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Adler BL, Chung T, Rowe PC, Aucott J. Dysautonomia following Lyme disease: a key component of post-treatment Lyme disease syndrome? Front Neurol 2024; 15:1344862. [PMID: 38390594 PMCID: PMC10883079 DOI: 10.3389/fneur.2024.1344862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Accepted: 01/22/2024] [Indexed: 02/24/2024] Open
Abstract
Dysautonomia, or dysfunction of the autonomic nervous system (ANS), may occur following an infectious insult and can result in a variety of debilitating, widespread, and often poorly recognized symptoms. Dysautonomia is now widely accepted as a complication of COVID-19 and is an important component of Post-Acute Sequelae of COVID-19 (PASC or long COVID). PASC shares many overlapping clinical features with other infection-associated chronic illnesses including Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Post-Treatment Lyme Disease Syndrome (PTLDS), suggesting that they may share common underlying mechanisms including autonomic dysfunction. Despite the recognition of this complication of Lyme disease in the care of patients with PTLD, there has been a scarcity of research in this field and dysautonomia has not yet been established as a complication of Lyme disease in the medical literature. In this review, we discuss the evidence implicating Borrelia burgdorferi as a cause of dysautonomia and the related symptoms, propose potential pathogenic mechanisms given our knowledge of Lyme disease and mechanisms of PASC and ME/CFS, and discuss the diagnostic evaluation and treatments of dysautonomia. We also outline gaps in the literature and priorities for future research.
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Affiliation(s)
- Brittany L Adler
- Division of Rheumatology, Johns Hopkins University, Baltimore, MD, United States
| | - Tae Chung
- Department of Physical Medicine and Rehabilitation, Johns Hopkins University, Baltimore, MD, United States
| | - Peter C Rowe
- Department of Pediatrics, Johns Hopkins University, Baltimore, MD, United States
| | - John Aucott
- Division of Rheumatology, Johns Hopkins University, Baltimore, MD, United States
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2
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Løseth S, Nebuchennykh M, Brokstad RT, Lindal S, Mellgren SI. Cutaneous nerve biopsy in patients with symptoms of small fiber neuropathy: a retrospective study. Scand J Pain 2024; 24:sjpain-2023-0071. [PMID: 38381703 DOI: 10.1515/sjpain-2023-0071] [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: 06/01/2023] [Accepted: 11/20/2023] [Indexed: 02/23/2024]
Abstract
OBJECTIVES We aimed to investigate to what extent small fiber tests were abnormal in an unselected retrospective patient material with symptoms suggesting that small fiber neuropathy (SFN) could be present, and to evaluate possible gender differences. METHODS Nerve conduction studies (NCS), skin biopsy for determination of intraepidermal nerve fiber density (IENFD) and quantitative sensory testing (QST) were performed. Z-scores were calculated from reference materials to adjust for the effects of age and gender/height. RESULTS Two hundred and three patients, 148 females and 55 males had normal NCS and were considered to have possible SFN. 45.3 % had reduced IENFD, 43.2 % of the females and 50.9 % of the males. Mean IENFD was 7.3 ± 2.6 fibers/mm in females and 6.1 ± 2.3 in males (p<0.001), but the difference was not significant when adopting Z-scores. Comparison of gender differences between those with normal and abnormal IENFD were not significant when Z-scores were applied. QST was abnormal in 50 % of the patients (48.9 % in females and 52.9 % in males). In the low IENFD group 45 cases out of 90 (50 %) were recorded with abnormal QST. In those with normal IENFD 51 of 102 (50 %) showed abnormal QST. CONCLUSIONS Less than half of these patients had reduced IENFD, and 50 % had abnormal QST. There were no gender differences. A more strict selection of patients might have increased the sensitivity, but functional changes in unmyelinated nerve fibers are also known to occur with normal IENFD. Approval to collect data was given by the Norwegian data protection authority at University Hospital of North Norway (Project no. 02028).
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Affiliation(s)
- Sissel Løseth
- Department of Neurology and Clinical Neurophysiology, University Hospital of North Norway, Tromsø, Norway
- Department of Clinical Medicine, UiT the Artic University of Norway, Tromsø, Norway
| | - Maria Nebuchennykh
- Department of Neurology and Clinical Neurophysiology, University Hospital of North Norway, Tromsø, Norway
| | - Ruth Therese Brokstad
- Department of Neurology and Clinical Neurophysiology, University Hospital of North Norway, Tromsø, Norway
| | - Sigurd Lindal
- Department of Pathology, University Hospital of North Norway, Tromsø, Norway
- Department of Clinical Medicine, UiT the Artic University of Norway, Tromsø, Norway
| | - Svein Ivar Mellgren
- Department of Neurology and Clinical Neurophysiology, University Hospital of North Norway, Tromsø, Norway
- Department of Clinical Medicine, UiT the Artic University of Norway, Tromsø, Norway
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3
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Chan ACY, Kumar S, Tan G, Wong HY, Ong JJY, Chandra B, Huang H, Sharma VK, Lai PS. Expanding the genetic causes of small-fiber neuropathy: SCN genes and beyond. Muscle Nerve 2023; 67:259-271. [PMID: 36448457 DOI: 10.1002/mus.27752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 10/31/2022] [Accepted: 11/06/2022] [Indexed: 12/05/2022]
Abstract
Small-fiber neuropathy (SFN) is a disorder that exclusively affects the small nerve fibers, sparing the large nerve fibers. Thinly myelinated Aδ-fibers and unmyelinated C-fibers are damaged, leading to development of neuropathic pain, thermal dysfunction, sensory symptoms, and autonomic disturbances. Although many SFNs are secondary and due to immunological causes or metabolic disturbances, the etiology is unknown in up to half of the patients. Over the years, this proportion of "idiopathic SFN" has decreased, as familial and genetic causes have been discovered, thus shifting a proportion of once "idiopathic" cases to the genetic category. After the discovery of SCN9A-gene variants in 2012, SCN10A and SCN11A variants have been found to be pathogenic in SFN. With improved accessibility of SFN diagnostic tools and genetic tests, many non-SCN variants and genetically inherited systemic diseases involving the small nerve fibers have also been described, but only scattered throughout the literature. There are 80 SCN variants described as causing SFN, 8 genes causing hereditary sensory autonomic neuropathies (HSAN) described with pure SFN, and at least 7 genes involved in genetically inherited systemic diseases associated with SFN. This systematic review aims to consolidate and provide an updated overview on the genetic variants of SFN to date---SCN genes and beyond. Awareness of these genetic causes of SFN is imperative for providing treatment directions, prognostication, and management of expectations for patients and their health-care providers.
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Affiliation(s)
- Amanda C Y Chan
- Division of Neurology, Department of Medicine, National University Hospital, Singapore, Singapore
- Yong Loo Ling School of Medicine, National University of Singapore, Singapore, Singapore
| | - Shivaram Kumar
- Yong Loo Ling School of Medicine, National University of Singapore, Singapore, Singapore
| | - Grace Tan
- Yong Loo Ling School of Medicine, National University of Singapore, Singapore, Singapore
| | - Hiu Yi Wong
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Hong Kong, China
- Hong Kong Center for Neurodegenerative Diseases, Hong Kong Science Park, Hong Kong, China
| | - Jonathan J Y Ong
- Division of Neurology, Department of Medicine, National University Hospital, Singapore, Singapore
- Yong Loo Ling School of Medicine, National University of Singapore, Singapore, Singapore
| | - Bharatendu Chandra
- Division of Neurology, Department of Medicine, National University Hospital, Singapore, Singapore
- Yong Loo Ling School of Medicine, National University of Singapore, Singapore, Singapore
- Division of Medical Genetics, University of Iowa, Iowa City, Iowa, USA
| | - Hua Huang
- Yong Loo Ling School of Medicine, National University of Singapore, Singapore, Singapore
| | - Vijay Kumar Sharma
- Division of Neurology, Department of Medicine, National University Hospital, Singapore, Singapore
- Yong Loo Ling School of Medicine, National University of Singapore, Singapore, Singapore
| | - Poh San Lai
- Yong Loo Ling School of Medicine, National University of Singapore, Singapore, Singapore
- Adjunct Faculty, Genome Institute of Singapore, Singapore, Singapore
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4
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Lauria G, Faber CG, Cornblath DR. Skin biopsy and small fibre neuropathies: facts and thoughts 30 years later. J Neurol Neurosurg Psychiatry 2022; 93:915-918. [PMID: 35246491 PMCID: PMC9380509 DOI: 10.1136/jnnp-2021-327742] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 01/09/2022] [Indexed: 11/18/2022]
Affiliation(s)
- Giuseppe Lauria
- Department of Clinical Neurosciences, Fondazione IRCCS Istituto Neurologico "Carlo Besta", Milan, Italy .,Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Catharina G Faber
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Center+, Maastricht, Netherlands
| | - David R Cornblath
- Department of Neurology, John Hopkins University School of Medicine, Baltimore, Maryland, USA
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5
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Starling CT, Nguyen QBD, Butler IJ, Numan MT, Hebert AA. Cutaneous manifestations of orthostatic intolerance syndromes. Int J Womens Dermatol 2021; 7:471-477. [PMID: 34621961 PMCID: PMC8484984 DOI: 10.1016/j.ijwd.2021.03.003] [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: 07/23/2020] [Revised: 02/05/2021] [Accepted: 03/05/2021] [Indexed: 11/27/2022] Open
Abstract
Dysautonomia refers to a group of autonomic nervous system disorders that affect nearly 70 million people worldwide. One subset of dysautonomia includes syndromes of orthostatic intolerance (OI), which primarily affect adolescents and women of childbearing age. Due to the variability in disease presentation, the average time from symptom onset to diagnosis of dysautonomia is 6 years. In general, there is a paucity of dermatological research articles describing patients with dysautonomia. The objective of this review is to summarize the existing literature on cutaneous manifestations in dysautonomia, with an emphasis on syndromes of OI. A PubMed database of the English-language literature (1970–2020) was searched using the terms “dysautonomia”, “orthostatic intolerance”, “cutaneous”, “skin”, “hyperhidrosis”, “hypohidrosis”, “sweat”, and other synonyms. Results showed that cutaneous manifestations of orthostatic intolerance are common and varied, with one paper citing up to 85% of patients with OI having at least one cutaneous symptom. Recognition of dermatological complaints may lead to an earlier diagnosis of orthostatic intolerance, as well as other comorbid conditions.
