1
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Loose S, Lischka A, Kuehs S, Nau C, Heinemann SH, Kurth I, Leipold E. Peripheral temperature dysregulation associated with functionally altered Na V1.8 channels. Pflugers Arch 2023; 475:1343-1355. [PMID: 37695396 PMCID: PMC10567936 DOI: 10.1007/s00424-023-02856-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 08/23/2023] [Accepted: 09/01/2023] [Indexed: 09/12/2023]
Abstract
The voltage-gated sodium channel NaV1.8 is prominently expressed in the soma and axons of small-caliber sensory neurons, and pathogenic variants of the corresponding gene SCN10A are associated with peripheral pain and autonomic dysfunction. While most disease-associated SCN10A variants confer gain-of-function properties to NaV1.8, resulting in hyperexcitability of sensory neurons, a few affect afferent excitability through a loss-of-function mechanism. Using whole-exome sequencing, we here identify a rare heterozygous SCN10A missense variant resulting in alteration p.V1287I in NaV1.8 in a patient with a 15-year history of progressively worsening temperature dysregulation in the distal extremities, particularly in the feet. Further symptoms include increasingly intensifying tingling and numbness in the fingers and increased sweating. To assess the impact of p.V1287I on channel function, we performed voltage-clamp recordings demonstrating that the alteration confers loss- and gain-of-function characteristics to NaV1.8 characterized by a right-shifted voltage dependence of channel activation and inactivation. Current-clamp recordings from transfected mouse dorsal root ganglion neurons further revealed that NaV1.8-V1287I channels broaden the action potentials of sensory neurons and increase their firing rates in response to depolarizing current stimulations, indicating a gain-of-function mechanism of the variant at the cellular level in a heterozygous setting. The data support the hypothesis that the properties of NaV1.8 p.V1287I are causative for the patient's symptoms and that nonpainful peripheral paresthesias should be considered part of the clinical spectrum of NaV1.8-associated disorders.
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Affiliation(s)
- Simon Loose
- Department of Anesthesiology and Intensive Care & CBBM - Center of Brain, Behavior and Metabolism, University of Luebeck, Ratzeburger Allee 160, 23562, Luebeck, Germany
| | - Annette Lischka
- Institute for Human Genetics and Genomic Medicine, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Samuel Kuehs
- Department of Anesthesiology and Intensive Care & CBBM - Center of Brain, Behavior and Metabolism, University of Luebeck, Ratzeburger Allee 160, 23562, Luebeck, Germany
| | - Carla Nau
- Department of Anesthesiology and Intensive Care & CBBM - Center of Brain, Behavior and Metabolism, University of Luebeck, Ratzeburger Allee 160, 23562, Luebeck, Germany
| | - Stefan H Heinemann
- Center for Molecular Biomedicine, Department of Biophysics, Friedrich Schiller University Jena and Jena University Hospital, Jena, Germany
| | - Ingo Kurth
- Institute for Human Genetics and Genomic Medicine, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Enrico Leipold
- Department of Anesthesiology and Intensive Care & CBBM - Center of Brain, Behavior and Metabolism, University of Luebeck, Ratzeburger Allee 160, 23562, Luebeck, Germany.
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2
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Salvage SC, Rahman T, Eagles DA, Rees JS, King GF, Huang CL, Jackson AP. The β3-subunit modulates the effect of venom peptides ProTx-II and OD1 on Na V 1.7 gating. J Cell Physiol 2023; 238:1354-1367. [PMID: 37042220 PMCID: PMC10953403 DOI: 10.1002/jcp.31018] [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: 04/12/2022] [Revised: 03/13/2023] [Accepted: 03/15/2023] [Indexed: 04/13/2023]
Abstract
The voltage-gated sodium channel NaV 1.7 is involved in various pain phenotypes and is physiologically regulated by the NaV -β3-subunit. Venom toxins ProTx-II and OD1 modulate NaV 1.7 channel function and may be useful as therapeutic agents and/or research tools. Here, we use patch-clamp recordings to investigate how the β3-subunit can influence and modulate the toxin-mediated effects on NaV 1.7 function, and we propose a putative binding mode of OD1 on NaV 1.7 to rationalise its activating effects. The inhibitor ProTx-II slowed the rate of NaV 1.7 activation, whilst the activator OD1 reduced the rate of fast inactivation and accelerated recovery from inactivation. The β3-subunit partially abrogated these effects. OD1 induced a hyperpolarising shift in the V1/2 of steady-state activation, which was not observed in the presence of β3. Consequently, OD1-treated NaV 1.7 exhibited an enhanced window current compared with OD1-treated NaV 1.7-β3 complex. We identify candidate OD1 residues that are likely to prevent the upward movement of the DIV S4 helix and thus impede fast inactivation. The binding sites for each of the toxins and the predicted location of the β3-subunit on the NaV 1.7 channel are distinct. Therefore, we infer that the β3-subunit influences the interaction of toxins with NaV 1.7 via indirect allosteric mechanisms. The enhanced window current shown by OD1-treated NaV 1.7 compared with OD1-treated NaV 1.7-β3 is discussed in the context of differing cellular expressions of NaV 1.7 and the β3-subunit in dorsal root ganglion (DRG) neurons. We propose that β3, as the native binding partner for NaV 1.7 in DRG neurons, should be included during screening of molecules against NaV 1.7 in relevant analgesic discovery campaigns.
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Affiliation(s)
| | - Taufiq Rahman
- Department of PharmacologyUniversity of CambridgeCambridgeUK
| | - David A. Eagles
- Institute of Molecular BioscienceUniversity of QueenslandBrisbaneQLDAustralia
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein ScienceThe University of QueenslandBrisbaneQLDAustralia
| | - Johanna S. Rees
- Department of BiochemistryUniversity of CambridgeCambridgeUK
- Present address:
Babraham Research CampusPetMedix Ltd.CambridgeUK
| | - Glenn F. King
- Institute of Molecular BioscienceUniversity of QueenslandBrisbaneQLDAustralia
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein ScienceThe University of QueenslandBrisbaneQLDAustralia
| | - Christopher L‐H. Huang
- Department of BiochemistryUniversity of CambridgeCambridgeUK
- Department of Physiology, Development and NeuroscienceUniversity of CambridgeCambridgeUK
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3
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Almomani R, Sopacua M, Marchi M, Ślęczkowska M, Lindsey P, de Greef BTA, Hoeijmakers JGJ, Salvi E, Merkies ISJ, Ferdousi M, Malik RA, Ziegler D, Derks KWJ, Boenhof G, Martinelli-Boneschi F, Cazzato D, Lombardi R, Dib-Hajj S, Waxman SG, Smeets HJM, Gerrits MM, Faber CG, Lauria G. Genetic Profiling of Sodium Channels in Diabetic Painful and Painless and Idiopathic Painful and Painless Neuropathies. Int J Mol Sci 2023; 24:ijms24098278. [PMID: 37175987 PMCID: PMC10179245 DOI: 10.3390/ijms24098278] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 04/15/2023] [Accepted: 04/28/2023] [Indexed: 05/15/2023] Open
Abstract
Neuropathic pain is a frequent feature of diabetic peripheral neuropathy (DPN) and small fiber neuropathy (SFN). Resolving the genetic architecture of these painful neuropathies will lead to better disease management strategies, counselling and intervention. Our aims were to profile ten sodium channel genes (SCG) expressed in a nociceptive pathway in painful and painless DPN and painful and painless SFN patients, and to provide a perspective for clinicians who assess patients with painful peripheral neuropathy. Between June 2014 and September 2016, 1125 patients with painful-DPN (n = 237), painless-DPN (n = 309), painful-SFN (n = 547) and painless-SFN (n = 32), recruited in four different centers, were analyzed for SCN3A, SCN7A-SCN11A and SCN1B-SCN4B variants by single molecule Molecular inversion probes-Next Generation Sequence. Patients were grouped based on phenotype and the presence of SCG variants. Screening of SCN3A, SCN7A-SCN11A, and SCN1B-SCN4B revealed 125 different (potential) pathogenic variants in 194 patients (17.2%, n = 194/1125). A potential pathogenic variant was present in 18.1% (n = 142/784) of painful neuropathy patients vs. 15.2% (n = 52/341) of painless neuropathy patients (17.3% (n = 41/237) for painful-DPN patients, 14.9% (n = 46/309) for painless-DPN patients, 18.5% (n = 101/547) for painful-SFN patients, and 18.8% (n = 6/32) for painless-SFN patients). Of the variants detected, 70% were in SCN7A, SCN9A, SCN10A and SCN11A. The frequency of SCN9A and SCN11A variants was the highest in painful-SFN patients, SCN7A variants in painful-DPN patients, and SCN10A variants in painless-DPN patients. Our findings suggest that rare SCG genetic variants may contribute to the development of painful neuropathy. Genetic profiling and SCG variant identification should aid in a better understanding of the genetic variability in patients with painful and painless neuropathy, and may lead to better risk stratification and the development of more targeted and personalized pain treatments.
