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Si M, Darvish A, Paulhus K, Kumar P, Hamilton KA, Glasscock E. Epilepsy-associated Kv1.1 channel subunits regulate intrinsic cardiac pacemaking in mice. J Gen Physiol 2024; 156:e202413578. [PMID: 39037413 PMCID: PMC11261506 DOI: 10.1085/jgp.202413578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 05/11/2024] [Accepted: 07/03/2024] [Indexed: 07/23/2024] Open
Abstract
The heartbeat originates from spontaneous action potentials in specialized pacemaker cells within the sinoatrial node (SAN) of the right atrium. Voltage-gated potassium channels in SAN myocytes mediate outward K+ currents that regulate cardiac pacemaking by controlling action potential repolarization, influencing the time between heartbeats. Gene expression studies have identified transcripts for many types of voltage-gated potassium channels in the SAN, but most remain of unknown functional significance. One such gene is Kcna1, which encodes epilepsy-associated voltage-gated Kv1.1 K+ channel α-subunits that are important for regulating action potential firing in neurons and cardiomyocytes. Here, we investigated the functional contribution of Kv1.1 to cardiac pacemaking at the whole heart, SAN, and SAN myocyte levels by performing Langendorff-perfused isolated heart preparations, multielectrode array recordings, patch clamp electrophysiology, and immunocytochemistry using Kcna1 knockout (KO) and wild-type (WT) mice. Our results showed that either genetic or pharmacological ablation of Kv1.1 significantly decreased the SAN firing rate, primarily by impairing SAN myocyte action potential repolarization. Voltage-clamp electrophysiology and immunocytochemistry revealed that Kv1.1 exerts its effects despite contributing only a small outward K+ current component, which we term IKv1.1, and despite apparently being present in low abundance at the protein level in SAN myocytes. These findings establish Kv1.1 as the first identified member of the Kv1 channel family to play a role in sinoatrial function, thereby rendering it a potential candidate and therapeutic targeting of sinus node dysfunction. Furthermore, our results demonstrate that small currents generated via low-abundance channels can still have significant impacts on cardiac pacemaking.
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Affiliation(s)
- Man Si
- Department of Biological Sciences, Southern Methodist University, Dallas, TX, USA
| | - Ahmad Darvish
- School of Biological and Physical Science, Northwestern State University, Natchitoches, LA, USA
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, Shreveport, Shreveport, LA, USA
| | - Kelsey Paulhus
- Department of Biological Sciences, Southern Methodist University, Dallas, TX, USA
| | - Praveen Kumar
- Department of Biological Sciences, Southern Methodist University, Dallas, TX, USA
| | - Kathryn A. Hamilton
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, Shreveport, Shreveport, LA, USA
| | - Edward Glasscock
- Department of Biological Sciences, Southern Methodist University, Dallas, TX, USA
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, Shreveport, Shreveport, LA, USA
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2
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Boulgakoff L, D'Amato G, Miquerol L. Molecular Regulation of Cardiac Conduction System Development. Curr Cardiol Rep 2024; 26:943-952. [PMID: 38990492 DOI: 10.1007/s11886-024-02094-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/02/2024] [Indexed: 07/12/2024]
Abstract
PURPOSE OF REVIEW The cardiac conduction system, composed of pacemaker cells and conducting cardiomyocytes, orchestrates the propagation of electrical activity to synchronize heartbeats. The conduction system plays a crucial role in the development of cardiac arrhythmias. In the embryo, the cells of the conduction system derive from the same cardiac progenitors as the contractile cardiomyocytes and and the key question is how this choice is made during development. RECENT FINDINGS This review focuses on recent advances in developmental biology using the mouse as animal model to better understand the cellular origin and molecular regulations that control morphogenesis of the cardiac conduction system, including the latest findings in single-cell transcriptomics. The conducting cell fate is acquired during development starting with pacemaking activity and last with the formation of a complex fast-conducting network. Cardiac conduction system morphogenesis is controlled by complex transcriptional and gene regulatory networks that differ in the components of the cardiac conduction system.
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Affiliation(s)
| | - Gaetano D'Amato
- Aix-Marseille Université, CNRS IBDM UMR7288, Marseille, France
| | - Lucile Miquerol
- Aix-Marseille Université, CNRS IBDM UMR7288, Marseille, France.
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3
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Oh Y, Abid R, Dababneh S, Bakr M, Aslani T, Cook DP, Vanderhyden BC, Park JG, Munshi NV, Hui CC, Kim KH. Transcriptional regulation of the postnatal cardiac conduction system heterogeneity. Nat Commun 2024; 15:6550. [PMID: 39095365 PMCID: PMC11297185 DOI: 10.1038/s41467-024-50849-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 07/23/2024] [Indexed: 08/04/2024] Open
Abstract
The cardiac conduction system (CCS) is a network of specialized cardiomyocytes that coordinates electrical impulse generation and propagation for synchronized heart contractions. Although the components of the CCS, including the sinoatrial node, atrioventricular node, His bundle, bundle branches, and Purkinje fibers, were anatomically discovered more than 100 years ago, their molecular constituents and regulatory mechanisms remain incompletely understood. Here, we demonstrate the transcriptomic landscape of the postnatal mouse CCS at a single-cell resolution with spatial information. Integration of single-cell and spatial transcriptomics uncover region-specific markers and zonation patterns of expression. Network inference shows heterogeneous gene regulatory networks across the CCS. Notably, region-specific gene regulation is recapitulated in vitro using neonatal mouse atrial and ventricular myocytes overexpressing CCS-specific transcription factors, Tbx3 and/or Irx3. This finding is supported by ATAC-seq of different CCS regions, Tbx3 ChIP-seq, and Irx motifs. Overall, this study provides comprehensive molecular profiles of the postnatal CCS and elucidates gene regulatory mechanisms contributing to its heterogeneity.
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Affiliation(s)
- Yena Oh
- University of Ottawa Heart Institute, Ottawa, ON, Canada
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Rimshah Abid
- University of Ottawa Heart Institute, Ottawa, ON, Canada
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Saif Dababneh
- University of Ottawa Heart Institute, Ottawa, ON, Canada
- Department of Cellular and Physiological Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Marwan Bakr
- University of Ottawa Heart Institute, Ottawa, ON, Canada
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON, Canada
| | - Termeh Aslani
- University of Ottawa Heart Institute, Ottawa, ON, Canada
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - David P Cook
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Barbara C Vanderhyden
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Jin G Park
- Virginia G. Piper Center for Personalized Diagnostics, Biodesign Institute, Arizona State University, Tempe, AZ, USA
| | - Nikhil V Munshi
- Department of Internal Medicine, Division of Cardiology, UT Southwestern Medical Center, Dallas, TX, USA
- Department of Molecular Biology, UT Southwestern Medical Center, Dallas, TX, USA
- McDermott Center for Human Growth and Development, UT Southwestern Medical Center, Dallas, TX, USA
- Center for Regenerative Science and Medicine, UT Southwestern Medical Center, Dallas, TX, USA
| | - Chi-Chung Hui
- Program in Developmental & Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Kyoung-Han Kim
- University of Ottawa Heart Institute, Ottawa, ON, Canada.
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada.
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4
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Lin WC, Peng PS, Lin SL. Feasibility of Short-Term Use of Ivabradine in Critical Ill Patients Who Have Atrial Fibrillation and Tachycardia. ACTA CARDIOLOGICA SINICA 2024; 40:373-382. [PMID: 39045379 PMCID: PMC11261355 DOI: 10.6515/acs.202407_40(4).20240411a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Accepted: 04/11/2024] [Indexed: 07/25/2024]
Abstract
Background Ivabradine is approved for heart rate reduction in patients with stable symptomatic heart failure (HF). The United States Food and Drug Administration and Taiwan Central Health Insurance Agency approved the use of ivabradine for patients with chronic stable HF with sinus rhythm, but it has not yet been approved for patients with acute decompensated HF or with atrial fibrillation (AF). Objectives To investigate whether short-term ivabradine use is feasible in critically ill patients with AF and rapid ventricular response (RVR). Methods This study retrospectively analyzed 23 patients admitted to an intensive care unit with acute HF and AF-RVR who received ivabradine. All patients initially received a slow IV of amiodarone. Other medications for HF were prescribed according to current HF guidelines. The time taken for ivabradine to reduce HR to 80 beats per minute, referred to as "Time to 80," was measured in each patient. Results Overall, 69.6 % (16/23) of the patients had New York Heart Association functional class IV HF. In addition, 60.9% (14/23) of the patients required endotracheal intubation and ventilatory support, with more than half receiving vasopressor treatment to manage hypotension. Five patients died during the study period. The surviving patients had a significantly shorter "Time to 80" compared to those who did not survive (p = 0.037). Conclusions Adding ivabradine to standard treatment might be feasible for critically ill patients with AF and tachycardia. The finding that surviving patients had a shorter "Time to 80" duration than those who did not survive may have clinical implications. However, further investigations are needed to assess its clinical utility.
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Affiliation(s)
- Wei-Cheng Lin
- Division of Cardiology, Department of Internal Medicine, Kaohsiung Yuan’s General Hospital
| | - Po-Sen Peng
- Division of Cardiology, Department of Internal Medicine, Zuoying Branch of Kaohsiung Armed Forces General Hospital, Kaohsiung
- School of Medicine, National Defense Medical Center, Taipei
| | - Shoa-Lin Lin
- Coronary Care Unit, Division of Cardiology, Department of Internal Medicine, Kaohsiung Yuan’s General Hospital, Kaohsiung, Taiwan
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5
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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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6
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Landi S, Giannetti F, Benzoni P, Campostrini G, Rossi G, Piantoni C, Bertoli G, Bonfanti C, Carnevali L, Bucchi A, Baruscotti M, Careccia G, Messina G, Barbuti A. Lack of the transcription factor Nfix causes tachycardia in mice sinus node and rats neonatal cardiomyocytes. Acta Physiol (Oxf) 2023; 239:e13981. [PMID: 37186371 DOI: 10.1111/apha.13981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 04/20/2023] [Accepted: 04/23/2023] [Indexed: 05/17/2023]
Abstract
AIMS Nfix is a transcription factor belonging to the Nuclear Factor I (NFI) family comprising four members (Nfia, b, c, x). Nfix plays important roles in the development and function of several organs. In muscle development, Nfix controls the switch from embryonic to fetal myogenesis by promoting fast twitching fibres. In the adult muscle, following injury, lack of Nfix impairs regeneration, inducing higher content of slow-twitching fibres. Nfix is expressed also in the heart, but its function has been never investigated before. We studied Nfix role in this organ. METHODS Using Nfix-null and wild type (WT) mice we analyzed: (1) the expression pattern of Nfix during development by qPCR and (2) the functional alterations caused by its absence, by in vivo telemetry and in vitro patch clamp analysis. RESULTS AND CONCLUSIONS Nfix expression start in the heart from E12.5. Adult hearts of Nfix-null mice show a hearts morphology and sarcomeric proteins expression similar to WT. However, Nfix-null animals show tachycardia that derives form an intrinsic higher beating rate of the sinus node (SAN). Molecular and functional analysis revealed that sinoatrial cells of Nfix-null mice express a significantly larger L-type calcium current (Cacna1d + Cacna1c). Interestingly, downregulation of Nfix by sh-RNA in primary cultures of neonatal rat ventricular cardiomyocytes induced a similar increase in their spontaneous beating rate and in ICaL current. In conclusion, our data provide the first demonstration of a role of Nfix that, increasing the L-type calcium current, modulates heart rate.
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Affiliation(s)
- Sara Landi
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Federica Giannetti
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Patrizia Benzoni
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Giulia Campostrini
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Giuliana Rossi
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Chiara Piantoni
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Giorgia Bertoli
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Chiara Bonfanti
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Luca Carnevali
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Annalisa Bucchi
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Mirko Baruscotti
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Giorgia Careccia
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Graziella Messina
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Andrea Barbuti
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Milan, Italy
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7
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Brofiga M, Losacco S, Poggio F, Zerbo RA, Milanese M, Massobrio P, Burlando B. Multiple neuron clusters on Micro-Electrode Arrays as an in vitro model of brain network. Sci Rep 2023; 13:15604. [PMID: 37730890 PMCID: PMC10511538 DOI: 10.1038/s41598-023-42168-0] [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: 02/07/2023] [Accepted: 09/06/2023] [Indexed: 09/22/2023] Open
Abstract
Understanding the brain functioning is essential for governing brain processes with the aim of managing pathological network dysfunctions. Due to the morphological and biochemical complexity of the central nervous system, the development of general models with predictive power must start from in vitro brain network engineering. In the present work, we realized a micro-electrode array (MEA)-based in vitro brain network and studied its emerging dynamical properties. We obtained four-neuron-clusters (4N) assemblies by plating rat embryo cortical neurons on 60-electrode MEA with cross-shaped polymeric masks and compared the emerging dynamics with those of sister single networks (1N). Both 1N and 4N assemblies exhibited spontaneous electrical activity characterized by spiking and bursting signals up to global activation by means of network bursts. Data revealed distinct patterns of network activity with differences between 1 and 4N. Rhythmic network bursts and dominant initiator clusters suggested pacemaker activities in both assembly types, but the propagation of activation sequences was statistically influenced by the assembly topology. We proved that this rhythmic activity was ivabradine sensitive, suggesting the involvement of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, and propagated across the real clusters of 4N, or corresponding virtual clusters of 1N, with dominant initiator clusters, and nonrandom cluster activation sequences. The occurrence of nonrandom series of identical activation sequences in 4N revealed processes possibly ascribable to neuroplasticity. Hence, our multi-network dissociated cortical assemblies suggest the relevance of pacemaker neurons as essential elements for generating brain network electrophysiological patterns; indeed, such evidence should be considered in the development of computational models for envisaging network behavior both in physiological and pathological conditions.
