suppressing pain. This novel antigen presentation strategy can be applied to develop biologics against other difficult targets such as ion channels, transporters and GPCRs.
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Affiliation(s)
- Marzia Martina
- Human Health Therapeutics Research Center, National Research Council Canada, 1200 Montreal Road, Building M54, Ottawa, ON, K1A 0R6, Canada
| | - Umberto Banderali
- Human Health Therapeutics Research Center, National Research Council Canada, 1200 Montreal Road, Building M54, Ottawa, ON, K1A 0R6, Canada
| | - Alvaro Yogi
- Human Health Therapeutics Research Center, National Research Council Canada, 1200 Montreal Road, Building M54, Ottawa, ON, K1A 0R6, Canada
| | - Mehdi Arbabi Ghahroudi
- Human Health Therapeutics Research Centre, National Research Council Canada, 100 Sussex Drive, Ottawa, ON, K1N 5A2, Canada
| | - Hong Liu
- Human Health Therapeutics Research Center, National Research Council Canada, 1200 Montreal Road, Building M54, Ottawa, ON, K1A 0R6, Canada
| | - Traian Sulea
- Human Health Therapeutics Research Centre, National Research Council Canada, 6100 Royalmount Avenue Montréal, Quebec, H4P 2R2, Canada
| | - Yves Durocher
- Human Health Therapeutics Research Centre, National Research Council Canada, 6100 Royalmount Avenue Montréal, Quebec, H4P 2R2, Canada
| | - Greg Hussack
- Human Health Therapeutics Research Centre, National Research Council Canada, 100 Sussex Drive, Ottawa, ON, K1N 5A2, Canada
| | - Henk van Faassen
- Human Health Therapeutics Research Centre, National Research Council Canada, 100 Sussex Drive, Ottawa, ON, K1N 5A2, Canada
| | - Balu Chakravarty
- Human Health Therapeutics Research Center, National Research Council Canada, 1200 Montreal Road, Building M54, Ottawa, ON, K1A 0R6, Canada
| | - Qing Yan Liu
- Human Health Therapeutics Research Center, National Research Council Canada, 1200 Montreal Road, Building M54, Ottawa, ON, K1A 0R6, Canada
| | - Umar Iqbal
- Human Health Therapeutics Research Center, National Research Council Canada, 1200 Montreal Road, Building M54, Ottawa, ON, K1A 0R6, Canada
| | - Binbing Ling
- Human Health Therapeutics Research Center, National Research Council Canada, 1200 Montreal Road, Building M54, Ottawa, ON, K1A 0R6, Canada
| | - Etienne Lessard
- Human Health Therapeutics Research Centre, National Research Council Canada, 6100 Royalmount Avenue Montréal, Quebec, H4P 2R2, Canada
| | - Joey Sheff
- Human Health Therapeutics Research Centre, National Research Council Canada, 100 Sussex Drive, Ottawa, ON, K1N 5A2, Canada
| | - Anna Robotham
- Human Health Therapeutics Research Centre, National Research Council Canada, 100 Sussex Drive, Ottawa, ON, K1N 5A2, Canada
| | - Debbie Callaghan
- Human Health Therapeutics Research Centre, National Research Council Canada, 100 Sussex Drive, Ottawa, ON, K1N 5A2, Canada
| | - Maria Moreno
- Human Health Therapeutics Research Center, National Research Council Canada, 1200 Montreal Road, Building M54, Ottawa, ON, K1A 0R6, Canada
| | - Tanya Comas
- Human Health Therapeutics Research Center, National Research Council Canada, 1200 Montreal Road, Building M54, Ottawa, ON, K1A 0R6, Canada
| | - Dao Ly
- Human Health Therapeutics Research Center, National Research Council Canada, 1200 Montreal Road, Building M54, Ottawa, ON, K1A 0R6, Canada
| | - Danica Stanimirovic
- Human Health Therapeutics Research Center, National Research Council Canada, 1200 Montreal Road, Building M54, Ottawa, ON, K1A 0R6, Canada
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Noguchi A, Tezuka T, Okuda H, Kobayashi H, Harada KH, Yoshida T, Akioka S, Wada K, Takeya A, Kabata-Murasawa R, Kondo D, Ishikawa K, Asano T, Fujiwara M, Hishikawa N, Mizukami T, Hitomi T, Youssefian S, Nagai Y, Tanaka M, Eto K, Shiraishi H, Amaya F, Koizumi A, Takahashi T. Genetic Analysis of SCN11A, SCN10A, and SCN9A in Familial Episodic Pain Syndrome (FEPS) in Japan and Proposal of Clinical Diagnostic Criteria. Int J Mol Sci 2024; 25:6832. [PMID: 38999942 PMCID: PMC11241565 DOI: 10.3390/ijms25136832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 06/09/2024] [Accepted: 06/16/2024] [Indexed: 07/14/2024] Open
Abstract
Familial episodic pain syndrome (FEPS) is an early childhood onset disorder of severe episodic limb pain caused mainly by pathogenic variants of SCN11A, SCN10A, and SCN9A, which encode three voltage-gated sodium channels (VGSCs) expressed as key determinants of nociceptor excitability in primary sensory neurons. There may still be many undiagnosed patients with FEPS. A better understanding of the associated pathogenesis, epidemiology, and clinical characteristics is needed to provide appropriate diagnosis and care. For this study, nationwide recruitment of Japanese patients was conducted using provisional clinical diagnostic criteria, followed by genetic testing for SCN11A, SCN10A, and SCN9A. In the cohort of 212 recruited patients, genetic testing revealed that 64 patients (30.2%) harbored pathogenic or likely pathogenic variants of these genes, consisting of 42 (19.8%), 14 (6.60%), and 8 (3.77%) patients with variants of SCN11A, SCN10A, and SCN9A, respectively. Meanwhile, the proportions of patients meeting the tentative clinical criteria were 89.1%, 52.0%, and 54.5% among patients with pathogenic or likely pathogenic variants of each of the three genes, suggesting the validity of these clinical criteria, especially for patients with SCN11A variants. These clinical diagnostic criteria of FEPS will accelerate the recruitment of patients with underlying pathogenic variants who are unexpectedly prevalent in Japan.
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Affiliation(s)
- Atsuko Noguchi
- Department of Pediatrics, Akita University Graduate School of Medicine, 1-1-1 Hondo, Akita 010-8543, Japan;
| | - Tohru Tezuka
- Department of Pain Pharmacogenetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; (T.T.); (H.O.); (A.T.); (S.Y.); (A.K.)
- Laboratory of Integrative Molecular Medicine, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Hiroko Okuda
- Department of Pain Pharmacogenetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; (T.T.); (H.O.); (A.T.); (S.Y.); (A.K.)
- Department of Preventive Medicine, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki 216-8511, Japan;
| | - Hatasu Kobayashi
- Department of Environmental and Molecular Medicine, Mie University Graduate School of Medicine, Edobashi 2-174, Tsu 514-8507, Japan;
| | - Kouji H. Harada
- Department of Health and Environmental Sciences, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan;
| | - Takeshi Yoshida
- Department of Pediatrics, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan;
| | - Shinji Akioka
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan;
| | - Keiko Wada
- Department of Epidemiology and Preventive Medicine, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu 501-1194, Japan;
| | - Aya Takeya
- Department of Pain Pharmacogenetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; (T.T.); (H.O.); (A.T.); (S.Y.); (A.K.)
- Department of Gynecology, Kyoto Okamoto Memorial Hospital, 100 Sayamanishi-No-Kuchi, Kumiyama-cho, Kuse-gun, Kyoto 613-0034, Japan
| | - Risako Kabata-Murasawa
- Department of Psychiatry, Iwate Prefectural Nanko Hospital, 17 Ohira, Kitsunezenji, Ichinoseki-shi 027-0031, Japan;
| | - Daiki Kondo
- Devision of Pediatrics, Akita Kousei Medical Center, 1-1-1 Iijima Nishibukuro, Akita 011-0948, Japan;
| | - Ken Ishikawa
- Department of Pediatrics, Iwate Medical University, 1-1 Iidai-dori 2-Chome, Yahaba-cho, Shiwa-gun 028-3695, Japan
| | - Takeshi Asano
- Department of Pediatrics, Nippon Medical School Chiba Hokusoh Hospital, 1715 Kamagari, Inzai 270-1694, Japan;
| | - Michimasa Fujiwara
- Department of Pediatrics, NHO Fukuyama Medical Center, 14-17, 4-Chome, Okinogami-cho, Fukuyama City 720-8520, Japan;
| | - Nozomi Hishikawa
- Department of Neurology, Kurashiki Heisei Hospital, 4-3-38 Oimatsu-cho, Kurashiki City 710-0826, Japan;
| | - Tomoyuki Mizukami
- Department of Pediatrics, National Hospital Organization Kumamoto Medical Center, 1-5 Ninomaru, Chuo-ku, Kumamoto 860-0008, Japan
| | - Toshiaki Hitomi
- Department of Preventive Medicine, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki 216-8511, Japan;
| | - Shohab Youssefian
- Department of Pain Pharmacogenetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; (T.T.); (H.O.); (A.T.); (S.Y.); (A.K.)
- Laboratory of Molecular Biosciences, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yoshihiro Nagai
- Department of Pain Management and Palliative Care Medicine, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan; (Y.N.); (F.A.)
| | - Manabu Tanaka
- Division of General Pediatrics, Saitama Prefectural Children’s Medical Center, 1-2 Shin-Toshin, Chuo-ku, Saitama 330-8777, Japan;
| | - Kaoru Eto
- Department of Pediatrics, Tokyo Women’s Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666, Japan;
| | - Hideaki Shiraishi
- Department of Pediatrics, Hokkaido University Hospital, North 15, West 7, Kita-ku, Sapporo 060-8638, Japan;
| | - Fumimasa Amaya
- Department of Pain Management and Palliative Care Medicine, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan; (Y.N.); (F.A.)
| | - Akio Koizumi
- Department of Pain Pharmacogenetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; (T.T.); (H.O.); (A.T.); (S.Y.); (A.K.)
- Institute of Public Health and Welfare Research, 18-13 Uzumasa Tanamoricho, Ukyo-ku, Kyoto 616-8141, Japan
| | - Tsutomu Takahashi
- Department of Pediatrics, Akita University Graduate School of Medicine, 1-1-1 Hondo, Akita 010-8543, Japan;
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Caldito EG, Kaul S, Caldito NG, Piette W, Mehta S. Erythromelalgia. Part I: Pathogenesis, clinical features, evaluation, and complications. J Am Acad Dermatol 2024; 90:453-462. [PMID: 37364617 DOI: 10.1016/j.jaad.2023.02.071] [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: 10/12/2022] [Revised: 01/27/2023] [Accepted: 02/12/2023] [Indexed: 06/28/2023]
Abstract
Erythromelalgia is a rare pain disorder that is underrecognized and difficult-to-treat. It is characterized by episodes of extremity erythema and pain that can be disabling; it may be genetic, related to an underlying systemic disease, or idiopathic. Considering the prominent cutaneous features characteristic of the condition, dermatologists can play an important role in early recognition and limitation of morbidity. The first article in this 2-part continuing medical education series reviews the epidemiology, pathogenesis, clinical manifestations, evaluation, and complications.
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Affiliation(s)
| | - Subuhi Kaul
- Division of Dermatology, John H Stroger Hospital of Cook County, Chicago, Illinois
| | | | - Warren Piette
- Division of Dermatology, John H Stroger Hospital of Cook County, Chicago, Illinois; Department of Dermatology, Rush University Medical Center, Chicago, Illinois
| | - Shilpa Mehta
- Division of Dermatology, John H Stroger Hospital of Cook County, Chicago, Illinois.
