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Tan YQ, Zhang W, Xie ZC, Li J, Chen HW. CaMK II in Cardiovascular Diseases, Especially CaMK II-δ: Friends or Enemies. Drug Des Devel Ther 2024; 18:3461-3476. [PMID: 39132626 PMCID: PMC11314529 DOI: 10.2147/dddt.s473251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Accepted: 07/05/2024] [Indexed: 08/13/2024] Open
Abstract
Cardiovascular diseases (CVDs) tend to affect the young population and are associated with a significant economic burden and psychological distress to the society and families. The physiological and pathological processes underlying CVDs are complex. Ca2+/calmodulin-dependent kinase II (CaMK II), a protein kinase, has multiple biological functions. It participates in multiple pathological processes and plays a central role in the development of CVDs. Based on this, this paper analyzes the structural characteristics and distribution of CaMK II, the mechanism of action of CaMK II, and the relationship between CaMK II and CVDs, including ion channels, ischemia-reperfusion injury, arrhythmias, myocardial hypertrophy, cardiotoxicity, hypertension, and dilated cardiomyopathy. Given the different regulatory mechanisms of different isoforms of CaMK II, the clinical use of specific targeted inhibitors or novel compounds should be evaluated in future research to provide new directions.
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Affiliation(s)
- Yu-Qing Tan
- Department of Cardiology, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, People’s Republic of China
| | - Wang Zhang
- Department of Pharmacy, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, People’s Republic of China
| | - Zi-Cong Xie
- Department of Cardiology, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, People’s Republic of China
| | - Jun Li
- Department of Cardiology, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, People’s Republic of China
| | - Heng-Wen Chen
- New Drug Research and Development Office, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, People’s Republic of China
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Trum M, Riechel J, Schollmeier E, Lebek S, Hegner P, Reuthner K, Heers S, Keller K, Wester M, Klatt S, Hamdani N, Provaznik Z, Schmid C, Maier L, Arzt M, Wagner S. Empagliflozin inhibits increased Na influx in atrial cardiomyocytes of patients with HFpEF. Cardiovasc Res 2024; 120:999-1010. [PMID: 38728438 PMCID: PMC11288740 DOI: 10.1093/cvr/cvae095] [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] [Received: 12/08/2023] [Revised: 01/16/2024] [Accepted: 02/02/2024] [Indexed: 05/12/2024] Open
Abstract
AIMS Heart failure with preserved ejection fraction (HFpEF) causes substantial morbidity and mortality. Importantly, atrial remodelling and atrial fibrillation are frequently observed in HFpEF. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have recently been shown to improve clinical outcomes in HFpEF, and post-hoc analyses suggest atrial anti-arrhythmic effects. We tested if isolated human atrial cardiomyocytes from patients with HFpEF exhibit an increased Na influx, which is known to cause atrial arrhythmias, and if that is responsive to treatment with the SGTL2i empagliflozin. METHODS AND RESULTS Cardiomyocytes were isolated from atrial biopsies of 124 patients (82 with HFpEF) undergoing elective cardiac surgery. Na influx was measured with the Na-dye Asante Natrium Green-2 AM (ANG-2). Compared to patients without heart failure (NF), Na influx was doubled in HFpEF patients (NF vs. HFpEF: 0.21 ± 0.02 vs. 0.38 ± 0.04 mmol/L/min (N = 7 vs. 18); P = 0.0078). Moreover, late INa (measured via whole-cell patch clamp) was significantly increased in HFpEF compared to NF. Western blot and HDAC4 pulldown assay indicated a significant increase in CaMKII expression, CaMKII autophosphorylation, CaMKII activity, and CaMKII-dependent NaV1.5 phosphorylation in HFpEF compared to NF, whereas NaV1.5 protein and mRNA abundance remained unchanged. Consistently, increased Na influx was significantly reduced by treatment not only with the CaMKII inhibitor autocamtide-2-related inhibitory peptide (AIP), late INa inhibitor tetrodotoxin (TTX) but also with sodium/hydrogen exchanger 1 (NHE1) inhibitor cariporide. Importantly, empagliflozin abolished both increased Na influx and late INa in HFpEF. Multivariate linear regression analysis, adjusting for important clinical confounders, revealed HFpEF to be an independent predictor for changes in Na handling in atrial cardiomyocytes. CONCLUSION We show for the first time increased Na influx in human atrial cardiomyocytes from HFpEF patients, partly due to increased late INa and enhanced NHE1-mediated Na influx. Empagliflozin inhibits Na influx and late INa, which could contribute to anti-arrhythmic effects in patients with HFpEF.