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Affiliation(s)
| | - Quoc-Bao D Nguyen
- Department of Dermatology, UTHealth McGovern Medical School at Houston, Houston, Texas
| | - Ian J Butler
- Department of Pediatrics, UTHealth McGovern Medical School at Houston, Houston, Texas
| | - Mohammed T Numan
- Department of Pediatrics, UTHealth McGovern Medical School at Houston, Houston, Texas
| | - Adelaide A Hebert
- Department of Dermatology, UTHealth McGovern Medical School at Houston, Houston, Texas.,Department of Pediatrics, UTHealth McGovern Medical School at Houston, Houston, Texas
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6
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Montnach J, De Waard S, Nicolas S, Burel S, Osorio N, Zoukimian C, Mantegazza M, Boukaiba R, Béroud R, Partiseti M, Delmas P, Marionneau C, De Waard M. Fluorescent- and tagged-protoxin II peptides: potent markers of the Na v 1.7 channel pain target. Br J Pharmacol 2021; 178:2632-2650. [PMID: 33742442 DOI: 10.1111/bph.15453] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 01/26/2021] [Accepted: 02/09/2021] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND AND PURPOSE Protoxin II (ProTx II) is a high affinity gating modifier that is thought to selectively block the Nav 1.7 voltage-dependent Na+ channel, a major therapeutic target for the control of pain. We aimed at producing ProTx II analogues entitled with novel functionalities for cell distribution studies and biochemical characterization of its Nav channel targets. EXPERIMENTAL APPROACH We took advantage of the high affinity properties of the peptide, combined to its slow off rate, to design a number of new tagged analogues useful for imaging and biochemistry purposes. We used high-throughput automated patch-clamp to identify the analogues best matching the native properties of ProTx II and validated them on various Nav -expressing cells in pull-down and cell distribution studies. KEY RESULTS Two of the produced ProTx II analogues, Biot-ProTx II and ATTO488-ProTx II, best emulate the pharmacological properties of unlabelled ProTx II, whereas other analogues remain high affinity blockers of Nav 1.7. The biotinylated version of ProTx II efficiently works for the pull-down of several Nav isoforms tested in a concentration-dependent manner, whereas the fluorescent ATTO488-ProTx II specifically labels the Nav 1.7 channel over other Nav isoforms tested in various experimental conditions. CONCLUSIONS AND IMPLICATIONS The properties of these ProTx II analogues as tools for Nav channel purification and cell distribution studies pave the way for a better understanding of ProTx II channel receptors in pain and their pathophysiological implications in sensory neuronal processing. The new fluorescent ProTx II should also be useful in the design of new drug screening strategies.
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Affiliation(s)
- Jérôme Montnach
- LabEx "Ion Channels, Science & Therapeutics", l'institut du thorax, INSERM, CNRS, UNIV NANTES, Nantes, France
| | - Stephan De Waard
- LabEx "Ion Channels, Science & Therapeutics", l'institut du thorax, INSERM, CNRS, UNIV NANTES, Nantes, France
| | - Sébastien Nicolas
- LabEx "Ion Channels, Science & Therapeutics", l'institut du thorax, INSERM, CNRS, UNIV NANTES, Nantes, France
| | - Sophie Burel
- LabEx "Ion Channels, Science & Therapeutics", l'institut du thorax, INSERM, CNRS, UNIV NANTES, Nantes, France
| | - Nancy Osorio
- Laboratory of Cognitive Neuroscience, UMR 7291, CNRS, Aix-Marseille University, Marseille, France
| | | | - Massimo Mantegazza
- Université Cote d'Azur, CNRS UMR 7275, Institute of Molecular and Cellular Pharmacology, Valbonne-Sophia Antipolis, France
| | - Rachid Boukaiba
- Sanofi R&D, Integrated Drug Discovery - High Content Biology, Vitry-sur-Seine, France
| | | | - Michel Partiseti
- Sanofi R&D, Integrated Drug Discovery - High Content Biology, Vitry-sur-Seine, France
| | - Patrick Delmas
- Laboratory of Cognitive Neuroscience, UMR 7291, CNRS, Aix-Marseille University, Marseille, France
| | - Céline Marionneau
- LabEx "Ion Channels, Science & Therapeutics", l'institut du thorax, INSERM, CNRS, UNIV NANTES, Nantes, France
| | - Michel De Waard
- LabEx "Ion Channels, Science & Therapeutics", l'institut du thorax, INSERM, CNRS, UNIV NANTES, Nantes, France.,Smartox Biotechnology, Saint-Egrève, France
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7
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Xenakis MN, Kapetis D, Yang Y, Gerrits MM, Heijman J, Waxman SG, Lauria G, Faber CG, Westra RL, Lindsey PJ, Smeets HJ. Hydropathicity-based prediction of pain-causing NaV1.7 variants. BMC Bioinformatics 2021; 22:212. [PMID: 33892629 PMCID: PMC8063372 DOI: 10.1186/s12859-021-04119-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 04/01/2021] [Indexed: 11/10/2022] Open
Abstract
Background Mutation-induced variations in the functional architecture of the NaV1.7 channel protein are causally related to a broad spectrum of human pain disorders. Predicting in silico the phenotype of NaV1.7 variant is of major clinical importance; it can aid in reducing costs of in vitro pathophysiological characterization of NaV1.7 variants, as well as, in the design of drug agents for counteracting pain-disease symptoms. Results In this work, we utilize spatial complexity of hydropathic effects toward predicting which NaV1.7 variants cause pain (and which are neutral) based on the location of corresponding mutation sites within the NaV1.7 structure. For that, we analyze topological and scaling hydropathic characteristics of the atomic environment around NaV1.7’s pore and probe their spatial correlation with mutation sites. We show that pain-related mutation sites occupy structural locations in proximity to a hydrophobic patch lining the pore while clustering at a critical hydropathic-interactions distance from the selectivity filter (SF). Taken together, these observations can differentiate pain-related NaV1.7 variants from neutral ones, i.e., NaV1.7 variants not causing pain disease, with 80.5\documentclass[12pt]{minimal}
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\begin{document}$$\%$$\end{document}% specificity [area under the receiver operating characteristics curve = 0.872]. Conclusions Our findings suggest that maintaining hydrophobic NaV1.7 interior intact, as well as, a finely-tuned (dictated by hydropathic interactions) distance from the SF might be necessary molecular conditions for physiological NaV1.7 functioning. The main advantage for using the presented predictive scheme is its negligible computational cost, as well as, hydropathicity-based biophysical rationalization. Supplementary Information The online version contains supplementary material available at 10.1186/s12859-021-04119-2.
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Affiliation(s)
- Makros N Xenakis
- Department of Toxicogenomics, Section Clinical Genomics, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands. .,Research School for Mental Health and Neuroscience (MHeNS), Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands.
| | - Dimos Kapetis
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta", Via Celoria 11, 20133, Milan, Italy
| | - Yang Yang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University College of Pharmacy, West Lafayette, IN, 47907, USA.,Purdue Institute for Integrative Neuroscience, West Lafayette, IN, 47907, USA
| | - Monique M Gerrits
- Department of Clinical Genetics, Maastricht University Medical Center, PO box 5800, 6202 AZ, Maastricht, The Netherlands
| | - Jordi Heijman
- Department of Cardiology, CARIM School for Cardiovascular Diseases, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
| | - Stephen G Waxman
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, 06510, USA.,Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, 06516, USA
| | - Giuseppe Lauria
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta", Via Celoria 11, 20133, Milan, Italy.,Department of Biomedical and Clinical Sciences "Luigi Sacco", University of Milan, Via G.B. Grassi 74, 20157, Milan, Italy
| | - Catharina G Faber
- Department of Neurology, Maastricht University Medical Center, PO Box 5800, 6202 AZ, Maastricht, The Netherlands
| | - Ronald L Westra
- Department of Data Science and Knowledge Engineering, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
| | - Patrick J Lindsey
- Department of Toxicogenomics, Section Clinical Genomics, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands.,Research School for Oncology and Developmental Biology (GROW), Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
| | - Hubert J Smeets
- Department of Toxicogenomics, Section Clinical Genomics, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands.,Research School for Mental Health and Neuroscience (MHeNS), Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
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8
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Xenakis MN, Kapetis D, Yang Y, Heijman J, Waxman SG, Lauria G, Faber CG, Smeets HJ, Lindsey PJ, Westra RL. Non-extensitivity and criticality of atomic hydropathicity around a voltage-gated sodium channel's pore: a modeling study. J Biol Phys 2021; 47:61-77. [PMID: 33735400 PMCID: PMC7981368 DOI: 10.1007/s10867-021-09565-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 02/02/2021] [Indexed: 01/22/2023] Open
Abstract
Voltage-gated sodium channels (NavChs) are pore-forming membrane proteins that regulate the transport of sodium ions through the cell membrane. Understanding the structure and function of NavChs is of major biophysical, as well as clinical, importance given their key role in cellular pathophysiology. In this work, we provide a computational framework for modeling system-size-dependent, i.e., cumulative, atomic properties around a NavCh's pore. We illustrate our methodologies on the bacterial NavAb channel captured in a closed-pore state where we demonstrate that the atomic environment around its pore exhibits a bi-phasic spatial organization dictated by the structural separation of the pore domains (PDs) from the voltage-sensing domains (VSDs). Accordingly, a mathematical model describing packing of atoms around NavAb's pore is constructed that allows-under certain conservation conditions-for a power-law approximation of the cumulative hydropathic dipole field effect acting along NavAb's pore. This verified the non-extensitivity hypothesis for the closed-pore NavAb channel and revealed a long-range hydropathic interactions law regulating atom-packing around the NavAb's selectivity filter. Our model predicts a PDs-VSDs coupling energy of [Formula: see text] kcal/mol corresponding to a global maximum of the atom-packing energy profile. Crucially, we demonstrate for the first time how critical phenomena can emerge in a single-channel structure as a consequence of the non-extensive character of its atomic porous environment.