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Affiliation(s)
- Rowida Almomani
- Department of Medical Laboratory Sciences, Jordan University of Science and Technology, Irbid 22110, Jordan
- Clinical Genomics Unit, Department of Genetics and Cell Biology, Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Maurice Sopacua
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Centre+, 6229 HX Maastricht, The Netherlands
| | - Margherita Marchi
- Neuroalgology Unit, IRCCS Foundation "Carlo Besta" Neurological Institute, 20133 Milan, Italy
| | - Milena Ślęczkowska
- Clinical Genomics Unit, Department of Genetics and Cell Biology, Maastricht University, 6229 ER Maastricht, The Netherlands
- Department of Toxicogenomics, Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Patrick Lindsey
- Clinical Genomics Unit, Department of Genetics and Cell Biology, Maastricht University, 6229 ER Maastricht, The Netherlands
- Department of Toxicogenomics, Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Bianca T A de Greef
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Centre+, 6229 HX Maastricht, The Netherlands
| | - Janneke G J Hoeijmakers
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Centre+, 6229 HX Maastricht, The Netherlands
| | - Erika Salvi
- Neuroalgology Unit, IRCCS Foundation "Carlo Besta" Neurological Institute, 20133 Milan, Italy
| | - Ingemar S J Merkies
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Centre+, 6229 HX Maastricht, The Netherlands
- Department of Neurology, Curaçao Medical Center, 4365+37Q, J. H. J. Hamelbergweg, Willemstad, Curacao
| | - Maryam Ferdousi
- Institute of Cardiovascular Sciences, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester M13 9P, UK
| | - Rayaz A Malik
- Institute of Cardiovascular Sciences, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester M13 9P, UK
- Weill Cornell Medicine-Qatar, Doha P.O. Box 24144, Qatar
| | - Dan Ziegler
- German Diabetes Centre, 40225 Düsseldorf, Germany
| | - Kasper W J Derks
- Department of Clinical Genetics, Maastricht University Medical Centre+, 6229 HX Maastricht, The Netherlands
| | - Gidon Boenhof
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, 40225 Düsseldorf, Germany
| | - Filippo Martinelli-Boneschi
- Laboratory of Human Genetics of Neurological Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, 20132 Milan, Italy
| | - Daniele Cazzato
- Neuroalgology Unit, IRCCS Foundation "Carlo Besta" Neurological Institute, 20133 Milan, Italy
| | - Raffaella Lombardi
- Neuroalgology Unit, IRCCS Foundation "Carlo Besta" Neurological Institute, 20133 Milan, Italy
| | - Sulayman Dib-Hajj
- Department of Neurology, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Stephen G Waxman
- Department of Neurology, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Hubert J M Smeets
- Clinical Genomics Unit, Department of Genetics and Cell Biology, Maastricht University, 6229 ER Maastricht, The Netherlands
- Department of Toxicogenomics, Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Monique M Gerrits
- Department of Clinical Genetics, Maastricht University Medical Centre+, 6229 HX Maastricht, The Netherlands
| | - Catharina G Faber
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Centre+, 6229 HX Maastricht, The Netherlands
| | - Giuseppe Lauria
- Neuroalgology Unit, IRCCS Foundation "Carlo Besta" Neurological Institute, 20133 Milan, Italy
- Department of Biomedical and Clinical Sciences "Luigi Sacco", University of Milan, 20157 Milan, Italy
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4
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Mamatsi E, Giorgi M, Dinopoulos A, Papaevangelou V, Fotis L. Erythromelalgia in an Adolescent Female. Mediterr J Rheumatol 2022; 33:256-258. [PMID: 36128208 PMCID: PMC9450199 DOI: 10.31138/mjr.33.2.256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 09/07/2021] [Accepted: 09/20/2021] [Indexed: 11/04/2022] Open
Abstract
Erythromelalgia is a disabling syndrome of paroxysmal vasodilation affecting the feet, hands and face characterised by patient's cooling behaviour to achieve symptom relief. It can be primary or secondary and although a rare disorder it has been described in children and adolescents. We describe the case of a 14-year-old female diagnosed with primary erythromelalgia successfully treated with aspirin, amitriptyline, and carbamazepine.
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Affiliation(s)
- Eleftheria Mamatsi
- Department of Pediatrics, Attikon General Hospital, National and Kapodistrian University of Athens, Greece
| | - Melpomeni Giorgi
- Department of Pediatrics, Attikon General Hospital, National and Kapodistrian University of Athens, Greece
| | - Argirios Dinopoulos
- Department of Pediatrics, Attikon General Hospital, National and Kapodistrian University of Athens, Greece
| | - Vasiliki Papaevangelou
- Department of Pediatrics, Attikon General Hospital, National and Kapodistrian University of Athens, Greece
| | - Lampros Fotis
- Department of Pediatrics, Attikon General Hospital, National and Kapodistrian University of Athens, Greece
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5
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Sepela RJ, Stewart RG, Valencia LA, Thapa P, Wang Z, Cohen BE, Sack JT. The AMIGO1 adhesion protein activates Kv2.1 voltage sensors. Biophys J 2022; 121:1395-1416. [PMID: 35314141 PMCID: PMC9072587 DOI: 10.1016/j.bpj.2022.03.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 11/11/2021] [Accepted: 03/16/2022] [Indexed: 11/30/2022] Open
Abstract
Kv2 voltage-gated potassium channels are modulated by amphoterin-induced gene and open reading frame (AMIGO) neuronal adhesion proteins. Here, we identify steps in the conductance activation pathway of Kv2.1 channels that are modulated by AMIGO1 using voltage-clamp recordings and spectroscopy of heterologously expressed Kv2.1 and AMIGO1 in mammalian cell lines. AMIGO1 speeds early voltage-sensor movements and shifts the gating charge-voltage relationship to more negative voltages. The gating charge-voltage relationship indicates that AMIGO1 exerts a larger energetic effect on voltage-sensor movement than is apparent from the midpoint of the conductance-voltage relationship. When voltage sensors are detained at rest by voltage-sensor toxins, AMIGO1 has a greater impact on the conductance-voltage relationship. Fluorescence measurements from voltage-sensor toxins bound to Kv2.1 indicate that with AMIGO1, the voltage sensors enter their earliest resting conformation, yet this conformation is less stable upon voltage stimulation. We conclude that AMIGO1 modulates the Kv2.1 conductance activation pathway by destabilizing the earliest resting state of the voltage sensors.
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Affiliation(s)
- Rebecka J Sepela
- Department of Physiology and Membrane Biology, University of California, Davis, California
| | - Robert G Stewart
- Department of Physiology and Membrane Biology, University of California, Davis, California
| | - Luis A Valencia
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California
| | - Parashar Thapa
- Department of Physiology and Membrane Biology, University of California, Davis, California
| | - Zeming Wang
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California
| | - Bruce E Cohen
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California; Division of Molecular Biophysics & Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, California
| | - Jon T Sack
- Department of Physiology and Membrane Biology, University of California, Davis, California; Department of Anesthesiology and Pain Medicine, University of California, Davis, California.
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6
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Labau JIR, Alsaloum M, Estacion M, Tanaka B, Dib-Hajj FB, Lauria G, Smeets HJM, Faber CG, Dib-Hajj S, Waxman SG. Lacosamide Inhibition of Na V1.7 Channels Depends on its Interaction With the Voltage Sensor Domain and the Channel Pore. Front Pharmacol 2022; 12:791740. [PMID: 34992539 PMCID: PMC8724789 DOI: 10.3389/fphar.2021.791740] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 12/02/2021] [Indexed: 12/14/2022] Open
Abstract
Lacosamide, developed as an anti-epileptic drug, has been used for the treatment of pain. Unlike typical anticonvulsants and local anesthetics which enhance fast-inactivation and bind within the pore of sodium channels, lacosamide enhances slow-inactivation of these channels, suggesting different binding mechanisms and mode of action. It has been reported that lacosamide's effect on NaV1.5 is sensitive to a mutation in the local anesthetic binding site, and that it binds with slow kinetics to the fast-inactivated state of NaV1.7. We recently showed that the NaV1.7-W1538R mutation in the voltage-sensing domain 4 completely abolishes NaV1.7 inhibition by clinically-achievable concentration of lacosamide. Our molecular docking analysis suggests a role for W1538 and pore residues as high affinity binding sites for lacosamide. Aryl sulfonamide sodium channel blockers are also sensitive to substitutions of the W1538 residue but not of pore residues. To elucidate the mechanism by which lacosamide exerts its effects, we used voltage-clamp recordings and show that lacosamide requires an intact local anesthetic binding site to inhibit NaV1.7 channels. Additionally, the W1538R mutation does not abrogate local anesthetic lidocaine-induced blockade. We also show that the naturally occurring arginine in NaV1.3 (NaV1.3-R1560), which corresponds to NaV1.7-W1538R, is not sufficient to explain the resistance of NaV1.3 to clinically-relevant concentrations of lacosamide. However, the NaV1.7-W1538R mutation conferred sensitivity to the NaV1.3-selective aryl-sulfonamide blocker ICA-121431. Together, the W1538 residue and an intact local anesthetic site are required for lacosamide's block of NaV1.7 at a clinically-achievable concentration. Moreover, the contribution of W1538 to lacosamide inhibitory effects appears to be isoform-specific.
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Affiliation(s)
- Julie I R Labau
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT, United States.,Rehabilitation Research Center, Veteran Affairs Connecticut Healthcare System, West Haven, CT, United States.,Department of Toxicogenomics, Clinical Genomics, Maastricht University Medical Centre+, Maastricht, Netherlands.,School of Mental Health and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Matthew Alsaloum
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT, United States.,Rehabilitation Research Center, Veteran Affairs Connecticut Healthcare System, West Haven, CT, United States.,Yale Medical Scientist Training Program, Yale School of Medicine, New Haven, CT, United States.,Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT, United States
| | - Mark Estacion
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT, United States.,Rehabilitation Research Center, Veteran Affairs Connecticut Healthcare System, West Haven, CT, United States
| | - Brian Tanaka
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT, United States.,Rehabilitation Research Center, Veteran Affairs Connecticut Healthcare System, West Haven, CT, United States
| | - Fadia B Dib-Hajj
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT, United States.,Rehabilitation Research Center, Veteran Affairs Connecticut Healthcare System, West Haven, CT, United States
| | - Giuseppe Lauria
- Neuroalgology Unit, IRCCS Foundation, "Carlo Besta" Neurological Institute, Milan, Italy.,Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Hubert J M Smeets
- Department of Toxicogenomics, Clinical Genomics, Maastricht University Medical Centre+, Maastricht, Netherlands.,School of Mental Health and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Catharina G Faber
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, Netherlands
| | - Sulayman Dib-Hajj
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT, United States.,Rehabilitation Research Center, Veteran Affairs Connecticut Healthcare System, West Haven, CT, United States
| | - Stephen G Waxman
- Department of Neurology, Yale University School of Medicine, New Haven, CT, United States.,Center for Neuroscience and Regeneration Research, Yale University, West Haven, CT, United States.,Rehabilitation Research Center, Veteran Affairs Connecticut Healthcare System, West Haven, CT, United States
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7
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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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8
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Small-fibre pathology has no impact on somatosensory system function in patients with fibromyalgia. Pain 2021; 161:2385-2393. [PMID: 32897040 DOI: 10.1097/j.pain.0000000000001920] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We aimed to investigate whether small-fibre pathology, a common skin biopsy finding in patients with fibromyalgia, implies clinically important abnormalities of somatosensory system function and verify whether it is associated with voltage-gated sodium channel variants. In 57 consecutively enrolled patients with fibromyalgia, we used skin biopsy to distinguish patients with and without small-fibre pathology. In all patients, we assessed somatosensory system function using quantitative sensory testing (QST) and laser-evoked potentials and investigated voltage-gated sodium channel genotyping. We then compared these variables in patients with and without small-fibre pathology. We found that clinical measures, QST, and laser-evoked potential variables did not differ between patients with and without small-fibre pathology. In most patients with small-fibre pathology, QST and laser-evoked potential variables fell within normative ranges commonly used in clinical practice. Of the 57 patients, one patient without small-fibre pathology and 2 patients with small-fibre pathology had rare variants of voltage-gated sodium channels, namely SCN11A, SCN9A, and SCN1A variants. The SCN9A variant, found in a patient with small-fibre pathology, was an already profiled gain-of-function mutation, previously reported in small-fibre neuropathy. Our findings suggest that small-fibre pathology has a negligible impact on somatosensory system function in fibromyalgia. The genetic analysis suggests that patients with rare small-fibre neuropathy due to voltage-gated sodium channel variants may be misdiagnosed as patients with fibromyalgia.