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Affiliation(s)
- Martina Brofiga
- Department of Informatics, Bioengineering, Robotics, Systems Engineering (DIBRIS), University of Genova, Genova, Italy
- ScreenNeuroPharm, Sanremo, Italy
| | - Serena Losacco
- Department of Pharmacy (DIFAR), University of Genova, Genova, Italy
| | - Fabio Poggio
- Department of Informatics, Bioengineering, Robotics, Systems Engineering (DIBRIS), University of Genova, Genova, Italy
| | - Roberta Arianna Zerbo
- Department of Pharmacy (DIFAR), Pharmacology and Toxicology Unit, University of Genova, Genova, Italy
| | - Marco Milanese
- Department of Pharmacy (DIFAR), Pharmacology and Toxicology Unit, University of Genova, Genova, Italy
- IRCCS Ospedale Policlinico San Martino, Largo Rosanna Benzi 10, 16132, Genova, Italy
| | - Paolo Massobrio
- Department of Informatics, Bioengineering, Robotics, Systems Engineering (DIBRIS), University of Genova, Genova, Italy.
- National Institute for Nuclear Physics (INFN), Genova, Italy.
| | - Bruno Burlando
- Department of Pharmacy (DIFAR), University of Genova, Genova, Italy
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8
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Zheng H, Peri L, Ward GK, Sanders KM, Ward SM. Cardiac PDGFRα + interstitial cells generate spontaneous inward currents that contribute to excitability in the heart. FASEB J 2023; 37:e22929. [PMID: 37086093 PMCID: PMC10402933 DOI: 10.1096/fj.202201712r] [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: 10/20/2022] [Revised: 03/06/2023] [Accepted: 04/05/2023] [Indexed: 04/23/2023]
Abstract
The cell types and conductance that contribute to normal cardiac functions remain under investigation. We used mice that express an enhanced green fluorescent protein (eGFP)-histone 2B fusion protein driven off the cell-specific endogenous promoter for Pdgfra to investigate the distribution and functional role of PDGFRα+ cells in the heart. Cardiac PDGFRα+ cells were widely distributed within the endomysium of atria, ventricle, and sino-atrial node (SAN) tissues. PDGFRα+ cells formed a discrete network of cells, lying in close apposition to neighboring cardiac myocytes in mouse and Cynomolgus monkey (Macaca fascicularis) hearts. Expression of eGFP in nuclei allowed unequivocal identification of these cells following enzymatic dispersion of muscle tissues. FACS purification of PDGFRα+ cells from the SAN and analysis of gene transcripts by qPCR revealed that they were a distinct population of cells that expressed gap junction transcripts, Gja1 and Gjc1. Cardiac PDGFRα+ cells generated spontaneous transient inward currents (STICs) and spontaneous transient depolarizations (STDs) that reversed at 0 mV. Reversal potential was maintained when ECl = -40 mV. [Na+ ]o replacement and FTY720 abolished STICs, suggesting they were due to a non-selective cation conductance (NSCC) carried by TRPM7. PDGFRα+ cells also express β2 -adrenoceptor gene transcripts, Adrb2. Zinterol, a selective β2 -receptor agonist, increased the amplitude and frequency of STICs, suggesting these cells could contribute to adrenergic regulation of cardiac excitability. PDGFRα+ cells in cardiac muscles generate inward currents via an NSCC. STICs generated by these cells may contribute to the integrated membrane potentials of cardiac muscles, possibly affecting the frequency of pacemaker activity.
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Affiliation(s)
- Haifeng Zheng
- Department of Physiology & Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV, 89557, USA
| | - Lauren Peri
- Department of Physiology & Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV, 89557, USA
| | - Grace K. Ward
- Department of Physiology & Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV, 89557, USA
| | - Kenton M. Sanders
- Department of Physiology & Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV, 89557, USA
| | - Sean M. Ward
- Department of Physiology & Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV, 89557, USA
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9
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Ock S, Choi SW, Choi SH, Kang H, Kim SJ, Lee WS, Kim J. Insulin signaling is critical for sinoatrial node maintenance and function. Exp Mol Med 2023; 55:965-973. [PMID: 37121973 PMCID: PMC10238478 DOI: 10.1038/s12276-023-00988-0] [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: 12/17/2022] [Revised: 02/12/2023] [Accepted: 02/12/2023] [Indexed: 05/02/2023] Open
Abstract
Insulin and insulin-like growth factor 1 (IGF-1) signaling regulate cellular growth and glucose metabolism in the myocardium. However, their physiological role in the cells of the cardiac conduction system has never been explored. Therefore, we sought to determine the spatiotemporal function of insulin/IGF-1 receptors in the sinoatrial node (SAN). We generated cardiac conduction cell-specific inducible IGF-1 receptor (IGF-1R) knockout (KO) (CSIGF1RKO), insulin receptor (IR) KO (CSIRKO), and IR/IGF-1R double-KO (CSDIRKO) mice and evaluated their phenotypes. Telemetric electrocardiography revealed regular sinus rhythm in CSIGF1RKO mice, indicating that IGF-1R is dispensable for normal pacemaking. In contrast, CSIRKO and CSDIRKO mice exhibited profound sinus bradycardia. CSDIRKO mice showed typical sinus node dysfunction characterized by junctional rhythm and sinus pauses on electrocardiography. Interestingly, the lack of an insulin receptor in the SAN cells of CSIRKO and CSDIRKO mice caused sinus nodal fibrosis. Mechanistically, hyperpolarization-activated cyclic nucleotide-gated channel 4 (HCN4) protein expression significantly decreased in the CSIRKO and CSDIRKO mice relative to the controls. A patch-clamp study of the SAN cells of CSIRKO mice revealed a significant decrease in the funny current, which is responsible for spontaneous diastolic depolarization in the SAN. This result suggested that insulin receptor loss reduces the heart rate via downregulation of the HCN4 channel. Additionally, HCN1 expression was decreased in CSDIRKO mice, explaining their sinus node dysfunction. Our results reveal a previously unrecognized role of insulin/IGF-1 signaling in sinus node structural maintenance and pacemaker function.
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Affiliation(s)
- Sangmi Ock
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Chung-Ang University, Seoul, Korea
| | - Seong Woo Choi
- Departments of Physiology and Biomedical Sciences, College of Medicine, Seoul National University, Seoul, Korea
- Department of Physiology, Dongguk University College of Medicine, Gyeongju, Korea
| | - Seung Hee Choi
- Division of Endocrinology and Metabolism, Departments of Internal Medicine and Biochemistry and Cell Biology, Kyungpook National University School of Medicine, Daegu, Korea
| | - Hyun Kang
- Department of Anesthesiology, College of Medicine, Chung-Ang University, Seoul, Korea
| | - Sung Joon Kim
- Departments of Physiology and Biomedical Sciences, College of Medicine, Seoul National University, Seoul, Korea
| | - Wang-Soo Lee
- Division of Cardiology, Department of Internal Medicine, College of Medicine, Chung-Ang University, Seoul, Korea.
| | - Jaetaek Kim
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Chung-Ang University, Seoul, Korea.
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10
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Choquet C, Sicard P, Vahdat J, Nguyen THM, Kober F, Varlet I, Bernard M, Richard S, Kelly RG, Lalevée N, Miquerol L. Nkx2-5 Loss of Function in the His-Purkinje System Hampers Its Maturation and Leads to Mechanical Dysfunction. J Cardiovasc Dev Dis 2023; 10:jcdd10050194. [PMID: 37233161 DOI: 10.3390/jcdd10050194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 04/24/2023] [Accepted: 04/25/2023] [Indexed: 05/27/2023] Open
Abstract
The ventricular conduction or His-Purkinje system (VCS) mediates the rapid propagation and precise delivery of electrical activity essential for the synchronization of heartbeats. Mutations in the transcription factor Nkx2-5 have been implicated in a high prevalence of developing ventricular conduction defects or arrhythmias with age. Nkx2-5 heterozygous mutant mice reproduce human phenotypes associated with a hypoplastic His-Purkinje system resulting from defective patterning of the Purkinje fiber network during development. Here, we investigated the role of Nkx2-5 in the mature VCS and the consequences of its loss on cardiac function. Neonatal deletion of Nkx2-5 in the VCS using a Cx40-CreERT2 mouse line provoked apical hypoplasia and maturation defects of the Purkinje fiber network. Genetic tracing analysis demonstrated that neonatal Cx40-positive cells fail to maintain a conductive phenotype after Nkx2-5 deletion. Moreover, we observed a progressive loss of expression of fast-conduction markers in persistent Purkinje fibers. Consequently, Nkx2-5-deleted mice developed conduction defects with progressively reduced QRS amplitude and RSR' complex associated with higher duration. Cardiac function recorded by MRI revealed a reduction in the ejection fraction in the absence of morphological changes. With age, these mice develop a ventricular diastolic dysfunction associated with dyssynchrony and wall-motion abnormalities without indication of fibrosis. These results highlight the requirement of postnatal expression of Nkx2-5 in the maturation and maintenance of a functional Purkinje fiber network to preserve contraction synchrony and cardiac function.
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Affiliation(s)
- Caroline Choquet
- CNRS, IBDM, UMR7288, Aix-Marseille Université, 13009 Marseille, France
- INSERM, MMG, Aix-Marseille Université, 13385 Marseille, France
| | - Pierre Sicard
- INSERM, CNRS, PHYMEDEXP, University de Montpellier, 34295 Montpellier, France
| | - Juliette Vahdat
- CNRS, IBDM, UMR7288, Aix-Marseille Université, 13009 Marseille, France
| | - Thi Hong Minh Nguyen
- CNRS, IBDM, UMR7288, Aix-Marseille Université, 13009 Marseille, France
- INSERM, TAGC, UMR1090, Aix-Marseille Université, 13288 Marseille, France
- Department of Life Sciences, University of Science and Technology of Hanoi, Vietnam Academy of Science and Technology, Hanoi 10072, Vietnam
| | - Frank Kober
- CNRS, CRMBM, Aix-Marseille Université, 13385 Marseille, France
| | - Isabelle Varlet
- CNRS, CRMBM, Aix-Marseille Université, 13385 Marseille, France
| | - Monique Bernard
- CNRS, CRMBM, Aix-Marseille Université, 13385 Marseille, France
| | - Sylvain Richard
- INSERM, CNRS, PHYMEDEXP, University de Montpellier, 34295 Montpellier, France
| | - Robert G Kelly
- CNRS, IBDM, UMR7288, Aix-Marseille Université, 13009 Marseille, France
| | - Nathalie Lalevée
- INSERM, TAGC, UMR1090, Aix-Marseille Université, 13288 Marseille, France
- INSERM, C2VN, UMR1263, Aix-Marseille Université, 13005 Marseille, France
| | - Lucile Miquerol
- CNRS, IBDM, UMR7288, Aix-Marseille Université, 13009 Marseille, France
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11
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Sun D, Wang Q. The application of SUDEP in forensic diagnosis: a mini review. Front Neurol 2023; 14:1169003. [PMID: 37181558 PMCID: PMC10169668 DOI: 10.3389/fneur.2023.1169003] [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: 02/18/2023] [Accepted: 03/20/2023] [Indexed: 05/16/2023] Open
Abstract
In the epilepsy population, the risk of sudden death from epilepsy is rare but is ~24 times greater than the risk of sudden death from other causes. Sudden unexpected death in epilepsy (SUDEP) has been widely recognized in clinical studies. Despite its significance as a cause of death, SUDEP is rarely used in forensic practice. This review focuses on the forensic characteristics of SUDEP, analyzed the reasons for its underuse in forensic practice, and illustrated the prospect of establishing uniform diagnostic criteria for sudden unexpected death in epilepsy and molecular anatomy in aiding forensic diagnosis.
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Affiliation(s)
| | - Qiang Wang
- Forensic Science Center, East China University of Political Science and Law, Shanghai, China
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12
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Hatthakone T, Oundavong S, Soejima Y, Sawabe M. Development of a new histological identification method of human sinoatrial node suitable for immunohistochemical study. Anat Sci Int 2023; 98:293-305. [PMID: 36422826 DOI: 10.1007/s12565-022-00697-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 11/07/2022] [Indexed: 11/27/2022]
Abstract
Histological identification of the human sinoatrial node (SAN) remains a challenge. Conventional identification methods, such as Lev's method, have certain limitations. The aim of our study was to develop a new histological identification method that could properly identify the sinoatrial node, applicable to the immunohistochemical study of intra-nodal structures. Thirty-nine human autopsied hearts were included in this study. The cases included 23 men and 16 women ranging in age from 20 to 99 years. The sinoatrial area from eight control samples was cut in the vertical section using the conventional Lev's method. In our new method, called the "En face one-block method," the sinoatrial node was cut in "En face" at the junction of the right border of the right appendage and superior vena cava, placed in one long cassette, and serially cut using a microtome. Immunostaining was performed using primary antibodies against CD31, podoplanin (D2-40), S-100, and other proteins. The average area of the SAN on the slide glass in our new method was 32.2 mm2, which was significantly larger than that (3.59 mm2) of the control samples by Lev's method. The SAN area was positively correlated with age (r = 0.357; p = 0.026), especially in women (r = 0.626; p = 0.0095). The SAN group had significantly lower percentage of CD31-positive blood capillaries, higher percentage of podoplanin-positive lymphatic channels, and S-100-positive peripheral nerves. We successfully developed a novel cutting method applicable to immunohistochemical studies, with which we could provide a bird's-eye view of the sinoatrial nodes.
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Affiliation(s)
- Thavisouk Hatthakone
- Department of Molecular Pathology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo, 113-8510, Japan
| | - Sunti Oundavong
- Department of Molecular Pathology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo, 113-8510, Japan
| | - Yurie Soejima
- Department of Molecular Pathology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo, 113-8510, Japan
| | - Motoji Sawabe
- Department of Molecular Pathology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo, 113-8510, Japan.
- Department of Molecular Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo, 113-8519, Japan.
- Department of Diagnostic Pathology, Hitachi General Hospital, 2-1-1 Jonancho, Hitachi, Ibaraki, 317-0077, Japan.