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Affiliation(s)
- Maximilian Trum
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Johannes Riechel
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Elisa Schollmeier
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Simon Lebek
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Philipp Hegner
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Kathrin Reuthner
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Silvia Heers
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Karoline Keller
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Michael Wester
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Susanne Klatt
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Nazha Hamdani
- Department of Cellular and Translational Physiology, Ruhr-University Bochum, Bochum, Germany
| | - Zdenek Provaznik
- Department of Cardiothoracic Surgery, University Hospital Regensburg, Regensburg, Germany
| | - Christof Schmid
- Department of Cardiothoracic Surgery, University Hospital Regensburg, Regensburg, Germany
| | - Lars Maier
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Michael Arzt
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Stefan Wagner
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
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Gissibl T, Stengel L, Tarnowski D, Maier LS, Wagner S, Feder AL, Sag CM. The inotropic and arrhythmogenic effects of acutely increased late I Na are associated with elevated ROS but not oxidation of PKARIα. Front Cardiovasc Med 2024; 11:1379930. [PMID: 39077112 PMCID: PMC11284163 DOI: 10.3389/fcvm.2024.1379930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 06/10/2024] [Indexed: 07/31/2024] Open
Abstract
Background Acute stimulation of the late sodium current (INaL) as pharmacologically induced by Anemonia toxin II (ATX-II) results in Na+-dependent Ca2+ overload and enhanced formation of reactive oxygen species (ROS). This is accompanied by an acute increase in the amplitude of the systolic Ca2+ transient. Ca2+ transient amplitude is determined by L-type Ca2+-mediated transsarcolemmal Ca2+ influx (ICa) into the cytosol and by systolic Ca2+ release from the sarcoplasmic reticulum (SR). Type-1 protein kinase A (PKARIα) becomes activated upon increased ROS and is capable of stimulating ICa, thereby sustaining the amplitude of the systolic Ca2+ transient upon oxidative stress. Objectives We aimed to investigate whether the increase of the systolic Ca2+ transient as acutely induced by INaL (by ATX-II) may involve stimulation of ICa through oxidized PKARIα. Methods We used a transgenic mouse model in which PKARIα was made resistant to oxidative activation by homozygous knock-in replacement of redox-sensitive Cysteine 17 with Serine within the regulatory subunits of PKARIα (KI). ATX-II (at 1 nmol/L) was used to acutely enhance INaL in freshly isolated ventricular myocytes from KI and wild-type (WT) control mice. Epifluorescence and confocal imaging were used to assess intracellular Ca2+ handling and ROS formation. A ruptured-patch whole-cell voltage-clamp was used to measure INaL and ICa. The impact of acutely enhanced INaL on RIα dimer formation and PKA target structures was studied using Western blot analysis. Results ATX-II increased INaL to a similar extent in KI and WT cells, which was associated with significant cytosolic and mitochondrial ROS formation in both genotypes. Acutely activated Ca2+ handling in terms of increased Ca2+ transient amplitudes and elevated SR Ca2+ load was equally present in KI and WT cells. Likewise, cellular arrhythmias as approximated by non-triggered Ca2+ elevations during Ca2+ transient decay and by diastolic SR Ca2+-spark frequency occurred in a comparable manner in both genotypes. Most importantly and in contrast to our initial hypothesis, ATX-II did not alter the magnitude or inactivation kinetics of ICa in neither WT nor KI cells and did not result in PKARIα dimerization (i.e., oxidation) despite a clear prooxidant intracellular environment. Conclusions The inotropic and arrhythmogenic effects of acutely increased INaL are associated with elevated ROS, but do not involve oxidation of PKARIα.
