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Pozzi E, Terribile G, Cherchi L, Di Girolamo S, Sancini G, Alberti P. Ion Channel and Transporter Involvement in Chemotherapy-Induced Peripheral Neurotoxicity. Int J Mol Sci 2024; 25:6552. [PMID: 38928257 PMCID: PMC11203899 DOI: 10.3390/ijms25126552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2024] [Revised: 06/06/2024] [Accepted: 06/11/2024] [Indexed: 06/28/2024] Open
Abstract
The peripheral nervous system can encounter alterations due to exposure to some of the most commonly used anticancer drugs (platinum drugs, taxanes, vinca alkaloids, proteasome inhibitors, thalidomide), the so-called chemotherapy-induced peripheral neurotoxicity (CIPN). CIPN can be long-lasting or even permanent, and it is detrimental for the quality of life of cancer survivors, being associated with persistent disturbances such as sensory loss and neuropathic pain at limb extremities due to a mostly sensory axonal polyneuropathy/neuronopathy. In the state of the art, there is no efficacious preventive/curative treatment for this condition. Among the reasons for this unmet clinical and scientific need, there is an uncomplete knowledge of the pathogenetic mechanisms. Ion channels and transporters are pivotal elements in both the central and peripheral nervous system, and there is a growing body of literature suggesting that they might play a role in CIPN development. In this review, we first describe the biophysical properties of these targets and then report existing data for the involvement of ion channels and transporters in CIPN, thus paving the way for new approaches/druggable targets to cure and/or prevent CIPN.
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Affiliation(s)
- Eleonora Pozzi
- Experimental Neurology Unit, School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy; (E.P.); (L.C.); (S.D.G.)
| | - Giulia Terribile
- Human Physiology Unit, School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy; (G.T.); (G.S.)
| | - Laura Cherchi
- Experimental Neurology Unit, School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy; (E.P.); (L.C.); (S.D.G.)
| | - Sara Di Girolamo
- Experimental Neurology Unit, School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy; (E.P.); (L.C.); (S.D.G.)
| | - Giulio Sancini
- Human Physiology Unit, School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy; (G.T.); (G.S.)
| | - Paola Alberti
- Experimental Neurology Unit, School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy; (E.P.); (L.C.); (S.D.G.)
- Fondazione IRCCS San Gerardo dei Tintori, 20900 Monza, Italy
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2
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Wang Q, Ye Y, Yang L, Xiao L, Liu J, Zhang W, Du G. Painful diabetic neuropathy: The role of ion channels. Biomed Pharmacother 2024; 173:116417. [PMID: 38490158 DOI: 10.1016/j.biopha.2024.116417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 03/06/2024] [Accepted: 03/06/2024] [Indexed: 03/17/2024] Open
Abstract
Painful diabetic neuropathy (PDN) is a common chronic complication of diabetes that causes neuropathic pain and negatively affects the quality of life. The management of PDN is far from satisfactory. At present, interventions are primarily focused on symptomatic treatment. Ion channel disorders are a major cause of PDN, and a complete understanding of their roles and mechanisms may provide better options for the clinical treatment of PDN. Therefore, this review summarizes the important role of ion channels in PDN and the current drug development targeting these ion channels.
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Affiliation(s)
- Qi Wang
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Centre, West China Hospital, Sichuan University, Chengdu, China; National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| | - Yifei Ye
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Centre, West China Hospital, Sichuan University, Chengdu, China; National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| | - Linghui Yang
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Centre, West China Hospital, Sichuan University, Chengdu, China; National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| | - Lifan Xiao
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Centre, West China Hospital, Sichuan University, Chengdu, China; National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| | - Jin Liu
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Centre, West China Hospital, Sichuan University, Chengdu, China; National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| | - Wensheng Zhang
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Centre, West China Hospital, Sichuan University, Chengdu, China; National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China.
| | - Guizhi Du
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Centre, West China Hospital, Sichuan University, Chengdu, China; National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China.
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3
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van Gool R, Far A, Drenthen GS, Jansen JFA, Goijen CP, Backes WH, Linden DEJ, Merkies ISJ, Faber CG, Upadhyay J, Hoeijmakers JGJ. Peripheral Pain Captured Centrally: Altered Brain Morphology on MRI in Small Fiber Neuropathy Patients With and Without an SCN9A Gene Variant. THE JOURNAL OF PAIN 2024; 25:730-741. [PMID: 37921732 DOI: 10.1016/j.jpain.2023.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 09/05/2023] [Accepted: 10/03/2023] [Indexed: 11/04/2023]
Abstract
The current study aims to characterize brain morphology of pain as reported by small fiber neuropathy (SFN) patients with or without a gain-of-function variant involving the SCN9A gene and compare these with findings in healthy controls without pain. The Neuropathic Pain Scale was used in patients with idiopathic SFN (N = 20) and SCN9A-associated SFN (N = 12) to capture pain phenotype. T1-weighted, structural magnetic resonance imaging (MRI) data were collected in patients and healthy controls (N = 21) to 1) compare cortical thickness and subcortical volumes and 2) quantify the association between severity, quality, and duration of pain with morphological properties. SCN9A-associated SFN patients showed significant (P < .017, Bonferroni corrected) higher cortical thickness in sensorimotor regions, compared to idiopathic SFN patients, while lower cortical thickness was found in more functionally diverse regions (eg, posterior cingulate cortex). SFN patient groups combined demonstrated a significant (Spearman's ρ = .44-.55, P = .005-.049) correlation among itch sensations (Neuropathic Pain Scale-7) and thickness of the left precentral gyrus, and midcingulate cortices. Significant associations were found between thalamic volumes and duration of pain (left: ρ = -.37, P = .043; right: ρ = -.40, P = .025). No associations were found between morphological properties and other pain qualities. In conclusion, in SCN9A-associated SFN, profound morphological alterations anchored within the pain matrix are present. The association between itch sensations of pain and sensorimotor and midcingulate structures provides a novel basis for further examining neurobiological underpinnings of itch in SFN. PERSPECTIVE: Cortical thickness and subcortical volume alterations in SFN patients were found in pain hubs, more profound in SCN9A-associated neuropathy, and correlated with itch and durations of pain. These findings contribute to our understanding of the pathophysiological pathways underlying chronic neuropathic pain and symptoms of itch in SFN.
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Affiliation(s)
- Raquel van Gool
- Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts; School for Mental Health and Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Limburg, The Netherlands
| | - Amir Far
- School for Mental Health and Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Limburg, The Netherlands; Department of Neurology, Maastricht University Medical Center+, Maastricht, Limburg, The Netherlands
| | - Gerhard S Drenthen
- School for Mental Health and Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Limburg, The Netherlands; Department of Radiology and Nuclear Medicine, Maastricht University Medical Center+, Maastricht, Limburg, The Netherlands
| | - Jacobus F A Jansen
- School for Mental Health and Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Limburg, The Netherlands; Department of Radiology and Nuclear Medicine, Maastricht University Medical Center+, Maastricht, Limburg, The Netherlands; Department of Electrical Engineering, Eindhoven University of Technology, Eindhoven, North Brabant, The Netherlands
| | - Celine P Goijen
- School for Mental Health and Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Limburg, The Netherlands; Department of Neurology, Maastricht University Medical Center+, Maastricht, Limburg, The Netherlands
| | - Walter H Backes
- School for Mental Health and Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Limburg, The Netherlands; Department of Radiology and Nuclear Medicine, Maastricht University Medical Center+, Maastricht, Limburg, The Netherlands
| | - David E J Linden
- School for Mental Health and Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Limburg, The Netherlands; Department of Psychiatry and Neuropsychology, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Limburg, The Netherlands
| | - Ingemar S J Merkies
- School for Mental Health and Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Limburg, The Netherlands; Department of Neurology, Maastricht University Medical Center+, Maastricht, Limburg, The Netherlands; Department of Neurology, Curaçao Medical Center, Willemstad, Kingdom of the Netherlands, Curaçao
| | - Catharina G Faber
- School for Mental Health and Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Limburg, The Netherlands; Department of Neurology, Maastricht University Medical Center+, Maastricht, Limburg, The Netherlands
| | - Jaymin Upadhyay
- Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts; Department of Psychiatry, McLean Hospital, Harvard Medical School, Belmont, Massachusetts
| | - Janneke G J Hoeijmakers
- School for Mental Health and Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Limburg, The Netherlands; Department of Neurology, Maastricht University Medical Center+, Maastricht, Limburg, The Netherlands
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4
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de Cássia Collaço R, Lammens M, Blevins C, Rodgers K, Gurau A, Yamauchi S, Kim C, Forrester J, Liu E, Ha J, Mei Y, Boehm C, Wohler E, Sobreira N, Rowe PC, Valle D, Brock MV, Bosmans F. Anxiety and dysautonomia symptoms in patients with a Na V1.7 mutation and the potential benefits of low-dose short-acting guanfacine. Clin Auton Res 2024; 34:191-201. [PMID: 38064009 DOI: 10.1007/s10286-023-01004-1] [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: 09/05/2023] [Accepted: 11/15/2023] [Indexed: 03/17/2024]
Abstract
PURPOSE Guanfacine is an α2A-adrenergic receptor agonist, FDA-approved to treat attention-deficit hyperactivity disorder and high blood pressure, typically as an extended-release formulation up to 7 mg/day. In our dysautonomia clinic, we observed that off-label use of short-acting guanfacine at 1 mg/day facilitated symptom relief in two families with multiple members presenting with severe generalized anxiety. We also noted anecdotal improvements in associated dysautonomia symptoms such as hyperhidrosis, cognitive impairment, and palpitations. We postulated that a genetic deficit existed in these patients that might augment guanfacine susceptibility. METHODS We used whole-exome sequencing to identify mutations in patients with shared generalized anxiety and dysautonomia symptoms. Guanfacine-induced changes in the function of voltage-gated Na+ channels were investigated using voltage-clamp electrophysiology. RESULTS Whole-exome sequencing uncovered the p.I739V mutation in SCN9A in the proband of two nonrelated families. Moreover, guanfacine inhibited ionic currents evoked by wild-type and mutant NaV1.7 encoded by SCN9A, as well as other NaV channel subtypes to a varying degree. CONCLUSION Our study provides further evidence for a possible pathophysiological role of NaV1.7 in anxiety and dysautonomia. Combined with off-target effects on NaV channel function, daily administration of 1 mg short-acting guanfacine may be sufficient to normalize NaV channel mutation-induced changes in sympathetic activity, perhaps aided by partial inhibition of NaV1.7 or other channel subtypes. In a broader context, expanding genetic and functional data about ion channel aberrations may enable the prospect of stratifying patients in which mutation-induced increased sympathetic tone normalization by guanfacine can support treatment strategies for anxiety and dysautonomia symptoms.
