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Fogaça-da-Mata M, Martínez-Barrios E, Jiménez-Montañés L, Cruzalegui J, Chipa-Ccasani F, Greco A, Cesar S, Díez-Escuté N, Cerralbo P, Zschaeck I, Clavero Adell M, Ayerza-Casas A, Palanca-Arias D, López M, Campuzano O, Brugada J, Sarquella-Brugada G. Brugada Syndrome and Pulmonary Atresia with Intact Interventricular Septum: Fortuitous Finding or New Genetic Connection? Genes (Basel) 2024; 15:638. [PMID: 38790267 PMCID: PMC11121103 DOI: 10.3390/genes15050638] [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: 04/01/2024] [Revised: 05/15/2024] [Accepted: 05/16/2024] [Indexed: 05/26/2024] Open
Abstract
Brugada syndrome is a rare arrhythmogenic syndrome associated mainly with pathogenic variants in the SCN5A gene. Right ventricle outflow tract fibrosis has been reported in some cases of patients diagnosed with Brugada syndrome. Pulmonary atresia with an intact ventricular septum is characterized by the lack of a functional pulmonary valve, due to the underdevelopment of the right ventricle outflow tract. We report, for the first time, a 4-year-old boy with pulmonary atresia with an intact ventricular septum who harbored a pathogenic de novo variant in SCN5A, and the ajmaline test unmasked a type-1 Brugada pattern. We suggest that deleterious variants in the SCN5A gene could be implicated in pulmonary atresia with an intact ventricular septum embryogenesis, leading to overlapping phenotypes.
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Affiliation(s)
- Miguel Fogaça-da-Mata
- Arrhythmia, Inherited Cardiac Diseases and Sudden Death Unit, Hospital Sant Joan de Déu, Passeig Sant Joan de Déu 2, Esplugues de Llobregat, 08950 Barcelona, Spain; (M.F.-d.-M.); (E.M.-B.); (J.C.); (F.C.-C.); (A.G.); (S.C.); (N.D.-E.); (P.C.); (I.Z.)
- Pediatric Cardiology Unit, Hospital de Santa Cruz, Centro Hospitalar Lisboa Ocidental, 1449-005 Lisbon, Portugal
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart (ERN GUARD-Heart), 1105 AZ Amsterdam, The Netherlands
| | - Estefanía Martínez-Barrios
- Arrhythmia, Inherited Cardiac Diseases and Sudden Death Unit, Hospital Sant Joan de Déu, Passeig Sant Joan de Déu 2, Esplugues de Llobregat, 08950 Barcelona, Spain; (M.F.-d.-M.); (E.M.-B.); (J.C.); (F.C.-C.); (A.G.); (S.C.); (N.D.-E.); (P.C.); (I.Z.)
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart (ERN GUARD-Heart), 1105 AZ Amsterdam, The Netherlands
- Arrítmies Pediàtriques, Cardiologia Genètica i Mort Sobtada, Institut de Recerca Sant Joan de Déu, Santa Rosa 39–57, Esplugues de Llobregat, 08950 Barcelona, Spain
- Medical Science Department, School of Medicine, Universitat de Girona, 17003 Girona, Spain;
| | - Lorenzo Jiménez-Montañés
- Pediatric Cardiology Unit, University Hospital Miguel Servet, 50009 Zaragoza, Spain; (L.J.-M.); (M.C.A.); (A.A.-C.); (D.P.-A.); (M.L.)
| | - José Cruzalegui
- Arrhythmia, Inherited Cardiac Diseases and Sudden Death Unit, Hospital Sant Joan de Déu, Passeig Sant Joan de Déu 2, Esplugues de Llobregat, 08950 Barcelona, Spain; (M.F.-d.-M.); (E.M.-B.); (J.C.); (F.C.-C.); (A.G.); (S.C.); (N.D.-E.); (P.C.); (I.Z.)
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart (ERN GUARD-Heart), 1105 AZ Amsterdam, The Netherlands
- Arrítmies Pediàtriques, Cardiologia Genètica i Mort Sobtada, Institut de Recerca Sant Joan de Déu, Santa Rosa 39–57, Esplugues de Llobregat, 08950 Barcelona, Spain
| | - Fredy Chipa-Ccasani
- Arrhythmia, Inherited Cardiac Diseases and Sudden Death Unit, Hospital Sant Joan de Déu, Passeig Sant Joan de Déu 2, Esplugues de Llobregat, 08950 Barcelona, Spain; (M.F.-d.-M.); (E.M.-B.); (J.C.); (F.C.-C.); (A.G.); (S.C.); (N.D.-E.); (P.C.); (I.Z.)
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart (ERN GUARD-Heart), 1105 AZ Amsterdam, The Netherlands
- Arrítmies Pediàtriques, Cardiologia Genètica i Mort Sobtada, Institut de Recerca Sant Joan de Déu, Santa Rosa 39–57, Esplugues de Llobregat, 08950 Barcelona, Spain
| | - Andrea Greco
- Arrhythmia, Inherited Cardiac Diseases and Sudden Death Unit, Hospital Sant Joan de Déu, Passeig Sant Joan de Déu 2, Esplugues de Llobregat, 08950 Barcelona, Spain; (M.F.-d.-M.); (E.M.-B.); (J.C.); (F.C.-C.); (A.G.); (S.C.); (N.D.-E.); (P.C.); (I.Z.)
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart (ERN GUARD-Heart), 1105 AZ Amsterdam, The Netherlands
- Arrítmies Pediàtriques, Cardiologia Genètica i Mort Sobtada, Institut de Recerca Sant Joan de Déu, Santa Rosa 39–57, Esplugues de Llobregat, 08950 Barcelona, Spain
| | - Sergi Cesar
- Arrhythmia, Inherited Cardiac Diseases and Sudden Death Unit, Hospital Sant Joan de Déu, Passeig Sant Joan de Déu 2, Esplugues de Llobregat, 08950 Barcelona, Spain; (M.F.-d.-M.); (E.M.-B.); (J.C.); (F.C.-C.); (A.G.); (S.C.); (N.D.-E.); (P.C.); (I.Z.)
