101
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Hover S, Foster B, Barr JN, Mankouri J. Viral dependence on cellular ion channels - an emerging anti-viral target? J Gen Virol 2017; 98:345-351. [PMID: 28113044 DOI: 10.1099/jgv.0.000712] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The broad range of cellular functions governed by ion channels represents an attractive target for viral manipulation. Indeed, modulation of host cell ion channel activity by viral proteins is being increasingly identified as an important virus-host interaction. Recent examples have demonstrated that virion entry, virus egress and the maintenance of a cellular environment conducive to virus persistence are, in part, dependent on virus manipulation of ion channel activity. Most excitingly, evidence has emerged that targeting ion channels pharmacologically can impede virus life cycles. Here, we discuss current examples of virus-ion channel interactions and the potential of targeting ion channel function as a new, pharmacologically safe and broad-ranging anti-viral therapeutic strategy.
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Affiliation(s)
- Samantha Hover
- School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Becky Foster
- School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - John N Barr
- School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Jamel Mankouri
- School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
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102
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Poroca DR, Pelis RM, Chappe VM. ClC Channels and Transporters: Structure, Physiological Functions, and Implications in Human Chloride Channelopathies. Front Pharmacol 2017; 8:151. [PMID: 28386229 PMCID: PMC5362633 DOI: 10.3389/fphar.2017.00151] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 03/09/2017] [Indexed: 02/04/2023] Open
Abstract
The discovery of ClC proteins at the beginning of the 1990s was important for the development of the Cl- transport research field. ClCs form a large family of proteins that mediate voltage-dependent transport of Cl- ions across cell membranes. They are expressed in both plasma and intracellular membranes of cells from almost all living organisms. ClC proteins form transmembrane dimers, in which each monomer displays independent ion conductance. Eukaryotic members also possess a large cytoplasmic domain containing two CBS domains, which are involved in transport modulation. ClC proteins function as either Cl- channels or Cl-/H+ exchangers, although all ClC proteins share the same basic architecture. ClC channels have two gating mechanisms: a relatively well-studied fast gating mechanism, and a slow gating mechanism, which is poorly defined. ClCs are involved in a wide range of physiological processes, including regulation of resting membrane potential in skeletal muscle, facilitation of transepithelial Cl- reabsorption in kidneys, and control of pH and Cl- concentration in intracellular compartments through coupled Cl-/H+ exchange mechanisms. Several inherited diseases result from C1C gene mutations, including myotonia congenita, Bartter's syndrome (types 3 and 4), Dent's disease, osteopetrosis, retinal degeneration, and lysosomal storage diseases. This review summarizes general features, known or suspected, of ClC structure, gating and physiological functions. We also discuss biophysical properties of mammalian ClCs that are directly involved in the pathophysiology of several human inherited disorders, or that induce interesting phenotypes in animal models.
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Affiliation(s)
- Diogo R Poroca
- Department of Physiology and Biophysics, Dalhousie University, Halifax NS, Canada
| | - Ryan M Pelis
- Department of Pharmacology, Dalhousie University, Halifax NS, Canada
| | - Valérie M Chappe
- Department of Physiology and Biophysics, Dalhousie University, Halifax NS, Canada
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103
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Guardiani C, Rodger PM, Fedorenko OA, Roberts SK, Khovanov IA. Sodium Binding Sites and Permeation Mechanism in the NaChBac Channel: A Molecular Dynamics Study. J Chem Theory Comput 2017; 13:1389-1400. [PMID: 28024121 DOI: 10.1021/acs.jctc.6b01035] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
NaChBac was the first discovered bacterial sodium voltage-dependent channel, yet computational studies are still limited due to the lack of a crystal structure. In this work, a pore-only construct built using the NavMs template was investigated using unbiased molecular dynamics and metadynamics. The potential of mean force (PMF) from the unbiased run features four minima, three of which correspond to sites IN, CEN, and HFS discovered in NavAb. During the run, the selectivity filter (SF) is spontaneously occupied by two ions, and frequent access of a third one is often observed. In the innermost sites IN and CEN, Na+ is fully hydrated by six water molecules and occupies an on-axis position. In site HFS sodium interacts with a glutamate and a serine from the same subunit and is forced to adopt an off-axis placement. Metadynamics simulations biasing one and two ions show an energy barrier in the SF that prevents single-ion permeation. An analysis of the permeation mechanism was performed both computing minimum energy paths in the axial-axial PMF and through a combination of Markov state modeling and transition path theory. Both approaches reveal a knock-on mechanism involving at least two but possibly three ions. The currents predicted from the unbiased simulation using linear response theory are in excellent agreement with single-channel patch-clamp recordings.