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13
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Frequency-Dependent Properties of the Hyperpolarization-Activated Cation Current, I f, in Adult Mouse Heart Primary Pacemaker Myocytes. Int J Mol Sci 2022; 23:ijms23084299. [PMID: 35457119 PMCID: PMC9024942 DOI: 10.3390/ijms23084299] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 04/05/2022] [Accepted: 04/11/2022] [Indexed: 02/04/2023] Open
Abstract
A number of distinct electrophysiological mechanisms that modulate the myogenic spontaneous pacemaker activity in the sinoatrial node (SAN) of the mammalian heart have been investigated extensively. There is agreement that several (3 or 4) different transmembrane ionic current changes (referred to as the voltage clock) are involved; and that the resulting net current interacts with direct and indirect effects of changes in intracellular Ca2+ (the calcium clock). However, significant uncertainties, and important knowledge gaps, remain concerning the functional roles in SAN spontaneous pacing of many of the individual ion channel- or exchanger-mediated transmembrane current changes. We report results from patch clamp studies and mathematical modeling of the hyperpolarization-activated current, If, in the generation/modulation of the diastolic depolarization, or pacemaker potential, produced by individual myocytes that were enzymatically isolated from the adult mouse sinoatrial node (SAN). Amphotericin-mediated patch microelectrode recordings at 35 °C were made under control conditions and in the presence of 5 or 10 nM isoproterenol (ISO). These sets of results were complemented and integrated with mathematical modeling of the current changes that take place in the range of membrane potentials (−70 to −50 mV), which corresponds to the ‘pacemaker depolarization’ in the adult mouse SAN. Our results reveal a very small, but functionally important, approximately steady-state or time-independent current generated by residual activation of If channels that are expressed in these pacemaker myocytes. Recordings of the pacemaker depolarization and action potential, combined with measurements of changes in If, and the well-known increases in the L-type Ca2+ current, ICaL, demonstrated that ICaL activation, is essential for myogenic pacing. Moreover, after being enhanced (approximately 3-fold) by 5 or 10 nM ISO, ICaL contributes significantly to the positive chronotropic effect. Our mathematical model has been developed in an attempt to better understand the underlying mechanisms for the pacemaker depolarization and action potential in adult mouse SAN myocytes. After being updated with our new experimental data describing If, our simulations reveal a novel functional component of If in adult mouse SAN. Computational work carried out with this model also confirms that in the presence of ISO the residual activation of If and opening of ICaL channels combine to generate a net current change during the slow diastolic depolarization phase that is essential for the observed accelerated pacemaking rate of these SAN myocytes.
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14
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Louradour J, Bortolotti O, Torre E, Bidaud I, Lamb N, Fernandez A, Le Guennec JY, Mangoni ME, Mesirca P. L-Type Cav1.3 Calcium Channels Are Required for Beta-Adrenergic Triggered Automaticity in Dormant Mouse Sinoatrial Pacemaker Cells. Cells 2022; 11:cells11071114. [PMID: 35406677 PMCID: PMC8997967 DOI: 10.3390/cells11071114] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 03/18/2022] [Accepted: 03/23/2022] [Indexed: 11/16/2022] Open
Abstract
Background: Sinoatrial node cells (SANC) automaticity is generated by functional association between the activity of plasmalemmal ion channels and local diastolic intracellular Ca2+ release (LCR) from ryanodine receptors. Strikingly, most isolated SANC exhibit a “dormant” state, whereas only a fraction shows regular firing as observed in intact SAN. Recent studies showed that β-adrenergic stimulation can initiate spontaneous firing in dormant SANC, though this mechanism is not entirely understood. Methods: To investigate the role of L-type Cav1.3 Ca2+ channels in the adrenergic regulation of automaticity in dormant SANC, we used a knock-in mouse strain in which the sensitivity of L-type Cav1.2 α1 subunits to dihydropyridines (DHPs) was inactivated (Cav1.2DHP−/−), enabling the selective pharmacological inhibition of Cav1.3 by DHPs. Results: In dormant SANC, β-adrenergic stimulation with isoproterenol (ISO) induced spontaneous action potentials (AP) and Ca2+ transients, which were completely arrested with concomitant perfusion of the DHP nifedipine. In spontaneously firing SANC at baseline, Cav1.3 inhibition completely reversed the effect of β-adrenergic stimulation on AP and the frequency of Ca2+ transients. Confocal calcium imaging of SANC showed that the β-adrenergic-induced synchronization of LCRs is regulated by the activity of Cav1.3 channels. Conclusions: Our study shows a novel role of Cav1.3 channels in initiating and maintaining automaticity in dormant SANC upon β-adrenergic stimulation.
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Affiliation(s)
- Julien Louradour
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34090 Montpellier, France; (J.L.); (O.B.); (E.T.); (I.B.)
- LabEx Ion Channels Science and Therapeutics (ICST), 34090 Montpellier, France
- PhyMedExp, Université de Montpellier, INSERM U1046, UMR CNRS, 34090 Montpellier, France;
| | - Olivier Bortolotti
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34090 Montpellier, France; (J.L.); (O.B.); (E.T.); (I.B.)
- LabEx Ion Channels Science and Therapeutics (ICST), 34090 Montpellier, France
| | - Eleonora Torre
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34090 Montpellier, France; (J.L.); (O.B.); (E.T.); (I.B.)
- LabEx Ion Channels Science and Therapeutics (ICST), 34090 Montpellier, France
| | - Isabelle Bidaud
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34090 Montpellier, France; (J.L.); (O.B.); (E.T.); (I.B.)
- LabEx Ion Channels Science and Therapeutics (ICST), 34090 Montpellier, France
| | - Ned Lamb
- Mammalian Stem Cell Biology Group, Institute of Human Genetics, Université de Montpellier, CNRS, 34090 Montpellier, France; (N.L.); (A.F.)
| | - Anne Fernandez
- Mammalian Stem Cell Biology Group, Institute of Human Genetics, Université de Montpellier, CNRS, 34090 Montpellier, France; (N.L.); (A.F.)
| | - Jean-Yves Le Guennec
- PhyMedExp, Université de Montpellier, INSERM U1046, UMR CNRS, 34090 Montpellier, France;
| | - Matteo E. Mangoni
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34090 Montpellier, France; (J.L.); (O.B.); (E.T.); (I.B.)
- LabEx Ion Channels Science and Therapeutics (ICST), 34090 Montpellier, France
- Correspondence: (M.E.M.); (P.M.)
| | - Pietro Mesirca
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, 34090 Montpellier, France; (J.L.); (O.B.); (E.T.); (I.B.)
- LabEx Ion Channels Science and Therapeutics (ICST), 34090 Montpellier, France
- Correspondence: (M.E.M.); (P.M.)
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15
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Calcium Channels in the Heart: Disease States and Drugs. Cells 2022; 11:cells11060943. [PMID: 35326393 PMCID: PMC8945986 DOI: 10.3390/cells11060943] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 02/28/2022] [Accepted: 03/04/2022] [Indexed: 12/30/2022] Open
Abstract
Calcium ions are the major signaling ions in the cells. They regulate muscle contraction, neurotransmitter secretion, cell growth and migration, and the activity of several proteins including enzymes and ion channels and transporters. They participate in various signal transduction pathways, thereby regulating major physiological functions. Calcium ion entry into the cells is regulated by specific calcium channels and transporters. There are mainly six types of calcium channels, of which only two are prominent in the heart. In cardiac tissues, the two types of calcium channels are the L type and the T type. L-type channels are found in all cardiac cells and T-type are expressed in Purkinje cells, pacemaker and atrial cells. Both these types of channels contribute to atrioventricular conduction as well as pacemaker activity. Given the crucial role of calcium channels in the cardiac conduction system, mutations and dysfunctions of these channels are known to cause several diseases and disorders. Drugs targeting calcium channels hence are used in a wide variety of cardiac disorders including but not limited to hypertension, angina, and arrhythmias. This review summarizes the type of cardiac calcium channels, their function, and disorders caused by their mutations and dysfunctions. Finally, this review also focuses on the types of calcium channel blockers and their use in a variety of cardiac disorders.
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16
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Chloe Li KY, Cook AC, Lovering RC. GOing Forward With the Cardiac Conduction System Using Gene Ontology. Front Genet 2022; 13:802393. [PMID: 35309148 PMCID: PMC8924464 DOI: 10.3389/fgene.2022.802393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 02/09/2022] [Indexed: 02/03/2023] Open
Abstract
The cardiac conduction system (CCS) comprises critical components responsible for the initiation, propagation, and coordination of the action potential. Aberrant CCS development can cause conduction abnormalities, including sick sinus syndrome, accessory pathways, and atrioventricular and bundle branch blocks. Gene Ontology (GO; http://geneontology.org/) is an invaluable global bioinformatics resource which provides structured, computable knowledge describing the functions of gene products. Many gene products are known to be involved in CCS development; however, this information is not comprehensively captured by GO. To address the needs of the heart development research community, this study aimed to describe the specific roles of proteins reported in the literature to be involved with CCS development and/or function. 14 proteins were prioritized for GO annotation which led to the curation of 15 peer-reviewed primary experimental articles using carefully selected GO terms. 152 descriptive GO annotations, including those describing sinoatrial node and atrioventricular node development were created and submitted to the GO Consortium database. A functional enrichment analysis of 35 key CCS development proteins confirmed that this work has improved the in-silico interpretation of this CCS dataset. This work may improve future investigations of the CCS with application of high-throughput methods such as genome-wide association studies analysis, proteomics, and transcriptomics.
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Affiliation(s)
- Kan Yan Chloe Li
- Department of Preclinical and Fundamental Science, Institute of Cardiovascular Science, Functional Gene Annotation, University College London, London, United Kingdom,Department of Children’s Cardiovascular Disease, Centre for Morphology and Structural Heart Disease, Institute of Cardiovascular Science, University College London, London, United Kingdom,*Correspondence: Kan Yan Chloe Li,
| | - Andrew C Cook
- Department of Children’s Cardiovascular Disease, Centre for Morphology and Structural Heart Disease, Institute of Cardiovascular Science, University College London, London, United Kingdom
| | - Ruth C Lovering
- Department of Preclinical and Fundamental Science, Institute of Cardiovascular Science, Functional Gene Annotation, University College London, London, United Kingdom
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17
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Al Kury LT, Chacar S, Alefishat E, Khraibi AA, Nader M. Structural and Electrical Remodeling of the Sinoatrial Node in Diabetes: New Dimensions and Perspectives. Front Endocrinol (Lausanne) 2022; 13:946313. [PMID: 35872997 PMCID: PMC9302195 DOI: 10.3389/fendo.2022.946313] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 06/14/2022] [Indexed: 11/14/2022] Open
Abstract
The sinoatrial node (SAN) is composed of highly specialized cells that mandate the spontaneous beating of the heart through self-generation of an action potential (AP). Despite this automaticity, the SAN is under the modulation of the autonomic nervous system (ANS). In diabetes mellitus (DM), heart rate variability (HRV) manifests as a hallmark of diabetic cardiomyopathy. This is paralleled by an impaired regulation of the ANS, and by a pathological remodeling of the pacemaker structure and function. The direct effect of diabetes on the molecular signatures underscoring this pathology remains ill-defined. The recent focus on the electrical currents of the SAN in diabetes revealed a repressed firing rate of the AP and an elongation of its tracing, along with conduction abnormalities and contractile failure. These changes are blamed on the decreased expression of ion transporters and cell-cell communication ports at the SAN (i.e., HCN4, calcium and potassium channels, connexins 40, 45, and 46) which further promotes arrhythmias. Molecular analysis crystallized the RGS4 (regulator of potassium currents), mitochondrial thioredoxin-2 (reactive oxygen species; ROS scavenger), and the calcium-dependent calmodulin kinase II (CaMKII) as metabolic culprits of relaying the pathological remodeling of the SAN cells (SANCs) structure and function. A special attention is given to the oxidation of CaMKII and the generation of ROS that induce cell damage and apoptosis of diabetic SANCs. Consequently, the diabetic SAN contains a reduced number of cells with significant infiltration of fibrotic tissues that further delay the conduction of the AP between the SANCs. Failure of a genuine generation of AP and conduction of their derivative waves to the neighboring atrial myocardium may also occur as a result of the anti-diabetic regiment (both acute and/or chronic treatments). All together, these changes pose a challenge in the field of cardiology and call for further investigations to understand the etiology of the structural/functional remodeling of the SANCs in diabetes. Such an understanding may lead to more adequate therapies that can optimize glycemic control and improve health-related outcomes in patients with diabetes.
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Affiliation(s)
- Lina T. Al Kury
- Department of Health Sciences, College of Natural and Health Sciences, Zayed University, Abu Dhabi, United Arab Emirates
- *Correspondence: Lina T. Al Kury, ; Moni Nader,
| | - Stephanie Chacar
- Department of Physiology and Immunology, College of Medicine and Health Sciences, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
| | - Eman Alefishat
- Department of Pharmacology, College of Medicine and Health Sciences, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
- Department of Biopharmaceutics and Clinical Pharmacy, School of Pharmacy, The University of Jordan, Amman, Jordan
- Center for Biotechnology, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
| | - Ali A. Khraibi
- Department of Physiology and Immunology, College of Medicine and Health Sciences, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
- Center for Biotechnology, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
| | - Moni Nader
- Department of Physiology and Immunology, College of Medicine and Health Sciences, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
- Center for Biotechnology, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
- *Correspondence: Lina T. Al Kury, ; Moni Nader,
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18
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Dixon RE, Navedo MF, Binder MD, Santana LF. Mechanisms and Physiological Implications of Cooperative Gating of Ion Channels Clusters. Physiol Rev 2021; 102:1159-1210. [PMID: 34927454 DOI: 10.1152/physrev.00022.2021] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Ion channels play a central role in the regulation of nearly every cellular process. Dating back to the classic 1952 Hodgkin-Huxley model of the generation of the action potential, ion channels have always been thought of as independent agents. A myriad of recent experimental findings exploiting advances in electrophysiology, structural biology, and imaging techniques, however, have posed a serious challenge to this long-held axiom as several classes of ion channels appear to open and close in a coordinated, cooperative manner. Ion channel cooperativity ranges from variable-sized oligomeric cooperative gating in voltage-gated, dihydropyridine-sensitive Cav1.2 and Cav1.3 channels to obligatory dimeric assembly and gating of voltage-gated Nav1.5 channels. Potassium channels, transient receptor potential channels, hyperpolarization cyclic nucleotide-activated channels, ryanodine receptors (RyRs), and inositol trisphosphate receptors (IP3Rs) have also been shown to gate cooperatively. The implications of cooperative gating of these ion channels range from fine tuning excitation-contraction coupling in muscle cells to regulating cardiac function and vascular tone, to modulation of action potential and conduction velocity in neurons and cardiac cells, and to control of pace-making activity in the heart. In this review, we discuss the mechanisms leading to cooperative gating of ion channels, their physiological consequences and how alterations in cooperative gating of ion channels may induce a range of clinically significant pathologies.