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart (ERN GUARD-Heart), 1105 AZ Amsterdam, The Netherlands
- Arrítmies Pediàtriques, Cardiologia Genètica i Mort Sobtada, Institut de Recerca Sant Joan de Déu, Santa Rosa 39–57, Esplugues de Llobregat, 08950 Barcelona, Spain
| | - Núria Díez-Escuté
- Arrhythmia, Inherited Cardiac Diseases and Sudden Death Unit, Hospital Sant Joan de Déu, Passeig Sant Joan de Déu 2, Esplugues de Llobregat, 08950 Barcelona, Spain; (M.F.-d.-M.); (E.M.-B.); (J.C.); (F.C.-C.); (A.G.); (S.C.); (N.D.-E.); (P.C.); (I.Z.)
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart (ERN GUARD-Heart), 1105 AZ Amsterdam, The Netherlands
- Arrítmies Pediàtriques, Cardiologia Genètica i Mort Sobtada, Institut de Recerca Sant Joan de Déu, Santa Rosa 39–57, Esplugues de Llobregat, 08950 Barcelona, Spain
| | - Patricia Cerralbo
- Arrhythmia, Inherited Cardiac Diseases and Sudden Death Unit, Hospital Sant Joan de Déu, Passeig Sant Joan de Déu 2, Esplugues de Llobregat, 08950 Barcelona, Spain; (M.F.-d.-M.); (E.M.-B.); (J.C.); (F.C.-C.); (A.G.); (S.C.); (N.D.-E.); (P.C.); (I.Z.)
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart (ERN GUARD-Heart), 1105 AZ Amsterdam, The Netherlands
- Arrítmies Pediàtriques, Cardiologia Genètica i Mort Sobtada, Institut de Recerca Sant Joan de Déu, Santa Rosa 39–57, Esplugues de Llobregat, 08950 Barcelona, Spain
| | - Irene Zschaeck
- Arrhythmia, Inherited Cardiac Diseases and Sudden Death Unit, Hospital Sant Joan de Déu, Passeig Sant Joan de Déu 2, Esplugues de Llobregat, 08950 Barcelona, Spain; (M.F.-d.-M.); (E.M.-B.); (J.C.); (F.C.-C.); (A.G.); (S.C.); (N.D.-E.); (P.C.); (I.Z.)
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart (ERN GUARD-Heart), 1105 AZ Amsterdam, The Netherlands
- Arrítmies Pediàtriques, Cardiologia Genètica i Mort Sobtada, Institut de Recerca Sant Joan de Déu, Santa Rosa 39–57, Esplugues de Llobregat, 08950 Barcelona, Spain
| | - Marcos Clavero Adell
- Pediatric Cardiology Unit, University Hospital Miguel Servet, 50009 Zaragoza, Spain; (L.J.-M.); (M.C.A.); (A.A.-C.); (D.P.-A.); (M.L.)
| | - Ariadna Ayerza-Casas
- Pediatric Cardiology Unit, University Hospital Miguel Servet, 50009 Zaragoza, Spain; (L.J.-M.); (M.C.A.); (A.A.-C.); (D.P.-A.); (M.L.)
| | - Daniel Palanca-Arias
- Pediatric Cardiology Unit, University Hospital Miguel Servet, 50009 Zaragoza, Spain; (L.J.-M.); (M.C.A.); (A.A.-C.); (D.P.-A.); (M.L.)
| | - Marta López
- Pediatric Cardiology Unit, University Hospital Miguel Servet, 50009 Zaragoza, Spain; (L.J.-M.); (M.C.A.); (A.A.-C.); (D.P.-A.); (M.L.)
| | - Oscar Campuzano
- Medical Science Department, School of Medicine, Universitat de Girona, 17003 Girona, Spain;
- Centro de Investigación Biomédica en Red, Enfermedades Cardiovasculares, 28029 Madrid, Spain;
- Cardiovascular Genetics Center, University of Girona—IDIBGI, 17190 Girona, Spain
| | - Josep Brugada
- Centro de Investigación Biomédica en Red, Enfermedades Cardiovasculares, 28029 Madrid, Spain;
- Arrhythmias Unit, Hospital Clinic de Barcelona, Universitat de Barcelona, 08036 Barcelona, Spain
| | - Georgia Sarquella-Brugada
- Arrhythmia, Inherited Cardiac Diseases and Sudden Death Unit, Hospital Sant Joan de Déu, Passeig Sant Joan de Déu 2, Esplugues de Llobregat, 08950 Barcelona, Spain; (M.F.-d.-M.); (E.M.-B.); (J.C.); (F.C.-C.); (A.G.); (S.C.); (N.D.-E.); (P.C.); (I.Z.)
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart (ERN GUARD-Heart), 1105 AZ Amsterdam, The Netherlands
- Arrítmies Pediàtriques, Cardiologia Genètica i Mort Sobtada, Institut de Recerca Sant Joan de Déu, Santa Rosa 39–57, Esplugues de Llobregat, 08950 Barcelona, Spain
- Medical Science Department, School of Medicine, Universitat de Girona, 17003 Girona, Spain;
- Department of Surgery and Medico-Surgical Specialties, School of Medicine and Health Sciences, Universitat de Barcelona, 08036 Barcelona, Spain
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Zhang ZH, Barajas-Martinez H, Jiang H, Huang CX, Antzelevitch C, Xia H, Hu D. Gene and stem cell therapy for inherited cardiac arrhythmias. Pharmacol Ther 2024; 256:108596. [PMID: 38301770 DOI: 10.1016/j.pharmthera.2024.108596] [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: 09/26/2023] [Revised: 12/11/2023] [Accepted: 01/13/2024] [Indexed: 02/03/2024]
Abstract
Inherited cardiac arrhythmias are a group of genetic diseases predisposing to sudden cardiac arrest, mainly resulting from variants in genes encoding cardiac ion channels or proteins involved in their regulation. Currently available therapeutic options (pharmacotherapy, ablative therapy and device-based therapy) can not preclude the occurrence of arrhythmia events and/or provide complete protection. With growing understanding of the genetic background and molecular mechanisms of inherited cardiac arrhythmias, advancing insight of stem cell technology, and development of vectors and delivery strategies, gene therapy and stem cell therapy may be promising approaches for treatment of inherited cardiac arrhythmias. Recent years have witnessed impressive progress in the basic science aspects and there is a clear and urgent need to be translated into the clinical management of arrhythmic events. In this review, we present a succinct overview of gene and cell therapy strategies, and summarize the current status of gene and cell therapy. Finally, we discuss future directions for implementation of gene and cell therapy in the therapy of inherited cardiac arrhythmias.
