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Padda I, Sebastian SA, Khehra N, Mahtani A, Sethi Y, Panthangi V, Fulton M, Bandyopadhyay D, Johal G. Tachy-brady syndrome: Electrophysiology and evolving principles of management. Dis Mon 2024; 70:101637. [PMID: 37690863 DOI: 10.1016/j.disamonth.2023.101637] [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] [Indexed: 09/12/2023]
Abstract
Sudden alterations in the heart rate may be associated with diverse symptoms. Sinus node dysfunction (SND), also known as sick sinus syndrome, is a sinoatrial (SA) node disorder. SND is primarily caused by the dysfunction of the pacemaker, as well as impaired impulse transmission resulting in a multitude of abnormalities in the heart rhythms, such as bradycardia-tachycardia, atrial bradyarrhythmias, and atrial tachyarrhythmias. The transition from bradycardia to tachycardia is generally referred to as "tachy-brady syndrome" (TBS). Although TBS is etiologically variable, the manifestations remain consistent throughout. Abnormal heart rhythms have the propensity to limit tissue perfusion resulting in palpitations, fatigue, lightheadedness, presyncope, and syncope. In this review, we examine the physiology of tachy-brady syndrome, the practical approach to its diagnosis and management, and the role of adenosine in treating SND.
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Affiliation(s)
- Inderbir Padda
- Department of Internal Medicine, Richmond University Medical Center/Mount Sinai, Staten Island, NY, USA.
| | | | - Nimrat Khehra
- Saint James School of Medicine, Arnos Vale, Saint Vincent and the Grenadines
| | - Arun Mahtani
- Department of Internal Medicine, Richmond University Medical Center/Mount Sinai, Staten Island, NY, USA
| | - Yashendra Sethi
- Department of Internal Medicine, Government Doon Medical College, Dehradun, India
| | | | - Matthew Fulton
- Department of Internal Medicine, Richmond University Medical Center/Mount Sinai, Staten Island, NY, USA
| | | | - Gurpreet Johal
- Department of Cardiology, University of Washington, Valley Medical Center, Seattle, WA, USA
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Ferrand MC, Giordano G, Mougenot N, Laporte PL, Vignier N, Leclerc A, Algalarrondo V, Extramiana F, Charpentier F, Neyroud N. Intracardiac electrophysiology to characterize susceptibility to ventricular arrhythmias in murine models. Front Physiol 2024; 15:1326663. [PMID: 38322613 PMCID: PMC10846502 DOI: 10.3389/fphys.2024.1326663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 01/08/2024] [Indexed: 02/08/2024] Open
Abstract
Introduction: Sudden cardiac death (SCD) and ventricular fibrillation are rare but severe complications of many cardiovascular diseases and represent a major health issue worldwide. Although the primary causes are often acute or chronic coronary diseases, genetic conditions, such as inherited channelopathies or non-ischemic cardiomyopathies are leading causes of SCD among the young. However, relevant experimental models to study the underlying mechanisms of arrhythmias and develop new therapies are still needed. The number of genetically engineered mouse models with cardiac phenotype is growing, making electrophysiological studies in mice essential tools to study arrhythmogenicity and arrhythmia mechanisms and to test novel treatments. Recently, intracardiac catheterization via the jugular vein was described to induce and record ventricular arrhythmias in living anesthetized mice. Several strategies have been reported, developed in healthy wild-type animals and based on aggressive right ventricular stimulation. Methods: Here, we report a protocol based on programmed electrical stimulation (PES) performed in clinical practice in patients with cardiac rhythm disorders, adapted to two transgenic mice models of arrhythmia - Brugada syndrome and cardiolaminopathy. Results: We show that this progressive protocol, based on a limited number of right ventricular extrastimuli, enables to reveal different rhythmic phenotypes between control and diseased mice. In this study, we provide detailed information on PES in mice, including catheter positioning, stimulation protocols, intracardiac and surface ECG interpretation and we reveal a higher susceptibility of two mouse lines to experience triggered ventricular arrhythmias, when compared to control mice. Discussion: Overall, this technique allows to characterize arrhythmias and provides results in phenotyping 2 arrhythmogenic-disease murine models.
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Affiliation(s)
- Marine C. Ferrand
- Sorbonne Université, Inserm, Research Unit on Cardiovascular and Metabolic Diseases, UMRS-1166, Paris, France
| | - Gauthier Giordano
- Sorbonne Université, Inserm, Research Unit on Cardiovascular and Metabolic Diseases, UMRS-1166, Paris, France
- Competence Center for Hereditary or Rare Heart Diseases, Centre Hospitalier Régional Universitaire de Nancy, Vandœuvre-lès-Nancy, France
| | | | - Pierre-Léo Laporte
- Sorbonne Université, Inserm, Research Unit on Cardiovascular and Metabolic Diseases, UMRS-1166, Paris, France
- Reference Center for Inherited Arrhythmic Syndromes, Hôpital Bichat, APHP, Université de Paris Cité, Paris, France
| | - Nicolas Vignier
- Sorbonne Université, Inserm, UMRS-974, Center of Research in Myology, Institute of Myology, Paris, France
| | - Arnaud Leclerc
- Sorbonne Université, Inserm, Research Unit on Cardiovascular and Metabolic Diseases, UMRS-1166, Paris, France
| | - Vincent Algalarrondo
- Reference Center for Inherited Arrhythmic Syndromes, Hôpital Bichat, APHP, Université de Paris Cité, Paris, France
| | - Fabrice Extramiana
- Sorbonne Université, Inserm, Research Unit on Cardiovascular and Metabolic Diseases, UMRS-1166, Paris, France
- Reference Center for Inherited Arrhythmic Syndromes, Hôpital Bichat, APHP, Université de Paris Cité, Paris, France
| | | | - Nathalie Neyroud
- Sorbonne Université, Inserm, Research Unit on Cardiovascular and Metabolic Diseases, UMRS-1166, Paris, France
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Mesirca P, Chemin J, Barrère C, Torre E, Gallot L, Monteil A, Bidaud I, Diochot S, Lazdunski M, Soong TW, Barrère-Lemaire S, Mangoni ME, Nargeot J. Selective blockade of Ca v1.2 (α1C) versus Ca v1.3 (α1D) L-type calcium channels by the black mamba toxin calciseptine. Nat Commun 2024; 15:54. [PMID: 38167790 PMCID: PMC10762068 DOI: 10.1038/s41467-023-43502-w] [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: 04/21/2023] [Accepted: 11/10/2023] [Indexed: 01/05/2024] Open
Abstract
L-type voltage-gated calcium channels are involved in multiple physiological functions. Currently available antagonists do not discriminate between L-type channel isoforms. Importantly, no selective blocker is available to dissect the role of L-type isoforms Cav1.2 and Cav1.3 that are concomitantly co-expressed in the heart, neuroendocrine and neuronal cells. Here we show that calciseptine, a snake toxin purified from mamba venom, selectively blocks Cav1.2 -mediated L-type calcium currents (ICaL) at concentrations leaving Cav1.3-mediated ICaL unaffected in both native cardiac myocytes and HEK-293T cells expressing recombinant Cav1.2 and Cav1.3 channels. Functionally, calciseptine potently inhibits cardiac contraction without altering the pacemaker activity in sino-atrial node cells, underscoring differential roles of Cav1.2- and Cav1.3 in cardiac contractility and automaticity. In summary, calciseptine is a selective L-type Cav1.2 Ca2+ channel blocker and should be a valuable tool to dissect the role of these L-channel isoforms.
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Affiliation(s)
- Pietro Mesirca
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094, Montpellier, France.
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France.
| | - Jean Chemin
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094, Montpellier, France
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
| | - Christian Barrère
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094, Montpellier, France
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
| | - Eleonora Torre
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094, Montpellier, France
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
| | - Laura Gallot
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094, Montpellier, France
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
| | - Arnaud Monteil
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094, Montpellier, France
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
- Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Isabelle Bidaud
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094, Montpellier, France
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
| | - Sylvie Diochot
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
- Université Côte d'Azur, CNRS, IPMC (Institut de Pharmacologie Moléculaire et Cellulaire), FHU InovPain (Fédération Hospitalo-Universitaire "Innovative Solutions in Refractory Chronic Pain"), F-06560, Valbonne, France
| | - Michel Lazdunski
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
- Université Côte d'Azur, CNRS, IPMC (Institut de Pharmacologie Moléculaire et Cellulaire), FHU InovPain (Fédération Hospitalo-Universitaire "Innovative Solutions in Refractory Chronic Pain"), F-06560, Valbonne, France
| | - Tuck Wah Soong
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Stéphanie Barrère-Lemaire
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094, Montpellier, France
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
| | - Matteo E Mangoni
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094, Montpellier, France
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
| | - Joël Nargeot
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34094, Montpellier, France.
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France.
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Delgado-Betancourt V, Chinda K, Mesirca P, Barrère C, Covinhes A, Gallot L, Vincent A, Bidaud I, Kumphune S, Nargeot J, Piot C, Wickman K, Mangoni ME, Barrère-Lemaire S. Heart rate reduction after genetic ablation of L-type Ca v1.3 channels induces cardioprotection against ischemia-reperfusion injury. Front Cardiovasc Med 2023; 10:1134503. [PMID: 37593151 PMCID: PMC10429177 DOI: 10.3389/fcvm.2023.1134503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Accepted: 06/21/2023] [Indexed: 08/19/2023] Open
Abstract
Background Acute myocardial infarction (AMI) is the major cause of cardiovascular mortality worldwide. Most ischemic episodes are triggered by an increase in heart rate, which induces an imbalance between myocardial oxygen delivery and consumption. Developing drugs that selectively reduce heart rate by inhibiting ion channels involved in heart rate control could provide more clinical benefits. The Cav1.3-mediated L-type Ca2+ current (ICav1.3) play important roles in the generation of heart rate. Therefore, they can constitute relevant targets for selective control of heart rate and cardioprotection during AMI. Objective We aimed to investigate the relationship between heart rate and infarct size using mouse strains knockout for Cav1.3 (Cav1.3-/-) L-type calcium channel and of the cardiac G protein gated potassium channel (Girk4-/-) in association with the funny (f)-channel inhibitor ivabradine. Methods Wild-type (WT), Cav1.3+/-, Cav1.3-/- and Girk4-/- mice were used as models of respectively normal heart rate, moderate heart rate reduction, bradycardia, and mild tachycardia, respectively. Mice underwent a surgical protocol of myocardial IR (40 min ischemia and 60 min reperfusion). Heart rate was recorded by one-lead surface ECG recording, and infarct size measured by triphenyl tetrazolium chloride staining. In addition, Cav1.3-/- and WT hearts perfused on a Langendorff system were subjected to the same ischemia-reperfusion protocol ex vivo, without or with atrial pacing, and the coronary flow was recorded. Results Cav1.3-/- mice presented reduced infarct size (-29%), while Girk4-/- displayed increased infarct size (+30%) compared to WT mice. Consistently, heart rate reduction in Cav1.3+/- or by the f-channel blocker ivabradine was associated with significant decrease in infarct size (-27% and -32%, respectively) in comparison to WT mice. Conclusion Our results show that decreasing heart rate allows to protect the myocardium against IR injury in vivo and reveal a close relationship between basal heart rate and IR injury. In addition, this study suggests that targeting Cav1.3 channels could constitute a relevant target for reducing infarct size, since maximal heart rate dependent cardioprotective effect is already observed in Cav1.3+/- mice.
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Affiliation(s)
- Viviana Delgado-Betancourt
- Institut de Génomique Fonctionnelle, Université Montpellier, CNRS, INSERM, Montpellier, France
- LabEx Ion Channel Science & Therapeutics (ICST), Université de Nice, Valbonne, France
| | - Kroekkiat Chinda
- Institut de Génomique Fonctionnelle, Université Montpellier, CNRS, INSERM, Montpellier, France
- Department of Physiology, Faculty of Medical Science, Naresuan University, Phitsanulok, Thailand
| | - Pietro Mesirca
- Institut de Génomique Fonctionnelle, Université Montpellier, CNRS, INSERM, Montpellier, France
- LabEx Ion Channel Science & Therapeutics (ICST), Université de Nice, Valbonne, France
| | - Christian Barrère
- Institut de Génomique Fonctionnelle, Université Montpellier, CNRS, INSERM, Montpellier, France
- LabEx Ion Channel Science & Therapeutics (ICST), Université de Nice, Valbonne, France
| | - Aurélie Covinhes
- Institut de Génomique Fonctionnelle, Université Montpellier, CNRS, INSERM, Montpellier, France
- LabEx Ion Channel Science & Therapeutics (ICST), Université de Nice, Valbonne, France
| | - Laura Gallot
- Institut de Génomique Fonctionnelle, Université Montpellier, CNRS, INSERM, Montpellier, France
- LabEx Ion Channel Science & Therapeutics (ICST), Université de Nice, Valbonne, France
| | - Anne Vincent
- Institut de Génomique Fonctionnelle, Université Montpellier, CNRS, INSERM, Montpellier, France
- LabEx Ion Channel Science & Therapeutics (ICST), Université de Nice, Valbonne, France
| | - Isabelle Bidaud
- Institut de Génomique Fonctionnelle, Université Montpellier, CNRS, INSERM, Montpellier, France
- LabEx Ion Channel Science & Therapeutics (ICST), Université de Nice, Valbonne, France
| | - Sarawut Kumphune
- Biomedical Engineering Institute (BMEi), Chiang Mai University, Chiang Mai, Thailand
| | - Joël Nargeot
- Institut de Génomique Fonctionnelle, Université Montpellier, CNRS, INSERM, Montpellier, France
- LabEx Ion Channel Science & Therapeutics (ICST), Université de Nice, Valbonne, France
| | - Christophe Piot
- Institut de Génomique Fonctionnelle, Université Montpellier, CNRS, INSERM, Montpellier, France
- LabEx Ion Channel Science & Therapeutics (ICST), Université de Nice, Valbonne, France
- Département de Cardiologie Interventionnelle, Clinique du Millénaire, Montpellier, France
| | - Kevin Wickman
- Department of Pharmacology, University of Minnesota, Minneapolis, MN, United States
| | - Matteo Elia Mangoni
- Institut de Génomique Fonctionnelle, Université Montpellier, CNRS, INSERM, Montpellier, France
- LabEx Ion Channel Science & Therapeutics (ICST), Université de Nice, Valbonne, France
| | - Stéphanie Barrère-Lemaire
- Institut de Génomique Fonctionnelle, Université Montpellier, CNRS, INSERM, Montpellier, France
- LabEx Ion Channel Science & Therapeutics (ICST), Université de Nice, Valbonne, France
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5
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Meyer KM, Malhotra N, Kwak JS, El Refaey M. Relevance of KCNJ5 in Pathologies of Heart Disease. Int J Mol Sci 2023; 24:10849. [PMID: 37446026 PMCID: PMC10341679 DOI: 10.3390/ijms241310849] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 06/16/2023] [Accepted: 06/21/2023] [Indexed: 07/15/2023] Open
Abstract
Abnormalities in G-protein-gated inwardly rectifying potassium (GIRK) channels have been implicated in diseased states of the cardiovascular system; however, the role of GIRK4 (Kir3.4) in cardiac physiology and pathophysiology has yet to be completely understood. Within the heart, the KACh channel, consisting of two GIRK1 and two GIRK4 subunits, plays a major role in modulating the parasympathetic nervous system's influence on cardiac physiology. Being that GIRK4 is necessary for the functional KACh channel, KCNJ5, which encodes GIRK4, it presents as a therapeutic target for cardiovascular pathology. Human variants in KCNJ5 have been identified in familial hyperaldosteronism type III, long QT syndrome, atrial fibrillation, and sinus node dysfunction. Here, we explore the relevance of KCNJ5 in each of these diseases. Further, we address the limitations and complexities of discerning the role of KCNJ5 in cardiovascular pathophysiology, as identical human variants of KCNJ5 have been identified in several diseases with overlapping pathophysiology.