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Affiliation(s)
- Rita de Cássia Collaço
- Molecular Physiology and Neurophysics Group, Department of Basic and Applied Medical Sciences, University of Ghent, Ghent, Belgium
| | - Maxime Lammens
- Molecular Physiology and Neurophysics Group, Department of Basic and Applied Medical Sciences, University of Ghent, Ghent, Belgium
| | - Carley Blevins
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Kristen Rodgers
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Andrei Gurau
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Suguru Yamauchi
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Christine Kim
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Jeannine Forrester
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Edward Liu
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Jinny Ha
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Yuping Mei
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Corrine Boehm
- McKusick-Nathans Department of Genetic Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Elizabeth Wohler
- McKusick-Nathans Department of Genetic Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Nara Sobreira
- McKusick-Nathans Department of Genetic Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Peter C Rowe
- Department of Pediatrics, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - David Valle
- McKusick-Nathans Department of Genetic Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Malcolm V Brock
- Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
| | - Frank Bosmans
- Molecular Physiology and Neurophysics Group, Department of Basic and Applied Medical Sciences, University of Ghent, Ghent, Belgium.
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5
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Ghovanloo MR, Effraim PR, Yuan JH, Schulman BR, Jacobs DS, Dib-Hajj SD, Waxman SG. Nav1.7 P610T mutation in two siblings with persistent ocular pain after corneal axon transection: impaired slow inactivation and hyperexcitable trigeminal neurons. J Neurophysiol 2023; 129:609-618. [PMID: 36722722 PMCID: PMC9988530 DOI: 10.1152/jn.00457.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 01/27/2023] [Accepted: 01/28/2023] [Indexed: 02/02/2023] Open
Abstract
Despite extensive study, the mechanisms underlying pain after axonal injury remain incompletely understood. Pain after corneal refractive surgery provides a model, in humans, of the effect of injury to trigeminal afferent nerves. Axons of trigeminal ganglion neurons that innervate the cornea are transected by laser-assisted in situ keratomileusis (LASIK). Although most patients do not experience postoperative pain, a small subgroup develop persistent ocular pain. We previously carried out genomic analysis and determined that some patients with persistent pain after axotomy of corneal axons during refractive surgery carry mutations in genes that encode the electrogenisome of trigeminal ganglion neurons, the ensemble of ion channels and receptors that regulate excitability within these cells, including SCN9A, which encodes sodium channel Nav1.7, a threshold channel abundantly expressed in sensory neurons that has been implicated in a number of pain-related disorders. Here, we describe the biophysical and electrophysiological profiling of the P610T Nav1.7 mutation found in two male siblings with persistent ocular pain after refractive surgery. Our results indicate that this mutation impairs the slow inactivation of Nav1.7. As expected from this proexcitatory change in channel function, we also demonstrate that this mutation produces increased spontaneous activity in trigeminal ganglion neurons. These findings suggest that this gain-of-function mutation in Nav1.7 may contribute to pain after injury to the axons of trigeminal ganglion neurons.NEW & NOTEWORTHY Mechanisms underlying pain after axonal injury remain elusive. A small subgroup of patients experience pain after corneal refractive surgery, providing a human pain model after well-defined injury to axons. Here we analyze a mutation (P610T) in Nav1.7, a threshold sodium channel expressed in nociceptors, found in two siblings with persistent ocular pain after refractive surgery. We show that it impairs channel slow inactivation, thereby triggering inappropriate repetitive activity in trigeminal ganglion axons that signal eye pain.
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Affiliation(s)
- Mohammad-Reza Ghovanloo
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut, United States
- Center for Neuroscience and Regeneration Research, Yale University, West Haven, Connecticut, United States
- Neuro-Rehabilitation Research Center, Department of Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut, United States
| | - Philip R Effraim
- Center for Neuroscience and Regeneration Research, Yale University, West Haven, Connecticut, United States
- Neuro-Rehabilitation Research Center, Department of Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut, United States
- Department of Anesthesiology, Yale University School of Medicine, New Haven, Connecticut, United States
| | - Jun-Hui Yuan
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut, United States
- Center for Neuroscience and Regeneration Research, Yale University, West Haven, Connecticut, United States
- Neuro-Rehabilitation Research Center, Department of Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut, United States
| | - Betsy R Schulman
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut, United States
- Center for Neuroscience and Regeneration Research, Yale University, West Haven, Connecticut, United States
- Neuro-Rehabilitation Research Center, Department of Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut, United States
| | - Deborah S Jacobs
- Cornea and Refractive Surgery Service, Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, United States
| | - Sulayman D Dib-Hajj
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut, United States
- Center for Neuroscience and Regeneration Research, Yale University, West Haven, Connecticut, United States
- Neuro-Rehabilitation Research Center, Department of Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut, United States
| | - Stephen G Waxman
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut, United States
- Center for Neuroscience and Regeneration Research, Yale University, West Haven, Connecticut, United States
- Neuro-Rehabilitation Research Center, Department of Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut, United States
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6
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Sopacua M, Hoeijmakers JGJ, van der Kooi AJ, Merkies ISJ, Faber CG. Pain triangle phenomenon in possible association with
SCN9A
: A case report. Mol Genet Genomic Med 2022; 10:e2026. [PMID: 36114697 PMCID: PMC9544215 DOI: 10.1002/mgg3.2026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 05/04/2022] [Accepted: 07/19/2022] [Indexed: 11/12/2022] Open
Abstract
Background Voltage‐gated sodium channels are essential for the generation and conduction of electrical impulses in excitable cells. Sodium channel Nav1.7, encoded by the SCN9A‐gene, has been of special interest in the last decades because missense gain‐of‐function mutations have been linked to a spectrum of neuropathic pain conditions, including inherited erythermalgia (IEM), paroxysmal extreme pain disorder (PEPD), and small fiber neuropathy (SFN). Methods In this case report, we present a 61‐year‐old woman who was referred to our tertiary referral center in a standard day care setting with suspicion of SFN. We performed additional investigations: skin biopsy to determine the intra‐epidermal nerve fiber density (IENFD), quantitative sensory testing (QST), and blood examination (including DNA analysis) for possible underlying conditions. Results The patient showed a clinical picture that fulfilled the criteria of IEM, PEPD, and SFN. DNA analysis revealed the heterozygous variant c.554G > A in the SCN9A‐gene (OMIM 603415). This variant has already been described in all three human pain conditions separately, but never in one patient having symptoms of all three conditions. Because its pathogenicity has never been functionally confirmed, the variant is classified as a variance of unknown significance (VUS)/risk factor. This suggests that another genetic and/or environmental substrate plays a role in the development of neuropathic conditions like described. Conclusion We have described this as the SCN9A‐pain triangle phenomenon. Treatment should focus on pain management, genetic counseling, and improving/maintaining quality of life by treating symptoms and, if indicated, starting a rehabilitation program.
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Affiliation(s)
- Maurice Sopacua
- Department of Neurology, School of Mental Health and Neuroscience Maastricht University Medical Center+ Maastricht The Netherlands
- Department of Rehabilitation Medicine Libra Revalidatie & Audiologie Eindhoven The Netherlands
| | - Janneke G. J. Hoeijmakers
- 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 Curaçao Medical Center Willemstad Curaçao
| | - Catharina G. Faber
- Department of Neurology, School of Mental Health and Neuroscience Maastricht University Medical Center+ Maastricht The Netherlands
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Li S, Ding M, Wu Y, Xue S, Ji Y, Zhang P, Zhang Z, Cao Z, Zhang F. Histamine Sensitization of the Voltage-Gated Sodium Channel Nav1.7 Contributes to Histaminergic Itch in Mice. ACS Chem Neurosci 2022; 13:700-710. [PMID: 35157443 DOI: 10.1021/acschemneuro.2c00012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Itch, a common clinical symptom of many skin diseases, severely impairs the life quality of patients. Nav1.7, a subtype of voltage-gated sodium channels mainly expressed in primary sensory neurons, is responsible for the amplification of threshold currents that trigger action potential (AP) generation. Gain-of-function mutation of Nav1.7 leads to paroxysmal itch, while pharmacological inhibition of Nav1.7 alleviates histamine-dependent itch. However, the crosstalk between histamine and Nav1.7 that leads to itch is unclear. In the present study, we demonstrated that in the dorsal root ganglion (DRG) neurons from histamine-dependent itch model mice induced by compound 48/80, tetrodotoxin-sensitive (TTX-S) but not TTX-resistant Na+ currents were activated at more hyperpolarized membrane potentials compared to those on DRG neurons from vehicle-treated mice. Meanwhile, bath application of histamine shifted the activation voltages of TTX-S Na+ currents to the hyperpolarized direction, increased the AP frequency, and reduced the current threshold required to elicit APs. Further mechanistic studies demonstrated that selective activation of H1 but not H2 and H4 receptors mimicked histamine effect on TTX-S Na+ channels in DRG neurons. The protein kinase C (PKC) inhibitor GO 8963, but not the PKA inhibitor H89, normalized histamine-sensitized TTX-S Na+ channels. We also demonstrated that histamine shifted the activation voltages of Na+ currents to the hyperpolarized direction in Chinese hamster ovary (CHO) cells expressing Nav1.7. Importantly, selective inhibition of Nav1.7 by PF-05089771 significantly relieved the scratching frequency in a histamine-dependent itch model induced by compound 48/80. Taken together, these data suggest that activation of H1 receptors by histamine sensitizes Nav1.7 channels through the PKC pathway in DRG neurons that contributes to histamine-dependent itch.