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Hartmann N, Knierim M, Maurer W, Dybkova N, Zeman F, Hasenfuß G, Sossalla S, Streckfuss-Bömeke K. Na V1.8 as Proarrhythmic Target in a Ventricular Cardiac Stem Cell Model. Int J Mol Sci 2024; 25:6144. [PMID: 38892333 PMCID: PMC11172914 DOI: 10.3390/ijms25116144] [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: 03/03/2024] [Revised: 05/25/2024] [Accepted: 05/30/2024] [Indexed: 06/21/2024] Open
Abstract
The sodium channel NaV1.8, encoded by the SCN10A gene, has recently emerged as a potential regulator of cardiac electrophysiology. We have previously shown that NaV1.8 contributes to arrhythmogenesis by inducing a persistent Na+ current (late Na+ current, INaL) in human atrial and ventricular cardiomyocytes (CM). We now aim to further investigate the contribution of NaV1.8 to human ventricular arrhythmogenesis at the CM-specific level using pharmacological inhibition as well as a genetic knockout (KO) of SCN10A in induced pluripotent stem cell CM (iPSC-CM). In functional voltage-clamp experiments, we demonstrate that INaL was significantly reduced in ventricular SCN10A-KO iPSC-CM and in control CM after a specific pharmacological inhibition of NaV1.8. In contrast, we did not find any effects on ventricular APD90. The frequency of spontaneous sarcoplasmic reticulum Ca2+ sparks and waves were reduced in SCN10A-KO iPSC-CM and control cells following the pharmacological inhibition of NaV1.8. We further analyzed potential triggers of arrhythmias and found reduced delayed afterdepolarizations (DAD) in SCN10A-KO iPSC-CM and after the specific inhibition of NaV1.8 in control cells. In conclusion, we show that NaV1.8-induced INaL primarily impacts arrhythmogenesis at a subcellular level, with minimal effects on systolic cellular Ca2+ release. The inhibition or knockout of NaV1.8 diminishes proarrhythmic triggers in ventricular CM. In conjunction with our previously published results, this work confirms NaV1.8 as a proarrhythmic target that may be useful in an anti-arrhythmic therapeutic strategy.
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Affiliation(s)
- Nico Hartmann
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen and Rhein Main, 61231 Bad Nauheim, Germany
| | - Maria Knierim
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen and Rhein Main, 61231 Bad Nauheim, Germany
- Clinic for Cardio-Thoracic and Vascular Surgery, University Medical Center, 37075 Göttingen, Germany
| | - Wiebke Maurer
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen and Rhein Main, 61231 Bad Nauheim, Germany
| | - Nataliya Dybkova
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen and Rhein Main, 61231 Bad Nauheim, Germany
| | - Florian Zeman
- Center for Clinicial Trials, University of Regensburg, 93042 Regensburg, Germany
| | - Gerd Hasenfuß
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen and Rhein Main, 61231 Bad Nauheim, Germany
| | - Samuel Sossalla
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen and Rhein Main, 61231 Bad Nauheim, Germany
- Medical Clinic I, Cardiology and Angiology, Giessen and Department of Cardiology at Kerckhoff Heart and Lung Center, Justus-Liebig-University, 61231 Bad Nauheim, Germany
| | - Katrin Streckfuss-Bömeke
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen and Rhein Main, 61231 Bad Nauheim, Germany
- Institute of Pharmacology and Toxicology, University of Würzburg, 97078 Würzburg, Germany
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Ni H, Morotti S, Zhang X, Dobrev D, Grandi E. Integrative human atrial modelling unravels interactive protein kinase A and Ca2+/calmodulin-dependent protein kinase II signalling as key determinants of atrial arrhythmogenesis. Cardiovasc Res 2023; 119:2294-2311. [PMID: 37523735 PMCID: PMC11318383 DOI: 10.1093/cvr/cvad118] [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] [Received: 02/24/2023] [Revised: 05/18/2023] [Accepted: 06/05/2023] [Indexed: 08/02/2023] Open
Abstract