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Affiliation(s)
- Karisa M. Meyer
- Department of Surgery, Division of Cardiac Surgery, The Ohio State University, Columbus, OH 43210, USA; (K.M.M.); (N.M.); (J.s.K.)
- The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA
| | - Nipun Malhotra
- Department of Surgery, Division of Cardiac Surgery, The Ohio State University, Columbus, OH 43210, USA; (K.M.M.); (N.M.); (J.s.K.)
- The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA
| | - Jung seo Kwak
- Department of Surgery, Division of Cardiac Surgery, The Ohio State University, Columbus, OH 43210, USA; (K.M.M.); (N.M.); (J.s.K.)
- The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA
| | - Mona El Refaey
- Department of Surgery, Division of Cardiac Surgery, The Ohio State University, Columbus, OH 43210, USA; (K.M.M.); (N.M.); (J.s.K.)
- The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA
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Wilson C, Zi M, Smith M, Hussain M, D’Souza A, Dobrzynski H, Boyett MR. Atrioventricular node dysfunction in pressure overload-induced heart failure—Involvement of the immune system and transcriptomic remodelling. Front Pharmacol 2023; 14:1083910. [PMID: 37081960 PMCID: PMC10110994 DOI: 10.3389/fphar.2023.1083910] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Accepted: 03/13/2023] [Indexed: 04/07/2023] Open
Abstract
Heart failure is associated with atrioventricular (AV) node dysfunction, and AV node dysfunction in the setting of heart failure is associated with an increased risk of mortality and heart failure hospitalisation. This study aims to understand the causes of AV node dysfunction in heart failure by studying changes in the whole nodal transcriptome. The mouse transverse aortic constriction model of pressure overload-induced heart failure was studied; functional changes were assessed using electrocardiography and echocardiography and the transcriptome of the AV node was quantified using RNAseq. Heart failure was associated with a significant increase in the PR interval, indicating a slowing of AV node conduction and AV node dysfunction, and significant changes in 3,077 transcripts (5.6% of the transcriptome). Many systems were affected: transcripts supporting AV node conduction were downregulated and there were changes in transcripts identified by GWAS as determinants of the PR interval. In addition, there was evidence of remodelling of the sarcomere, a shift from fatty acid to glucose metabolism, remodelling of the extracellular matrix, and remodelling of the transcription and translation machinery. There was evidence of the causes of this widespread remodelling of the AV node: evidence of dysregulation of multiple intracellular signalling pathways, dysregulation of 109 protein kinases and 148 transcription factors, and an immune response with a proliferation of neutrophils, monocytes, macrophages and B lymphocytes and a dysregulation of 40 cytokines. In conclusion, inflammation and a widespread transcriptional remodelling of the AV node underlies AV node dysfunction in heart failure.
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Affiliation(s)
- Claire Wilson
- Division of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Min Zi
- Division of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom
| | - Matthew Smith
- Division of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom
| | - Munir Hussain
- Faculty of Life Sciences, University of Bradford, Bradford, United Kingdom
| | - Alicia D’Souza
- Division of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom
| | - Halina Dobrzynski
- Division of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom
- Department of Anatomy, Jagiellonian University Medical College, Kraków, Poland
- *Correspondence: Halina Dobrzynski, ; Mark R. Boyett,
| | - Mark R. Boyett
- Faculty of Life Sciences, University of Bradford, Bradford, United Kingdom
- *Correspondence: Halina Dobrzynski, ; Mark R. Boyett,
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Characterization of sinoatrial automaticity in Microcebus murinus to study the effect of aging on cardiac activity and the correlation with longevity. Sci Rep 2023; 13:3054. [PMID: 36810863 PMCID: PMC9944915 DOI: 10.1038/s41598-023-29723-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 02/09/2023] [Indexed: 02/24/2023] Open
Abstract
Microcebus murinus, or gray mouse lemur (GML), is one of the smallest primates known, with a size in between mice and rats. The small size, genetic proximity to humans and prolonged senescence, make this lemur an emerging model for neurodegenerative diseases. For the same reasons, it could help understand how aging affects cardiac activity. Here, we provide the first characterization of sinoatrial (SAN) pacemaker activity and of the effect of aging on GML heart rate (HR). According to GML size, its heartbeat and intrinsic pacemaker frequencies lie in between those of mice and rats. To sustain this fast automaticity the GML SAN expresses funny and Ca2+ currents (If, ICa,L and ICa,T) at densities similar to that of small rodents. SAN automaticity was also responsive to β-adrenergic and cholinergic pharmacological stimulation, showing a consequent shift in the localization of the origin of pacemaker activity. We found that aging causes decrease of basal HR and atrial remodeling in GML. We also estimated that, over 12 years of a lifetime, GML generates about 3 billion heartbeats, thus, as many as humans and three times more than rodents of equivalent size. In addition, we estimated that the high number of heartbeats per lifetime is a characteristic that distinguishes primates from rodents or other eutherian mammals, independently from body size. Thus, cardiac endurance could contribute to the exceptional longevity of GML and other primates, suggesting that GML's heart sustains a workload comparable to that of humans in a lifetime. In conclusion, despite the fast HR, GML replicates some of the cardiac deficiencies reported in old people, providing a suitable model to study heart rhythm impairment in aging. Moreover, we estimated that, along with humans and other primates, GML presents a remarkable cardiac longevity, enabling longer life span than other mammals of equivalent size.
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8
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Zaveri S, Srivastava U, Qu YS, Chahine M, Boutjdir M. Pathophysiology of Ca v1.3 L-type calcium channels in the heart. Front Physiol 2023; 14:1144069. [PMID: 37025382 PMCID: PMC10070707 DOI: 10.3389/fphys.2023.1144069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 03/07/2023] [Indexed: 04/08/2023] Open
Abstract
Ca2+ plays a crucial role in excitation-contraction coupling in cardiac myocytes. Dysfunctional Ca2+ regulation alters the force of contraction and causes cardiac arrhythmias. Ca2+ entry into cardiomyocytes is mediated mainly through L-type Ca2+ channels, leading to the subsequent Ca2+ release from the sarcoplasmic reticulum. L-type Ca2+ channels are composed of the conventional Cav1.2, ubiquitously expressed in all heart chambers, and the developmentally regulated Cav1.3, exclusively expressed in the atria, sinoatrial node, and atrioventricular node in the adult heart. As such, Cav1.3 is implicated in the pathogenesis of sinoatrial and atrioventricular node dysfunction as well as atrial fibrillation. More recently, Cav1.3 de novo expression was suggested in heart failure. Here, we review the functional role, expression levels, and regulation of Cav1.3 in the heart, including in the context of cardiac diseases. We believe that the elucidation of the functional and molecular pathways regulating Cav1.3 in the heart will assist in developing novel targeted therapeutic interventions for the aforementioned arrhythmias.
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Affiliation(s)
- Sahil Zaveri
- Cardiovascular Research Program, VA New York Harbor Healthcare System, New York, NY, United States
- Department of Medicine, Cell Biology and Pharmacology, State University of New York Downstate Health Sciences University, Brooklyn, New York, NY, United States
| | - Ujala Srivastava
- Cardiovascular Research Program, VA New York Harbor Healthcare System, New York, NY, United States
| | - Yongxia Sarah Qu
- Cardiovascular Research Program, VA New York Harbor Healthcare System, New York, NY, United States
- Department of Medicine, Cell Biology and Pharmacology, State University of New York Downstate Health Sciences University, Brooklyn, New York, NY, United States
- Department of Cardiology, New York Presbyterian Brooklyn Methodist Hospital, New York, NY, United States
| | - Mohamed Chahine
- CERVO Brain Research Center, Institut Universitaire en Santé Mentale de Québec, Québec, QC, Canada
- Department of Medicine, Faculté de Médecine, Université Laval, Quebec, QC, Canada
| | - Mohamed Boutjdir
- Cardiovascular Research Program, VA New York Harbor Healthcare System, New York, NY, United States
- Department of Medicine, Cell Biology and Pharmacology, State University of New York Downstate Health Sciences University, Brooklyn, New York, NY, United States
- Division of Cardiology, Department of Medicine, NYU Grossman School of Medicine, New York, NY, United States
- *Correspondence: Mohamed Boutjdir,
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9
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Fan W, Sun X, Yang C, Wan J, Luo H, Liao B. Pacemaker activity and ion channels in the sinoatrial node cells: MicroRNAs and arrhythmia. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2023; 177:151-167. [PMID: 36450332 DOI: 10.1016/j.pbiomolbio.2022.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 11/13/2022] [Accepted: 11/25/2022] [Indexed: 11/29/2022]
Abstract
The primary pacemaking activity of the heart is determined by a spontaneous action potential (AP) within sinoatrial node (SAN) cells. This unique AP generation relies on two mechanisms: membrane clocks and calcium clocks. Nonhomologous arrhythmias are caused by several functional and structural changes in the myocardium. MicroRNAs (miRNAs) are essential regulators of gene expression in cardiomyocytes. These miRNAs play a vital role in regulating the stability of cardiac conduction and in the remodeling process that leads to arrhythmias. Although it remains unclear how miRNAs regulate the expression and function of ion channels in the heart, these regulatory mechanisms may support the development of emerging therapies. This study discusses the spread and generation of AP in the SAN as well as the regulation of miRNAs and individual ion channels. Arrhythmogenicity studies on ion channels will provide a research basis for miRNA modulation as a new therapeutic target.
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Affiliation(s)
- Wei Fan
- Department of Cardiovascular Surgery, Affiliated Hospital of Southwest Medical University, 25 Taiping Street, Jiangyang District, Luzhou, Sichuan Province, 646000, China
| | - Xuemei Sun
- Department of Pharmacy, Affiliated Hospital of Southwest Medical University, 25 Taiping Street, Jiangyang District, Luzhou, Sichuan Province, 646000, China
| | - Chao Yang
- Department of Cardiovascular Surgery, Affiliated Hospital of Southwest Medical University, 25 Taiping Street, Jiangyang District, Luzhou, Sichuan Province, 646000, China
| | - Juyi Wan
- Department of Cardiovascular Surgery, Affiliated Hospital of Southwest Medical University, 25 Taiping Street, Jiangyang District, Luzhou, Sichuan Province, 646000, China.
| | - Hongli Luo
- Department of Pharmacy, Affiliated Hospital of Southwest Medical University, 25 Taiping Street, Jiangyang District, Luzhou, Sichuan Province, 646000, China.
| | - Bin Liao
- Department of Cardiovascular Surgery, Affiliated Hospital of Southwest Medical University, 25 Taiping Street, Jiangyang District, Luzhou, Sichuan Province, 646000, China.
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10
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D'Souza A, Boink GJJ, Toyoda F, Mesirca P. Editorial: Cardiac Pacemaking in Health and Disease: From Genes to Function. Front Physiol 2022; 13:913506. [PMID: 35711314 PMCID: PMC9197676 DOI: 10.3389/fphys.2022.913506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 05/06/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Alicia D'Souza
- Division of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom
| | - Gerard J J Boink
- Departments of Cardiology and Medical Biology, Amsterdam University Medical Centers, Location University of Amsterdam, Amsterdam, Netherlands.,Amsterdam Cardiovascular Sciences, Research Program: Heart Failure and Arrhythmias, Amsterdam, Netherlands
| | - Futoshi Toyoda
- Department of Physiology, Shiga University of Medical Science, Otsu, Japan
| | - Pietro Mesirca
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France.,LabEx Ion Channels Science and Therapeutics, Montpellier, France
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11
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Shimizu M, Mi X, Toyoda F, Kojima A, Ding WG, Fukushima Y, Omatsu-Kanbe M, Kitagawa H, Matsuura H. Propofol, an Anesthetic Agent, Inhibits HCN Channels through the Allosteric Modulation of the cAMP-Dependent Gating Mechanism. Biomolecules 2022; 12:biom12040570. [PMID: 35454159 PMCID: PMC9032835 DOI: 10.3390/biom12040570] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 04/08/2022] [Accepted: 04/10/2022] [Indexed: 11/16/2022] Open
Abstract
Propofol is a broadly used intravenous anesthetic agent that can cause cardiovascular effects, including bradycardia and asystole. A possible mechanism for these effects is slowing cardiac pacemaker activity due to inhibition of the hyperpolarization-activated, cyclic nucleotide-gated (HCN) channels. However, it remains unclear how propofol affects the allosteric nature of the voltage- and cAMP-dependent gating mechanism in HCN channels. To address this aim, we investigated the effect of propofol on HCN channels (HCN4 and HCN2) in heterologous expression systems using a whole-cell patch clamp technique. The extracellular application of propofol substantially suppressed the maximum current at clinical concentrations. This was accompanied by a hyperpolarizing shift in the voltage dependence of channel opening. These effects were significantly attenuated by intracellular loading of cAMP, even after considering the current modification by cAMP in opposite directions. The differential degree of propofol effects in the presence and absence of cAMP was rationalized by an allosteric gating model for HCN channels, where we assumed that propofol affects allosteric couplings between the pore, voltage-sensor, and cyclic nucleotide-binding domain (CNBD). The model predicted that propofol enhanced autoinhibition of pore opening by unliganded CNBD, which was relieved by the activation of CNBD by cAMP. Taken together, these findings reveal that propofol acts as an allosteric modulator of cAMP-dependent gating in HCN channels, which may help us to better understand the clinical action of this anesthetic drug.