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9
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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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10
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Progesterone Attenuates Allodynia of Inflamed Temporomandibular Joint through Modulating Voltage-Gated Sodium Channel 1.7 in Trigeminal Ganglion. Pain Res Manag 2020; 2020:6582586. [PMID: 32774568 PMCID: PMC7399782 DOI: 10.1155/2020/6582586] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 04/27/2020] [Accepted: 06/03/2020] [Indexed: 01/31/2023]
Abstract
Background Women with temporomandibular disorders (TMDs) experience some amelioration of pain during pregnancy. Progesterone increases dramatically and steadily during pregnancy. Sodium channel 1.7 (Nav1.7) plays a prominent role in pain perceptions, as evidenced by deletion of Nav1.7 alone leading to a complete loss of pain. In a previous study, we showed that Nav1.7 in trigeminal ganglion (TG) is involved in allodynia of inflamed temporomandibular joint (TMJ). Whether progesterone modulates allodynia of inflamed TMJ through Nav1.7 in TG remains to be investigated. Methods The effects of progesterone on sodium currents of freshly isolated TG neurons were examined using whole-cell recording. Female rats were ovariectomized and treated with increasing doses of progesterone for 10 days. Complete Freund's adjuvant was administered intra-articularly to induce TMJ inflammation. TMJ nociceptive responses were evaluated by head withdrawal thresholds. Real-time PCR and Western blotting were used to examine Nav1.7 mRNA and protein expression in TG. Immunohistofluorescence was used to examine the colocalization of progesterone receptors (PRα/β) and Nav1.7 in TG. Results Whole-cell recording showed that progesterone could attenuate sodium currents. Moreover, progesterone dose-dependently downregulated Nav1.7 mRNA expression and reduced the sensitivity of TMJ nociception in ovariectomized rats. Furthermore, treatment with progesterone attenuated allodynia of inflamed TMJ in a dose-dependent manner and repressed inflammation-induced Nav1.7 mRNA and protein expression in ovariectomized rats. The progesterone receptor antagonist, RU-486, partially reversed the effect of progesterone on allodynia of inflamed TMJ and TMJ inflammation-induced Nav1.7 mRNA and protein expression. Conclusion Progesterone, by modulating trigeminal ganglionic Nav1.7, may represent a promising agent to prevent allodynia of inflamed TMJ.
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11
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Devigili G, Cazzato D, Lauria G. Clinical diagnosis and management of small fiber neuropathy: an update on best practice. Expert Rev Neurother 2020; 20:967-980. [PMID: 32654574 DOI: 10.1080/14737175.2020.1794825] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Small fiber neuropathy (SFN) is a heterogeneous group of disorders affecting thin myelinated Aδ and unmyelinated C fibers. Common symptoms include neuropathic pain and autonomic disturbances, and the typical clinical presentation is that of a length-dependent polyneuropathy, although other distributions could be present. AREA COVERED This review focuses on several aspects of SFN including etiology, clinical presentation, diagnostic criteria and tests, management, and future perspectives. Diagnostic challenges are discussed, encompassing the role of accurate and standardized assessment of symptoms and signs and providing clues for the clinical practice. The authors discuss the evidence in support of skin biopsy and quantitative sensory testing as diagnostic tests and present an overview of other diagnostic techniques to assess sensory and autonomic fibers dysfunction. The authors also suggest a systematic approach to the etiology including a set of laboratory tests and genetic examinations of sodium channelopathies and other rare conditions that might drive the therapeutic approach based on underlying cause or symptoms treatment. EXPERT OPINION SFN provides a useful model for neuropathic pain whose known mechanisms and cause could pave the way toward personalized treatments.
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Affiliation(s)
- Grazia Devigili
- Movement Disorders Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta" , Milan, Italy
| | - Daniele Cazzato
- Neurophysiology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta" , Milan, Italy
| | - 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
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12
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Labau JIR, Estacion M, Tanaka BS, de Greef BTA, Hoeijmakers JGJ, Geerts M, Gerrits MM, Smeets HJM, Faber CG, Merkies ISJ, Lauria G, Dib-Hajj SD, Waxman SG. Differential effect of lacosamide on Nav1.7 variants from responsive and non-responsive patients with small fibre neuropathy. Brain 2020; 143:771-782. [PMID: 32011655 PMCID: PMC7089662 DOI: 10.1093/brain/awaa016] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 11/13/2019] [Accepted: 12/06/2019] [Indexed: 12/20/2022] Open
Abstract
Small fibre neuropathy is a common pain disorder, which in many cases fails to respond to treatment with existing medications. Gain-of-function mutations of voltage-gated sodium channel Nav1.7 underlie dorsal root ganglion neuronal hyperexcitability and pain in a subset of patients with small fibre neuropathy. Recent clinical studies have demonstrated that lacosamide, which blocks sodium channels in a use-dependent manner, attenuates pain in some patients with Nav1.7 mutations; however, only a subgroup of these patients responded to the drug. Here, we used voltage-clamp recordings to evaluate the effects of lacosamide on five Nav1.7 variants from patients who were responsive or non-responsive to treatment. We show that, at the clinically achievable concentration of 30 μM, lacosamide acts as a potent sodium channel inhibitor of Nav1.7 variants carried by responsive patients, via a hyperpolarizing shift of voltage-dependence of both fast and slow inactivation and enhancement of use-dependent inhibition. By contrast, the effects of lacosamide on slow inactivation and use-dependence in Nav1.7 variants from non-responsive patients were less robust. Importantly, we found that lacosamide selectively enhances fast inactivation only in variants from responders. Taken together, these findings begin to unravel biophysical underpinnings that contribute to responsiveness to lacosamide in patients with small fibre neuropathy carrying select Nav1.7 variants.
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Affiliation(s)
- Julie I R Labau
- Department of Neurology, Yale University School of Medicine, New Haven, CT 06510, USA.,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.,Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands.,Department of Genetics and Cell Biology, Clinical Genomics Unit, Maastricht University, Maastricht, The Netherlands
| | - Mark Estacion
- Department of Neurology, Yale University School of Medicine, New Haven, CT 06510, USA.,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
| | - Brian S Tanaka
- Department of Neurology, Yale University School of Medicine, New Haven, CT 06510, USA.,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
| | - Bianca T A de Greef
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands.,Department of Clinical Epidemiology and Medical Technology Assessment (KEMTA), Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Janneke G J Hoeijmakers
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Margot Geerts
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Monique M Gerrits
- Department of Clinical Genetics, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Hubert J M Smeets
- Department of Genetics and Cell Biology, Clinical Genomics Unit, Maastricht University, Maastricht, The Netherlands
| | - Catharina G Faber
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Ingemar S J Merkies
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands.,Department of Neurology, St. Elisabeth Hospital, Willemstad, Curaçao
| | - Giuseppe Lauria
- Neuroalgology Unit, IRCCS Foundation, "Carlo Besta" Neurological Institute, Milan, Italy.,Department of Biomedical and Clinical Sciences "Luigi Sacco", University of Milan, Italy
| | - Sulayman D Dib-Hajj
- Department of Neurology, Yale University School of Medicine, New Haven, CT 06510, USA.,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
| | - Stephen G Waxman
- Department of Neurology, Yale University School of Medicine, New Haven, CT 06510, USA.,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
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13
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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: 7] [Impact Index Per Article: 1.8] [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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14
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Abstract
Itch is a topic to which everyone can relate. The physiological roles of itch are increasingly understood and appreciated. The pathophysiological consequences of itch impact quality of life as much as pain. These dynamics have led to increasingly deep dives into the mechanisms that underlie and contribute to the sensation of itch. When the prior review on the physiology of itching was published in this journal in 1941, itch was a black box of interest to a small number of neuroscientists and dermatologists. Itch is now appreciated as a complex and colorful Rubik's cube. Acute and chronic itch are being carefully scratched apart and reassembled by puzzle solvers across the biomedical spectrum. New mediators are being identified. Mechanisms blur boundaries of the circuitry that blend neuroscience and immunology. Measures involve psychophysics and behavioral psychology. The efforts associated with these approaches are positively impacting the care of itchy patients. There is now the potential to markedly alleviate chronic itch, a condition that does not end life, but often ruins it. We review the itch field and provide a current understanding of the pathophysiology of itch. Itch is a disease, not only a symptom of disease.