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Affiliation(s)
- Shaoheng Li
- State Key Laboratory of Natural Medicines and Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Development, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Meihuizi Ding
- State Key Laboratory of Natural Medicines and Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Development, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Ying Wu
- State Key Laboratory of Natural Medicines and Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Development, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Shuwen Xue
- State Key Laboratory of Natural Medicines and Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Development, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Yunyun Ji
- State Key Laboratory of Natural Medicines and Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Development, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Pinhui Zhang
- State Key Laboratory of Natural Medicines and Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Development, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Zhuang Zhang
- State Key Laboratory of Natural Medicines and Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Development, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Zhengyu Cao
- State Key Laboratory of Natural Medicines and Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Development, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Fan Zhang
- State Key Laboratory of Natural Medicines and Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Development, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
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8
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Le Cann K, Meents JE, Sudha Bhagavath Eswaran V, Dohrn MF, Bott R, Maier A, Bialer M, Hautvast P, Erickson A, Rolke R, Rothermel M, Körner J, Kurth I, Lampert A. Assessing the impact of pain-linked Nav1.7 variants: An example of two variants with no biophysical effect. Channels (Austin) 2021; 15:208-228. [PMID: 33487118 PMCID: PMC7833769 DOI: 10.1080/19336950.2020.1870087] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 12/23/2020] [Accepted: 12/23/2020] [Indexed: 11/30/2022] Open
Abstract
Mutations in the voltage-gated sodium channel Nav1.7 are linked to human pain. The Nav1.7/N1245S variant was described before in several patients suffering from primary erythromelalgia and/or olfactory hypersensitivity. We have identified this variant in a pain patient and a patient suffering from severe and life-threatening orthostatic hypotension. In addition, we report a female patient suffering from muscle pain and carrying the Nav1.7/E1139K variant. We tested both Nav1.7 variants by whole-cell voltage-clamp recordings in HEK293 cells, revealing a slightly enhanced current density for the N1245S variant when co-expressed with the β1 subunit. This effect was counteracted by an enhanced slow inactivation. Both variants showed similar voltage dependence of activation and steady-state fast inactivation, as well as kinetics of fast inactivation, deactivation, and use-dependency compared to WT Nav1.7. Finally, homology modeling revealed that the N1245S substitution results in different intramolecular interaction partners. Taken together, these experiments do not point to a clear pathogenic effect of either the N1245S or E1139K variant and suggest they may not be solely responsible for the patients' pain symptoms. As discussed previously for other variants, investigations in heterologous expression systems may not sufficiently mimic the pathophysiological situation in pain patients, and single nucleotide variants in other genes or modulatory proteins are necessary for these specific variants to show their effect. Our findings stress that biophysical investigations of ion channel mutations need to be evaluated with care and should preferably be supplemented with studies investigating the mutations in their context, ideally in human sensory neurons.
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Affiliation(s)
- Kim Le Cann
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Jannis E. Meents
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
| | | | - Maike F. Dohrn
- Department of Neurology, Medical Faculty, RWTH Aachen University Hospital, Aachen, Germany
| | - Raya Bott
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Andrea Maier
- Department of Neurology, Medical Faculty, RWTH Aachen University Hospital, Aachen, Germany
| | - Martin Bialer
- Division of Clinical Metabolism of Medical Genetics and Human Genomics at Northwell Health System, New-York, United States
| | - Petra Hautvast
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Andelain Erickson
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
| | - Roman Rolke
- Department for Palliative Care, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Markus Rothermel
- Department of Chemosensation, AG Neuromodulation, Institute for Biology II, RWTH Aachen University, Aachen, 52074, Germany
| | - Jannis Körner
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
- Department of Anaesthesiology, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Ingo Kurth
- Institute of Human Genetics, Medical Faculty, RWTH Aachen University Hospital, Aachen, Germany
| | - Angelika Lampert
- Institute of Physiology, RWTH Aachen University Hospital, Aachen, Germany
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9
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Ganguly S, Thompson CH, George AL. Enhanced slow inactivation contributes to dysfunction of a recurrent SCN2A mutation associated with developmental and epileptic encephalopathy. J Physiol 2021; 599:4375-4388. [PMID: 34287911 PMCID: PMC8446326 DOI: 10.1113/jp281834] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 07/16/2021] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS The recurrent SCN2A mutation R853Q is associated with developmental and epileptic encephalopathy with typical onset after the first months of life. Heterologously expressed R853Q channels exhibit an overall loss-of-function as a result of multiple defects in time- and voltage-dependent channel properties. A previously unrecognized enhancement of slow inactivation is conferred by the R853Q mutation and is a major driver of loss-of-function. Enhanced slow inactivation is potentiated in the canonical splice isoform of the channel and this may explain the later onset of symptoms associated with R853Q. ABSTRACT Mutations in voltage gated sodium (NaV ) channel genes, including SCN2A (encoding NaV 1.2), are associated with diverse neurodevelopmental disorders with or without epilepsy that present clinically with varying severity, age-of-onset and pharmacoresponsiveness. We examined the functional properties of the most recurrent SCN2A mutation (R853Q) to determine whether developmentally-regulated alternative splicing impacts dysfunction severity and to investigate effects of the mutation on slow inactivation. We engineered the R853Q mutation into neonatal and adult NaV 1.2 splice isoforms. Channel constructs were heterologously co-expressed in HEK293T cells with human β1 and β2 subunits. Whole-cell patch clamp recording was used to compare time- and voltage-dependent properties of mutant and wild-type channels. The R853Q mutation exhibits an overall loss-of-function attributed to multiple functional defects including a previously undiscovered enhancement of slow inactivation. The mutation exhibited altered voltage dependence of activation and inactivation, slower recovery from inactivation and decreased channel availability during high-frequency depolarizations. More notable were effects on slow inactivation, including a 10-fold slower rate of recovery from slow inactivation exhibited by mutant channels. The impairments in fast inactivation properties were more severe in the neonatal splice isoform, whereas slow inactivation was more pronounced in the splice isoform of the channel expressed predominantly in later childhood. Enhanced later-onset slow inactivation may be a primary driver of the later onset of neurological features associated with this mutation.
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Affiliation(s)
- Surobhi Ganguly
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL USA
| | - Christopher H. Thompson
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL USA
| | - Alfred L. George
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL USA
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10
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Heinrichs B, Liu B, Zhang J, Meents JE, Le K, Erickson A, Hautvast P, Zhu X, Li N, Liu Y, Spehr M, Habel U, Rothermel M, Namer B, Zhang X, Lampert A, Duan G. The Potential Effect of Na v 1.8 in Autism Spectrum Disorder: Evidence From a Congenital Case With Compound Heterozygous SCN10A Mutations. Front Mol Neurosci 2021; 14:709228. [PMID: 34385907 PMCID: PMC8354588 DOI: 10.3389/fnmol.2021.709228] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 07/07/2021] [Indexed: 12/17/2022] Open
Abstract
Apart from the most prominent symptoms in Autism spectrum disorder (ASD), namely deficits in social interaction, communication and repetitive behavior, patients often show abnormal sensory reactivity to environmental stimuli. Especially potentially painful stimuli are reported to be experienced in a different way compared to healthy persons. In our present study, we identified an ASD patient carrying compound heterozygous mutations in the voltage-gated sodium channel (VGSC) Na v 1.8, which is preferentially expressed in sensory neurons. We expressed both mutations, p.I1511M and p.R512∗, in a heterologous expression system and investigated their biophysical properties using patch-clamp recordings. The results of these experiments reveal that the p.R512∗ mutation renders the channel non-functional, while the p.I1511M mutation showed only minor effects on the channel's function. Behavioral experiments in a Na v 1.8 loss-of-function mouse model additionally revealed that Na v 1.8 may play a role in autism-like symptomatology. Our results present Na v 1.8 as a protein potentially involved in ASD pathophysiology and may therefore offer new insights into the genetic basis of this disease.
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Affiliation(s)
- Björn Heinrichs
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Baowen Liu
- Department of Anesthesiology, The Second Affiliated Hospital, Chongqing Medical University, Chongqing, China
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jin Zhang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jannis E. Meents
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Kim Le
- Department of Chemosensation, AG Neuromodulation, Institute for Biology II, RWTH Aachen University, Aachen, Germany
| | - Andelain Erickson
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Petra Hautvast
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Xiwen Zhu
- Department of Anesthesiology, The Second Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - Ningbo Li
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yi Liu
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Marc Spehr
- Department of Chemosensation, Institute for Biology II, RWTH Aachen University, Aachen, Germany
| | - Ute Habel
- Department of Psychiatry, Psychotherapy and Psychosomatics, Uniklinik RWTH Aachen University, Aachen, Germany
- JARA-BRAIN Institute Brain Structure-Function Relationships: Decoding the Human Brain at Systemic Levels, Forschungszentrum Jülich GmbH and RWTH Aachen University, Aachen, Germany
| | - Markus Rothermel
- Institute for Physiology and Cell Biology, University of Veterinary Medicine, Foundation, Hanover, Germany
| | - Barbara Namer
- Research Group Neurosciences of the Interdisciplinary Center for Clinical Research (IZKF), Faculty of Medicine, RWTH Aachen University, Aachen, Germany
| | - Xianwei Zhang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Angelika Lampert
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Guangyou Duan
- Department of Anesthesiology, The Second Affiliated Hospital, Chongqing Medical University, Chongqing, China
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11
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Abstract
PURPOSE OF REVIEW This article provides a summary of the autonomic neuropathies, including neuropathies associated with diabetes mellitus, neuropathies due to amyloid deposition, immune-mediated autonomic neuropathies (including those associated with a paraneoplastic syndrome), inherited autonomic neuropathies, and toxic autonomic neuropathies. The presenting features, diagnostic investigations, and natural history of these neuropathies are discussed. RECENT FINDINGS Recent findings in autonomic peripheral neuropathy include data on the epidemiology and atypical presentations of diabetic autonomic neuropathy, treatment-induced neuropathy of diabetes mellitus, the presentation of immune-mediated neuropathies, and advances in hereditary neuropathy associated with amyloidosis and other hereditary neuropathies. SUMMARY Knowledge and recognition of the clinical features of the autonomic neuropathies, combined with appropriate laboratory and electrophysiologic testing, will facilitate accurate diagnosis and management.