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Affiliation(s)
- Morihiro Shimizu
- Department of Anesthesiology, Shiga University of Medical Science, Otsu 520-2192, Japan; (M.S.); (A.K.); (Y.F.); (H.K.)
| | - Xinya Mi
- Department of Physiology, Shiga University of Medical Science, Otsu 520-2192, Japan; (X.M.); (F.T.); (M.O.-K.); (H.M.)
| | - Futoshi Toyoda
- Department of Physiology, Shiga University of Medical Science, Otsu 520-2192, Japan; (X.M.); (F.T.); (M.O.-K.); (H.M.)
| | - Akiko Kojima
- Department of Anesthesiology, Shiga University of Medical Science, Otsu 520-2192, Japan; (M.S.); (A.K.); (Y.F.); (H.K.)
| | - Wei-Guang Ding
- Department of Physiology, Shiga University of Medical Science, Otsu 520-2192, Japan; (X.M.); (F.T.); (M.O.-K.); (H.M.)
- Correspondence: ; Tel.: +81-77-548-2152; Fax: +81-77-548-2348
| | - Yutaka Fukushima
- Department of Anesthesiology, Shiga University of Medical Science, Otsu 520-2192, Japan; (M.S.); (A.K.); (Y.F.); (H.K.)
| | - Mariko Omatsu-Kanbe
- Department of Physiology, Shiga University of Medical Science, Otsu 520-2192, Japan; (X.M.); (F.T.); (M.O.-K.); (H.M.)
| | - Hirotoshi Kitagawa
- Department of Anesthesiology, Shiga University of Medical Science, Otsu 520-2192, Japan; (M.S.); (A.K.); (Y.F.); (H.K.)
| | - Hiroshi Matsuura
- Department of Physiology, Shiga University of Medical Science, Otsu 520-2192, Japan; (X.M.); (F.T.); (M.O.-K.); (H.M.)
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12
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Komosa ER, Wolfson DW, Bressan M, Cho HC, Ogle BM. Implementing Biological Pacemakers: Design Criteria for Successful. Circ Arrhythm Electrophysiol 2021; 14:e009957. [PMID: 34592837 PMCID: PMC8530973 DOI: 10.1161/circep.121.009957] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Each heartbeat that pumps blood throughout the body is initiated by an electrical impulse generated in the sinoatrial node (SAN). However, a number of disease conditions can hamper the ability of the SAN's pacemaker cells to generate consistent action potentials and maintain an orderly conduction path, leading to arrhythmias. For symptomatic patients, current treatments rely on implantation of an electronic pacing device. However, complications inherent to the indwelling hardware give pause to categorical use of device therapy for a subset of populations, including pediatric patients or those with temporary pacing needs. Cellular-based biological pacemakers, derived in vitro or in situ, could function as a therapeutic alternative to current electronic pacemakers. Understanding how biological pacemakers measure up to the SAN would facilitate defining and demonstrating its advantages over current treatments. In this review, we discuss recent approaches to creating biological pacemakers and delineate design criteria to guide future progress based on insights from basic biology of the SAN. We emphasize the need for long-term efficacy in vivo via maintenance of relevant proteins, source-sink balance, a niche reflective of the native SAN microenvironment, and chronotropic competence. With a focus on such criteria, combined with delivery methods tailored for disease indications, clinical implementation will be attainable.
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Affiliation(s)
- Elizabeth R Komosa
- Department of Biomedical Engineering (E.R.K., B.M.O.), University of Minnesota-Twin Cities, Minneapolis
- Stem Cell Institute (E.R.K., B.M.O.), University of Minnesota-Twin Cities, Minneapolis
| | - David W Wolfson
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta (D.W.W., H.C.C.)
| | - Michael Bressan
- Department of Cell Biology and Physiology (M.B.), University of North Carolina-Chapel Hill
- McAllister Heart Institute (M.B.), University of North Carolina-Chapel Hill
| | - Hee Cheol Cho
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta (D.W.W., H.C.C.)
- Department of Pediatrics, Emory University, Atlanta, GA (H.C.C.)
| | - Brenda M Ogle
- Department of Biomedical Engineering (E.R.K., B.M.O.), University of Minnesota-Twin Cities, Minneapolis
- Stem Cell Institute (E.R.K., B.M.O.), University of Minnesota-Twin Cities, Minneapolis
- Department of Pediatrics (B.M.O), University of Minnesota-Twin Cities, Minneapolis
- Lillehei Heart Institute (B.M.O), University of Minnesota-Twin Cities, Minneapolis
- Institute for Engineering in Medicine (B.M.O), University of Minnesota-Twin Cities, Minneapolis
- Masonic Cancer Center (B.M.O), University of Minnesota-Twin Cities, Minneapolis
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13
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Anderson A, Vo BN, de Velasco EMF, Hopkins CR, Weaver CD, Wickman K. Characterization of VU0468554, a New Selective Inhibitor of Cardiac G Protein-Gated Inwardly Rectifying K + Channels. Mol Pharmacol 2021; 100:540-547. [PMID: 34503975 DOI: 10.1124/molpharm.121.000311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 09/01/2021] [Indexed: 11/22/2022] Open
Abstract
G protein-gated inwardly rectifying K+ (GIRK) channels are critical mediators of excitability in the heart and brain. Enhanced GIRK-channel activity has been implicated in the pathogenesis of supraventricular arrhythmias, including atrial fibrillation. The lack of selective pharmacological tools has impeded efforts to investigate the therapeutic potential of cardiac GIRK-channel interventions in arrhythmias. Here, we characterize a recently identified GIRK-channel inhibitor, VU0468554. Using whole-cell electrophysiological approaches and primary cultures of sinoatrial nodal cells and hippocampal neurons, we show that VU0468554 more effectively inhibits the cardiac GIRK channel than the neuronal GIRK channel. Concentration-response experiments suggest that VU0468554 inhibits Gβγ-activated GIRK channels in noncompetitive and potentially uncompetitive fashion. In contrast, VU0468554 competitively inhibits GIRK-channel activation by ML297, a GIRK-channel activator containing the same chemical scaffold as VU0468554. In the isolated heart model, VU0468554 partially reversed carbachol-induced bradycardia in hearts from wild-type mice but not Girk4-/- mice. Collectively, these data suggest that VU0468554 represents a promising new pharmacological tool for targeting cardiac GIRK channels with therapeutic implications for relevant cardiac arrhythmias. SIGNIFICANCE STATEMENT: Although cardiac GIRK-channel inhibition shows promise for the treatment of supraventricular arrhythmias, the absence of subtype-selective channel inhibitors has hindered exploration into this therapeutic strategy. This study utilizes whole-cell patch-clamp electrophysiology to characterize the new GIRK-channel inhibitor VU0468554 in human embryonic kidney 293T cells and primary cultures. We report that VU0468554 exhibits a favorable pharmacodynamic profile for cardiac over neuronal GIRK channels and partially reverses GIRK-mediated bradycardia in the isolated mouse heart model.
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Affiliation(s)
- Allison Anderson
- Graduate Program in Pharmacology (A.A., B.N.V.) and Department of Pharmacology (E.M.F.d.V., K.W.), University of Minnesota, Minneapolis, Minnesota; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska (C.R.H.); and Departments of Pharmacology and Chemistry and Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (C.D.W.)
| | - Baovi N Vo
- Graduate Program in Pharmacology (A.A., B.N.V.) and Department of Pharmacology (E.M.F.d.V., K.W.), University of Minnesota, Minneapolis, Minnesota; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska (C.R.H.); and Departments of Pharmacology and Chemistry and Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (C.D.W.)
| | - Ezequiel Marron Fernandez de Velasco
- Graduate Program in Pharmacology (A.A., B.N.V.) and Department of Pharmacology (E.M.F.d.V., K.W.), University of Minnesota, Minneapolis, Minnesota; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska (C.R.H.); and Departments of Pharmacology and Chemistry and Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (C.D.W.)
| | - Corey R Hopkins
- Graduate Program in Pharmacology (A.A., B.N.V.) and Department of Pharmacology (E.M.F.d.V., K.W.), University of Minnesota, Minneapolis, Minnesota; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska (C.R.H.); and Departments of Pharmacology and Chemistry and Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (C.D.W.)
| | - C David Weaver
- Graduate Program in Pharmacology (A.A., B.N.V.) and Department of Pharmacology (E.M.F.d.V., K.W.), University of Minnesota, Minneapolis, Minnesota; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska (C.R.H.); and Departments of Pharmacology and Chemistry and Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (C.D.W.)
| | - Kevin Wickman
- Graduate Program in Pharmacology (A.A., B.N.V.) and Department of Pharmacology (E.M.F.d.V., K.W.), University of Minnesota, Minneapolis, Minnesota; Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska (C.R.H.); and Departments of Pharmacology and Chemistry and Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (C.D.W.)
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14
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Regulation of sinus node pacemaking and atrioventricular node conduction by HCN channels in health and disease. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2021; 166:61-85. [PMID: 34197836 DOI: 10.1016/j.pbiomolbio.2021.06.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 06/02/2021] [Accepted: 06/14/2021] [Indexed: 12/19/2022]
Abstract
The funny current, If, was first recorded in the heart 40 or more years ago by Dario DiFrancesco and others. Since then, we have learnt that If plays an important role in pacemaking in the sinus node, the innate pacemaker of the heart, and more recently evidence has accumulated to show that If may play an important role in action potential conduction through the atrioventricular (AV) node. Evidence has also accumulated to show that regulation of the transcription and translation of the underlying Hcn genes plays an important role in the regulation of sinus node pacemaking and AV node conduction under normal physiological conditions - in athletes, during the circadian rhythm, in pregnancy, and during postnatal development - as well as pathological states - ageing, heart failure, pulmonary hypertension, diabetes and atrial fibrillation. There may be yet more pathological conditions involving changes in the expression of the Hcn genes. Here, we review the role of If and the underlying HCN channels in physiological and pathological changes of the sinus and AV nodes and we begin to explore the signalling pathways (microRNAs, transcription factors, GIRK4, the autonomic nervous system and inflammation) involved in this regulation. This review is dedicated to Dario DiFrancesco on his retirement.
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15
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DiFrancesco ML, Mesirca P, Bidaud I, Isbrandt D, Mangoni ME. The funny current in genetically modified mice. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2021; 166:39-50. [PMID: 34129872 DOI: 10.1016/j.pbiomolbio.2021.06.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 05/18/2021] [Accepted: 06/07/2021] [Indexed: 12/27/2022]
Abstract
Since its first description in 1979, the hyperpolarization-activated funny current (If) has been the object of intensive research aimed at understanding its role in cardiac pacemaker activity and its modulation by the sympathetic and parasympathetic branches of the autonomic nervous system. If was described in isolated tissue strips of the rabbit sinoatrial node using the double-electrode voltage-clamp technique. Since then, the rabbit has been the principal animal model for studying pacemaker activity and If for more than 20 years. In 2001, the first study describing the electrophysiological properties of mouse sinoatrial pacemaker myocytes and those of If was published. It was soon followed by the description of murine myocytes of the atrioventricular node and the Purkinje fibres. The sinoatrial node of genetically modified mice has become a very popular model for studying the mechanisms of cardiac pacemaker activity. This field of research benefits from the impressive advancement of in-vivo exploration techniques of physiological parameters, imaging, genetics, and large-scale genomic approaches. The present review discusses the influence of mouse genetic on the most recent knowledge of the funny current's role in the physiology and pathophysiology of cardiac pacemaker activity. Genetically modified mice have provided important insights into the role of If in determining intrinsic automaticity in vivo and in myocytes of the conduction system. In addition, gene targeting of f-(HCN) channel isoforms have contributed to elucidating the current's role in the regulation of heart rate by the parasympathetic nervous system. This review is dedicated to Dario DiFrancesco on his retirement.
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Affiliation(s)
- Mattia L DiFrancesco
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genoa, Italy; IRCCS Ospedale Policlinico San Martino, Genoa, Italy; Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France; LabEx Ion Channels Science and Therapeutics (ICST), France.
| | - Pietro Mesirca
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France; LabEx Ion Channels Science and Therapeutics (ICST), France
| | - Isabelle Bidaud
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France; LabEx Ion Channels Science and Therapeutics (ICST), France
| | - Dirk Isbrandt
- Deutsches Zentrum für Neurodegenerative Erktankungen (DZNE), Bonn, Germany; University of Cologne, Institute for Molecular and Behavioral Neuroscience, Cologne, Germany
| | - Matteo E Mangoni
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France; LabEx Ion Channels Science and Therapeutics (ICST), France.
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16
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Wallace MJ, El Refaey M, Mesirca P, Hund TJ, Mangoni ME, Mohler PJ. Genetic Complexity of Sinoatrial Node Dysfunction. Front Genet 2021; 12:654925. [PMID: 33868385 PMCID: PMC8047474 DOI: 10.3389/fgene.2021.654925] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 03/01/2021] [Indexed: 12/13/2022] Open
Abstract
The pacemaker cells of the cardiac sinoatrial node (SAN) are essential for normal cardiac automaticity. Dysfunction in cardiac pacemaking results in human sinoatrial node dysfunction (SND). SND more generally occurs in the elderly population and is associated with impaired pacemaker function causing abnormal heart rhythm. Individuals with SND have a variety of symptoms including sinus bradycardia, sinus arrest, SAN block, bradycardia/tachycardia syndrome, and syncope. Importantly, individuals with SND report chronotropic incompetence in response to stress and/or exercise. SND may be genetic or secondary to systemic or cardiovascular conditions. Current management of patients with SND is limited to the relief of arrhythmia symptoms and pacemaker implantation if indicated. Lack of effective therapeutic measures that target the underlying causes of SND renders management of these patients challenging due to its progressive nature and has highlighted a critical need to improve our understanding of its underlying mechanistic basis of SND. This review focuses on current information on the genetics underlying SND, followed by future implications of this knowledge in the management of individuals with SND.