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Affiliation(s)
- Markos N Xenakis
- Department of Toxicogenomics, Section Clinical Genomics, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands.
- Research School for Mental Health and Neuroscience (MHeNS), Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands.
| | - Dimos Kapetis
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta", via Celoria 11, 20133, Milan, Italy
| | - Yang Yang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University College of Pharmacy, West Lafayette, IN, 47907, USA
- Purdue Institute for Integrative Neuroscience, West Lafayette, IN, 47907, USA
| | - Jordi Heijman
- Department of Cardiology, CARIM School for Cardiovascular Diseases, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
| | - Stephen G Waxman
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, 06510, USA
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, 06516, USA
| | - Giuseppe Lauria
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta", via Celoria 11, 20133, Milan, Italy
- Department of Biomedical and Clinical Sciences "Luigi Sacco", University of Milan, via G.B. Grassi 74, 20157, Milan, Italy
| | - Catharina G Faber
- Department of Neurology, Maastricht University Medical Center, PO Box 5800, 6202 AZ, Maastricht, The Netherlands
| | - Hubert J Smeets
- Department of Toxicogenomics, Section Clinical Genomics, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
- Research School for Mental Health and Neuroscience (MHeNS), Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
| | - Patrick J Lindsey
- Department of Toxicogenomics, Section Clinical Genomics, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
- Research School for Oncology and Developmental Biology (GROW), Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
| | - Ronald L Westra
- Department of Data Science and Knowledge Engineering, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
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9
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Kerth CM, Hautvast P, Körner J, Lampert A, Meents JE. Phosphorylation of a chronic pain mutation in the voltage-gated sodium channel Nav1.7 increases voltage sensitivity. J Biol Chem 2021; 296:100227. [PMID: 33361158 PMCID: PMC7948457 DOI: 10.1074/jbc.ra120.014288] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 12/17/2020] [Accepted: 12/22/2020] [Indexed: 12/19/2022] Open
Abstract
Mutations in voltage-gated sodium channels (Navs) can cause alterations in pain sensation, such as chronic pain diseases like inherited erythromelalgia. The mutation causing inherited erythromelalgia, Nav1.7 p.I848T, is known to induce a hyperpolarized shift in the voltage dependence of activation in Nav1.7. So far, however, the mechanism to explain this increase in voltage sensitivity remains unknown. In the present study, we show that phosphorylation of the newly introduced Thr residue explains the functional change. We expressed wildtype human Nav1.7, the I848T mutant, or other mutations in HEK293T cells and performed whole-cell patch-clamp electrophysiology. As the insertion of a Thr residue potentially creates a novel phosphorylation site for Ser/Thr kinases and because Nav1.7 had been shown in Xenopus oocytes to be affected by protein kinases C and A, we used different nonselective and selective kinase inhibitors and activators to test the effect of phosphorylation on Nav1.7 in a human system. We identify protein kinase C, but not protein kinase A, to be responsible for the phosphorylation of T848 and thereby for the shift in voltage sensitivity. Introducing a negatively charged amino acid instead of the putative phosphorylation site mimics the effect on voltage gating to a lesser extent. 3D modeling using the published cryo-EM structure of human Nav1.7 showed that introduction of this negatively charged site seems to alter the interaction of this residue with the surrounding amino acids and thus to influence channel function. These results could provide new opportunities for the development of novel treatment options for patients with chronic pain.
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Affiliation(s)
- Clara M Kerth
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Petra Hautvast
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Jannis Körner
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany; Department of Anesthesiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Angelika Lampert
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany
| | - Jannis E Meents
- Institute of Physiology, Uniklinik RWTH Aachen University, Aachen, Germany.
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10
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Crandall CJ, Diamant AL, Maglione M, Thurston RC, Sinsheimer J. Genetic Variation and Hot Flashes: A Systematic Review. J Clin Endocrinol Metab 2020; 105:dgaa536. [PMID: 32797194 PMCID: PMC7538102 DOI: 10.1210/clinem/dgaa536] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 08/10/2020] [Indexed: 12/26/2022]
Abstract
CONTEXT Approximately 70% of women report experiencing vasomotor symptoms (VMS, hot flashes and/or night sweats). The etiology of VMS is not clearly understood but may include genetic factors. EVIDENCE ACQUISITION We searched PubMed and Embase in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidance. We included studies on associations between genetic variation and VMS. We excluded studies focused on medication interventions or prevention or treatment of breast cancer. EVIDENCE SYNTHESIS Of 202 unique citations, 18 citations met the inclusion criteria. Study sample sizes ranged from 51 to 17 695. Eleven of the 18 studies had fewer than 500 participants; 2 studies had 1000 or more. Overall, statistically significant associations with VMS were found for variants in 14 of the 26 genes assessed in candidate gene studies. The cytochrome P450 family 1 subfamily A member 1 (CYP1B1) gene was the focus of the largest number (n = 7) of studies, but strength and statistical significance of associations of CYP1B1 variants with VMS were inconsistent. A genome-wide association study reported statistically significant associations between 14 single-nucleotide variants in the tachykinin receptor 3 gene and VMS. Heterogeneity across trials regarding VMS measurement methods and effect measures precluded quantitative meta-analysis; there were few studies of each specific genetic variant. CONCLUSIONS Genetic variants are associated with VMS. The associations are not limited to variations in sex-steroid metabolism genes. However, studies were few and future studies are needed to confirm and extend these findings.
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Affiliation(s)
- Carolyn J Crandall
- David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, California
| | - Allison L Diamant
- David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, California
| | | | - Rebecca C Thurston
- University of Pittsburgh School of Medicine & Graduate School of Public Health, Pittsburgh, Pennsylvania
| | - Janet Sinsheimer
- David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, California
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11
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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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12
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Witty DR, Alvaro G, Derjean D, Giblin GMP, Gunn K, Large C, Macpherson DT, Morisset V, Owen D, Palmer J, Rugiero F, Tate S, Hinckley CA, Naik H. Discovery of Vixotrigine: A Novel Use-Dependent Sodium Channel Blocker for the Treatment of Trigeminal Neuralgia. ACS Med Chem Lett 2020; 11:1678-1687. [PMID: 32945812 PMCID: PMC7488392 DOI: 10.1021/acsmedchemlett.0c00263] [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: 05/17/2020] [Accepted: 07/16/2020] [Indexed: 12/19/2022] Open
Abstract
Drugs that block voltage-gated sodium channels (NaVs) have utility in treating conditions including pain, epilepsy, and cardiac arrhythmias and as anesthetics (Lancet Neurol.20109413424; Expert Opin. Ther. Pat.201020755779). The identification of compounds with improved efficacy and safety is a key aim for the discovery of improved NaV blocking drugs (Comprehensive Medicinal Chemistry III; (Elsevier, 2017; pp 131-175). We report the identification of a novel class of brain penetrant and voltage-gated sodium channel blockers, leading to the discovery of vixotrigine, a use-dependent sodium channel blocker with activity in in vivo models of pain. Vixotrigine has excellent physiocochemical properties for drug development, and both preclinical and clinical data support a safety profile suitable for potential use in neuropathic pain and other conditions. It has shown efficacy in a Phase II study for pain associated with trigeminal neuralgia.
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Affiliation(s)
- David R. Witty
- Convergence
Pharmaceuticals Ltd., a Biogen Company, Babraham Research
Campus, Cambridge CB22 3AT,
U.K.
| | - Giuseppe Alvaro
- Convergence
Pharmaceuticals Ltd., a Biogen Company, Babraham Research
Campus, Cambridge CB22 3AT,
U.K.
| | - Dominique Derjean
- Convergence
Pharmaceuticals Ltd., a Biogen Company, Babraham Research
Campus, Cambridge CB22 3AT,
U.K.
| | - Gerard M. P. Giblin
- Convergence
Pharmaceuticals Ltd., a Biogen Company, Babraham Research
Campus, Cambridge CB22 3AT,
U.K.
| | - Kevin Gunn
- Convergence
Pharmaceuticals Ltd., a Biogen Company, Babraham Research
Campus, Cambridge CB22 3AT,
U.K.
| | - Charles Large
- Convergence
Pharmaceuticals Ltd., a Biogen Company, Babraham Research
Campus, Cambridge CB22 3AT,
U.K.
| | - David T. Macpherson
- Convergence
Pharmaceuticals Ltd., a Biogen Company, Babraham Research
Campus, Cambridge CB22 3AT,
U.K.
| | - Valerie Morisset
- Convergence
Pharmaceuticals Ltd., a Biogen Company, Babraham Research
Campus, Cambridge CB22 3AT,
U.K.
| | - Davina Owen
- Convergence
Pharmaceuticals Ltd., a Biogen Company, Babraham Research
Campus, Cambridge CB22 3AT,
U.K.
| | - Joanne Palmer
- Convergence
Pharmaceuticals Ltd., a Biogen Company, Babraham Research
Campus, Cambridge CB22 3AT,
U.K.
| | - Francois Rugiero
- Convergence
Pharmaceuticals Ltd., a Biogen Company, Babraham Research
Campus, Cambridge CB22 3AT,
U.K.
| | - Simon Tate
- Convergence
Pharmaceuticals Ltd., a Biogen Company, Babraham Research
Campus, Cambridge CB22 3AT,
U.K.
| | | | - Himanshu Naik
- Biogen
Inc., 225 Binney Street, Cambridge, Massachusetts 02142,
United States
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13
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Devigili G, Cazzato D, Lauria G. Clinical diagnosis and management of small fiber neuropathy: an update on best practice. Expert Rev Neurother 2020; 20:967-980. [PMID: 32654574 DOI: 10.1080/14737175.2020.1794825] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Small fiber neuropathy (SFN) is a heterogeneous group of disorders affecting thin myelinated Aδ and unmyelinated C fibers. Common symptoms include neuropathic pain and autonomic disturbances, and the typical clinical presentation is that of a length-dependent polyneuropathy, although other distributions could be present. AREA COVERED This review focuses on several aspects of SFN including etiology, clinical presentation, diagnostic criteria and tests, management, and future perspectives. Diagnostic challenges are discussed, encompassing the role of accurate and standardized assessment of symptoms and signs and providing clues for the clinical practice. The authors discuss the evidence in support of skin biopsy and quantitative sensory testing as diagnostic tests and present an overview of other diagnostic techniques to assess sensory and autonomic fibers dysfunction. The authors also suggest a systematic approach to the etiology including a set of laboratory tests and genetic examinations of sodium channelopathies and other rare conditions that might drive the therapeutic approach based on underlying cause or symptoms treatment. EXPERT OPINION SFN provides a useful model for neuropathic pain whose known mechanisms and cause could pave the way toward personalized treatments.