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Affiliation(s)
- Zhong-He Zhang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan, 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan, 430060, PR China
| | - Hector Barajas-Martinez
- Lankenau Institute for Medical Research, Lankenau Heart Institute, Wynnwood, PA, 19096, USA; Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Hong Jiang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan, 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan, 430060, PR China
| | - Cong-Xin Huang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan, 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan, 430060, PR China
| | - Charles Antzelevitch
- Lankenau Institute for Medical Research, Lankenau Heart Institute, Wynnwood, PA, 19096, USA; Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Hao Xia
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan, 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan, 430060, PR China.
| | - Dan Hu
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan, 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan, 430060, PR China.
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Zhang Z, Chen H, Chen W, Zhang Z, Li R, Xu J, Yang C, Chen M, Liu S, Li Y, Wang T, Tu X, Huang Z. Genetic Characteristics and Transcriptional Regulation of Sodium Channel Related Genes in Chinese Patients With Brugada Syndrome. Front Cardiovasc Med 2021; 8:714844. [PMID: 34422936 PMCID: PMC8374431 DOI: 10.3389/fcvm.2021.714844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 07/05/2021] [Indexed: 11/13/2022] Open
Abstract
Objective: To investigate the genetic characteristics and transcriptional regulation of the SCN5A gene of Brugada syndrome (BrS) patients in China. Methods: Using PubMed, Medline, China National Knowledge Internet (CNKI), and Wanfang Database, Chinese patients with BrS who underwent SCN5A gene testing were studied. Results: A total of 27 suitable studies involving Chinese BrS patients who underwent the SCN5A gene test were included. A total of 55 SCN5A gene mutations/variations were reported in Chinese BrS patients, including 10 from southern China and 45 from northern China. Mutations/variations of BrS patients from southern China mostly occurred in the regions of the α-subunit of Nav1.5, including DIII (Domain III), DIV, DIII-DIV, C-terminus regions, and the 3'UTR region. Furthermore, we analyzed the post-transcriptional modifications (PTMs) throughout the Nav1.5 protein encoded by SCN5A and found that the PTM changes happened in 72.7% of BrS patients from southern China and 26.7% from northern China. Conclusions: SCN5A mutations/variations of BrS patients in southern China mostly occurred in the DIII-DIV to C-terminus region and the 3'-UTR region of the SCN5A gene, different from northern China. PTM changes were consistent with the mutation/variation distribution of SCN5A, which might be involved in the regulation of the pathogenesis of BrS patients.
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Affiliation(s)
- Ziguan Zhang
- Department of Cardiology, Xiamen Key Laboratory of Cardiac Electrophysiology, Xiamen Institute of Cardiovascular Diseases, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Hongwei Chen
- Department of Cardiology, Xiamen Key Laboratory of Cardiac Electrophysiology, Xiamen Institute of Cardiovascular Diseases, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Wenbo Chen
- Department of Cardiology, Xiamen Key Laboratory of Cardiac Electrophysiology, Xiamen Institute of Cardiovascular Diseases, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Zhenghao Zhang
- Department of Cardiology, Xiamen Key Laboratory of Cardiac Electrophysiology, Xiamen Institute of Cardiovascular Diseases, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Runjing Li
- Department of Cardiology, Xiamen Key Laboratory of Cardiac Electrophysiology, Xiamen Institute of Cardiovascular Diseases, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Jiajia Xu
- Department of Cardiology, Xiamen Key Laboratory of Cardiac Electrophysiology, Xiamen Institute of Cardiovascular Diseases, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Cui Yang
- Department of Cardiology, Xiamen Key Laboratory of Cardiac Electrophysiology, Xiamen Institute of Cardiovascular Diseases, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Minwei Chen
- Department of Cardiology, Xiamen Key Laboratory of Cardiac Electrophysiology, Xiamen Institute of Cardiovascular Diseases, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Shixiao Liu
- Department of Cardiology, Xiamen Key Laboratory of Cardiac Electrophysiology, Xiamen Institute of Cardiovascular Diseases, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Yanling Li
- Department of Cardiology, Xiamen Key Laboratory of Cardiac Electrophysiology, Xiamen Institute of Cardiovascular Diseases, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - TzungDau Wang
- Department of Internal Medicine, Cardiovascular Center and Division of Cardiology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, China
| | - Xin Tu
- Cardio-X Center, Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology and Center for Human Genome Research, Huazhong University of Science and Technology, Wuhan, China
| | - Zhengrong Huang
- Department of Cardiology, Xiamen Key Laboratory of Cardiac Electrophysiology, Xiamen Institute of Cardiovascular Diseases, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
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Dong C, Wang Y, Ma A, Wang T. Life Cycle of the Cardiac Voltage-Gated Sodium Channel Na V1.5. Front Physiol 2020; 11:609733. [PMID: 33391024 PMCID: PMC7773603 DOI: 10.3389/fphys.2020.609733] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 11/12/2020] [Indexed: 12/13/2022] Open
Abstract
Cardiac voltage-gated sodium channel NaV1.5, encoded by SCN5A, is crucial for the upstroke of action potential and excitation of cardiomyocytes. NaV1.5 undergoes complex processes before it reaches the target membrane microdomains and performs normal functions. A variety of protein partners are needed to achieve the balance between SCN5A transcription and mRNA decay, endoplasmic reticulum retention and export, Golgi apparatus retention and export, selective anchoring and degradation, activation, and inactivation of sodium currents. Subtle alterations can impair NaV1.5 in terms of expression or function, eventually leading to NaV1.5-associated diseases such as lethal arrhythmias and cardiomyopathy.