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Affiliation(s)
- Michael J. Wallace
- Frick Center for Heart Failure and Arrhythmia Research, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Mona El Refaey
- Frick Center for Heart Failure and Arrhythmia Research, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Pietro Mesirca
- CNRS, INSERM, Institut de Génomique Fonctionnelle, Université de Montpellier, Montpellier, France
- Laboratory of Excellence ICST, Montpellier, France
| | - Thomas J. Hund
- Frick Center for Heart Failure and Arrhythmia Research, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, OH, United States
| | - Matteo E. Mangoni
- CNRS, INSERM, Institut de Génomique Fonctionnelle, Université de Montpellier, Montpellier, France
- Laboratory of Excellence ICST, Montpellier, France
| | - Peter J. Mohler
- Frick Center for Heart Failure and Arrhythmia Research, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Division of Cardiovascular Medicine, Department of Internal Medicine, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States
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Saljic A, Jespersen T, Buhl R. Anti-arrhythmic investigations in large animal models of atrial fibrillation. Br J Pharmacol 2021; 179:838-858. [PMID: 33624840 DOI: 10.1111/bph.15417] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 02/10/2021] [Accepted: 02/11/2021] [Indexed: 12/13/2022] Open
Abstract
Atrial fibrillation (AF) constitutes an increasing health problem in the aging population. Animal models reflecting human phenotypes are needed to understand the mechanisms of AF, as well as to test new pharmacological interventions. In recent years, a number of large animal models, primarily pigs, goats, dog and horses have been used in AF research. These animals can to a certain extent recapitulate the human pathophysiological characteristics and serve as valuable tools in investigating new pharmacological interventions for treating AF. This review focuses on anti-arrhythmic investigations in large animals. Initially, spontaneous AF in small and large mammals is discussed. This is followed by a short presentation of frequently used methods for inducing short- and long-term AF. The major focus of the review is on anti-arrhythmic compounds either frequently used in the human clinic (ranolazine, flecainide, vernakalant and amiodarone) or being promising new AF medicine candidates (IK,Ach , ISK,Ca and IK2P blockers).
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Affiliation(s)
- Arnela Saljic
- Laboratory of Cardiac Physiology, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Jespersen
- Laboratory of Cardiac Physiology, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Rikke Buhl
- Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Taastrup, Denmark
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18
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RNAseq shows an all-pervasive day-night rhythm in the transcriptome of the pacemaker of the heart. Sci Rep 2021; 11:3565. [PMID: 33574422 PMCID: PMC7878777 DOI: 10.1038/s41598-021-82202-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 01/01/2021] [Indexed: 12/12/2022] Open
Abstract
Physiological systems vary in a day-night manner anticipating increased demand at a particular time. Heart is no exception. Cardiac output is primarily determined by heart rate and unsurprisingly this varies in a day-night manner and is higher during the day in the human (anticipating increased day-time demand). Although this is attributed to a day-night rhythm in post-translational ion channel regulation in the heart's pacemaker, the sinus node, by the autonomic nervous system, we investigated whether there is a day-night rhythm in transcription. RNAseq revealed that ~ 44% of the sinus node transcriptome (7134 of 16,387 transcripts) has a significant day-night rhythm. The data revealed the oscillating components of an intrinsic circadian clock. Presumably this clock (or perhaps the master circadian clock in the suprachiasmatic nucleus) is responsible for the rhythm observed in the transcriptional machinery, which in turn is responsible for the rhythm observed in the transcriptome. For example, there is a rhythm in transcripts responsible for the two principal pacemaker mechanisms (membrane and Ca2+ clocks), transcripts responsible for receptors and signalling pathways known to control pacemaking, transcripts from genes identified by GWAS as determinants of resting heart rate, and transcripts from genes responsible for familial and acquired sick sinus syndrome.
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19
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Bidaud I, D'Souza A, Forte G, Torre E, Greuet D, Thirard S, Anderson C, Chung You Chong A, Torrente AG, Roussel J, Wickman K, Boyett MR, Mangoni ME, Mesirca P. Genetic Ablation of G Protein-Gated Inwardly Rectifying K + Channels Prevents Training-Induced Sinus Bradycardia. Front Physiol 2021; 11:519382. [PMID: 33551824 PMCID: PMC7857143 DOI: 10.3389/fphys.2020.519382] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 12/17/2020] [Indexed: 11/13/2022] Open
Abstract
Background: Endurance athletes are prone to bradyarrhythmias, which in the long-term may underscore the increased incidence of pacemaker implantation reported in this population. Our previous work in rodent models has shown training-induced sinus bradycardia to be due to microRNA (miR)-mediated transcriptional remodeling of the HCN4 channel, leading to a reduction of the "funny" (I f) current in the sinoatrial node (SAN). Objective: To test if genetic ablation of G-protein-gated inwardly rectifying potassium channel, also known as I KACh channels prevents sinus bradycardia induced by intensive exercise training in mice. Methods: Control wild-type (WT) and mice lacking GIRK4 (Girk4 -/-), an integral subunit of I KACh were assigned to trained or sedentary groups. Mice in the trained group underwent 1-h exercise swimming twice a day for 28 days, 7 days per week. We performed electrocardiogram recordings and echocardiography in both groups at baseline, during and after the training period. At training cessation, mice were euthanized and SAN tissues were isolated for patch clamp recordings in isolated SAN cells and molecular profiling by quantitative PCR (qPCR) and western blotting. Results: At swimming cessation trained WT mice presented with a significantly lower resting HR that was reversible by acute I KACh block whereas Girk4 -/- mice failed to develop a training-induced sinus bradycardia. In line with HR reduction, action potential rate, density of I f, as well as of T- and L-type Ca2+ currents (I CaT and I CaL ) were significantly reduced only in SAN cells obtained from WT-trained mice. I f reduction in WT mice was concomitant with downregulation of HCN4 transcript and protein, attributable to increased expression of corresponding repressor microRNAs (miRs) whereas reduced I CaL in WT mice was associated with reduced Cav1.3 protein levels. Strikingly, I KACh ablation suppressed all training-induced molecular remodeling observed in WT mice. Conclusion: Genetic ablation of cardiac I KACh in mice prevents exercise-induced sinus bradycardia by suppressing training induced remodeling of inward currents I f, I CaT and I CaL due in part to the prevention of miR-mediated transcriptional remodeling of HCN4 and likely post transcriptional remodeling of Cav1.3. Strategies targeting cardiac I KACh may therefore represent an alternative to pacemaker implantation for bradyarrhythmias seen in some veteran athletes.
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Affiliation(s)
- Isabelle Bidaud
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France.,LabEx Ion Channels Science and Therapeutics, Montpellier, France
| | - Alicia D'Souza
- Division of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom
| | - Gabriella Forte
- Division of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom
| | - Eleonora Torre
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France.,LabEx Ion Channels Science and Therapeutics, Montpellier, France
| | - Denis Greuet
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Steeve Thirard
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Cali Anderson
- Division of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom
| | - Antony Chung You Chong
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France.,LabEx Ion Channels Science and Therapeutics, Montpellier, France
| | - Angelo G Torrente
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France.,LabEx Ion Channels Science and Therapeutics, Montpellier, France
| | - Julien Roussel
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Kevin Wickman
- Department of Pharmacology, University of Minnesota, Minneapolis, MN, United States
| | - Mark R Boyett
- Division of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Matteo E Mangoni
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France.,LabEx Ion Channels Science and Therapeutics, Montpellier, France
| | - Pietro Mesirca
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France.,LabEx Ion Channels Science and Therapeutics, Montpellier, France
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20
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Mesirca P, Fedorov VV, Hund TJ, Torrente AG, Bidaud I, Mohler PJ, Mangoni ME. Pharmacologic Approach to Sinoatrial Node Dysfunction. Annu Rev Pharmacol Toxicol 2021; 61:757-778. [PMID: 33017571 PMCID: PMC7790915 DOI: 10.1146/annurev-pharmtox-031120-115815] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The spontaneous activity of the sinoatrial node initiates the heartbeat. Sino-atrial node dysfunction (SND) and sick sinoatrial (sick sinus) syndrome are caused by the heart's inability to generate a normal sinoatrial node action potential. In clinical practice, SND is generally considered an age-related pathology, secondary to degenerative fibrosis of the heart pacemaker tissue. However, other forms of SND exist, including idiopathic primary SND, which is genetic, and forms that are secondary to cardiovascular or systemic disease. The incidence of SND in the general population is expected to increase over the next half century, boosting the need to implant electronic pacemakers. During the last two decades, our knowledge of sino-atrial node physiology and of the pathophysiological mechanisms underlying SND has advanced considerably. This review summarizes the current knowledge about SND mechanisms and discusses the possibility of introducing new pharmacologic therapies for treating SND.
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Affiliation(s)
- Pietro Mesirca
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34096 Montpellier, France;
- LabEx Ion Channels Science and Therapeutics (ICST), 06560 Nice, France
| | - Vadim V Fedorov
- Frick Center for Heart Failure and Arrhythmia at the Davis Heart and Lung Research Institute, The Ohio State University, Columbus, Ohio 43210, USA
- Department of Physiology and Cell Biology, The Ohio State University College of Medicine, Wexner Medical Center, Columbus, Ohio 43210, USA
| | - Thomas J Hund
- Frick Center for Heart Failure and Arrhythmia at the Davis Heart and Lung Research Institute, The Ohio State University, Columbus, Ohio 43210, USA
- Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio 43210, USA
| | - Angelo G Torrente
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34096 Montpellier, France;
- LabEx Ion Channels Science and Therapeutics (ICST), 06560 Nice, France
| | - Isabelle Bidaud
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34096 Montpellier, France;
- LabEx Ion Channels Science and Therapeutics (ICST), 06560 Nice, France
| | - Peter J Mohler
- Frick Center for Heart Failure and Arrhythmia at the Davis Heart and Lung Research Institute, The Ohio State University, Columbus, Ohio 43210, USA
- Department of Physiology and Cell Biology, The Ohio State University College of Medicine, Wexner Medical Center, Columbus, Ohio 43210, USA
- Department of Internal Medicine, The Ohio State University College of Medicine, Columbus, Ohio 43210, USA
| | - Matteo E Mangoni
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34096 Montpellier, France;
- LabEx Ion Channels Science and Therapeutics (ICST), 06560 Nice, France
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21
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Baudot M, Torre E, Bidaud I, Louradour J, Torrente AG, Fossier L, Talssi L, Nargeot J, Barrère-Lemaire S, Mesirca P, Mangoni ME. Concomitant genetic ablation of L-type Ca v1.3 (α 1D) and T-type Ca v3.1 (α 1G) Ca 2+ channels disrupts heart automaticity. Sci Rep 2020; 10:18906. [PMID: 33144668 PMCID: PMC7642305 DOI: 10.1038/s41598-020-76049-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 10/15/2020] [Indexed: 12/02/2022] Open
Abstract
Cardiac automaticity is set by pacemaker activity of the sinus node (SAN). In addition to the ubiquitously expressed cardiac voltage-gated L-type Cav1.2 Ca2+ channel isoform, pacemaker cells within the SAN and the atrioventricular node co-express voltage-gated L-type Cav1.3 and T-type Cav3.1 Ca2+ channels (SAN-VGCCs). The role of SAN-VGCCs in automaticity is incompletely understood. We used knockout mice carrying individual genetic ablation of Cav1.3 (Cav1.3−/−) or Cav3.1 (Cav3.1−/−) channels and double mutant Cav1.3−/−/Cav3.1−/− mice expressing only Cav1.2 channels. We show that concomitant loss of SAN-VGCCs prevents physiological SAN automaticity, blocks impulse conduction and compromises ventricular rhythmicity. Coexpression of SAN-VGCCs is necessary for impulse formation in the central SAN. In mice lacking SAN-VGCCs, residual pacemaker activity is predominantly generated in peripheral nodal and extranodal sites by f-channels and TTX-sensitive Na+ channels. In beating SAN cells, ablation of SAN-VGCCs disrupted late diastolic local intracellular Ca2+ release, which demonstrates an important role for these channels in supporting the sarcoplasmic reticulum based “Ca2+clock” mechanism during normal pacemaking. These data implicate an underappreciated role for co-expression of SAN-VGCCs in heart automaticity and define an integral role for these channels in mechanisms that control the heartbeat.
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Affiliation(s)
- Matthias Baudot
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, Inserm, 141, rue de la cardonille, 34094, Montpellier, France.,LabEx ICST, Montpellier, France
| | - Eleonora Torre
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, Inserm, 141, rue de la cardonille, 34094, Montpellier, France.,LabEx ICST, Montpellier, France.,Department of Biotechnology and Biosciences, Università Degli Studi di Milano-Bicocca, Milan, Italy
| | - Isabelle Bidaud
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, Inserm, 141, rue de la cardonille, 34094, Montpellier, France.,LabEx ICST, Montpellier, France
| | - Julien Louradour
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, Inserm, 141, rue de la cardonille, 34094, Montpellier, France.,LabEx ICST, Montpellier, France
| | - Angelo G Torrente
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, Inserm, 141, rue de la cardonille, 34094, Montpellier, France.,LabEx ICST, Montpellier, France
| | - Lucile Fossier
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, Inserm, 141, rue de la cardonille, 34094, Montpellier, France.,LabEx ICST, Montpellier, France
| | - Leïla Talssi
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, Inserm, 141, rue de la cardonille, 34094, Montpellier, France.,LabEx ICST, Montpellier, France
| | - Joël Nargeot
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, Inserm, 141, rue de la cardonille, 34094, Montpellier, France.,LabEx ICST, Montpellier, France
| | - Stéphanie Barrère-Lemaire
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, Inserm, 141, rue de la cardonille, 34094, Montpellier, France.,LabEx ICST, Montpellier, France
| | - Pietro Mesirca
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, Inserm, 141, rue de la cardonille, 34094, Montpellier, France. .,LabEx ICST, Montpellier, France.
| | - Matteo E Mangoni
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, Inserm, 141, rue de la cardonille, 34094, Montpellier, France. .,LabEx ICST, Montpellier, France.