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12
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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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13
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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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14
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Alsaloum M, Estacion M, Almomani R, Gerrits MM, Bönhof GJ, Ziegler D, Malik R, Ferdousi M, Lauria G, Merkies IS, Faber CG, Dib-Hajj S, Waxman SG. A gain-of-function sodium channel β2-subunit mutation in painful diabetic neuropathy. Mol Pain 2020; 15:1744806919849802. [PMID: 31041876 PMCID: PMC6510061 DOI: 10.1177/1744806919849802] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Diabetes mellitus is a global challenge with many diverse health sequelae, of which diabetic peripheral neuropathy is one of the most common. A substantial number of patients with diabetic peripheral neuropathy develop chronic pain, but the genetic and epigenetic factors that predispose diabetic peripheral neuropathy patients to develop neuropathic pain are poorly understood. Recent targeted genetic studies have identified mutations in α-subunits of voltage-gated sodium channels (Navs) in patients with painful diabetic peripheral neuropathy. Mutations in proteins that regulate trafficking or functional properties of Navs could expand the spectrum of patients with Nav-related peripheral neuropathies. The auxiliary sodium channel β-subunits (β1–4) have been reported to increase current density, alter inactivation kinetics, and modulate subcellular localization of Nav. Mutations in β-subunits have been associated with several diseases, including epilepsy, cancer, and diseases of the cardiac conducting system. However, mutations in β-subunits have never been shown previously to contribute to neuropathic pain. We report here a patient with painful diabetic peripheral neuropathy and negative genetic screening for mutations in SCN9A, SCN10A, and SCN11A—genes encoding sodium channel α-subunit that have been previously linked to the development of neuropathic pain. Genetic analysis revealed an aspartic acid to asparagine mutation, D109N, in the β2-subunit. Functional analysis using current-clamp revealed that the β2-D109N rendered dorsal root ganglion neurons hyperexcitable, especially in response to repetitive stimulation. Underlying the hyperexcitability induced by the β2-subunit mutation, as evidenced by voltage-clamp analysis, we found a depolarizing shift in the voltage dependence of Nav1.7 fast inactivation and reduced use-dependent inhibition of the Nav1.7 channel.
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Affiliation(s)
- Matthew Alsaloum
- 1 Department of Neurology, Yale University School of Medicine, New Haven, CT, USA.,2 Center for Neuroscience and Regeneration Research, Veterans Affairs Medical Center, West Haven, CT, USA.,3 Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT, USA
| | - Mark Estacion
- 1 Department of Neurology, Yale University School of Medicine, New Haven, CT, USA.,2 Center for Neuroscience and Regeneration Research, Veterans Affairs Medical Center, West Haven, CT, USA
| | - Rowida Almomani
- 4 Department of Clinical Genomics, University Medical Center Maastricht, Maastricht, the Netherlands.,5 Department of Medical Laboratory Sciences, Jordan University of Science and Technology, Irbid, Jordan
| | - Monique M Gerrits
- 4 Department of Clinical Genomics, University Medical Center Maastricht, Maastricht, the Netherlands.,6 Department of Neurology, University Medical Centre Maastricht, Maastricht, the Netherlands
| | - Gidon J Bönhof
- 7 Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University, Düsseldorf, Germany
| | - Dan Ziegler
- 7 Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University, Düsseldorf, Germany.,1 8German Center for Diabetes Research, München-Neuherberg, Germany.,9 Division of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Rayaz Malik
- 10 Weill Cornell Medicine-Qatar, Doha, Qatar.,11 Division of Diabetes, Endocrinology and Gastroenterology, Institute of Human Development, University of Manchester, Manchester, UK
| | - Maryam Ferdousi
- 11 Division of Diabetes, Endocrinology and Gastroenterology, Institute of Human Development, University of Manchester, Manchester, UK
| | - Giuseppe Lauria
- 12 Neuroalgology Unit, IRCCS Foundation "Carlo Besta" Neurological Institute, Milan, Italy.,13 Department of Biomedical and Clinical Sciences "Luigi Sacco," University of Milan, Milan, Italy
| | - Ingemar Sj Merkies
- 6 Department of Neurology, University Medical Centre Maastricht, Maastricht, the Netherlands.,14 Department of Neurology, St. Elisabeth Hospital, Willemstad, Curaçao
| | - Catharina G Faber
- 6 Department of Neurology, University Medical Centre Maastricht, Maastricht, the Netherlands
| | - Sulayman Dib-Hajj
- 1 Department of Neurology, Yale University School of Medicine, New Haven, CT, USA.,2 Center for Neuroscience and Regeneration Research, Veterans Affairs Medical Center, West Haven, CT, USA
| | - Stephen G Waxman
- 1 Department of Neurology, Yale University School of Medicine, New Haven, CT, USA.,2 Center for Neuroscience and Regeneration Research, Veterans Affairs Medical Center, West Haven, CT, USA
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15
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Ghasemi M, Rajabally YA. Small fiber neuropathy in unexpected clinical settings: a review. Muscle Nerve 2020; 62:167-175. [PMID: 31943276 DOI: 10.1002/mus.26808] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 01/07/2020] [Accepted: 01/11/2020] [Indexed: 12/12/2022]
Abstract
Small fiber neuropathy (SFN) is being recognized with increasing frequency in neuromuscular practice due to improved diagnostic techniques. Although there are some common etiologies, up to one-third of cases are considered idiopathic. In recent years, several disorders have unexpectedly been reported in association with SFN, on clinical grounds and complementary investigations, including quantitative sensory testing, intraepidermal nerve fiber density and confocal corneal microscopy. Knowledge of these disorders is important in clinical practice as increased awareness enables prompt diagnosis of SFN in these settings and early optimal therapeutic management of affected patients. Furthermore, these new developments may lead to a better understanding of the pathophysiologic mechanisms underlying SFN in these different disorders as well as, in some cases, an expanded spectrum of affected organs and systems. This article reviews these reported associations, their possible pathophysiologic bases, and the potential resulting management implications.
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Affiliation(s)
- Majid Ghasemi
- Regional Neuromuscular Service, University Hospitals Birmingham, Birmingham, United Kingdom.,Department of Neurology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Yusuf A Rajabally
- Regional Neuromuscular Service, University Hospitals Birmingham, Birmingham, United Kingdom.,Aston Medical School, Aston University, Birmingham, United Kingdom
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16
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Lee SI, Hoeijmakers JGJ, Faber CG, Merkies ISJ, Lauria G, Waxman SG. The small fiber neuropathy NaV1.7 I228M mutation: impaired neurite integrity via bioenergetic and mitotoxic mechanisms, and protection by dexpramipexole. J Neurophysiol 2020; 123:645-657. [DOI: 10.1152/jn.00360.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Gain-of-function variants in voltage-gated sodium channel NaV1.7 that increase firing frequency and spontaneous firing of dorsal root ganglion (DRG) neurons have recently been identified in 5–10% of patients with idiopathic small fiber neuropathy (I-SFN). Our previous in vitro observations suggest that enhanced sodium channel activity can contribute to a decrease in length of peripheral sensory axons. We have hypothesized that sustained sodium influx due to the expression of SFN-associated sodium channel variants may trigger an energetic deficit in neurons that contributes to degeneration and loss of nerve fibers in SFN. Using an ATP FRET biosensor, we now demonstrate reduced steady-state levels of ATP and markedly faster ATP decay in response to membrane depolarization in cultured DRG neurons expressing an SFN-associated variant NaV1.7, I228M, compared with wild-type neurons. We also observed that I228M neurons show a significant reduction in mitochondrial density and size, indicating dysfunctional mitochondria and a reduced bioenergetic capacity. Finally, we report that exposure to dexpramipexole, a drug that improves mitochondrial energy metabolism, increases the neurite length of I228M-expressing neurons. Our data suggest that expression of gain-of-function variants of NaV1.7 can damage mitochondria and compromise cellular capacity for ATP production. The resulting bioenergetic crisis can consequently contribute to loss of axons in SFN. We suggest that, in addition to interventions that reduce ionic disturbance caused by mutant NaV1.7 channels, an alternative therapeutic strategy might target the bioenergetic burden and mitochondrial damage that occur in SFN associated with NaV1.7 gain-of-function mutations. NEW & NOTEWORTHY Sodium channel NaV1.7 mutations that increase dorsal root ganglion (DRG) neuron excitability have been identified in small fiber neuropathy (SFN). We demonstrate reduced steady-state ATP levels, faster depolarization-evoked ATP decay, and reduced mitochondrial density and size in cultured DRG neurons expressing SFN-associated variant NaV1.7 I228M. Dexpramipexole, which improves mitochondrial energy metabolism, has a protective effect. Because gain-of-function NaV1.7 variants can compromise bioenergetics, therapeutic strategies that target bioenergetic burden and mitochondrial damage merit study in SFN.
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Affiliation(s)
- Seong-il Lee
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut
- Center for Neuroscience and Regeneration Research, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Janneke G. J. Hoeijmakers
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Center+, 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, Curaçao Medical Center, Willemstad, Curaçao
| | - Giuseppe Lauria
- Neuroalgology Unit, Foundazione IRCCS Istituto Neurologico “Carlo Besta,” Milan, Italy
- Department of Biomedical and Clinical Sciences “Luigi Sacco,” University of Milan, Milan, Italy
| | - Stephen G. Waxman
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut
- Center for Neuroscience and Regeneration Research, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
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17
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de Greef BTA, Hoeijmakers JGJ, Geerts M, Oakes M, Church TJE, Waxman SG, Dib-Hajj SD, Faber CG, Merkies ISJ. Lacosamide in patients with Nav1.7 mutations-related small fibre neuropathy: a randomized controlled trial. Brain 2019; 142:263-275. [PMID: 30649227 DOI: 10.1093/brain/awy329] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Accepted: 11/02/2018] [Indexed: 11/14/2022] Open
Abstract
Symptomatic treatment of neuropathic pain in small fibre neuropathy is often disappointing. The finding of voltage-gated sodium channel mutations in small fibre neuropathy (with mutations in SCN9A, encoding for Nav1.7) being most frequently reported suggest a specific target for therapy. The anticonvulsant lacosamide acts on Nav1.3, Nav1.7, and Nav1.8. The aim of this study was to evaluate the efficacy, safety, and tolerability of lacosamide as a potential treatment for pain in Nav1.7-related small fibre neuropathy. The Lacosamide-Efficacy-'N'-Safety in SFN (LENSS) was a randomized, placebo-controlled, double-blind, crossover-design study. Subjects were recruited in the Netherlands between November 2014 and July 2016. Patients with Nav1.7-related small fibre neuropathy were randomized to start with lacosamide followed by placebo or vice versa. In both 8-week treatment phases, patients received 200 mg two times a day (BID), preceded by a titration period, and ended by a tapering period. The primary outcome was efficacy, defined as the proportion of patients with 1-point average pain score reduction compared to baseline using the Pain Intensity Numerical Rating Scale. The trial is registered with ClinicalTrials.gov, number NCT01911975. Twenty-four subjects received lacosamide, and 23 received placebo. In 58.3% of patients receiving lacosamide, mean average pain decreased by at least 1 point, compared to 21.7% in the placebo group [sensitivity analyses, odds ratio 5.65 (95% confidence interval: 1.83-17.41); P = 0.0045]. In the lacosamide group, 33.3% reported that their general condition improved versus 4.3% in the placebo group (P-value = 0.0156). Additionally, a significant decrease in daily sleep interference, and in surface pain intensity was demonstrated. No significant changes in quality of life or autonomic symptoms were found. Lacosamide was well tolerated and safe in use. This study shows that lacosamide has a significant effect on pain, general wellbeing, and sleep quality. Lacosamide was well tolerated and safe, suggesting that it can be used for pain treatment in Nav1.7-related small fibre neuropathy.