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4
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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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5
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Lyssenko V, Vaag A. Genetics of diabetes-associated microvascular complications. Diabetologia 2023; 66:1601-1613. [PMID: 37452207 PMCID: PMC10390394 DOI: 10.1007/s00125-023-05964-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 04/27/2023] [Indexed: 07/18/2023]
Abstract
Diabetes is associated with excess morbidity and mortality due to both micro- and macrovascular complications, as well as a range of non-classical comorbidities. Diabetes-associated microvascular complications are those considered most closely related to hyperglycaemia in a causal manner. However, some individuals with hyperglycaemia (even those with severe hyperglycaemia) do not develop microvascular diseases, which, together with evidence of co-occurrence of microvascular diseases in families, suggests a role for genetics. While genome-wide association studies (GWASs) produced firm evidence of multiple genetic variants underlying differential susceptibility to type 1 and type 2 diabetes, genetic determinants of microvascular complications are mostly suggestive. Identified susceptibility variants of diabetic kidney disease (DKD) in type 2 diabetes mirror variants underlying chronic kidney disease (CKD) in individuals without diabetes. As for retinopathy and neuropathy, reported risk variants currently lack large-scale replication. The reported associations between type 2 diabetes risk variants and microvascular complications may be explained by hyperglycaemia. More extensive phenotyping, along with adjustments for unmeasured confounding, including both early (fetal) and late-life (hyperglycaemia, hypertension, etc.) environmental factors, are urgently needed to understand the genetics of microvascular complications. Finally, genetic variants associated with reduced glycolysis, mitochondrial dysfunction and DNA damage and sustained cell regeneration may protect against microvascular complications, illustrating the utility of studies in individuals who have escaped these complications.
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Affiliation(s)
- Valeriya Lyssenko
- Department of Clinical Science, Mohn Research Center for Diabetes Precision Medicine, University of Bergen, Bergen, Norway.
- Department of Clinical Sciences, Lund University Diabetes Center, Lund University, Lund, Sweden.
| | - Allan Vaag
- Department of Clinical Sciences, Lund University Diabetes Center, Lund University, Lund, Sweden
- Steno Diabetes Center Copenhagen, Herlev, Denmark
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6
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Zuo L, Su A, Shi Y, Li N, Chen S, Yang X. Case report: Spinal cord stimulation in the treatment of pediatric erythromelalgia. Front Neurol 2023; 14:1143241. [PMID: 37273700 PMCID: PMC10233004 DOI: 10.3389/fneur.2023.1143241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 04/27/2023] [Indexed: 06/06/2023] Open
Abstract
Introduction In children, erythromelalgia is a rare chronic pain syndrome characterized by erythema, severe burning pain, and itching of affected feet. Unfortunately, there is no definitive therapy available currently. Case report Here, we report a case of primary erythromelalgia and the treatment response in a 10-year-old boy, whose genetic findings for mutations in the SCN9A gene were positive and skin biopsy results were diagnosed as small fiber neuropathy, while he has suffered from excruciating burning pain, itching, erythema, and recurrent infections over the past 3 years. He did not respond well to conventional treatment, and the only way to receive minimal relief was to immerse his feet in ice water. After a successful trial of spinal cord stimulation (SCS), the implantable pulse generator (IPG) was successfully implanted without complications, and it proved partial response to therapy. Conclusion There is no specific, efficient treatment for pediatric erythromelalgia currently, but this case demonstrates neuromodulation serves as part of the multimodal regimen to treat pediatric erythromelalgia.
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7
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Alsaloum M, Labau JIR, Liu S, Effraim PR, Waxman SG. Stem cell-derived sensory neurons modelling inherited erythromelalgia: normalization of excitability. Brain 2023; 146:359-371. [PMID: 35088838 DOI: 10.1093/brain/awac031] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 12/30/2021] [Accepted: 01/06/2022] [Indexed: 01/11/2023] Open
Abstract
Effective treatment of pain remains an unmet healthcare need that requires new and effective therapeutic approaches. NaV1.7 has been genetically and functionally validated as a mediator of pain. Preclinical studies of NaV1.7-selective blockers have shown limited success and translation to clinical studies has been limited. The degree of NaV1.7 channel blockade necessary to attenuate neuronal excitability and ameliorate pain is an unanswered question important for drug discovery. Here, we utilize dynamic clamp electrophysiology and induced pluripotent stem cell-derived sensory neurons (iPSC-SNs) to answer this question for inherited erythromelalgia, a pain disorder caused by gain-of-function mutations in Nav1.7. We show that dynamic clamp can produce hyperexcitability in iPSC-SNs associated with two different inherited erythromelalgia mutations, NaV1.7-S241T and NaV1.7-I848T. We further show that blockade of approximately 50% of NaV1.7 currents can reverse neuronal hyperexcitability to baseline levels.
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Affiliation(s)
- Matthew Alsaloum
- Department of Neurology, Yale School of Medicine, New Haven, CT 06510, USA.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT 06516, USA.,Center for Rehabilitation Research, VA Connecticut Healthcare System, West Haven, CT 06516, USA.,Yale Medical Scientist Training Program, Yale School of Medicine, New Haven, CT 06510, USA.,Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA
| | - Julie I R Labau
- Department of Neurology, Yale School of Medicine, New Haven, CT 06510, USA.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT 06516, USA.,Center for Rehabilitation Research, VA Connecticut Healthcare System, West Haven, CT 06516, USA.,Department of Clinical Epidemiology and Medical Technology Assessment (KEMTA), Maastricht University Medical Centre, Maastricht, The Netherlands.,Department of Clinical Genetics, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Shujun Liu
- Department of Neurology, Yale School of Medicine, New Haven, CT 06510, USA.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT 06516, USA.,Center for Rehabilitation Research, VA Connecticut Healthcare System, West Haven, CT 06516, USA
| | - Philip R Effraim
- Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT 06516, USA.,Center for Rehabilitation Research, VA Connecticut Healthcare System, West Haven, CT 06516, USA.,Department of Anesthesiology, Yale School of Medicine, New Haven, CT 06510, USA
| | - Stephen G Waxman
- Department of Neurology, Yale School of Medicine, New Haven, CT 06510, USA.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT 06516, USA.,Center for Rehabilitation Research, VA Connecticut Healthcare System, West Haven, CT 06516, USA
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8
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Le Cann K, Meents JE, Sudha Bhagavath Eswaran V, Dohrn MF, Bott R, Maier A, Bialer M, Hautvast P, Erickson A, Rolke R, Rothermel M, Körner J, Kurth I, Lampert A. Assessing the impact of pain-linked Nav1.7 variants: An example of two variants with no biophysical effect. Channels (Austin) 2021; 15:208-228. [PMID: 33487118 PMCID: PMC7833769 DOI: 10.1080/19336950.2020.1870087] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 12/23/2020] [Accepted: 12/23/2020] [Indexed: 11/30/2022] Open
Abstract
Mutations in the voltage-gated sodium channel Nav1.7 are linked to human pain. The Nav1.7/N1245S variant was described before in several patients suffering from primary erythromelalgia and/or olfactory hypersensitivity. We have identified this variant in a pain patient and a patient suffering from severe and life-threatening orthostatic hypotension. In addition, we report a female patient suffering from muscle pain and carrying the Nav1.7/E1139K variant. We tested both Nav1.7 variants by whole-cell voltage-clamp recordings in HEK293 cells, revealing a slightly enhanced current density for the N1245S variant when co-expressed with the β1 subunit. This effect was counteracted by an enhanced slow inactivation. Both variants showed similar voltage dependence of activation and steady-state fast inactivation, as well as kinetics of fast inactivation, deactivation, and use-dependency compared to WT Nav1.7. Finally, homology modeling revealed that the N1245S substitution results in different intramolecular interaction partners. Taken together, these experiments do not point to a clear pathogenic effect of either the N1245S or E1139K variant and suggest they may not be solely responsible for the patients' pain symptoms. As discussed previously for other variants, investigations in heterologous expression systems may not sufficiently mimic the pathophysiological situation in pain patients, and single nucleotide variants in other genes or modulatory proteins are necessary for these specific variants to show their effect. Our findings stress that biophysical investigations of ion channel mutations need to be evaluated with care and should preferably be supplemented with studies investigating the mutations in their context, ideally in human sensory neurons.
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Affiliation(s)
- Kim Le Cann
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Jannis E. Meents
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
| | | | - Maike F. Dohrn
- Department of Neurology, Medical Faculty, RWTH Aachen University Hospital, Aachen, Germany
| | - Raya Bott
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Andrea Maier
- Department of Neurology, Medical Faculty, RWTH Aachen University Hospital, Aachen, Germany
| | - Martin Bialer
- Division of Clinical Metabolism of Medical Genetics and Human Genomics at Northwell Health System, New-York, United States
| | - Petra Hautvast
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Andelain Erickson
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Roman Rolke
- Department for Palliative Care, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Markus Rothermel
- Department of Chemosensation, AG Neuromodulation, Institute for Biology II, RWTH Aachen University, Aachen, 52074, Germany
| | - Jannis Körner
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
- Department of Anaesthesiology, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Ingo Kurth
- Institute of Human Genetics, Medical Faculty, RWTH Aachen University Hospital, Aachen, Germany
| | - Angelika Lampert
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
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9
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Lybech LKM, Calabró M, Briuglia S, Drago A, Crisafulli C. Suicide Related Phenotypes in a Bipolar Sample: Genetic Underpinnings. Genes (Basel) 2021; 12:genes12101482. [PMID: 34680877 PMCID: PMC8535342 DOI: 10.3390/genes12101482] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 09/20/2021] [Accepted: 09/21/2021] [Indexed: 12/31/2022] Open
Abstract
Suicide in Bipolar Disorder (BD) is a relevant clinical concern. Genetics may shape the individual risk for suicide behavior in BD, together with known clinical factors. The lack of consistent replication in BD may be associated with its multigenetic component. In the present contribution we analyzed a sample of BD individuals (from STEP-BD database) to identify the genetic variants potentially associated with three different suicide-related phenotypes: (1) a feeling that the life was not worth living; (2) fantasies about committing a violent suicide; (3) previous attempted suicide. The sample under analysis included 1115 BD individuals. None of the SNPs reached genome-wide significance. However, a trend of association was evidenced for rs2767403, an intron variant of AOPEP gene, in association with phenotype #1 (p = 5.977 × 10−6). The molecular pathway analysis showed a significant enrichment in all the investigated phenotypes on pathways related to post synaptic signaling, neurotransmission and neurodevelopment. Further, NOTCH signaling or the γ-aminobutyric acid (GABA)-ergic signaling were found to be associated with specific suicide-related phenotypes. The present investigation contributes to the hypothesis that the genetic architecture of suicide behaviors in BD is related to alteration of entire pathways rather than single genes. In particular, our molecular pathway analysis points on some specific molecular events that could be the focus of further research in this field.
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Affiliation(s)
- Line K. M. Lybech
- Unit for Psychiatric Research, Psychiatry, Aalborg University Hospital, DK-9100 Aalborg, Denmark;
| | - Marco Calabró
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, 98125 Messina, Italy; (M.C.); (S.B.)
| | - Silvana Briuglia
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, 98125 Messina, Italy; (M.C.); (S.B.)
| | - Antonio Drago
- Unit for Psychiatric Research, Psychiatry, Aalborg University Hospital, DK-9100 Aalborg, Denmark;
- Correspondence: (A.D.); (C.C.); Tel.: +45-97-64-30-00 (A.D.); +39-(0)9-0221-3373 (C.C.)
| | - Concetta Crisafulli
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, 98125 Messina, Italy; (M.C.); (S.B.)
