1
|
Lickiss B, Hunker J, Bhagwan J, Linder P, Thomas U, Lotay H, Broadbent S, Dragicevic E, Stoelzle-Feix S, Turner J, Gossmann M. Chamber-specific contractile responses of atrial and ventricular hiPSC-cardiomyocytes to GPCR and ion channel targeting compounds: A microphysiological system for cardiac drug development. J Pharmacol Toxicol Methods 2024; 128:107529. [PMID: 38857637 DOI: 10.1016/j.vascn.2024.107529] [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: 02/26/2024] [Revised: 05/15/2024] [Accepted: 06/05/2024] [Indexed: 06/12/2024]
Abstract
Human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (CMs) have found utility for conducting in vitro drug screening and disease modelling to gain crucial insights into pharmacology or disease phenotype. However, diseases such as atrial fibrillation, affecting >33 M people worldwide, demonstrate the need for cardiac subtype-specific cells. Here, we sought to investigate the base characteristics and pharmacological differences between commercially available chamber-specific atrial or ventricular hiPSC-CMs seeded onto ultra-thin, flexible PDMS membranes to simultaneously measure contractility in a 96 multi-well format. We investigated the effects of GPCR agonists (acetylcholine and carbachol), a Ca2+ channel agonist (S-Bay K8644), an HCN channel antagonist (ivabradine) and K+ channel antagonists (4-AP and vernakalant). We observed differential effects between atrial and ventricular hiPSC-CMs on contractile properties including beat rate, beat duration, contractile force and evidence of arrhythmias at a range of concentrations. As an excerpt of the compound analysis, S-Bay K8644 treatment showed an induced concentration-dependent transient increase in beat duration of atrial hiPSC-CMs, whereas ventricular cells showed a physiological increase in beat rate over time. Carbachol treatment produced marked effects on atrial cells, such as increased beat duration alongside a decrease in beat rate over time, but only minimal effects on ventricular cardiomyocytes. In the context of this chamber-specific pharmacology, we not only add to contractile characterization of hiPSC-CMs but propose a multi-well platform for medium-throughput early compound screening. Overall, these insights illustrate the key pharmacological differences between chamber-specific cardiomyocytes and their application on a multi-well contractility platform to gain insights for in vitro cardiac liability studies and disease modelling.
Collapse
Affiliation(s)
| | - Jan Hunker
- innoVitro GmbH, Artilleriestr 2, 52428 Jülich, Germany
| | - Jamie Bhagwan
- Axol Bioscience Ltd, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Peter Linder
- innoVitro GmbH, Artilleriestr 2, 52428 Jülich, Germany
| | - Ulrich Thomas
- Nanion Technologies GmbH, Ganghoferstr 70A, 80339 Munich, Germany
| | - Hardeep Lotay
- Axol Bioscience Ltd, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Steven Broadbent
- Axol Bioscience Ltd, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Elena Dragicevic
- Nanion Technologies GmbH, Ganghoferstr 70A, 80339 Munich, Germany
| | | | - Jan Turner
- Axol Bioscience Ltd, Babraham Research Campus, Cambridge CB22 3AT, UK
| | | |
Collapse
|
2
|
Averin AS, Konakov MV, Pimenov OY, Galimova MH, Berezhnov AV, Nenov MN, Dynnik VV. Regulation of Papillary Muscle Contractility by NAD and Ammonia Interplay: Contribution of Ion Channels and Exchangers. MEMBRANES 2022; 12:1239. [PMID: 36557146 PMCID: PMC9785361 DOI: 10.3390/membranes12121239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 12/04/2022] [Accepted: 12/04/2022] [Indexed: 06/17/2023]
Abstract
Various models, including stem cells derived and isolated cardiomyocytes with overexpressed channels, are utilized to analyze the functional interplay of diverse ion currents involved in cardiac automaticity and excitation-contraction coupling control. Here, we used β-NAD and ammonia, known hyperpolarizing and depolarizing agents, respectively, and applied inhibitory analysis to reveal the interplay of several ion channels implicated in rat papillary muscle contractility control. We demonstrated that: 4 mM β-NAD, having no strong impact on resting membrane potential (RMP) and action potential duration (APD90) of ventricular cardiomyocytes, evoked significant suppression of isometric force (F) of paced papillary muscle. Reactive blue 2 restored F to control values, suggesting the involvement of P2Y-receptor-dependent signaling in β-NAD effects. Meantime, 5 mM NH4Cl did not show any effect on F of papillary muscle but resulted in significant RMP depolarization, APD90 shortening, and a rightward shift of I-V relationship for total steady state currents in cardiomyocytes. Paradoxically, NH4Cl, being added after β-NAD and having no effect on RMP, APD, and I-V curve, recovered F to the control values, indicating β-NAD/ammonia antagonism. Blocking of HCN, Kir2.x, and L-type calcium channels, Ca2+-activated K+ channels (SK, IK, and BK), or NCX exchanger reverse mode prevented this effect, indicating consistent cooperation of all currents mediated by these channels and NCX. We suggest that the activation of Kir2.x and HCN channels by extracellular K+, that creates positive and negative feedback, and known ammonia and K+ resemblance, may provide conditions required for the activation of all the chain of channels involved in the interplay. Here, we present a mechanistic model describing an interplay of channels and second messengers, which may explain discovered antagonism of β-NAD and ammonia on rat papillary muscle contractile activity.