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Affiliation(s)
- Bianca T A de Greef
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Center+, 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
| | - Mike Oakes
- ParamStat Limited, University of Sussex, Fairlight, East Sussex, UK
| | | | - Stephen G Waxman
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut, USA.,Center for Neuroscience and Regeneration Research, Veterans Affairs Medical Center, West Haven, Connecticut, USA
| | - Sulayman D Dib-Hajj
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut, USA.,Center for Neuroscience and Regeneration Research, Veterans Affairs Medical Center, West Haven, Connecticut, USA
| | - 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
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18
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µ-TRTX-Ca1a: a novel neurotoxin from Cyriopagopus albostriatus with analgesic effects. Acta Pharmacol Sin 2019; 40:859-866. [PMID: 30382183 DOI: 10.1038/s41401-018-0181-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 09/30/2018] [Indexed: 12/16/2022] Open
Abstract
Human genetic and pharmacological studies have demonstrated that voltage-gated sodium channels (VGSCs) are promising therapeutic targets for the treatment of pain. Spider venom contains many toxins that modulate the activity of VGSCs. To date, only 0.01% of such spider toxins has been explored, and thus there is a great potential for discovery of novel VGSC modulators as useful pharmacological tools or potential therapeutics. In the current study, we identified a novel peptide, µ-TRTX-Ca1a (Ca1a), in the venom of the tarantula Cyriopagopus albostriatus. This peptide consisted of 38 residues, including 6 cysteines, i.e. IFECSISCEIEKEGNGKKCKPKKCKGGWKCKFNICVKV. In HEK293T or ND7/23 cells expressing mammalian VGSCs, this peptide exhibited the strongest inhibitory activity on Nav1.7 (IC50 378 nM), followed by Nav1.6 (IC50 547 nM), Nav1.2 (IC50 728 nM), Nav1.3 (IC50 2.2 µM) and Nav1.4 (IC50 3.2 µM), and produced negligible inhibitory effect on Nav1.5, Nav1.8, and Nav1.9, even at high concentrations of up to 10 µM. Furthermore, this peptide did not significantly affect the activation and inactivation of Nav1.7. Using site-directed mutagenesis of Nav1.7 and Nav1.4, we revealed that its binding site was localized to the DIIS3-S4 linker region involving the D816 and E818 residues. In three different mouse models of pain, pretreatment with Cala (100, 200, 500 µg/kg) dose-dependently suppressed the nociceptive responses induced by formalin, acetic acid or heat. These results suggest that Ca1a is a novel neurotoxin against VGSCs and has a potential to be developed as a novel analgesic.
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19
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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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20
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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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21
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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: 42] [Impact Index Per Article: 8.4] [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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22
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Maatuf Y, Geron M, Priel A. The Role of Toxins in the Pursuit for Novel Analgesics. Toxins (Basel) 2019; 11:toxins11020131. [PMID: 30813430 PMCID: PMC6409898 DOI: 10.3390/toxins11020131] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 02/17/2019] [Accepted: 02/20/2019] [Indexed: 12/19/2022] Open
Abstract
Chronic pain is a major medical issue which reduces the quality of life of millions and inflicts a significant burden on health authorities worldwide. Currently, management of chronic pain includes first-line pharmacological therapies that are inadequately effective, as in just a portion of patients pain relief is obtained. Furthermore, most analgesics in use produce severe or intolerable adverse effects that impose dose restrictions and reduce compliance. As the majority of analgesic agents act on the central nervous system (CNS), it is possible that blocking pain at its source by targeting nociceptors would prove more efficient with minimal CNS-related side effects. The development of such analgesics requires the identification of appropriate molecular targets and thorough understanding of their structural and functional features. To this end, plant and animal toxins can be employed as they affect ion channels with high potency and selectivity. Moreover, elucidation of the toxin-bound ion channel structure could generate pharmacophores for rational drug design while favorable safety and analgesic profiles could highlight toxins as leads or even as valuable therapeutic compounds themselves. Here, we discuss the use of plant and animal toxins in the characterization of peripherally expressed ion channels which are implicated in pain.
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Affiliation(s)
- Yossi Maatuf
- The Institute for Drug Research (IDR), School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112001, Israel.
| | - Matan Geron
- The Institute for Drug Research (IDR), School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112001, Israel.
| | - Avi Priel
- The Institute for Drug Research (IDR), School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112001, Israel.
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23
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Abstract
PURPOSE OF REVIEW This article provides a conceptual framework for the evaluation of patients with suspected polyneuropathy to enhance the clinician's ability to localize and confirm peripheral nervous system pathology and, when possible, identify an etiologic diagnosis through use of rational clinical and judicious testing strategies. RECENT FINDINGS Although these strategies are largely time-honored, recent insights pertaining to the pathophysiology of certain immune-mediated neuropathies and to evolving genetic testing strategies may modify the way that select causes of neuropathy are conceptualized, evaluated, and managed. SUMMARY The strategies suggested in this article are intended to facilitate accurate bedside diagnosis in patients with suspected polyneuropathy and allow efficient and judicious use of supplementary testing and application of rational treatment when indicated.
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24
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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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Abstract
Fibromyalgia appears to present in subgroups with regard to biological pain induction, with primarily inflammatory, neuropathic/neurodegenerative, sympathetic, oxidative, nitrosative, or muscular factors and/or central sensitization. Recent research has also discussed glial activation or interrupted dopaminergic neurotransmission, as well as increased skin mast cells and mitochondrial dysfunction. Therapy is difficult, and the treatment options used so far mostly just have the potential to address only one of these aspects. As ambroxol addresses all of them in a single substance and furthermore also reduces visceral hypersensitivity, in fibromyalgia existing as irritable bowel syndrome or chronic bladder pain, it should be systematically investigated for this purpose. Encouraged by first clinical observations of two working groups using topical or oral ambroxol for fibromyalgia treatments, the present paper outlines the scientific argument for this approach by looking at each of the aforementioned aspects of this complex disease and summarizes putative modes of action of ambroxol. Nevertheless, at this point the evidence basis for ambroxol is not strong enough for clinical recommendation.
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Affiliation(s)
- Kai-Uwe Kern
- Institute of Pain Medicine/Pain Practice, Wiesbaden, Germany
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Graceffa RF, Boezio AA, Able J, Altmann S, Berry LM, Boezio C, Butler JR, Chu-Moyer M, Cooke M, DiMauro EF, Dineen TA, Feric Bojic E, Foti RS, Fremeau RT, Guzman-Perez A, Gao H, Gunaydin H, Huang H, Huang L, Ilch C, Jarosh M, Kornecook T, Kreiman CR, La DS, Ligutti J, Milgram BC, Lin MHJ, Marx IE, Nguyen HN, Peterson EA, Rescourio G, Roberts J, Schenkel L, Shimanovich R, Sparling BA, Stellwagen J, Taborn K, Vaida KR, Wang J, Yeoman J, Yu V, Zhu D, Moyer BD, Weiss MM. Sulfonamides as Selective NaV1.7 Inhibitors: Optimizing Potency, Pharmacokinetics, and Metabolic Properties to Obtain Atropisomeric Quinolinone (AM-0466) that Affords Robust in Vivo Activity. J Med Chem 2017; 60:5990-6017. [DOI: 10.1021/acs.jmedchem.6b01850] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
| | | | - Jessica Able
- Department
of Neuroscience, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Thomas Kornecook
- Department
of Neuroscience, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | | | | | - Joseph Ligutti
- Department
of Neuroscience, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Bryan D. Moyer
- Department
of Neuroscience, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
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Helås T, Sagafos D, Kleggetveit I, Quiding H, Jönsson B, Segerdahl M, Zhang Z, Salter H, Schmelz M, Jørum E. Pain thresholds,supra-threshold pain and lidocaine sensitivity in patients with erythromelalgia, including the I848Tmutation in NaV1.7. Eur J Pain 2017; 21:1316-1325. [DOI: 10.1002/ejp.1030] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/10/2017] [Indexed: 11/09/2022]
Affiliation(s)
- T. Helås
- Section of Clinical Neurophysiology, Department of Neurology; Oslo University Hospital - Rikshospitalet; Norway
| | - D. Sagafos
- Section of Clinical Neurophysiology, Department of Neurology; Oslo University Hospital - Rikshospitalet; Norway
| | - I.P. Kleggetveit
- Section of Clinical Neurophysiology, Department of Neurology; Oslo University Hospital - Rikshospitalet; Norway
| | | | | | | | - Z. Zhang
- Astra-Zeneca R&D; Södertälje Sweden
| | - H. Salter
- Astra-Zeneca R&D; Södertälje Sweden
- Department of Clinical Neuroscience; Karolinska Institutet; Solna Sweden
| | - M. Schmelz
- Department of Anesthesiology Mannheim; Heidelberg University; Germany
| | - E. Jørum
- Section of Clinical Neurophysiology, Department of Neurology; Oslo University Hospital - Rikshospitalet; Norway
- Faculty of Medicine, Institute of Clinical Medicine; University of Oslo; Norway
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Tanaka BS, Nguyen PT, Zhou EY, Yang Y, Yarov-Yarovoy V, Dib-Hajj SD, Waxman SG. Gain-of-function mutation of a voltage-gated sodium channel Na V1.7 associated with peripheral pain and impaired limb development. J Biol Chem 2017; 292:9262-9272. [PMID: 28381558 DOI: 10.1074/jbc.m117.778779] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 03/24/2017] [Indexed: 01/20/2023] Open
Abstract
Dominant mutations in voltage-gated sodium channel NaV1.7 cause inherited erythromelalgia, a debilitating pain disorder characterized by severe burning pain and redness of the distal extremities. NaV1.7 is preferentially expressed within peripheral sensory and sympathetic neurons. Here, we describe a novel NaV1.7 mutation in an 11-year-old male with underdevelopment of the limbs, recurrent attacks of burning pain with erythema, and swelling in his feet and hands. Frequency and duration of the episodes gradually increased with age, and relief by cooling became less effective. The patient's sister had short stature and reported similar complaints of erythema and burning pain, but with less intensity. Genetic analysis revealed a novel missense mutation in NaV1.7 (2567G>C; p.Gly856Arg) in both siblings. The G856R mutation, located within the DII/S4-S5 linker of the channel, substitutes a highly conserved non-polar glycine by a positively charged arginine. Voltage-clamp analysis of G856R currents revealed that the mutation hyperpolarized (-11.2 mV) voltage dependence of activation and slowed deactivation but did not affect fast inactivation, compared with wild-type channels. A mutation of Gly-856 to aspartic acid was previously found in a family with limb pain and limb underdevelopment, and its functional assessment showed hyperpolarized activation, depolarized fast inactivation, and increased ramp current. Structural modeling using the Rosetta computational modeling suite provided structural clues to the divergent effects of the substitution of Gly-856 by arginine and aspartic acid. Although the proexcitatory changes in gating properties of G856R contribute to the pathophysiology of inherited erythromelalgia, the link to limb underdevelopment is not well understood.