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Affiliation(s)
| | | | - Olena A Fedorenko
- Division of Biomedical and Life Sciences, Lancaster University , Lancaster, United Kingdom
| | - Stephen K Roberts
- Division of Biomedical and Life Sciences, Lancaster University , Lancaster, United Kingdom
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104
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Structure-based assessment of disease-related mutations in human voltage-gated sodium channels. Protein Cell 2017; 8:401-438. [PMID: 28150151 PMCID: PMC5445024 DOI: 10.1007/s13238-017-0372-z] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 01/09/2017] [Indexed: 12/15/2022] Open
Abstract
Voltage-gated sodium (Nav) channels are essential for the rapid upstroke of action potentials and the propagation of electrical signals in nerves and muscles. Defects of Nav channels are associated with a variety of channelopathies. More than 1000 disease-related mutations have been identified in Nav channels, with Nav1.1 and Nav1.5 each harboring more than 400 mutations. Nav channels represent major targets for a wide array of neurotoxins and drugs. Atomic structures of Nav channels are required to understand their function and disease mechanisms. The recently determined atomic structure of the rabbit voltage-gated calcium (Cav) channel Cav1.1 provides a template for homology-based structural modeling of the evolutionarily related Nav channels. In this Resource article, we summarized all the reported disease-related mutations in human Nav channels, generated a homologous model of human Nav1.7, and structurally mapped disease-associated mutations. Before the determination of structures of human Nav channels, the analysis presented here serves as the base framework for mechanistic investigation of Nav channelopathies and for potential structure-based drug discovery.
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105
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Nibbeling EAR, Delnooz CCS, de Koning TJ, Sinke RJ, Jinnah HA, Tijssen MAJ, Verbeek DS. Using the shared genetics of dystonia and ataxia to unravel their pathogenesis. Neurosci Biobehav Rev 2017; 75:22-39. [PMID: 28143763 DOI: 10.1016/j.neubiorev.2017.01.033] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 12/09/2016] [Accepted: 01/24/2017] [Indexed: 12/13/2022]
Abstract
In this review we explore the similarities between spinocerebellar ataxias and dystonias, and suggest potentially shared molecular pathways using a gene co-expression network approach. The spinocerebellar ataxias are a group of neurodegenerative disorders characterized by coordination problems caused mainly by atrophy of the cerebellum. The dystonias are another group of neurological movement disorders linked to basal ganglia dysfunction, although evidence is now pointing to cerebellar involvement as well. Our gene co-expression network approach identified 99 shared genes and showed the involvement of two major pathways: synaptic transmission and neurodevelopment. These pathways overlapped in the two disorders, with a large role for GABAergic signaling in both. The overlapping pathways may provide novel targets for disease therapies. We need to prioritize variants obtained by whole exome sequencing in the genes associated with these pathways in the search for new pathogenic variants, which can than be used to help in the genetic counseling of patients and their families.
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Affiliation(s)
- Esther A R Nibbeling
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands
| | - Cathérine C S Delnooz
- University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands
| | - Tom J de Koning
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands
| | - Richard J Sinke
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands
| | - Hyder A Jinnah
- Departments of Neurology, Human Genetics and Pediatrics, Emory Clinic, Atlanta, USA
| | - Marina A J Tijssen
- University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands
| | - Dineke S Verbeek
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands.
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106
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Milton J, Wu J, Campbell SA, Bélair J. Outgrowing Neurological Diseases: Microcircuits, Conduction Delay and Childhood Absence Epilepsy. COMPUTATIONAL NEUROLOGY AND PSYCHIATRY 2017. [DOI: 10.1007/978-3-319-49959-8_2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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107
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Ledwitch KV, Roberts AG. Cardiovascular Ion Channel Inhibitor Drug-Drug Interactions with P-glycoprotein. AAPS JOURNAL 2016; 19:409-420. [PMID: 28028729 DOI: 10.1208/s12248-016-0023-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 11/19/2016] [Indexed: 12/31/2022]
Abstract
P-glycoprotein (Pgp) is an ATP-binding cassette (ABC) transporter that plays a major role in cardiovascular drug disposition by effluxing a chemically and structurally diverse range of cardiovascular therapeutics. Unfortunately, drug-drug interactions (DDIs) with the transporter have become a major roadblock to effective cardiovascular drug administration because they can cause adverse drug reactions (ADRs) or reduce the efficacy of drugs. Cardiovascular ion channel inhibitors are particularly susceptible to DDIs and ADRs with Pgp because they often have low therapeutic indexes and are commonly coadministered with other drugs that are also Pgp substrates. DDIs from cardiovascular ion channel inhibitors with the transporter occur because of inhibition or induction of the transporter and the transporter's tissue and cellular localization. Inhibiting Pgp can increase absorption and reduce excretion of drugs, leading to elevated drug plasma concentrations and drug toxicity. In contrast, inducing Pgp can have the opposite effect by reducing the drug plasma concentration and its efficacy. A number of in vitro and in vivo studies have already demonstrated DDIs from several cardiovascular ion channel inhibitors with human Pgp and its animal analogs, including verapamil, digoxin, and amiodarone. In this review, Pgp-mediated DDIs and their effects on pharmacokinetics for different categories of cardiovascular ion channel inhibitors are discussed. This information is essential for improving pharmacokinetic predictions of cardiovascular therapeutics, for safer cardiovascular drug administration and for mitigating ADRs emanating from Pgp.
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Affiliation(s)
- Kaitlyn V Ledwitch
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 240 W. Green St., Athens, Georgia, 30602, USA
| | - Arthur G Roberts
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 240 W. Green St., Athens, Georgia, 30602, USA.