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Affiliation(s)
- Ferda Cevikbas
- Dermira, Inc., Menlo Park, California; and Harvard Medical School and the Cutaneous Biology Research Center at Massachusetts General Hospital, Charlestown, Massachusetts
| | - Ethan A Lerner
- Dermira, Inc., Menlo Park, California; and Harvard Medical School and the Cutaneous Biology Research Center at Massachusetts General Hospital, Charlestown, Massachusetts
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15
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Li ZM, Chen LX, Li H. Voltage-gated Sodium Channels and Blockers: An Overview and Where Will They Go? Curr Med Sci 2019; 39:863-873. [PMID: 31845216 DOI: 10.1007/s11596-019-2117-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 09/02/2019] [Indexed: 11/27/2022]
Abstract
Voltage-gated sodium (Nav) channels are critical players in the generation and propagation of action potentials by triggering membrane depolarization. Mutations in Nav channels are associated with a variety of channelopathies, which makes them relevant targets for pharmaceutical intervention. So far, the cryoelectron microscopic structure of the human Nav1.2, Nav1.4, and Nav1.7 has been reported, which sheds light on the molecular basis of functional mechanism of Nav channels and provides a path toward structure-based drug discovery. In this review, we focus on the recent advances in the structure, molecular mechanism and modulation of Nav channels, and state updated sodium channel blockers for the treatment of pathophysiology disorders and briefly discuss where the blockers may be developed in the future.
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Affiliation(s)
- Zhi-Mei Li
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Li-Xia Chen
- Wuya College of Innovation, Key Laboratory of Structure-Based Drug Design & Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang, 110016, China.
| | - Hua Li
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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16
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Beck VC, Hull JM, Isom LL. Beyond Dravet Syndrome: Characterization of a Novel, More Severe SCN1A-Linked Epileptic Encephalopathy. Epilepsy Curr 2019; 19:266-268. [PMID: 31257984 PMCID: PMC6891832 DOI: 10.1177/1535759719858339] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
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17
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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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18
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Abstract
Diabetic peripheral neuropathy (DPN) is a common disabling complication of diabetes. Almost half of the patients with DPN develop neuropathic pain (NeuP) for which current analgesic treatments are inadequate. Understanding the role of genetic variability in the development of painful DPN is needed for improved understanding of pain pathogenesis for better patient stratification in clinical trials and to target therapy more appropriately. Here, we examined the relationship between variants in the voltage-gated sodium channel NaV1.7 and NeuP in a deeply phenotyped cohort of patients with DPN. Although no rare variants were found in 78 participants with painless DPN, we identified 12 rare NaV1.7 variants in 10 (out of 111) study participants with painful DPN. Five of these variants had previously been described in the context of other NeuP disorders and 7 have not previously been linked to NeuP. Those patients with rare variants reported more severe pain and greater sensitivity to pressure stimuli on quantitative sensory testing. Electrophysiological characterization of 2 of the novel variants (M1852T and T1596I) demonstrated that gain of function changes as a consequence of markedly impaired channel fast inactivation. Using a structural model of NaV1.7, we were also able to provide further insight into the structural mechanisms underlying fast inactivation and the role of the C-terminal domain in this process. Our observations suggest that rare NaV1.7 variants contribute to the development NeuP in patients with DPN. Their identification should aid understanding of sensory phenotype, patient stratification, and help target treatments effectively.
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19
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Eijkenboom I, Sopacua M, Hoeijmakers JGJ, de Greef BTA, Lindsey P, Almomani R, Marchi M, Vanoevelen J, Smeets HJM, Waxman SG, Lauria G, Merkies ISJ, Faber CG, Gerrits MM. Yield of peripheral sodium channels gene screening in pure small fibre neuropathy. J Neurol Neurosurg Psychiatry 2019; 90:342-352. [PMID: 30554136 DOI: 10.1136/jnnp-2018-319042] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 11/01/2018] [Accepted: 11/18/2018] [Indexed: 12/19/2022]
Abstract
BACKGROUND Neuropathic pain is common in peripheral neuropathy. Recent genetic studies have linked pathogenic voltage-gated sodium channel (VGSC) variants to human pain disorders. Our aims are to determine the frequency of SCN9A, SCN10A and SCN11A variants in patients with pure small fibre neuropathy (SFN), analyse their clinical features and provide a rationale for genetic screening. METHODS Between September 2009 and January 2017, 1139 patients diagnosed with pure SFN at our reference centre were screened for SCN9A, SCN10A and SCN11A variants. Pathogenicity of variants was classified according to established guidelines of the Association for Clinical Genetic Science and frequencies were determined. Patients with SFN were grouped according to the VGSC variants detected, and clinical features were compared. RESULTS Among 1139 patients with SFN, 132 (11.6%) patients harboured 73 different (potentially) pathogenic VGSC variants, of which 50 were novel and 22 were found in ≥ 1 patient. The frequency of (potentially) pathogenic variants was 5.1% (n=58/1139) for SCN9A, 3.7% (n=42/1139) for SCN10A and 2.9% (n=33/1139) for SCN11A. Only erythromelalgia-like symptoms and warmth-induced pain were significantly more common in patients harbouring VGSC variants. CONCLUSION (Potentially) pathogenic VGSC variants are present in 11.6% of patients with pure SFN. Therefore, genetic screening of SCN9A, SCN10A and SCN11A should be considered in patients with pure SFN, independently of clinical features or underlying conditions.
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Affiliation(s)
- Ivo Eijkenboom
- Department of Genetics and Cell Biology, Clinical Genomics Unit, Maastricht University, Maastricht, The Netherlands.,MHeNs School of Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Maurice Sopacua
- MHeNs School of Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.,Department of Neurology, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Janneke G J Hoeijmakers
- MHeNs School of Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.,Department of Neurology, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Bianca T A de Greef
- MHeNs School of Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.,Department of Neurology, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Patrick Lindsey
- Department of Genetics and Cell Biology, Clinical Genomics Unit, Maastricht University, Maastricht, The Netherlands
| | - Rowida Almomani
- Department of Genetics and Cell Biology, Clinical Genomics Unit, Maastricht University, Maastricht, The Netherlands.,MHeNs School of Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.,Department of Medical Laboratory Sciences, Jordan University of Science and Technology, Irbid, Jordan
| | - Margherita Marchi
- Neuroalgology Unit, IRCCS Fondazione Istituto Neurologico "Carlo Besta", Milan, Italy
| | - Jo Vanoevelen
- Department of Genetics and Cell Biology, Clinical Genomics Unit, Maastricht University, Maastricht, The Netherlands
| | - Hubertus J M Smeets
- Department of Genetics and Cell Biology, Clinical Genomics Unit, Maastricht University, Maastricht, The Netherlands.,MHeNs School of Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Stephen G Waxman
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut, USA.,Centre for Neuroscience and Regeneration Research, Veterans Affairs Medical Center, West Haven, Connecticut, USA
| | - Giuseppe Lauria
- Neuroalgology Unit, IRCCS Fondazione Istituto Neurologico "Carlo Besta", Milan, Italy.,Department of Biomedical and Clinical Sciences "Luigi Sacco", University of Milan, Milan, Italy
| | - Ingemar S J Merkies
- MHeNs School of Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.,Department of Neurology, St. Elisabeth Hospital, Willemstad, Curaçao
| | - Catharina G Faber
- MHeNs School of Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.,Department of Neurology, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Monique M Gerrits
- Department of Clinical Genetics, Maastricht University Medical Centre, Maastricht, The Netherlands
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20
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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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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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MicroRNA-182 Alleviates Neuropathic Pain by Regulating Nav1.7 Following Spared Nerve Injury in Rats. Sci Rep 2018; 8:16750. [PMID: 30425258 PMCID: PMC6233159 DOI: 10.1038/s41598-018-34755-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 10/24/2018] [Indexed: 02/08/2023] Open
Abstract
The sodium channel 1.7 (Nav1.7), which is encoded by SCN9A gene, is involved in neuropathic pain. As crucial regulators of gene expression, many miRNAs have already gained importance in neuropathic pain, including miR-182, which is predicted to regulate the SCN9A gene. Nav1.7 expression in L4-L6 dorsal root ganglions (DRGs) can be up regulated by spared nerve injury (SNI), while miR-182 expression was down regulated following SNI model. Exploring the connection between Nav1.7 and miR-182 may facilitate the development of a better-targeted therapy. In the current study, direct pairing of miR-182 with the SCN9A gene was verified using a luciferase assay in vitro. Over-expression of miR-182 via microinjection of miR-182 agomir reversed the abnormal increase of Nav1.7 at both mRNA and protein level in L4-6 DRGs of SNI rats, and significantly attenuated the hypersensitivity to mechanical stimulus in the rats. In contrast, administration of miR-182 antagomir enhanced the Nav1.7 expression at both mRNA and protein level in L4-6 DRGs, companied with the generation of mechanical hypersensitivity in naïve rats. Collectively, we concluded that miR-182 can alleviate SNI- induced neuropathic pain through regulating Nav1.7 in rats.
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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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Abstract
Erythromelalgia is a rare syndrome characterized by the intermittent or, less commonly, by the permanent occurrence of extremely painful hyperperfused skin areas mainly located in the distal extremities. Primary erythromelalgia is nowadays considered to be a genetically determined neuropathic disorder affecting SCN9A, SCN10A, and SCN11A coding for NaV1.7, NaV1.8, and NaV1.9 neuronal sodium channels. Secondary forms might be associated with myeloproliferative disorders, connective tissue disease, cancer, infections, and poisoning. Between the pain episodes, the affected skin areas are usually asymptomatic, but there are patients with typical features of acrocyanosis and/or Raynaud's phenomenon preceding or occurring in between the episodes of erythromelalgia. Diagnosis is made by ascertaining the typical clinical features. Thereafter, the differentiation between primary and secondary forms should be made. Genetic testing is recommended, especially in premature cases and in cases of family clustering in specialized genetic institutions after genetic counselling. Multimodal therapeutic intervention aims toward attenuation of pain and improvement of the patient's quality of life. For this purpose, a wide variety of nonpharmacological approaches and pharmacological substances for topical and systemic use have been proposed, which are usually applied individually in a step-by-step approach. Prognosis mainly depends on the underlying condition and the ability of the patients and their relatives to cope with the disease.