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Affiliation(s)
- Brian S Tanaka
- From the Department of Neurology.,the Center for Neuroscience & Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510.,the Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Phuong T Nguyen
- the Department of Physiology and Membrane Biology and.,the Biophysics Graduate Group, University of California, Davis, California 95616
| | - Eray Yihui Zhou
- the Department of Dermatology, Peking University First Hospital, Beijing 100034, China, and.,the Department of Dermatology, Beijing Tsinghua Changgung Hospital, Tsinghua University, Beijing 102218, China
| | - Yong Yang
- the Department of Dermatology, Peking University First Hospital, Beijing 100034, China, and
| | - Vladimir Yarov-Yarovoy
- the Department of Physiology and Membrane Biology and.,the Biophysics Graduate Group, University of California, Davis, California 95616
| | - Sulayman D Dib-Hajj
- From the Department of Neurology.,the Center for Neuroscience & Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510.,the Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Stephen G Waxman
- From the Department of Neurology, .,the Center for Neuroscience & Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510.,the Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
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Jensen TS. Selective sodium channel blockers in trigeminal neuralgia. Lancet Neurol 2017; 16:255-256. [DOI: 10.1016/s1474-4422(17)30017-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 01/24/2017] [Indexed: 01/19/2023]
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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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Rolyan H, Liu S, Hoeijmakers JG, Faber CG, Merkies IS, Lauria G, Black JA, Waxman SG. A painful neuropathy-associated Nav1.7 mutant leads to time-dependent degeneration of small-diameter axons associated with intracellular Ca2+ dysregulation and decrease in ATP levels. Mol Pain 2016; 12:1744806916674472. [PMID: 27821467 PMCID: PMC5102167 DOI: 10.1177/1744806916674472] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 08/10/2016] [Accepted: 08/16/2016] [Indexed: 11/25/2022] Open
Abstract
Small fiber neuropathy is a painful sensory nervous system disorder characterized by damage to unmyelinated C- and thinly myelinated Aδ- nerve fibers, clinically manifested by burning pain in the distal extremities and dysautonomia. The clinical onset in adulthood suggests a time-dependent process. The mechanisms that underlie nerve fiber injury in small fiber neuropathy are incompletely understood, although roles for energetic stress have been suggested. In the present study, we report time-dependent degeneration of neurites from dorsal root ganglia neurons in culture expressing small fiber neuropathy-associated G856D mutant Nav1.7 channels and demonstrate a time-dependent increase in intracellular calcium levels [Ca2+]i and reactive oxygen species, together with a decrease in ATP levels. Together with a previous clinical report of burning pain in the feet and hands associated with reduced levels of Na+/K+-ATPase in humans with high altitude sickness, the present results link energetic stress and reactive oxygen species production with the development of a painful neuropathy that preferentially affects small-diameter axons.
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Affiliation(s)
- Harshvardhan Rolyan
- Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
- Neuroscience and Regeneration Research Center, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Shujun Liu
- Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
- Neuroscience and Regeneration Research Center, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Janneke Gj Hoeijmakers
- Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Catharina G Faber
- Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Ingemar Sj Merkies
- Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands
- Department of Neurology, St. Elisabeth Hospital, Willemstad, Curaçao
| | - Giuseppe Lauria
- Neuroalgology Unit, IRCCS, Carlo Besta Neurological Institute, Milan, Italy
| | - Joel A Black
- Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
- Neuroscience and Regeneration Research Center, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Stephen G Waxman
- Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
- Neuroscience and Regeneration Research Center, VA Connecticut Healthcare System, West Haven, CT, USA
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Advanced Genetic Testing Comes to the Pain Clinic to Make a Diagnosis of Paroxysmal Extreme Pain Disorder. Case Rep Neurol Med 2016; 2016:9212369. [PMID: 27525141 PMCID: PMC4972908 DOI: 10.1155/2016/9212369] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 06/02/2016] [Accepted: 06/26/2016] [Indexed: 12/22/2022] Open
Abstract
Objective. To describe the use of an advanced genetic testing technique, whole exome sequencing, to diagnose a patient and their family with a SCN9A channelopathy. Setting. Academic tertiary care center. Design. Case report. Case Report. A 61-year-old female with a history of acute facial pain, chronic pain, fibromyalgia, and constipation was found to have a gain of function SCN9A mutation by whole exome sequencing. This mutation resulted in an SCN9A channelopathy that is most consistent with a diagnosis of paroxysmal extreme pain disorder. In addition to the patient being diagnosed, four siblings have a clinical diagnosis of SCN9A channelopathy as they have consistent symptoms and a sister with a known mutation. For treatment, gabapentin was ineffective and carbamazepine was not tolerated. Nontraditional therapies improved symptoms and constipation resolved with pelvic floor retraining with biofeedback. Conclusion. Patients with a personal and family history of chronic pain may benefit from a referral to Medical Genetics. Pelvic floor retraining with biofeedback should be considered for patients with a SCN9A channelopathy and constipation.
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Sodium Channels, Mitochondria, and Axonal Degeneration in Peripheral Neuropathy. Trends Mol Med 2016; 22:377-390. [DOI: 10.1016/j.molmed.2016.03.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 03/21/2016] [Accepted: 03/22/2016] [Indexed: 12/19/2022]
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Differential modulation of Nav1.7 and Nav1.8 channels by antidepressant drugs. Eur J Pharmacol 2015; 764:395-403. [DOI: 10.1016/j.ejphar.2015.06.053] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 06/25/2015] [Accepted: 06/26/2015] [Indexed: 02/03/2023]
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Matson DJ, Hamamoto DT, Bregman H, Cooke M, DiMauro EF, Huang L, Johnson D, Li X, McDermott J, Morgan C, Wilenkin B, Malmberg AB, McDonough SI, Simone DA. Inhibition of Inactive States of Tetrodotoxin-Sensitive Sodium Channels Reduces Spontaneous Firing of C-Fiber Nociceptors and Produces Analgesia in Formalin and Complete Freund's Adjuvant Models of Pain. PLoS One 2015; 10:e0138140. [PMID: 26379236 PMCID: PMC4575030 DOI: 10.1371/journal.pone.0138140] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 08/25/2015] [Indexed: 11/18/2022] Open
Abstract
While genetic evidence shows that the Nav1.7 voltage-gated sodium ion channel is a key regulator of pain, it is unclear exactly how Nav1.7 governs neuronal firing and what biophysical, physiological, and distribution properties of a pharmacological Nav1.7 inhibitor are required to produce analgesia. Here we characterize a series of aminotriazine inhibitors of Nav1.7 in vitro and in rodent models of pain and test the effects of the previously reported "compound 52" aminotriazine inhibitor on the spiking properties of nociceptors in vivo. Multiple aminotriazines, including some with low terminal brain to plasma concentration ratios, showed analgesic efficacy in the formalin model of pain. Effective concentrations were consistent with the in vitro potency as measured on partially-inactivated Nav1.7 but were far below concentrations required to inhibit non-inactivated Nav1.7. Compound 52 also reversed thermal hyperalgesia in the complete Freund's adjuvant (CFA) model of pain. To study neuronal mechanisms, electrophysiological recordings were made in vivo from single nociceptive fibers from the rat tibial nerve one day after CFA injection. Compound 52 reduced the spontaneous firing of C-fiber nociceptors from approximately 0.7 Hz to 0.2 Hz and decreased the number of action potentials evoked by suprathreshold tactile and heat stimuli. It did not, however, appreciably alter the C-fiber thresholds for response to tactile or thermal stimuli. Surprisingly, compound 52 did not affect spontaneous activity or evoked responses of Aδ-fiber nociceptors. Results suggest that inhibition of inactivated states of TTX-S channels, mostly likely Nav1.7, in the peripheral nervous system produces analgesia by regulating the spontaneous discharge of C-fiber nociceptors.