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108
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Beyder A, Farrugia G. Ion channelopathies in functional GI disorders. Am J Physiol Gastrointest Liver Physiol 2016; 311:G581-G586. [PMID: 27514480 PMCID: PMC5142191 DOI: 10.1152/ajpgi.00237.2016] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 08/07/2016] [Indexed: 01/31/2023]
Abstract
In the gastrointestinal (GI) tract, abnormalities in secretion, absorption, motility, and sensation have been implicated in functional gastrointestinal disorders (FGIDs). Ion channels play important roles in all these GI functions. Disruptions of ion channels' ability to conduct ions can lead to diseases called ion channelopathies. Channelopathies can result from changes in ion channel biophysical function or expression due to mutations, posttranslational modification, and accessory protein malfunction. Channelopathies are strongly established in the fields of cardiology and neurology, but ion channelopathies are only beginning to be recognized in gastroenterology. In this review, we describe the state of the emerging field of GI ion channelopathies. Several recent discoveries show that channelopathies result in alterations in GI motility, secretion, and sensation. In the epithelium, mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) or CFTR-associating proteins result in channelopathies with constipation or diarrhea as phenotypes. In the muscle, mutations in the SCN5A-encoded voltage-gated sodium channel NaV1.5 are associated with irritable bowel syndrome. In the sensory nerves, channelopathies of voltage-gated sodium channels NaV1.7 and NaV1.9 (encoded by SCN9A, SCN11A, respectively) manifest by either GI hyper- or hyposensation. Recent advances in structural biology and ion channel biophysics, coupled with personalized medicine, have fueled rapid discoveries of novel channelopathies and direct drug targeting of specific channelopathies. In summary, the emerging field of GI ion channelopathies has significant implications for functional GI disease stratification, diagnosis, and treatment.
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Affiliation(s)
- Arthur Beyder
- Enteric Neuroscience Program, Division of Gastroenterology & Hepatology, Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
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109
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Zaccagnino A, Pilarsky C, Tawfik D, Sebens S, Trauzold A, Novak I, Schwab A, Kalthoff H. In silico analysis of the transportome in human pancreatic ductal adenocarcinoma. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2016; 45:749-763. [PMID: 27652669 DOI: 10.1007/s00249-016-1171-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 07/18/2016] [Accepted: 08/30/2016] [Indexed: 12/14/2022]
Abstract
The altered expression and/or activity of ion channels and transporters (transportome) have been associated with malignant behavior of cancer cells and were proposed to be a hallmark of cancer. However, the impact of altered transportome in epithelial cancers, such as pancreatic ductal adenocarcinoma (PDAC), as well as its pathophysiological consequences, still remains unclear. Here, we report the in silico analysis of 840 transportome genes in PDAC patients' tissues. Our study was focused on the transportome changes and their correlation with functional and behavioral responses in PDAC tumor and stromal compartments. The dysregulated gene expression datasets were filtered using a cut-off of fold-change values ≤-2 or ≥2 (adjusted p value ≤0.05). The dysregulated transportome genes were clearly associated with impaired physiological secretory mechanisms and/or pH regulation, control of cell volume, and cell polarity. Additionally, some down-regulated transportome genes were found to be closely linked to epithelial cell differentiation. Furthermore, the observed decrease in genes coding for calcium and chloride transport might be a mechanism for evasion of apoptosis. In conclusion, the current work provides a comprehensive overview of the altered transportome expression and its association with predicted PDAC malignancy with special focus on the epithelial compartment.
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Affiliation(s)
- A Zaccagnino
- Institute for Experimental Cancer Research, Christian-Albrechts-University Kiel, UKSH, Campus Kiel, Arnold-Heller-Str. 3, 24105, Kiel, Germany.
| | - C Pilarsky
- Department of Surgery, University Clinic, Krankenhausstr. 12, 91054, Erlangen, Germany
| | - D Tawfik
- Institute for Experimental Cancer Research, Christian-Albrechts-University Kiel, UKSH, Campus Kiel, Arnold-Heller-Str. 3, 24105, Kiel, Germany
| | - S Sebens
- Institute for Experimental Cancer Research, Christian-Albrechts-University Kiel, UKSH, Campus Kiel, Arnold-Heller-Str. 3, 24105, Kiel, Germany
| | - A Trauzold
- Institute for Experimental Cancer Research, Christian-Albrechts-University Kiel, UKSH, Campus Kiel, Arnold-Heller-Str. 3, 24105, Kiel, Germany
| | - I Novak
- Section for Cell Biology and Physiology, Department of Biology, Faculty of Science, University of Copenhagen, Universitetsparken 13, 2100, Copenhagen, Denmark
| | - A Schwab
- Institute of Physiology II, University of Muenster, Robert-Koch-Str. 27 b, 48149, Muenster, Germany
| | - H Kalthoff
- Institute for Experimental Cancer Research, Christian-Albrechts-University Kiel, UKSH, Campus Kiel, Arnold-Heller-Str. 3, 24105, Kiel, Germany.