AIMS Atrial fibrillation (AF), the most prevalent clinical arrhythmia, is associated with atrial remodelling manifesting as acute and chronic alterations in expression, function, and regulation of atrial electrophysiological and Ca2+-handling processes. These AF-induced modifications crosstalk and propagate across spatial scales creating a complex pathophysiological network, which renders AF resistant to existing pharmacotherapies that predominantly target transmembrane ion channels. Developing innovative therapeutic strategies requires a systems approach to disentangle quantitatively the pro-arrhythmic contributions of individual AF-induced alterations. METHODS AND RESULTS Here, we built a novel computational framework for simulating electrophysiology and Ca2+-handling in human atrial cardiomyocytes and tissues, and their regulation by key upstream signalling pathways [i.e. protein kinase A (PKA), and Ca2+/calmodulin-dependent protein kinase II (CaMKII)] involved in AF-pathogenesis. Populations of atrial cardiomyocyte models were constructed to determine the influence of subcellular ionic processes, signalling components, and regulatory networks on atrial arrhythmogenesis. Our results reveal a novel synergistic crosstalk between PKA and CaMKII that promotes atrial cardiomyocyte electrical instability and arrhythmogenic triggered activity. Simulations of heterogeneous tissue demonstrate that this cellular triggered activity is further amplified by CaMKII- and PKA-dependent alterations of tissue properties, further exacerbating atrial arrhythmogenesis. CONCLUSIONS Our analysis reveals potential mechanisms by which the stress-associated adaptive changes turn into maladaptive pro-arrhythmic triggers at the cellular and tissue levels and identifies potential anti-AF targets. Collectively, our integrative approach is powerful and instrumental to assemble and reconcile existing knowledge into a systems network for identifying novel anti-AF targets and innovative approaches moving beyond the traditional ion channel-based strategy.
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Affiliation(s)
- Haibo Ni
- Department of Pharmacology, University of California Davis,
451 Health Sciences Drive, Davis, CA 95616, USA
| | - Stefano Morotti
- Department of Pharmacology, University of California Davis,
451 Health Sciences Drive, Davis, CA 95616, USA
| | - Xianwei Zhang
- Department of Pharmacology, University of California Davis,
451 Health Sciences Drive, Davis, CA 95616, USA
| | - Dobromir Dobrev
- Institute of Pharmacology, Faculty of Medicine, University
Duisburg-Essen, Essen, Germany
- Department of Medicine and Research Center, Montreal Heart Institute and
Université de Montréal, Montréal, Canada
- Department of Molecular Physiology and Biophysics, Baylor College of
Medicine, Houston, TX, USA
| | - Eleonora Grandi
- Department of Pharmacology, University of California Davis,
451 Health Sciences Drive, Davis, CA 95616, USA
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Ramos-Mondragón R, Lozhkin A, Vendrov AE, Runge MS, Isom LL, Madamanchi NR. NADPH Oxidases and Oxidative Stress in the Pathogenesis of Atrial Fibrillation. Antioxidants (Basel) 2023; 12:1833. [PMID: 37891912 PMCID: PMC10604902 DOI: 10.3390/antiox12101833] [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: 08/18/2023] [Revised: 09/26/2023] [Accepted: 09/29/2023] [Indexed: 10/29/2023] Open
Abstract
Atrial fibrillation (AF) is the most common type of cardiac arrhythmia and its prevalence increases with age. The irregular and rapid contraction of the atria can lead to ineffective blood pumping, local blood stasis, blood clots, ischemic stroke, and heart failure. NADPH oxidases (NOX) and mitochondria are the main sources of reactive oxygen species in the heart, and dysregulated activation of NOX and mitochondrial dysfunction are associated with AF pathogenesis. NOX- and mitochondria-derived oxidative stress contribute to the onset of paroxysmal AF by inducing electrophysiological changes in atrial myocytes and structural remodeling in the atria. Because high atrial activity causes cardiac myocytes to expend extremely high energy to maintain excitation-contraction coupling during persistent AF, mitochondria, the primary energy source, undergo metabolic stress, affecting their morphology, Ca2+ handling, and ATP generation. In this review, we discuss the role of oxidative stress in activating AF-triggered activities, regulating intracellular Ca2+ handling, and functional and anatomical reentry mechanisms, all of which are associated with AF initiation, perpetuation, and progression. Changes in the extracellular matrix, inflammation, ion channel expression and function, myofibril structure, and mitochondrial function occur during the early transitional stages of AF, opening a window of opportunity to target NOX and mitochondria-derived oxidative stress using isoform-specific NOX inhibitors and mitochondrial ROS scavengers, as well as drugs that improve mitochondrial dynamics and metabolism to treat persistent AF and its transition to permanent AF.