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Affiliation(s)
- David J. Matson
- Department of Neuroscience, Amgen Inc., Cambridge, Massachusetts, United States of America
| | - Darryl T. Hamamoto
- Department of Diagnostics and Biological Sciences, University of Minnesota School of Dentistry, Minneapolis, Minnesota, United States of America
| | - Howard Bregman
- Department of Medicinal Chemistry, Amgen Inc., Cambridge, Massachusetts, United States of America
| | - Melanie Cooke
- Department of Pharmaceutics Research & Development, Amgen Inc., Cambridge, Massachusetts, United States of America
| | - Erin F. DiMauro
- Department of Medicinal Chemistry, Amgen Inc., Cambridge, Massachusetts, United States of America
| | - Liyue Huang
- Department of Pharmacokinetics & Drug Metabolism, Amgen Inc., Cambridge, Massachusetts, United States of America
| | - Danielle Johnson
- Department of Neuroscience, Amgen Inc., Cambridge, Massachusetts, United States of America
| | - Xingwen Li
- Department of Pharmacokinetics & Drug Metabolism, Amgen Inc., Cambridge, Massachusetts, United States of America
| | - Jeff McDermott
- Department of Neuroscience, Amgen Inc., Cambridge, Massachusetts, United States of America
| | - Carrie Morgan
- Department of Pharmaceutics Research & Development, Amgen Inc., Cambridge, Massachusetts, United States of America
| | - Ben Wilenkin
- Department of Neuroscience, Amgen Inc., Cambridge, Massachusetts, United States of America
| | - Annika B. Malmberg
- Department of Neuroscience, Amgen Inc., Cambridge, Massachusetts, United States of America
| | - Stefan I. McDonough
- Department of Neuroscience, Amgen Inc., Cambridge, Massachusetts, United States of America
| | - Donald A. Simone
- Department of Diagnostics and Biological Sciences, University of Minnesota School of Dentistry, Minneapolis, Minnesota, United States of America
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Hoeijmakers JG, Faber CG, Merkies IS, Waxman SG. Painful peripheral neuropathy and sodium channel mutations. Neurosci Lett 2015; 596:51-9. [DOI: 10.1016/j.neulet.2014.12.056] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Revised: 12/22/2014] [Accepted: 12/29/2014] [Indexed: 12/19/2022]
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Schreiber AK, Nones CFM, Reis RC, Chichorro JG, Cunha JM. Diabetic neuropathic pain: Physiopathology and treatment. World J Diabetes 2015; 6:432-444. [PMID: 25897354 PMCID: PMC4398900 DOI: 10.4239/wjd.v6.i3.432] [Citation(s) in RCA: 233] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 11/26/2014] [Accepted: 02/09/2015] [Indexed: 02/05/2023] Open
Abstract
Diabetic neuropathy is a common complication of both type 1 and type 2 diabetes, which affects over 90% of the diabetic patients. Although pain is one of the main symptoms of diabetic neuropathy, its pathophysiological mechanisms are not yet fully known. It is widely accepted that the toxic effects of hyperglycemia play an important role in the development of this complication, but several other hypotheses have been postulated. The management of diabetic neuropathic pain consists basically in excluding other causes of painful peripheral neuropathy, improving glycemic control as a prophylactic therapy and using medications to alleviate pain. First line drugs for pain relief include anticonvulsants, such as pregabalin and gabapentin and antidepressants, especially those that act to inhibit the reuptake of serotonin and noradrenaline. In addition, there is experimental and clinical evidence that opioids can be helpful in pain control, mainly if associated with first line drugs. Other agents, including for topical application, such as capsaicin cream and lidocaine patches, have also been proposed to be useful as adjuvants in the control of diabetic neuropathic pain, but the clinical evidence is insufficient to support their use. In conclusion, a better understanding of the mechanisms underlying diabetic neuropathic pain will contribute to the search of new therapies, but also to the improvement of the guidelines to optimize pain control with the drugs currently available.
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Abstract
Pharmacological, surgical, psychological, and alternative medicine approaches for the treatment of chronic pain, including neuropathic pain, provide only partial relief for most patients, with the efficacy of existing medications often blunted by dose-limiting side effects arising from drug actions on cells outside the pain-signaling axis. The development of more effective treatments for pain--particularly chronic pain states such as neuropathic pain--has been hampered by lack of predictive animal models and biomarkers, variation in pain characteristics between patients or on a day-to-day basis for single patients, patient stratification on the basis of symptoms rather than mechanism, and a high rate of placebo responses. We discuss genetic and genomic approaches to translational pain research. We review examples of the identification and validation of human pain targets through rodent genome-wide association studies (GWAS) and global mRNA expression studies, functional screening in flies and mice, human GWAS and whole-exome sequencing studies, and the targeted candidate gene approach. These and other emerging genetic and genomic strategies are likely to facilitate the development of new, more effective pain therapeutics.
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Affiliation(s)
- 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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41
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Han C, Yang Y, de Greef BTA, Hoeijmakers JGJ, Gerrits MM, Verhamme C, Qu J, Lauria G, Merkies ISJ, Faber CG, Dib-Hajj SD, Waxman SG. The Domain II S4-S5 Linker in Nav1.9: A Missense Mutation Enhances Activation, Impairs Fast Inactivation, and Produces Human Painful Neuropathy. Neuromolecular Med 2015; 17:158-69. [DOI: 10.1007/s12017-015-8347-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 03/09/2015] [Indexed: 10/23/2022]
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p.L1612P, a Novel Voltage-gated Sodium Channel Nav1.7 Mutation Inducing a Cold Sensitive Paroxysmal Extreme Pain Disorder. Anesthesiology 2015; 122:414-23. [DOI: 10.1097/aln.0000000000000476] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Background:
Mutations in the SCN9A gene cause chronic pain and pain insensitivity syndromes. We aimed to study clinical, genetic, and electrophysiological features of paroxysmal extreme pain disorder (PEPD) caused by a novel SCN9A mutation.
Methods:
Description of a 4-generation family suffering from PEPD with clinical, genetic and electrophysiological studies including patch clamp experiments assessing response to drug and temperature.
Results:
The family was clinically comparable to those reported previously with the exception of a favorable effect of cold exposure and a lack of drug efficacy including with carbamazepine, a proposed treatment for PEPD. A novel p.L1612P mutation in the Nav1.7 voltage-gated sodium channel was found in the four affected family members tested. Electrophysiologically the mutation substantially depolarized the steady–state inactivation curve (V1/2 from −61.8 ± 4.5 mV to −30.9 ± 2.2 mV, n = 4 and 7, P < 0.001), significantly increased ramp current (from 1.8% to 3.4%, n = 10 and 12) and shortened recovery from inactivation (from 7.2 ± 5.6 ms to 2.2 ± 1.5 ms, n = 11 and 10). However, there was no persistent current. Cold exposure reduced peak current and prolonged recovery from inactivation in wild-type and mutated channels. Amitriptyline only slightly corrected the steady–state inactivation shift of the mutated channel, which is consistent with the lack of clinical benefit.
Conclusions:
The novel p.L1612P Nav1.7 mutation expands the PEPD spectrum with a unique combination of clinical symptoms and electrophysiological properties. Symptoms are partially responsive to temperature but not to drug therapy. In vitro trials of sodium channel blockers or temperature dependence might help predict treatment efficacy in PEPD.
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Depolarized inactivation overcomes impaired activation to produce DRG neuron hyperexcitability in a Nav1.7 mutation in a patient with distal limb pain. J Neurosci 2015; 34:12328-40. [PMID: 25209274 DOI: 10.1523/jneurosci.2773-14.2014] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Sodium channel Nav1.7, encoded by SCN9A, is expressed in DRG neurons and regulates their excitability. Genetic and functional studies have established a critical contribution of Nav1.7 to human pain disorders. We have now characterized a novel Nav1.7 mutation (R1279P) from a female human subject with distal limb pain, in which depolarized fast inactivation overrides impaired activation to produce hyperexcitability and spontaneous firing in DRG neurons. Whole-cell voltage-clamp recordings in human embryonic kidney (HEK) 293 cells demonstrated that R1279P significantly depolarizes steady-state fast-, slow-, and closed-state inactivation. It accelerates deactivation, decelerates inactivation, and facilitates repriming. The mutation increases ramp currents in response to slow depolarizations. Our voltage-clamp analysis showed that R1279P depolarizes channel activation, a change that was supported by our multistate structural modeling. Because this mutation confers both gain-of-function and loss-of-function attributes on the Nav1.7 channel, we tested the impact of R1279P expression on DRG neuron excitability. Current-clamp studies reveal that R1279P depolarizes resting membrane potential, decreases current threshold, and increases firing frequency of evoked action potentials within small DRG neurons. The populations of spontaneously firing and repetitively firing neurons were increased by expressing R1279P. These observations indicate that the dominant proexcitatory gating changes associated with this mutation, including depolarized steady-state fast-, slow-, and closed-state inactivation, faster repriming, and larger ramp currents, override the depolarizing shift of activation, to produce hyperexcitability and spontaneous firing of nociceptive neurons that underlie pain.
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Saporta MA, Dang V, Volfson D, Zou B, Xie XS, Adebola A, Liem RK, Shy M, Dimos JT. Axonal Charcot-Marie-Tooth disease patient-derived motor neurons demonstrate disease-specific phenotypes including abnormal electrophysiological properties. Exp Neurol 2015; 263:190-9. [PMID: 25448007 PMCID: PMC4262589 DOI: 10.1016/j.expneurol.2014.10.005] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 09/28/2014] [Accepted: 10/10/2014] [Indexed: 01/22/2023]
Abstract
OBJECTIVE Charcot-Marie-Tooth (CMT) disease is a group of inherited peripheral neuropathies associated with mutations or copy number variations in over 70 genes encoding proteins with fundamental roles in the development and function of Schwann cells and peripheral axons. Here, we used iPSC-derived cells to identify common pathophysiological mechanisms in axonal CMT. METHODS iPSC lines from patients with two distinct forms of axonal CMT (CMT2A and CMT2E) were differentiated into spinal cord motor neurons and used to study axonal structure and function and electrophysiological properties in vitro. RESULTS iPSC-derived motor neurons exhibited gene and protein expression, ultrastructural and electrophysiological features of mature primary spinal cord motor neurons. Cytoskeletal abnormalities were found in neurons from a CMT2E (NEFL) patient and corroborated by a mouse model of the same NEFL point mutation. Abnormalities in mitochondrial trafficking were found in neurons derived from this patient, but were only mildly present in neurons from a CMT2A (MFN2) patient. Novel electrophysiological abnormalities, including reduced action potential threshold and abnormal channel current properties were observed in motor neurons derived from both of these patients. INTERPRETATION Human iPSC-derived motor neurons from axonal CMT patients replicated key pathophysiological features observed in other models of MFN2 and NEFL mutations, including abnormal cytoskeletal and mitochondrial dynamics. Electrophysiological abnormalities found in axonal CMT iPSC-derived human motor neurons suggest that these cells are hyperexcitable and have altered sodium and calcium channel kinetics. These findings may provide a new therapeutic target for this group of heterogeneous inherited neuropathies.