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22
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Maurocalcin and its analog MCaE12A facilitate Ca2+ mobilization in cardiomyocytes. Biochem J 2020; 477:3985-3999. [PMID: 33034621 DOI: 10.1042/bcj20200206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 09/23/2020] [Accepted: 10/09/2020] [Indexed: 11/17/2022]
Abstract
Ryanodine receptors are responsible for the massive release of calcium from the sarcoplasmic reticulum that triggers heart muscle contraction. Maurocalcin (MCa) is a 33 amino acid peptide toxin known to target skeletal ryanodine receptor. We investigated the effect of MCa and its analog MCaE12A on isolated cardiac ryanodine receptor (RyR2), and showed that they increase RyR2 sensitivity to cytoplasmic calcium concentrations promoting channel opening and decreases its sensitivity to inhibiting calcium concentrations. By measuring intracellular Ca2+ transients, calcium sparks and contraction on cardiomyocytes isolated from adult rats or differentiated from human-induced pluripotent stem cells, we demonstrated that MCaE12A passively penetrates cardiomyocytes and promotes the abnormal opening of RyR2. We also investigated the effect of MCaE12A on the pacemaker activity of sinus node cells from different mice lines and showed that, MCaE12A improves pacemaker activity of sinus node cells obtained from mice lacking L-type Cav1.3 channel, or following selective pharmacologic inhibition of calcium influx via Cav1.3. Our results identify MCaE12A as a high-affinity modulator of RyR2 and make it an important tool for RyR2 structure-to-function studies as well as for manipulating Ca2+ homeostasis and dynamic of cardiac cells.
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23
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Torrente AG, Mesirca P, Bidaud I, Mangoni ME. Channelopathies of voltage-gated L-type Cav1.3/α 1D and T-type Cav3.1/α 1G Ca 2+ channels in dysfunction of heart automaticity. Pflugers Arch 2020; 472:817-830. [PMID: 32601767 DOI: 10.1007/s00424-020-02421-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 06/12/2020] [Accepted: 06/19/2020] [Indexed: 10/24/2022]
Abstract
The heart automaticity is a fundamental physiological function in vertebrates. The cardiac impulse is generated in the sinus node by a specialized population of spontaneously active myocytes known as "pacemaker cells." Failure in generating or conducting spontaneous activity induces dysfunction in cardiac automaticity. Several families of ion channels are involved in the generation and regulation of the heart automaticity. Among those, voltage-gated L-type Cav1.3 (α1D) and T-type Cav3.1 (α1G) Ca2+ channels play important roles in the spontaneous activity of pacemaker cells. Ca2+ channel channelopathies specifically affecting cardiac automaticity are considered rare. Recent research on familial disease has identified mutations in the Cav1.3-encoding CACNA1D gene that underlie congenital sinus node dysfunction and deafness (OMIM # 614896). In addition, both Cav1.3 and Cav3.1 channels have been identified as pathophysiological targets of sinus node dysfunction and heart block, caused by congenital autoimmune disease of the cardiac conduction system. The discovery of channelopathies linked to Cav1.3 and Cav3.1 channels underscores the importance of Ca2+ channels in the generation and regulation of heart's automaticity.
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Affiliation(s)
- Angelo G Torrente
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 141, rue de la cardonille, 34094, Montpellier, France.,LabEx Ion Channels Science and Therapeutics (ICST), Montpellier, France
| | - Pietro Mesirca
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 141, rue de la cardonille, 34094, Montpellier, France.,LabEx Ion Channels Science and Therapeutics (ICST), Montpellier, France
| | - Isabelle Bidaud
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 141, rue de la cardonille, 34094, Montpellier, France.,LabEx Ion Channels Science and Therapeutics (ICST), Montpellier, France
| | - Matteo E Mangoni
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 141, rue de la cardonille, 34094, Montpellier, France. .,LabEx Ion Channels Science and Therapeutics (ICST), Montpellier, France.
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24
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Inhibition of G protein-gated K + channels by tertiapin-Q rescues sinus node dysfunction and atrioventricular conduction in mouse models of primary bradycardia. Sci Rep 2020; 10:9835. [PMID: 32555258 PMCID: PMC7300035 DOI: 10.1038/s41598-020-66673-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 05/21/2020] [Indexed: 02/06/2023] Open
Abstract
Sinus node (SAN) dysfunction (SND) manifests as low heart rate (HR) and is often accompanied by atrial tachycardia or atrioventricular (AV) block. The only currently available therapy for chronic SND is the implantation of an electronic pacemaker. Because of the growing burden of SND in the population, new pharmacological therapies of chronic SND and heart block are desirable. We developed a collection of genetically modified mouse strains recapitulating human primary SND associated with different degrees of AV block. These mice were generated with genetic ablation of L-type Cav1.3 (Cav1.3-/-), T-type Cav3.1 (Cav3.1-/-), or both (Cav1.3-/-/Cav3.1-/-). We also studied mice haplo-insufficient for the Na+ channel Nav1.5 (Nav1.5+/) and mice in which the cAMP-dependent regulation of hyperpolarization-activated f-(HCN4) channels has been abolished (HCN4-CNBD). We analysed, by telemetric ECG recording, whether pharmacological inhibition of the G-protein-activated K+ current (IKACh) by the peptide tertiapin-Q could improve HR and AV conduction in these mouse strains. Tertiapin-Q significantly improved the HR of Cav1.3-/- (19%), Cav1.3-/-/Cav3.1-/- (23%) and HCN4-CNBD (14%) mice. Tertiapin-Q also improved cardiac conduction of Nav1.5+/- mice by 24%. Our data suggest that the development of pharmacological IKACh inhibitors for the management of SND and conduction disease is a viable approach.
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25
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Yamada N, Asano Y, Fujita M, Yamazaki S, Inanobe A, Matsuura N, Kobayashi H, Ohno S, Ebana Y, Tsukamoto O, Ishino S, Takuwa A, Kioka H, Yamashita T, Hashimoto N, Zankov DP, Shimizu A, Asakura M, Asanuma H, Kato H, Nishida Y, Miyashita Y, Shinomiya H, Naiki N, Hayashi K, Makiyama T, Ogita H, Miura K, Ueshima H, Komuro I, Yamagishi M, Horie M, Kawakami K, Furukawa T, Koizumi A, Kurachi Y, Sakata Y, Minamino T, Kitakaze M, Takashima S. Mutant KCNJ3 and KCNJ5 Potassium Channels as Novel Molecular Targets in Bradyarrhythmias and Atrial Fibrillation. Circulation 2020; 139:2157-2169. [PMID: 30764634 DOI: 10.1161/circulationaha.118.036761] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Bradyarrhythmia is a common clinical manifestation. Although the majority of cases are acquired, genetic analysis of families with bradyarrhythmia has identified a growing number of causative gene mutations. Because the only ultimate treatment for symptomatic bradyarrhythmia has been invasive surgical implantation of a pacemaker, the discovery of novel therapeutic molecular targets is necessary to improve prognosis and quality of life. METHODS We investigated a family containing 7 individuals with autosomal dominant bradyarrhythmias of sinus node dysfunction, atrial fibrillation with slow ventricular response, and atrioventricular block. To identify the causative mutation, we conducted the family-based whole exome sequencing and genome-wide linkage analysis. We characterized the mutation-related mechanisms based on the pathophysiology in vitro. After generating a transgenic animal model to confirm the human phenotypes of bradyarrhythmia, we also evaluated the efficacy of a newly identified molecular-targeted compound to upregulate heart rate in bradyarrhythmias by using the animal model. RESULTS We identified one heterozygous mutation, KCNJ3 c.247A>C, p.N83H, as a novel cause of hereditary bradyarrhythmias in this family. KCNJ3 encodes the inwardly rectifying potassium channel Kir3.1, which combines with Kir3.4 (encoded by KCNJ5) to form the acetylcholine-activated potassium channel ( IKACh channel) with specific expression in the atrium. An additional study using a genome cohort of 2185 patients with sporadic atrial fibrillation revealed another 5 rare mutations in KCNJ3 and KCNJ5, suggesting the relevance of both genes to these arrhythmias. Cellular electrophysiological studies revealed that the KCNJ3 p.N83H mutation caused a gain of IKACh channel function by increasing the basal current, even in the absence of m2 muscarinic receptor stimulation. We generated transgenic zebrafish expressing mutant human KCNJ3 in the atrium specifically. It is interesting to note that the selective IKACh channel blocker NIP-151 repressed the increased current and improved bradyarrhythmia phenotypes in the mutant zebrafish. CONCLUSIONS The IKACh channel is associated with the pathophysiology of bradyarrhythmia and atrial fibrillation, and the mutant IKACh channel ( KCNJ3 p.N83H) can be effectively inhibited by NIP-151, a selective IKACh channel blocker. Thus, the IKACh channel might be considered to be a suitable pharmacological target for patients who have bradyarrhythmia with a gain-of-function mutation in the IKACh channel.
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Affiliation(s)
- Noriaki Yamada
- Departments of Cardiovascular Medicine (N.Y., Y.A., A.T., H. Kioka, Y.M., H.S., Y.S.), Osaka University Graduate School of Medicine, Suita, Japan
| | - Yoshihiro Asano
- Departments of Cardiovascular Medicine (N.Y., Y.A., A.T., H. Kioka, Y.M., H.S., Y.S.), Osaka University Graduate School of Medicine, Suita, Japan
| | - Masashi Fujita
- Department of Onco-cardiology, Osaka International Cancer Institute, Japan (M.F.)
| | - Satoru Yamazaki
- Departments of Cell Biology (S.Y.), National Cerebral and Cardiovascular Center, Suita, Japan
| | - Atsushi Inanobe
- Pharmacology (A.I., Y.K.), Osaka University Graduate School of Medicine, Suita, Japan
| | - Norio Matsuura
- Departments of Health and Environmental Sciences (N.M.), Kyoto University Graduate School of Medicine, Japan
| | - Hatasu Kobayashi
- Department of Biomedical Sciences, College of Life and Health Sciences Chubu University, Kasugai, Japan (H. Kobayashi)
| | - Seiko Ohno
- Bioscience and Genetics (S.O.), National Cerebral and Cardiovascular Center, Suita, Japan.,Center for Epidemiologic Research in Asia (S.O., K.M., H.U., M.H.), Shiga University of Medical Science, Otsu, Japan
| | - Yusuke Ebana
- Life Science and Bioethics Research Center (Y.E.), Tokyo Medical and Dental University, Japan
| | - Osamu Tsukamoto
- Medical Biochemistry (O.T., H. Kato, Y.N., S.T.), Osaka University Graduate School of Medicine, Suita, Japan
| | - Saki Ishino
- Center of Medical Innovation and Translational Research (S.I.), Osaka University Graduate School of Medicine, Suita, Japan
| | - Ayako Takuwa
- Departments of Cardiovascular Medicine (N.Y., Y.A., A.T., H. Kioka, Y.M., H.S., Y.S.), Osaka University Graduate School of Medicine, Suita, Japan
| | - Hidetaka Kioka
- Departments of Cardiovascular Medicine (N.Y., Y.A., A.T., H. Kioka, Y.M., H.S., Y.S.), Osaka University Graduate School of Medicine, Suita, Japan
| | - Toru Yamashita
- Pharmaceuticals Division, Nissan Chemical Corporation, Tokyo, Japan (T.Y., N.H.)
| | - Norio Hashimoto
- Pharmaceuticals Division, Nissan Chemical Corporation, Tokyo, Japan (T.Y., N.H.)
| | - Dimitar P Zankov
- Division of Molecular Medical Biochemistry, Department of Biochemistry and Molecular Biology (D.P.Z., A.S., H.O.), Shiga University of Medical Science, Otsu, Japan
| | - Akio Shimizu
- Division of Molecular Medical Biochemistry, Department of Biochemistry and Molecular Biology (D.P.Z., A.S., H.O.), Shiga University of Medical Science, Otsu, Japan
| | - Masanori Asakura
- Cardiovascular Division, Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya, Japan (M.A.)
| | - Hiroshi Asanuma
- Department of Internal Medicine, Meiji University of Integrative Medicine, Nantan, Japan (H.A.)
| | - Hisakazu Kato
- Medical Biochemistry (O.T., H. Kato, Y.N., S.T.), Osaka University Graduate School of Medicine, Suita, Japan
| | - Yuya Nishida
- Medical Biochemistry (O.T., H. Kato, Y.N., S.T.), Osaka University Graduate School of Medicine, Suita, Japan
| | - Yohei Miyashita
- Departments of Cardiovascular Medicine (N.Y., Y.A., A.T., H. Kioka, Y.M., H.S., Y.S.), Osaka University Graduate School of Medicine, Suita, Japan
| | - Haruki Shinomiya
- Departments of Cardiovascular Medicine (N.Y., Y.A., A.T., H. Kioka, Y.M., H.S., Y.S.), Osaka University Graduate School of Medicine, Suita, Japan
| | - Nobu Naiki
- Departments of Cardiovascular Medicine (N.N., M.H.), Shiga University of Medical Science, Otsu, Japan
| | - Kenshi Hayashi
- Department of Cardiovascular and Internal Medicine, Kanazawa University Graduate School of Medicine, Kanazawa, Japan (K.H., M.Y.)
| | - Takeru Makiyama
- Cardiovascular Medicine (T. Makiyama), Kyoto University Graduate School of Medicine, Japan
| | - Hisakazu Ogita
- Division of Molecular Medical Biochemistry, Department of Biochemistry and Molecular Biology (D.P.Z., A.S., H.O.), Shiga University of Medical Science, Otsu, Japan
| | - Katsuyuki Miura
- Center for Epidemiologic Research in Asia (S.O., K.M., H.U., M.H.), Shiga University of Medical Science, Otsu, Japan.,Public Health (K.M., H.U.), Shiga University of Medical Science, Otsu, Japan
| | - Hirotsugu Ueshima
- Center for Epidemiologic Research in Asia (S.O., K.M., H.U., M.H.), Shiga University of Medical Science, Otsu, Japan.,Public Health (K.M., H.U.), Shiga University of Medical Science, Otsu, Japan
| | - Issei Komuro
- Department of Cardiovascular Medicine, The University of Tokyo Graduate School of Medicine, Japan (I.K.)
| | - Masakazu Yamagishi
- Department of Cardiovascular and Internal Medicine, Kanazawa University Graduate School of Medicine, Kanazawa, Japan (K.H., M.Y.).,Department of Human Sciences, Osaka University of Human Sciences, Settsu, Japan (M.Y.)
| | - Minoru Horie
- Center for Epidemiologic Research in Asia (S.O., K.M., H.U., M.H.), Shiga University of Medical Science, Otsu, Japan.,Departments of Cardiovascular Medicine (N.N., M.H.), Shiga University of Medical Science, Otsu, Japan
| | - Koichi Kawakami
- Division of Molecular and Developmental Biology, National Institute of Genetics, Mishima, Japan (K.K.).,Department of Genetics, SOKENDAI (The Graduate University for Advanced Studies), Mishima, Japan (K.K.)