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Affiliation(s)
- Rose Ellen Dixon
- Department of Physiology and Membrane Biology, University of California, Davis, CA, United States
| | - Manuel F Navedo
- Department of Pharmacology, University of California, Davis, CA, United States
| | - Marc D Binder
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, United States
| | - L Fernando Santana
- Department of Physiology and Membrane Biology, University of California, Davis, CA, United States
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19
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Turner D, Kang C, Mesirca P, Hong J, Mangoni ME, Glukhov AV, Sah R. Electrophysiological and Molecular Mechanisms of Sinoatrial Node Mechanosensitivity. Front Cardiovasc Med 2021; 8:662410. [PMID: 34434970 PMCID: PMC8382116 DOI: 10.3389/fcvm.2021.662410] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 06/24/2021] [Indexed: 01/01/2023] Open
Abstract
The understanding of the electrophysiological mechanisms that underlie mechanosensitivity of the sinoatrial node (SAN), the primary pacemaker of the heart, has been evolving over the past century. The heart is constantly exposed to a dynamic mechanical environment; as such, the SAN has numerous canonical and emerging mechanosensitive ion channels and signaling pathways that govern its ability to respond to both fast (within second or on beat-to-beat manner) and slow (minutes) timescales. This review summarizes the effects of mechanical loading on the SAN activity and reviews putative candidates, including fast mechanoactivated channels (Piezo, TREK, and BK) and slow mechanoresponsive ion channels [including volume-regulated chloride channels and transient receptor potential (TRP)], as well as the components of mechanochemical signal transduction, which may contribute to SAN mechanosensitivity. Furthermore, we examine the structural foundation for both mechano-electrical and mechanochemical signal transduction and discuss the role of specialized membrane nanodomains, namely, caveolae, in mechanical regulation of both membrane and calcium clock components of the so-called coupled-clock pacemaker system responsible for SAN automaticity. Finally, we emphasize how these mechanically activated changes contribute to the pathophysiology of SAN dysfunction and discuss controversial areas necessitating future investigations. Though the exact mechanisms of SAN mechanosensitivity are currently unknown, identification of such components, their impact into SAN pacemaking, and pathological remodeling may provide new therapeutic targets for the treatment of SAN dysfunction and associated rhythm abnormalities.
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Affiliation(s)
- Daniel Turner
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, United States
| | - Chen Kang
- Cardiovascular Division, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO, United States
| | - Pietro Mesirca
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Juan Hong
- Cardiovascular Division, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO, United States
| | - Matteo E Mangoni
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Alexey V Glukhov
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, United States
| | - Rajan Sah
- Cardiovascular Division, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO, United States
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20
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Al Sayed ZR, Canac R, Cimarosti B, Bonnard C, Gourraud JB, Hamamy H, Kayserili H, Girardeau A, Jouni M, Jacob N, Gaignerie A, Chariau C, David L, Forest V, Marionneau C, Charpentier F, Loussouarn G, Lamirault G, Reversade B, Zibara K, Lemarchand P, Gaborit N. Human model of IRX5 mutations reveals key role for this transcription factor in ventricular conduction. Cardiovasc Res 2021; 117:2092-2107. [PMID: 32898233 DOI: 10.1093/cvr/cvaa259] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 01/15/2020] [Accepted: 08/28/2020] [Indexed: 01/02/2023] Open
Abstract
AIMS Several inherited arrhythmic diseases have been linked to single gene mutations in cardiac ion channels and interacting proteins. However, the mechanisms underlying most arrhythmias, are thought to involve altered regulation of the expression of multiple effectors. In this study, we aimed to examine the role of a transcription factor (TF) belonging to the Iroquois homeobox family, IRX5, in cardiac electrical function. METHODS AND RESULTS Using human cardiac tissues, transcriptomic correlative analyses between IRX5 and genes involved in cardiac electrical activity showed that in human ventricular compartment, IRX5 expression strongly correlated to the expression of major actors of cardiac conduction, including the sodium channel, Nav1.5, and Connexin 40 (Cx40). We then generated human-induced pluripotent stem cells (hiPSCs) derived from two Hamamy syndrome-affected patients carrying distinct homozygous loss-of-function mutations in IRX5 gene. Cardiomyocytes derived from these hiPSCs showed impaired cardiac gene expression programme, including misregulation in the control of Nav1.5 and Cx40 expression. In accordance with the prolonged QRS interval observed in Hamamy syndrome patients, a slower ventricular action potential depolarization due to sodium current reduction was observed on electrophysiological analyses performed on patient-derived cardiomyocytes, confirming the functional role of IRX5 in electrical conduction. Finally, a cardiac TF complex was newly identified, composed by IRX5 and GATA4, in which IRX5 potentiated GATA4-induction of SCN5A expression. CONCLUSION Altogether, this work unveils a key role for IRX5 in the regulation of human ventricular depolarization and cardiac electrical conduction, providing therefore new insights into our understanding of cardiac diseases.
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Affiliation(s)
- Zeina R Al Sayed
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
| | - Robin Canac
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
| | - Bastien Cimarosti
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
| | - Carine Bonnard
- Institute of Medical Biology, A*STAR, 8A Biomedical Grove, Singapore 138648, Singapore
| | - Jean-Baptiste Gourraud
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
- Université de Nantes, CHU Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
| | - Hanan Hamamy
- Department of Genetic Medicine and Development, Geneva University, 1 rue Michel-Servet, Geneva 1211, Switzerland
| | - Hulya Kayserili
- Medical Genetics Department, Koç University School of Medicine(KUSOM), Rumelifeneri Yolu 34450, Istanbul, Turkey
| | - Aurore Girardeau
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
| | - Mariam Jouni
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
| | - Nicolas Jacob
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
| | - Anne Gaignerie
- Université de Nantes, CHU Nantes, Inserm, CNRS, SFR Santé, Inserm UMS 016, CNRS UMS 3556, 8 Quai Moncousu, F-44000 Nantes, France
| | - Caroline Chariau
- Université de Nantes, CHU Nantes, Inserm, CNRS, SFR Santé, Inserm UMS 016, CNRS UMS 3556, 8 Quai Moncousu, F-44000 Nantes, France
| | - Laurent David
- Université de Nantes, CHU Nantes, Inserm, CNRS, SFR Santé, Inserm UMS 016, CNRS UMS 3556, 8 Quai Moncousu, F-44000 Nantes, France
- Université de Nantes, INSERM, CRTI, 30 Bd Jean Monnet, F-44093 Nantes, France
- ITUN, CHU Nantes, 30 Bd Jean Monnet, F-44093 Nantes, France
| | - Virginie Forest
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
| | - Céline Marionneau
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
| | - Flavien Charpentier
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
- Université de Nantes, CHU Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
| | - Gildas Loussouarn
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
| | - Guillaume Lamirault
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
- Université de Nantes, CHU Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
| | - Bruno Reversade
- Institute of Medical Biology, A*STAR, 8A Biomedical Grove, Singapore 138648, Singapore
- Medical Genetics Department, Koç University School of Medicine(KUSOM), Rumelifeneri Yolu 34450, Istanbul, Turkey
- Department of Paediatrics, National University of Singapore, 1E Kent Ridge Road, Singapore 119228, Singapore
- Institute of Molecular and Cellular Biology, A*STAR, 61 Biopolis Drive, Singapore 138673, Singapore
- Reproductive Biology Laboratory, Amsterdam UMC, Meibergdreef 9 1105, Amsterdam-Zuidoost, Netherlands
| | - Kazem Zibara
- ER045, Laboratory of stem cells, DSST, Biology department, Faculty of Sciences, Lebanese University, Rafic Hariri Campus - Hadath, Beirut 1700, Lebanon
| | - Patricia Lemarchand
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
- Université de Nantes, CHU Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
| | - Nathalie Gaborit
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 8 quai Moncousu, F-44000 Nantes, France
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21
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Mantri S, Wu SM, Goodyer WR. Molecular Profiling of the Cardiac Conduction System: the Dawn of a New Era. Curr Cardiol Rep 2021; 23:103. [PMID: 34196831 DOI: 10.1007/s11886-021-01536-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/17/2021] [Indexed: 11/28/2022]
Abstract
PURPOSE OF REVIEW Recent technological advances have led to an increased ability to define the gene expression profile of the cardiac conduction system (CCS). Here, we review the most salient studies to emerge in recent years and discuss existing gaps in our knowledge as well as future areas of investigation. RECENT FINDINGS Molecular profiling of the CCS spans several decades. However, the advent of high-throughput sequencing strategies has allowed for the discovery of unique transcriptional programs of the many diverse CCS cell types. The CCS, a diverse structure with significant inter- and intra-component cellular heterogeneity, is essential to the normal function of the heart. Progress in transcriptomic profiling has improved the resolution and depth of characterization of these unique and clinically relevant CCS cell types. Future studies leveraging this big data will play a crucial role in improving our understanding of CCS development and function as well as translating these findings into tangible translational tools for the improved detection, prevention, and treatment of cardiac arrhythmias.
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Affiliation(s)
- Sruthi Mantri
- Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Sean M Wu
- Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, 94305, USA.,Division of Pediatric Cardiology, Department of Pediatrics, Stanford University, Stanford, CA, 94305, USA.,Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - William R Goodyer
- Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, 94305, USA. .,Division of Pediatric Cardiology, Department of Pediatrics, Stanford University, Stanford, CA, 94305, USA. .,Division of Pediatric Cardiology, Electrophysiology, Department of Pediatrics, Lucile Packard Children's Hospital, Stanford University School of Medicine, Room G1105 Lokey Stem Cell Research Building, 265 Campus Drive, Stanford, CA, 94305, USA.
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22
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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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23
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Ronzhina M, Stracina T, Lacinova L, Ondacova K, Pavlovicova M, Marsanova L, Smisek R, Janousek O, Fialova K, Kolarova J, Novakova M, Provaznik I. Di-4-ANEPPS Modulates Electrical Activity and Progress of Myocardial Ischemia in Rabbit Isolated Heart. Front Physiol 2021; 12:667065. [PMID: 34177617 PMCID: PMC8222999 DOI: 10.3389/fphys.2021.667065] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 04/12/2021] [Indexed: 11/16/2022] Open
Abstract
Aims Although voltage-sensitive dye di-4-ANEPPS is a common tool for mapping cardiac electrical activity, reported effects on electrophysiological parameters are rather. The main goals of the study were to reveal effects of the dye on rabbit isolated heart and to verify, whether rabbit isolated heart stained with di-4-ANEPPS is a suitable tool for myocardial ischemia investigation. Methods and Results Study involved experiments on stained (n = 9) and non-stained (n = 11) Langendorff perfused rabbit isolated hearts. Electrophysiological effects of the dye were evaluated by analysis of various electrogram (EG) parameters using common paired and unpaired statistical tests. It was shown that staining the hearts with di-4-ANEPPS leads to only short-term sporadic prolongation of impulse conduction through atria and atrioventricular node. On the other hand, significant irreversible slowing of heart rate and ventricular conduction were found in stained hearts as compared to controls. In patch clamp experiments, significant inhibition of sodium current density was observed in differentiated NG108-15 cells stained by the dye. Although no significant differences in mean number of ventricular premature beats were found between the stained and the non-stained hearts in ischemia as well as in reperfusion, all abovementioned results indicate increased arrhythmogenicity. In isolated hearts during ischemia, prominent ischemic patterns appeared in the stained hearts with 3–4 min delay as compared to the non-stained ones. Moreover, the ischemic changes did not achieve the same magnitude as in controls even after 10 min of ischemia. It resulted in poor performance of ischemia detection by proposed EG parameters, as was quantified by receiver operating characteristics analysis. Conclusion Our results demonstrate significant direct irreversible effect of di-4-ANEPPS on spontaneous heart rate and ventricular impulse conduction in rabbit isolated heart model. Particularly, this should be considered when di-4-ANEPPS is used in ischemia studies in rabbit. Delayed attenuated response of such hearts to ischemia might lead to misinterpretation of obtained results.