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110
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Singh D, Lau M, Ayers T, Singh Y, Akingbola O, Barbiero L, Nelson S. De Novo Heterogeneous Mutations in SCN2A and GRIN2A Genes and Seizures With Ictal Vocalizations. Clin Pediatr (Phila) 2016; 55:867-70. [PMID: 26283219 DOI: 10.1177/0009922815601060] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Dinesh Singh
- Tulane University School of Medicine, New Orleans, LA, USA
| | - Monica Lau
- Tulane University School of Medicine, New Orleans, LA, USA
| | - Travis Ayers
- Tulane University School of Medicine, New Orleans, LA, USA
| | - Yashna Singh
- Tulane University School of Medicine, New Orleans, LA, USA
| | | | - Lisa Barbiero
- Tulane University School of Medicine, New Orleans, LA, USA
| | - Stephen Nelson
- Tulane University School of Medicine, New Orleans, LA, USA
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111
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Agnati LF, Marcoli M, Maura G, Fuxe K, Guidolin D. The multi-facet aspects of cell sentience and their relevance for the integrative brain actions: role of membrane protein energy landscape. Rev Neurosci 2016; 27:347-63. [DOI: 10.1515/revneuro-2015-0049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 11/11/2015] [Indexed: 12/14/2022]
Abstract
AbstractSeveral ion channels can be randomly and spontaneously in an open state, allowing the exchange of ion fluxes between extracellular and intracellular environments. We propose that the random changes in the state of ion channels could be also due to proteins exploring their energy landscapes. Indeed, proteins can modify their steric conformation under the effects of the physicochemical parameters of the environments with which they are in contact, namely, the extracellular, intramembrane and intracellular environments. In particular, it is proposed that the random walk of proteins in their energy landscape is towards attractors that can favor the open or close condition of the ion channels and/or intrinsic activity of G-protein-coupled receptors. The main aspect of the present proposal is that some relevant physicochemical parameters of the environments (e.g. molecular composition, temperature, electrical fields) with which some signaling-involved plasma membrane proteins are in contact alter their conformations. In turn, these changes can modify their information handling via a modulatory action on their random walk towards suitable attractors of their energy landscape. Thus, spontaneous and/or signal-triggered electrical activities of neurons occur that can have emergent properties capable of influencing the integrative actions of brain networks. Against this background, Cook’s hypothesis on ‘cell sentience’ is developed by proposing that physicochemical parameters of the environments with which the plasma-membrane proteins of complex cellular networks are in contact fulfill a fundamental role in their spontaneous and/or signal-triggered activity. Furthermore, it is proposed that a specialized organelle, the primary cilium, which is present in most cells (also neurons and astrocytes), could be of peculiar importance to pick up chemical signals such as ions and transmitters and to detect physical signals such as pressure waves, thermal gradients, and local field potentials.
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Affiliation(s)
| | - Manuela Marcoli
- 3University of Genova, Department of Pharmacy and Center of Excellence for Biomedical Research, Viale Cembrano 4, I-16148 Genova, Italy
| | - Guido Maura
- 3University of Genova, Department of Pharmacy and Center of Excellence for Biomedical Research, Viale Cembrano 4, I-16148 Genova, Italy
| | - Kjell Fuxe
- 2Karolinska Institutet, Department of Neuroscience, S-17177 Stockholm, Sweden
| | - Diego Guidolin
- 4University of Padova, Department of Molecular Medicine, I-35122 Padova, Italy
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112
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Hinard V, Britan A, Rougier JS, Bairoch A, Abriel H, Gaudet P. ICEPO: the ion channel electrophysiology ontology. DATABASE-THE JOURNAL OF BIOLOGICAL DATABASES AND CURATION 2016; 2016:baw017. [PMID: 27055825 PMCID: PMC4823818 DOI: 10.1093/database/baw017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 02/03/2016] [Indexed: 01/19/2023]
Abstract
Ion channels are transmembrane proteins that selectively allow ions to flow across the plasma membrane and play key roles in diverse biological processes. A multitude of diseases, called channelopathies, such as epilepsies, muscle paralysis, pain syndromes, cardiac arrhythmias or hypoglycemia are due to ion channel mutations. A wide corpus of literature is available on ion channels, covering both their functions and their roles in disease. The research community needs to access this data in a user-friendly, yet systematic manner. However, extraction and integration of this increasing amount of data have been proven to be difficult because of the lack of a standardized vocabulary that describes the properties of ion channels at the molecular level. To address this, we have developed Ion Channel ElectroPhysiology Ontology (ICEPO), an ontology that allows one to annotate the electrophysiological parameters of the voltage-gated class of ion channels. This ontology is based on a three-state model of ion channel gating describing the three conformations/states that an ion channel can adopt: closed, open and inactivated. This ontology supports the capture of voltage-gated ion channel electrophysiological data from the literature in a structured manner and thus enables other applications such as querying and reasoning tools. Here, we present ICEPO (ICEPO ftp site: ftp://ftp.nextprot.org/pub/current_release/controlled_vocabularies/), as well as examples of its use.
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Affiliation(s)
- V Hinard
- CALIPHO Group, SIB Swiss Institute of Bioinformatics, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland
| | - A Britan
- CALIPHO Group, SIB Swiss Institute of Bioinformatics, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland
| | - J S Rougier
- University of Bern, Murtenstrasse 35, CH-3008 Bern, Switzerland and
| | - A Bairoch
- CALIPHO Group, SIB Swiss Institute of Bioinformatics, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland Department of Human Protein Science, University of Geneva Medical School, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland
| | - H Abriel
- University of Bern, Murtenstrasse 35, CH-3008 Bern, Switzerland and
| | - P Gaudet
- CALIPHO Group, SIB Swiss Institute of Bioinformatics, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland Department of Human Protein Science, University of Geneva Medical School, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland
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113
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Ahmed A, Phillips JR. Teenage pregnancy with catecholaminergic polymorphic ventricular tachycardia and documented ICD discharges. Clin Case Rep 2016; 4:361-5. [PMID: 27099728 PMCID: PMC4831384 DOI: 10.1002/ccr3.366] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 06/07/2015] [Accepted: 07/25/2015] [Indexed: 11/17/2022] Open
Abstract
We report the first case of pregnancy in a pediatric patient with catecholiminergic polymorphic ventricular tachycardia (CPVT). Pregnant adolescents with CPVT are at high risk for NSVT and malignant VT during pregnancy, despite antiarrhythmic medication. They may receive multiple implantable cardioverter defibrillator (ICD) therapies. Such patients require close monitoring with special care during the first trimester.