| | - Tetsushi Furukawa
- Department of Bioinformational Pharmacology (T.F.), Tokyo Medical and Dental University, Japan
| | - Akio Koizumi
- Public Interest Foundation Kyoto Hokenkai, Japan (A.K.)
| | - Yoshihisa Kurachi
- Pharmacology (A.I., Y.K.), Osaka University Graduate School of Medicine, Suita, Japan
| | - Yasushi Sakata
- Departments of Cardiovascular Medicine (N.Y., Y.A., A.T., H. Kioka, Y.M., H.S., Y.S.), Osaka University Graduate School of Medicine, Suita, Japan
| | - Tetsuo Minamino
- Department of Cardiorenal and Cerebrovascular Medicine, Faculty of Medicine, Kagawa University, Japan (T. Minamino)
| | - Masafumi Kitakaze
- Clinical Medicine and Development (M.K.), National Cerebral and Cardiovascular Center, Suita, Japan
| | - Seiji Takashima
- Medical Biochemistry (O.T., H. Kato, Y.N., S.T.), Osaka University Graduate School of Medicine, Suita, Japan
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26
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Veerman CC, Mengarelli I, Koopman CD, Wilders R, van Amersfoorth SC, Bakker D, Wolswinkel R, Hababa M, de Boer TP, Guan K, Milnes J, Lodder EM, Bakkers J, Verkerk AO, Bezzina CR. Genetic variation in GNB5 causes bradycardia by augmenting the cholinergic response via increased acetylcholine-activated potassium current ( I K,ACh). Dis Model Mech 2019; 12:dmm.037994. [PMID: 31208990 PMCID: PMC6679373 DOI: 10.1242/dmm.037994] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 06/06/2019] [Indexed: 12/19/2022] Open
Abstract
Mutations in GNB5, encoding the G-protein β5 subunit (Gβ5), have recently been linked to a multisystem disorder that includes severe bradycardia. Here, we investigated the mechanism underlying bradycardia caused by the recessive p.S81L Gβ5 variant. Using CRISPR/Cas9-based targeting, we generated an isogenic series of human induced pluripotent stem cell (hiPSC) lines that were either wild type, heterozygous or homozygous for the GNB5 p.S81L variant. These were differentiated into cardiomyocytes (hiPSC-CMs) that robustly expressed the acetylcholine-activated potassium channel [I(KACh); also known as IK,ACh]. Baseline electrophysiological properties of the lines did not differ. Upon application of carbachol (CCh), homozygous p.S81L hiPSC-CMs displayed an increased acetylcholine-activated potassium current (I K,ACh) density and a more pronounced decrease of spontaneous activity as compared to wild-type and heterozygous p.S81L hiPSC-CMs, explaining the bradycardia in homozygous carriers. Application of the specific I(KACh) blocker XEN-R0703 resulted in near-complete reversal of the phenotype. Our results provide mechanistic insights and proof of principle for potential therapy in patients carrying GNB5 mutations.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Christiaan C Veerman
- Amsterdam UMC, University of Amsterdam, Department of Experimental Cardiology, Heart Center, 1105 AZ Amsterdam, The Netherlands
| | - Isabella Mengarelli
- Amsterdam UMC, University of Amsterdam, Department of Experimental Cardiology, Heart Center, 1105 AZ Amsterdam, The Netherlands
| | - Charlotte D Koopman
- Department of Medical Physiology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands.,Hubrecht Institute, 3584 CT Utrecht, The Netherlands
| | - Ronald Wilders
- Amsterdam UMC, University of Amsterdam, Department of Medical Biology, Heart Failure Research Center, 1105 AZ Amsterdam, The Netherlands
| | - Shirley C van Amersfoorth
- Amsterdam UMC, University of Amsterdam, Department of Experimental Cardiology, Heart Center, 1105 AZ Amsterdam, The Netherlands
| | - Diane Bakker
- Amsterdam UMC, University of Amsterdam, Department of Experimental Cardiology, Heart Center, 1105 AZ Amsterdam, The Netherlands
| | - Rianne Wolswinkel
- Amsterdam UMC, University of Amsterdam, Department of Experimental Cardiology, Heart Center, 1105 AZ Amsterdam, The Netherlands
| | - Mariam Hababa
- Hubrecht Institute, 3584 CT Utrecht, The Netherlands
| | - Teun P de Boer
- Department of Medical Physiology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
| | - Kaomei Guan
- Department of Pharmacology and Toxicology, Technische Universität Dresden, 01062 Dresden, Germany
| | | | - Elisabeth M Lodder
- Amsterdam UMC, University of Amsterdam, Department of Experimental Cardiology, Heart Center, 1105 AZ Amsterdam, The Netherlands
| | - Jeroen Bakkers
- Department of Medical Physiology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands.,Hubrecht Institute, 3584 CT Utrecht, The Netherlands
| | - Arie O Verkerk
- Amsterdam UMC, University of Amsterdam, Department of Experimental Cardiology, Heart Center, 1105 AZ Amsterdam, The Netherlands.,Amsterdam UMC, University of Amsterdam, Department of Medical Biology, Heart Failure Research Center, 1105 AZ Amsterdam, The Netherlands
| | - Connie R Bezzina
- Amsterdam UMC, University of Amsterdam, Department of Experimental Cardiology, Heart Center, 1105 AZ Amsterdam, The Netherlands
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Vo BN, Abney KK, Anderson A, Marron Fernandez de Velasco E, Benneyworth MA, Daniels JS, Morrison RD, Hopkins CR, Weaver CD, Wickman K. VU0810464, a non-urea G protein-gated inwardly rectifying K + (K ir 3/GIRK) channel activator, exhibits enhanced selectivity for neuronal K ir 3 channels and reduces stress-induced hyperthermia in mice. Br J Pharmacol 2019; 176:2238-2249. [PMID: 30924523 DOI: 10.1111/bph.14671] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 02/16/2019] [Accepted: 02/20/2019] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND AND PURPOSE G protein-gated inwardly rectifying K+ (Kir 3) channels moderate the activity of excitable cells and have been implicated in neurological disorders and cardiac arrhythmias. Most neuronal Kir 3 channels consist of Kir 3.1 and Kir 3.2 subtypes, while cardiac Kir 3 channels consist of Kir 3.1 and Kir 3.4 subtypes. Previously, we identified a family of urea-containing Kir 3 channel activators, but these molecules exhibit suboptimal pharmacokinetic properties and modest selectivity for Kir 3.1/3.2 relative to Kir 3.1/3.4 channels. Here, we characterize a non-urea activator, VU0810464, which displays nanomolar potency as a Kir 3.1/3.2 activator, improved selectivity for neuronal Kir 3 channels, and improved brain penetration. EXPERIMENTAL APPROACH We used whole-cell electrophysiology to measure the efficacy and potency of VU0810464 in neurons and the selectivity of VU0810464 for neuronal and cardiac Kir 3 channel subtypes. We tested VU0810464 in vivo in stress-induced hyperthermia and elevated plus maze paradigms. Parallel studies with ML297, the prototypical activator of Kir 3.1-containing Kir 3 channels, were performed to permit direct comparisons. KEY RESULTS VU0810464 and ML297 exhibited comparable efficacy and potency as neuronal Kir 3 channel activators, but VU0810464 was more selective for neuronal Kir 3 channels. VU0810464, like ML297, reduced stress-induced hyperthermia in a Kir 3-dependent manner in mice. ML297, but not VU0810464, decreased anxiety-related behaviour as assessed with the elevated plus maze test. CONCLUSION AND IMPLICATIONS VU0810464 represents a new class of Kir 3 channel activator with enhanced selectivity for Kir 3.1/3.2 channels. VU0810464 may be useful for examining Kir 3.1/3.2 channel contributions to complex behaviours and for probing the potential of Kir 3 channel-dependent manipulations to treat neurological disorders.
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Affiliation(s)
- Baovi N Vo
- Department of Pharmacology, University of Minnesota, Minneapolis, MN
| | - Kristopher K Abney
- School of Graduate Studies and Research, Meharry Medical College, Nashville, TN
| | - Allison Anderson
- Department of Pharmacology, University of Minnesota, Minneapolis, MN
| | | | | | | | - Ryan D Morrison
- Research and Development, Precera Bioscience, Inc., Franklin, TN
| | - Corey R Hopkins
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE
| | | | - Kevin Wickman
- Department of Pharmacology, University of Minnesota, Minneapolis, MN
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28
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Lee SW, Anderson A, Guzman PA, Nakano A, Tolkacheva EG, Wickman K. Atrial GIRK Channels Mediate the Effects of Vagus Nerve Stimulation on Heart Rate Dynamics and Arrhythmogenesis. Front Physiol 2018; 9:943. [PMID: 30072916 PMCID: PMC6060443 DOI: 10.3389/fphys.2018.00943] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 06/27/2018] [Indexed: 01/09/2023] Open
Abstract
Diminished parasympathetic influence is central to the pathogenesis of cardiovascular diseases, including heart failure and hypertension. Stimulation of the vagus nerve has shown promise in treating cardiovascular disease, prompting renewed interest in understanding the signaling pathway(s) that mediate the vagal influence on cardiac physiology. Here, we evaluated the contribution of G protein-gated inwardly rectifying K+ (GIRK/Kir3) channels to the effect of vagus nerve stimulation (VNS) on heart rate (HR), HR variability (HRV), and arrhythmogenesis in anesthetized mice. As parasympathetic fibers innervate both atria and ventricle, and GIRK channels contribute to the cholinergic impact on atrial and ventricular myocytes, we collected in vivo electrocardiogram recordings from mice lacking either atrial or ventricular GIRK channels, during VNS. VNS decreased HR and increased HRV in control mice, in a muscarinic receptor-dependent manner. This effect was preserved in mice lacking ventricular GIRK channels, but was nearly completely absent in mice lacking GIRK channels in the atria. In addition, atrial-specific ablation of GIRK channels conferred resistance to arrhythmic episodes induced by VNS. These data indicate that atrial GIRK channels are the primary mediators of the impact of VNS on HR, HRV, and arrhythmogenesis in the anesthetized mouse.
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Affiliation(s)
- Steven W. Lee
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, United States
| | - Allison Anderson
- Department of Pharmacology, University of Minnesota, Minneapolis, MN, United States
| | - Pilar A. Guzman
- Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis, MN, United States
| | - Atsushi Nakano
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Elena G. Tolkacheva
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, United States
| | - Kevin Wickman
- Department of Pharmacology, University of Minnesota, Minneapolis, MN, United States
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29
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Mesirca P, Torrente AG, Bidaud I, Baudot M, Nargeot J, Mangoni ME. [Genesis of cardiac sinus automaticity and therapeutic perspectives]. ARCHIVES DES MALADIES DU COEUR ET DES VAISSEAUX. PRATIQUE 2018; 2018:35-39. [PMID: 30333689 PMCID: PMC6186439 DOI: 10.1016/j.amcp.2018.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Affiliation(s)
- P Mesirca
- CNRS, Inserm, département de physiologie, université de Montpellier, institut de génomique fonctionnelle, 141, rue de la Cardonille, 34094 Montpellier, France
| | - A-G Torrente
- CNRS, Inserm, département de physiologie, université de Montpellier, institut de génomique fonctionnelle, 141, rue de la Cardonille, 34094 Montpellier, France
| | - I Bidaud
- CNRS, Inserm, département de physiologie, université de Montpellier, institut de génomique fonctionnelle, 141, rue de la Cardonille, 34094 Montpellier, France
| | - M Baudot
- CNRS, Inserm, département de physiologie, université de Montpellier, institut de génomique fonctionnelle, 141, rue de la Cardonille, 34094 Montpellier, France
| | - J Nargeot
- CNRS, Inserm, département de physiologie, université de Montpellier, institut de génomique fonctionnelle, 141, rue de la Cardonille, 34094 Montpellier, France
| | - M-E Mangoni
- CNRS, Inserm, département de physiologie, université de Montpellier, institut de génomique fonctionnelle, 141, rue de la Cardonille, 34094 Montpellier, France
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30
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Verma SS, Josyula N, Verma A, Zhang X, Veturi Y, Dewey FE, Hartzel DN, Lavage DR, Leader J, Ritchie MD, Pendergrass SA. Rare variants in drug target genes contributing to complex diseases, phenome-wide. Sci Rep 2018; 8:4624. [PMID: 29545597 PMCID: PMC5854600 DOI: 10.1038/s41598-018-22834-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 03/01/2018] [Indexed: 12/30/2022] Open
Abstract
The DrugBank database consists of ~800 genes that are well characterized drug targets. This list of genes is a useful resource for association testing. For example, loss of function (LOF) genetic variation has the potential to mimic the effect of drugs, and high impact variation in these genes can impact downstream traits. Identifying novel associations between genetic variation in these genes and a range of diseases can also uncover new uses for the drugs that target these genes. Phenome Wide Association Studies (PheWAS) have been successful in identifying genetic associations across hundreds of thousands of diseases. We have conducted a novel gene based PheWAS to test the effect of rare variants in DrugBank genes, evaluating associations between these genes and more than 500 quantitative and dichotomous phenotypes. We used whole exome sequencing data from 38,568 samples in Geisinger MyCode Community Health Initiative. We evaluated the results of this study when binning rare variants using various filters based on potential functional impact. We identified multiple novel associations, and the majority of the significant associations were driven by functionally annotated variation. Overall, this study provides a sweeping exploration of rare variant associations within functionally relevant genes across a wide range of diagnoses.
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Affiliation(s)
- Shefali Setia Verma
- Perelman School of Medicine, Department of Genetics, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Navya Josyula
- Biomedical and Translational Informatics Institute, Geisinger, Danville, PA, 17221, USA
| | - Anurag Verma
- Perelman School of Medicine, Department of Genetics, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Xinyuan Zhang
- Perelman School of Medicine, Department of Genetics, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Yogasudha Veturi
- Perelman School of Medicine, Department of Genetics, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | | | - Dustin N Hartzel
- Phenomic Analytics and Clinical Data Core, Geisinger, Danville, PA, USA
| | - Daniel R Lavage
- Phenomic Analytics and Clinical Data Core, Geisinger, Danville, PA, USA
| | - Joe Leader
- Biomedical and Translational Informatics Institute, Geisinger, Danville, PA, 17221, USA.,Phenomic Analytics and Clinical Data Core, Geisinger, Danville, PA, USA
| | - Marylyn D Ritchie
- Perelman School of Medicine, Department of Genetics, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Sarah A Pendergrass
- Biomedical and Translational Informatics Institute, Geisinger, Danville, PA, 17221, USA.