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Affiliation(s)
| | | | - Jutta Gisela Richter
- 2 Poliklinik, Funktionsbereich und Hiller Forschungszentrum für Rheumatologie, Medizinische Fakultät, Universitätsklinikum Düsseldorf, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
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Wadhawan S, Pant S, Golhar R, Kirov S, Thompson J, Jacobsen L, Qureshi I, Ajroud-Driss S, Freeman R, Simpson DM, Smith AG, Hoke A, Bristow LJ. Na V channel variants in patients with painful and nonpainful peripheral neuropathy. NEUROLOGY-GENETICS 2017; 3:e207. [PMID: 29264398 PMCID: PMC5732007 DOI: 10.1212/nxg.0000000000000207] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 10/02/2017] [Indexed: 12/21/2022]
Abstract
Objective: To examine the incidence of nonsynonymous missense variants in SCN9A (NaV1.7), SCN10A (NaV1.8), and SCN11A (NaV1.9) in patients with painful and nonpainful peripheral neuropathy. Methods: Next-generation sequencing was performed on 457 patient DNA samples provided by the Peripheral Neuropathy Research Registry (PNRR). The patient diagnosis was as follows: 278 idiopathic peripheral neuropathy (67% painful and 33% nonpainful) and 179 diabetic distal polyneuropathy (77% painful and 23% nonpainful). Results: We identified 36 (SCN9A), 31 (SCN10A), and 15 (SCN11A) nonsynonymous missense variants, with 47.7% of patients carrying a low-frequency (minor allele frequency <5%) missense variant in at least 1 gene. The incidence of previously reported gain-of-function missense variants was low (≤3%), and these were detected in patients with and without pain. There were no significant differences in missense variant allele frequencies of any gene, or SCN9A haplotype frequencies, between PNRR patients with painful or nonpainful peripheral neuropathy. PNRR patient SCN9A and SCN11A missense variant allele frequencies were not significantly different from the Exome Variant Server, European American (EVS-EA) reference population. For SCN10A, there was a significant increase in the alternate allele frequency of the common variant p.V1073A and low-frequency variant pS509P in PNRR patients compared with EVS-EA and the 1000 Genomes European reference populations. Conclusions: These results suggest that identification of a genetically defined subpopulation for testing of NaV1.7 inhibitors in patients with peripheral neuropathy is unlikely and that additional factors, beyond expression of previously reported disease “mutations,” are more important for the development of painful neuropathy than previously discussed.
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Affiliation(s)
- Samir Wadhawan
- Department of Translational Biomarkers and Computational Genomics (S.W., S.P., R.G., S.K., J.T.), Bristol-Myers Squibb, Hopewell Site, Pennington, NJ; Department of Genetically Defined Diseases Discovery Biology (L.J.B.), Bristol-Myers Squibb, Wallingford, CT; Department of Innovative Clinical Development (I.Q., L.J.), Bristol-Myers Squibb, Lawrenceville, Princeton, NJ; Department of Neurology (S.A.-D.), Northwestern Medical Faculty Foundation, Chicago, IL; Department of Neurology (R.F.), Beth Israel Medical Center, Harvard School of Medicine, Boston, MA; Department of Neurology (D.M.S.), Icahn School of Medicine at Mount Sinai Medical Center, New York, NY; Department of Neurology (A.G.S.), University of Utah School of Medicine, Salt Lake City, UT; Department of Neurology (A.H.), Johns Hopkins University, Baltimore, MD. S.P. is currently affiliated with Biocon Bristol-Myers Squibb Research Center, Bangalore, India
| | - Saumya Pant
- Department of Translational Biomarkers and Computational Genomics (S.W., S.P., R.G., S.K., J.T.), Bristol-Myers Squibb, Hopewell Site, Pennington, NJ; Department of Genetically Defined Diseases Discovery Biology (L.J.B.), Bristol-Myers Squibb, Wallingford, CT; Department of Innovative Clinical Development (I.Q., L.J.), Bristol-Myers Squibb, Lawrenceville, Princeton, NJ; Department of Neurology (S.A.-D.), Northwestern Medical Faculty Foundation, Chicago, IL; Department of Neurology (R.F.), Beth Israel Medical Center, Harvard School of Medicine, Boston, MA; Department of Neurology (D.M.S.), Icahn School of Medicine at Mount Sinai Medical Center, New York, NY; Department of Neurology (A.G.S.), University of Utah School of Medicine, Salt Lake City, UT; Department of Neurology (A.H.), Johns Hopkins University, Baltimore, MD. S.P. is currently affiliated with Biocon Bristol-Myers Squibb Research Center, Bangalore, India
| | - Ryan Golhar
- Department of Translational Biomarkers and Computational Genomics (S.W., S.P., R.G., S.K., J.T.), Bristol-Myers Squibb, Hopewell Site, Pennington, NJ; Department of Genetically Defined Diseases Discovery Biology (L.J.B.), Bristol-Myers Squibb, Wallingford, CT; Department of Innovative Clinical Development (I.Q., L.J.), Bristol-Myers Squibb, Lawrenceville, Princeton, NJ; Department of Neurology (S.A.-D.), Northwestern Medical Faculty Foundation, Chicago, IL; Department of Neurology (R.F.), Beth Israel Medical Center, Harvard School of Medicine, Boston, MA; Department of Neurology (D.M.S.), Icahn School of Medicine at Mount Sinai Medical Center, New York, NY; Department of Neurology (A.G.S.), University of Utah School of Medicine, Salt Lake City, UT; Department of Neurology (A.H.), Johns Hopkins University, Baltimore, MD. S.P. is currently affiliated with Biocon Bristol-Myers Squibb Research Center, Bangalore, India
| | - Stefan Kirov
- Department of Translational Biomarkers and Computational Genomics (S.W., S.P., R.G., S.K., J.T.), Bristol-Myers Squibb, Hopewell Site, Pennington, NJ; Department of Genetically Defined Diseases Discovery Biology (L.J.B.), Bristol-Myers Squibb, Wallingford, CT; Department of Innovative Clinical Development (I.Q., L.J.), Bristol-Myers Squibb, Lawrenceville, Princeton, NJ; Department of Neurology (S.A.-D.), Northwestern Medical Faculty Foundation, Chicago, IL; Department of Neurology (R.F.), Beth Israel Medical Center, Harvard School of Medicine, Boston, MA; Department of Neurology (D.M.S.), Icahn School of Medicine at Mount Sinai Medical Center, New York, NY; Department of Neurology (A.G.S.), University of Utah School of Medicine, Salt Lake City, UT; Department of Neurology (A.H.), Johns Hopkins University, Baltimore, MD. S.P. is currently affiliated with Biocon Bristol-Myers Squibb Research Center, Bangalore, India
| | - John Thompson
- Department of Translational Biomarkers and Computational Genomics (S.W., S.P., R.G., S.K., J.T.), Bristol-Myers Squibb, Hopewell Site, Pennington, NJ; Department of Genetically Defined Diseases Discovery Biology (L.J.B.), Bristol-Myers Squibb, Wallingford, CT; Department of Innovative Clinical Development (I.Q., L.J.), Bristol-Myers Squibb, Lawrenceville, Princeton, NJ; Department of Neurology (S.A.-D.), Northwestern Medical Faculty Foundation, Chicago, IL; Department of Neurology (R.F.), Beth Israel Medical Center, Harvard School of Medicine, Boston, MA; Department of Neurology (D.M.S.), Icahn School of Medicine at Mount Sinai Medical Center, New York, NY; Department of Neurology (A.G.S.), University of Utah School of Medicine, Salt Lake City, UT; Department of Neurology (A.H.), Johns Hopkins University, Baltimore, MD. S.P. is currently affiliated with Biocon Bristol-Myers Squibb Research Center, Bangalore, India
| | - Leslie Jacobsen
- Department of Translational Biomarkers and Computational Genomics (S.W., S.P., R.G., S.K., J.T.), Bristol-Myers Squibb, Hopewell Site, Pennington, NJ; Department of Genetically Defined Diseases Discovery Biology (L.J.B.), Bristol-Myers Squibb, Wallingford, CT; Department of Innovative Clinical Development (I.Q., L.J.), Bristol-Myers Squibb, Lawrenceville, Princeton, NJ; Department of Neurology (S.A.-D.), Northwestern Medical Faculty Foundation, Chicago, IL; Department of Neurology (R.F.), Beth Israel Medical Center, Harvard School of Medicine, Boston, MA; Department of Neurology (D.M.S.), Icahn School of Medicine at Mount Sinai Medical Center, New York, NY; Department of Neurology (A.G.S.), University of Utah School of Medicine, Salt Lake City, UT; Department of Neurology (A.H.), Johns Hopkins University, Baltimore, MD. S.P. is currently affiliated with Biocon Bristol-Myers Squibb Research Center, Bangalore, India
| | - Irfan Qureshi
- Department of Translational Biomarkers and Computational Genomics (S.W., S.P., R.G., S.K., J.T.), Bristol-Myers Squibb, Hopewell Site, Pennington, NJ; Department of Genetically Defined Diseases Discovery Biology (L.J.B.), Bristol-Myers Squibb, Wallingford, CT; Department of Innovative Clinical Development (I.Q., L.J.), Bristol-Myers Squibb, Lawrenceville, Princeton, NJ; Department of Neurology (S.A.-D.), Northwestern Medical Faculty Foundation, Chicago, IL; Department of Neurology (R.F.), Beth Israel Medical Center, Harvard School of Medicine, Boston, MA; Department of Neurology (D.M.S.), Icahn School of Medicine at Mount Sinai Medical Center, New York, NY; Department of Neurology (A.G.S.), University of Utah School of Medicine, Salt Lake City, UT; Department of Neurology (A.H.), Johns Hopkins University, Baltimore, MD. S.P. is currently affiliated with Biocon Bristol-Myers Squibb Research Center, Bangalore, India
| | - Senda Ajroud-Driss
- Department of Translational Biomarkers and Computational Genomics (S.W., S.P., R.G., S.K., J.T.), Bristol-Myers Squibb, Hopewell Site, Pennington, NJ; Department of Genetically Defined Diseases Discovery Biology (L.J.B.), Bristol-Myers Squibb, Wallingford, CT; Department of Innovative Clinical Development (I.Q., L.J.), Bristol-Myers Squibb, Lawrenceville, Princeton, NJ; Department of Neurology (S.A.-D.), Northwestern Medical Faculty Foundation, Chicago, IL; Department of Neurology (R.F.), Beth Israel Medical Center, Harvard School of Medicine, Boston, MA; Department of Neurology (D.M.S.), Icahn School of Medicine at Mount Sinai Medical Center, New York, NY; Department of Neurology (A.G.S.), University of Utah School of Medicine, Salt Lake City, UT; Department of Neurology (A.H.), Johns Hopkins University, Baltimore, MD. S.P. is currently affiliated with Biocon Bristol-Myers Squibb Research Center, Bangalore, India