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Affiliation(s)
- Roberto Ramos-Mondragón
- Department of Pharmacology, University of Michigan, 1150 West Medical Center Drive, 2301 Medical Science Research Building III, Ann Arbor, MI 48109, USA; (R.R.-M.); (L.L.I.)
| | - Andrey Lozhkin
- Department of Internal Medicine, Frankel Cardiovascular Center, University of Michigan, Ann Arbor, MI 48019, USA; (A.L.); (A.E.V.); (M.S.R.)
| | - Aleksandr E. Vendrov
- Department of Internal Medicine, Frankel Cardiovascular Center, University of Michigan, Ann Arbor, MI 48019, USA; (A.L.); (A.E.V.); (M.S.R.)
| | - Marschall S. Runge
- Department of Internal Medicine, Frankel Cardiovascular Center, University of Michigan, Ann Arbor, MI 48019, USA; (A.L.); (A.E.V.); (M.S.R.)
| | - Lori L. Isom
- Department of Pharmacology, University of Michigan, 1150 West Medical Center Drive, 2301 Medical Science Research Building III, Ann Arbor, MI 48109, USA; (R.R.-M.); (L.L.I.)
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Nageswara R. Madamanchi
- Department of Internal Medicine, Frankel Cardiovascular Center, University of Michigan, Ann Arbor, MI 48019, USA; (A.L.); (A.E.V.); (M.S.R.)
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Tchou G, Ponce-Balbuena D, Liu N, Gore-Panter S, Hsu J, Liu F, Opoku E, Brubaker G, Schumacher SM, Moravec CS, Barnard J, Van Wagoner DR, Chung MK, Smith JD. Decreased FAM13B Expression Increases Atrial Fibrillation Susceptibility by Regulating Sodium Current and Calcium Handling. JACC Basic Transl Sci 2023; 8:1357-1378. [PMID: 38094680 PMCID: PMC10714175 DOI: 10.1016/j.jacbts.2023.05.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 05/16/2023] [Accepted: 05/16/2023] [Indexed: 04/17/2024]
Abstract
A specific genetic variant associated with atrial fibrillation risk, rs17171731, was identified as a regulatory variant responsible for controlling FAM13B expression. The atrial fibrillation risk allele decreases FAM13B expression, whose knockdown alters the expression of many genes in stem cell-derived cardiomyocytes, including SCN2B, and led to pro-arrhythmogenic changes in the late sodium current and Ca2+ cycling. Fam13b knockout mice had increased P-wave and QT interval duration and were more susceptible to pacing-induced arrhythmias vs control mice. FAM13B expression, its regulation, and downstream effects are potential targets for investigation of patient-specific therapeutics.