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Affiliation(s)
- Grazia Devigili
- Movement Disorders Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta" , Milan, Italy
| | - Daniele Cazzato
- Neurophysiology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta" , Milan, Italy
| | - Giuseppe Lauria
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta" , Milan, Italy.,Department of Biomedical and Clinical Sciences "Luigi Sacco", University of Milan , Milan, Italy
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14
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Painful and painless mutations of SCN9A and SCN11A voltage-gated sodium channels. Pflugers Arch 2020; 472:865-880. [PMID: 32601768 PMCID: PMC7351857 DOI: 10.1007/s00424-020-02419-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 05/25/2020] [Accepted: 06/10/2020] [Indexed: 12/11/2022]
Abstract
Chronic pain is a global problem affecting up to 20% of the world’s population and has a significant economic, social and personal cost to society. Sensory neurons of the dorsal root ganglia (DRG) detect noxious stimuli and transmit this sensory information to regions of the central nervous system (CNS) where activity is perceived as pain. DRG neurons express multiple voltage-gated sodium channels that underlie their excitability. Research over the last 20 years has provided valuable insights into the critical roles that two channels, NaV1.7 and NaV1.9, play in pain signalling in man. Gain of function mutations in NaV1.7 cause painful conditions while loss of function mutations cause complete insensitivity to pain. Only gain of function mutations have been reported for NaV1.9. However, while most NaV1.9 mutations lead to painful conditions, a few are reported to cause insensitivity to pain. The critical roles these channels play in pain along with their low expression in the CNS and heart muscle suggest they are valid targets for novel analgesic drugs.
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15
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Xenakis MN, Kapetis D, Yang Y, Heijman J, Waxman SG, Lauria G, Faber CG, Smeets HJ, Westra RL, Lindsey PJ. Cumulative hydropathic topology of a voltage-gated sodium channel at atomic resolution. Proteins 2020; 88:1319-1328. [PMID: 32447794 DOI: 10.1002/prot.25951] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 03/11/2020] [Accepted: 05/14/2020] [Indexed: 11/10/2022]
Abstract
Voltage-gated sodium channels (NavChs) are biological pores that control the flow of sodium ions through the cell membrane. In humans, mutations in genes encoding NavChs can disrupt physiological cellular activity thus leading to a wide spectrum of diseases. Here, we present a topological connection between the functional architecture of a NavAb bacterial channel and accumulation of atomic hydropathicity around its pore. This connection is established via a scaling analysis methodology that elucidates how intrachannel hydropathic density variations translate into hydropathic dipole field configurations along the pore. Our findings suggest the existence of a nonrandom cumulative hydropathic topology that is organized parallel to the membrane surface so that pore's stability, as well as, gating behavior are guaranteed. Given the biophysical significance of the hydropathic effect, our study seeks to provide a computational framework for studying cumulative hydropathic topological properties of NavChs and pore-forming proteins in general.
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Affiliation(s)
- Markos N Xenakis
- Department of Genetics and Cell Biology, Section Clinical Genomics, Maastricht University, Maastricht, the Netherlands.,School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, the Netherlands
| | - Dimos Kapetis
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico "Carlo Besta", Milan, Italy
| | - Yang Yang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University College of Pharmacy, West Lafayette, Indiana, USA.,Purdue Institute for Integrative Neuroscience, West Lafayette, Indiana, USA
| | - Jordi Heijman
- Department of Cardiology, CARIM School for Cardiovascular Diseases, 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.,Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut, USA
| | - 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
| | - Catharina G Faber
- Department of Neurology, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Hubert J Smeets
- Department of Genetics and Cell Biology, Section Clinical Genomics, Maastricht University, Maastricht, the Netherlands.,School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, the Netherlands
| | - Ronald L Westra
- Department of Data Science and Knowledge Engineering, Maastricht University, Maastricht, the Netherlands
| | - Patrick J Lindsey
- Department of Genetics and Cell Biology, Section Clinical Genomics, Maastricht University, Maastricht, the Netherlands.,School for Oncology and Developmental Biology (GROW), Maastricht University, Maastricht, the Netherlands
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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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Devigili G, Rinaldo S, Lombardi R, Cazzato D, Marchi M, Salvi E, Eleopra R, Lauria G. Diagnostic criteria for small fibre neuropathy in clinical practice and research. Brain 2019; 142:3728-3736. [PMID: 31665231 PMCID: PMC6906595 DOI: 10.1093/brain/awz333] [Citation(s) in RCA: 109] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 07/06/2019] [Accepted: 09/04/2019] [Indexed: 02/06/2023] Open
Abstract
The diagnostic criteria for small fibre neuropathy are not established, influencing the approach to patients in clinical practice, their access to disease-modifying and symptomatic treatments, the use of healthcare resources, and the design of clinical trials. To address these issues, we performed a reappraisal study of 150 patients with sensory neuropathy and a prospective and follow-up validation study of 352 new subjects with suspected sensory neuropathy. Small fibre neuropathy diagnostic criteria were based on deep clinical phenotyping, quantitative sensory testing (QST) and intraepidermal nerve fibre density (IENFD). Small fibre neuropathy was ruled out in 5 of 150 patients (3.3%) of the reappraisal study. Small fibre neuropathy was diagnosed at baseline of the validation study in 149 of 352 patients (42.4%) based on the combination between two clinical signs and abnormal QST and IENFD (69.1%), abnormal QST alone (5.4%), or abnormal IENFD alone (20.1%). Eight patients (5.4%) had abnormal QST and IENFD but no clinical signs. Further, 38 patients complained of sensory symptoms but showed no clinical signs. Of those, 34 (89.4%) had normal QST and IENFD, 4 (10.5%) had abnormal QST and normal IENFD, and none had abnormal IENFD alone. At 18-month follow-up, 19 of them (56%) reported the complete recovery of symptoms and showed normal clinical, QST and IENFD findings. None of those with one single abnormal test (QST or IENFD) developed clinical signs or showed abnormal findings on the other test. Conversely, all eight patients with abnormal QST and IENFD at baseline developed clinical signs at follow-up. The combination of clinical signs and abnormal QST and/or IENFD findings can more reliably lead to the diagnosis of small fibre neuropathy than the combination of abnormal QST and IENFD findings in the absence of clinical signs. Sensory symptoms alone should not be considered a reliable screening feature. Our findings demonstrate that the combined clinical, functional and structural approach to the diagnosis of small fibre neuropathy is reliable and relevant both for clinical practice and clinical trial design.
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Affiliation(s)
- Grazia Devigili
- Movement Disorders Unit, Fondazione IRCCS Istituto Neurologico “Carlo Besta”, Milan, Italy
| | - Sara Rinaldo
- Movement Disorders Unit, Fondazione IRCCS Istituto Neurologico “Carlo Besta”, Milan, Italy
| | - Raffaella Lombardi
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico “Carlo Besta”, Milan, Italy
| | - Daniele Cazzato
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico “Carlo Besta”, Milan, Italy
| | - Margherita Marchi
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico “Carlo Besta”, Milan, Italy
| | - Erika Salvi
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico “Carlo Besta”, Milan, Italy
| | - Roberto Eleopra
- Movement Disorders Unit, Fondazione IRCCS Istituto Neurologico “Carlo Besta”, Milan, Italy
| | - Giuseppe Lauria
- Neuroalgology Unit, Fondazione IRCCS Istituto Neurologico “Carlo Besta”, Milan, Italy
- Department of Biomedical and Clinical Sciences “Luigi Sacco”, University of Milan, Milan, Italy
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18
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Calvo M, Davies AJ, Hébert HL, Weir GA, Chesler EJ, Finnerup NB, Levitt RC, Smith BH, Neely GG, Costigan M, Bennett DL. The Genetics of Neuropathic Pain from Model Organisms to Clinical Application. Neuron 2019; 104:637-653. [PMID: 31751545 PMCID: PMC6868508 DOI: 10.1016/j.neuron.2019.09.018] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 09/05/2019] [Accepted: 09/12/2019] [Indexed: 12/14/2022]
Abstract
Neuropathic pain (NeuP) arises due to injury of the somatosensory nervous system and is both common and disabling, rendering an urgent need for non-addictive, effective new therapies. Given the high evolutionary conservation of pain, investigative approaches from Drosophila mutagenesis to human Mendelian genetics have aided our understanding of the maladaptive plasticity underlying NeuP. Successes include the identification of ion channel variants causing hyper-excitability and the importance of neuro-immune signaling. Recent developments encompass improved sensory phenotyping in animal models and patients, brain imaging, and electrophysiology-based pain biomarkers, the collection of large well-phenotyped population cohorts, neurons derived from patient stem cells, and high-precision CRISPR generated genetic editing. We will discuss how to harness these resources to understand the pathophysiological drivers of NeuP, define its relationship with comorbidities such as anxiety, depression, and sleep disorders, and explore how to apply these findings to the prediction, diagnosis, and treatment of NeuP in the clinic.
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Affiliation(s)
- Margarita Calvo
- Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alexander J Davies
- Neural Injury Group, Nuffield Department of Clinical Neuroscience, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Harry L Hébert
- Chronic Pain Research Group, Division of Population Health and Genomics, Mackenzie Building, Ninewells Hospital & Medical School, University of Dundee, Dundee, UK
| | - Greg A Weir
- Neural Injury Group, Nuffield Department of Clinical Neuroscience, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | | | - Nanna B Finnerup
- Department of Clinical Medicine, Danish Pain Research Center, Aarhus University, Aarhus 8000, Denmark
| | - Roy C Levitt
- Department of Anesthesiology, Perioperative Medicine and Pain Management, and John T. MacDonald Foundation Department of Human Genetics, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Blair H Smith
- Chronic Pain Research Group, Division of Population Health and Genomics, Mackenzie Building, Ninewells Hospital & Medical School, University of Dundee, Dundee, UK
| | - G Gregory Neely
- Dr. John and Anne Chong Lab for Functional Genomics, Camperdown, University of Sydney, Sydney, NSW, Australia
| | - Michael Costigan
- Departments of Anesthesia and Neurobiology, Children's Hospital Boston and Harvard Medical School, Boston, MA, USA.
| | - David L Bennett
- Neural Injury Group, Nuffield Department of Clinical Neuroscience, John Radcliffe Hospital, University of Oxford, Oxford, UK.