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Affiliation(s)
- Caijuan Dong
- Department of Cardiovascular Medicine, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Ya Wang
- Department of Cardiovascular Medicine, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Aiqun Ma
- Department of Cardiovascular Medicine, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Key Laboratory of Molecular Cardiology, Shaanxi Province, Xi'an, China.,Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education, Xi'an, China
| | - Tingzhong Wang
- Department of Cardiovascular Medicine, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Key Laboratory of Molecular Cardiology, Shaanxi Province, Xi'an, China.,Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education, Xi'an, China
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Van Malderen SCH, Daneels D, Kerkhove D, Peeters U, Theuns DAMJ, Droogmans S, Van Camp G, Weytjens C, Biervliet M, Bonduelle M, Van Dooren S, Brugada P. Prolonged Right Ventricular Ejection Delay in Brugada Syndrome Depends on the Type of SCN5A Variant - Electromechanical Coupling Through Tissue Velocity Imaging as a Bridge Between Genotyping and Phenotyping. Circ J 2017; 82:53-61. [PMID: 28781330 DOI: 10.1253/circj.cj-16-1279] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Patients with Brugada syndrome (BrS) and a history of syncope or sustained ventricular arrhythmia have longer right ventricular ejection delays (RVEDs) than asymptomatic BrS patients. Different types ofSCN5Avariants leading to different reductions in sodium current (INa) may have different effects on conduction delay, and consequently on electromechanical coupling (i.e., RVED). Thus, we investigated the genotype-phenotype relationship by measuring RVED to establish whether BrS patients carrying more severeSCN5Avariants leading to premature protein truncation (T) and presumably 100%INareduction have a longer RVED than patients carrying missense variants (M) with different degrees ofINareduction.Methods and Results:There were 34 BrS patients (mean [±SD] age 43.3±12.9 years; 52.9% male) carrying anSCN5Avariant and 66 non-carriers in this cross-sectional study. Patients carrying aSCN5Avariant were divided into T-carriers (n=13) and M-carriers (n=21). Using tissue velocity imaging, RVED and left ventricular ejection delay (LVED) were measured as the time from QRS onset to the onset of the systolic ejection wave at the end of the isovolumetric contraction. T-carriers had longer RVEDs than M-carriers (139.3±15.1 vs. 124.8±11.9 ms, respectively; P=0.008) and non-carriers (127.7±17.3 ms, P=0.027). There were no differences in LVED among groups. CONCLUSIONS Using the simple, non-invasive echocardiographic parameter RVED revealed a more pronounced 'electromechanical' delay in BrS patients carrying T variants ofSCN5A.
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Affiliation(s)
- Sophie C H Van Malderen
- Department of Electrophysiology (Heart Rhythm Management Centre), Vrije Universiteit Brussel, UZ Brussel.,Department of Cardiology, AZ Nikolaas.,Department of Electrophysiology, Thorax Centre, Erasmus MC
| | - Dorien Daneels
- Centre for Medical Genetics, Reproduction and Genetics, Reproduction Genetics and Regenerative Medicine, Vrije Universiteit Brussel, UZ Brussel
| | - Dirk Kerkhove
- Department of Non-invasive Cardiology, Vrije Universiteit Brussel, UZ Brussel
| | - Uschi Peeters
- Centre for Medical Genetics, Reproduction and Genetics, Reproduction Genetics and Regenerative Medicine, Vrije Universiteit Brussel, UZ Brussel
| | | | - Steven Droogmans
- Department of Non-invasive Cardiology, Vrije Universiteit Brussel, UZ Brussel
| | - Guy Van Camp
- Department of Non-invasive Cardiology, Vrije Universiteit Brussel, UZ Brussel
| | - Caroline Weytjens
- Department of Non-invasive Cardiology, Vrije Universiteit Brussel, UZ Brussel
| | - Martine Biervliet
- Centre for Medical Genetics, Reproduction and Genetics, Reproduction Genetics and Regenerative Medicine, Vrije Universiteit Brussel, UZ Brussel
| | - Maryse Bonduelle
- Centre for Medical Genetics, Reproduction and Genetics, Reproduction Genetics and Regenerative Medicine, Vrije Universiteit Brussel, UZ Brussel
| | - Sonia Van Dooren
- Centre for Medical Genetics, Reproduction and Genetics, Reproduction Genetics and Regenerative Medicine, Vrije Universiteit Brussel, UZ Brussel
| | - Pedro Brugada
- Department of Electrophysiology (Heart Rhythm Management Centre), Vrije Universiteit Brussel, UZ Brussel
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Harmer SC, Tinker A. The impact of recent advances in genetics in understanding disease mechanisms underlying the long QT syndromes. Biol Chem 2017; 397:679-93. [PMID: 26910742 DOI: 10.1515/hsz-2015-0306] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 02/18/2016] [Indexed: 11/15/2022]
Abstract
Long QT syndrome refers to a characteristic abnormality of the electrocardiogram and it is associated with a form of ventricular tachycardia known as torsade-de-pointes and sudden arrhythmic death. It can occur as part of a hereditary syndrome or can be acquired usually because of drug administration. Here we review recent genetic, molecular and cellular discoveries and outline how they have furthered our understanding of this disease. Specifically we focus on compound mutations, genome wide association studies of QT interval, modifier genes and the therapeutic implications of this recent work.
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Kosmidis G, Veerman CC, Casini S, Verkerk AO, van de Pas S, Bellin M, Wilde AAM, Mummery CL, Bezzina CR. Readthrough-Promoting Drugs Gentamicin and PTC124 Fail to Rescue Nav1.5 Function of Human-Induced Pluripotent Stem Cell-Derived Cardiomyocytes Carrying Nonsense Mutations in the Sodium Channel Gene SCN5A. Circ Arrhythm Electrophysiol 2017; 9:CIRCEP.116.004227. [PMID: 27784737 DOI: 10.1161/circep.116.004227] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 09/09/2016] [Indexed: 11/16/2022]
Abstract
BACKGROUND Several compounds have been reported to induce translational readthrough of premature stop codons resulting in the production of full-length protein by interfering with ribosomal proofreading. Here we examined the effect of 2 of these compounds, gentamicin and PTC124, in human-induced pluripotent stem cell (hiPSC)-derived cardiomyocytes bearing nonsense mutations in the sodium channel gene SCN5A, which are associated with conduction disease and potential lethal arrhythmias. METHODS AND RESULTS We generated hiPSC from 2 patients carrying the mutations R1638X and W156X. hiPSC-derived cardiomyocytes from both patients recapitulated the expected electrophysiological phenotype, as evidenced by reduced Na+ currents and action potential upstroke velocities compared with hiPSC-derived cardiomyocytes from 2 unrelated control individuals. While we were able to confirm the readthrough efficacy of the 2 drugs in Human Embryonic Kidney 293 cells, we did not observe rescue of the electrophysiological phenotype in hiPSC-derived cardiomyocytes from the patients. CONCLUSIONS We conclude that these drugs are unlikely to present an effective treatment for patients carrying the loss-of-function SCN5A gene mutations examined in this study.