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Affiliation(s)
- Gregory Tchou
- Departments of Cardiovascular and Metabolic Sciences, Cleveland Clinic, Cleveland, Ohio, USA
| | | | - Nana Liu
- Departments of Cardiovascular and Metabolic Sciences, Cleveland Clinic, Cleveland, Ohio, USA
| | - Shamone Gore-Panter
- Departments of Cardiovascular and Metabolic Sciences, Cleveland Clinic, Cleveland, Ohio, USA
| | - Jeffrey Hsu
- Departments of Cardiovascular and Metabolic Sciences, Cleveland Clinic, Cleveland, Ohio, USA
| | - Fang Liu
- Departments of Cardiovascular and Metabolic Sciences, Cleveland Clinic, Cleveland, Ohio, USA
| | - Emmanuel Opoku
- Departments of Cardiovascular and Metabolic Sciences, Cleveland Clinic, Cleveland, Ohio, USA
| | - Gregory Brubaker
- Departments of Cardiovascular and Metabolic Sciences, Cleveland Clinic, Cleveland, Ohio, USA
| | - Sarah M. Schumacher
- Departments of Cardiovascular and Metabolic Sciences, Cleveland Clinic, Cleveland, Ohio, USA
| | - Christine S. Moravec
- Departments of Cardiovascular and Metabolic Sciences, Cleveland Clinic, Cleveland, Ohio, USA
- Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, Ohio, USA
| | - John Barnard
- Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, Ohio, USA
| | - David R. Van Wagoner
- Departments of Cardiovascular and Metabolic Sciences, Cleveland Clinic, Cleveland, Ohio, USA
- Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, Ohio, USA
| | - Mina K. Chung
- Departments of Cardiovascular and Metabolic Sciences, Cleveland Clinic, Cleveland, Ohio, USA
- Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, Ohio, USA
| | - Jonathan D. Smith
- Departments of Cardiovascular and Metabolic Sciences, Cleveland Clinic, Cleveland, Ohio, USA
- Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, Ohio, USA
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Karbowski M, Boyman L, Garber L, Joca HC, Verhoeven N, Coleman AK, Ward CW, Lederer WJ, Greiser M. Na + /K + ATPase-Ca v 1.2 nanodomain differentially regulates intracellular [Na + ], [Ca 2+ ] and local adrenergic signaling in cardiac myocytes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.31.553598. [PMID: 37693446 PMCID: PMC10491240 DOI: 10.1101/2023.08.31.553598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Background The intracellular Na + concentration ([Na + ] i ) is a crucial but understudied regulator of cardiac myocyte function. The Na + /K + ATPase (NKA) controls the steady-state [Na + ] i and thereby determines the set-point for intracellular Ca 2+ . Here, we investigate the nanoscopic organization and local adrenergic regulation of the NKA macromolecular complex and how it differentially regulates the intracellular Na + and Ca 2+ homeostases in atrial and ventricular myocytes. Methods Multicolor STORM super-resolution microscopy, Western Blot analyses, and in vivo examination of adrenergic regulation are employed to examine the organization and function of Na + nanodomains in cardiac myocytes. Quantitative fluorescence microscopy at high spatiotemporal resolution is used in conjunction with cellular electrophysiology to investigate intracellular Na + homeostasis in atrial and ventricular myocytes. Results The NKAα1 (NKAα1) and the L-type Ca 2+ -channel (Ca v 1.2) form a nanodomain with a center-to center distance of ∼65 nm in both ventricular and atrial myocytes. NKAα1 protein expression levels are ∼3 fold higher in atria compared to ventricle. 100% higher atrial I NKA , produced by large NKA "superclusters", underlies the substantially lower Na + concentration in atrial myocytes compared to the benchmark values set in ventricular myocytes. The NKA's regulatory protein phospholemman (PLM) has similar expression levels across atria and ventricle resulting in a much lower PLM/NKAα1 ratio for atrial compared to ventricular tissue. In addition, a huge PLM phosphorylation reserve in atrial tissue produces a high ß-adrenergic sensitivity of I NKA in atrial myocytes. ß-adrenergic regulation of I NKA is locally mediated in the NKAα1-Ca v 1.2 nanodomain via A-kinase anchoring proteins. Conclusions NKAα1, Ca v 1.2 and their accessory proteins form a structural and regulatory nanodomain at the cardiac dyad. The tissue-specific composition and local adrenergic regulation of this "signaling cloud" is a main regulator of the distinct global intracellular Na + and Ca 2+ concentrations in atrial and ventricular myocytes.