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31
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TRPM7 regulates angiotensin II-induced sinoatrial node fibrosis in sick sinus syndrome rats by mediating Smad signaling. Heart Vessels 2018; 33:1094-1105. [PMID: 29511803 PMCID: PMC6096742 DOI: 10.1007/s00380-018-1146-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 03/02/2018] [Indexed: 01/09/2023]
Abstract
Sinoatrial node fibrosis is involved in the pathogenesis of sinus sick syndrome (SSS). Transient receptor potential (TRP) subfamily M member 7 (TRPM7) is implicated in cardiac fibrosis. However, the mechanisms underlying the regulation of sinoatrial node (SAN) fibrosis in SSS by TRPM7 remain unknown. The aim of this study was to investigate the role of angiotensin II (Ang II)/TRPM7/Smad pathway in the SAN fibrosis in rats with SSS. The rat SSS model was established with sodium hydroxide pinpoint pressing permeation. Forty-eight rats were randomly divided into six groups: normal control (ctrl), sham operation (sham), postoperative 1-, 2-, 3-, and 4-week SSS, respectively. The tissue explant culture method was used to culture cardiac fibroblasts (CFs) from rat SAN tissues. TRPM7 siRNA or encoding plasmids were used to knock down or overexpress TRPM7. Collagen (Col) distribution in SAN and atria was assessed using PASM–Masson staining. Ang II, Col I, and Col III levels in serum and tissues or in CFs were determined by ELISA. TRPM7, smad2 and p-smad2 levels were evaluated by real-time PCR, and/or western blot and immunohistochemistry. SAN and atria in rats of the SSS groups had more fibers and higher levels of Ang II, Col I and III than the sham rats. Similar findings were obtained for TRPM7 and pSmad2 expression. In vitro, Ang II promoted CFs collagen synthesis in a dose-dependent manner, and potentiated TRPM7 and p-Smad2 expression. TRPM7 depletion inhibited Ang II-induced p-Smad2 expression and collagen synthesis in CFs, whereas increased TRPM7 expression did the opposite. SAN fibrosis is regulated by the Ang II/TRPM7/Smad pathway in SSS, indicating that TRPM7 is a potential target for SAN fibrosis therapy in SSS.
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32
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Kozasa Y, Nakashima N, Ito M, Ishikawa T, Kimoto H, Ushijima K, Makita N, Takano M. HCN4 pacemaker channels attenuate the parasympathetic response and stabilize the spontaneous firing of the sinoatrial node. J Physiol 2018; 596:809-825. [PMID: 29315578 PMCID: PMC5830425 DOI: 10.1113/jp275303] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Accepted: 01/02/2018] [Indexed: 01/01/2023] Open
Abstract
Key points The contribution of HCN4 pacemaker channels in the autonomic regulation of the sino‐atrial node (SAN) has been a matter of debate. The transgenic overexpression of HCN4 did not induce tachycardia, but reduced heart rate variability, while the conditional knockdown of HCN4 gave rise to sinus arrhythmia. The response of the SAN to β‐adrenergic stimulation was not affected by overexpression or knockdown of HCN4 channels. When HCN4 channels were knocked down, the parasympathetic response examined by cervical vagus nerve stimulation (CVNS) was enhanced; the CVNS induced complete sinus pause. The overexpression of HCN4 attenuated bradycardia induced by CVNS only during β‐adrenergic stimulation. We concluded that HCN4 pacemaker channels stabilize the spontaneous firing by attenuating the parasympathetic response of the SAN.
Abstract The heart rate is dynamically controlled by the sympathetic and parasympathetic nervous systems that regulate the sinoatrial node (SAN). HCN4 pacemaker channels are the well‐known causative molecule of congenital sick sinus syndrome. Although HCN4 channels are activated by cAMP, the sympathetic response of the SAN was preserved in patients carrying loss‐of‐function mutations of the HCN4 gene. In order to clarify the contribution of HCN4 channels in the autonomic regulation of the SAN, we developed novel gain‐of‐function mutant mice in which the expression level of HCN4 channels could be reversibly changed from zero to ∼3 times that in wild‐type mice, using tetracycline transactivator and the tetracycline responsive element. We recorded telemetric ECGs in freely moving conscious mice and analysed the heart rate variability. We also evaluated the response of the SAN to cervical vagus nerve stimulation (CVNS). The conditional overexpression of HCN4 did not induce tachycardia, but reduced heart rate variability. The HCN4 overexpression also attenuated bradycardia induced by the CVNS only during the β‐adrenergic stimulation. In contrast, the knockdown of HCN4 gave rise to sinus arrhythmia, and enhanced the parasympathetic response; complete sinus pause was induced by the CVNS. In vitro, we compared the effects of acetylcholine on the spontaneous action potentials of single pacemaker cells, and found that similar phenotypic changes were induced by genetic manipulation of HCN4 expression both in the presence and absence of β‐adrenergic stimulation. Our study suggests that HCN4 channels attenuate the vagal response of the SAN, and thereby stabilize the spontaneous firing of the SAN. The contribution of HCN4 pacemaker channels in the autonomic regulation of the sino‐atrial node (SAN) has been a matter of debate. The transgenic overexpression of HCN4 did not induce tachycardia, but reduced heart rate variability, while the conditional knockdown of HCN4 gave rise to sinus arrhythmia. The response of the SAN to β‐adrenergic stimulation was not affected by overexpression or knockdown of HCN4 channels. When HCN4 channels were knocked down, the parasympathetic response examined by cervical vagus nerve stimulation (CVNS) was enhanced; the CVNS induced complete sinus pause. The overexpression of HCN4 attenuated bradycardia induced by CVNS only during β‐adrenergic stimulation. We concluded that HCN4 pacemaker channels stabilize the spontaneous firing by attenuating the parasympathetic response of the SAN.
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Affiliation(s)
- Yuko Kozasa
- Department of Physiology, Kurume University School of Medicine, 67 Asahi-Machi, Kurume, 830-0011, Japan.,Department of Anesthesiology, Kurume University School of Medicine, 67 Asahi-Machi, Kurume, 830-0011, Japan
| | - Noriyuki Nakashima
- Department of Physiology, Kurume University School of Medicine, 67 Asahi-Machi, Kurume, 830-0011, Japan
| | - Masayuki Ito
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, 187-8502, Japan
| | - Taisuke Ishikawa
- Department of Molecular Physiology, Nagasaki University, Graduate School of Biomedical Sciences, 1-12-4, Sakamoto, Nagasaki, 852-8523, Japan
| | - Hiroki Kimoto
- Department of Molecular Physiology, Nagasaki University, Graduate School of Biomedical Sciences, 1-12-4, Sakamoto, Nagasaki, 852-8523, Japan
| | - Kazuo Ushijima
- Department of Anesthesiology, Kurume University School of Medicine, 67 Asahi-Machi, Kurume, 830-0011, Japan
| | - Naomasa Makita
- Department of Molecular Physiology, Nagasaki University, Graduate School of Biomedical Sciences, 1-12-4, Sakamoto, Nagasaki, 852-8523, Japan
| | - Makoto Takano
- Department of Physiology, Kurume University School of Medicine, 67 Asahi-Machi, Kurume, 830-0011, Japan
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33
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Expression and relevance of the G protein-gated K + channel in the mouse ventricle. Sci Rep 2018; 8:1192. [PMID: 29352184 PMCID: PMC5775354 DOI: 10.1038/s41598-018-19719-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 01/08/2018] [Indexed: 12/31/2022] Open
Abstract
The atrial G protein-gated inwardly rectifying K+ (GIRK) channel is a critical mediator of parasympathetic influence on cardiac physiology. Here, we probed the details and relevance of the GIRK channel in mouse ventricle. mRNAs for the atrial GIRK channel subunits (GIRK1, GIRK4), M2 muscarinic receptor (M2R), and RGS6, a negative regulator of atrial GIRK-dependent signaling, were detected in mouse ventricle at relatively low levels. The cholinergic agonist carbachol (CCh) activated small GIRK currents in adult wild-type ventricular myocytes that exhibited relatively slow kinetics and low CCh sensitivity; these currents were absent in ventricular myocytes from Girk1-/- or Girk4-/- mice. While loss of GIRK channels attenuated the CCh-induced shortening of action potential duration and suppression of ventricular myocyte excitability, selective ablation of GIRK channels in ventricle had no effect on heart rate, heart rate variability, or electrocardiogram parameters at baseline or after CCh injection. Additionally, loss of ventricular GIRK channels did not impact susceptibility to ventricular arrhythmias. These data suggest that the mouse ventricular GIRK channel is a GIRK1/GIRK4 heteromer, and show that while it contributes to the cholinergic suppression of ventricular myocyte excitability, this influence does not substantially impact cardiac physiology or ventricular arrhythmogenesis in the mouse.
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34
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Aziz Q, Li Y, Tinker A. Potassium channels in the sinoatrial node and their role in heart rate control. Channels (Austin) 2018; 12:356-366. [PMID: 30301404 PMCID: PMC6207292 DOI: 10.1080/19336950.2018.1532255] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 09/25/2018] [Accepted: 09/28/2018] [Indexed: 10/28/2022] Open
Abstract
Potassium currents determine the resting membrane potential and govern repolarisation in cardiac myocytes. Here, we review the various currents in the sinoatrial node focussing on their molecular and cellular properties and their role in pacemaking and heart rate control. We also describe how our recent finding of a novel ATP-sensitive potassium channel population in these cells fits into this picture.
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Affiliation(s)
- Qadeer Aziz
- William Harvey Heart Centre, Barts & The London School of Medicine & Dentistry, Queen Mary, University of London, London, UK
| | - Yiwen Li
- William Harvey Heart Centre, Barts & The London School of Medicine & Dentistry, Queen Mary, University of London, London, UK
| | - Andrew Tinker
- William Harvey Heart Centre, Barts & The London School of Medicine & Dentistry, Queen Mary, University of London, London, UK
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35
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Haron-Khun S, Weisbrod D, Bueno H, Yadin D, Behar J, Peretz A, Binah O, Hochhauser E, Eldar M, Yaniv Y, Arad M, Attali B. SK4 K + channels are therapeutic targets for the treatment of cardiac arrhythmias. EMBO Mol Med 2017; 9:415-429. [PMID: 28219898 PMCID: PMC5376763 DOI: 10.15252/emmm.201606937] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a stress‐provoked ventricular arrhythmia, which also manifests sinoatrial node (SAN) dysfunction. We recently showed that SK4 calcium‐activated potassium channels are important for automaticity of cardiomyocytes derived from human embryonic stem cells. Here SK4 channels were identified in human induced pluripotent stem cell‐derived cardiomyocytes (hiPSC‐CMs) from healthy and CPVT2 patients bearing a mutation in calsequestrin 2 (CASQ2‐D307H) and in SAN cells from WT and CASQ2‐D307H knock‐in (KI) mice. TRAM‐34, a selective blocker of SK4 channels, prominently reduced delayed afterdepolarizations and arrhythmic Ca2+ transients observed following application of the β‐adrenergic agonist isoproterenol in CPVT2‐derived hiPSC‐CMs and in SAN cells from KI mice. Strikingly, in vivo ECG recording showed that intraperitoneal injection of the SK4 channel blockers, TRAM‐34 or clotrimazole, greatly reduced the arrhythmic features of CASQ2‐D307H KI and CASQ2 knockout mice at rest and following exercise. This work demonstrates the critical role of SK4 Ca2+‐activated K+ channels in adult pacemaker function, making them promising therapeutic targets for the treatment of cardiac ventricular arrhythmias such as CPVT.
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Affiliation(s)
- Shiraz Haron-Khun
- Department of Physiology and Pharmacology, The Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Leviev Heart Center, Sheba Medical Center, Tel Hashomer, Tel Aviv, Israel
| | - David Weisbrod
- Department of Physiology and Pharmacology, The Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Hanna Bueno
- Department of Physiology and Pharmacology, The Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Dor Yadin
- Leviev Heart Center, Sheba Medical Center, Tel Hashomer, Tel Aviv, Israel
| | - Joachim Behar
- Laboratory of Bioenergetic and Bioelectric Systems, Biomedical Engineering Faculty, Technion-Israel Institute of Technology, Haifa, Israel
| | - Asher Peretz
- Department of Physiology and Pharmacology, The Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ofer Binah
- Department of Physiology, Ruth & Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
| | - Edith Hochhauser
- The Cardiac Research Laboratory of the Department of Cardiothoracic Surgery, Felsenstein Medical Research Center, Rabin Medical Center, Tel Aviv University, Petah Tikva, Israel
| | - Michael Eldar
- Leviev Heart Center, Sheba Medical Center, Tel Hashomer, Tel Aviv, Israel
| | - Yael Yaniv
- Laboratory of Bioenergetic and Bioelectric Systems, Biomedical Engineering Faculty, Technion-Israel Institute of Technology, Haifa, Israel
| | - Michael Arad
- Leviev Heart Center, Sheba Medical Center, Tel Hashomer, Tel Aviv, Israel
| | - Bernard Attali
- Department of Physiology and Pharmacology, The Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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36
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Temple IP, Logantha SJRJ, Absi M, Zhang Y, Pervolaraki E, Yanni J, Atkinson A, Petkova M, Quigley GM, Castro S, Drinkhill M, Schneider H, Monfredi O, Cartwright E, Zi M, Yamanushi TT, Mahadevan VS, Gurney AM, White E, Zhang H, Hart G, Boyett MR, Dobrzynski H. Atrioventricular Node Dysfunction and Ion Channel Transcriptome in Pulmonary Hypertension. Circ Arrhythm Electrophysiol 2017; 9:CIRCEP.115.003432. [PMID: 27979911 DOI: 10.1161/circep.115.003432] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 11/10/2016] [Indexed: 01/18/2023]
Abstract
BACKGROUND Heart block is associated with pulmonary hypertension, and the aim of the study was to test the hypothesis that the heart block is the result of a change in the ion channel transcriptome of the atrioventricular (AV) node. METHODS AND RESULTS The most commonly used animal model of pulmonary hypertension, the monocrotaline-injected rat, was used. The functional consequences of monocrotaline injection were determined by echocardiography, ECG recording, and electrophysiological experiments on the Langendorff-perfused heart and isolated AV node. The ion channel transcriptome was measured by quantitative PCR, and biophysically detailed computer modeling was used to explore the changes observed. After monocrotaline injection, echocardiography revealed the pattern of pulmonary artery blood flow characteristic of pulmonary hypertension and right-sided hypertrophy and failure; the Langendorff-perfused heart and isolated AV node revealed dysfunction of the AV node (eg, 50% incidence of heart block in isolated AV node); and quantitative PCR revealed a widespread downregulation of ion channel and related genes in the AV node (eg, >50% downregulation of Cav1.2/3 and HCN1/2/4 channels). Computer modeling predicted that the changes in the transcriptome if translated into protein and function would result in heart block. CONCLUSIONS Pulmonary hypertension results in a derangement of the ion channel transcriptome in the AV node, and this is the likely cause of AV node dysfunction in this disease.