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19
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Abstract
Sodium channel NaV1.7 is a major target in pain research, largely because of genetic validation. In this issue of Neuron, McDermott et al. (2019) now present a comprehensive assessment of congenital pain insensitivity due to NaV1.7 loss of function. This work and studies on NaV1.7 gain of function raise important questions about how channelopathies produce disease.
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20
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Abstract
Acute pain is adaptive, but chronic pain is a global challenge. Many chronic pain syndromes are peripheral in origin and reflect hyperactivity of peripheral pain-signaling neurons. Current treatments are ineffective or only partially effective and in some cases can be addictive, underscoring the need for better therapies. Molecular genetic studies have now linked multiple human pain disorders to voltage-gated sodium channels, including disorders characterized by insensitivity or reduced sensitivity to pain and others characterized by exaggerated pain in response to normally innocuous stimuli. Here, we review recent developments that have enhanced our understanding of pathophysiological mechanisms in human pain and advances in targeting sodium channels in peripheral neurons for the treatment of pain using novel and existing sodium channel blockers.
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Affiliation(s)
- Sulayman D Dib-Hajj
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510, USA; .,Rehabilitation Research Center, Veterans Affairs, Connecticut Healthcare System, West Haven, Connecticut 06516, USA
| | - Stephen G Waxman
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510, USA; .,Rehabilitation Research Center, Veterans Affairs, Connecticut Healthcare System, West Haven, Connecticut 06516, USA
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21
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Nicolas S, Zoukimian C, Bosmans F, Montnach J, Diochot S, Cuypers E, De Waard S, Béroud R, Mebs D, Craik D, Boturyn D, Lazdunski M, Tytgat J, De Waard M. Chemical Synthesis, Proper Folding, Na v Channel Selectivity Profile and Analgesic Properties of the Spider Peptide Phlotoxin 1. Toxins (Basel) 2019; 11:toxins11060367. [PMID: 31234412 PMCID: PMC6628435 DOI: 10.3390/toxins11060367] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 06/11/2019] [Accepted: 06/16/2019] [Indexed: 12/19/2022] Open
Abstract
Phlotoxin-1 (PhlTx1) is a peptide previously identified in tarantula venom (Phlogius species) that belongs to the inhibitory cysteine-knot (ICK) toxin family. Like many ICK-based spider toxins, the synthesis of PhlTx1 appears particularly challenging, mostly for obtaining appropriate folding and concomitant suitable disulfide bridge formation. Herein, we describe a procedure for the chemical synthesis and the directed sequential disulfide bridge formation of PhlTx1 that allows for a straightforward production of this challenging peptide. We also performed extensive functional testing of PhlTx1 on 31 ion channel types and identified the voltage-gated sodium (Nav) channel Nav1.7 as the main target of this toxin. Moreover, we compared PhlTx1 activity to 10 other spider toxin activities on an automated patch-clamp system with Chinese Hamster Ovary (CHO) cells expressing human Nav1.7. Performing these analyses in reproducible conditions allowed for classification according to the potency of the best natural Nav1.7 peptide blockers. Finally, subsequent in vivo testing revealed that intrathecal injection of PhlTx1 reduces the response of mice to formalin in both the acute pain and inflammation phase without signs of neurotoxicity. PhlTx1 is thus an interesting toxin to investigate Nav1.7 involvement in cellular excitability and pain.
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Affiliation(s)
- Sébastien Nicolas
- Institut du Thorax, Inserm UMR 1087/CNRS UMR 6291, LabEx "Ion Channels, Science & Therapeutics", F-44007 Nantes, France.
| | - Claude Zoukimian
- Smartox Biotechnology, 6 rue des Platanes, F-38120 Saint-Egrève, France.
- Department of Molecular Chemistry, Univ. Grenoble Alpes, CNRS, 570 rue de la chimie, CS 40700, 38000 Grenoble, France.
| | - Frank Bosmans
- Faculty of Medicine and Health Sciences, Department of Basic and Applied Medical Sciences, 9000 Gent, Belgium.
- Toxicology and Pharmacology, University of Leuven, Campus Gasthuisberg, P.O. Box 922, Herestraat 49, 3000 Leuven, Belgium.
| | - Jérôme Montnach
- Institut du Thorax, Inserm UMR 1087/CNRS UMR 6291, LabEx "Ion Channels, Science & Therapeutics", F-44007 Nantes, France.
| | - Sylvie Diochot
- Université Côte d'Azur, CNRS UMR7275, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 6560 Valbonne, France.
| | - Eva Cuypers
- Toxicology and Pharmacology, University of Leuven, Campus Gasthuisberg, P.O. Box 922, Herestraat 49, 3000 Leuven, Belgium.
| | - Stephan De Waard
- Institut du Thorax, Inserm UMR 1087/CNRS UMR 6291, LabEx "Ion Channels, Science & Therapeutics", F-44007 Nantes, France.
| | - Rémy Béroud
- Smartox Biotechnology, 6 rue des Platanes, F-38120 Saint-Egrève, France.
| | - Dietrich Mebs
- Institute of Legal Medicine, University of Frankfurt, Kennedyallee 104, Frankfurt, Germany.
| | - David Craik
- Institute for Molecular Bioscience, University of Queensland, Brisbane 4072, Australia.
| | - Didier Boturyn
- Department of Molecular Chemistry, Univ. Grenoble Alpes, CNRS, 570 rue de la chimie, CS 40700, 38000 Grenoble, France.
| | - Michel Lazdunski
- Université Côte d'Azur, CNRS UMR7275, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 6560 Valbonne, France.
| | - Jan Tytgat
- Toxicology and Pharmacology, University of Leuven, Campus Gasthuisberg, P.O. Box 922, Herestraat 49, 3000 Leuven, Belgium.
| | - Michel De Waard
- Institut du Thorax, Inserm UMR 1087/CNRS UMR 6291, LabEx "Ion Channels, Science & Therapeutics", F-44007 Nantes, France.
- Smartox Biotechnology, 6 rue des Platanes, F-38120 Saint-Egrève, France.
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Bennett DL, Clark AJ, Huang J, Waxman SG, Dib-Hajj SD. The Role of Voltage-Gated Sodium Channels in Pain Signaling. Physiol Rev 2019; 99:1079-1151. [DOI: 10.1152/physrev.00052.2017] [Citation(s) in RCA: 256] [Impact Index Per Article: 51.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Acute pain signaling has a key protective role and is highly evolutionarily conserved. Chronic pain, however, is maladaptive, occurring as a consequence of injury and disease, and is associated with sensitization of the somatosensory nervous system. Primary sensory neurons are involved in both of these processes, and the recent advances in understanding sensory transduction and human genetics are the focus of this review. Voltage-gated sodium channels (VGSCs) are important determinants of sensory neuron excitability: they are essential for the initial transduction of sensory stimuli, the electrogenesis of the action potential, and neurotransmitter release from sensory neuron terminals. Nav1.1, Nav1.6, Nav1.7, Nav1.8, and Nav1.9 are all expressed by adult sensory neurons. The biophysical characteristics of these channels, as well as their unique expression patterns within subtypes of sensory neurons, define their functional role in pain signaling. Changes in the expression of VGSCs, as well as posttranslational modifications, contribute to the sensitization of sensory neurons in chronic pain states. Furthermore, gene variants in Nav1.7, Nav1.8, and Nav1.9 have now been linked to human Mendelian pain disorders and more recently to common pain disorders such as small-fiber neuropathy. Chronic pain affects one in five of the general population. Given the poor efficacy of current analgesics, the selective expression of particular VGSCs in sensory neurons makes these attractive targets for drug discovery. The increasing availability of gene sequencing, combined with structural modeling and electrophysiological analysis of gene variants, also provides the opportunity to better target existing therapies in a personalized manner.
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Affiliation(s)
- David L. Bennett
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Alex J. Clark
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Jianying Huang
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Stephen G. Waxman
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
| | - Sulayman D. Dib-Hajj
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom; Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, Connecticut; and Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut
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23
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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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24
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Pediatric Erythromelalgia and SCN9A Mutations: Systematic Review and Single-Center Case Series. J Pediatr 2019; 206:217-224.e9. [PMID: 30416015 DOI: 10.1016/j.jpeds.2018.10.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 09/07/2018] [Accepted: 10/11/2018] [Indexed: 12/19/2022]
Abstract
OBJECTIVES To evaluate the clinical features of erythromelalgia in childhood associated with gain-of-function SCN9A mutations that increase activity of the Nav1.7 voltage-gated sodium channel, we conducted a systematic review of pediatric presentations of erythromelalgia related to SCN9A mutations, and compared pediatric clinical presentations of symptomatic erythromelalgia, with or without SCN9A mutations. STUDY DESIGN PubMed, Embase, and PsycINFO Databases were searched for reports of inherited erythromelalgia in childhood. Clinical features, management, and genotype were extracted. Case notes of pediatric patients with erythromelalgia from the Great Ormond Street Hospital Pain Service were reviewed for clinical features, patient-reported outcomes, and treatments. Children aged over 10 years were recruited for quantitative sensory testing. RESULTS Twenty-eight publications described erythromelalgia associated with 15 different SCN9A gene variants in 25 children. Pain was severe and often refractory to multiple treatments, including nonspecific sodium channel blockers. Skin damage or other complications of cold immersion for symptomatic relief were common (60%). SCN9A mutations resulting in greater hyperpolarizing shifts in Nav1.7 sodium channels correlated with symptom onset at younger ages (P = .016). Variability in reporting, and potential publication bias toward severe cases, limit any estimations of overall prevalence. In our case series, symptoms were similar but comorbidities were more common in children with SCN9A mutations. Quantitative sensory testing revealed marked dynamic warm allodynia. CONCLUSIONS Inherited erythromelalgia in children is associated with difficult-to-manage pain and significant morbidity. Standardized reporting of outcome and management in larger series will strengthen identification of genotype-phenotype relationships. More effective long-term therapies are a significant unmet clinical need.