- Correspondence: (A.D.); (C.C.); Tel.: +45-97-64-30-00 (A.D.); +39-(0)9-0221-3373 (C.C.)
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10
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Takahashi K, Ohba T, Okamoto Y, Noguchi A, Okuda H, Kobayashi H, Harada KH, Koizumi A, Ono K, Takahashi T. E44Q mutation in Na V1.7 in a patient with infantile paroxysmal knee pain: electrophysiological analysis of voltage-dependent sodium current. Heliyon 2021; 7:e07396. [PMID: 34222704 PMCID: PMC8243507 DOI: 10.1016/j.heliyon.2021.e07396] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/21/2021] [Accepted: 06/21/2021] [Indexed: 10/31/2022] Open
Abstract
Gain-of-function mutations in voltage-gated sodium channels (NaV1.7, NaV1.8, and NaV1.9) are known causes of inherited pain disorders. Identification and functional assessment of new NaV1.7 mutations could help elucidate the phenotypic spectrum of NaV1.7 channelopathies. We identified a novel NaV1.7 mutation (E44Q in exon 2) that substitutes a glutamic acid residue for glutamine in the cytoplasmic N-terminus of NaV1.7 in a patient with paroxysmal pain attacks during childhood and his family who experienced similar pain episodes. To study the sodium channel's function, we performed electrophysiological recordings. Voltage-clamp recordings revealed that the mutation increased the amplitude of the non-inactivating component of the sodium current, which might facilitate channel opening. These data demonstrate that E44Q is a gain-of-function mutation in NaV1.7, which is consistent with our patient's pain phenotype.
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Affiliation(s)
- Kiichi Takahashi
- Department of Pediatrics, Akita University Graduate School of Medicine, 1-1-1, Hondo, Akita City, Akita, 010-8543, Japan
| | - Takayoshi Ohba
- Department of Cell Physiology, Akita University Graduate School of Medicine, 1-1-1, Hondo, Akita City, Akita, 010-8543, Japan
| | - Yosuke Okamoto
- Department of Cell Physiology, Akita University Graduate School of Medicine, 1-1-1, Hondo, Akita City, Akita, 010-8543, Japan
| | - Atsuko Noguchi
- Department of Pediatrics, Akita University Graduate School of Medicine, 1-1-1, Hondo, Akita City, Akita, 010-8543, Japan
| | - Hiroko Okuda
- Department of Pain Pharmacogenetics, Kyoto University Graduate School of Medicine, Yoshida Konoe, Sakyo, Kyoto, 606-8501, Japan
| | - Hatasu Kobayashi
- Department of Environmental and Molecular Medicine, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu, Mie, 514-8507, Japan
| | - Kouji H Harada
- Department of Health and Environmental Sciences, Kyoto University Graduate School of Medicine, Yoshida Konoe, Sakyo, Kyoto, 606-8501, Japan
| | - Akio Koizumi
- Institute of Public Health and Welfare Research, 18-13, Uzumasa Tanamori, Ukyo, Kyoto, 616-8141, Japan
| | - Kyoichi Ono
- Department of Cell Physiology, Akita University Graduate School of Medicine, 1-1-1, Hondo, Akita City, Akita, 010-8543, Japan
| | - Tsutomu Takahashi
- Department of Pediatrics, Akita University Graduate School of Medicine, 1-1-1, Hondo, Akita City, Akita, 010-8543, Japan
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11
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Xenakis MN, Kapetis D, Yang Y, Gerrits MM, Heijman J, Waxman SG, Lauria G, Faber CG, Westra RL, Lindsey PJ, Smeets HJ. Hydropathicity-based prediction of pain-causing NaV1.7 variants. BMC Bioinformatics 2021; 22:212. [PMID: 33892629 PMCID: PMC8063372 DOI: 10.1186/s12859-021-04119-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 04/01/2021] [Indexed: 11/10/2022] Open
Abstract
Background Mutation-induced variations in the functional architecture of the NaV1.7 channel protein are causally related to a broad spectrum of human pain disorders. Predicting in silico the phenotype of NaV1.7 variant is of major clinical importance; it can aid in reducing costs of in vitro pathophysiological characterization of NaV1.7 variants, as well as, in the design of drug agents for counteracting pain-disease symptoms. Results In this work, we utilize spatial complexity of hydropathic effects toward predicting which NaV1.7 variants cause pain (and which are neutral) based on the location of corresponding mutation sites within the NaV1.7 structure. For that, we analyze topological and scaling hydropathic characteristics of the atomic environment around NaV1.7’s pore and probe their spatial correlation with mutation sites. We show that pain-related mutation sites occupy structural locations in proximity to a hydrophobic patch lining the pore while clustering at a critical hydropathic-interactions distance from the selectivity filter (SF). Taken together, these observations can differentiate pain-related NaV1.7 variants from neutral ones, i.e., NaV1.7 variants not causing pain disease, with 80.5\documentclass[12pt]{minimal}
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\begin{document}$$\%$$\end{document}% specificity [area under the receiver operating characteristics curve = 0.872]. Conclusions Our findings suggest that maintaining hydrophobic NaV1.7 interior intact, as well as, a finely-tuned (dictated by hydropathic interactions) distance from the SF might be necessary molecular conditions for physiological NaV1.7 functioning. The main advantage for using the presented predictive scheme is its negligible computational cost, as well as, hydropathicity-based biophysical rationalization. Supplementary Information The online version contains supplementary material available at 10.1186/s12859-021-04119-2.
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Affiliation(s)
- Makros N Xenakis
- Department of Toxicogenomics, Section Clinical Genomics, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands. .,Research School for Mental Health and Neuroscience (MHeNS), Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands.
| | - Dimos Kapetis
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta", Via Celoria 11, 20133, Milan, Italy
| | - Yang Yang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University College of Pharmacy, West Lafayette, IN, 47907, USA.,Purdue Institute for Integrative Neuroscience, West Lafayette, IN, 47907, USA
| | - Monique M Gerrits
- Department of Clinical Genetics, Maastricht University Medical Center, PO box 5800, 6202 AZ, Maastricht, The Netherlands
| | - Jordi Heijman
- Department of Cardiology, CARIM School for Cardiovascular Diseases, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
| | - Stephen G Waxman
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, 06510, USA.,Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, 06516, USA
| | - Giuseppe Lauria
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta", Via Celoria 11, 20133, Milan, Italy.,Department of Biomedical and Clinical Sciences "Luigi Sacco", University of Milan, Via G.B. Grassi 74, 20157, Milan, Italy
| | - Catharina G Faber
- Department of Neurology, Maastricht University Medical Center, PO Box 5800, 6202 AZ, Maastricht, The Netherlands
| | - Ronald L Westra
- Department of Data Science and Knowledge Engineering, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
| | - Patrick J Lindsey
- Department of Toxicogenomics, Section Clinical Genomics, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands.,Research School for Oncology and Developmental Biology (GROW), Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
| | - Hubert J Smeets
- Department of Toxicogenomics, Section Clinical Genomics, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands.,Research School for Mental Health and Neuroscience (MHeNS), Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
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12
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Schutte SC, Kadakia F, Davidson S. Skin-Nerve Co-Culture Systems for Disease Modeling and Drug Discovery. Tissue Eng Part C Methods 2021; 27:89-99. [PMID: 33349133 DOI: 10.1089/ten.tec.2020.0296] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Prominent clinical problems related to the skin-nerve interface include barrier dysfunction and erythema, but it is the symptoms of pain and itch that most often lead patients to seek medical treatment. Tissue-engineered innervated skin models provide an excellent solution for studying the mechanisms underlying neurocutaneous disorders for drug screening, and cutaneous device development. Innervated skin substitutes provide solutions beyond traditional monolayer cultures and have advantages that make them preferable to in vivo animal studies for certain applications, such as measuring somatosensory transduction. The tissue-engineered innervated skin models replicate the complex stratified epidermis that provides barrier function in native skin, a feature that is lacking in monolayer co-cultures, while allowing for a level of detail in measurement of nerve morphology and function that cannot be achieved in animal models. In this review, the advantages and disadvantages of different cell sources and scaffold materials will be discussed and a presentation of the current state of the field is reviewed. Impact statement A review of the current state of innervated skin substitutes and the considerations that need to be addressed when developing these models. Tissue-engineered skin substitutes are customizable and provide barrier function allowing for screening of topical drugs and for studying nerve function.
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Affiliation(s)
- Stacey C Schutte
- Department of Biomedical Engineering, University of Cincinnati, Cincinnati, Ohio, USA
| | - Feni Kadakia
- Department of Anesthesiology, Pain Research Center, and Neuroscience Graduate Program, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Steve Davidson
- Department of Anesthesiology, Pain Research Center, and Neuroscience Graduate Program, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
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13
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Kerth CM, Hautvast P, Körner J, Lampert A, Meents JE. Phosphorylation of a chronic pain mutation in the voltage-gated sodium channel Nav1.7 increases voltage sensitivity. J Biol Chem 2021; 296:100227. [PMID: 33361158 PMCID: PMC7948457 DOI: 10.1074/jbc.ra120.014288] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 12/17/2020] [Accepted: 12/22/2020] [Indexed: 12/19/2022] Open
Abstract
Mutations in voltage-gated sodium channels (Navs) can cause alterations in pain sensation, such as chronic pain diseases like inherited erythromelalgia. The mutation causing inherited erythromelalgia, Nav1.7 p.I848T, is known to induce a hyperpolarized shift in the voltage dependence of activation in Nav1.7. So far, however, the mechanism to explain this increase in voltage sensitivity remains unknown. In the present study, we show that phosphorylation of the newly introduced Thr residue explains the functional change. We expressed wildtype human Nav1.7, the I848T mutant, or other mutations in HEK293T cells and performed whole-cell patch-clamp electrophysiology. As the insertion of a Thr residue potentially creates a novel phosphorylation site for Ser/Thr kinases and because Nav1.7 had been shown in Xenopus oocytes to be affected by protein kinases C and A, we used different nonselective and selective kinase inhibitors and activators to test the effect of phosphorylation on Nav1.7 in a human system. We identify protein kinase C, but not protein kinase A, to be responsible for the phosphorylation of T848 and thereby for the shift in voltage sensitivity. Introducing a negatively charged amino acid instead of the putative phosphorylation site mimics the effect on voltage gating to a lesser extent. 3D modeling using the published cryo-EM structure of human Nav1.7 showed that introduction of this negatively charged site seems to alter the interaction of this residue with the surrounding amino acids and thus to influence channel function. These results could provide new opportunities for the development of novel treatment options for patients with chronic pain.
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Affiliation(s)
- Clara M Kerth
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Petra Hautvast
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Jannis Körner
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany; Department of Anesthesiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Angelika Lampert
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Jannis E Meents
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany.
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14
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Abstract
Primary nociceptors are a heterogeneous class of peripheral somatosensory neurons, responsible for detecting noxious, pruriceptive, and thermal stimuli. These neurons are further divided into several molecularly defined subtypes that correlate with their functional sensory modalities and morphological features. During development, all nociceptors arise from a common pool of embryonic precursors, and then segregate progressively into their mature specialized phenotypes. In this review, we summarize the intrinsic transcriptional programs and extrinsic trophic factor signaling mechanisms that interact to control nociceptor diversification. We also discuss how recent transcriptome profiling studies have significantly advanced the field of sensory neuron development.
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Affiliation(s)
- Suna L Cranfill
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Wenqin Luo
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States.