Collapse
Affiliation(s)
- Alexey S. Averin
- Institute of Theoretical and Experimental Biophysics, the Russian Academy of Sciences, Pushchino 142290, Russia
| | - Maxim V. Konakov
- Institute of Theoretical and Experimental Biophysics, the Russian Academy of Sciences, Pushchino 142290, Russia
| | - Oleg Y. Pimenov
- Institute of Theoretical and Experimental Biophysics, the Russian Academy of Sciences, Pushchino 142290, Russia
| | - Miliausha H. Galimova
- Institute of Theoretical and Experimental Biophysics, the Russian Academy of Sciences, Pushchino 142290, Russia
| | - Alexey V. Berezhnov
- Institute of Cell Biophysics, the Russian Academy of Sciences, Pushchino 142290, Russia
| | - Miroslav N. Nenov
- Institute of Theoretical and Experimental Biophysics, the Russian Academy of Sciences, Pushchino 142290, Russia
| | - Vladimir V. Dynnik
- Institute of Theoretical and Experimental Biophysics, the Russian Academy of Sciences, Pushchino 142290, Russia
| |
Collapse
|
3
|
Kondapuram M, Frieg B, Yüksel S, Schwabe T, Sattler C, Lelle M, Schweinitz A, Schmauder R, Benndorf K, Gohlke H, Kusch J. Functional and structural characterization of interactions between opposite subunits in HCN pacemaker channels. Commun Biol 2022; 5:430. [PMID: 35534535 PMCID: PMC9085832 DOI: 10.1038/s42003-022-03360-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 04/13/2022] [Indexed: 11/13/2022] Open
Abstract
Hyperpolarization-activated and cyclic nucleotide (HCN) modulated channels are tetrameric cation channels. In each of the four subunits, the intracellular cyclic nucleotide-binding domain (CNBD) is coupled to the transmembrane domain via a helical structure, the C-linker. High-resolution channel structures suggest that the C-linker enables functionally relevant interactions with the opposite subunit, which might be critical for coupling the conformational changes in the CNBD to the channel pore. We combined mutagenesis, patch-clamp technique, confocal patch-clamp fluorometry, and molecular dynamics (MD) simulations to show that residue K464 of the C-linker is relevant for stabilizing the closed state of the mHCN2 channel by forming interactions with the opposite subunit. MD simulations revealed that in the K464E channel, a rotation of the intracellular domain relative to the channel pore is induced, which is similar to the cAMP-induced rotation, weakening the autoinhibitory effect of the unoccupied CL-CNBD region. We suggest that this CL-CNBD rotation is considerably involved in activation-induced affinity increase but only indirectly involved in gate modulation. The adopted poses shown herein are in excellent agreement with previous structural results. Interactions between opposite subunits of HCN channels are relevant for stabilizing the auto-inhibited state of the channel. Like cAMP-binding, K464E-mutation breaks these interactions to favor a channel’s pre-activated state.
Collapse
Affiliation(s)
- Mahesh Kondapuram
- Universitätsklinikum Jena, Institut für Physiologie II, Jena, Germany
| | - Benedikt Frieg
- John von Neumann-Institut für Computing (NIC), Jülich Supercomputing Centre (JSC), and Institut für Biologische Informationsprozesse (IBI-7: Strukturbiochemie), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Sezin Yüksel
- Universitätsklinikum Jena, Institut für Physiologie II, Jena, Germany
| | - Tina Schwabe
- Universitätsklinikum Jena, Institut für Physiologie II, Jena, Germany
| | - Christian Sattler
- Universitätsklinikum Jena, Institut für Physiologie II, Jena, Germany
| | - Marco Lelle
- Universitätsklinikum Jena, Institut für Physiologie II, Jena, Germany
| | - Andrea Schweinitz
- Universitätsklinikum Jena, Institut für Physiologie II, Jena, Germany
| | - Ralf Schmauder
- Universitätsklinikum Jena, Institut für Physiologie II, Jena, Germany
| | - Klaus Benndorf
- Universitätsklinikum Jena, Institut für Physiologie II, Jena, Germany
| | - Holger Gohlke
- John von Neumann-Institut für Computing (NIC), Jülich Supercomputing Centre (JSC), and Institut für Biologische Informationsprozesse (IBI-7: Strukturbiochemie), Forschungszentrum Jülich GmbH, Jülich, Germany. .,Institut für Pharmazeutische und Medizinische Chemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany. .,Institut für Bio- und Geowissenschaften (IBG-4: Bioinformatik), Forschungszentrum Jülich GmbH, Jülich, Germany.
| | - Jana Kusch
- Universitätsklinikum Jena, Institut für Physiologie II, Jena, Germany.