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25
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Sopacua M, Hoeijmakers JGJ, Merkies ISJ, Lauria G, Waxman SG, Faber CG. Small‐fiber neuropathy: Expanding the clinical pain universe. J Peripher Nerv Syst 2019; 24:19-33. [DOI: 10.1111/jns.12298] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 11/27/2018] [Accepted: 12/14/2018] [Indexed: 12/11/2022]
Affiliation(s)
- Maurice Sopacua
- Department of Neurology, School of Mental Health and NeuroscienceMaastricht University Medical Centre+ Maastricht The Netherlands
| | - Janneke G. J. Hoeijmakers
- Department of Neurology, School of Mental Health and NeuroscienceMaastricht University Medical Centre+ Maastricht The Netherlands
| | - Ingemar S. J. Merkies
- Department of Neurology, School of Mental Health and NeuroscienceMaastricht University Medical Centre+ Maastricht The Netherlands
- Department of NeurologySt. Elisabeth Hospital Willemstad Curaçao
| | - Giuseppe Lauria
- Neuroalgology UnitIRCCS Foundation, “Carlo Besta” Neurological Institute Milan Italy
- Department of Biomedical and Clinical Sciences “Luigi Sacco”University of Milan Milan Italy
| | - Stephen G. Waxman
- Department of NeurologyYale University School of Medicine New Haven Connecticut
- Center for Neuroscience and Regeneration ResearchVA Connecticut Healthcare System West Haven Connecticut
| | - Catharina G. Faber
- Department of Neurology, School of Mental Health and NeuroscienceMaastricht University Medical Centre+ Maastricht The Netherlands
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26
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Eijkenboom I, Sopacua M, Otten AB, Gerrits MM, Hoeijmakers JG, Waxman SG, Lombardi R, Lauria G, Merkies IS, Smeets HJ, Faber CG, Vanoevelen JM. Expression of pathogenic SCN9A mutations in the zebrafish: A model to study small-fiber neuropathy. Exp Neurol 2019; 311:257-264. [DOI: 10.1016/j.expneurol.2018.10.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 09/21/2018] [Accepted: 10/10/2018] [Indexed: 01/19/2023]
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27
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Yang Y, Adi T, Effraim PR, Chen L, Dib‐Hajj SD, Waxman SG. Reverse pharmacogenomics: carbamazepine normalizes activation and attenuates thermal hyperexcitability of sensory neurons due to Na v 1.7 mutation I234T. Br J Pharmacol 2018; 175:2261-2271. [PMID: 28658526 PMCID: PMC5980548 DOI: 10.1111/bph.13935] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 04/17/2017] [Accepted: 06/05/2017] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND AND PURPOSE Pharmacotherapy for pain currently involves trial and error. A previous study on inherited erythromelalgia (a genetic model of neuropathic pain due to mutations in the sodium channel, Nav 1.7) used genomics, structural modelling and biophysical and pharmacological analyses to guide pharmacotherapy and showed that carbamazepine normalizes voltage dependence of activation of the Nav 1.7-S241T mutant channel, reducing pain in patients carrying this mutation. However, whether this approach is applicable to other Nav channel mutants is still unknown. EXPERIMENTAL APPROACH We used structural modelling, patch clamp and multi-electrode array (MEA) recording to assess the effects of carbamazepine on Nav 1.7-I234T mutant channels and on the firing of dorsal root ganglion (DRG) sensory neurons expressing these mutant channels. KEY RESULTS In a reverse engineering approach, structural modelling showed that the I234T mutation is located in atomic proximity to the carbamazepine-responsive S241T mutation and that activation of Nav 1.7-I234T mutant channels, from patients who are known to respond to carbamazepine, is partly normalized with a clinically relevant concentration (30 μM) of carbamazepine. There was significantly higher firing in intact sensory neurons expressing Nav 1.7-I234T channels, compared with neurons expressing the normal channels (Nav 1.7-WT). Pre-incubation with 30 μM carbamazepine also significantly reduced the firing of intact DRG sensory neurons expressing Nav 1.7-I234T channels. Although the expected use-dependent inhibition of Nav 1.7-WT channels by carbamazepine was confirmed, carbamazepine did not enhance use-dependent inhibition of Nav 1.7-I234T mutant channels. CONCLUSION AND IMPLICATIONS These results support the utility of a pharmacogenomic approach to treatment of pain in patients carrying sodium channel variants. LINKED ARTICLES This article is part of a themed section on Recent Advances in Targeting Ion Channels to Treat Chronic Pain. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.12/issuetoc.
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Affiliation(s)
- Yang Yang
- Department of NeurologyYale University School of MedicineNew HavenCTUSA
- Center for Neuroscience and Regeneration ResearchYale University School of MedicineNew HavenCTUSA
- Rehabilitation Research CenterVA Connecticut Healthcare SystemWest HavenCTUSA
| | - Talia Adi
- Department of NeurologyYale University School of MedicineNew HavenCTUSA
- Center for Neuroscience and Regeneration ResearchYale University School of MedicineNew HavenCTUSA
- Rehabilitation Research CenterVA Connecticut Healthcare SystemWest HavenCTUSA
| | - Philip R Effraim
- Department of NeurologyYale University School of MedicineNew HavenCTUSA
- Center for Neuroscience and Regeneration ResearchYale University School of MedicineNew HavenCTUSA
- Rehabilitation Research CenterVA Connecticut Healthcare SystemWest HavenCTUSA
- Department of AnesthesiologyYale University School of MedicineNew HavenCTUSA
| | - Lubin Chen
- Department of NeurologyYale University School of MedicineNew HavenCTUSA
- Center for Neuroscience and Regeneration ResearchYale University School of MedicineNew HavenCTUSA
- Rehabilitation Research CenterVA Connecticut Healthcare SystemWest HavenCTUSA
| | - Sulayman D Dib‐Hajj
- Department of NeurologyYale University School of MedicineNew HavenCTUSA
- Center for Neuroscience and Regeneration ResearchYale University School of MedicineNew HavenCTUSA
- Rehabilitation Research CenterVA Connecticut Healthcare SystemWest HavenCTUSA
| | - Stephen G Waxman
- Department of NeurologyYale University School of MedicineNew HavenCTUSA
- Center for Neuroscience and Regeneration ResearchYale University School of MedicineNew HavenCTUSA
- Rehabilitation Research CenterVA Connecticut Healthcare SystemWest HavenCTUSA
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Ta CM, Acheson KE, Rorsman NJG, Jongkind RC, Tammaro P. Contrasting effects of phosphatidylinositol 4,5-bisphosphate on cloned TMEM16A and TMEM16B channels. Br J Pharmacol 2017; 174:2984-2999. [PMID: 28616863 PMCID: PMC5573538 DOI: 10.1111/bph.13913] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 06/09/2017] [Accepted: 06/10/2017] [Indexed: 12/19/2022] Open
Abstract
Background and Purpose Ca2+‐activated Cl− channels (CaCCs) are gated open by a rise in intracellular Ca2+ concentration ([Ca2+]i), typically provoked by activation of Gq‐protein coupled receptors (GqPCR). GqPCR activation initiates depletion of plasmalemmal phosphatidylinositol 4,5‐bisphosphate (PIP2). Here, we determined whether PIP2 acts as a signalling lipid for CaCCs coded by the TMEM16A and TMEM16B genes. Experimental Approach Patch‐clamp electrophysiology, in conjunction with genetically encoded systems to control cellular PIP2 content, was used to define the mechanism of action of PIP2 on TMEM16A and TMEM16B channels. Key Results A water‐soluble PIP2 analogue (diC8‐PIP2) activated TMEM16A channels by up to fivefold and inhibited TMEM16B by ~0.2‐fold. The effects of diC8‐PIP2 on TMEM16A currents were especially pronounced at low [Ca2+]i. In contrast, diC8‐PIP2 modulation of TMEM16B channels did not vary over a broad [Ca2+]i range but was only detectable at highly depolarized membrane potentials. Modulation of TMEM16A and TMEM16B currents was due to changes in channel gating, while single channel conductance was unaltered. Co‐expression of TMEM16A or TMEM16B with a Danio rerio voltage‐sensitive phosphatase (DrVSP), which degrades PIP2, led to reduction and enhancement of TMEM16A and TMEM16B currents respectively. These effects were abolished by an inactivating mutation in DrVSP and antagonized by simultaneous co‐expression of a phosphatidylinositol‐4‐phosphate 5‐kinase that catalyses PIP2 formation. Conclusions and Implications PIP2 acts as a modifier of TMEM16A and TMEM16B channel gating. Drugs interacting with PIP2 signalling may affect TMEM16A and TMEM16B channel gating and have potential uses in basic science and implications for therapy.