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15
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Toffano AA, Chiarot G, Zamuner S, Marchi M, Salvi E, Waxman SG, Faber CG, Lauria G, Giacometti A, Simeoni M. Computational pipeline to probe NaV1.7 gain-of-function variants in neuropathic painful syndromes. Sci Rep 2020; 10:17930. [PMID: 33087732 PMCID: PMC7578092 DOI: 10.1038/s41598-020-74591-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 09/30/2020] [Indexed: 01/09/2023] Open
Abstract
Applications of machine learning and graph theory techniques to neuroscience have witnessed an increased interest in the last decade due to the large data availability and unprecedented technology developments. Their employment to investigate the effect of mutational changes in genes encoding for proteins modulating the membrane of excitable cells, whose biological correlates are assessed at electrophysiological level, could provide useful predictive clues. We apply this concept to the analysis of variants in sodium channel NaV1.7 subunit found in patients with chronic painful syndromes, by the implementation of a dedicated computational pipeline empowering different and complementary techniques including homology modeling, network theory, and machine learning. By testing three templates of different origin and sequence identities, we provide an optimal condition for its use. Our findings reveal the usefulness of our computational pipeline in supporting the selection of candidates for cell electrophysiology assay and with potential clinical applications.
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Affiliation(s)
- Alberto A Toffano
- Dipartimento di Scienze Molecolari e Nanosistemi, Universitá Ca' Foscari Venezia, Venezia-Mestre, Italy
| | - Giacomo Chiarot
- Dipartimento di Scienze Ambientali, Informatica e Statistica, Universitá Ca' Foscari Venezia, Venezia-Mestre, Italy
| | - Stefano Zamuner
- Laboratory of Statistical Biophysics, Institute of Physics, School of Basic Sciences, Ècole Polytechnique Fèdèrale de Lausanne (EPFL), Lausanne, Switzerland
| | - Margherita Marchi
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta", Milan, Italy
| | - Erika Salvi
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta", Milan, Italy
| | - Stephen G Waxman
- Center for Neuroscience and Regeneration Research, VA Connecticut Healthcare System and Yale Medical School, West Haven, USA
| | - Catharina G Faber
- MHeNs school for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.,Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Giuseppe Lauria
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta", Milan, Italy.,Department of Biomedical and Clinical Sciences "Luigi Sacco", University of Milan, Milan, Italy
| | - Achille Giacometti
- Dipartimento di Scienze Molecolari e Nanosistemi, Universitá Ca' Foscari Venezia, Venezia-Mestre, Italy.,European Centre for Living Technology (ECLT), Venice, Italy
| | - Marta Simeoni
- Dipartimento di Scienze Ambientali, Informatica e Statistica, Universitá Ca' Foscari Venezia, Venezia-Mestre, Italy. .,European Centre for Living Technology (ECLT), Venice, Italy.
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16
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Menezes LFS, Sabiá Júnior EF, Tibery DV, Carneiro LDA, Schwartz EF. Epilepsy-Related Voltage-Gated Sodium Channelopathies: A Review. Front Pharmacol 2020; 11:1276. [PMID: 33013363 PMCID: PMC7461817 DOI: 10.3389/fphar.2020.01276] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 07/31/2020] [Indexed: 12/29/2022] Open
Abstract
Epilepsy is a disease characterized by abnormal brain activity and a predisposition to generate epileptic seizures, leading to neurobiological, cognitive, psychological, social, and economic impacts for the patient. There are several known causes for epilepsy; one of them is the malfunction of ion channels, resulting from mutations. Voltage-gated sodium channels (NaV) play an essential role in the generation and propagation of action potential, and malfunction caused by mutations can induce irregular neuronal activity. That said, several genetic variations in NaV channels have been described and associated with epilepsy. These mutations can affect channel kinetics, modifying channel activation, inactivation, recovery from inactivation, and/or the current window. Among the NaV subtypes related to epilepsy, NaV1.1 is doubtless the most relevant, with more than 1500 mutations described. Truncation and missense mutations are the most observed alterations. In addition, several studies have already related mutated NaV channels with the electrophysiological functioning of the channel, aiming to correlate with the epilepsy phenotype. The present review provides an overview of studies on epilepsy-associated mutated human NaV1.1, NaV1.2, NaV1.3, NaV1.6, and NaV1.7.
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Affiliation(s)
- Luis Felipe Santos Menezes
- Laboratório de Neurofarmacologia, Departamento de Ciências Fisiológicas, Universidade de Brasília, Brasília, Brazil
| | - Elias Ferreira Sabiá Júnior
- Laboratório de Neurofarmacologia, Departamento de Ciências Fisiológicas, Universidade de Brasília, Brasília, Brazil
| | - Diogo Vieira Tibery
- Laboratório de Neurofarmacologia, Departamento de Ciências Fisiológicas, Universidade de Brasília, Brasília, Brazil
| | - Lilian Dos Anjos Carneiro
- Faculdade de Medicina, Centro Universitário Euro Americano, Brasília, Brazil.,Faculdade de Medicina, Centro Universitário do Planalto Central, Brasília, Brazil
| | - Elisabeth Ferroni Schwartz
- Laboratório de Neurofarmacologia, Departamento de Ciências Fisiológicas, Universidade de Brasília, Brasília, Brazil
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17
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Painful and painless mutations of SCN9A and SCN11A voltage-gated sodium channels. Pflugers Arch 2020; 472:865-880. [PMID: 32601768 PMCID: PMC7351857 DOI: 10.1007/s00424-020-02419-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 05/25/2020] [Accepted: 06/10/2020] [Indexed: 12/11/2022]
Abstract
Chronic pain is a global problem affecting up to 20% of the world’s population and has a significant economic, social and personal cost to society. Sensory neurons of the dorsal root ganglia (DRG) detect noxious stimuli and transmit this sensory information to regions of the central nervous system (CNS) where activity is perceived as pain. DRG neurons express multiple voltage-gated sodium channels that underlie their excitability. Research over the last 20 years has provided valuable insights into the critical roles that two channels, NaV1.7 and NaV1.9, play in pain signalling in man. Gain of function mutations in NaV1.7 cause painful conditions while loss of function mutations cause complete insensitivity to pain. Only gain of function mutations have been reported for NaV1.9. However, while most NaV1.9 mutations lead to painful conditions, a few are reported to cause insensitivity to pain. The critical roles these channels play in pain along with their low expression in the CNS and heart muscle suggest they are valid targets for novel analgesic drugs.
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18
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The role of Nav1.7 in human nociceptors: insights from human induced pluripotent stem cell-derived sensory neurons of erythromelalgia patients. Pain 2020; 160:1327-1341. [PMID: 30720580 PMCID: PMC6554007 DOI: 10.1097/j.pain.0000000000001511] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Supplemental Digital Content is Available in the Text. Human sodium channel NaV1.7 in induced pluripotent stem cell–derived sensory neurons sets the action potential threshold but does not support subthreshold depolarizations. The chronic pain syndrome inherited erythromelalgia (IEM) is attributed to mutations in the voltage-gated sodium channel (NaV) 1.7. Still, recent studies targeting NaV1.7 in clinical trials have provided conflicting results. Here, we differentiated induced pluripotent stem cells from IEM patients with the NaV1.7/I848T mutation into sensory nociceptors. Action potentials in these IEM nociceptors displayed a decreased firing threshold, an enhanced upstroke, and afterhyperpolarization, all of which may explain the increased pain experienced by patients. Subsequently, we investigated the voltage dependence of the tetrodotoxin-sensitive NaV activation in these human sensory neurons using a specific prepulse voltage protocol. The IEM mutation induced a hyperpolarizing shift of NaV activation, which leads to activation of NaV1.7 at more negative potentials. Our results indicate that NaV1.7 is not active during subthreshold depolarizations, but that its activity defines the action potential threshold and contributes significantly to the action potential upstroke. Thus, our model system with induced pluripotent stem cell–derived sensory neurons provides a new rationale for NaV1.7 function and promises to be valuable as a translational tool to profile and develop more efficacious clinical analgesics.
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19
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Patel P, Zhang Y, Unikel LH, Edwards C. A case of sporadic erythromelalgia presenting with small fibre neuropathy. BMJ Case Rep 2019; 12:12/10/e230549. [PMID: 31601551 DOI: 10.1136/bcr-2019-230549] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Erythromelalgia (EM) is a rare disorder of small nerve fibres that leads to painful flushing and burning paresthesisas of the distal extremities and is typically associated with heat or physical activity; relief is found using cooling measures. Its effects are often debilitating in the general population, but this patient had an excellent response to specific treatment options and continues to maintain employment, something many individuals suffering from EM are unable to do. His presentation was also unique in that he had isolated, proximal involvement as his condition progressed whereas typically only the distal extremities are affected. Routine electromyography and nerve conduction studies were normal, whereas nerve biopsy demonstrated findings of small fibre neuropathy. Ultimately, his condition was managed with carbamazepine and his symptoms have almost entirely resolved to date.
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Affiliation(s)
- Pavan Patel
- Neurology, Albert Einstein Medical Center, Philadelphia, PA, USA
| | - Yan Zhang
- Neurology, Albert Einstein Medical Center, Philadelphia, PA, USA
| | - Lynne H Unikel
- Neurology, Albert Einstein Medical Center, Philadelphia, PA, USA
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20
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Ciotu CI, Tsantoulas C, Meents J, Lampert A, McMahon SB, Ludwig A, Fischer MJM. Noncanonical Ion Channel Behaviour in Pain. Int J Mol Sci 2019; 20:E4572. [PMID: 31540178 PMCID: PMC6770626 DOI: 10.3390/ijms20184572] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 09/09/2019] [Accepted: 09/12/2019] [Indexed: 12/19/2022] Open
Abstract
Ion channels contribute fundamental properties to cell membranes. Although highly diverse in conductivity, structure, location, and function, many of them can be regulated by common mechanisms, such as voltage or (de-)phosphorylation. Primarily considering ion channels involved in the nociceptive system, this review covers more novel and less known features. Accordingly, we outline noncanonical operation of voltage-gated sodium, potassium, transient receptor potential (TRP), and hyperpolarization-activated cyclic nucleotide (HCN)-gated channels. Noncanonical features discussed include properties as a memory for prior voltage and chemical exposure, alternative ion conduction pathways, cluster formation, and silent subunits. Complementary to this main focus, the intention is also to transfer knowledge between fields, which become inevitably more separate due to their size.
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Affiliation(s)
- Cosmin I Ciotu
- Center for Physiology and Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | | | - Jannis Meents
- Institute of Physiology, University Hospital RWTH Aachen, 52074 Aachen, Germany
| | - Angelika Lampert
- Institute of Physiology, University Hospital RWTH Aachen, 52074 Aachen, Germany
| | - Stephen B McMahon
- Wolfson Centre for Age-Related Diseases, King's College London, London SE1 1UR, UK
| | - Andreas Ludwig
- Institute of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Michael J M Fischer
- Center for Physiology and Pharmacology, Medical University of Vienna, 1090 Vienna, Austria.
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21
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Abstract
Acute pain is adaptive, but chronic pain is a global challenge. Many chronic pain syndromes are peripheral in origin and reflect hyperactivity of peripheral pain-signaling neurons. Current treatments are ineffective or only partially effective and in some cases can be addictive, underscoring the need for better therapies. Molecular genetic studies have now linked multiple human pain disorders to voltage-gated sodium channels, including disorders characterized by insensitivity or reduced sensitivity to pain and others characterized by exaggerated pain in response to normally innocuous stimuli. Here, we review recent developments that have enhanced our understanding of pathophysiological mechanisms in human pain and advances in targeting sodium channels in peripheral neurons for the treatment of pain using novel and existing sodium channel blockers.