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Affiliation(s)
- Aziez Ahmed
- Department of Pediatrics West Virginia University-Charleston Area Medical Center 830 Pennsylvania Avenue Suite 102 Charleston West Virginia 25302
| | - John R Phillips
- Department of Pediatric Cardiology Ruby Memorial Hospital West Virginia University-Morgantown P.O. Box 9214 Morgantown West Virginia 26506
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114
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Koudsi L, Nikolova S, Mishra V. Management of a severe case of Gitelman syndrome with poor response to standard treatment. BMJ Case Rep 2016; 2016:bcr-2015-212375. [PMID: 26887881 DOI: 10.1136/bcr-2015-212375] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Gitelman syndrome is an autosomal recessive distal renal tubular disorder caused by defective sodium chloride transporters. Biochemically, it presents with hypokalaemic metabolic alkalosis, hypomagnesaemia and hypocalciuria. It is usually managed with oral potassium supplements and potassium-sparing diuretics. We report a case of a 28-year-old woman whose condition worsened during pregnancy; she became resistant to standard management after delivery of her second child. She was managed in a specialist metabolic clinic through a comprehensive approach including perseverance with oral potassium supplement, weekly intravenous potassium and magnesium infusion, correction of vitamin D level and the offering of appropriate dietary advice; this controlled the patient's symptoms and prevented repeated hospital admissions. In this case report, we illustrate a patient's presentation and diagnosis with Gitelman syndrome, discuss triggers of exacerbation, review the relevant literature in terms of differential diagnoses and provide practical advice on the management of difficult cases in a specialist clinic.
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Affiliation(s)
- Leila Koudsi
- Department of Clinical Biochemistry, Royal Liverpool and Broadgreen University Hospitals NHS Trust, Liverpool, UK
| | - Stanka Nikolova
- Department of Clinical Biochemistry, Royal Liverpool and Broadgreen University Hospitals NHS Trust, Liverpool, UK
| | - Vinita Mishra
- Department of Clinical Biochemistry, Royal Liverpool and Broadgreen University Hospitals NHS Trust, Liverpool, UK
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115
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Picones A, Loza-Huerta A, Segura-Chama P, Lara-Figueroa CO. Contribution of Automated Technologies to Ion Channel Drug Discovery. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2016; 104:357-378. [DOI: 10.1016/bs.apcsb.2016.01.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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116
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Kumar P, Kumar D, Jha SK, Jha NK, Ambasta RK. Ion Channels in Neurological Disorders. ION CHANNELS AS THERAPEUTIC TARGETS, PART A 2016; 103:97-136. [DOI: 10.1016/bs.apcsb.2015.10.006] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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117
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Abstract
PURPOSE OF REVIEW Recent international expert consensus statements have updated the clinical and genetic diagnoses of patients suffering from arrhythmogenic diseases. However, a lack of genotype-phenotype correlations has hampered the development of a risk stratification scale for sudden cardiac death. RECENT FINDINGS The improvement in the field of genetics has prompted the discovery of new genes associated with sudden cardiac death. Sudden cardiac death is a socially devastating event, especially when it occurs in the pediatric population. Physical activity can often trigger the arrhythmia and sudden death may be the first symptom. These inherited cardiac diseases may be difficult to diagnose, leaving family members also at risk. Thanks to the development of new high-throughput technologies, genetics may be used in the diagnosis of these diseases and even cases that remain unexplained after a comprehensive autopsy. Genetic testing cannot only identify the causative genetic variant in the index case, but it enables the detection of relatives at risk of sudden death, despite remaining clinically asymptomatic. SUMMARY We review the recent advances in the genetics of inherited arrhythmias associated with sudden cardiac death. We focus on the pediatric population, the main group of people suffering from lethal inherited arrhythmias.
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118
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Noh S, Lee SR, Jeong YJ, Ko KS, Rhee BD, Kim N, Han J. The direct modulatory activity of zinc toward ion channels. Integr Med Res 2015; 4:142-146. [PMID: 28664120 PMCID: PMC5481804 DOI: 10.1016/j.imr.2015.07.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 07/08/2015] [Indexed: 12/19/2022] Open
Abstract
The divalent zinc ion is a cation that plays an indispensable role as a structural constituent of numerous proteins, including enzymes and transcription factors. Recently, it has been suggested that zinc also plays a dynamic role in extracellular and intracellular signaling as well. Ion channels are pore-forming proteins that control the flow of specific ions across the membrane, which is important to maintain ion gradients. In this review, we outline the modulatory effect of zinc on the activities of several ion channels through direct binding of zinc into histidine, cysteine, aspartate, and glutamate moieties of channel proteins. The binding of zinc to ion channels results in the activation or inhibition of the channel due to conformational changes. These novel aspects of ion-channel activity modulation by zinc provide new insights into the physiological regulation of ion channels.