| |
Collapse
|
4
|
Oknińska M, Paterek A, Zambrowska Z, Mackiewicz U, Mączewski M. Effect of Ivabradine on Cardiac Ventricular Arrhythmias: Friend or Foe? J Clin Med 2021; 10:4732. [PMID: 34682854 PMCID: PMC8537674 DOI: 10.3390/jcm10204732] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/24/2021] [Accepted: 10/08/2021] [Indexed: 12/12/2022] Open
Abstract
Life-threatening ventricular arrhythmias, such as ventricular tachycardia and ventricular fibrillation remain an ongoing clinical problem and their prevention and treatment require optimization. Conventional antiarrhythmic drugs are associated with significant proarrhythmic effects that often outweigh their benefits. Another option, the implantable cardioverter defibrillator, though clearly the primary therapy for patients at high risk of ventricular arrhythmias, is costly, invasive, and requires regular monitoring. Thus there is a clear need for new antiarrhythmic treatment strategies. Ivabradine, a heartrate-reducing agent, an inhibitor of HCN channels, may be one of such options. In this review we discuss emerging data from experimental studies that indicate new mechanism of action of this drug and further areas of investigation and potential use of ivabradine as an antiarrhythmic agent. However, clinical evidence is limited, and the jury is still out on effects of ivabradine on cardiac ventricular arrhythmias in the clinical setting.
Collapse
Affiliation(s)
| | | | | | | | - Michał Mączewski
- Centre of Postgraduate Medical Education, Department of Clinical Physiology, ul. Marymoncka 99/103, 01-813 Warsaw, Poland; (M.O.); (A.P.); (Z.Z.); (U.M.)
| |
Collapse
|
5
|
Hadova K, Kralova E, Doka G, Bies Pivackova L, Kmecova Z, Krenek P, Klimas J. Isolated downregulation of HCN2 in ventricles of rats with streptozotocin-induced diabetic cardiomyopathy. BMC Cardiovasc Disord 2021; 21:118. [PMID: 33653265 PMCID: PMC7927235 DOI: 10.1186/s12872-021-01929-3] [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: 11/05/2020] [Accepted: 02/11/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In spite of disrupted repolarization of diabetic heart, some studies report less tendency of diabetic heart to develop ventricular arrhythmias suggesting effective compensatory mechanism. We hypothesized that myocardial alterations in HCN2 and HCN4 channels occur under hyperglycaemia. METHODS Diabetes was induced in rats using a single injection of streptozotocin (STZ; 55 mg/kg body weight, i.p.). Basal ECG was measured. Expression of mRNA for HCN channels, potassium channels and microRNA 1 and 133a were measured in ventricular tissues. Protein expression of HCN2 channel isoform was assessed in five different regions of the heart by western blotting. Differentiated H9c2 cell line was used to examine HCN channels expression under hyperglycaemia in vitro. RESULTS Six weeks after STZ administration, heart rate was reduced, QRS complex duration, QT interval and T-wave were prolonged in diabetic rats compared to controls. mRNA and protein expressions of HCN2 decreased exclusively in the ventricles of diabetic rats. HCN2 expression levels in atria of STZ rats and H9c2 cells treated with excess of glucose were not changed. MicroRNA levels were stable in STZ rat hearts. We found significantly decreased mRNA levels of several potassium channels participating in repolarization, namely Kcnd2 (Ito1), Kcnh2 (IKr), Kcnq1 (IKs) and Kcnj11 (IKATP). CONCLUSIONS This result together with downregulated HCN2 channels suggest that HCN channels might be an integral part of ventricular electric remodelling and might play a role in cardiac repolarization projected in altered arrhythmogenic profile of diabetic heart.
Collapse
Affiliation(s)
- Katarina Hadova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University in Bratislava, Odbojarov 10, 832 32, Bratislava, Slovakia
| | - Eva Kralova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University in Bratislava, Odbojarov 10, 832 32, Bratislava, Slovakia
| | - Gabriel Doka
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University in Bratislava, Odbojarov 10, 832 32, Bratislava, Slovakia
| | - Lenka Bies Pivackova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University in Bratislava, Odbojarov 10, 832 32, Bratislava, Slovakia
| | - Zuzana Kmecova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University in Bratislava, Odbojarov 10, 832 32, Bratislava, Slovakia
| | - Peter Krenek
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University in Bratislava, Odbojarov 10, 832 32, Bratislava, Slovakia
| | - Jan Klimas
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Comenius University in Bratislava, Odbojarov 10, 832 32, Bratislava, Slovakia.
| |
Collapse
|
6
|
Chakraborty P, Rose RA, Nair K, Downar E, Nanthakumar K. The rationale for repurposing funny current inhibition for management of ventricular arrhythmia. Heart Rhythm 2020; 18:130-137. [PMID: 32738405 DOI: 10.1016/j.hrthm.2020.07.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 07/14/2020] [Accepted: 07/25/2020] [Indexed: 11/26/2022]
Abstract
Management of ventricular arrhythmia in structural heart disease is complicated by the toxicity of the limited antiarrhythmic options available. In others, proarrhythmia and deleterious hemodynamic and noncardiac effects prevent practical use. This necessitates new thinking in therapeutic agents for ventricular arrhythmia in structural heart disease. Ivabradine, a funny current (If) inhibitor, has proven safety in heart failure, angina, and inappropriate sinus tachycardia. Although it is commonly known that funny channels are primarily expressed in the sinoatrial node, atrioventricular node, and conducting system of the ventricle, ivabradine is known to exert effects on metabolism, ion homeostasis, and membrane electrophysiology of remodeled ventricular myocardium. This review considers novel concepts and evidence from clinical and experimental studies regarding this paradigm, with a potential role of ivabradine in ventricular arrhythmia.