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Affiliation(s)
- Mario A Saporta
- Department of Neurology, University of Iowa, USA; iPierian Inc., USA.
| | | | | | | | | | - Adijat Adebola
- Department of Pathology and Cell Biology, Columbia University Medical Center, USA
| | - Ronald K Liem
- Department of Pathology and Cell Biology, Columbia University Medical Center, USA
| | - Michael Shy
- Department of Neurology, University of Iowa, USA
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Wainger BJ, Buttermore ED, Oliveira JT, Mellin C, Lee S, Saber WA, Wang A, Ichida JK, Chiu IM, Barrett L, Huebner EA, Bilgin C, Tsujimoto N, Brenneis C, Kapur K, Rubin LL, Eggan K, Woolf CJ. Modeling pain in vitro using nociceptor neurons reprogrammed from fibroblasts. Nat Neurosci 2015; 18:17-24. [PMID: 25420066 PMCID: PMC4429606 DOI: 10.1038/nn.3886] [Citation(s) in RCA: 153] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 10/29/2014] [Indexed: 02/08/2023]
Abstract
Reprogramming somatic cells from one cell fate to another can generate specific neurons suitable for disease modeling. To maximize the utility of patient-derived neurons, they must model not only disease-relevant cell classes, but also the diversity of neuronal subtypes found in vivo and the pathophysiological changes that underlie specific clinical diseases. We identified five transcription factors that reprogram mouse and human fibroblasts into noxious stimulus-detecting (nociceptor) neurons. These recapitulated the expression of quintessential nociceptor-specific functional receptors and channels found in adult mouse nociceptor neurons, as well as native subtype diversity. Moreover, the derived nociceptor neurons exhibited TrpV1 sensitization to the inflammatory mediator prostaglandin E2 and the chemotherapeutic drug oxaliplatin, modeling the inherent mechanisms underlying inflammatory pain hypersensitivity and painful chemotherapy-induced neuropathy. Using fibroblasts from patients with familial dysautonomia (hereditary sensory and autonomic neuropathy type III), we found that the technique was able to reveal previously unknown aspects of human disease phenotypes in vitro.
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Affiliation(s)
- Brian J. Wainger
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
- Department of Anesthesia, Critical Care and Pain Medicine,
Massachusetts General Hospital
- Department of Neurobiology, Harvard Medical School
| | - Elizabeth D. Buttermore
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
- Department of Neurobiology, Harvard Medical School
| | - Julia T. Oliveira
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Cassidy Mellin
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Seungkyu Lee
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
- Department of Neurobiology, Harvard Medical School
| | - Wardiya Afshar Saber
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Amy Wang
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Justin K. Ichida
- Harvard Stem Cell Institute, Department of Stem Cell and
Regenerative Biology, Harvard University
- Department of Stem Cell Biology and Regenerative Medicine, Eli
and Edythe Broad CIRM Center for Regenerative Medicine and Stem Cell Research, University of
Southern California
| | - Isaac M. Chiu
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
- Department of Neurobiology, Harvard Medical School
| | - Lee Barrett
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Eric A. Huebner
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
- Department of Neurobiology, Harvard Medical School
| | - Canan Bilgin
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Naomi Tsujimoto
- Harvard Stem Cell Institute, Department of Stem Cell and
Regenerative Biology, Harvard University
| | - Christian Brenneis
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Kush Kapur
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
| | - Lee L. Rubin
- Harvard Stem Cell Institute, Department of Stem Cell and
Regenerative Biology, Harvard University
| | - Kevin Eggan
- Harvard Stem Cell Institute, Department of Stem Cell and
Regenerative Biology, Harvard University
- The Howard Hughes Medical Institute, USA
| | - Clifford J. Woolf
- FM Kirby Neurobiology Center, Boston Children's Hospital
and Harvard Stem Cell Institute
- Department of Neurobiology, Harvard Medical School
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46
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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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47
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Lauria G, Ziegler D, Malik R, Merkies ISJ, Waxman SG, Faber CG. The role of sodium channels in painful diabetic and idiopathic neuropathy. Curr Diab Rep 2014; 14:538. [PMID: 25142720 DOI: 10.1007/s11892-014-0538-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Painful neuropathies are frequently encountered in clinical practice as an early or late complication of several systemic disorders. Among them, diabetes is one of the most important due to its epidemiology and the relevance for regulatory agencies in the assessment of efficacy of new analgesics. However, the presentation and course of painful neuropathies, as well as the response to available drugs, are highly variable and unpredictable, posing significant challenges in the management of patients. Experimental and clinical studies have suggested that polymorphisms and mutations in pain-related genes are involved in the facilitation or inhibition of nociception, and might modulate neuropathic pain and the response to analgesics in patients. Voltage-gated sodium channel genes are among the most relevant, due to the key role of these membrane proteins in the physiology of nociception and their involvement in the pathogenesis of idiopathic painful small fiber neuropathies. These compelling features make sodium channel candidate targets for a novel approach to painful diabetic and idiopathic neuropathies, which will hopefully allow a new classification of patients and more effective targeted treatments.
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Affiliation(s)
- Giuseppe Lauria
- Neuroalgology and Headache Unit, IRCCS Foundation "Carlo Besta" Neurological Institute, Via Celoria, 11, 20133, Milan, Italy,
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48
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Brouwer BA, Merkies ISJ, Gerrits MM, Waxman SG, Hoeijmakers JGJ, Faber CG. Painful neuropathies: the emerging role of sodium channelopathies. J Peripher Nerv Syst 2014; 19:53-65. [DOI: 10.1111/jns5.12071] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Brigitte A. Brouwer
- Department of Anesthesiology and Pain Management; 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
| | - Monique M. Gerrits
- Department of Clinical Genomics; Maastricht University Medical Center; Maastricht The Netherlands
| | - Stephen G. Waxman
- Department of Neurology; Yale University School of Medicine; New Haven CT USA
- Center for Neuroscience and Regeneration Research; Veterans Affairs Medical Center; West Haven CT USA
| | | | - Catharina G. Faber
- Department of Neurology; Maastricht University Medical Center; Maastricht The Netherlands
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Hirai T, Miyagawa S, Matsui K, Kurita A. [Small fiber neuropathy in a patient with complete Heerfordt syndrome manifesting as refractory facial pain]. Rinsho Shinkeigaku 2014; 54:585-8. [PMID: 25087562 DOI: 10.5692/clinicalneurol.54.585] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We report a case of complete Heerfordt syndrome accompanied by the involvement of small fiber neuropathy (SFN) manifesting as refracory facial pain. A 30-year-old man presented with pyrexia, a 2-week history of facial burning pain, and difficulty of mastication. After admission to our hospital, neurological examinations showed bilateral facial pain, trigeminal motor palsy, left facial nerve palsy, bilateral sensory neural deafness, uveitis and swelling of the parotid gland. Other examinations revealed bilateral hilar lymphadenopathy, high serum titer of angiotensin coenzyme, and no response in a tuberculin-tested, non-caseating epithelioid granuloma from lip biopsy, leading to the diagnosis of complete Heerfordt syndrome. Mandibular skin biopsy with immunostaining for PGP 9.5 showed SFN. High-dose corticosteroids proved somewhat effective against SFN as facial pain, but reducing the corticosteroid dose proved difficult, as symptoms were refractory to other immunosuppressants and pain-control drugs such as anti-epileptics and anti-depressants. The patient died of acute pancreatitis 3 years after disease onset. Autopsy showed no granuloma in hilar lymph node, trigeminal nerve, cranial base, nerve root, and muscle. SFN in this case probably represent a cause of refractory facial pain.
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Affiliation(s)
- Toshiaki Hirai
- Department of Neurology, The Jikei University Kashiwa Hospital
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50
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Hoeijmakers JGJ, Faber CG, Merkies ISJ, Waxman SG. Channelopathies, painful neuropathy, and diabetes: which way does the causal arrow point? Trends Mol Med 2014; 20:544-50. [PMID: 25008557 DOI: 10.1016/j.molmed.2014.06.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 06/09/2014] [Accepted: 06/12/2014] [Indexed: 12/13/2022]
Abstract
Diabetes mellitus, a major global health problem, is commonly associated with painful peripheral neuropathy, which can substantially erode quality of life. Despite its clinical importance, the pathophysiology of painful diabetic neuropathy is incompletely understood. It has traditionally been thought that diabetes may cause neuropathy in patients with appropriate genetic makeup. Here, we propose a hypothesis whereby painful neuropathy is not a complication of diabetes, but rather occurs as a result of mutations that, in parallel, confer vulnerability to injury in pancreatic β cells and pain-signaling dorsal root ganglion (DRG) neurons. We suggest that mutations of sodium channel NaV1.7, which is present in both cell types, may increase susceptibility for development of diabetes via β cell injury and produce painful neuropathy via a distinct effect on DRG neurons.
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Affiliation(s)
- Janneke G J Hoeijmakers
- Department of Neurology, Maastricht University Medical Center, Maastricht, 6202 AZ, The Netherlands
| | - Catharina G Faber
- Department of Neurology, Maastricht University Medical Center, Maastricht, 6202 AZ, The Netherlands
| | - Ingemar S J Merkies
- Department of Neurology, Maastricht University Medical Center, Maastricht, 6202 AZ, The Netherlands; Department of Neurology, Spaarne Hospital, Hoofddorp, 2130 AT, The Netherlands
| | - Stephen G Waxman
- Department of Neurology, Yale University School of Medicine, New Haven, CT 06515, USA; Center for Neuroscience and Regeneration Research, Veterans Affairs Medical Center, West Haven, CT 06515, USA.
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