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Affiliation(s)
- Sulayman D Dib-Hajj
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510, USA; .,Rehabilitation Research Center, Veterans Affairs, Connecticut Healthcare System, West Haven, Connecticut 06516, USA
| | - Stephen G Waxman
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510, USA; .,Rehabilitation Research Center, Veterans Affairs, Connecticut Healthcare System, West Haven, Connecticut 06516, USA
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22
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Bennett DL, Clark AJ, Huang J, Waxman SG, Dib-Hajj SD. The Role of Voltage-Gated Sodium Channels in Pain Signaling. Physiol Rev 2019; 99:1079-1151. [DOI: 10.1152/physrev.00052.2017] [Citation(s) in RCA: 256] [Impact Index Per Article: 51.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Acute pain signaling has a key protective role and is highly evolutionarily conserved. Chronic pain, however, is maladaptive, occurring as a consequence of injury and disease, and is associated with sensitization of the somatosensory nervous system. Primary sensory neurons are involved in both of these processes, and the recent advances in understanding sensory transduction and human genetics are the focus of this review. Voltage-gated sodium channels (VGSCs) are important determinants of sensory neuron excitability: they are essential for the initial transduction of sensory stimuli, the electrogenesis of the action potential, and neurotransmitter release from sensory neuron terminals. Nav1.1, Nav1.6, Nav1.7, Nav1.8, and Nav1.9 are all expressed by adult sensory neurons. The biophysical characteristics of these channels, as well as their unique expression patterns within subtypes of sensory neurons, define their functional role in pain signaling. Changes in the expression of VGSCs, as well as posttranslational modifications, contribute to the sensitization of sensory neurons in chronic pain states. Furthermore, gene variants in Nav1.7, Nav1.8, and Nav1.9 have now been linked to human Mendelian pain disorders and more recently to common pain disorders such as small-fiber neuropathy. Chronic pain affects one in five of the general population. Given the poor efficacy of current analgesics, the selective expression of particular VGSCs in sensory neurons makes these attractive targets for drug discovery. The increasing availability of gene sequencing, combined with structural modeling and electrophysiological analysis of gene variants, also provides the opportunity to better target existing therapies in a personalized manner.
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Affiliation(s)
- David L. Bennett
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Alex J. Clark
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Jianying Huang
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Stephen G. Waxman
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Sulayman D. Dib-Hajj
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
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23
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Pediatric Erythromelalgia and SCN9A Mutations: Systematic Review and Single-Center Case Series. J Pediatr 2019; 206:217-224.e9. [PMID: 30416015 DOI: 10.1016/j.jpeds.2018.10.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 09/07/2018] [Accepted: 10/11/2018] [Indexed: 12/19/2022]
Abstract
OBJECTIVES To evaluate the clinical features of erythromelalgia in childhood associated with gain-of-function SCN9A mutations that increase activity of the Nav1.7 voltage-gated sodium channel, we conducted a systematic review of pediatric presentations of erythromelalgia related to SCN9A mutations, and compared pediatric clinical presentations of symptomatic erythromelalgia, with or without SCN9A mutations. STUDY DESIGN PubMed, Embase, and PsycINFO Databases were searched for reports of inherited erythromelalgia in childhood. Clinical features, management, and genotype were extracted. Case notes of pediatric patients with erythromelalgia from the Great Ormond Street Hospital Pain Service were reviewed for clinical features, patient-reported outcomes, and treatments. Children aged over 10 years were recruited for quantitative sensory testing. RESULTS Twenty-eight publications described erythromelalgia associated with 15 different SCN9A gene variants in 25 children. Pain was severe and often refractory to multiple treatments, including nonspecific sodium channel blockers. Skin damage or other complications of cold immersion for symptomatic relief were common (60%). SCN9A mutations resulting in greater hyperpolarizing shifts in Nav1.7 sodium channels correlated with symptom onset at younger ages (P = .016). Variability in reporting, and potential publication bias toward severe cases, limit any estimations of overall prevalence. In our case series, symptoms were similar but comorbidities were more common in children with SCN9A mutations. Quantitative sensory testing revealed marked dynamic warm allodynia. CONCLUSIONS Inherited erythromelalgia in children is associated with difficult-to-manage pain and significant morbidity. Standardized reporting of outcome and management in larger series will strengthen identification of genotype-phenotype relationships. More effective long-term therapies are a significant unmet clinical need.
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24
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Shen H, Liu D, Wu K, Lei J, Yan N. Structures of human Na v1.7 channel in complex with auxiliary subunits and animal toxins. Science 2019; 363:1303-1308. [PMID: 30765606 DOI: 10.1126/science.aaw2493] [Citation(s) in RCA: 288] [Impact Index Per Article: 57.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Accepted: 01/29/2019] [Indexed: 12/18/2022]
Abstract
Voltage-gated sodium channel Nav1.7 represents a promising target for pain relief. Here we report the cryo-electron microscopy structures of the human Nav1.7-β1-β2 complex bound to two combinations of pore blockers and gating modifier toxins (GMTs), tetrodotoxin with protoxin-II and saxitoxin with huwentoxin-IV, both determined at overall resolutions of 3.2 angstroms. The two structures are nearly identical except for minor shifts of voltage-sensing domain II (VSDII), whose S3-S4 linker accommodates the two GMTs in a similar manner. One additional protoxin-II sits on top of the S3-S4 linker in VSDIV The structures may represent an inactivated state with all four VSDs "up" and the intracellular gate closed. The structures illuminate the path toward mechanistic understanding of the function and disease of Nav1.7 and establish the foundation for structure-aided development of analgesics.
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Affiliation(s)
- Huaizong Shen
- State Key Laboratory of Membrane Biology, Tsinghua University, Beijing 100084, China.,Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China.,Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China
| | - Dongliang Liu
- State Key Laboratory of Membrane Biology, Tsinghua University, Beijing 100084, China.,Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China.,Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China
| | - Kun Wu
- Medical Research Center, Beijing Key Laboratory of Cardiopulmonary Cerebral Resuscitation, Beijing Chao-Yang Hospital, Capital Medical University, Beijing 100020, China
| | - Jianlin Lei
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China.,Technology Center for Protein Sciences, Ministry of Education Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Nieng Yan
- State Key Laboratory of Membrane Biology, Tsinghua University, Beijing 100084, China. .,Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing 100084, China.,Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences and School of Medicine, Tsinghua University, Beijing 100084, China
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25
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Sensitized vasoactive C-nociceptors: key fibers in peripheral neuropathic pain. Pain Rep 2019; 4:e709. [PMID: 30801047 PMCID: PMC6370139 DOI: 10.1097/pr9.0000000000000709] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 11/26/2018] [Accepted: 12/05/2018] [Indexed: 12/28/2022] Open
Abstract
Introduction Multiple mechanisms are involved in the development and persistence of neuropathic pain. Some patients with nerve damage will remain painless and develop a "loss of function" phenotype, whereas others develop painful neuropathies. Objectives The aim of this study is to investigate the role of a peripheral nervous system sensitization by analyzing patients with and without pain. Methods The topical application of capsaicin was investigated in peripheral nociceptors. Two groups of patients (painful vs painless) with length-dependent neuropathies and small-fiber impairment were tested. Quantitative sensory testing was assessed before and after topical application of 0.6% capsaicin in the affected skin. In addition, blood perfusion measurements and an axon reflex flare assessment were performed. Results Quantitative testing revealed that heat hyperalgesia was induced in all patients and volunteers (P < 0.01) without observing any significant differences between patient groups. By contrast, the extent of the axon reflex flare reaction (P < 0.01) as well as the blood perfusion (P < 0.05) was significantly greater in patients with pain than in neuropathy patients not experiencing pain. Conclusion Hyperexcitable vasoactive nociceptive C fibers might contribute to pain in peripheral neuropathies and therefore may serve as a key player in separating into a painless or painful condition.
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26
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Sopacua M, Hoeijmakers JGJ, Merkies ISJ, Lauria G, Waxman SG, Faber CG. Small‐fiber neuropathy: Expanding the clinical pain universe. J Peripher Nerv Syst 2019; 24:19-33. [DOI: 10.1111/jns.12298] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 11/27/2018] [Accepted: 12/14/2018] [Indexed: 12/11/2022]
Affiliation(s)
- Maurice Sopacua
- Department of Neurology, School of Mental Health and NeuroscienceMaastricht University Medical Centre+ Maastricht The Netherlands
| | - Janneke G. J. Hoeijmakers
- Department of Neurology, School of Mental Health and NeuroscienceMaastricht University Medical Centre+ Maastricht The Netherlands
| | - Ingemar S. J. Merkies
- Department of Neurology, School of Mental Health and NeuroscienceMaastricht University Medical Centre+ Maastricht The Netherlands
- Department of NeurologySt. Elisabeth Hospital Willemstad Curaçao
| | - Giuseppe Lauria
- Neuroalgology UnitIRCCS Foundation, “Carlo Besta” Neurological Institute Milan Italy
- Department of Biomedical and Clinical Sciences “Luigi Sacco”University of Milan Milan Italy
| | - Stephen G. Waxman
- Department of NeurologyYale University School of Medicine New Haven Connecticut
- Center for Neuroscience and Regeneration ResearchVA Connecticut Healthcare System West Haven Connecticut
| | - Catharina G. Faber
- Department of Neurology, School of Mental Health and NeuroscienceMaastricht University Medical Centre+ Maastricht The Netherlands
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27
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Insensitivity to Pain upon Adult-Onset Deletion of Nav1.7 or Its Blockade with Selective Inhibitors. J Neurosci 2018; 38:10180-10201. [PMID: 30301756 DOI: 10.1523/jneurosci.1049-18.2018] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 09/13/2018] [Accepted: 09/29/2018] [Indexed: 11/21/2022] Open
Abstract
Strong human genetic evidence points to an essential contribution of the voltage-gated sodium channel Nav1.7 to pain sensation: loss of Nav1.7 function leads to congenital insensitivity to pain, whereas gain-of-function mutations in the SCN9A gene that encodes Nav1.7 cause painful neuropathies, such as inherited erythromelalgia, a syndrome characterized by episodic spontaneous pain. Selective Nav1.7 channel blockers thus hold promise as potential painkillers with improved safety and reduced unwanted side effects compared with existing therapeutics. To determine the maximum effect of a theoretically perfectly selective Nav1.7 inhibitor, we generated a tamoxifen-inducible KO mouse model enabling genetic deletion of Nav1.7 from adult mice. Electrophysiological recordings of sensory neurons from these mice following tamoxifen injection demonstrated the loss of Nav1.7 channel current and the resulting decrease in neuronal excitability of small-diameter neurons. We found that behavioral responses to most, but surprisingly not all, modalities of noxious stimulus are abolished following adult deletion of Nav1.7, pointing toward indications where Nav1.7 blockade should be efficacious. Furthermore, we demonstrate that isoform-selective acylsulfonamide Nav1.7 inhibitors show robust analgesic and antinociceptive activity acutely after a single dose in mouse pain models shown to be Nav1.7-dependent. All experiments were done with both male and female mice. Collectively, these data expand the depth of knowledge surrounding Nav1.7 biology as it relates to pain, and provide preclinical proof of efficacy that lays a clear path toward translation for the therapeutic use of Nav1.7-selective inhibitors in humans.SIGNIFICANCE STATEMENT Loss-of-function mutations in the sodium channel Nav1.7 cause congenital insensitivity to pain in humans, making Nav1.7 a top target for novel pain drugs. Targeting Nav1.7 selectively has been challenging, however, in part due to uncertainties in which rodent pain models are dependent on Nav1.7. We have developed and characterized an adult-onset Nav1.7 KO mouse model that allows us to determine the expected effects of a theoretically perfect Nav1.7 blocker. Importantly, many commonly used pain models, such as mechanical allodynia after nerve injury, appear to not be dependent on Nav1.7 in the adult. By defining which models are Nav1.7 dependent, we demonstrate that selective Nav1.7 inhibitors can approximate the effects of genetic loss of function, which previously has not been directly established.