Collapse
Affiliation(s)
- Praloy Chakraborty
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada; University Health Network, Toronto, Ontario, Canada
| | - Robert A Rose
- Libin Cardiovascular Institute of Alberta, An entity of the University of Calgary and Alberta Health Services, Calgary, Alberta, Canada
| | - Krishnakumar Nair
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada; University Health Network, Toronto, Ontario, Canada
| | - Eugene Downar
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada; University Health Network, Toronto, Ontario, Canada
| | - Kumaraswamy Nanthakumar
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada; University Health Network, Toronto, Ontario, Canada.
| |
Collapse
|
7
|
Ziyatdinova NI, Kuptsova AM, Faskhutdinov LI, Galieva AM, Zefirov AL, Zefirov TL. Effect of If Current Blockade on Newborn Rat Heart Isolated According to Langendorff. Bull Exp Biol Med 2019; 167:424-427. [PMID: 31529169 DOI: 10.1007/s10517-019-04541-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Indexed: 01/09/2023]
Abstract
The study examined the effects of hyperpolarization-activated funny current (If) on HR and coronary flow in Langendorff-isolated hearts from newborn rats. Blockade of If current with ZD7288 changed the examined cardiac parameters. The blocker in a concentration of 10-9 M decreased HR by 26.8% (p≤0.05). In concentrations 10-8, 10-7, 10-6, and 10-5 M ZD7288 produced minor differently directed effects. In a concentration of 10-5 M, ZD7288 reduced coronary flow in the isolated heart (p≤0.01). In other concentrations, the blocker produced no significant effects on coronary flow.
Collapse
Affiliation(s)
- N I Ziyatdinova
- Department of Human Health Protection, Kazan (Volga region) Federal University, Kazan, Russia
| | - A M Kuptsova
- Department of Human Health Protection, Kazan (Volga region) Federal University, Kazan, Russia
| | - L I Faskhutdinov
- Department of Human Health Protection, Kazan (Volga region) Federal University, Kazan, Russia
| | - A M Galieva
- Department of Human Health Protection, Kazan (Volga region) Federal University, Kazan, Russia
| | - A L Zefirov
- Department of Normal Physiology, Kazan Federal Medical University, Kazan, the republic of Tatarstan, Russia
| | - T L Zefirov
- Department of Human Health Protection, Kazan (Volga region) Federal University, Kazan, Russia.
| |
Collapse
|
8
|
Silbernagel N, Walecki M, Schäfer MKH, Kessler M, Zobeiri M, Rinné S, Kiper AK, Komadowski MA, Vowinkel KS, Wemhöner K, Fortmüller L, Schewe M, Dolga AM, Scekic-Zahirovic J, Matschke LA, Culmsee C, Baukrowitz T, Monassier L, Ullrich ND, Dupuis L, Just S, Budde T, Fabritz L, Decher N. The VAMP-associated protein VAPB is required for cardiac and neuronal pacemaker channel function. FASEB J 2018; 32:6159-6173. [PMID: 29879376 PMCID: PMC6629115 DOI: 10.1096/fj.201800246r] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels encode neuronal and cardiac pacemaker currents. The composition of pacemaker channel complexes in different tissues is poorly understood, and the presence of additional HCN modulating subunits was speculated. Here we show that vesicle-associated membrane protein-associated protein B (VAPB), previously associated with a familial form of amyotrophic lateral sclerosis 8, is an essential HCN1 and HCN2 modulator. VAPB significantly increases HCN2 currents and surface expression and has a major influence on the dendritic neuronal distribution of HCN2. Severe cardiac bradycardias in VAPB-deficient zebrafish and VAPB-/- mice highlight that VAPB physiologically serves to increase cardiac pacemaker currents. An altered T-wave morphology observed in the ECGs of VAPB-/- mice supports the recently proposed role of HCN channels for ventricular repolarization. The critical function of VAPB in native pacemaker channel complexes will be relevant for our understanding of cardiac arrhythmias and epilepsies, and provides an unexpected link between these diseases and amyotrophic lateral sclerosis.-Silbernagel, N., Walecki, M., Schäfer, M.-K. H., Kessler, M., Zobeiri, M., Rinné, S., Kiper, A. K., Komadowski, M. A., Vowinkel, K. S., Wemhöner, K., Fortmüller, L., Schewe, M., Dolga, A. M., Scekic-Zahirovic, J., Matschke, L. A., Culmsee, C., Baukrowitz, T., Monassier, L., Ullrich, N. D., Dupuis, L., Just, S., Budde, T., Fabritz, L., Decher, N. The VAMP-associated protein VAPB is required for cardiac and neuronal pacemaker channel function.