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Affiliation(s)
- Chau M Ta
- Department of Pharmacology, University of Oxford, Oxford, UK
| | | | - Nils J G Rorsman
- Department of Pharmacology, University of Oxford, Oxford, UK.,OXION Wellcome Trust Initiative in Ion Channels and Disease, University of Oxford, Oxford, UK
| | | | - Paolo Tammaro
- Department of Pharmacology, University of Oxford, Oxford, UK.,OXION Wellcome Trust Initiative in Ion Channels and Disease, University of Oxford, Oxford, UK
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30
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Tanaka BS, Nguyen PT, Zhou EY, Yang Y, Yarov-Yarovoy V, Dib-Hajj SD, Waxman SG. Gain-of-function mutation of a voltage-gated sodium channel Na V1.7 associated with peripheral pain and impaired limb development. J Biol Chem 2017; 292:9262-9272. [PMID: 28381558 DOI: 10.1074/jbc.m117.778779] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 03/24/2017] [Indexed: 01/20/2023] Open
Abstract
Dominant mutations in voltage-gated sodium channel NaV1.7 cause inherited erythromelalgia, a debilitating pain disorder characterized by severe burning pain and redness of the distal extremities. NaV1.7 is preferentially expressed within peripheral sensory and sympathetic neurons. Here, we describe a novel NaV1.7 mutation in an 11-year-old male with underdevelopment of the limbs, recurrent attacks of burning pain with erythema, and swelling in his feet and hands. Frequency and duration of the episodes gradually increased with age, and relief by cooling became less effective. The patient's sister had short stature and reported similar complaints of erythema and burning pain, but with less intensity. Genetic analysis revealed a novel missense mutation in NaV1.7 (2567G>C; p.Gly856Arg) in both siblings. The G856R mutation, located within the DII/S4-S5 linker of the channel, substitutes a highly conserved non-polar glycine by a positively charged arginine. Voltage-clamp analysis of G856R currents revealed that the mutation hyperpolarized (-11.2 mV) voltage dependence of activation and slowed deactivation but did not affect fast inactivation, compared with wild-type channels. A mutation of Gly-856 to aspartic acid was previously found in a family with limb pain and limb underdevelopment, and its functional assessment showed hyperpolarized activation, depolarized fast inactivation, and increased ramp current. Structural modeling using the Rosetta computational modeling suite provided structural clues to the divergent effects of the substitution of Gly-856 by arginine and aspartic acid. Although the proexcitatory changes in gating properties of G856R contribute to the pathophysiology of inherited erythromelalgia, the link to limb underdevelopment is not well understood.
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Affiliation(s)
- Brian S Tanaka
- From the Department of Neurology.,the Center for Neuroscience & Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510.,the Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Phuong T Nguyen
- the Department of Physiology and Membrane Biology and.,the Biophysics Graduate Group, University of California, Davis, California 95616
| | - Eray Yihui Zhou
- the Department of Dermatology, Peking University First Hospital, Beijing 100034, China, and.,the Department of Dermatology, Beijing Tsinghua Changgung Hospital, Tsinghua University, Beijing 102218, China
| | - Yong Yang
- the Department of Dermatology, Peking University First Hospital, Beijing 100034, China, and
| | - Vladimir Yarov-Yarovoy
- the Department of Physiology and Membrane Biology and.,the Biophysics Graduate Group, University of California, Davis, California 95616
| | - Sulayman D Dib-Hajj
- From the Department of Neurology.,the Center for Neuroscience & Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510.,the Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Stephen G Waxman
- From the Department of Neurology, .,the Center for Neuroscience & Regeneration Research, Yale University School of Medicine, New Haven, Connecticut 06510.,the Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
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Vetter I, Deuis JR, Mueller A, Israel MR, Starobova H, Zhang A, Rash LD, Mobli M. NaV1.7 as a pain target – From gene to pharmacology. Pharmacol Ther 2017; 172:73-100. [DOI: 10.1016/j.pharmthera.2016.11.015] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Kapetis D, Sassone J, Yang Y, Galbardi B, Xenakis MN, Westra RL, Szklarczyk R, Lindsey P, Faber CG, Gerrits M, Merkies ISJ, Dib-Hajj SD, Mantegazza M, Waxman SG, Lauria G. Network topology of NaV1.7 mutations in sodium channel-related painful disorders. BMC SYSTEMS BIOLOGY 2017; 11:28. [PMID: 28235406 PMCID: PMC5324268 DOI: 10.1186/s12918-016-0382-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 12/20/2016] [Indexed: 11/30/2022]
Abstract
BACKGROUND Gain-of-function mutations in SCN9A gene that encodes the voltage-gated sodium channel NaV1.7 have been associated with a wide spectrum of painful syndromes in humans including inherited erythromelalgia, paroxysmal extreme pain disorder and small fibre neuropathy. These mutations change the biophysical properties of NaV1.7 channels leading to hyperexcitability of dorsal root ganglion nociceptors and pain symptoms. There is a need for better understanding of how gain-of-function mutations alter the atomic structure of Nav1.7. RESULTS We used homology modeling to build an atomic model of NaV1.7 and a network-based theoretical approach, which can predict interatomic interactions and connectivity arrangements, to investigate how pain-related NaV1.7 mutations may alter specific interatomic bonds and cause connectivity rearrangement, compared to benign variants and polymorphisms. For each amino acid substitution, we calculated the topological parameters betweenness centrality (B ct ), degree (D), clustering coefficient (CC ct ), closeness (C ct ), and eccentricity (E ct ), and calculated their variation (Δ value = mutant value -WT value ). Pathogenic NaV1.7 mutations showed significantly higher variation of |ΔB ct | compared to benign variants and polymorphisms. Using the cut-off value ±0.26 calculated by receiver operating curve analysis, we found that ΔB ct correctly differentiated pathogenic NaV1.7 mutations from variants not causing biophysical abnormalities (nABN) and homologous SNPs (hSNPs) with 76% sensitivity and 83% specificity. CONCLUSIONS Our in-silico analyses predict that pain-related pathogenic NaV1.7 mutations may affect the network topological properties of the protein and suggest |ΔB ct | value as a potential in-silico marker.
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Affiliation(s)
- Dimos Kapetis
- Bioinformatics Unit, IRCCS Foundation “Carlo Besta” Neurological Institute, Milan, Italy
- Neuroalgology Unit, IRCCS Foundation “Carlo Besta” Neurological Institute, Milan, Italy
| | - Jenny Sassone
- Neuroalgology Unit, IRCCS Foundation “Carlo Besta” Neurological Institute, Milan, Italy
- Present address: San Raffaele Scientific Institute and Vita-Salute University, Milan, Italy
| | - Yang Yang
- Department of Neurology, Yale University School of Medicine, New Haven, USA
- Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, USA
| | - Barbara Galbardi
- Bioinformatics Unit, IRCCS Foundation “Carlo Besta” Neurological Institute, Milan, Italy
| | - Markos N. Xenakis
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
- Department of Knowledge Engineering, Maastricht University, Maastricht, The Netherlands
| | - Ronald L. Westra
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
- Department of Knowledge Engineering, Maastricht University, Maastricht, The Netherlands
| | - Radek Szklarczyk
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Patrick Lindsey
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Catharina G. Faber
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
- Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Monique Gerrits
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Ingemar S. J. Merkies
- Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands
- Department of Neurology, Spaarne Hospital, Hoofddorp, The Netherlands
| | - Sulayman D. Dib-Hajj
- Department of Neurology, Yale University School of Medicine, New Haven, USA
- Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, USA
| | - Massimo Mantegazza
- Laboratory of Excellence Ion Channel Science and Therapeutics, Institute of Molecular and Cellular Pharmacology, CNRS UMR7275 & University of Nice-Sophia Antipolis, Valbonne, France
| | - Stephen G. Waxman
- Department of Neurology, Yale University School of Medicine, New Haven, USA
- Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, USA
| | - Giuseppe Lauria
- Neuroalgology Unit, IRCCS Foundation “Carlo Besta” Neurological Institute, Milan, Italy
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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 channel slow inactivation interferes with open channel block. Sci Rep 2016; 6:25974. [PMID: 27174182 PMCID: PMC4865801 DOI: 10.1038/srep25974] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 04/20/2016] [Indexed: 11/17/2022] Open
Abstract
Mutations in the voltage-gated sodium channel Nav1.7 are linked to inherited pain syndromes such as erythromelalgia (IEM) and paroxysmal extreme pain disorder (PEPD). PEPD mutations impair Nav1.7 fast inactivation and increase persistent currents. PEPD mutations also increase resurgent currents, which involve the voltage-dependent release of an open channel blocker. In contrast, IEM mutations, whenever tested, leave resurgent currents unchanged. Accordingly, the IEM deletion mutation L955 (ΔL955) fails to produce resurgent currents despite enhanced persistent currents, which have hitherto been considered a prerequisite for resurgent currents. Additionally, ΔL955 exhibits a prominent enhancement of slow inactivation (SI). We introduced mutations into Nav1.7 and Nav1.6 that either enhance or impair SI in order to investigate their effects on resurgent currents. Our results show that enhanced SI is accompanied by impaired resurgent currents, which suggests that SI may interfere with open-channel block.
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37
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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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38
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Estacion M, Vohra BPS, Liu S, Hoeijmakers J, Faber CG, Merkies ISJ, Lauria G, Black JA, Waxman SG. Ca2+ toxicity due to reverse Na+/Ca2+ exchange contributes to degeneration of neurites of DRG neurons induced by a neuropathy-associated Nav1.7 mutation. J Neurophysiol 2015; 114:1554-64. [PMID: 26156380 DOI: 10.1152/jn.00195.2015] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 07/06/2015] [Indexed: 12/19/2022] Open
Abstract
Gain-of-function missense mutations in voltage-gated sodium channel Nav1.7 have been linked to small-fiber neuropathy, which is characterized by burning pain, dysautonomia and a loss of intraepidermal nerve fibers. However, the mechanistic cascades linking Nav1.7 mutations to axonal degeneration are incompletely understood. The G856D mutation in Nav1.7 produces robust changes in channel biophysical properties, including hyperpolarized activation, depolarized inactivation, and enhanced ramp and persistent currents, which contribute to the hyperexcitability exhibited by neurons containing Nav1.8. We report here that cell bodies and neurites of dorsal root ganglion (DRG) neurons transfected with G856D display increased levels of intracellular Na(+) concentration ([Na(+)]) and intracellular [Ca(2+)] following stimulation with high [K(+)] compared with wild-type (WT) Nav1.7-expressing neurons. Blockade of reverse mode of the sodium/calcium exchanger (NCX) or of sodium channels attenuates [Ca(2+)] transients evoked by high [K(+)] in G856D-expressing DRG cell bodies and neurites. We also show that treatment of WT or G856D-expressing neurites with high [K(+)] or 2-deoxyglucose (2-DG) does not elicit degeneration of these neurites, but that high [K(+)] and 2-DG in combination evokes degeneration of G856D neurites but not WT neurites. Our results also demonstrate that 0 Ca(2+) or blockade of reverse mode of NCX protects G856D-expressing neurites from degeneration when exposed to high [K(+)] and 2-DG. These results point to [Na(+)] overload in DRG neurons expressing mutant G856D Nav1.7, which triggers reverse mode of NCX and contributes to Ca(2+) toxicity, and suggest subtype-specific blockade of Nav1.7 or inhibition of reverse NCX as strategies that might slow or prevent axon degeneration in small-fiber neuropathy.