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Affiliation(s)
- Georgios Kosmidis
- From the Department of Anatomy and Embryology, Leiden University Medical Center, Leiden (G.K., S.C., S.v.d.P., M.B., C.L.M.); and Heart Center, Department of Experimental and Clinical Cardiology (C.C.V., A.A.M.W., C.R.B.) and Department of Anatomy and Embryology, Academic Medical Center (A.O.V.), Amsterdam, The Netherlands
| | - Christiaan C Veerman
- From the Department of Anatomy and Embryology, Leiden University Medical Center, Leiden (G.K., S.C., S.v.d.P., M.B., C.L.M.); and Heart Center, Department of Experimental and Clinical Cardiology (C.C.V., A.A.M.W., C.R.B.) and Department of Anatomy and Embryology, Academic Medical Center (A.O.V.), Amsterdam, The Netherlands
| | - Simona Casini
- From the Department of Anatomy and Embryology, Leiden University Medical Center, Leiden (G.K., S.C., S.v.d.P., M.B., C.L.M.); and Heart Center, Department of Experimental and Clinical Cardiology (C.C.V., A.A.M.W., C.R.B.) and Department of Anatomy and Embryology, Academic Medical Center (A.O.V.), Amsterdam, The Netherlands
| | - Arie O Verkerk
- From the Department of Anatomy and Embryology, Leiden University Medical Center, Leiden (G.K., S.C., S.v.d.P., M.B., C.L.M.); and Heart Center, Department of Experimental and Clinical Cardiology (C.C.V., A.A.M.W., C.R.B.) and Department of Anatomy and Embryology, Academic Medical Center (A.O.V.), Amsterdam, The Netherlands
| | - Simone van de Pas
- From the Department of Anatomy and Embryology, Leiden University Medical Center, Leiden (G.K., S.C., S.v.d.P., M.B., C.L.M.); and Heart Center, Department of Experimental and Clinical Cardiology (C.C.V., A.A.M.W., C.R.B.) and Department of Anatomy and Embryology, Academic Medical Center (A.O.V.), Amsterdam, The Netherlands
| | - Milena Bellin
- From the Department of Anatomy and Embryology, Leiden University Medical Center, Leiden (G.K., S.C., S.v.d.P., M.B., C.L.M.); and Heart Center, Department of Experimental and Clinical Cardiology (C.C.V., A.A.M.W., C.R.B.) and Department of Anatomy and Embryology, Academic Medical Center (A.O.V.), Amsterdam, The Netherlands
| | - Arthur A M Wilde
- From the Department of Anatomy and Embryology, Leiden University Medical Center, Leiden (G.K., S.C., S.v.d.P., M.B., C.L.M.); and Heart Center, Department of Experimental and Clinical Cardiology (C.C.V., A.A.M.W., C.R.B.) and Department of Anatomy and Embryology, Academic Medical Center (A.O.V.), Amsterdam, The Netherlands
| | - Christine L Mummery
- From the Department of Anatomy and Embryology, Leiden University Medical Center, Leiden (G.K., S.C., S.v.d.P., M.B., C.L.M.); and Heart Center, Department of Experimental and Clinical Cardiology (C.C.V., A.A.M.W., C.R.B.) and Department of Anatomy and Embryology, Academic Medical Center (A.O.V.), Amsterdam, The Netherlands
| | - Connie R Bezzina
- From the Department of Anatomy and Embryology, Leiden University Medical Center, Leiden (G.K., S.C., S.v.d.P., M.B., C.L.M.); and Heart Center, Department of Experimental and Clinical Cardiology (C.C.V., A.A.M.W., C.R.B.) and Department of Anatomy and Embryology, Academic Medical Center (A.O.V.), Amsterdam, The Netherlands.
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8
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Liu Z, Shan H, Huang J, Li N, Hou C, Pu J. A novel lamin A/C gene missense mutation (445 V > E) in immunoglobulin-like fold associated with left ventricular non-compaction. Europace 2016; 18:617-622. [PMID: 25829471 DOI: 10.1093/europace/euv044] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 02/08/2015] [Indexed: 01/22/2024] Open
Abstract
AIMS Two LMNA mutations (R644C and R190W) have been associated with familial and sporadic left ventricular non-compaction (LVNC). However, the mechanisms underlying these associations have not been elucidated. METHODS AND RESULTS Genomic DNA was isolated from peripheral blood leucocytes and analysed by direct sequencing. Human embryonic kidney 293 cells were transfected with either wild type or mutant LMNA and SCN5A for whole-cell patch-clamp experiment and fluorescence microscopy. Point mutation modeling for mutant LMNA was also performed. One novel LVNC-associated mutation (V445E) in β2 sheet of immunoglobulin (Ig)-like fold was found in the proband and his father. We also found that the peak current of sodium channel was markedly reduced in mutant LMNA compared with WT while the activation, inactivation, and recovery curves were not significantly altered. The mutant lamin A/C were aggregated into multiple highlighted particles. Three β sheets and multiple side chains in Ig-like fold were altered due to the replacement of a valine by glutamic acid. CONCLUSION Our data associated a novel lamin A/C mutation (V445E) with a sudden death form of familial LVNC. The reduced sodium current in mutant LMNA may account for the advent of malignant ventricular arrhythmias. The altered structures of three β sheets and side chains may partially explain the aggregation of lamin A/C protein subjacent to the nuclear envelope.