Collapse
Affiliation(s)
- Nicole Silbernagel
- Institute of Physiology and Pathophysiology, Vegetative Physiology, Phillips University, Marburg, Germany
| | - Magdalena Walecki
- Institute of Physiology and Pathophysiology, Vegetative Physiology, Phillips University, Marburg, Germany
| | - Martin K-H Schäfer
- Institute of Anatomy and Cell Biology, Philipps University, Marburg, Germany
| | - Mirjam Kessler
- Molecular Cardiology, Department of Internal Medicine II, University Hospital Ulm, Ulm, Germany
| | | | - Susanne Rinné
- Institute of Physiology and Pathophysiology, Vegetative Physiology, Phillips University, Marburg, Germany
| | - Aytug K Kiper
- Institute of Physiology and Pathophysiology, Vegetative Physiology, Phillips University, Marburg, Germany
| | - Marlene A Komadowski
- Institute of Physiology and Pathophysiology, Vegetative Physiology, Phillips University, Marburg, Germany.,Institute of Anatomy and Cell Biology, Philipps University, Marburg, Germany
| | - Kirsty S Vowinkel
- Institute of Physiology and Pathophysiology, Vegetative Physiology, Phillips University, Marburg, Germany
| | - Konstantin Wemhöner
- Institute of Physiology and Pathophysiology, Vegetative Physiology, Phillips University, Marburg, Germany
| | - Lisa Fortmüller
- Department of Cardiology II - Electrophysiology, University Hospital Münster, University of Münster, Munster, Germany
| | - Marcus Schewe
- Institute of Physiology, Christian-Albrechts University, Kiel, Germany
| | - Amalia M Dolga
- Institute of Pharmacology and Clinical Pharmacy, Phillips University, Marburg, Germany
| | - Jelena Scekic-Zahirovic
- Laboratoire de Pharmacologie et Toxicologie NeuroCardiovasculaire, Faculté de Médecine, Université de Strasbourg, Strasbourg, France
| | - Lina A Matschke
- Institute of Physiology and Pathophysiology, Vegetative Physiology, Phillips University, Marburg, Germany
| | - Carsten Culmsee
- Institute of Pharmacology and Clinical Pharmacy, Phillips University, Marburg, Germany
| | - Thomas Baukrowitz
- Institute of Physiology, Christian-Albrechts University, Kiel, Germany
| | - Laurent Monassier
- Laboratoire de Pharmacologie et Toxicologie NeuroCardiovasculaire, Faculté de Médecine, Université de Strasbourg, Strasbourg, France
| | - Nina D Ullrich
- Institute of Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany
| | - Luc Dupuis
- Laboratoire de Neurobiologie et Pharmacologie Cardiovasculaire, Faculté de Médecine, Université de Strasbourg, Strasbourg, France.,INSERM, Faculté de Médecine, Université de Strasbourg, Strasbourg, France
| | - Steffen Just
- Molecular Cardiology, Department of Internal Medicine II, University Hospital Ulm, Ulm, Germany
| | - Thomas Budde
- Institute for Physiology I, University of Münster, Munster, Germany
| | - Larissa Fabritz
- Department of Cardiology II - Electrophysiology, University Hospital Münster, University of Münster, Munster, Germany.,Institute of Cardiovascular Sciences, University Hospital Birmingham, University of Birmingham, Birmingham, United Kingdom.,Department of Cardiology, University Hospital Birmingham, University of Birmingham, Birmingham, United Kingdom.,Division of Rhythmology, Department of Genetic Epidemiology, University Hospital Münster, University of Münster, Munster, Germany.,Institute of Human Genetics, Department of Genetic Epidemiology, University Hospital Münster, University of Münster, Munster, Germany
| | - Niels Decher
- Institute of Physiology and Pathophysiology, Vegetative Physiology, Phillips University, Marburg, Germany
| |
Collapse
|
9
|
Abstract
The Popeye domain containing (POPDC) genes encode transmembrane proteins, which are abundantly expressed in striated muscle cells. Hallmarks of the POPDC proteins are the presence of three transmembrane domains and the Popeye domain, which makes up a large part of the cytoplasmic portion of the protein and functions as a cAMP-binding domain. Interestingly, despite the prediction of structural similarity between the Popeye domain and other cAMP binding domains, at the protein sequence level they strongly differ from each other suggesting an independent evolutionary origin of POPDC proteins. Loss-of-function experiments in zebrafish and mouse established an important role of POPDC proteins for cardiac conduction and heart rate adaptation after stress. Loss-of function mutations in patients have been associated with limb-girdle muscular dystrophy and AV-block. These data suggest an important role of these proteins in the maintenance of structure and function of striated muscle cells.