| | - Roy Freeman
- Department of Translational Biomarkers and Computational Genomics (S.W., S.P., R.G., S.K., J.T.), Bristol-Myers Squibb, Hopewell Site, Pennington, NJ; Department of Genetically Defined Diseases Discovery Biology (L.J.B.), Bristol-Myers Squibb, Wallingford, CT; Department of Innovative Clinical Development (I.Q., L.J.), Bristol-Myers Squibb, Lawrenceville, Princeton, NJ; Department of Neurology (S.A.-D.), Northwestern Medical Faculty Foundation, Chicago, IL; Department of Neurology (R.F.), Beth Israel Medical Center, Harvard School of Medicine, Boston, MA; Department of Neurology (D.M.S.), Icahn School of Medicine at Mount Sinai Medical Center, New York, NY; Department of Neurology (A.G.S.), University of Utah School of Medicine, Salt Lake City, UT; Department of Neurology (A.H.), Johns Hopkins University, Baltimore, MD. S.P. is currently affiliated with Biocon Bristol-Myers Squibb Research Center, Bangalore, India
| | - David M Simpson
- Department of Translational Biomarkers and Computational Genomics (S.W., S.P., R.G., S.K., J.T.), Bristol-Myers Squibb, Hopewell Site, Pennington, NJ; Department of Genetically Defined Diseases Discovery Biology (L.J.B.), Bristol-Myers Squibb, Wallingford, CT; Department of Innovative Clinical Development (I.Q., L.J.), Bristol-Myers Squibb, Lawrenceville, Princeton, NJ; Department of Neurology (S.A.-D.), Northwestern Medical Faculty Foundation, Chicago, IL; Department of Neurology (R.F.), Beth Israel Medical Center, Harvard School of Medicine, Boston, MA; Department of Neurology (D.M.S.), Icahn School of Medicine at Mount Sinai Medical Center, New York, NY; Department of Neurology (A.G.S.), University of Utah School of Medicine, Salt Lake City, UT; Department of Neurology (A.H.), Johns Hopkins University, Baltimore, MD. S.P. is currently affiliated with Biocon Bristol-Myers Squibb Research Center, Bangalore, India
| | - A Gordon Smith
- Department of Translational Biomarkers and Computational Genomics (S.W., S.P., R.G., S.K., J.T.), Bristol-Myers Squibb, Hopewell Site, Pennington, NJ; Department of Genetically Defined Diseases Discovery Biology (L.J.B.), Bristol-Myers Squibb, Wallingford, CT; Department of Innovative Clinical Development (I.Q., L.J.), Bristol-Myers Squibb, Lawrenceville, Princeton, NJ; Department of Neurology (S.A.-D.), Northwestern Medical Faculty Foundation, Chicago, IL; Department of Neurology (R.F.), Beth Israel Medical Center, Harvard School of Medicine, Boston, MA; Department of Neurology (D.M.S.), Icahn School of Medicine at Mount Sinai Medical Center, New York, NY; Department of Neurology (A.G.S.), University of Utah School of Medicine, Salt Lake City, UT; Department of Neurology (A.H.), Johns Hopkins University, Baltimore, MD. S.P. is currently affiliated with Biocon Bristol-Myers Squibb Research Center, Bangalore, India
| | - Ahmet Hoke
- Department of Translational Biomarkers and Computational Genomics (S.W., S.P., R.G., S.K., J.T.), Bristol-Myers Squibb, Hopewell Site, Pennington, NJ; Department of Genetically Defined Diseases Discovery Biology (L.J.B.), Bristol-Myers Squibb, Wallingford, CT; Department of Innovative Clinical Development (I.Q., L.J.), Bristol-Myers Squibb, Lawrenceville, Princeton, NJ; Department of Neurology (S.A.-D.), Northwestern Medical Faculty Foundation, Chicago, IL; Department of Neurology (R.F.), Beth Israel Medical Center, Harvard School of Medicine, Boston, MA; Department of Neurology (D.M.S.), Icahn School of Medicine at Mount Sinai Medical Center, New York, NY; Department of Neurology (A.G.S.), University of Utah School of Medicine, Salt Lake City, UT; Department of Neurology (A.H.), Johns Hopkins University, Baltimore, MD. S.P. is currently affiliated with Biocon Bristol-Myers Squibb Research Center, Bangalore, India
| | - Linda J Bristow
- Department of Translational Biomarkers and Computational Genomics (S.W., S.P., R.G., S.K., J.T.), Bristol-Myers Squibb, Hopewell Site, Pennington, NJ; Department of Genetically Defined Diseases Discovery Biology (L.J.B.), Bristol-Myers Squibb, Wallingford, CT; Department of Innovative Clinical Development (I.Q., L.J.), Bristol-Myers Squibb, Lawrenceville, Princeton, NJ; Department of Neurology (S.A.-D.), Northwestern Medical Faculty Foundation, Chicago, IL; Department of Neurology (R.F.), Beth Israel Medical Center, Harvard School of Medicine, Boston, MA; Department of Neurology (D.M.S.), Icahn School of Medicine at Mount Sinai Medical Center, New York, NY; Department of Neurology (A.G.S.), University of Utah School of Medicine, Salt Lake City, UT; Department of Neurology (A.H.), Johns Hopkins University, Baltimore, MD. S.P. is currently affiliated with Biocon Bristol-Myers Squibb Research Center, Bangalore, India
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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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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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Shao J, Cao J, Wang J, Ren X, Su S, Li M, Li Z, Zhao Q, Zang W. MicroRNA-30b regulates expression of the sodium channel Nav1.7 in nerve injury-induced neuropathic pain in the rat. Mol Pain 2016; 12:12/0/1744806916671523. [PMID: 27765894 PMCID: PMC5081156 DOI: 10.1177/1744806916671523] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Accepted: 08/03/2016] [Indexed: 01/08/2023] Open
Abstract
Voltage-gated sodium channels, which are involved in pain pathways, have emerged as major targets for therapeutic intervention in pain disorders. Nav1.7, the tetrodotoxin-sensitive voltage-gated sodium channel isoform encoded by SCN9A and predominantly expressed in pain-sensing neurons in the dorsal root ganglion, plays a crucial role in nociception. MicroRNAs are highly conserved, small non-coding RNAs. Through binding to the 3′ untranslated region of their target mRNAs, microRNAs induce the cleavage and/or inhibition of protein translation. Based on bioinformatics analysis using TargetScan software, we determined that miR-30b directly targets SCN9A. To investigate the roles of Nav1.7 and miR-30b in neuropathic pain, we examined changes in the expression of Nav1.7 in the dorsal root ganglion by miR-30b over-expression or knockdown in rats with spared nerve injury. Our results demonstrated that the expression of miR-30b and Nav1.7 was down-regulated and up-regulated, respectively, in the dorsal root ganglion of spared nerve injury rats. MiR-30b over-expression in spared nerve injury rats inhibited SCN9A transcription, resulting in pain relief. In addition, miR-30b knockdown significantly increased hypersensitivity to pain in naive rats. We also observed that miR-30b decreased Nav1.7 expression in PC12 cells. Taken together, our results suggest that miR-30b plays an important role in neuropathic pain by regulating Nav1.7 expression. Therefore, miR-30b may be a promising target for the treatment of chronic neuropathic pain.
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Affiliation(s)
- Jinping Shao
- Department of Anatomy, Basic Medical College, Zhengzhou University, Zhengzhou, China
| | - Jing Cao
- Department of Anatomy, Basic Medical College, Zhengzhou University, Zhengzhou, China
| | - Jiannan Wang
- Department of Anatomy, Basic Medical College, Zhengzhou University, Zhengzhou, China
| | - Xiuhua Ren
- Department of Anatomy, Basic Medical College, Zhengzhou University, Zhengzhou, China
| | - Songxue Su
- Department of Anatomy, Basic Medical College, Zhengzhou University, Zhengzhou, China
| | - Ming Li
- Department of Anatomy, Basic Medical College, Zhengzhou University, Zhengzhou, China
| | - Zhihua Li
- Department of Anatomy, Basic Medical College, Zhengzhou University, Zhengzhou, China
| | - Qingzan Zhao
- Department of Anatomy, Basic Medical College, Zhengzhou University, Zhengzhou, China
| | - Weidong Zang
- Department of Anatomy, Basic Medical College, Zhengzhou University, Zhengzhou, China
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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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Tibbs GR, Posson DJ, Goldstein PA. Voltage-Gated Ion Channels in the PNS: Novel Therapies for Neuropathic Pain? Trends Pharmacol Sci 2016; 37:522-542. [DOI: 10.1016/j.tips.2016.05.002] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 03/24/2016] [Accepted: 05/03/2016] [Indexed: 12/19/2022]
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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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Motin L, Durek T, Adams DJ. Modulation of human Nav1.7 channel gating by synthetic α-scorpion toxin OD1 and its analogs. Channels (Austin) 2015; 10:139-47. [PMID: 26646206 DOI: 10.1080/19336950.2015.1120392] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Nine different voltage-gated sodium channel isoforms are responsible for inducing and propagating action potentials in the mammalian nervous system. The Nav1.7 channel isoform plays an important role in conducting nociceptive signals. Specific mutations of this isoform may impair gating behavior of the channel resulting in several pain syndromes. In addition to channel mutations, similar or opposite changes in gating may be produced by spider and scorpion toxins binding to different parts of the voltage-gated sodium channel. In the present study, we analyzed the effects of the α-scorpion toxin OD1 and 2 synthetic toxin analogs on the gating properties of the Nav1.7 sodium channel. All toxins potently inhibited channel inactivation, however, both toxin analogs showed substantially increased potency by more than one order of magnitude when compared with that of wild-type OD1. The decay phase of the whole-cell Na(+) current was substantially slower in the presence of toxins than in their absence. Single-channel recordings in the presence of the toxins revealed that Na(+) current inactivation slowed due to prolonged flickering of the channel between open and closed states. Our findings support the voltage-sensor trapping model of α-scorpion toxin action, in which the toxin prevents a conformational change in the domain IV voltage sensor that normally leads to fast channel inactivation.