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Affiliation(s)
- Marina Ronzhina
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czechia
| | - Tibor Stracina
- Department of Physiology, Faculty of Medicine, Masaryk University, Brno, Czechia
| | - Lubica Lacinova
- Centre of Biosciences, Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Katarina Ondacova
- Centre of Biosciences, Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Michaela Pavlovicova
- Centre of Biosciences, Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Lucie Marsanova
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czechia
| | - Radovan Smisek
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czechia
| | - Oto Janousek
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czechia
| | - Katerina Fialova
- Department of Physiology, Faculty of Medicine, Masaryk University, Brno, Czechia
| | - Jana Kolarova
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czechia
| | - Marie Novakova
- Department of Physiology, Faculty of Medicine, Masaryk University, Brno, Czechia.,International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czechia
| | - Ivo Provaznik
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czechia
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24
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Kiuchi S, Usami A, Shimoyama T, Otsuka F, Suzuki S, Ono K. Generation of cardiomyocytes by atrioventricular node cells in long-term cultures. Biochem Biophys Rep 2021; 26:101018. [PMID: 34095551 PMCID: PMC8166639 DOI: 10.1016/j.bbrep.2021.101018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 05/06/2021] [Accepted: 05/06/2021] [Indexed: 11/08/2022] Open
Abstract
Turnover of cardiac pacemaker cells may occur during the lifetime of the body, and we recently raised the hypothesis that specialized cardiac cells have in common the potential to generate cardiomyocytes from fibroblasts. To examine this hypothesis, we analyzed the ability of atrioventricular node cells (AVNCs) to generate functional cardiomyocytes in long-term culture. AVNCs were isolated from adult guinea pig hearts and cultured for up to three weeks. Under phase-contrast microscopic observation over time, it was found that within a week, a number of fibroblasts gathered around the AVNCs and formed cell clusters, and thereafter the cell clusters started to beat spontaneously. The nascent cell clusters expanded their area gradually by three weeks in culture and expressed specific cardiac genes and proteins. Maturation of newly formed cardiomyocytes seems to be slow in cultures of AVNCs compared with those of sinoatrial node cells. Stimulation of muscarinic receptors with acetylcholine induced a beating rate decrease which was blocked by atropine, and activation of adenylate cyclase activity with forskolin increased the beat rate, while stimulation of beta adrenoceptors by isoproterenol had no effect. These results indicate that AVNCs form a cluster of cells with properties of functional cardiomyocytes and provide evidence to support the hypothesis. Atrioventricular node cells formed spontaneously beating cell clusters in culture. The cell clusters expressed specific cardiac genes and proteins. The properties of the cell clusters depended on their spontaneous beating rate. Specialized cardiac cells may in common have the ability to generate cardiomyocytes.
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Affiliation(s)
- Shigeki Kiuchi
- Laboratory of Molecular Physiology and Pharmacology, Faculty of Pharma-Sciences, Teikyo University, Itabashi-Ku, Tokyo, 173-8605, Japan
| | - Akino Usami
- Laboratory of Molecular Physiology and Pharmacology, Faculty of Pharma-Sciences, Teikyo University, Itabashi-Ku, Tokyo, 173-8605, Japan
| | - Tae Shimoyama
- Laboratory of Molecular Environmental Health, Faculty of Pharma-Sciences, Teikyo University, Itabashi-Ku, Tokyo, 173-8605, Japan
| | - Fuminori Otsuka
- Laboratory of Molecular Environmental Health, Faculty of Pharma-Sciences, Teikyo University, Itabashi-Ku, Tokyo, 173-8605, Japan
| | - Shigeto Suzuki
- Laboratory of Molecular Physiology and Pharmacology, Faculty of Pharma-Sciences, Teikyo University, Itabashi-Ku, Tokyo, 173-8605, Japan
| | - Kageyoshi Ono
- Laboratory of Molecular Physiology and Pharmacology, Faculty of Pharma-Sciences, Teikyo University, Itabashi-Ku, Tokyo, 173-8605, Japan
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25
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Kolesnikova ЕE. Anatomical and Physiological Peculiarities
of the Heart in Jawless and Jawed Fish. J EVOL BIOCHEM PHYS+ 2021. [DOI: 10.1134/s0022093021020022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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26
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Hu W, Clark RB, Giles WR, Shibata E, Zhang H. Physiological Roles of the Rapidly Activated Delayed Rectifier K + Current in Adult Mouse Heart Primary Pacemaker Activity. Int J Mol Sci 2021; 22:4761. [PMID: 33946248 PMCID: PMC8124469 DOI: 10.3390/ijms22094761] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 04/27/2021] [Accepted: 04/28/2021] [Indexed: 01/01/2023] Open
Abstract
Robust, spontaneous pacemaker activity originating in the sinoatrial node (SAN) of the heart is essential for cardiovascular function. Anatomical, electrophysiological, and molecular methods as well as mathematical modeling approaches have quite thoroughly characterized the transmembrane fluxes of Na+, K+ and Ca2+ that produce SAN action potentials (AP) and 'pacemaker depolarizations' in a number of different in vitro adult mammalian heart preparations. Possible ionic mechanisms that are responsible for SAN primary pacemaker activity are described in terms of: (i) a Ca2+-regulated mechanism based on a requirement for phasic release of Ca2+ from intracellular stores and activation of an inward current-mediated by Na+/Ca2+ exchange; (ii) time- and voltage-dependent activation of Na+ or Ca2+ currents, as well as a cyclic nucleotide-activated current, If; and/or (iii) a combination of (i) and (ii). Electrophysiological studies of single spontaneously active SAN myocytes in both adult mouse and rabbit hearts consistently reveal significant expression of a rapidly activating time- and voltage-dependent K+ current, often denoted IKr, that is selectively expressed in the leading or primary pacemaker region of the adult mouse SAN. The main goal of the present study was to examine by combined experimental and simulation approaches the functional or physiological roles of this K+ current in the pacemaker activity. Our patch clamp data of mouse SAN myocytes on the effects of a pharmacological blocker, E4031, revealed that a rapidly activating K+ current is essential for action potential (AP) repolarization, and its deactivation during the pacemaker potential contributes a small but significant component to the pacemaker depolarization. Mathematical simulations using a murine SAN AP model confirm that well known biophysical properties of a delayed rectifier K+ current can contribute to its role in generating spontaneous myogenic activity.
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Affiliation(s)
- Wei Hu
- Biological Physics Group, Department of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, UK;
| | - Robert B. Clark
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada; (R.B.C.); (W.R.G.)
| | - Wayne R. Giles
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada; (R.B.C.); (W.R.G.)
| | - Erwin Shibata
- Department of Physiology, Carver School of Medicine, University of Iowa, Iowa City, IA 52242, USA;
| | - Henggui Zhang
- Biological Physics Group, Department of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, UK;
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou 646000, China
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27
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Hennis K, Biel M, Wahl-Schott C, Fenske S. Beyond pacemaking: HCN channels in sinoatrial node function. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2021; 166:51-60. [PMID: 33753086 DOI: 10.1016/j.pbiomolbio.2021.03.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 03/04/2021] [Accepted: 03/16/2021] [Indexed: 01/16/2023]
Abstract
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are key proteins involved in the initiation and regulation of the heartbeat. Pacemaker cells within the sinoatrial node generate the electrical impulse that underlies the contraction of all atrial and ventricular cardiomyocytes. To generate a stable heart rhythm, it is necessary that the spontaneous activity of pacemaker cells is synchronized. Entrainment processes in the sinoatrial node create synchrony and also mediate heart rate regulation. In the past years it has become clear that the role of HCN channels goes beyond just pacemaking and that the channels play pivotal roles in these entrainment processes that coordinate and balance sinoatrial node network activity. Here, we review the role of HCN channels in the central pacemaker process and highlight new aspects of the contribution of HCN channels to stabilizing the electrical activity of the sinoatrial node network, especially during heart rate regulation by the autonomic nervous system.
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Affiliation(s)
- Konstantin Hennis
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, 81377, Munich, Germany
| | - Martin Biel
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, 81377, Munich, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, 80802, Munich, Germany
| | - Christian Wahl-Schott
- Hannover Medical School, Institute for Neurophysiology, 30625, Hannover, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, 80802, Munich, Germany.
| | - Stefanie Fenske
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, 81377, Munich, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, 80802, Munich, Germany.
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28
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Hassinen M, Dzhumaniiazova I, Abramochkin DV, Vornanen M. Ionic basis of atrioventricular conduction: ion channel expression and sarcolemmal ion currents of the atrioventricular canal of the rainbow trout (Oncorhynchus mykiss) heart. J Comp Physiol B 2021; 191:327-346. [PMID: 33575867 PMCID: PMC7895799 DOI: 10.1007/s00360-021-01344-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 12/15/2020] [Accepted: 01/18/2021] [Indexed: 12/17/2022]
Abstract
Atrioventricular (AV) nodal tissue synchronizes activities of atria and ventricles of the vertebrate heart and is also a potential site of cardiac arrhythmia, e.g., under acute heat stress. Since ion channel composition and ion currents of the fish AV canal have not been previously studied, we measured major cation currents and transcript expression of ion channels in rainbow trout (Oncorhynchus mykiss) AV tissue. Both ion current densities and expression of ion channel transcripts indicate that the fish AV canal has a characteristic electrophysiological phenotype that differs from those of sinoatrial tissue, atrium and ventricle. Two types of cardiomyocytes were distinguished electrophysiologically in trout AV nodal tissue: the one (transitional cell) is functionally intermediate between working atrial/ventricular myocytes and the other (AV nodal cell) has a less negative resting membrane potential than atrial and ventricular myocytes and is a more similar to the sinoatrial nodal cells in ion channel composition. The AV nodal cells are characterized by a small or non-existent inward rectifier potassium current (IK1), low density of fast sodium current (INa) and relatively high expression of T-type calcium channels (CACNA3.1). Pacemaker channel (HCN4 and HCN2) transcripts were expressed in the AV nodal tissue but If current was not found in enzymatically isolated nodal myocytes. The electrophysiological properties of the rainbow trout nodal cells are appropriate for a slow rate of action potential conduction (small INa) and a moderate propensity for pacemaking activity (absence of IK1).
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Affiliation(s)
- Minna Hassinen
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 111, 80101, Joensuu, Finland
| | - Irina Dzhumaniiazova
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia
| | - Denis V Abramochkin
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia.,Laboratory of Cardiac Electrophysiology, National Medical Research Center for Cardiology, Moscow, Russia.,Department of Physiology, Pirogov Russian National Research Medical University, Moscow, Russia
| | - Matti Vornanen
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 111, 80101, Joensuu, Finland.
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29
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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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30
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Liang D, Xue J, Geng L, Zhou L, Lv B, Zeng Q, Xiong K, Zhou H, Xie D, Zhang F, Liu J, Liu Y, Li L, Yang J, Xue Z, Chen YH. Cellular and molecular landscape of mammalian sinoatrial node revealed by single-cell RNA sequencing. Nat Commun 2021; 12:287. [PMID: 33436583 PMCID: PMC7804277 DOI: 10.1038/s41467-020-20448-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 12/03/2020] [Indexed: 02/07/2023] Open
Abstract
Bioelectrical impulses intrinsically generated within the sinoatrial node (SAN) trigger the contraction of the heart in mammals. Though discovered over a century ago, the molecular and cellular features of the SAN that underpin its critical function in the heart are uncharted territory. Here, we identify four distinct transcriptional clusters by single-cell RNA sequencing in the mouse SAN. Functional analysis of differentially expressed genes identifies a core cell cluster enriched in the electrogenic genes. The similar cellular features are also observed in the SAN from both rabbit and cynomolgus monkey. Notably, Vsnl1, a core cell cluster marker in mouse, is abundantly expressed in SAN, but is barely detectable in atrium or ventricle, suggesting that Vsnl1 is a potential SAN marker. Importantly, deficiency of Vsnl1 not only reduces the beating rate of human induced pluripotent stem cell - derived cardiomyocytes (hiPSC-CMs) but also the heart rate of mice. Furthermore, weighted gene co-expression network analysis (WGCNA) unveiled the core gene regulation network governing the function of the SAN in mice. Overall, these findings reveal the whole transcriptome profiling of the SAN at single-cell resolution, representing an advance toward understanding of both the biology and the pathology of SAN. The spontaneous bioelectrical activity of pacemaker cells in sinoatrial node (SAN) triggers the heartbeats. Here, the authors perform single-cell RNA sequencing in the mouse SAN and identify molecular and cellular features of the SAN conserved in rabbit and cynomolgus monkey, identifying a new potential SAN marker.
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Affiliation(s)
- Dandan Liang
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Institute of Medical Genetics, Tongji University, Shanghai, 200092, China
| | - Jinfeng Xue
- Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, 200092, China
| | - Li Geng
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Institute of Medical Genetics, Tongji University, Shanghai, 200092, China
| | - Liping Zhou
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Institute of Medical Genetics, Tongji University, Shanghai, 200092, China
| | - Bo Lv
- Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, 200092, China
| | - Qiao Zeng
- Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, 200092, China
| | - Ke Xiong
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Institute of Medical Genetics, Tongji University, Shanghai, 200092, China
| | - Huixing Zhou
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Institute of Medical Genetics, Tongji University, Shanghai, 200092, China
| | - Duanyang Xie
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Institute of Medical Genetics, Tongji University, Shanghai, 200092, China
| | - Fulei Zhang
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Institute of Medical Genetics, Tongji University, Shanghai, 200092, China
| | - Jie Liu
- Translational Center of Stem Cell Research, Tongji Hospital, Tongji University School of Medicine, Shanghai, 200065, China
| | - Yi Liu
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Institute of Medical Genetics, Tongji University, Shanghai, 200092, China
| | - Li Li
- Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Institute of Medical Genetics, Tongji University, Shanghai, 200092, China.,Department of Pathology and Pathophysiology, Tongji University School of Medicine, Shanghai, 200092, China
| | - Jian Yang
- Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.,Institute of Medical Genetics, Tongji University, Shanghai, 200092, China.,Department of Pathology and Pathophysiology, Tongji University School of Medicine, Shanghai, 200092, China
| | - Zhigang Xue
- Department of Regenerative Medicine, Tongji University School of Medicine, Shanghai, 200092, China. .,Reproductive Medicine Center, Tongji Hospital, Tongji University School of Medicine, Shanghai, 200065, China.
| | - Yi-Han Chen
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China. .,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China. .,Institute of Medical Genetics, Tongji University, Shanghai, 200092, China. .,Department of Pathology and Pathophysiology, Tongji University School of Medicine, Shanghai, 200092, China.