Collapse
|
10
|
Novella Romanelli M, Sartiani L, Masi A, Mannaioni G, Manetti D, Mugelli A, Cerbai E. HCN Channels Modulators: The Need for Selectivity. Curr Top Med Chem 2016; 16:1764-91. [PMID: 26975509 PMCID: PMC5374843 DOI: 10.2174/1568026616999160315130832] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 08/04/2015] [Accepted: 08/05/2015] [Indexed: 12/27/2022]
Abstract
Hyperpolarization-activated, cyclic nucleotide-gated (HCN) channels, the molecular correlate of the hyperpolarization-activated current (If/Ih), are membrane proteins which play an important role in several physiological processes and various pathological conditions. In the Sino Atrial Node (SAN) HCN4 is the target of ivabradine, a bradycardic agent that is, at the moment, the only drug which specifically blocks If. Nevertheless, several other pharmacological agents have been shown to modulate HCN channels, a property that may contribute to their therapeutic activity and/or to their side effects. HCN channels are considered potential targets for developing drugs to treat several important pathologies, but a major issue in this field is the discovery of isoform-selective compounds, owing to the wide distribution of these proteins into the central and peripheral nervous systems, heart and other peripheral tissues. This survey is focused on the compounds that have been shown, or have been designed, to interact with HCN channels and on their binding sites, with the aim to summarize current knowledge and possibly to unveil useful information to design new potent and selective modulators.
Collapse
Affiliation(s)
- Maria Novella Romanelli
- University of Florence, Department of Neurosciences, Psychology, Drug Research and Child's Health, Section of Pharmaceutical and Nutraceutical Sciences, via Ugo Schiff 6, 50019 Sesto Fiorentino, Italy.
| | | | | | | | | | | | | |
Collapse
|
11
|
Herrmann S, Schnorr S, Ludwig A. HCN channels--modulators of cardiac and neuronal excitability. Int J Mol Sci 2015; 16:1429-47. [PMID: 25580535 PMCID: PMC4307311 DOI: 10.3390/ijms16011429] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 12/31/2014] [Indexed: 01/06/2023] Open
Abstract
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels comprise a family of cation channels activated by hyperpolarized membrane potentials and stimulated by intracellular cyclic nucleotides. The four members of this family, HCN1-4, show distinct biophysical properties which are most evident in the kinetics of activation and deactivation, the sensitivity towards cyclic nucleotides and the modulation by tyrosine phosphorylation. The four isoforms are differentially expressed in various excitable tissues. This review will mainly focus on recent insights into the functional role of the channels apart from their classic role as pacemakers. The importance of HCN channels in the cardiac ventricle and ventricular hypertrophy will be discussed. In addition, their functional significance in the peripheral nervous system and nociception will be examined. The data, which are mainly derived from studies using transgenic mice, suggest that HCN channels contribute significantly to cellular excitability in these tissues. Remarkably, the impact of the channels is clearly more pronounced in pathophysiological states including ventricular hypertrophy as well as neural inflammation and neuropathy suggesting that HCN channels may constitute promising drug targets in the treatment of these conditions. This perspective as well as the current therapeutic use of HCN blockers will also be addressed.
Collapse
Affiliation(s)
- Stefan Herrmann
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany.
| | - Sabine Schnorr
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany.
| | - Andreas Ludwig
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany.
| |
Collapse
|
12
|
Zhou YF, Yang XJ, Li HX, Han LH, Jiang WP. Genetically-engineered mesenchymal stem cells transfected with human HCN1 gene to create cardiac pacemaker cells. J Int Med Res 2014; 41:1570-6. [PMID: 24097828 DOI: 10.1177/0300060513501123] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVE To test the proof-of-principle that genetically-engineered mesenchymal stem cells (MSCs) transfected with the human hyperpolarization-activated cyclic nucleotide-gated channel 1 (hHCN1) gene can be modified to become cardiac pacemaker cells. METHODS MSCs were transfected with the hHCN1 gene using lentiviral-based transfection. The expressed pacemaker current (I(f)) in hHCN1-transfected MSCs was recorded using whole-cell patch-clamp analysis. The effect of the hHCN1-transfected MSCs on cardiomyocyte excitability was determined by coculturing the MSCs with neonatal rabbit ventricular myocytes (NRVM). The spontaneous action potentials of the NRVM were recorded by whole-cell current-clamp analysis. RESULTS A high level time- and voltage-dependent inward hyperpolarization current that was inhibited by 4 mM caesium chloride was detected in hHCN1-transfected MSCs, suggesting that the HCN1 proteins acted as I(f) channels in MSCs. The mean ± SE beating frequency in NRVMs cocultured with control MSCs transfected with the pcDNA3 plasmid control was 82 ± 8 beats/min (n = 5) compared with 129 ± 11 beats/min (n = 5) in NRVMs cocultured with hHCN1-transfected MSCs. CONCLUSIONS Genetically-engineered MSCs transfected with the hHCN1 gene can be modified to become cardiac pacemaker cells.