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Affiliation(s)
- Leonid Motin
- a Health Innovations Research Institute, RMIT University , Melbourne , Victoria, Australia
| | - Thomas Durek
- b Division of Chemistry & Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane , Queensland, Australia
| | - David J Adams
- a Health Innovations Research Institute, RMIT University , Melbourne , Victoria, Australia
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Abstract
• Individual variability in pain perception and differences in the efficacy of analgesic drugs are complex phenomena and are partly genetically predetermined. • Analgesics act in various ways on the peripheral and central pain pathways and are regarded as one of the most valuable but equally dangerous groups of medications. • While pharmacokinetic properties of drugs, metabolism in particular, have been scrutinised by genotype–phenotype correlation studies, the clinical significance of inherited variants in genes governing pharmacodynamics of analgesics remains largely unexplored (apart from the µ-opioid receptor). • Lack of replication of the findings from one study to another makes meaningful personalised analgesic regime still a distant future. • This narrative review will focus on findings related to pharmacogenetics of commonly used analgesic medications and highlight authors’ views on future clinical implications of pharmacogenetics in the context of pharmacological treatment of chronic pain.
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Affiliation(s)
- Roman Cregg
- UCL Centre for Anaesthesia, Critical Care & Pain Medicine, London, UK ; Royal Marsden NHS Foundation Trust, London, UK
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Duan G, Guo S, Zhang Y, Ying Y, Huang P, Wang Q, Zhang L, Zhang X. The Effect of SCN9A Variation on Basal Pain Sensitivity in the General Population: An Experimental Study in Young Women. THE JOURNAL OF PAIN 2015; 16:971-80. [DOI: 10.1016/j.jpain.2015.06.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 06/09/2015] [Accepted: 06/24/2015] [Indexed: 10/23/2022]
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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: 68] [Impact Index Per Article: 7.6] [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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Miceli F, Soldovieri MV, Ambrosino P, De Maria M, Manocchio L, Medoro A, Taglialatela M. Molecular pathophysiology and pharmacology of the voltage-sensing module of neuronal ion channels. Front Cell Neurosci 2015; 9:259. [PMID: 26236192 PMCID: PMC4502356 DOI: 10.3389/fncel.2015.00259] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 06/22/2015] [Indexed: 12/19/2022] Open
Abstract
Voltage-gated ion channels (VGICs) are membrane proteins that switch from a closed to open state in response to changes in membrane potential, thus enabling ion fluxes across the cell membranes. The mechanism that regulate the structural rearrangements occurring in VGICs in response to changes in membrane potential still remains one of the most challenging topic of modern biophysics. Na+, Ca2+ and K+ voltage-gated channels are structurally formed by the assembly of four similar domains, each comprising six transmembrane segments. Each domain can be divided into two main regions: the Pore Module (PM) and the Voltage-Sensing Module (VSM). The PM (helices S5 and S6 and intervening linker) is responsible for gate opening and ion selectivity; by contrast, the VSM, comprising the first four transmembrane helices (S1–S4), undergoes the first conformational changes in response to membrane voltage variations. In particular, the S4 segment of each domain, which contains several positively charged residues interspersed with hydrophobic amino acids, is located within the membrane electric field and plays an essential role in voltage sensing. In neurons, specific gating properties of each channel subtype underlie a variety of biological events, ranging from the generation and propagation of electrical impulses, to the secretion of neurotransmitters and to the regulation of gene expression. Given the important functional role played by the VSM in neuronal VGICs, it is not surprising that various VSM mutations affecting the gating process of these channels are responsible for human diseases, and that compounds acting on the VSM have emerged as important investigational tools with great therapeutic potential. In the present review we will briefly describe the most recent discoveries concerning how the VSM exerts its function, how genetically inherited diseases caused by mutations occurring in the VSM affects gating in VGICs, and how several classes of drugs and toxins selectively target the VSM.
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Affiliation(s)
- Francesco Miceli
- Department of Neuroscience, University of Naples Federico II Naples, Italy
| | | | - Paolo Ambrosino
- Department of Medicine and Health Sciences, University of Molise Campobasso, Italy
| | - Michela De Maria
- Department of Medicine and Health Sciences, University of Molise Campobasso, Italy
| | - Laura Manocchio
- Department of Medicine and Health Sciences, University of Molise Campobasso, Italy
| | - Alessandro Medoro
- Department of Medicine and Health Sciences, University of Molise Campobasso, Italy
| | - Maurizio Taglialatela
- Department of Neuroscience, University of Naples Federico II Naples, Italy ; Department of Medicine and Health Sciences, University of Molise Campobasso, Italy
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Amarouch MY, Abriel H. Cellular hyper-excitability caused by mutations that alter the activation process of voltage-gated sodium channels. Front Physiol 2015; 6:45. [PMID: 25741286 PMCID: PMC4330716 DOI: 10.3389/fphys.2015.00045] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 01/30/2015] [Indexed: 12/19/2022] Open
Abstract
Voltage-gated sodium channels (Nav) are widely expressed as macro-molecular complexes in both excitable and non-excitable tissues. In excitable tissues, the upstroke of the action potential is the result of the passage of a large and rapid influx of sodium ions through these channels. NaV dysfunction has been associated with an increasingly wide range of neurological, muscular and cardiac disorders. The purpose of this review is to summarize the recently identified sodium channel mutations that are linked to hyper-excitability phenotypes and associated with the alteration of the activation process of voltage gated sodium channels. Indeed, several clinical manifestations that demonstrate an alteration of tissue excitability were recently shown to be strongly associated with the presence of mutations that affect the activation process of the Nav. These emerging genotype-phenotype correlations have expanded the clinical spectrum of sodium channelopathies to include disorders which feature a hyper-excitability phenotype that may or may not be associated with a cardiomyopathy. The p.I141V mutation in SCN4A and SCN5A, as well as its homologous p.I136V mutation in SCN9A, are interesting examples of mutations that have been linked to inherited hyperexcitability myotonia, exercise-induced polymorphic ventricular arrhythmias and erythromelalgia, respectively. Regardless of which sodium channel isoform is investigated, the substitution of the isoleucine to valine in the locus 141 induces similar modifications in the biophysical properties of the Nav by shifting the voltage-dependence of steady state activation toward more negative potentials.
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Affiliation(s)
- Mohamed-Yassine Amarouch
- Materials, Natural Substances, Environment and Modeling Laboratory, Multidisciplinary Faculty of Taza, University of Sidi Mohamed Ben Abdellah-Fes Taza, Morocco
| | - Hugues Abriel
- Department of Clinical Research, University of Bern Bern, Switzerland
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Stadler T, O'Reilly AO, Lampert A. Erythromelalgia mutation Q875E Stabilizes the activated state of sodium channel Nav1.7. J Biol Chem 2015; 290:6316-25. [PMID: 25575597 DOI: 10.1074/jbc.m114.605899] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The human voltage-gated sodium channel Nav1.7 plays a crucial role in transmission of noxious stimuli. The inherited pain disorder erythromelalgia (IEM) has been linked to Nav1.7 gain-of-function mutations. Here we show that the IEM-associated Q875E mutation located on the pore module of Nav1.7 produces a large hyperpolarizing shift (-18 mV) in the voltage dependence of activation. Three-dimensional homology modeling indicates that the side chains of Gln-875 and the gating charge Arg-214 of the domain I voltage sensor are spatially close in the activated conformation of the channel. We verified this proximity by using an engineered disulfide bridge approach. The Q875E mutation introduces a negative charge that may modify the local electrical field experienced by the voltage sensor and, upon activation, interact directly via a salt bridge with the Arg-214 gating charge residue. Together these processes could promote transition to, and stabilization of, the domain I voltage sensor in the activated conformation and thus produce the observed gain of function. In support of this hypothesis, an increase in the extracellular concentration of Ca(2+) or Mg(2+) reverted the voltage dependence of activation of the IEM mutant to near WT values, suggesting a cation-mediated electrostatic screening of the proposed interaction between Q875E and Arg-214.