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31
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Weisbrod D. Small and Intermediate Calcium Activated Potassium Channels in the Heart: Role and Strategies in the Treatment of Cardiovascular Diseases. Front Physiol 2020; 11:590534. [PMID: 33329039 PMCID: PMC7719780 DOI: 10.3389/fphys.2020.590534] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Accepted: 10/02/2020] [Indexed: 12/11/2022] Open
Abstract
Calcium-activated potassium channels are a heterogeneous family of channels that, despite their different biophysical characteristics, structures, and pharmacological signatures, play a role of transducer between the ubiquitous intracellular calcium signaling and the electric variations of the membrane. Although this family of channels was extensively described in various excitable and non-excitable tissues, an increasing amount of evidences shows their functional role in the heart. This review aims to focus on the physiological role and the contribution of the small and intermediate calcium-activated potassium channels in cardiac pathologies.
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32
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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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33
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Identification and Characterization of a Transcribed Distal Enhancer Involved in Cardiac Kcnh2 Regulation. Cell Rep 2020; 28:2704-2714.e5. [PMID: 31484079 DOI: 10.1016/j.celrep.2019.08.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 06/05/2019] [Accepted: 07/30/2019] [Indexed: 12/26/2022] Open
Abstract
The human ether-a-go-go-related gene KCNH2 encodes the voltage-gated potassium channel underlying IKr, a current critical for the repolarization phase of the cardiac action potential. Mutations in KCNH2 that cause a reduction of the repolarizing current can result in cardiac arrhythmias associated with long-QT syndrome. Here, we investigate the regulation of KCNH2 and identify multiple active enhancers. A transcribed enhancer ∼85 kbp downstream of Kcnh2 physically contacts the promoters of two Kcnh2 isoforms in a cardiac-specific manner in vivo. Knockdown of its ncRNA transcript results in reduced expression of Kcnh2b and two neighboring mRNAs, Nos3 and Abcb8, in vitro. Genomic deletion of the enhancer, including the ncRNA transcription start site, from the mouse genome causes a modest downregulation of both Kcnh2a and Kcnh2b in the ventricles. These findings establish that the regulation of Kcnh2a and Kcnh2b is governed by a complex regulatory landscape that involves multiple partially redundantly acting enhancers.
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34
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Mohan RA, Bosada FM, van Weerd JH, van Duijvenboden K, Wang J, Mommersteeg MTM, Hooijkaas IB, Wakker V, de Gier-de Vries C, Coronel R, Boink GJJ, Bakkers J, Barnett P, Boukens BJ, Christoffels VM. T-box transcription factor 3 governs a transcriptional program for the function of the mouse atrioventricular conduction system. Proc Natl Acad Sci U S A 2020; 117:18617-18626. [PMID: 32675240 PMCID: PMC7414162 DOI: 10.1073/pnas.1919379117] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Genome-wide association studies have identified noncoding variants near TBX3 that are associated with PR interval and QRS duration, suggesting that subtle changes in TBX3 expression affect atrioventricular conduction system function. To explore whether and to what extent the atrioventricular conduction system is affected by Tbx3 dose reduction, we first characterized electrophysiological properties and morphology of heterozygous Tbx3 mutant (Tbx3+/-) mouse hearts. We found PR interval shortening and prolonged QRS duration, as well as atrioventricular bundle hypoplasia after birth in heterozygous mice. The atrioventricular node size was unaffected. Transcriptomic analysis of atrioventricular nodes isolated by laser capture microdissection revealed hundreds of deregulated genes in Tbx3+/- mutants. Notably, Tbx3+/- atrioventricular nodes showed increased expression of working myocardial gene programs (mitochondrial and metabolic processes, muscle contractility) and reduced expression of pacemaker gene programs (neuronal, Wnt signaling, calcium/ion channel activity). By integrating chromatin accessibility profiles (ATAC sequencing) of atrioventricular tissue and other epigenetic data, we identified Tbx3-dependent atrioventricular regulatory DNA elements (REs) on a genome-wide scale. We used transgenic reporter assays to determine the functionality of candidate REs near Ryr2, an up-regulated chamber-enriched gene, and in Cacna1g, a down-regulated conduction system-specific gene. Using genome editing to delete candidate REs, we showed that a strong intronic bipartite RE selectively governs Cacna1g expression in the conduction system in vivo. Our data provide insights into the multifactorial Tbx3-dependent transcriptional network that regulates the structure and function of the cardiac conduction system, which may underlie the differences in PR duration and QRS interval between individuals carrying variants in the TBX3 locus.
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Affiliation(s)
- Rajiv A Mohan
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Department of Clinical and Experimental Cardiology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Fernanda M Bosada
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Jan H van Weerd
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Karel van Duijvenboden
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Jianan Wang
- Department of Clinical and Experimental Cardiology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Mathilda T M Mommersteeg
- Burdon Sanderson Cardiac Science Centre, Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
| | - Ingeborg B Hooijkaas
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Vincent Wakker
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Corrie de Gier-de Vries
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Ruben Coronel
- Department of Clinical and Experimental Cardiology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Gerard J J Boink
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Department of Clinical and Experimental Cardiology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Jeroen Bakkers
- Hubrecht Institute and University Medical Center Utrecht, 3584 CT Utrecht, the Netherlands
| | - Phil Barnett
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Bas J Boukens
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Department of Clinical and Experimental Cardiology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Vincent M Christoffels
- Department of Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands;
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35
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Abstract
Voltage-gated Kv1.1 potassium channel α-subunits are broadly expressed in the nervous system where they act as critical regulators of neuronal excitability. Mutations in the KCNA1 gene, which encodes Kv1.1, are associated with the neurological diseases episodic ataxia and epilepsy. Studies in mouse models have shown that Kv1.1 is important for neural control of the heart and that Kcna1 deletion leads to cardiac dysfunction that appears to be brain-driven. Traditionally, KCNA1 was not believed to be expressed in the heart. However, recent studies have revealed that Kv1.1 subunits are not only present in cardiomyocytes, but that they also make an important heart-intrinsic functional contribution to outward K+ currents and action potential repolarization. This review recounts the winding history of discovery of KCNA1 gene expression and neurocardiac function from fruit flies to mammals and from brain to heart and looks at some of the salient questions that remain to be answered regarding emerging cardiac roles of Kv1.1.
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Affiliation(s)
- Edward Glasscock
- a Department of Biological Sciences , Southern Methodist University , Dallas , TX , USA
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36
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Sutcliffe RL, Li S, Gilbert MJH, Schulte PM, Miller KM, Farrell AP. A rapid intrinsic heart rate resetting response with thermal acclimation in rainbow trout, Oncorhynchus mykiss. J Exp Biol 2020; 223:jeb215210. [PMID: 32345705 PMCID: PMC7328139 DOI: 10.1242/jeb.215210] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Accepted: 04/17/2020] [Indexed: 01/01/2023]
Abstract
We examined cardiac pacemaker rate resetting in rainbow trout following a reciprocal temperature transfer. In the original experiment, performed in winter, 4°C-acclimated fish transferred to 12°C reset intrinsic heart rate after just 1 h (from 56.8±1.2 to 50.8±1.5 beats min-1); 12°C-acclimated fish transferred to 4°C reset intrinsic heart rate after 8 h (from 33.4±0.7 to 37.7±1.2 beats min-1). However, in a replicate experiment, performed in the summer using a different brood year, intrinsic heart rate was not reset, even after 10 weeks at a new temperature. Using this serendipitous opportunity, we compared mRNA expression changes of a suite of proteins in sinoatrial node (SAN), atrial and ventricular tissues after both 1 h and longer than 3 weeks for both experimental acclimation groups to identify those changes only associated with pacemaker rate resetting. Of the changes in mRNA expression occurring after more than 3 weeks of warm acclimation and associated with pacemaker rate resetting, we observed downregulation of NKA α1c in the atrium and ventricle, and upregulation of HCN1 in the ventricle. However, in the SAN there were no mRNA expression changes unique to the fish with pacemaker rate resetting after either 1 h or 3 weeks of warm acclimation. Thus, despite identifying changes in mRNA expression of contractile cardiac tissues, there was an absence of changes in mRNA expression directly involved with the initial, rapid pacemaker rate resetting with warm acclimation. Importantly, pacemaker rate resetting with thermal acclimation does not always occur in rainbow trout.
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Affiliation(s)
- Rachel L Sutcliffe
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Shaorong Li
- Pacific Biological Station, Fisheries and Oceans, Nanaimo, BC, Canada, V9T 6N7
| | - Matthew J H Gilbert
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Patricia M Schulte
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Kristi M Miller
- Pacific Biological Station, Fisheries and Oceans, Nanaimo, BC, Canada, V9T 6N7
| | - Anthony P Farrell
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
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37
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Regulation of cardiovascular calcium channel activity by post-translational modifications or interacting proteins. Pflugers Arch 2020; 472:653-667. [PMID: 32435990 DOI: 10.1007/s00424-020-02398-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 05/04/2020] [Accepted: 05/06/2020] [Indexed: 02/08/2023]
Abstract
Voltage-gated calcium channels are the major pathway for Ca2+ influx to initiate the contraction of smooth and cardiac muscles. Alterations of calcium channel function have been implicated in multiple cardiovascular diseases, such as hypertension, atrial fibrillation, and long QT syndrome. Post-translational modifications do expand cardiovascular calcium channel structure and function to affect processes such as channel trafficking or polyubiquitination by two E3 ubiquitin ligases, Ret finger protein 2 (Rfp2) or murine double minute 2 protein (Mdm2). Additionally, biophysical property such as Ca2+-dependent inactivation (CDI) could be altered through binding of calmodulin, or channel activity could be modulated via S-nitrosylation by nitric oxide and phosphorylation by protein kinases or by interacting protein partners, such as galectin-1 and Rem. Understanding how cardiovascular calcium channel function is post-translationally remodeled under distinctive disease conditions will provide better information about calcium channel-related disease mechanisms and improve the development of more selective therapeutic agents for cardiovascular diseases.
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38
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Gradual differentiation and confinement of the cardiac conduction system as indicated by marker gene expression. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118509. [DOI: 10.1016/j.bbamcr.2019.07.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 07/05/2019] [Accepted: 07/09/2019] [Indexed: 11/23/2022]
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39
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Abdelnabi M, Ahmed A, Almaghraby A, Saleh Y, Badran H. Ivabradine and AF: Coincidence, Correlation or a New Treatment? Arrhythm Electrophysiol Rev 2020; 8:300-303. [PMID: 32685161 PMCID: PMC7358942 DOI: 10.15420/aer.2019.30.2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Ivabradine is a heart rate-lowering agent that inhibits pacemaker funny current (If). It has been approved by the European Medicines Agency and the US Food and Drug Administration for patients with stable angina and heart failure (HF). AF is a common issue especially in ischaemic heart disease and HF patients. In contrast to experimental findings and a limited number of clinical trials that demonstrate the emerging role of ivabradine for heart rate control in AF or maintenance of sinus rhythm, there is accumulating contradictory data indicating that there is, in fact, an increased incidence of new-onset AF among people who are taking ivabradine in clinical practice. This article reviews the most recent evidence highlighting the diversity of data in relation to the use of ivabradine and the onset of AF and whether it has a legitimate role in AF treatment and the maintenance of sinus rhythm.
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Affiliation(s)
- Mahmoud Abdelnabi
- Cardiology and Angiology Unit, Department of Clinical and Experimental Internal Medicine, Medical Research Institute, University of Alexandria, Egypt
| | - Ashraf Ahmed
- Department of Cardiology, Faculty of Medicine, University of Alexandria, Egypt
| | - Abdallah Almaghraby
- Department of Cardiology, Faculty of Medicine, University of Alexandria, Egypt
| | - Yehia Saleh
- Department of Cardiology, Faculty of Medicine, University of Alexandria, Egypt.,Michigan State University, East Lansing, MI, US
| | - Haitham Badran
- Department of Cardiology, Faculty of Medicine, Ain Shams University, Cairo, Egypt
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40
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Liang W, Han P, Kim EH, Mak J, Zhang R, Torrente AG, Goldhaber JI, Marbán E, Cho HC. Canonical Wnt signaling promotes pacemaker cell specification of cardiac mesodermal cells derived from mouse and human embryonic stem cells. Stem Cells 2019; 38:352-368. [PMID: 31648393 DOI: 10.1002/stem.3106] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 08/30/2019] [Indexed: 01/03/2023]
Abstract
Cardiac differentiation of embryonic stem cells (ESCs) can give rise to de novo chamber cardiomyocytes and nodal pacemaker cells. Compared with our understanding of direct differentiation toward atrial and ventricular myocytes, the mechanisms for nodal pacemaker cell commitment are not well understood. Taking a cue from the prominence of canonical Wnt signaling during cardiac pacemaker tissue development in chick embryos, we asked if modulations of Wnt signaling influence cardiac progenitors to bifurcate to either chamber cardiomyocytes or pacemaker cells. Omitting an exogenous Wnt inhibitor, which is routinely added to maximize cardiac myocyte yield during differentiation of mouse and human ESCs, led to increased yield of spontaneously beating cardiomyocytes with action potential properties similar to those of native sinoatrial node pacemaker cells. The pacemaker phenotype was accompanied by enhanced expression of genes and gene products that mark nodal pacemaker cells such as Hcn4, Tbx18, Tbx3, and Shox2. Addition of exogenous Wnt3a ligand, which activates canonical Wnt/β-catenin signaling, increased the yield of pacemaker-like myocytes while reducing cTNT-positive pan-cardiac differentiation. Conversely, addition of inhibitors of Wnt/β-catenin signaling led to increased chamber myocyte lineage development at the expense of pacemaker cell specification. The positive impact of canonical Wnt signaling on nodal pacemaker cell differentiation was evidenced in direct differentiation of two human ESC lines and human induced pluripotent stem cells. Our data identify the Wnt/β-catenin pathway as a critical determinant of cardiac myocyte subtype commitment during ESC differentiation: endogenous Wnt signaling favors the pacemaker lineage, whereas its suppression promotes the chamber cardiomyocyte lineage.