Collapse
Affiliation(s)
- Ya-Feng Zhou
- Department of Cardiology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China
| | | | | | | | | |
Collapse
|
13
|
Wahl-Schott C, Fenske S, Biel M. HCN channels: new roles in sinoatrial node function. Curr Opin Pharmacol 2014; 15:83-90. [DOI: 10.1016/j.coph.2013.12.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 12/16/2013] [Accepted: 12/17/2013] [Indexed: 11/25/2022]
|
14
|
Powell KL, Jones NC, Kennard JT, Ng C, Urmaliya V, Lau S, Tran A, Zheng T, Ozturk E, Dezsi G, Megatia I, Delbridge LM, Pinault D, Reid CA, White PJ, O'Brien TJ. HCN channelopathy and cardiac electrophysiologic dysfunction in genetic and acquired rat epilepsy models. Epilepsia 2014; 55:609-20. [PMID: 24592881 DOI: 10.1111/epi.12563] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/13/2014] [Indexed: 01/20/2023]
Abstract
OBJECTIVE Evidence from animal and human studies indicates that epilepsy can affect cardiac function, although the molecular basis of this remains poorly understood. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels generate pacemaker activity and modulate cellular excitability in the brain and heart, with altered expression and function associated with epilepsy and cardiomyopathies. Whether HCN expression is altered in the heart in association with epilepsy has not been investigated previously. We studied cardiac electrophysiologic properties and HCN channel subunit expression in rat models of genetic generalized epilepsy (Genetic Absence Epilepsy Rats from Strasbourg, GAERS) and acquired temporal lobe epilepsy (post-status epilepticus SE). We hypothesized that the development of epilepsy is associated with altered cardiac electrophysiologic function and altered cardiac HCN channel expression. METHODS Electrocardiography studies were recorded in vivo in rats and in vitro in isolated hearts. Cardiac HCN channel messenger RNA (mRNA) and protein expression were measured using quantitative PCR and Western blotting respectively. RESULTS Cardiac electrophysiology was significantly altered in adult GAERS, with slower heart rate, shorter QRS duration, longer QTc interval, and greater standard deviation of RR intervals compared to control rats. In the post-SE model, we observed similar interictal changes in several of these parameters, and we also observed consistent and striking bradycardia associated with the onset of ictal activity. Molecular analysis demonstrated significant reductions in cardiac HCN2 mRNA and protein expression in both models, providing a molecular correlate of these electrophysiologic abnormalities. SIGNIFICANCE These results demonstrate that ion channelopathies and cardiac dysfunction can develop as a secondary consequence of chronic epilepsy, which may have relevance for the pathophysiology of cardiac dysfunction in patients with epilepsy.
Collapse
Affiliation(s)
- Kim L Powell
- Department of Medicine, The Royal Melbourne Hospital, The University of Melbourne, Parkville, Victoria, Australia
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Ramirez JM. The integrative role of the sigh in psychology, physiology, pathology, and neurobiology. PROGRESS IN BRAIN RESEARCH 2014; 209:91-129. [PMID: 24746045 DOI: 10.1016/b978-0-444-63274-6.00006-0] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
"Sighs, tears, grief, distress" expresses Johann Sebastian Bach in a musical example for the relationship between sighs and deep emotions. This review explores the neurobiological basis of the sigh and its relationship with psychology, physiology, and pathology. Sighs monitor changes in brain states, induce arousal, and reset breathing variability. These behavioral roles homeostatically regulate breathing stability under physiological and pathological conditions. Sighs evoked in hypoxia evoke arousal and thereby become critical for survival. Hypoarousal and failure to sigh have been associated with sudden infant death syndrome. Increased breathing irregularity may provoke excessive sighing and hyperarousal, a behavioral sequence that may play a role in panic disorders. Essential for generating sighs and breathing is the pre-Bötzinger complex. Modulatory and synaptic interactions within this local network and between networks located in the brainstem, cerebellum, cortex, hypothalamus, amygdala, and the periaqueductal gray may govern the relationships between physiology, psychology, and pathology. Unraveling these circuits will lead to a better understanding of how we balance emotions and how emotions become pathological.
Collapse
Affiliation(s)
- Jan-Marino Ramirez
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA; Department of Neurological Surgery, University of Washington, Seattle, WA, USA.
| |
Collapse
|
16
|
Kuwabara Y, Kuwahara K, Takano M, Kinoshita H, Arai Y, Yasuno S, Nakagawa Y, Igata S, Usami S, Minami T, Yamada Y, Nakao K, Yamada C, Shibata J, Nishikimi T, Ueshima K, Nakao K. Increased expression of HCN channels in the ventricular myocardium contributes to enhanced arrhythmicity in mouse failing hearts. J Am Heart Assoc 2013; 2:e000150. [PMID: 23709563 PMCID: PMC3698776 DOI: 10.1161/jaha.113.000150] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 04/30/2013] [Indexed: 01/08/2023]
Abstract
BACKGROUND The efficacy of pharmacological interventions to prevent sudden arrhythmic death in patients with chronic heart failure remains limited. Evidence now suggests increased ventricular expression of hyperpolarization-activated cation (HCN) channels in hypertrophied and failing hearts contributes to their arrythmicity. Still, the role of induced HCN channel expression in the enhanced arrhythmicity associated with heart failure and the capacity of HCN channel blockade to prevent lethal arrhythmias remains undetermined. METHODS AND RESULTS We examined the effects of ivabradine, a specific HCN channel blocker, on survival and arrhythmicity in transgenic mice (dnNRSF-Tg) expressing a cardiac-specific dominant-negative form of neuron-restrictive silencer factor, a useful mouse model of dilated cardiomyopathy leading to sudden death. Ivabradine (7 mg/kg per day orally) significantly reduced ventricular tachyarrhythmias and improved survival among dnNRSF-Tg mice while having no significant effect on heart rate or cardiac structure or function. Ivabradine most likely prevented the increase in automaticity otherwise seen in dnNRSF-Tg ventricular myocytes. Moreover, cardiac-specific overexpression of HCN2 in mice (HCN2-Tg) made hearts highly susceptible to arrhythmias induced by chronic β-adrenergic stimulation. Indeed, ventricular myocytes isolated from HCN2-Tg mice were highly susceptible to β-adrenergic stimulation-induced abnormal automaticity, which was inhibited by ivabradine. CONCLUSIONS HCN channel blockade by ivabradine reduces lethal arrhythmias associated with dilated cardiomyopathy in mice. Conversely, cardiac-specific overexpression of HCN2 channels increases arrhythmogenicity of β-adrenergic stimulation. Our findings demonstrate the contribution of HCN channels to the increased arrhythmicity seen in failing hearts and suggest HCN channel blockade is a potentially useful approach to preventing sudden death in patients with heart failure.