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MESH Headings
- Adolescent
- DNA Mutational Analysis
- Death, Sudden, Cardiac/etiology
- Echocardiography
- Electrocardiography
- Genetic Predisposition to Disease
- Glutamic Acid
- HEK293 Cells
- Heterozygote
- Humans
- Isolated Noncompaction of the Ventricular Myocardium/diagnosis
- Isolated Noncompaction of the Ventricular Myocardium/genetics
- Isolated Noncompaction of the Ventricular Myocardium/metabolism
- Isolated Noncompaction of the Ventricular Myocardium/physiopathology
- Lamin Type A/chemistry
- Lamin Type A/genetics
- Lamin Type A/metabolism
- Male
- Membrane Potentials
- Microscopy, Fluorescence
- Models, Molecular
- Mutagenesis, Site-Directed
- Mutation, Missense
- Phenotype
- Protein Aggregates
- Protein Conformation, beta-Strand
- Protein Folding
- Structure-Activity Relationship
- Tachycardia, Ventricular/diagnosis
- Tachycardia, Ventricular/genetics
- Tachycardia, Ventricular/metabolism
- Tachycardia, Ventricular/physiopathology
- Transfection
- Valine
- Ventricular Fibrillation/diagnosis
- Ventricular Fibrillation/genetics
- Ventricular Fibrillation/metabolism
- Ventricular Fibrillation/physiopathology
- Young Adult
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Affiliation(s)
- Zhouying Liu
- State Key Laboratory of Cardiovascular Disease, Physiology and Pathophysiology Laboratory, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, 167 Bei-Li-Shi Road, Xi-Cheng District, Beijing 100037, P.R. China
| | - Hong Shan
- Department of Biophysics, School of Basic Medical Sciences, Peking University, 38 Xue-Yuan Road, Hai-Dian District, Beijing 100191, P.R. China
| | - Jian Huang
- State Key Laboratory of Cardiovascular Disease, Physiology and Pathophysiology Laboratory, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, 167 Bei-Li-Shi Road, Xi-Cheng District, Beijing 100037, P.R. China
| | - Ning Li
- State Key Laboratory of Cardiovascular Disease, Physiology and Pathophysiology Laboratory, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, 167 Bei-Li-Shi Road, Xi-Cheng District, Beijing 100037, P.R. China
| | - Cuihong Hou
- State Key Laboratory of Cardiovascular Disease, Physiology and Pathophysiology Laboratory, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, 167 Bei-Li-Shi Road, Xi-Cheng District, Beijing 100037, P.R. China
| | - Jielin Pu
- State Key Laboratory of Cardiovascular Disease, Physiology and Pathophysiology Laboratory, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, 167 Bei-Li-Shi Road, Xi-Cheng District, Beijing 100037, P.R. China
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9
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Guo Q, Ren L, Chen X, Hou C, Chu J, Pu J, Zhang S. A novel mutation in the SCN5A gene contributes to arrhythmogenic characteristics of early repolarization syndrome. Int J Mol Med 2016; 37:727-33. [PMID: 26820605 PMCID: PMC4771109 DOI: 10.3892/ijmm.2016.2468] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 01/13/2016] [Indexed: 12/17/2022] Open
Abstract
Several genetic variants have been associated with early repolarization syndrome (ERS). However, the lack of functional validations of the mutant effects has limited the interpretation of genetic tests. In the present study, we identified and characterized a novel sodium channel, voltage gated, type V alpha subunit (SCN5A) mutation that was associated with ERS. A 67-year-old male proband suffering from recurrent syncope underwent a documented electrocardiogram (ECG) for polymorphic ventricular tachycardia (VT). It was noted that baseline 12-lead ECG exhibited a predominantly elevated ST-segment which mimicked acute myocardial ischemia in lead V2-V6, and the ECG also demonstrated J waves in lead Ⅱ, Ⅲ, aVF and V2-V6. Using genetic analysis, we noted that the proband carried a novel heterozygous missense mutation of A1055G in the SCN5A gene. Whole-cell configuration of patch-clamp analysis revealed that the mutation significantly decreased peak sodium current (INa) density and shifted the steady-state inactivation curve of INa to a more negative potential. Confocal imaging suggested that in the mutant channel a defect of protein expression both on the cell membrane and in cytoplasm was present. The present study demonstrated that a novel heterozygous missense mutation of A1055G in SCN5A led to 'loss-of function' of the sodium channels, and we suggest that it accounts for the arrhythmogenic characteristics of ERS.
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Affiliation(s)
- Qi Guo
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, P.R. China
| | - Lan Ren
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, P.R. China
| | - Xuhua Chen
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, P.R. China
| | - Cuihong Hou
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, P.R. China
| | - Jianmin Chu
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, P.R. China
| | - Jielin Pu
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, P.R. China
| | - Shu Zhang
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, P.R. China
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10
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Ruwald MH, Xu Parks X, Moss AJ, Zareba W, Baman J, McNitt S, Kanters JK, Shimizu W, Wilde AA, Jons C, Lopes CM. Stop-codon and C-terminal nonsense mutations are associated with a lower risk of cardiac events in patients with long QT syndrome type 1. Heart Rhythm 2015; 13:122-31. [PMID: 26318259 DOI: 10.1016/j.hrthm.2015.08.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Indexed: 10/23/2022]
Abstract
BACKGROUND In long QT syndrome type 1 (LQT1), the location and type of mutations have been shown to affect the clinical outcome. Although haploinsufficiency, including stop-codon and frameshift mutations, has been associated with a lower risk of cardiac events in patients with LQT1, nonsense mutations have been presumed functionally equivalent. OBJECTIVE The purpose of this study was to evaluate clinical differences between patients with nonsense mutations. METHODS The study sample comprised 1090 patients with genetically confirmed mutations. Patients were categorized into 5 groups, depending on mutation type and location: missense not located in the high-risk cytoplasmic loop (c-loop) (n = 698), which is used as reference; missense c-loop (n = 192); stop-codon (n = 67); frameshift (n = 39); and others (n = 94). The primary outcome was a composite end point of syncope, aborted cardiac arrest, and long QT syndrome-related death (cardiac events). Outcomes were evaluated using the multivariate Cox proportional hazards regression analysis. Standard patch clamp techniques were used. RESULTS Compared to patients with missense non-c-loop mutations, the risk of cardiac events was reduced significantly in patients with stop-codon mutations (hazard ratio [HR] 0.57; 95% confidence interval [CI] 0.34-0.96; P = .035), but not in patients with frameshift mutations (HR 1.01; 95% CI 0.58-1.77; P = .97). Our data suggest that currents of the most common stop-codon mutant channel (Q530X) were larger than those of haploinsufficient channels (wild type: 42 ± 6 pA/pF, n = 20; Q530X+wild type: 79 ± 14 pA/pF, n = 20; P < .05) and voltage dependence of activation was altered. CONCLUSION Stop-codon mutations are associated with a lower risk of cardiac events in patients with LQT1, while frameshift mutations are associated with the same risk as the majority of the missense mutations. Our data indicate functional differences between these previously considered equivalent mutation subtypes.