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Affiliation(s)
- Theresa Stadler
- From the Institute of Physiology and Pathophysiology, Friedrich-Alexander Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Andrias O O'Reilly
- From the Institute of Physiology and Pathophysiology, Friedrich-Alexander Universität Erlangen-Nürnberg, 91054 Erlangen, Germany, the School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, Merseyside L3 3AF, United Kingdom, and
| | - Angelika Lampert
- From the Institute of Physiology and Pathophysiology, Friedrich-Alexander Universität Erlangen-Nürnberg, 91054 Erlangen, Germany, the Institute of Physiology, RWTH Aachen University Hospital, 52074 Aachen, Germany
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Waxman SG, Merkies ISJ, Gerrits MM, Dib-Hajj SD, Lauria G, Cox JJ, Wood JN, Woods CG, Drenth JPH, Faber CG. Sodium channel genes in pain-related disorders: phenotype–genotype associations and recommendations for clinical use. Lancet Neurol 2014; 13:1152-1160. [DOI: 10.1016/s1474-4422(14)70150-4] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Zhang Z, Schmelz M, Segerdahl M, Quiding H, Centerholt C, Juréus A, Carr TH, Whiteley J, Salter H, Kvernebo MS, Ørstavik K, Helås T, Kleggetveit IP, Lunden LK, Jørum E. Exonic mutations in SCN9A (NaV1.7) are found in a minority of patients with erythromelalgia. Scand J Pain 2014; 5:217-225. [DOI: 10.1016/j.sjpain.2014.09.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 09/03/2014] [Indexed: 10/24/2022]
Abstract
Abstract
Background and aim
“Gain-of-function” mutations in voltage-gated sodium channel NaV1.7 have been linked to erythromelalgia (EM), characterized by painful hot and red hands and feet. We investigated the proportion of patients with EM that carry a mutation in NaV1.7 or in other pain-related genes and studied possible clinical differences.
Methods
In this study, 48 patients with EM were screened for mutations in a total of 29 candidate genes, including all sodium channel subunits, transient receptor potential channels (TRPA1, TRPV1, TRPM8), neurotrophic factors (NGF, NGFR, BDNF, GDNF, NTRK1 and WNK1) and other known pain-related genes (CACNG2, KCNS1, COMT, P2RX3, TAC1, TACR1), using a combination of next generation sequencing and classical Sanger sequencing.
Results
In 7/48 patients protein-modifying mutations of NaV1.7 (P187L, I228M, I848T (n = 4) and N1245S) were identified. Patients with the I848T mutation could be identified clinically based on early onset and severity of the disease. In contrast, there were no clinical characteristics that differentiated the other patients with NaV1.7 mutation from those patients without. We also found more than twenty rare protein-modifying genetic variants in the genes coding for sodium channels (NaV1.8, NaV1.9, NaV1.6, NaV1.5, NaV2.1, SCN1B, SCN3B), transient receptor potential channel (TRPA1, TRPV1), and other pain-related targets (WNK1 and NGFR).
Conclusion
We conclude that functionally characterized mutations of NaV1.7 (I848T) are present only in a minority of patient with EM. Albeit the majority of patients (27/48) carried rare protein-modifying mutations the vast majority of those will most probably not be causally linked to their disease.
Implications
The key question remaining to be solved is the possible role of rare variants of NaV1.8, NaV1.9, or beta-subunits in provoking chronic pain conditions or even EM.
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Affiliation(s)
| | - Martin Schmelz
- Department of Anesthesiology Mannheim , Heidelberg University , Heidelberg , Germany
| | - Märta Segerdahl
- AstraZeneca R&D , Södertälje , Sweden
- Department of Physiology and Pharmacology , Karolinska Institute , Stockholm , Sweden
| | | | | | | | | | | | - Hugh Salter
- AstraZeneca Translational Science Centre , Department of Clinical Neuroscience , Karolinska Institutet , Karolinska , Sweden
| | | | - Kristin Ørstavik
- Section of Clinical Neurophysiology , Department of Neurology , Oslo University Hospital-Rikshospitalet , Oslo , Norway
| | - Tormod Helås
- Section of Clinical Neurophysiology , Department of Neurology , Oslo University Hospital-Rikshospitalet , Oslo , Norway
| | - Inge-Petter Kleggetveit
- Section of Clinical Neurophysiology , Department of Neurology , Oslo University Hospital-Rikshospitalet , Oslo , Norway
| | - Lars Kristian Lunden
- Section of Clinical Neurophysiology , Department of Neurology , Oslo University Hospital-Rikshospitalet , Oslo , Norway
| | - Ellen Jørum
- Section of Clinical Neurophysiology , Department of Neurology , Oslo University Hospital-Rikshospitalet , Oslo , Norway
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Harrer JU, Üçeyler N, Doppler K, Fischer TZ, Dib-Hajj SD, Waxman SG, Sommer C. Neuropathic pain in two-generation twins carrying the sodium channel Nav1.7 functional variant R1150W. Pain 2014; 155:2199-203. [DOI: 10.1016/j.pain.2014.08.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 06/04/2014] [Accepted: 08/05/2014] [Indexed: 10/24/2022]
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43
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Mutational Consequences of Aberrant Ion Channels in Neurological Disorders. J Membr Biol 2014; 247:1083-127. [DOI: 10.1007/s00232-014-9716-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Accepted: 07/25/2014] [Indexed: 12/25/2022]
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Themistocleous AC, Ramirez JD, Serra J, Bennett DLH. The clinical approach to small fibre neuropathy and painful channelopathy. Pract Neurol 2014; 14:368-79. [PMID: 24778270 PMCID: PMC4251302 DOI: 10.1136/practneurol-2013-000758] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Small fibre neuropathy (SFN) is characterised by structural injury selectively affecting small diameter sensory and/or autonomic axons. The clinical presentation is dominated by pain. SFN complicates a number of common diseases such as diabetes mellitus and is likely to be increasingly encountered. The diagnosis of SFN is demanding as clinical features can be vague and nerve conduction studies normal. New diagnostic techniques, in particular measurement of intraepidermal nerve fibre density, have significantly improved the diagnostic efficiency of SFN. Management is focused on the treatment of the underlying cause and analgesia, as there is no neuroprotective therapy. A recent and significant advance is the finding that a proportion of cases labelled as idiopathic SFN are in fact associated with gain of function mutations of the voltage-gated sodium channels Nav1.7 and Nav1.8 (encoded by the genes SCN9A and SCN10A, respectively). There is a further group of heritable painful conditions in which gain of function mutations in ion channels alter excitability of sensory neurones but do not cause frank axon degeneration; these include mutations in Nav1.7 (causing erythromelalgia and paroxysmal extreme pain disorder) and TRPA1 (resulting in familial episodic pain disorder). These conditions are exceptionally rare but have provided great insight into the nociceptive system as well as yielding potential analgesic drug targets. In patients with no pre-existing risk factor, the investigation of an underlying cause of SFN should be systematic and appropriate for the patient population. In this review, we focus on how to incorporate recent developments in the diagnosis and pathophysiology of SFN into clinical practice.
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Affiliation(s)
| | - Juan D Ramirez
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, Oxfordshire, UK
| | - Jordi Serra
- Neuroscience Technologies, Parc Científic de Barcelona, Barcelona, Spain Department of Neurology, MC Mutual, Barcelona, Spain
| | - David L H Bennett
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, Oxfordshire, UK
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Ahogo KC, Menet V, Modiano P, Lasek A. Crises de pleurs inconsolables révélatrices d’une érythermalgie primitive chez un nourrisson de 6 mois. Arch Pediatr 2014; 21:299-301. [DOI: 10.1016/j.arcped.2013.12.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2013] [Revised: 08/07/2013] [Accepted: 12/09/2013] [Indexed: 10/25/2022]
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Heimann D, Lötsch J, Hummel T, Doehring A, Oertel BG. Linkage between increased nociception and olfaction via a SCN9A haplotype. PLoS One 2013; 8:e68654. [PMID: 23874707 PMCID: PMC3707874 DOI: 10.1371/journal.pone.0068654] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 05/30/2013] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND AND AIMS Mutations reducing the function of Nav1.7 sodium channels entail diminished pain perception and olfactory acuity, suggesting a link between nociception and olfaction at ion channel level. We hypothesized that if such link exists, it should work in both directions and gain-of-function Nav1.7 mutations known to be associated with increased pain perception should also increase olfactory acuity. METHODS SCN9A variants were assessed known to enhance pain perception and found more frequently in the average population. Specifically, carriers of SCN9A variants rs41268673C>A (P610T; n = 14) or rs6746030C>T (R1150W; n = 21) were compared with non-carriers (n = 40). Olfactory function was quantified by assessing odor threshold, odor discrimination and odor identification using an established olfactory test. Nociception was assessed by measuring pain thresholds to experimental nociceptive stimuli (punctate and blunt mechanical pressure, heat and electrical stimuli). RESULTS The number of carried alleles of the non-mutated SCN9A haplotype rs41268673C/rs6746030C was significantly associated with the comparatively highest olfactory threshold (0 alleles: threshold at phenylethylethanol dilution step 12 of 16 (n = 1), 1 allele: 10.6±2.6 (n = 34), 2 alleles: 9.5±2.1 (n = 40)). The same SCN9A haplotype determined the pain threshold to blunt pressure stimuli (0 alleles: 21.1 N/m(2), 1 allele: 29.8±10.4 N/m(2), 2 alleles: 33.5±10.2 N/m(2)). CONCLUSIONS The findings established a working link between nociception and olfaction via Nav1.7 in the gain-of-function direction. Hence, together with the known reduced olfaction and pain in loss-of-function mutations, a bidirectional genetic functional association between nociception and olfaction exists at Nav1.7 level.
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Affiliation(s)
- Dirk Heimann
- Institute of Clinical Pharmacology, Goethe - University, Frankfurt am Main, Germany
| | - Jörn Lötsch
- Institute of Clinical Pharmacology, Goethe - University, Frankfurt am Main, Germany
- Fraunhofer Institute of Molecular Biology and Applied Ecology - Project Group Translational Medicine and Pharmacology (IME-TMP), Frankfurt am Main, Germany
| | - Thomas Hummel
- Smell and Taste Clinic, Department of Otorhinolaryngology, University of Dresden Medical School, Dresden, Germany
| | - Alexandra Doehring
- Institute of Clinical Pharmacology, Goethe - University, Frankfurt am Main, Germany
| | - Bruno G. Oertel
- Institute of Clinical Pharmacology, Goethe - University, Frankfurt am Main, Germany
- Fraunhofer Institute of Molecular Biology and Applied Ecology - Project Group Translational Medicine and Pharmacology (IME-TMP), Frankfurt am Main, Germany
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