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Affiliation(s)
- Sujin Noh
- National Research Laboratory for Mitochondrial Signaling, Department of Physiology, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
| | - Sung Ryul Lee
- National Research Laboratory for Mitochondrial Signaling, Department of Physiology, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
| | - Yu Jeong Jeong
- National Research Laboratory for Mitochondrial Signaling, Department of Physiology, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
| | - Kyung Soo Ko
- National Research Laboratory for Mitochondrial Signaling, Department of Physiology, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
| | - Byoung Doo Rhee
- National Research Laboratory for Mitochondrial Signaling, Department of Physiology, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
| | - Nari Kim
- National Research Laboratory for Mitochondrial Signaling, Department of Physiology, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
| | - Jin Han
- National Research Laboratory for Mitochondrial Signaling, Department of Physiology, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
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Yuan H, Low CM, Moody OA, Jenkins A, Traynelis SF. Ionotropic GABA and Glutamate Receptor Mutations and Human Neurologic Diseases. Mol Pharmacol 2015; 88:203-17. [PMID: 25904555 PMCID: PMC4468639 DOI: 10.1124/mol.115.097998] [Citation(s) in RCA: 153] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 04/22/2015] [Indexed: 01/03/2023] Open
Abstract
The advent of whole exome/genome sequencing and the technology-driven reduction in the cost of next-generation sequencing as well as the introduction of diagnostic-targeted sequencing chips have resulted in an unprecedented volume of data directly linking patient genomic variability to disorders of the brain. This information has the potential to transform our understanding of neurologic disorders by improving diagnoses, illuminating the molecular heterogeneity underlying diseases, and identifying new targets for therapeutic treatment. There is a strong history of mutations in GABA receptor genes being involved in neurologic diseases, particularly the epilepsies. In addition, a substantial number of variants and mutations have been found in GABA receptor genes in patients with autism, schizophrenia, and addiction, suggesting potential links between the GABA receptors and these conditions. A new and unexpected outcome from sequencing efforts has been the surprising number of mutations found in glutamate receptor subunits, with the GRIN2A gene encoding the GluN2A N-methyl-d-aspartate receptor subunit being most often affected. These mutations are associated with multiple neurologic conditions, for which seizure disorders comprise the largest group. The GluN2A subunit appears to be a locus for epilepsy, which holds important therapeutic implications. Virtually all α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor mutations, most of which occur within GRIA3, are from patients with intellectual disabilities, suggesting a link to this condition. Similarly, the most common phenotype for kainate receptor variants is intellectual disability. Herein, we summarize the current understanding of disease-associated mutations in ionotropic GABA and glutamate receptor families, and discuss implications regarding the identification of human mutations and treatment of neurologic diseases.
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Affiliation(s)
- Hongjie Yuan
- Departments of Pharmacology (H.Y., A.J., S.F.T.) and Anesthesiology (O.A.M., A.J.), Emory University School of Medicine, Rollins Research Center, Atlanta, Georgia; and Departments of Pharmacology and Anaesthesia, Yong Loo Lin School of Medicine, National University of Singapore Graduate School for Integrative Sciences and Engineering, and Neurobiology/Ageing Programme, National University of Singapore, Singapore (C.-M.L.)
| | - Chian-Ming Low
- Departments of Pharmacology (H.Y., A.J., S.F.T.) and Anesthesiology (O.A.M., A.J.), Emory University School of Medicine, Rollins Research Center, Atlanta, Georgia; and Departments of Pharmacology and Anaesthesia, Yong Loo Lin School of Medicine, National University of Singapore Graduate School for Integrative Sciences and Engineering, and Neurobiology/Ageing Programme, National University of Singapore, Singapore (C.-M.L.)
| | - Olivia A Moody
- Departments of Pharmacology (H.Y., A.J., S.F.T.) and Anesthesiology (O.A.M., A.J.), Emory University School of Medicine, Rollins Research Center, Atlanta, Georgia; and Departments of Pharmacology and Anaesthesia, Yong Loo Lin School of Medicine, National University of Singapore Graduate School for Integrative Sciences and Engineering, and Neurobiology/Ageing Programme, National University of Singapore, Singapore (C.-M.L.)
| | - Andrew Jenkins
- Departments of Pharmacology (H.Y., A.J., S.F.T.) and Anesthesiology (O.A.M., A.J.), Emory University School of Medicine, Rollins Research Center, Atlanta, Georgia; and Departments of Pharmacology and Anaesthesia, Yong Loo Lin School of Medicine, National University of Singapore Graduate School for Integrative Sciences and Engineering, and Neurobiology/Ageing Programme, National University of Singapore, Singapore (C.-M.L.)
| | - Stephen F Traynelis
- Departments of Pharmacology (H.Y., A.J., S.F.T.) and Anesthesiology (O.A.M., A.J.), Emory University School of Medicine, Rollins Research Center, Atlanta, Georgia; and Departments of Pharmacology and Anaesthesia, Yong Loo Lin School of Medicine, National University of Singapore Graduate School for Integrative Sciences and Engineering, and Neurobiology/Ageing Programme, National University of Singapore, Singapore (C.-M.L.)