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Affiliation(s)
- Martin H Ruwald
- Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, Rochester, New York; Department of Cardiology, Gentofte Hospital, Hellerup, Denmark
| | - Xiaorong Xu Parks
- Cardiovascular Research Institute, Department of Medicine, University of Rochester, Rochester, New York
| | - Arthur J Moss
- Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, Rochester, New York
| | - Wojciech Zareba
- Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, Rochester, New York
| | - Jayson Baman
- Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, Rochester, New York
| | - Scott McNitt
- Heart Research Follow-up Program, Division of Cardiology, University of Rochester Medical Center, Rochester, New York
| | - Jorgen K Kanters
- Department of Cardiology, Gentofte Hospital, Hellerup, Denmark; Laboratory of Experimental Cardiology, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Wataru Shimizu
- Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan
| | - Arthur A Wilde
- AMC Heart Centre, Department of Clinical and Experimental Cardiology, Academic Medical Centre, Amsterdam, The Netherlands
| | - Christian Jons
- Department of Cardiology, Gentofte Hospital, Hellerup, Denmark
| | - Coeli M Lopes
- Cardiovascular Research Institute, Department of Medicine, University of Rochester, Rochester, New York.
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11
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Abstract
Brugada syndrome is an inherited arrhythmia syndrome predisposing to sudden cardiac death. Six years after its initial description as a clinical entity, the first mutations in SCN5A encoding the cardiac sodium channel Nav1.5 were reported. Over 300 mutations in SCN5A have since been described in addition to mutations in genes encoding Nav1.5 auxiliary units, potassium and calcium channels. This review summarizes the current knowledge on the genetics of Brugada syndrome, focusing on SCN5A, and discusses its use as a biomarker for diagnosis, prognosis and treatment.
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Affiliation(s)
- Anthony Li
- Cardiovascular Sciences Research Centre, St George’s University of London, Cranmer Terrace, London, SW17 0RE, UK
| | - Magdi M Saba
- Cardiovascular Sciences Research Centre, St George’s University of London, Cranmer Terrace, London, SW17 0RE, UK
| | - Elijah R Behr
- Cardiovascular Sciences Research Centre, St George’s University of London, Cranmer Terrace, London, SW17 0RE, UK.
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12
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Nielsen MW, Holst AG, Olesen SP, Olesen MS. The genetic component of Brugada syndrome. Front Physiol 2013; 4:179. [PMID: 23874304 PMCID: PMC3710955 DOI: 10.3389/fphys.2013.00179] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 06/24/2013] [Indexed: 12/12/2022] Open
Abstract
Brugada syndrome (BrS) is a clinical entity first described in 1992. BrS is characterized by ST-segment elevations in the right precordial leads and susceptibility to ventricular arrhythmias and sudden cardiac death. It affects young subjects, predominantly males, with structurally normal hearts. The prevalence varies with ethnicity ranging from 1:2,000 to 1:100,000 in different parts of the world. Today, hundreds of variants in 17 genes have been associated with BrS of which mutations in SCN5A, coding for the cardiac voltage-gated sodium channel, accounts for the vast majority. Despite this, approximately 70% of BrS cases cannot be explained genetically with the current knowledge. Moreover, the monogenic role of some of the variants previously described as being associated with BrS has been questioned by their occurrence in about 4% (1:23) of the general population as found in NHLBI GO Exome Sequencing Project (ESP) currently including approximately 6500 individuals. If we add the variants described in the five newest identified genes associated with BrS, they appear at an even higher prevalence in the ESP (1:21). The current standard treatment of BrS is an implantable cardioverter-defibrillator (ICD). The risk stratification and indications for ICD treatment are based on the ECG and on the clinical and family history. In this review we discuss the genetic basis of BrS.
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Affiliation(s)
- Morten W Nielsen
- The Danish National Research Foundation Centre for Cardiac Arrhythmia Copenhagen, Denmark ; Department of Cardiology, Laboratory for Molecular Cardiology, The Heart Centre, Rigshospitalet, University of Copenhagen Copenhagen, Denmark
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13
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LI NING, WANG RONGRONG, HOU CUIHONG, ZHANG YINHUI, TENG SIYONG, PU JIELIN. A heterozygous missense SCN5A mutation associated with early repolarization syndrome. Int J Mol Med 2013; 32:661-7. [PMID: 23799537 DOI: 10.3892/ijmm.2013.1422] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Accepted: 09/10/2012] [Indexed: 11/06/2022] Open
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14
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Novel SCN5A mutations in two families with "Brugada-like" ST elevation in the inferior leads and conduction disturbances. J Interv Card Electrophysiol 2013; 37:131-40. [PMID: 23612926 DOI: 10.1007/s10840-013-9805-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2012] [Accepted: 03/20/2013] [Indexed: 10/26/2022]
Abstract
AIMS Brugada syndrome (BrS) is an inherited cardiac disease characterized by ST segment elevation in V1-V3 ECG leads. Mutations SCN5A gene encoding for the cardiac voltage-gated Na(+) channel are found in some BrS patients, but also in family members with isolated conduction disturbances. However, some patients show coved ST elevation in the inferior or lateral leads whose association with SCN5A and familial conduction disturbances are poorly known. METHODS AND RESULTS Two novel SCN5A mutations, D1430N and Q1476X, were identified in two unrelated families comprising patients with Brugada-like ST elevation located in the inferior leads or isolated conduction disturbances. Wild-type (WT) and D1430N mutant channels were expressed in tsA201 cells. Patch clamp electrophysiological experiments revealed total absence of Na(+) current resulting from Nav1.5 mutant when compared to WT channels. Treatments known to restore trafficking defect (incubation at low temperature, with mexiletine or lidocaine) did not restore Na(+) current supporting that Nav1.5 mutation is not a defective trafficking mutation. Furthermore, immunocytolabelling indicates the membrane localisation of both WT and mutant channels confirming what we observed in our patch clamp experiments. This suggests that the mutation may induce a complete block of Na(+) permeation. The nonsense mutation Q1476X was leading to a premature stop codon and was not expressed. CONCLUSION Brugada-like ST elevation in the inferior ECG leads or isolated conduction disturbances were found in two unrelated families and associated with two novel SCN5A mutations. The missense and nonsense mutations are both resulting in a complete loss of ventricular Na(+) current explaining the phenotypes.