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28
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Themistocleous AC, Crombez G, Baskozos G, Bennett DL. Using stratified medicine to understand, diagnose, and treat neuropathic pain. Pain 2018; 159 Suppl 1:S31-S42. [PMID: 30113945 PMCID: PMC6130809 DOI: 10.1097/j.pain.0000000000001301] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
| | - Geert Crombez
- Department of Experimental-Clinical and Health Psychology, Ghent University, Ghent, Belgium
| | - Georgios Baskozos
- The Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - David L Bennett
- The Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
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29
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Selective NaV1.7 Antagonists with Long Residence Time Show Improved Efficacy against Inflammatory and Neuropathic Pain. Cell Rep 2018; 24:3133-3145. [DOI: 10.1016/j.celrep.2018.08.063] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 06/26/2018] [Accepted: 08/22/2018] [Indexed: 11/21/2022] Open
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30
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Abstract
In the contemporary era of medical diagnosis via sophisticated radiographic imaging and/or comprehensive serological testing, a focused physical examination remains paramount in recognizing the cutaneous manifestations of chronic vascular disease. Recognition of the unique cutaneous signs of lymphatic and venous hypertension assists in the diagnosis as well as the staging and classification of both lymphedema and chronic venous insufficiency. Awareness of explicit dermatologic vasomotor manifestations aids not only in the identification of acrocyanosis, Raynaud phenomenon, pernio, and erythromelalgia but also mitigates confusion related to their clinical overlap. Although the clinical signs of peripheral artery disease are not necessarily specific or sensitive, a knowledge of suggestive dermatologic findings is helpful in recognition of severe limb ischemia. A brief review of the epidemiology, etiology, pathogenesis, and therapy of cutaneous related chronic vascular disease follows including an emphasis on characteristic clinical features supported by illustrative photographs.
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Affiliation(s)
- Steven M Dean
- Division of Cardiovascular Medicine, Ohio State University Wexner Medical Center, Columbus, OH.
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31
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Na V 1.7 as a Pharmacogenomic Target for Pain: Moving Toward Precision Medicine. Trends Pharmacol Sci 2018; 39:258-275. [DOI: 10.1016/j.tips.2017.11.010] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 11/27/2017] [Accepted: 11/29/2017] [Indexed: 01/15/2023]
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32
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Zorina-Lichtenwalter K, Parisien M, Diatchenko L. Genetic studies of human neuropathic pain conditions: a review. Pain 2018; 159:583-594. [PMID: 29240606 PMCID: PMC5828382 DOI: 10.1097/j.pain.0000000000001099] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2017] [Revised: 10/20/2017] [Accepted: 10/26/2017] [Indexed: 12/12/2022]
Abstract
Numerous studies have shown associations between genetic variants and neuropathic pain disorders. Rare monogenic disorders are caused by mutations of substantial effect size in a single gene, whereas common disorders are likely to have a contribution from multiple genetic variants of mild effect size, representing different biological pathways. In this review, we survey the reported genetic contributors to neuropathic pain and submit them for validation in a 150,000-participant sample of the U.K. Biobank cohort. Successfully replicated association with a neuropathic pain construct for 2 variants in IL10 underscores the importance of neuroimmune interactions, whereas genome-wide significant association with low back pain (P = 1.3e-8) and false discovery rate 5% significant associations with hip, knee, and neck pain for variant rs7734804 upstream of the MAT2B gene provide evidence of shared contributing mechanisms to overlapping pain conditions at the molecular genetic level.
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Affiliation(s)
| | - Marc Parisien
- Alan Edwards Pain Centre, McGill University, Montreal, QC, Canada
| | - Luda Diatchenko
- Alan Edwards Pain Centre, McGill University, Montreal, QC, Canada
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33
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Huang J, Mis MA, Tanaka B, Adi T, Estacion M, Liu S, Walker S, Dib-Hajj SD, Waxman SG. Atypical changes in DRG neuron excitability and complex pain phenotype associated with a Na v1.7 mutation that massively hyperpolarizes activation. Sci Rep 2018; 8:1811. [PMID: 29379075 PMCID: PMC5788866 DOI: 10.1038/s41598-018-20221-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 01/16/2018] [Indexed: 02/06/2023] Open
Abstract
Sodium channel Nav1.7 plays a central role in pain-signaling: gain-of-function Nav1.7 mutations usually cause severe pain and loss-of-function mutations produce insensitivity to pain. The Nav1.7 I234T gain-of-function mutation, however, is linked to a dual clinical presentation of episodic pain, together with absence of pain following fractures, and corneal anesthesia. How a Nav1.7 mutation that produces gain-of-function at the channel level causes clinical loss-of-function has remained enigmatic. We show by current-clamp that expression of I234T in dorsal root ganglion (DRG) neurons produces a range of membrane depolarizations including a massive shift to >−40 mV that reduces excitability in a small number of neurons. Dynamic-clamp permitted us to mimic the heterozygous condition via replacement of 50% endogenous wild-type Nav1.7 channels by I234T, and confirmed that the I234T conductance could drastically depolarize DRG neurons, resulting in loss of excitability. We conclude that attenuation of pain sensation by I234T is caused by massively depolarized membrane potential of some DRG neurons which is partly due to enhanced overlap between activation and fast-inactivation, impairing their ability to fire. Our results demonstrate how a Nav1.7 mutation that produces channel gain-of-function can contribute to a dual clinical presentation that includes loss of pain sensation at the clinical level.
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Affiliation(s)
- Jianying Huang
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA, 06510.,Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA, 06516
| | - Malgorzata A Mis
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA, 06510.,Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA, 06516
| | - Brian Tanaka
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA, 06510.,Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA, 06516
| | - Talia Adi
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA, 06510.,Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA, 06516
| | - Mark Estacion
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA, 06510.,Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA, 06516
| | - Shujun Liu
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA, 06510.,Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA, 06516
| | - Suellen Walker
- Developmental Neurosciences Program, Department of Anaesthesia and Pain Medicine, UCL Great Ormond Street Hospital, London, WC1N 1EH, UK
| | - Sulayman D Dib-Hajj
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA, 06510.,Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA, 06516
| | - Stephen G Waxman
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA, 06510. .,Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA, 06516.
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34
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Abstract
The low prevalence of erythromelalgia, classified as an orphan disease, poses diagnostic and therapeutic difficulties. The aim of this review is to be an update of the specialized bibliography. Erythromelalgia is an infrequent episodic acrosyndrome affecting mainly both lower limbs symmetrically with the classic triad of erythema, warmth and burning pain. Primary erythromelalgia is an autosomal dominant inherited disorder, while secondary is associated with myeloproliferative diseases, among others. In its etiopathogenesis, there are neural and vascular abnormalities that can be combined. The diagnosis is based on exhaustive clinical history and physical examination. Complications are due to changes in the skin barrier function, ischemia and compromise of cutaneous nerves. Because of the complexity of its pathogenesis, erythromelalgia should always be included in the differential diagnosis of conditions that cause chronic pain and/or peripheral edema. The prevention of crisis is based on a strict control of triggers and promotion of preventive measures. Since there is no specific and effective treatment, control should focus on the underlying disease. However, there are numerous topical and systemic therapies that patients can benefit from.
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35
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Q10R mutation in SCN9A gene is associated with generalized epilepsy with febrile seizures plus. Seizure 2017; 50:186-188. [PMID: 28704742 DOI: 10.1016/j.seizure.2017.06.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 06/07/2017] [Accepted: 06/28/2017] [Indexed: 11/21/2022] Open
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36
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Huang J, Vanoye CG, Cutts A, Goldberg YP, Dib-Hajj SD, Cohen CJ, Waxman SG, George AL. Sodium channel NaV1.9 mutations associated with insensitivity to pain dampen neuronal excitability. J Clin Invest 2017; 127:2805-2814. [PMID: 28530638 DOI: 10.1172/jci92373] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 03/23/2017] [Indexed: 02/05/2023] Open
Abstract
Voltage-gated sodium channel (NaV) mutations cause genetic pain disorders that range from severe paroxysmal pain to a congenital inability to sense pain. Previous studies on NaV1.7 and NaV1.8 established clear relationships between perturbations in channel function and divergent clinical phenotypes. By contrast, studies of NaV1.9 mutations have not revealed a clear relationship of channel dysfunction with the associated and contrasting clinical phenotypes. Here, we have elucidated the functional consequences of a NaV1.9 mutation (L1302F) that is associated with insensitivity to pain. We investigated the effects of L1302F and a previously reported mutation (L811P) on neuronal excitability. In transfected heterologous cells, the L1302F mutation caused a large hyperpolarizing shift in the voltage-dependence of activation, leading to substantially enhanced overlap between activation and steady-state inactivation relationships. In transfected small rat dorsal root ganglion neurons, expression of L1302F and L811P evoked large depolarizations of the resting membrane potential and impaired action potential generation. Therefore, our findings implicate a cellular loss of function as the basis for impaired pain sensation. We further demonstrated that a U-shaped relationship between the resting potential and the neuronal action potential threshold explains why NaV1.9 mutations that evoke small degrees of membrane depolarization cause hyperexcitability and familial episodic pain disorder or painful neuropathy, while mutations evoking larger membrane depolarizations cause hypoexcitability and insensitivity to pain.
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Affiliation(s)
- Jianying Huang
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine; and Rehabilitation Research Center, Veterans Administration Connecticut Healthcare System, West Haven, Connecticut, USA
| | - Carlos G Vanoye
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Alison Cutts
- Xenon Pharmaceuticals, Burnaby, British Columbia, Canada
| | | | - Sulayman D Dib-Hajj
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine; and Rehabilitation Research Center, Veterans Administration Connecticut Healthcare System, West Haven, Connecticut, USA
| | | | - Stephen G Waxman
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine; and Rehabilitation Research Center, Veterans Administration Connecticut Healthcare System, West Haven, Connecticut, USA
| | - Alfred L George
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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37
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Tanaka BS, Nguyen PT, Zhou EY, Yang Y, Yarov-Yarovoy V, Dib-Hajj SD, Waxman SG. Gain-of-function mutation of a voltage-gated sodium channel Na V1.7 associated with peripheral pain and impaired limb development. J Biol Chem 2017; 292:9262-9272. [PMID: 28381558 DOI: 10.1074/jbc.m117.778779] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 03/24/2017] [Indexed: 01/20/2023] Open
Abstract
Dominant mutations in voltage-gated sodium channel NaV1.7 cause inherited erythromelalgia, a debilitating pain disorder characterized by severe burning pain and redness of the distal extremities. NaV1.7 is preferentially expressed within peripheral sensory and sympathetic neurons. Here, we describe a novel NaV1.7 mutation in an 11-year-old male with underdevelopment of the limbs, recurrent attacks of burning pain with erythema, and swelling in his feet and hands. Frequency and duration of the episodes gradually increased with age, and relief by cooling became less effective. The patient's sister had short stature and reported similar complaints of erythema and burning pain, but with less intensity. Genetic analysis revealed a novel missense mutation in NaV1.7 (2567G>C; p.Gly856Arg) in both siblings. The G856R mutation, located within the DII/S4-S5 linker of the channel, substitutes a highly conserved non-polar glycine by a positively charged arginine. Voltage-clamp analysis of G856R currents revealed that the mutation hyperpolarized (-11.2 mV) voltage dependence of activation and slowed deactivation but did not affect fast inactivation, compared with wild-type channels. A mutation of Gly-856 to aspartic acid was previously found in a family with limb pain and limb underdevelopment, and its functional assessment showed hyperpolarized activation, depolarized fast inactivation, and increased ramp current. Structural modeling using the Rosetta computational modeling suite provided structural clues to the divergent effects of the substitution of Gly-856 by arginine and aspartic acid. Although the proexcitatory changes in gating properties of G856R contribute to the pathophysiology of inherited erythromelalgia, the link to limb underdevelopment is not well understood.