Collapse
Affiliation(s)
- Yoshihiro Kuwabara
- Department of Medicine and Clinical Science, Kyoto University Graduate School of Medicine, Kyoto, Japan (Y.K., K.K., H.K., Y.N., S.U., T.M., Y.Y., K.N., C.Y., J.S., T.N., K.N.)
| | - Koichiro Kuwahara
- Department of Medicine and Clinical Science, Kyoto University Graduate School of Medicine, Kyoto, Japan (Y.K., K.K., H.K., Y.N., S.U., T.M., Y.Y., K.N., C.Y., J.S., T.N., K.N.)
| | - Makoto Takano
- Department of Physiology, Kurume University School of Medicine, Japan (M.T., S.I.)
| | - Hideyuki Kinoshita
- Department of Medicine and Clinical Science, Kyoto University Graduate School of Medicine, Kyoto, Japan (Y.K., K.K., H.K., Y.N., S.U., T.M., Y.Y., K.N., C.Y., J.S., T.N., K.N.)
| | - Yuji Arai
- Department of Bioscience, National Cerebral and Cardiovascular Center Research Institute, Japan (Y.A.)
| | - Shinji Yasuno
- EBM Research Center, Kyoto University Graduate School of Medicine, Kyoto, Japan (S.Y., K.U.)
| | - Yasuaki Nakagawa
- Department of Medicine and Clinical Science, Kyoto University Graduate School of Medicine, Kyoto, Japan (Y.K., K.K., H.K., Y.N., S.U., T.M., Y.Y., K.N., C.Y., J.S., T.N., K.N.)
| | - Sachiyo Igata
- Department of Physiology, Kurume University School of Medicine, Japan (M.T., S.I.)
| | - Satoru Usami
- Department of Medicine and Clinical Science, Kyoto University Graduate School of Medicine, Kyoto, Japan (Y.K., K.K., H.K., Y.N., S.U., T.M., Y.Y., K.N., C.Y., J.S., T.N., K.N.)
| | - Takeya Minami
- Department of Medicine and Clinical Science, Kyoto University Graduate School of Medicine, Kyoto, Japan (Y.K., K.K., H.K., Y.N., S.U., T.M., Y.Y., K.N., C.Y., J.S., T.N., K.N.)
| | - Yuko Yamada
- Department of Medicine and Clinical Science, Kyoto University Graduate School of Medicine, Kyoto, Japan (Y.K., K.K., H.K., Y.N., S.U., T.M., Y.Y., K.N., C.Y., J.S., T.N., K.N.)
| | - Kazuhiro Nakao
- Department of Medicine and Clinical Science, Kyoto University Graduate School of Medicine, Kyoto, Japan (Y.K., K.K., H.K., Y.N., S.U., T.M., Y.Y., K.N., C.Y., J.S., T.N., K.N.)
| | - Chinatsu Yamada
- Department of Medicine and Clinical Science, Kyoto University Graduate School of Medicine, Kyoto, Japan (Y.K., K.K., H.K., Y.N., S.U., T.M., Y.Y., K.N., C.Y., J.S., T.N., K.N.)
| | - Junko Shibata
- Department of Medicine and Clinical Science, Kyoto University Graduate School of Medicine, Kyoto, Japan (Y.K., K.K., H.K., Y.N., S.U., T.M., Y.Y., K.N., C.Y., J.S., T.N., K.N.)
| | - Toshio Nishikimi
- Department of Medicine and Clinical Science, Kyoto University Graduate School of Medicine, Kyoto, Japan (Y.K., K.K., H.K., Y.N., S.U., T.M., Y.Y., K.N., C.Y., J.S., T.N., K.N.)
| | - Kenji Ueshima
- EBM Research Center, Kyoto University Graduate School of Medicine, Kyoto, Japan (S.Y., K.U.)
| | - Kazuwa Nakao
- Department of Medicine and Clinical Science, Kyoto University Graduate School of Medicine, Kyoto, Japan (Y.K., K.K., H.K., Y.N., S.U., T.M., Y.Y., K.N., C.Y., J.S., T.N., K.N.)
| |
Collapse
|