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9
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Hartmann N, Knierim M, Maurer W, Dybkova N, Hasenfuß G, Sossalla S, Streckfuss-Bömeke K. Molecular and Functional Relevance of Na V1.8-Induced Atrial Arrhythmogenic Triggers in a Human SCN10A Knock-Out Stem Cell Model. Int J Mol Sci 2023; 24:10189. [PMID: 37373335 DOI: 10.3390/ijms241210189] [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: 05/02/2023] [Revised: 05/26/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023] Open
Abstract
In heart failure and atrial fibrillation, a persistent Na+ current (INaL) exerts detrimental effects on cellular electrophysiology and can induce arrhythmias. We have recently shown that NaV1.8 contributes to arrhythmogenesis by inducing a INaL. Genome-wide association studies indicate that mutations in the SCN10A gene (NaV1.8) are associated with increased risk for arrhythmias, Brugada syndrome, and sudden cardiac death. However, the mediation of these NaV1.8-related effects, whether through cardiac ganglia or cardiomyocytes, is still a subject of controversial discussion. We used CRISPR/Cas9 technology to generate homozygous atrial SCN10A-KO-iPSC-CMs. Ruptured-patch whole-cell patch-clamp was used to measure the INaL and action potential duration. Ca2+ measurements (Fluo 4-AM) were performed to analyze proarrhythmogenic diastolic SR Ca2+ leak. The INaL was significantly reduced in atrial SCN10A KO CMs as well as after specific pharmacological inhibition of NaV1.8. No effects on atrial APD90 were detected in any groups. Both SCN10A KO and specific blockers of NaV1.8 led to decreased Ca2+ spark frequency and a significant reduction of arrhythmogenic Ca2+ waves. Our experiments demonstrate that NaV1.8 contributes to INaL formation in human atrial CMs and that NaV1.8 inhibition modulates proarrhythmogenic triggers in human atrial CMs and therefore NaV1.8 could be a new target for antiarrhythmic strategies.
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Affiliation(s)
- Nico Hartmann
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen and Rhein Main, 61231 Bad Nauheim, Germany
| | - Maria Knierim
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen and Rhein Main, 61231 Bad Nauheim, Germany
- Clinic for Cardio-Thoracic and Vascular Surgery, University Medical Center, 37075 Göttingen, Germany
| | - Wiebke Maurer
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen and Rhein Main, 61231 Bad Nauheim, Germany
| | - Nataliya Dybkova
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen and Rhein Main, 61231 Bad Nauheim, Germany
| | - Gerd Hasenfuß
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen and Rhein Main, 61231 Bad Nauheim, Germany
| | - Samuel Sossalla
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen and Rhein Main, 61231 Bad Nauheim, Germany
- Departments of Cardiology at Kerckhoff Heart and Lung Center, Bad Nauheim and University of Giessen, 61231 Bad Nauheim, Germany
| | - Katrin Streckfuss-Bömeke
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen and Rhein Main, 61231 Bad Nauheim, Germany
- Institute of Pharmacology and Toxicology, University of Würzburg, 97078 Würzburg, Germany
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10
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Serrano R, Feyen DAM, Bruyneel AAN, Hnatiuk AP, Vu MM, Amatya PL, Perea-Gil I, Prado M, Seeger T, Wu JC, Karakikes I, Mercola M. A deep learning platform to assess drug proarrhythmia risk. Cell Stem Cell 2023; 30:86-95.e4. [PMID: 36563695 PMCID: PMC9924077 DOI: 10.1016/j.stem.2022.12.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 10/25/2022] [Accepted: 11/29/2022] [Indexed: 12/24/2022]
Abstract
Drug safety initiatives have endorsed human iPSC-derived cardiomyocytes (hiPSC-CMs) as an in vitro model for predicting drug-induced cardiac arrhythmia. However, the extent to which human-defined features of in vitro arrhythmia predict actual clinical risk has been much debated. Here, we trained a convolutional neural network classifier (CNN) to learn features of in vitro action potential recordings of hiPSC-CMs that are associated with lethal Torsade de Pointes arrhythmia. The CNN classifier accurately predicted the risk of drug-induced arrhythmia in people. The risk profile of the test drugs was similar across hiPSC-CMs derived from different healthy donors. In contrast, pathogenic mutations that cause arrhythmogenic cardiomyopathies in patients significantly increased the proarrhythmic propensity to certain intermediate and high-risk drugs in the hiPSC-CMs. Thus, deep learning can identify in vitro arrhythmic features that correlate with clinical arrhythmia and discern the influence of patient genetics on the risk of drug-induced arrhythmia.