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Affiliation(s)
- Brian S Tanaka
- From the Department of Neurology.,the Center for Neuroscience & Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510.,the Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Phuong T Nguyen
- the Department of Physiology and Membrane Biology and.,the Biophysics Graduate Group, University of California, Davis, California 95616
| | - Eray Yihui Zhou
- the Department of Dermatology, Peking University First Hospital, Beijing 100034, China, and.,the Department of Dermatology, Beijing Tsinghua Changgung Hospital, Tsinghua University, Beijing 102218, China
| | - Yong Yang
- the Department of Dermatology, Peking University First Hospital, Beijing 100034, China, and
| | - Vladimir Yarov-Yarovoy
- the Department of Physiology and Membrane Biology and.,the Biophysics Graduate Group, University of California, Davis, California 95616
| | - Sulayman D Dib-Hajj
- From the Department of Neurology.,the Center for Neuroscience & Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510.,the Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Stephen G Waxman
- From the Department of Neurology, .,the Center for Neuroscience & Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510.,the Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
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Vetter I, Deuis JR, Mueller A, Israel MR, Starobova H, Zhang A, Rash LD, Mobli M. NaV1.7 as a pain target – From gene to pharmacology. Pharmacol Ther 2017; 172:73-100. [DOI: 10.1016/j.pharmthera.2016.11.015] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Kapetis D, Sassone J, Yang Y, Galbardi B, Xenakis MN, Westra RL, Szklarczyk R, Lindsey P, Faber CG, Gerrits M, Merkies ISJ, Dib-Hajj SD, Mantegazza M, Waxman SG, Lauria G. Network topology of NaV1.7 mutations in sodium channel-related painful disorders. BMC SYSTEMS BIOLOGY 2017; 11:28. [PMID: 28235406 PMCID: PMC5324268 DOI: 10.1186/s12918-016-0382-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 12/20/2016] [Indexed: 11/30/2022]
Abstract
BACKGROUND Gain-of-function mutations in SCN9A gene that encodes the voltage-gated sodium channel NaV1.7 have been associated with a wide spectrum of painful syndromes in humans including inherited erythromelalgia, paroxysmal extreme pain disorder and small fibre neuropathy. These mutations change the biophysical properties of NaV1.7 channels leading to hyperexcitability of dorsal root ganglion nociceptors and pain symptoms. There is a need for better understanding of how gain-of-function mutations alter the atomic structure of Nav1.7. RESULTS We used homology modeling to build an atomic model of NaV1.7 and a network-based theoretical approach, which can predict interatomic interactions and connectivity arrangements, to investigate how pain-related NaV1.7 mutations may alter specific interatomic bonds and cause connectivity rearrangement, compared to benign variants and polymorphisms. For each amino acid substitution, we calculated the topological parameters betweenness centrality (B ct ), degree (D), clustering coefficient (CC ct ), closeness (C ct ), and eccentricity (E ct ), and calculated their variation (Δ value = mutant value -WT value ). Pathogenic NaV1.7 mutations showed significantly higher variation of |ΔB ct | compared to benign variants and polymorphisms. Using the cut-off value ±0.26 calculated by receiver operating curve analysis, we found that ΔB ct correctly differentiated pathogenic NaV1.7 mutations from variants not causing biophysical abnormalities (nABN) and homologous SNPs (hSNPs) with 76% sensitivity and 83% specificity. CONCLUSIONS Our in-silico analyses predict that pain-related pathogenic NaV1.7 mutations may affect the network topological properties of the protein and suggest |ΔB ct | value as a potential in-silico marker.
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Affiliation(s)
- Dimos Kapetis
- Bioinformatics Unit, IRCCS Foundation “Carlo Besta” Neurological Institute, Milan, Italy
- Neuroalgology Unit, IRCCS Foundation “Carlo Besta” Neurological Institute, Milan, Italy
| | - Jenny Sassone
- Neuroalgology Unit, IRCCS Foundation “Carlo Besta” Neurological Institute, Milan, Italy
- Present address: San Raffaele Scientific Institute and Vita-Salute University, Milan, Italy
| | - Yang Yang
- Department of Neurology, Yale University School of Medicine, New Haven, USA
- Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, USA
| | - Barbara Galbardi
- Bioinformatics Unit, IRCCS Foundation “Carlo Besta” Neurological Institute, Milan, Italy
| | - Markos N. Xenakis
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
- Department of Knowledge Engineering, Maastricht University, Maastricht, The Netherlands
| | - Ronald L. Westra
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
- Department of Knowledge Engineering, Maastricht University, Maastricht, The Netherlands
| | - Radek Szklarczyk
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Patrick Lindsey
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Catharina G. Faber
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
- Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Monique Gerrits
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Ingemar S. J. Merkies
- Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands
- Department of Neurology, Spaarne Hospital, Hoofddorp, The Netherlands
| | - Sulayman D. Dib-Hajj
- Department of Neurology, Yale University School of Medicine, New Haven, USA
- Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, USA
| | - Massimo Mantegazza
- Laboratory of Excellence Ion Channel Science and Therapeutics, Institute of Molecular and Cellular Pharmacology, CNRS UMR7275 & University of Nice-Sophia Antipolis, Valbonne, France
| | - Stephen G. Waxman
- Department of Neurology, Yale University School of Medicine, New Haven, USA
- Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, USA
| | - Giuseppe Lauria
- Neuroalgology Unit, IRCCS Foundation “Carlo Besta” Neurological Institute, Milan, Italy
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Estacion M, Waxman SG. Nonlinear effects of hyperpolarizing shifts in activation of mutant Na v1.7 channels on resting membrane potential. J Neurophysiol 2017; 117:1702-1712. [PMID: 28148645 DOI: 10.1152/jn.00898.2016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 01/11/2017] [Accepted: 01/26/2017] [Indexed: 01/16/2023] Open
Abstract
The Nav1.7 sodium channel is preferentially expressed within dorsal root ganglion (DRG) and sympathetic ganglion neurons. Gain-of-function mutations that cause the painful disorder inherited erythromelalgia (IEM) shift channel activation in a hyperpolarizing direction. When expressed within DRG neurons, these mutations produce a depolarization of resting membrane potential (RMP). The biophysical basis for the depolarized RMP has to date not been established. To explore the effect on RMP of the shift in activation associated with a prototypical IEM mutation (L858H), we used dynamic-clamp models that represent graded shifts that fractionate the effect of the mutation on activation voltage dependence. Dynamic-clamp recording from DRG neurons using a before-and-after protocol for each cell made it possible, even in the presence of cell-to-cell variation in starting RMP, to assess the effects of these graded mutant models. Our results demonstrate a nonlinear, progressively larger effect on RMP as the shift in activation voltage dependence becomes more hyperpolarized. The observed differences in RMP were predicted by the "late" current of each mutant model. Since the depolarization of RMP imposed by IEM mutant channels is known, in itself, to produce hyperexcitability of DRG neurons, the development of pharmacological agents that normalize or partially normalize activation voltage dependence of IEM mutant channels merits further study.NEW & NOTEWORTHY Inherited erythromelalgia (IEM), the first human pain disorder linked to a sodium channel, is widely regarded as a genetic model of neuropathic pain. IEM is produced by Nav1.7 mutations that hyperpolarize activation. These mutations produce a depolarization of resting membrane potential (RMP) in dorsal root ganglion neurons. Using dynamic clamp to explore the effect on RMP of the shift in activation, we demonstrate a nonlinear effect on RMP as the shift in activation voltage dependence becomes more hyperpolarized.
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Affiliation(s)
- Mark Estacion
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and.,Rehabilitation Research Center, Department of Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Stephen G Waxman
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and .,Rehabilitation Research Center, Department of Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
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Michiels JJ. Aspirin responsive erythromelalgia in JAK2-thrombocythemia and incurable inherited erythrothermalgia in neuropathic Nav1.7 sodium channelopathy: from Mitchell 1878 to Michiels 2017. Expert Opin Orphan Drugs 2016. [DOI: 10.1080/21678707.2017.1270822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Jan Jacques Michiels
- Department of Hematology & Coagulation, Academic Hospital Dijkzigt and Erasmus University, Rotterdam, The Netherlands
- Department of Blood and Coagulation Disorders, University Hospital Antwerp, Edegem, Belgium
- Blood, Coagulation and Vascular Medicine Research Center, Goodheart Institute & Foundation in Nature Medicine & Health, Freedom of Science and Education, European Free University, Erasmus Tower, Rotterdam
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42
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[Erythromelalgia: Diagnosis and therapeutic approach]. Rev Med Interne 2016; 38:176-180. [PMID: 27639908 DOI: 10.1016/j.revmed.2016.08.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Accepted: 08/10/2016] [Indexed: 12/29/2022]
Abstract
Erythromelalgia is a rare intermittent vascular acrosyndrome characterized by the combination of recurrent burning pain, warmth and redness of the extremities. It is considered in its primary form as an autosomal dominant neuropathy related to mutations of SCN9A, the encoding gene of a voltage-gated sodium channel subtype Nav1.7. Secondary erythromelalgia is associated with myeloproliferative disorders, drugs (bromocriptine, calcium channel blockers), or clinical conditions such as rheumatic diseases or viral infection. Primary familial erythromelalgia include genetics and sporadic forms associated with small fibers neuropathy. Aspirin is a useful treatment of erythromelagia associated with myeloproliferative disorders. Treatment of primary erythromelalgia is difficult, individualized, with sodium channel blockers such as lidocaine, carbamazepine and mexiletine.
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Kist AM, Sagafos D, Rush AM, Neacsu C, Eberhardt E, Schmidt R, Lunden LK, Ørstavik K, Kaluza L, Meents J, Zhang Z, Carr TH, Salter H, Malinowsky D, Wollberg P, Krupp J, Kleggetveit IP, Schmelz M, Jørum E, Lampert A, Namer B. SCN10A Mutation in a Patient with Erythromelalgia Enhances C-Fiber Activity Dependent Slowing. PLoS One 2016; 11:e0161789. [PMID: 27598514 PMCID: PMC5012686 DOI: 10.1371/journal.pone.0161789] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 08/11/2016] [Indexed: 11/18/2022] Open
Abstract
Gain-of-function mutations in the tetrodotoxin (TTX) sensitive voltage-gated sodium channel (Nav) Nav1.7 have been identified as a key mechanism underlying chronic pain in inherited erythromelalgia. Mutations in TTX resistant channels, such as Nav1.8 or Nav1.9, were recently connected with inherited chronic pain syndromes. Here, we investigated the effects of the p.M650K mutation in Nav1.8 in a 53 year old patient with erythromelalgia by microneurography and patch-clamp techniques. Recordings of the patient’s peripheral nerve fibers showed increased activity dependent slowing (ADS) in CMi and less spontaneous firing compared to a control group of erythromelalgia patients without Nav mutations. To evaluate the impact of the p.M650K mutation on neuronal firing and channel gating, we performed current and voltage-clamp recordings on transfected sensory neurons (DRGs) and neuroblastoma cells. The p.M650K mutation shifted steady-state fast inactivation of Nav1.8 to more hyperpolarized potentials and did not significantly alter any other tested gating behaviors. The AP half-width was significantly broader and the stimulated action potential firing rate was reduced for M650K transfected DRGs compared to WT. We discuss the potential link between enhanced steady state fast inactivation, broader action potential width and the potential physiological consequences.