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Kim M, McKinnon D, MacCarthy T, Rosati B, McKinnon D. Regulatory evolution and voltage-gated ion channel expression in squid axon: selection-mutation balance and fitness cliffs. PLoS One 2015; 10:e0120785. [PMID: 25875483 PMCID: PMC4395378 DOI: 10.1371/journal.pone.0120785] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 01/27/2015] [Indexed: 11/23/2022] Open
Abstract
It has been suggested that optimization of either axonal conduction velocity or the energy efficiency of action potential conduction predominates in the selection of voltage-gated sodium conductance levels in the squid axon. A population genetics model of channel gene regulatory function was used to examine the role of these and other evolutionary forces on the selection of both sodium and potassium channel expression levels. In this model, the accumulating effects of mutations result in degradation of gene regulatory function, causing channel gene expression to fall to near-zero in the absence of positive selection. In the presence of positive selection, channel expression levels fall to the lowest values consistent with the selection criteria, thereby establishing a selection-mutation balance. Within the parameter space of sodium and potassium conductance values, the physiological performance of the squid axon model showed marked discontinuities associated with conduction failure and excitability. These discontinuities in physiological function may produce fitness cliffs. A fitness cliff associated with conduction failure, combined with the effects of phenotypic noise, can account for the selection of sodium conductance levels, without considering either conduction velocity or metabolic cost. A fitness cliff associated with a transition in axonal excitability, combined with phenotypic noise, can explain the selection of potassium channel expression levels. The results suggest that voltage-gated ion channel expression will fall to low levels, consistent with key functional constraints, even in the absence of positive selection for energy efficiency. Channel expression levels and individual variation in channel expression within the population can be explained by regulatory evolution in combination with genetic variation in regulatory function and phenotypic noise, without resorting to more complex mechanisms, such as activity-dependent homeostasis. Only a relatively small region of the large, nominally isofunctional parameter space for channel expression will normally be occupied, because of the effects of mutation.
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Affiliation(s)
- Min Kim
- Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, New York, United States of America
| | - Don McKinnon
- Institute of Molecular Cardiology, Stony Brook University, Stony Brook, New York, United States of America
| | - Thomas MacCarthy
- Department of Applied Mathematics and Statistics, Stony Brook University, Stony Brook, New York, United States of America
| | - Barbara Rosati
- Institute of Molecular Cardiology, Stony Brook University, Stony Brook, New York, United States of America; Department of Physiology and Biophysics, Stony Brook University, Stony Brook, New York, United States of America
| | - David McKinnon
- Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, New York, United States of America; Institute of Molecular Cardiology, Stony Brook University, Stony Brook, New York, United States of America; The Department of Research, Veterans Affairs Medical Center, Northport, New York, United States of America
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Brignone MS, Lanciotti A, Camerini S, De Nuccio C, Petrucci TC, Visentin S, Ambrosini E. MLC1 protein: a likely link between leukodystrophies and brain channelopathies. Front Cell Neurosci 2015; 9:66. [PMID: 25883547 PMCID: PMC4381631 DOI: 10.3389/fncel.2015.00106] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 03/09/2015] [Indexed: 01/12/2023] Open
Abstract
Megalencephalic leukoencephalopathy with subcortical cysts (MLCs) disease is a rare inherited, autosomal recessive form of childhood-onset spongiform leukodystrophy characterized by macrocephaly, deterioration of motor functions, epileptic seizures and mental decline. Brain edema, subcortical fluid cysts, myelin and astrocyte vacuolation are the histopathological hallmarks of MLC. Mutations in either the MLC1 gene (>75% of patients) or the GlialCAM gene (<20% of patients) are responsible for the disease. Recently, the GlialCAM adhesion protein was found essential for the membrane expression and function of the chloride channel ClC-2 indicating MLC disease caused by mutation in GlialCAM as the first channelopathy among leukodystrophies. On the contrary, the function of MLC1 protein, which binds GlialCAM, its functional relationship with ClC-2 and the molecular mechanisms underlying MLC1 mutation-induced functional defects are not fully understood yet. The human MLC1 gene encodes a 377-amino acid membrane protein with eight predicted transmembrane domains which shows very low homology with voltage-dependent potassium (K+) channel subunits. The high expression of MLC1 in brain astrocytes contacting blood vessels and meninges and brain alterations observed in MLC patients have led to hypothesize a role for MLC1 in the regulation of ion and water homeostasis. Recent studies have shown that MLC1 establishes structural and/or functional interactions with several ion/water channels and transporters and ion channel accessory proteins, and that these interactions are affected by MLC1 mutations causing MLC. Here, we review data on MLC1 functional properties obtained in in vitro and in vivo models and discuss evidence linking the effects of MLC1 mutations to brain channelopathies.
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Affiliation(s)
- Maria S Brignone
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità Rome, Italy
| | - Angela Lanciotti
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità Rome, Italy
| | - Serena Camerini
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità Rome, Italy
| | - Chiara De Nuccio
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità Rome, Italy
| | - Tamara C Petrucci
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità Rome, Italy
| | - Sergio Visentin
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità Rome, Italy
| | - Elena Ambrosini
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità Rome, Italy
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Choquet K, La Piana R, Brais B. A novel frameshift mutation in FGF14 causes an autosomal dominant episodic ataxia. Neurogenetics 2015; 16:233-6. [PMID: 25566820 DOI: 10.1007/s10048-014-0436-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 12/19/2014] [Indexed: 12/30/2022]
Abstract
Episodic ataxias (EAs) are a heterogeneous group of neurological disorders characterized by recurrent attacks of ataxia. Mutations in KCNA1 and CACNA1A account for the majority of EA cases worldwide. We recruited a two-generation family affected with EA of unknown subtype and performed whole-exome sequencing on two affected members. This revealed a novel heterozygous mutation c.211_212insA (p.I71NfsX27) leading to a premature stop codon in FGF14. Mutations in FGF14 are known to cause spinocerebellar ataxia type 27 (SCA27). Sanger sequencing confirmed segregation within the family. Our findings expand the phenotypic spectrum of SCA27 by underlining the possible episodic nature of this ataxia.