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Affiliation(s)
- M Estacion
- 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
| | - B P S Vohra
- 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
| | - S Liu
- 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
| | - J Hoeijmakers
- Department of Neurology, University Medical Center Maastricht, Maastricht, the Netherlands
| | - C G Faber
- Department of Neurology, University Medical Center Maastricht, Maastricht, the Netherlands
| | - I S J Merkies
- Department of Neurology, University Medical Center Maastricht, Maastricht, the Netherlands; Department of Neurology, Spaarne Hospital, Hoofddorp, the Netherlands; and
| | - G Lauria
- Neuroalgology Unit IRCCS Foundation "Carlo Besta" Neurological Institute, Milan, Italy
| | - J A Black
- 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
| | - S 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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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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40
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Rice FL, Albrecht PJ, Wymer JP, Black JA, Merkies IS, Faber CG, Waxman SG. Sodium channel Nav1.7 in vascular myocytes, endothelium, and innervating axons in human skin. Mol Pain 2015; 11:26. [PMID: 25957174 PMCID: PMC4447014 DOI: 10.1186/s12990-015-0024-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 04/24/2015] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The skin is a morphologically complex organ that serves multiple complementary functions, including an important role in thermoregulation, which is mediated by a rich vasculature that is innervated by sympathetic and sensory endings. Two autosomal dominant disorders characterized by episodes of severe pain, inherited erythromelalgia (IEM) and paroxysmal extreme pain disorder (PEPD) have been directly linked to mutations that enhance the function of sodium channel Nav1.7. Pain attacks are accompanied by reddening of the skin in both disorders. Nav1.7 is known to be expressed at relatively high levels within both dorsal root ganglion (DRG) and sympathetic ganglion neurons, and mutations that enhance the activity of Nav1.7 have been shown to have profound effects on the excitability of both cell-types, suggesting that dysfunction of sympathetic and/or sensory fibers, which release vasoactive peptides at skin vasculature, may contribute to skin reddening in IEM and PEPD. RESULTS In the present study, we demonstrate that smooth muscle cells of cutaneous arterioles and arteriole-venule shunts (AVS) in the skin express sodium channel Nav1.7. Moreover, Nav1.7 is expressed by endothelial cells lining the arterioles and AVS and by sensory and sympathetic fibers innervating these vascular elements. CONCLUSIONS These observations suggest that the activity of mutant Nav1.7 channels in smooth muscle cells of skin vasculature and innervating sensory and sympathetic fibers contribute to the skin reddening and/or pain in IEM and PEPD.
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Affiliation(s)
- Frank L Rice
- Integrated Tissue Dynamics, LLC, Rensselaer, NY, 12144, USA.
| | - Phillip J Albrecht
- Integrated Tissue Dynamics, LLC, Rensselaer, NY, 12144, USA. .,Department of Neurology, Albany Medical College, Albany, NY, 12209, USA.
| | - James P Wymer
- Department of Neurology, Albany Medical College, Albany, NY, 12209, USA.
| | - Joel A Black
- Center for Neuroscience & Regeneration Research, Yale University School of Medicine, West Haven, CT, 06516, USA. .,Rehabilitation Research Center, VA Connecticut Healthcare System, West Haven, CT, 06516, USA.
| | - Ingemar Sj Merkies
- Department of Neurology, Spaarne Hospital, Hoofddorp, the Netherlands. .,Department of Neurology, Maastricht University Medical Center, Maastricht, the Netherlands.
| | - Catharina G Faber
- Department of Neurology, Maastricht University Medical Center, Maastricht, the Netherlands.
| | - Stephen G Waxman
- Center for Neuroscience & Regeneration Research, Yale University School of Medicine, West Haven, CT, 06516, USA. .,Rehabilitation Research Center, VA Connecticut Healthcare System, West Haven, CT, 06516, USA.
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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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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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Abstract
Voltage-gated sodium channels (NaV) play a crucial role in development and propagation of action potentials in neurons and muscle cells. NaV1.7 channels take a special place in modern science since it is believed that they contribute to nerve hyperexcitability. Mutations of the gene SCN9A, which codes the α subunit of NaV1.7 channels, are associated with pain perception disorders (primary erythermalgia, congenital analgesia, and paroxysmal pain disorder). It is considered that the SCN9A gene mutations may cause variations in sensitivity to pain, from complete insensitivity to extreme sensitivity. Further research of the SCN9A gene polymorphism influence on pain sensitivity is essential for the understanding of the pathophysiology of pain and the development of the appropriate targeted pain treatment.
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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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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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Zhang Z, Schmelz M, Segerdahl M, Quiding H, Centerholt C, Juréus A, Carr TH, Whiteley J, Salter H, Kvernebo MS, Ørstavik K, Helås T, Kleggetveit IP, Lunden LK, Jørum E. Exonic mutations in SCN9A (NaV1.7) are found in a minority of patients with erythromelalgia. Scand J Pain 2014; 5:217-225. [DOI: 10.1016/j.sjpain.2014.09.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 09/03/2014] [Indexed: 10/24/2022]
Abstract
Abstract
Background and aim
“Gain-of-function” mutations in voltage-gated sodium channel NaV1.7 have been linked to erythromelalgia (EM), characterized by painful hot and red hands and feet. We investigated the proportion of patients with EM that carry a mutation in NaV1.7 or in other pain-related genes and studied possible clinical differences.
Methods
In this study, 48 patients with EM were screened for mutations in a total of 29 candidate genes, including all sodium channel subunits, transient receptor potential channels (TRPA1, TRPV1, TRPM8), neurotrophic factors (NGF, NGFR, BDNF, GDNF, NTRK1 and WNK1) and other known pain-related genes (CACNG2, KCNS1, COMT, P2RX3, TAC1, TACR1), using a combination of next generation sequencing and classical Sanger sequencing.
Results
In 7/48 patients protein-modifying mutations of NaV1.7 (P187L, I228M, I848T (n = 4) and N1245S) were identified. Patients with the I848T mutation could be identified clinically based on early onset and severity of the disease. In contrast, there were no clinical characteristics that differentiated the other patients with NaV1.7 mutation from those patients without. We also found more than twenty rare protein-modifying genetic variants in the genes coding for sodium channels (NaV1.8, NaV1.9, NaV1.6, NaV1.5, NaV2.1, SCN1B, SCN3B), transient receptor potential channel (TRPA1, TRPV1), and other pain-related targets (WNK1 and NGFR).
Conclusion
We conclude that functionally characterized mutations of NaV1.7 (I848T) are present only in a minority of patient with EM. Albeit the majority of patients (27/48) carried rare protein-modifying mutations the vast majority of those will most probably not be causally linked to their disease.
Implications
The key question remaining to be solved is the possible role of rare variants of NaV1.8, NaV1.9, or beta-subunits in provoking chronic pain conditions or even EM.
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Affiliation(s)
| | - Martin Schmelz
- Department of Anesthesiology Mannheim , Heidelberg University , Heidelberg , Germany
| | - Märta Segerdahl
- AstraZeneca R&D , Södertälje , Sweden
- Department of Physiology and Pharmacology , Karolinska Institute , Stockholm , Sweden
| | | | | | | | | | | | - Hugh Salter
- AstraZeneca Translational Science Centre , Department of Clinical Neuroscience , Karolinska Institutet , Karolinska , Sweden
| | | | - Kristin Ørstavik
- Section of Clinical Neurophysiology , Department of Neurology , Oslo University Hospital-Rikshospitalet , Oslo , Norway
| | - Tormod Helås
- Section of Clinical Neurophysiology , Department of Neurology , Oslo University Hospital-Rikshospitalet , Oslo , Norway
| | - Inge-Petter Kleggetveit
- Section of Clinical Neurophysiology , Department of Neurology , Oslo University Hospital-Rikshospitalet , Oslo , Norway
| | - Lars Kristian Lunden
- Section of Clinical Neurophysiology , Department of Neurology , Oslo University Hospital-Rikshospitalet , Oslo , Norway
| | - Ellen Jørum
- Section of Clinical Neurophysiology , Department of Neurology , Oslo University Hospital-Rikshospitalet , Oslo , Norway
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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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Paroxysmal itch caused by gain-of-function Nav1.7 mutation. Pain 2014; 155:1702-1707. [PMID: 24820863 DOI: 10.1016/j.pain.2014.05.006] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 04/19/2014] [Accepted: 05/02/2014] [Indexed: 11/24/2022]
Abstract
Itch is a common experience. It can occur in the course of systemic diseases and can be a manifestation of allergies or a consequence of diseases affecting the somatosensory pathway. We describe a kindred characterized by paroxysmal itch caused by a variant in SCN9A gene encoding for the Nav1.7 sodium channel. Patients underwent clinical and somatosensory profile assessment by quantitative sensory testing, nerve conduction study, autonomic cardiovascular reflex, and sympathetic skin response examination, skin biopsy with quantification of intraepidermal nerve fiber density, and SCN9A mutational analysis. The index patient, her mother, and a sister presented with a stereotypical clinical picture characterized by paroxysmal itch attacks involving the shoulders, upper back, and upper limbs, followed by transient burning pain, and triggered by environmental warmth, hot drinks, and spicy food. Somatosensory profile assessment demonstrated a remarkably identical pattern of increased cold and pain thresholds and paradoxical heat sensation. Autonomic tests were negative, whereas skin biopsy revealed decreased intraepidermal nerve fiber density in 2 of the 3 patients. All affected members harbored the 2215A>G I739V substitution in exon 13 of SCN9A gene. Pregabalin treatment reduced itch intensity and attack frequency in all patients. The co-segregation of the I739V variant in the affected members of the family provides evidence, for the first time, that paroxysmal itch can be related to a mutation in sodium channel gene.
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Huang J, Han C, Estacion M, Vasylyev D, Hoeijmakers JGJ, Gerrits MM, Tyrrell L, Lauria G, Faber CG, Dib-Hajj SD, Merkies ISJ, Waxman SG. Gain-of-function mutations in sodium channel NaV1.9 in painful neuropathy. Brain 2014; 137:1627-42. [DOI: 10.1093/brain/awu079] [Citation(s) in RCA: 197] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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