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Affiliation(s)
- Wenbin Liang
- University of Ottawa Heart Institute and Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Pengcheng Han
- Department of Pediatrics, Emory University, Atlanta, Georgia
| | - Elizabeth H Kim
- Department of Pediatrics, Emory University, Atlanta, Georgia
| | - Jordan Mak
- Department of Pediatrics, Emory University, Atlanta, Georgia
| | - Rui Zhang
- Cedars-Sinai Heart Institute, Los Angeles, California
| | | | | | | | - Hee Cheol Cho
- Department of Pediatrics, Emory University, Atlanta, Georgia.,Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia
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41
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Northcutt AJ, Schulz DJ. Molecular mechanisms of homeostatic plasticity in central pattern generator networks. Dev Neurobiol 2019; 80:58-69. [PMID: 31778295 DOI: 10.1002/dneu.22727] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 10/09/2019] [Accepted: 11/22/2019] [Indexed: 01/27/2023]
Abstract
Central pattern generator (CPG) networks rely on a balance of intrinsic and network properties to produce reliable, repeatable activity patterns. This balance is maintained by homeostatic plasticity where alterations in neuronal properties dynamically maintain appropriate neural output in the face of changing environmental conditions and perturbations. However, it remains unclear just how these neurons and networks can both monitor their ongoing activity and use this information to elicit homeostatic physiological responses to ensure robustness of output over time. Evidence exists that CPG networks use a mixed strategy of activity-dependent, activity-independent, modulator-dependent, and synaptically regulated homeostatic plasticity to achieve this critical stability. In this review, we focus on some of the current understanding of the molecular pathways and mechanisms responsible for this homeostatic plasticity in the context of central pattern generator function, with a special emphasis on some of the smaller invertebrate networks that have allowed for extensive cellular-level analyses that have brought recent insights to these questions.
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Affiliation(s)
- Adam J Northcutt
- Division of Biological Sciences, University of Missouri-Columbia, Columbia, Missouri
| | - David J Schulz
- Division of Biological Sciences, University of Missouri-Columbia, Columbia, Missouri
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42
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Wang F, Zhao H, Yin L, Tang Y, Wang X, Zhao Q, Wang T, Huang C. Transcription Factor TBX18 Reprograms Vascular Smooth Muscle Cells of Ascending Aorta to Pacemaker-Like Cells. DNA Cell Biol 2019; 38:1470-1479. [PMID: 31633376 DOI: 10.1089/dna.2019.4940] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Vascular smooth muscle cells (VSMCs) of ascending aorta and TBX18+ sinus node both originated from the second heart field. The study explored whether ascending aortic smooth muscle cells in vitro could be reprogrammed into pacemaker-like cells with human TBX18. In the study, VSMCs were infected with TBX18, and then cocultured with neonatal rat ventricular cardiomyocytes (NRVMs) in vitro. By overexpressing TBX18, the transfected VSMCs expressed high levels of hyperpolarization-activated cyclic nucleotide-gated channel 4 (HCN4), insulin gene enhancer binding protein 1, and human dwarf homeobox gene SHOX2, cardiac troponin I, and low level of connexin 43. In addition, funny current (If) was recorded by patch clamp appeared the time and voltage dependence in TBX18 group, which the amplitude of If density was from -5.164 ± 0.662 pA/pF to -0.765 ± 0.358 pA/pF (n = 14). Furthermore, TBX18-transfected VSMCs coupled with NRVMs showed typical action potential of pacemaker-like cells and the beating rate was faster (178.00 ± 7.55 bpm, p < 0.05) compared with other groups. In conclusion, our study indicated that transcription factor TBX18 could reprogram VSMCs into pacemaker-like cells in vitro.
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Affiliation(s)
- Fengyuan Wang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, Wuhan, People's Republic of China.,Hubei Key Laboratory of Cardiology, Wuhan, People's Republic of China
| | - Hongyi Zhao
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, Wuhan, People's Republic of China.,Hubei Key Laboratory of Cardiology, Wuhan, People's Republic of China
| | - Lin Yin
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, Wuhan, People's Republic of China.,Hubei Key Laboratory of Cardiology, Wuhan, People's Republic of China
| | - Yanhong Tang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, Wuhan, People's Republic of China.,Hubei Key Laboratory of Cardiology, Wuhan, People's Republic of China
| | - Xi Wang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, Wuhan, People's Republic of China.,Hubei Key Laboratory of Cardiology, Wuhan, People's Republic of China
| | - Qingyan Zhao
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, Wuhan, People's Republic of China.,Hubei Key Laboratory of Cardiology, Wuhan, People's Republic of China
| | - Teng Wang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, Wuhan, People's Republic of China.,Hubei Key Laboratory of Cardiology, Wuhan, People's Republic of China
| | - Congxin Huang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, People's Republic of China.,Cardiovascular Research Institute, Wuhan University, Wuhan, People's Republic of China.,Hubei Key Laboratory of Cardiology, Wuhan, People's Republic of China
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Delisle BP, Yu Y, Puvvula P, Hall AR, Huff C, Moon AM. Tbx3-Mediated Regulation of Cardiac Conduction System Development and Function: Potential Contributions of Alternative RNA Processing. Pediatr Cardiol 2019; 40:1388-1400. [PMID: 31372681 DOI: 10.1007/s00246-019-02166-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 07/18/2019] [Indexed: 11/28/2022]
Abstract
In this article, we provide a brief summary of work by us and others to discover the molecular underpinnings of early conduction system development and function. We focus on how the multifunctional protein Tbx3 contributes to acquisition and homeostasis of the tissue-specific properties of the sinoatrial and atrioventricular nodes. We also provide unpublished, preliminary findings supporting the role of Tbx3-regulated alternative RNA processing in the developing conduction system.
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Affiliation(s)
- Brian P Delisle
- Department of Physiology, University of Kentucky School of Medicine, Lexington, KY, USA
| | - Yao Yu
- Department of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Pavan Puvvula
- Department of Molecular and Functional Genomics, Weis Center for Research, Geisinger Clinic, 100 North Academy Ave 26-18, Danville, PA, 17822, USA
| | - Allison R Hall
- Department of Physiology, University of Kentucky School of Medicine, Lexington, KY, USA
| | - Chad Huff
- Department of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Anne M Moon
- Department of Molecular and Functional Genomics, Weis Center for Research, Geisinger Clinic, 100 North Academy Ave 26-18, Danville, PA, 17822, USA. .,Departments of Pediatrics and Human Genetics, University of Utah School of Medicine, Salt Lake City, UT, USA.
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44
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Goodyer WR, Beyersdorf BM, Paik DT, Tian L, Li G, Buikema JW, Chirikian O, Choi S, Venkatraman S, Adams EL, Tessier-Lavigne M, Wu JC, Wu SM. Transcriptomic Profiling of the Developing Cardiac Conduction System at Single-Cell Resolution. Circ Res 2019; 125:379-397. [PMID: 31284824 DOI: 10.1161/circresaha.118.314578] [Citation(s) in RCA: 99] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
RATIONALE The cardiac conduction system (CCS) consists of distinct components including the sinoatrial node, atrioventricular node, His bundle, bundle branches, and Purkinje fibers. Despite an essential role for the CCS in heart development and function, the CCS has remained challenging to interrogate because of inherent obstacles including small cell numbers, large cell-type heterogeneity, complex anatomy, and difficulty in isolation. Single-cell RNA-sequencing allows for genome-wide analysis of gene expression at single-cell resolution. OBJECTIVE Assess the transcriptional landscape of the entire CCS at single-cell resolution by single-cell RNA-sequencing within the developing mouse heart. METHODS AND RESULTS Wild-type, embryonic day 16.5 mouse hearts (n=6 per zone) were harvested and 3 zones of microdissection were isolated, including: Zone I-sinoatrial node region; Zone II-atrioventricular node/His region; and Zone III-bundle branch/Purkinje fiber region. Tissue was digested into single-cell suspensions, cells isolated, mRNA reverse transcribed, and barcoded before high-throughput sequencing and bioinformatics analyses. Single-cell RNA-sequencing was performed on over 22 000 cells, and all major cell types of the murine heart were successfully captured including bona fide clusters of cells consistent with each major component of the CCS. Unsupervised weighted gene coexpression network analysis led to the discovery of a host of novel CCS genes, a subset of which were validated using fluorescent in situ hybridization as well as whole-mount immunolabeling with volume imaging (iDISCO+) in 3 dimensions on intact mouse hearts. Further, subcluster analysis unveiled isolation of distinct CCS cell subtypes, including the clinically relevant but poorly characterized transitional cells that bridge the CCS and surrounding myocardium. CONCLUSIONS Our study represents the first comprehensive assessment of the transcriptional profiles from the entire CCS at single-cell resolution and provides a characterization in the context of development and disease.
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Affiliation(s)
- William R Goodyer
- From the Cardiovascular Institute (W.R.G., B.M.B., D.T.P., L.T., G.L., J.W.B., O.C., S.C., S.V., J.C.W., S.M.W.), Stanford University School of Medicine, CA.,Department of Pediatrics (W.R.G., S.M.W.), Stanford University, CA
| | - Benjamin M Beyersdorf
- From the Cardiovascular Institute (W.R.G., B.M.B., D.T.P., L.T., G.L., J.W.B., O.C., S.C., S.V., J.C.W., S.M.W.), Stanford University School of Medicine, CA.,Department of Cardiovascular Surgery, Institute Insure (Institute for Translational Cardiac Surgery), German Heart Center Munich at the Technical University of Munich, Germany (B.M.B.)
| | - David T Paik
- From the Cardiovascular Institute (W.R.G., B.M.B., D.T.P., L.T., G.L., J.W.B., O.C., S.C., S.V., J.C.W., S.M.W.), Stanford University School of Medicine, CA
| | - Lei Tian
- From the Cardiovascular Institute (W.R.G., B.M.B., D.T.P., L.T., G.L., J.W.B., O.C., S.C., S.V., J.C.W., S.M.W.), Stanford University School of Medicine, CA
| | - Guang Li
- From the Cardiovascular Institute (W.R.G., B.M.B., D.T.P., L.T., G.L., J.W.B., O.C., S.C., S.V., J.C.W., S.M.W.), Stanford University School of Medicine, CA.,Department of Developmental Biology, University of Pittsburgh School of Medicine, PA (G.L.)
| | - Jan W Buikema
- From the Cardiovascular Institute (W.R.G., B.M.B., D.T.P., L.T., G.L., J.W.B., O.C., S.C., S.V., J.C.W., S.M.W.), Stanford University School of Medicine, CA.,Department of Cardiology, Utrecht Regenerative Medicine Center, University Medical Center Utrecht, Utrecht University, The Netherlands (J.W.B.)
| | - Orlando Chirikian
- From the Cardiovascular Institute (W.R.G., B.M.B., D.T.P., L.T., G.L., J.W.B., O.C., S.C., S.V., J.C.W., S.M.W.), Stanford University School of Medicine, CA.,Department of Molecular, Cellular, and Developmental Biology, UC Santa Barbara, CA (O.C.)
| | - Shannon Choi
- From the Cardiovascular Institute (W.R.G., B.M.B., D.T.P., L.T., G.L., J.W.B., O.C., S.C., S.V., J.C.W., S.M.W.), Stanford University School of Medicine, CA
| | - Sneha Venkatraman
- From the Cardiovascular Institute (W.R.G., B.M.B., D.T.P., L.T., G.L., J.W.B., O.C., S.C., S.V., J.C.W., S.M.W.), Stanford University School of Medicine, CA
| | - Eliza L Adams
- Department of Biology (E.L.A., M.T.-L.), Stanford University, CA
| | | | - Joseph C Wu
- From the Cardiovascular Institute (W.R.G., B.M.B., D.T.P., L.T., G.L., J.W.B., O.C., S.C., S.V., J.C.W., S.M.W.), Stanford University School of Medicine, CA.,Department of Medicine, Cardiovascular Medicine (J.C.W., S.M.W.), Stanford University School of Medicine, CA
| | - Sean M Wu
- From the Cardiovascular Institute (W.R.G., B.M.B., D.T.P., L.T., G.L., J.W.B., O.C., S.C., S.V., J.C.W., S.M.W.), Stanford University School of Medicine, CA.,Department of Medicine, Cardiovascular Medicine (J.C.W., S.M.W.), Stanford University School of Medicine, CA.,Department of Pediatrics (W.R.G., S.M.W.), Stanford University, CA
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45
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Darche FF, Rivinius R, Köllensperger E, Leimer U, Germann G, Seckinger A, Hose D, Schröter J, Bruehl C, Draguhn A, Gabriel R, Schmidt M, Koenen M, Thomas D, Katus HA, Schweizer PA. Pacemaker cell characteristics of differentiated and HCN4-transduced human mesenchymal stem cells. Life Sci 2019; 232:116620. [PMID: 31291594 DOI: 10.1016/j.lfs.2019.116620] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 06/21/2019] [Accepted: 06/29/2019] [Indexed: 12/13/2022]
Abstract
AIMS Cell-based biological pacemakers aim to overcome limitations and side effects of electronic pacemaker devices. We here developed and tested different approaches to achieve nodal-type differentiation using human adipose- and bone marrow-derived mesenchymal stem cells (haMSC, hbMSC). MAIN METHODS haMSC and hbMSC were differentiated using customized protocols. Quantitative RT-PCR was applied for transcriptional pacemaker-gene profiling. Protein membrane expression was analyzed by immunocytochemistry. Pacemaker current (If) was studied in haMSC with and without lentiviral HCN4-transduction using patch clamp recordings. Functional characteristics were evaluated by co-culturing with neonatal rat ventricular myocytes (NRVM). KEY FINDINGS Culture media-based differentiation for two weeks generated cells with abundant transcription of ion channel genes (Cav1.2, NCX1), transcription factors (TBX3, TBX18, SHOX2) and connexins (Cx31.9 and Cx45) characteristic for cardiac pacemaker tissue, but lack adequate HCN transcription. haMSC-derived cells revealed transcript levels, which were closer related to sinoatrial nodal cells than hbMSC-derived cells. To substitute for the lack of If, we performed lentiviral HCN4-transduction of haMSC resulting in stable If. Co-culturing with NRVM demonstrated that differentiated haMSC expressing HCN4 showed earlier onset of spontaneous contractions and higher beating regularity, synchrony and rate compared to co-cultures with non-HCN4-transduced haMSC or HCN4-transduced, non-differentiated haMSC. Confocal imaging indicated increased membrane expression of cardiac gap junctional proteins in differentiated haMSC. SIGNIFICANCE By differentiation haMSC, rather than hbMSC attain properties favorable for cardiac pacemaking. In combination with lentiviral HCN4-transduction, a cellular phenotype was generated that sustainably controls and stabilizes rate in co-culture with NRVM.