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Affiliation(s)
- Andreas M. Kist
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Dagrun Sagafos
- Section of Clinical Neurophysiology, Department of Neurology, Oslo University Hospital -Rikshospitalet, Oslo, Norway
| | | | - Cristian Neacsu
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Esther Eberhardt
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Department of Anesthesiology, Friedrich-Alexander-Universität Erlangen-Nuremberg, Erlangen, Germany
| | - Roland Schmidt
- Department of Neuroscience, Clinical Neurophysiology, Uppsala University, Uppsala, Sweden
| | - Lars Kristian Lunden
- Section of Clinical Neurophysiology, Department of Neurology, Oslo University Hospital -Rikshospitalet, Oslo, Norway
| | - Kristin Ørstavik
- Section of Clinical Neurophysiology, Department of Neurology, Oslo University Hospital -Rikshospitalet, Oslo, Norway
| | - Luisa Kaluza
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Jannis Meents
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
| | | | | | | | | | | | | | - Inge Petter Kleggetveit
- Section of Clinical Neurophysiology, Department of Neurology, Oslo University Hospital -Rikshospitalet, Oslo, Norway
| | - Martin Schmelz
- Department of Anesthesiology Mannheim, Heidelberg University, Mannheim, Germany
| | - Ellen Jørum
- Section of Clinical Neurophysiology, Department of Neurology, Oslo University Hospital -Rikshospitalet, Oslo, Norway
- * E-mail: (EJ); (AL); (BN)
| | - Angelika Lampert
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
- * E-mail: (EJ); (AL); (BN)
| | - Barbara Namer
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Department of Anesthesiology Mannheim, Heidelberg University, Mannheim, Germany
- * E-mail: (EJ); (AL); (BN)
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Advanced Genetic Testing Comes to the Pain Clinic to Make a Diagnosis of Paroxysmal Extreme Pain Disorder. Case Rep Neurol Med 2016; 2016:9212369. [PMID: 27525141 PMCID: PMC4972908 DOI: 10.1155/2016/9212369] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 06/02/2016] [Accepted: 06/26/2016] [Indexed: 12/22/2022] Open
Abstract
Objective. To describe the use of an advanced genetic testing technique, whole exome sequencing, to diagnose a patient and their family with a SCN9A channelopathy. Setting. Academic tertiary care center. Design. Case report. Case Report. A 61-year-old female with a history of acute facial pain, chronic pain, fibromyalgia, and constipation was found to have a gain of function SCN9A mutation by whole exome sequencing. This mutation resulted in an SCN9A channelopathy that is most consistent with a diagnosis of paroxysmal extreme pain disorder. In addition to the patient being diagnosed, four siblings have a clinical diagnosis of SCN9A channelopathy as they have consistent symptoms and a sister with a known mutation. For treatment, gabapentin was ineffective and carbamazepine was not tolerated. Nontraditional therapies improved symptoms and constipation resolved with pelvic floor retraining with biofeedback. Conclusion. Patients with a personal and family history of chronic pain may benefit from a referral to Medical Genetics. Pelvic floor retraining with biofeedback should be considered for patients with a SCN9A channelopathy and constipation.
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Ghovanloo MR, Aimar K, Ghadiry-Tavi R, Yu A, Ruben PC. Physiology and Pathophysiology of Sodium Channel Inactivation. CURRENT TOPICS IN MEMBRANES 2016; 78:479-509. [PMID: 27586293 DOI: 10.1016/bs.ctm.2016.04.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Voltage-gated sodium channels are present in different tissues within the human body, predominantly nerve, muscle, and heart. The sodium channel is composed of four similar domains, each containing six transmembrane segments. Each domain can be functionally organized into a voltage-sensing region and a pore region. The sodium channel may exist in resting, activated, fast inactivated, or slow inactivated states. Upon depolarization, when the channel opens, the fast inactivation gate is in its open state. Within the time frame of milliseconds, this gate closes and blocks the channel pore from conducting any more sodium ions. Repetitive or continuous stimulations of sodium channels result in a rate-dependent decrease of sodium current. This process may continue until the channel fully shuts down. This collapse is known as slow inactivation. This chapter reviews what is known to date regarding, sodium channel inactivation with a focus on various mutations within each NaV subtype and with clinical implications.
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Affiliation(s)
- M-R Ghovanloo
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC, Canada
| | - K Aimar
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC, Canada
| | - R Ghadiry-Tavi
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC, Canada
| | - A Yu
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC, Canada
| | - P C Ruben
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC, Canada
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Specific changes in conduction velocity recovery cycles of single nociceptors in a patient with erythromelalgia with the I848T gain-of-function mutation of Nav1.7. Pain 2016; 156:1637-1646. [PMID: 25993546 DOI: 10.1097/j.pain.0000000000000229] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Seven patients diagnosed with erythromelalgia (EM) were investigated by microneurography to record from unmyelinated nerve fibers in the peroneal nerve. Two patients had characterized variants of sodium channel Nav1.7 (I848T, I228M), whereas no mutations of coding regions of Navs were found in 5 patients with EM. Irrespective of Nav1.7 mutations, more than 50% of the silent nociceptors in the patients with EM showed spontaneous activity. In the patient with mutation I848T, all nociceptors, but not sympathetic efferents, displayed enhanced early subnormal conduction in the velocity recovery cycles and the expected late subnormality was reversed to supranormal conduction. The larger hyperpolarizing shift of activation might explain the difference to the I228M mutation. Sympathetic fibers that lack Nav1.8 did not show supranormal conduction in the patient carrying the I848T mutation, confirming in human subjects that the presence of Nav1.8 crucially modulates conduction in cells expressing EM mutant channels. The characteristic pattern of changes in conduction velocity observed in the patient with the I848T gain-of function mutation in Nav1.7 could be explained by axonal depolarization and concomitant inactivation of Nav1.7. If this were true, activity-dependent hyperpolarization would reverse inactivation of Nav1.7 and account for the supranormal CV. This mechanism might explain normal pain thresholds under resting conditions.
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Cao L, McDonnell A, Nitzsche A, Alexandrou A, Saintot PP, Loucif AJ, Brown AR, Young G, Mis M, Randall A, Waxman SG, Stanley P, Kirby S, Tarabar S, Gutteridge A, Butt R, McKernan RM, Whiting P, Ali Z, Bilsland J, Stevens EB. Pharmacological reversal of a pain phenotype in iPSC-derived sensory neurons and patients with inherited erythromelalgia. Sci Transl Med 2016; 8:335ra56. [DOI: 10.1126/scitranslmed.aad7653] [Citation(s) in RCA: 131] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 04/01/2016] [Indexed: 12/25/2022]
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McDonnell A, Schulman B, Ali Z, Dib-Hajj SD, Brock F, Cobain S, Mainka T, Vollert J, Tarabar S, Waxman SG. Inherited erythromelalgia due to mutations inSCN9A:natural history, clinical phenotype and somatosensory profile. Brain 2016; 139:1052-65. [DOI: 10.1093/brain/aww007] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Accepted: 12/04/2015] [Indexed: 12/12/2022] Open
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49
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Tang Z, Chen Z, Tang B, Jiang H. Primary erythromelalgia: a review. Orphanet J Rare Dis 2015; 10:127. [PMID: 26419464 PMCID: PMC4589109 DOI: 10.1186/s13023-015-0347-1] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 09/24/2015] [Indexed: 12/19/2022] Open
Abstract
Primary erythromelalgia (PE ORPHA90026) is a rare autosomal dominant neuropathy characterized by the combination of recurrent burning pain, warmth and redness of the extremities. The incidence rate of PE ranges from 0.36 to 1.1 per 100,000 persons. Gender ratio differs according to different studies and no evidence showed a gender preference. Clinical onset of PE is often in the first decade of life. Burning pain is the most predominant symptom and is usually caused and precipitated by warmth and physical activities. Reported cases of PE contain both inherited and sporadic forms. Genetic etiology of PE is mutations on SCN9A, the encoding gene of a voltage-gated sodium channel subtype Nav1.7. Diagnosis of PE is made upon clinical manifestations and screening for mutations on SCN9A. Exclusion of several other treatable diseases/secondary erythromelalgia is also necessary because of the lack of biomarkers specifically for PE. Differential diagnoses can include Fabry disease, cellulites, Raynaud phenomenon, vasculitis and so on. Diagnostic methods often involve complete blood count, imaging studies and thermograph. Treatment for PE is unsatisfactory and highly individualized. Frequently used pain relieving drugs involve sodium channel blockers such as lidocaine, carbamazepine and mexiletine. Novel drugs such as PF-05089771 and TV-45070 could be promising in ameliorating pain symptoms due to their Nav1.7 selectivity. Patients’ symptoms often worsen over time and many patients develop ulcerations and gangrenes caused by excessive exposure to low temperature in order to relieve pain. This review mainly focuses on PE and the causative gene SCN9A -- its mutations and their effects on Nav1.7 channels’ electrophysiological properties. We propose a genotype-channelopathy-phenotype correlation network underlying PE etiology which could provide guidance for future therapeutics.
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Affiliation(s)
- Zhaoli Tang
- Department of Neurology, Xiangya Hospital, Central South University, 87 Xiangya road, Changsha, 410008, Hunan, China.
| | - Zhao Chen
- Department of Neurology, Xiangya Hospital, Central South University, 87 Xiangya road, Changsha, 410008, Hunan, China.
| | - Beisha Tang
- Department of Neurology, Xiangya Hospital, Central South University, 87 Xiangya road, Changsha, 410008, Hunan, China. .,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, 87 Xiangya road, Changsha, 410008, Hunan, China. .,State Key Lab of Medical Genetics, Central South University, 110 Xiangya road, Changsha, 410078, Hunan, China.
| | - Hong Jiang
- Department of Neurology, Xiangya Hospital, Central South University, 87 Xiangya road, Changsha, 410008, Hunan, China. .,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, 87 Xiangya road, Changsha, 410008, Hunan, China. .,State Key Lab of Medical Genetics, Central South University, 110 Xiangya road, Changsha, 410078, Hunan, China.
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50
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Idiopathic generalized epilepsy and hypokalemic periodic paralysis in a family of South Indian descent. Case Rep Neurol Med 2015; 2015:906049. [PMID: 25893123 PMCID: PMC4393904 DOI: 10.1155/2015/906049] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Revised: 03/01/2015] [Accepted: 03/15/2015] [Indexed: 12/12/2022] Open
Abstract
Inherited channelopathies are a heterogeneous group of disorders resulting from dysfunction of ion channels in cellular membranes. They may manifest as diseases affecting skeletal muscle contraction, the conduction system of the heart, nervous system function, and vision syndromes. We describe a family of South Indian descent with hypokalemic periodic paralysis in which four members also have idiopathic generalized epilepsy. Hypokalemic periodic paralysis is a genetically heterogeneous channelopathy that has been linked to mutations in genes encoding three ion channels CACNIAS, SCN4A, and KCNJ2 predominantly. Although data on specific gene in idiopathic generalized epilepsy is relatively scarce, mutations of voltage gated sodium channel subunit genes (CACNB4) and nonsense mutations in voltage gated calcium channels (CACNA1A) have been linked to idiopathic generalized epilepsy in two families. We speculate that gene mutations altering the ability of the beta subunit to interact with the alpha subunit of the CaV1.1 channel and mutations in the pore-forming potassium channel subunit may be possible explanations for the combined manifestation of both diseases. Functional analysis of voltage gated calcium channel and other ion channels mutations may provide additional support and insight for the causal role of these mutations. The understanding of mutations in ion-channel genes will lead to improved diagnosis and treatment of such inherited channelopathies.
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