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15
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Bébarová M. Arrhythmogenesis in Brugada syndrome: impact and constrains of current concepts. Int J Cardiol 2013; 167:1760-71. [PMID: 23295036 DOI: 10.1016/j.ijcard.2012.12.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 11/15/2012] [Accepted: 12/06/2012] [Indexed: 01/13/2023]
Abstract
Brugada syndrome (BrS), an inherited arrhythmogenic disease first described in 1992, is characterized by ST segment elevations on the electrocardiogram in the right precordium and by a high occurrence of arrhythmias including the life-threatening ventricular tachycardia/fibrillation. Knowledge of the underlying mechanisms of formation of arrhythmogenic substrate in BrS is essential, namely for the risk stratification of BrS patients and their therapy which is still restrained almost exclusively to the implantation of cardioverter/defibrillator. In spite of many crucial findings in this field published within recent years, the final consistent view has not been established so far. Hence, BrS described 20 years ago remains an actual topic of both clinical and experimental studies. This review presents an overview of the current knowledge related to the pathogenesis of BrS arrhythmogenic substrate, namely of the genetic basis of BrS, functional consequences of mutations related to BrS, and arrhythmogenic mechanisms in BrS.
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Affiliation(s)
- Markéta Bébarová
- Department of Physiology, Faculty of Medicine, Masaryk University, Kamenice 5, 625 00 Brno, Bohunice, Czech Republic.
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16
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Eckhardt LL. Phenotype, genotype, and cellular physiology: Need for clarity in characterization. Heart Rhythm 2012; 9:1993-4. [DOI: 10.1016/j.hrthm.2012.08.033] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2012] [Indexed: 11/27/2022]
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17
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Bordeira-Carriço R, Pêgo AP, Santos M, Oliveira C. Cancer syndromes and therapy by stop-codon readthrough. Trends Mol Med 2012; 18:667-78. [PMID: 23044248 DOI: 10.1016/j.molmed.2012.09.004] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2012] [Revised: 08/10/2012] [Accepted: 09/17/2012] [Indexed: 12/19/2022]
Abstract
Several hereditary cancer syndromes are associated with nonsense mutations that create premature termination codons (PTC). Therapeutic strategies involving readthrough induction partially restore expression of proteins with normal function from nonsense-mutated genes, and small molecules such as aminoglycosides and PTC124 have exhibited promising results for treating patients with cystic fibrosis and Duchenne muscular dystrophy. Transgenic expression of suppressor-tRNAs and depleting translation termination factors are, among others, potential strategies for treating PTC-associated diseases. In this review, the potential of using readthrough strategies as a therapy for cancer syndromes is discussed, and we consider the effect of nonsense-mediated decay and other factors on readthrough efficiency.
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18
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Park DS, Fishman GI. Forever young: induced pluripotent stem cells as models of inherited arrhythmias. Circulation 2012; 125:3055-6. [PMID: 22647977 DOI: 10.1161/circulationaha.112.114165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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19
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The chemical compound PTC124 does not affect cellular electrophysiology of cardiac ventricular myocytes. Cardiovasc Drugs Ther 2012; 26:41-5. [PMID: 22065308 DOI: 10.1007/s10557-011-6352-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
PURPOSE Nonsense mutations that create premature termination codons (PTC) leading to disease by a mechanism of haploinsufficiency are relatively common in the SCN5A gene encoding the major sodium channel in heart. PTCs in SCN5A are associated with isolated conduction disease and Brugada syndrome (BrS). Pharmacological therapy does not exist for these disorders, but would be highly beneficial. Recently, an orally bio-available drug capable of suppressing premature termination, PTC124, has been identified that selectively induces ribosomal read-through of premature but not normal termination codons. In this study, we tested the acute and long-term effects of PTC124 on action potential characteristics of rabbit ventricular cardiomyocytes. METHODS The effects of PTC124 on action potentials of isolated adult rabbit ventricular cardiomyocytes were studied using the perforated patch-clamp methodology. Acute effects of PTC124 were measured in freshly isolated cardiomyocytes, while long term effects were measured after 48 h in cultured cardiomyocytes. RESULTS Resting membrane potential, maximum upstroke velocity, action potential amplitude and action potential duration at 20, 50 and 90% of repolarization were not affected by application of PTC124, neither acute nor after 48 h. CONCLUSION PTC124 has no acute or long-term effects on rabbit ventricular action potentials. These experiments form the basis for future studies evaluating the use of this therapy in preventing potentially lethal arrhythmias in patients with BrS and/or conduction disease.
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20
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Lubos E, Loscalzo J, Handy DE. Glutathione peroxidase-1 in health and disease: from molecular mechanisms to therapeutic opportunities. Antioxid Redox Signal 2011; 15:1957-97. [PMID: 21087145 PMCID: PMC3159114 DOI: 10.1089/ars.2010.3586] [Citation(s) in RCA: 740] [Impact Index Per Article: 56.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Reactive oxygen species, such as superoxide and hydrogen peroxide, are generated in all cells by mitochondrial and enzymatic sources. Left unchecked, these reactive species can cause oxidative damage to DNA, proteins, and membrane lipids. Glutathione peroxidase-1 (GPx-1) is an intracellular antioxidant enzyme that enzymatically reduces hydrogen peroxide to water to limit its harmful effects. Certain reactive oxygen species, such as hydrogen peroxide, are also essential for growth factor-mediated signal transduction, mitochondrial function, and maintenance of normal thiol redox-balance. Thus, by limiting hydrogen peroxide accumulation, GPx-1 also modulates these processes. This review explores the molecular mechanisms involved in regulating the expression and function of GPx-1, with an emphasis on the role of GPx-1 in modulating cellular oxidant stress and redox-mediated responses. As a selenocysteine-containing enzyme, GPx-1 expression is subject to unique forms of regulation involving the trace mineral selenium and selenocysteine incorporation during translation. In addition, GPx-1 has been implicated in the development and prevention of many common and complex diseases, including cancer and cardiovascular disease. This review discusses the role of GPx-1 in these diseases and speculates on potential future therapies to harness the beneficial effects of this ubiquitous antioxidant enzyme.
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Affiliation(s)
- Edith Lubos
- Department of Medicine II, University Medical Center, Johannes Gutenberg-University, Mainz, Germany
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21
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Schulze-Bahr E. Making sense in a nonsense reading frame: suppression of cardiac sodium channel dysfunction. Cardiovasc Res 2009; 83:423-4. [PMID: 19528082 DOI: 10.1093/cvr/cvp196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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