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Affiliation(s)
- Fabrice F Darche
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany
| | - Rasmus Rivinius
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany
| | - Eva Köllensperger
- ETHIANUM Klinik Heidelberg, Voßstraße 6, D-69115 Heidelberg, Germany
| | - Uwe Leimer
- ETHIANUM Klinik Heidelberg, Voßstraße 6, D-69115 Heidelberg, Germany
| | - Günter Germann
- ETHIANUM Klinik Heidelberg, Voßstraße 6, D-69115 Heidelberg, Germany
| | - Anja Seckinger
- Department of Hematology, Oncology and Rheumatology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany
| | - Dirk Hose
- Department of Hematology, Oncology and Rheumatology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany
| | - Julian Schröter
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany
| | - Claus Bruehl
- Institute for Physiology and Pathophysiology, University of Heidelberg, INF 326, D-69120 Heidelberg, Germany
| | - Andreas Draguhn
- Institute for Physiology and Pathophysiology, University of Heidelberg, INF 326, D-69120 Heidelberg, Germany
| | - Richard Gabriel
- Molecular and Gene Therapy, National Center for Tumor Diseases (NCT) Heidelberg, INF 460, D-69120 Heidelberg, Germany
| | - Manfred Schmidt
- Molecular and Gene Therapy, National Center for Tumor Diseases (NCT) Heidelberg, INF 460, D-69120 Heidelberg, Germany
| | - Michael Koenen
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany; Department of Molecular Neurobiology, Max-Planck-Institute for Medical Research, Jahnstrasse 29, D-69120 Heidelberg, Germany
| | - Dierk Thomas
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany; DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, INF 410, D-69120 Heidelberg, Germany
| | - Hugo A Katus
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany; DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, INF 410, D-69120 Heidelberg, Germany
| | - Patrick A Schweizer
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany; DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, INF 410, D-69120 Heidelberg, Germany.
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46
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Linscheid N, Logantha SJRJ, Poulsen PC, Zhang S, Schrölkamp M, Egerod KL, Thompson JJ, Kitmitto A, Galli G, Humphries MJ, Zhang H, Pers TH, Olsen JV, Boyett M, Lundby A. Quantitative proteomics and single-nucleus transcriptomics of the sinus node elucidates the foundation of cardiac pacemaking. Nat Commun 2019; 10:2889. [PMID: 31253831 PMCID: PMC6599035 DOI: 10.1038/s41467-019-10709-9] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 05/28/2019] [Indexed: 12/13/2022] Open
Abstract
The sinus node is a collection of highly specialised cells constituting the heart’s pacemaker. The molecular underpinnings of its pacemaking abilities are debated. Using high-resolution mass spectrometry, we here quantify >7,000 proteins from sinus node and neighbouring atrial muscle. Abundances of 575 proteins differ between the two tissues. By performing single-nucleus RNA sequencing of sinus node biopsies, we attribute measured protein abundances to specific cell types. The data reveal significant differences in ion channels responsible for the membrane clock, but not in Ca2+ clock proteins, suggesting that the membrane clock underpins pacemaking. Consistently, incorporation of ion channel expression differences into a biophysically-detailed atrial action potential model result in pacemaking and a sinus node-like action potential. Combining our quantitative proteomics data with computational modeling, we estimate ion channel copy numbers for sinus node myocytes. Our findings provide detailed insights into the unique molecular make-up of the cardiac pacemaker. The sinus node generates rhythmic heartbeat but the molecular basis of pacemaking is still under debate. Here, the authors combine quantitative proteomics and single-nucleus transcriptomics to characterize the molecular composition of the sinus node and provide insights into the underpinnings of pacemaking.
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Affiliation(s)
- Nora Linscheid
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, København, 2200, Denmark
| | | | - Pi Camilla Poulsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, København, 2200, Denmark
| | - Shanzhuo Zhang
- School of Computer Science and Technology, Harbin Institute of Technology, Haerbin Shi, 150006, China
| | - Maren Schrölkamp
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, København, 2200, Denmark
| | - Kristoffer Lihme Egerod
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, København, 2200, Denmark
| | - Jonatan James Thompson
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, København, 2200, Denmark
| | - Ashraf Kitmitto
- Division of Cardiovascular Sciences, University of Manchester, Manchester, M13 9NT, UK
| | - Gina Galli
- Division of Cardiovascular Sciences, University of Manchester, Manchester, M13 9NT, UK
| | - Martin J Humphries
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Biology, Medicine & Health, University of Manchester, Manchester, M13 9PT, UK
| | - Henggui Zhang
- Biological Physics Group, School of Physics & Astronomy, University of Manchester, Manchester, M13 9PL, UK
| | - Tune H Pers
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, København, 2200, Denmark
| | - Jesper Velgaard Olsen
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, København, 2200, Denmark
| | - Mark Boyett
- Division of Cardiovascular Sciences, University of Manchester, Manchester, M13 9NT, UK.
| | - Alicia Lundby
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, København, 2200, Denmark. .,The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, København, 2200, Denmark.
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47
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A randomised, double-blind, placebo-controlled crossover trial of the influence of the HCN channel blocker ivabradine in a healthy volunteer pain model: an enriched population trial. Pain 2019; 160:2554-2565. [DOI: 10.1097/j.pain.0000000000001638] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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48
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Qu YS, Lazzerini PE, Capecchi PL, Laghi-Pasini F, El Sherif N, Boutjdir M. Autoimmune Calcium Channelopathies and Cardiac Electrical Abnormalities. Front Cardiovasc Med 2019; 6:54. [PMID: 31119135 PMCID: PMC6507622 DOI: 10.3389/fcvm.2019.00054] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 04/16/2019] [Indexed: 12/24/2022] Open
Abstract
Patients with autoimmune diseases are at increased risk for developing cardiovascular diseases, and abnormal electrocardiographic findings are common. Voltage-gated calcium channels play a major role in the cardiovascular system and regulate cardiac excitability and contractility. Particularly, by virtue of their localization and expression in the heart, calcium channels modulate pace making at the sinus node, conduction at the atrioventricular node and cardiac repolarization in the working myocardium. Consequently, emerging evidence suggests that calcium channels are targets to autoantibodies in autoimmune diseases. Autoimmune-associated cardiac calcium channelopathies have been recognized in both sinus node dysfunction atrioventricular block in patients positive for anti-Ro/La antibodies, and ventricular arrhythmias in patients with dilated cardiomyopathy. In this review, we discuss mechanisms of autoimmune-associated calcium channelopathies and their relationship with the development of cardiac electrical abnormalities.
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Affiliation(s)
- Yongxia Sarah Qu
- Department of Cardiology, New York Presbyterian Brooklyn Methodist Hospital, Brooklyn, NY, United States.,VA New York Harbor Healthcare System and State University of New York Downstate Medical Center, Brooklyn, NY, United States
| | - Pietro Enea Lazzerini
- Department of Medical Sciences, Surgery and Neurosciences, University of Siena, Siena, Italy
| | - Pier Leopoldo Capecchi
- Department of Medical Sciences, Surgery and Neurosciences, University of Siena, Siena, Italy
| | - Franco Laghi-Pasini
- Department of Medical Sciences, Surgery and Neurosciences, University of Siena, Siena, Italy
| | - Nabil El Sherif
- VA New York Harbor Healthcare System and State University of New York Downstate Medical Center, Brooklyn, NY, United States
| | - Mohamed Boutjdir
- VA New York Harbor Healthcare System and State University of New York Downstate Medical Center, Brooklyn, NY, United States.,NYU School of Medicine, New York, NY, United States
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49
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van Eif VWW, Stefanovic S, van Duijvenboden K, Bakker M, Wakker V, de Gier-de Vries C, Zaffran S, Verkerk AO, Boukens BJ, Christoffels VM. Transcriptome analysis of mouse and human sinoatrial node cells reveals a conserved genetic program. Development 2019; 146:dev.173161. [PMID: 30936179 DOI: 10.1242/dev.173161] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 03/20/2019] [Indexed: 02/03/2023]
Abstract
The rate of contraction of the heart relies on proper development and function of the sinoatrial node, which consists of a small heterogeneous cell population, including Tbx3+ pacemaker cells. Here, we have isolated and characterized the Tbx3+ cells from Tbx3 +/Venus knock-in mice. We studied electrophysiological parameters during development and found that Venus-labeled cells are genuine Tbx3+ pacemaker cells. We analyzed the transcriptomes of late fetal FACS-purified Tbx3+ sinoatrial nodal cells and Nppb-Katushka+ atrial and ventricular chamber cardiomyocytes, and identified a sinoatrial node-enriched gene program, including key nodal transcription factors, BMP signaling and Smoc2, the disruption of which in mice did not affect heart rhythm. We also obtained the transcriptomes of the sinoatrial node region, including pacemaker and other cell types, and right atrium of human fetuses, and found a gene program including TBX3, SHOX2, ISL1 and HOX family members, and BMP and NOTCH signaling components conserved between human and mouse. We conclude that a conserved gene program characterizes the sinoatrial node region and that the Tbx3 +/Venus allele provides a reliable tool for visualizing the sinoatrial node, and studying its development and function.
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Affiliation(s)
- Vincent W W van Eif
- Department of Medical Biology, University of Amsterdam, Amsterdam University Medical Centers, Amsterdam 1105 AZ, The Netherlands
| | - Sonia Stefanovic
- Aix-Marseille University - INSERM U1251, Marseille Medical Genetics, Marseille 13005, France
| | - Karel van Duijvenboden
- Department of Medical Biology, University of Amsterdam, Amsterdam University Medical Centers, Amsterdam 1105 AZ, The Netherlands
| | - Martijn Bakker
- Department of Medical Biology, University of Amsterdam, Amsterdam University Medical Centers, Amsterdam 1105 AZ, The Netherlands
| | - Vincent Wakker
- Department of Medical Biology, University of Amsterdam, Amsterdam University Medical Centers, Amsterdam 1105 AZ, The Netherlands
| | - Corrie de Gier-de Vries
- Department of Medical Biology, University of Amsterdam, Amsterdam University Medical Centers, Amsterdam 1105 AZ, The Netherlands
| | - Stéphane Zaffran
- Aix-Marseille University - INSERM U1251, Marseille Medical Genetics, Marseille 13005, France
| | - Arie O Verkerk
- Department of Medical Biology, University of Amsterdam, Amsterdam University Medical Centers, Amsterdam 1105 AZ, The Netherlands
| | - Bas J Boukens
- Department of Medical Biology, University of Amsterdam, Amsterdam University Medical Centers, Amsterdam 1105 AZ, The Netherlands
| | - Vincent M Christoffels
- Department of Medical Biology, University of Amsterdam, Amsterdam University Medical Centers, Amsterdam 1105 AZ, The Netherlands
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50
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Natriuretic Peptide Receptor-C Protects Against Angiotensin II-Mediated Sinoatrial Node Disease in Mice. JACC Basic Transl Sci 2018; 3:824-843. [PMID: 30623142 PMCID: PMC6314975 DOI: 10.1016/j.jacbts.2018.08.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 08/15/2018] [Accepted: 08/16/2018] [Indexed: 12/19/2022]
Abstract
SAN disease is prevalent in hypertension and heart failure and can be induced by chronic Ang II treatment in mice. Ang II caused SAN disease in mice in association with impaired electrical conduction, reduction in the hyperpolarization-activated current (If) in SAN myocytes, and increased SAN fibrosis. Ang II-induced SAN disease was worsened in mice lacking NPR-C in association with enhanced SAN fibrosis. Mice co-treated with Ang II and an NPR-C agonist (cANF) were protected from SAN disease. NPR-C may represent a new target to protect against Ang II-induced SAN disease.
Sinoatrial node (SAN) disease mechanisms are poorly understood, and therapeutic options are limited. Natriuretic peptide(s) (NP) are cardioprotective hormones whose effects can be mediated partly by the NP receptor C (NPR-C). We investigated the role of NPR-C in angiotensin II (Ang II)-mediated SAN disease in mice. Ang II caused SAN disease due to impaired electrical activity in SAN myocytes and increased SAN fibrosis. Strikingly, Ang II treatment in NPR-C−/− mice worsened SAN disease, whereas co-treatment of wild-type mice with Ang II and a selective NPR-C agonist (cANF) prevented SAN dysfunction. NPR-C may represent a new target to protect against the development of Ang II-induced SAN disease.
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Key Words
- AP, action potential
- Ang II, angiotensin II
- CV, conduction velocity
- DD, diastolic depolarization
- Gmax, maximum conductance
- HR, heart rate
- ICa,L, L-type calcium current
- ICa,T, T-type calcium current
- INCX, sodium–calcium exchanger current
- IV, current voltage relationship
- If, hyperpolarization-activated current
- NP, natriuretic peptide
- NPR, natriuretic peptide receptor
- NPR-C, natriuretic peptide receptor C
- SAN, sinoatrial node
- SBP, systolic blood pressure
- V1/2(act), voltage for 50% channel activation
- cSNRT, corrected sinoatrial node recovery time
- fibrosis
- hypertension
- ion currents
- natriuretic peptide
- sinoatrial node
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