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Affiliation(s)
- Karine Choquet
- Neurogenetics of Motion Laboratory, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, H3A 2B4, Canada
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Kim JB, Kim SJ, Kang SY, Yi JW, Kim SM. The large-conductance calcium-activated potassium channel holds the key to the conundrum of familial hypokalemic periodic paralysis. KOREAN JOURNAL OF PEDIATRICS 2014; 57:445-50. [PMID: 25379045 PMCID: PMC4219947 DOI: 10.3345/kjp.2014.57.10.445] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 03/27/2014] [Accepted: 06/03/2014] [Indexed: 11/30/2022]
Abstract
Purpose Familial hypokalemic periodic paralysis (HOKPP) is an autosomal dominant channelopathy characterized by episodic attacks of muscle weakness and hypokalemia. Mutations in the calcium channel gene, CACNA1S, or the sodium channel gene, SCN4A, have been found to be responsible for HOKPP; however, the mechanism that causes hypokalemia remains to be determined. The aim of this study was to improve the understanding of this mechanism by investigating the expression of calcium-activated potassium (KCa) channel genes in HOKPP patients. Methods We measured the intracellular calcium concentration with fura-2-acetoxymethyl ester in skeletal muscle cells of HOKPP patients and healthy individuals. We examined the mRNA and protein expression of KCa channel genes (KCNMA1, KCNN1, KCNN2, KCNN3, and KCNN4) in both cell types. Results Patient cells exhibited higher cytosolic calcium levels than normal cells. Quantitative reverse transcription polymerase chain reaction analysis showed that the mRNA levels of the KCa channel genes did not significantly differ between patient and normal cells. However, western blot analysis showed that protein levels of the KCNMA1 gene, which encodes KCa1.1 channels (also called big potassium channels), were significantly lower in the membrane fraction and higher in the cytosolic fraction of patient cells than normal cells. When patient cells were exposed to 50 mM potassium buffer, which was used to induce depolarization, the altered subcellular distribution of BK channels remained unchanged. Conclusion These findings suggest a novel mechanism for the development of hypokalemia and paralysis in HOKPP and demonstrate a connection between disease-associated mutations in calcium/sodium channels and pathogenic changes in nonmutant potassium channels.
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Affiliation(s)
- June-Bum Kim
- Department of Pediatrics, Hallym University Hangang Sacred Heart Hospital, Seoul, Korea
| | - Sung-Jo Kim
- Department of Biotechnology, Hoseo University, Asan, Korea
| | - Sun-Yang Kang
- Department of Biotechnology, Hoseo University, Asan, Korea
| | - Jin Woong Yi
- Department of Orthopedic Surgery, Konyang University Hospital, Daejeon, Korea
| | - Seung-Min Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Korea
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Partemi S, Vidal MC, Striano P, Campuzano O, Allegue C, Pezzella M, Elia M, Parisi P, Belcastro V, Casellato S, Giordano L, Mastrangelo M, Pietrafusa N, Striano S, Zara F, Bianchi A, Buti D, La Neve A, Tassinari CA, Oliva A, Brugada R. Genetic and forensic implications in epilepsy and cardiac arrhythmias: a case series. Int J Legal Med 2014; 129:495-504. [PMID: 25119684 DOI: 10.1007/s00414-014-1063-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 08/05/2014] [Indexed: 12/27/2022]
Abstract
Epilepsy affects approximately 3% of the world's population, and sudden death is a significant cause of death in this population. Sudden unexpected death in epilepsy (SUDEP) accounts for up to 17% of all these cases, which increases the rate of sudden death by 24-fold as compared to the general population. The underlying mechanisms are still not elucidated, but recent studies suggest the possibility that a common genetic channelopathy might contribute to both epilepsy and cardiac disease to increase the incidence of death via a lethal cardiac arrhythmia. We performed genetic testing in a large cohort of individuals with epilepsy and cardiac conduction disorders in order to identify genetic mutations that could play a role in the mechanism of sudden death. Putative pathogenic disease-causing mutations in genes encoding cardiac ion channel were detected in 24% of unrelated individuals with epilepsy. Segregation analysis through genetic screening of the available family members and functional studies are crucial tasks to understand and to prove the possible pathogenicity of the variant, but in our cohort, only two families were available. Despite further research should be performed to clarify the mechanism of coexistence of both clinical conditions, genetic analysis, applied also in post-mortem setting, could be very useful to identify genetic factors that predispose epileptic patients to sudden death, helping to prevent sudden death in patients with epilepsy.
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Affiliation(s)
- Sara Partemi
- Institute of Legal Medicine, School of Medicine, Catholic University, Rome, Italy
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