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Affiliation(s)
- Ian P Temple
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Sunil Jit R J Logantha
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Mais Absi
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Yu Zhang
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Eleftheria Pervolaraki
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Joseph Yanni
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Andrew Atkinson
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Maria Petkova
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Gillian M Quigley
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Simon Castro
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Mark Drinkhill
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Heiko Schneider
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Oliver Monfredi
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Elizabeth Cartwright
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Min Zi
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Tomoko T Yamanushi
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Vaikom S Mahadevan
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Alison M Gurney
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Ed White
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Henggui Zhang
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - George Hart
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
| | - Mark R Boyett
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.).
| | - Halina Dobrzynski
- From the Institute of Cardiovascular Sciences (I.P.T., S.J.R.J.L., M.A., Y.Z., J.Y., A.A., M.P., G.M.Q., H.S., O.M., E.C., M.Z., A.M.G., G.H., M.R.B., H.D.) and School of Physics and Astronomy (S.C., H.Z.), University of Manchester, United Kingdom; School of Biomedical Sciences, University of Leeds, United Kingdom (E.P., M.D., E.W.); Kagawa Prefectural College of Health Sciences, Takamatsu, Japan (T.T.Y.); and Department of Medicine, University of California, San Francisco (V.S.M.)
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Lodder EM, Verkerk AO, Bezzina CR. Pacing Discovery: G-Protein β Subunit Mutations in Sinus Node Dysfunction. Circ Res 2017; 120:1524-1526. [PMID: 28495981 DOI: 10.1161/circresaha.117.310953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Elisabeth M Lodder
- From the Heart Center, Department of Clinical and Experimental Cardiology (E.M.L., A.O.V., C.R.B.) and Department of Medical Biology (A.O.V.), Academic Medical Center, Amsterdam, the Netherlands
| | - Arie O Verkerk
- From the Heart Center, Department of Clinical and Experimental Cardiology (E.M.L., A.O.V., C.R.B.) and Department of Medical Biology (A.O.V.), Academic Medical Center, Amsterdam, the Netherlands
| | - Connie R Bezzina
- From the Heart Center, Department of Clinical and Experimental Cardiology (E.M.L., A.O.V., C.R.B.) and Department of Medical Biology (A.O.V.), Academic Medical Center, Amsterdam, the Netherlands.
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Stallmeyer B, Kuß J, Kotthoff S, Zumhagen S, Vowinkel K, Rinné S, Matschke LA, Friedrich C, Schulze-Bahr E, Rust S, Seebohm G, Decher N, Schulze-Bahr E. A Mutation in the G-Protein Gene GNB2 Causes Familial Sinus Node and Atrioventricular Conduction Dysfunction. Circ Res 2017; 120:e33-e44. [PMID: 28219978 DOI: 10.1161/circresaha.116.310112] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 02/16/2017] [Accepted: 02/20/2017] [Indexed: 11/16/2022]
Abstract
RATIONALE Familial sinus node and atrioventricular conduction dysfunction is a rare disorder that leads to paroxysmal dizziness, fatigue, and syncope because of a temporarily or permanently reduced heart rate. To date, only a few genes for familial sinus and atrioventricular conduction dysfunction are known, and the majority of cases remain pathogenically unresolved. OBJECTIVE We aim to identify the disease gene in a large 3-generation family (n=25) with autosomal dominant sinus node dysfunction (SND) and atrioventricular block (AVB) and to characterize the mutation-related pathomechanisms in familial SND+AVB. METHODS AND RESULTS Genome-wide linkage analysis mapped the SND+AVB disease locus to chromosome 7q21.1-q31.1 (2-point logarithm of the odds score: 4.64; θ=0); in this region, targeted exome sequencing identified a novel heterozygous mutation (p.Arg52Leu) in the GNB2 gene that strictly cosegregated with the SND+AVB phenotype. GNB2 encodes the β2 subunit (Gβ2) of the heterotrimeric G-protein complex that is being released from G-protein-coupled receptors on vagal stimulation. In 2 heterologous expression systems (HEK-293T cells and Xenopus laevis oocytes), an enhanced activation of the G-protein-activated K+ channel (GIRK; Kir3.1/Kir3.4) was shown when mutant Gβ2 was coexpressed with Gγ2; this was in contrast to coexpression of mutant Gβ2-Gγ2 with other cardiac ion channels (HCN4, HCN2, and Cav1.2). Molecular dynamics simulations suggested a reduced binding property of mutant Gβ2 to cardiac GIRK channels when compared with native Gβ2. CONCLUSIONS A GNB2 gene mutation is associated with familial SND+AVB and leads to a sustained activation of cardiac GIRK channels, which is likely to hyperpolarize the myocellular membrane potential and thus reduces their spontaneous activity. Our findings describe for the first time a role of a mutant G-protein in the nonsyndromic pacemaker disease because of GIRK channel activation.
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Affiliation(s)
- Birgit Stallmeyer
- From the Institute for Genetics of Heart Diseases, Department of Cardiology and Angiology, University Hospital Muenster, Germany (B.S., J.K., S.Z., C.F., E.S.-B., G.S., E.S.-B.); Department of Pediatric Cardiology (S.K.) and Department of General Pediatrics (S.R.), University Children's Hospital Muenster, Germany; and Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps University of Marburg, Germany (K.V., S.R., L.A.M., N.D.)
| | - Johanna Kuß
- From the Institute for Genetics of Heart Diseases, Department of Cardiology and Angiology, University Hospital Muenster, Germany (B.S., J.K., S.Z., C.F., E.S.-B., G.S., E.S.-B.); Department of Pediatric Cardiology (S.K.) and Department of General Pediatrics (S.R.), University Children's Hospital Muenster, Germany; and Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps University of Marburg, Germany (K.V., S.R., L.A.M., N.D.)
| | - Stefan Kotthoff
- From the Institute for Genetics of Heart Diseases, Department of Cardiology and Angiology, University Hospital Muenster, Germany (B.S., J.K., S.Z., C.F., E.S.-B., G.S., E.S.-B.); Department of Pediatric Cardiology (S.K.) and Department of General Pediatrics (S.R.), University Children's Hospital Muenster, Germany; and Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps University of Marburg, Germany (K.V., S.R., L.A.M., N.D.)
| | - Sven Zumhagen
- From the Institute for Genetics of Heart Diseases, Department of Cardiology and Angiology, University Hospital Muenster, Germany (B.S., J.K., S.Z., C.F., E.S.-B., G.S., E.S.-B.); Department of Pediatric Cardiology (S.K.) and Department of General Pediatrics (S.R.), University Children's Hospital Muenster, Germany; and Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps University of Marburg, Germany (K.V., S.R., L.A.M., N.D.)
| | - Kirsty Vowinkel
- From the Institute for Genetics of Heart Diseases, Department of Cardiology and Angiology, University Hospital Muenster, Germany (B.S., J.K., S.Z., C.F., E.S.-B., G.S., E.S.-B.); Department of Pediatric Cardiology (S.K.) and Department of General Pediatrics (S.R.), University Children's Hospital Muenster, Germany; and Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps University of Marburg, Germany (K.V., S.R., L.A.M., N.D.)
| | - Susanne Rinné
- From the Institute for Genetics of Heart Diseases, Department of Cardiology and Angiology, University Hospital Muenster, Germany (B.S., J.K., S.Z., C.F., E.S.-B., G.S., E.S.-B.); Department of Pediatric Cardiology (S.K.) and Department of General Pediatrics (S.R.), University Children's Hospital Muenster, Germany; and Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps University of Marburg, Germany (K.V., S.R., L.A.M., N.D.)
| | - Lina A Matschke
- From the Institute for Genetics of Heart Diseases, Department of Cardiology and Angiology, University Hospital Muenster, Germany (B.S., J.K., S.Z., C.F., E.S.-B., G.S., E.S.-B.); Department of Pediatric Cardiology (S.K.) and Department of General Pediatrics (S.R.), University Children's Hospital Muenster, Germany; and Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps University of Marburg, Germany (K.V., S.R., L.A.M., N.D.)
| | - Corinna Friedrich
- From the Institute for Genetics of Heart Diseases, Department of Cardiology and Angiology, University Hospital Muenster, Germany (B.S., J.K., S.Z., C.F., E.S.-B., G.S., E.S.-B.); Department of Pediatric Cardiology (S.K.) and Department of General Pediatrics (S.R.), University Children's Hospital Muenster, Germany; and Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps University of Marburg, Germany (K.V., S.R., L.A.M., N.D.)
| | - Ellen Schulze-Bahr
- From the Institute for Genetics of Heart Diseases, Department of Cardiology and Angiology, University Hospital Muenster, Germany (B.S., J.K., S.Z., C.F., E.S.-B., G.S., E.S.-B.); Department of Pediatric Cardiology (S.K.) and Department of General Pediatrics (S.R.), University Children's Hospital Muenster, Germany; and Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps University of Marburg, Germany (K.V., S.R., L.A.M., N.D.)
| | - Stephan Rust
- From the Institute for Genetics of Heart Diseases, Department of Cardiology and Angiology, University Hospital Muenster, Germany (B.S., J.K., S.Z., C.F., E.S.-B., G.S., E.S.-B.); Department of Pediatric Cardiology (S.K.) and Department of General Pediatrics (S.R.), University Children's Hospital Muenster, Germany; and Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps University of Marburg, Germany (K.V., S.R., L.A.M., N.D.)
| | - Guiscard Seebohm
- From the Institute for Genetics of Heart Diseases, Department of Cardiology and Angiology, University Hospital Muenster, Germany (B.S., J.K., S.Z., C.F., E.S.-B., G.S., E.S.-B.); Department of Pediatric Cardiology (S.K.) and Department of General Pediatrics (S.R.), University Children's Hospital Muenster, Germany; and Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps University of Marburg, Germany (K.V., S.R., L.A.M., N.D.)
| | - Niels Decher
- From the Institute for Genetics of Heart Diseases, Department of Cardiology and Angiology, University Hospital Muenster, Germany (B.S., J.K., S.Z., C.F., E.S.-B., G.S., E.S.-B.); Department of Pediatric Cardiology (S.K.) and Department of General Pediatrics (S.R.), University Children's Hospital Muenster, Germany; and Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps University of Marburg, Germany (K.V., S.R., L.A.M., N.D.)
| | - Eric Schulze-Bahr
- From the Institute for Genetics of Heart Diseases, Department of Cardiology and Angiology, University Hospital Muenster, Germany (B.S., J.K., S.Z., C.F., E.S.-B., G.S., E.S.-B.); Department of Pediatric Cardiology (S.K.) and Department of General Pediatrics (S.R.), University Children's Hospital Muenster, Germany; and Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps University of Marburg, Germany (K.V., S.R., L.A.M., N.D.).
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Mesirca P, Bidaud I, Mangoni ME. Rescuing cardiac automaticity in L-type Cav1.3 channelopathies and beyond. J Physiol 2016; 594:5869-5879. [PMID: 27374078 DOI: 10.1113/jp270678] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2016] [Accepted: 06/24/2016] [Indexed: 11/08/2022] Open
Abstract
Pacemaker activity of the sino-atrial node generates the heart rate. Disease of the sinus node and impairment of atrioventricular conduction induce an excessively low ventricular rate (bradycardia), which cannot meet the needs of the organism. Bradycardia accounts for about half of the total workload of clinical cardiologists. The 'sick sinus' syndrome (SSS) is characterized by sinus bradycardia and periods of intermittent atrial fibrillation. Several genetic or acquired risk factors or pathologies can lead to SSS. Implantation of an electronic pacemaker constitutes the only available therapy for SSS. The incidence of SSS is forecast to double over the next 50 years, with ageing of the general population thus urging the development of complementary or alternative therapeutic strategies. In recent years an increasing number of mutations affecting ion channels involved in sino-atrial automaticity have been reported to underlie inheritable SSS. L-type Cav 1.3 channels play a major role in the generation and regulation of sino-atrial pacemaker activity and atrioventricular conduction. Mutation in the CACNA1D gene encoding Cav 1.3 channels induces loss-of-function in channel activity and underlies the sino-atrial node dysfunction and deafness syndrome (SANDD). Mice lacking Cav 1.3 channels (Cav 1.3-/- ) fairly recapitulate SSS and constitute a precious model to test new therapeutic approaches to handle this disease. Work in our laboratory shows that targeting G protein-gated K+ (IKACh ) channels effectively rescues SSS of Cav 1.3-/- mice. This new concept of 'compensatory' ion channel targeting shines new light on the principles underlying the pacemaker mechanism and may open the way to new therapies for SSS.
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Affiliation(s)
- Pietro Mesirca
- Département de Physiologie, Institut de Genomique Fonctionnelle, LabEx ICST, UMR-5203, Centre national de la recherche scientifique, F-34094, Montpellier, France. .,INSERM U1191, F-34094, Montpellier, France. .,Université de Montpellier, F-34094, Montpellier, France.
| | - Isabelle Bidaud
- Département de Physiologie, Institut de Genomique Fonctionnelle, LabEx ICST, UMR-5203, Centre national de la recherche scientifique, F-34094, Montpellier, France.,INSERM U1191, F-34094, Montpellier, France.,Université de Montpellier, F-34094, Montpellier, France
| | - Matteo E Mangoni
- Département de Physiologie, Institut de Genomique Fonctionnelle, LabEx ICST, UMR-5203, Centre national de la recherche scientifique, F-34094, Montpellier, France. .,INSERM U1191, F-34094, Montpellier, France. .,Université de Montpellier, F-34094, Montpellier, France.
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