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Affiliation(s)
- Ricardo Serrano
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Medicine, Division of Cardiovascular Medicine, Stanford University, Stanford, CA 94305, USA
| | - Dries A M Feyen
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Medicine, Division of Cardiovascular Medicine, Stanford University, Stanford, CA 94305, USA
| | - Arne A N Bruyneel
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Medicine, Division of Cardiovascular Medicine, Stanford University, Stanford, CA 94305, USA
| | - Anna P Hnatiuk
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Medicine, Division of Cardiovascular Medicine, Stanford University, Stanford, CA 94305, USA
| | - Michelle M Vu
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Medicine, Division of Cardiovascular Medicine, Stanford University, Stanford, CA 94305, USA
| | - Prashila L Amatya
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Medicine, Division of Cardiovascular Medicine, Stanford University, Stanford, CA 94305, USA
| | - Isaac Perea-Gil
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Cardiothoracic Surgery, Stanford University, Stanford, CA 94305, USA
| | - Maricela Prado
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Cardiothoracic Surgery, Stanford University, Stanford, CA 94305, USA
| | - Timon Seeger
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Medicine, Division of Cardiovascular Medicine, Stanford University, Stanford, CA 94305, USA
| | - Joseph C Wu
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Medicine, Division of Cardiovascular Medicine, Stanford University, Stanford, CA 94305, USA
| | - Ioannis Karakikes
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Cardiothoracic Surgery, Stanford University, Stanford, CA 94305, USA
| | - Mark Mercola
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA; Department of Medicine, Division of Cardiovascular Medicine, Stanford University, Stanford, CA 94305, USA.
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11
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Jing Y, Yang R, Chen W, Ye Q. Anti-Arrhythmic Effects of Sodium-Glucose Co-Transporter 2 Inhibitors. Front Pharmacol 2022; 13:898718. [PMID: 35814223 PMCID: PMC9263384 DOI: 10.3389/fphar.2022.898718] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 05/04/2022] [Indexed: 12/11/2022] Open
Abstract
Arrhythmias are clinically prevalent with a high mortality rate. They impose a huge economic burden, thereby substantially affecting the quality of life. Sodium-glucose co-transporter 2 inhibitor (SGLT2i) is a new type of hypoglycemic drug, which can regulate blood glucose level safely and effectively. Additionally, it reduces the occurrence and progression of heart failure and cardiovascular events significantly. Recently, studies have found that SGLT2i can alleviate the occurrence and progression of cardiac arrhythmias; however, the exact mechanism remains unclear. In this review, we aimed to discuss and summarize new literature on different modes in which SGLT2i ameliorates the occurrence and development of cardiac arrhythmias.
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12
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Aluja D, Delgado-Tomás S, Ruiz-Meana M, Barrabés JA, Inserte J. Calpains as Potential Therapeutic Targets for Myocardial Hypertrophy. Int J Mol Sci 2022; 23:ijms23084103. [PMID: 35456920 PMCID: PMC9032729 DOI: 10.3390/ijms23084103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 03/26/2022] [Accepted: 04/06/2022] [Indexed: 11/25/2022] Open
Abstract
Despite advances in its treatment, heart failure remains a major cause of morbidity and mortality, evidencing an urgent need for novel mechanism-based targets and strategies. Myocardial hypertrophy, caused by a wide variety of chronic stress stimuli, represents an independent risk factor for the development of heart failure, and its prevention constitutes a clinical objective. Recent studies performed in preclinical animal models support the contribution of the Ca2+-dependent cysteine proteases calpains in regulating the hypertrophic process and highlight the feasibility of their long-term inhibition as a pharmacological strategy. In this review, we discuss the existing evidence implicating calpains in the development of cardiac hypertrophy, as well as the latest advances in unraveling the underlying mechanisms. Finally, we provide an updated overview of calpain inhibitors that have been explored in preclinical models of cardiac hypertrophy and the progress made in developing new compounds that may serve for testing the efficacy of calpain inhibition in the treatment of pathological cardiac hypertrophy.
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Affiliation(s)
- David Aluja
- Cardiovascular Diseases Research Group, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Hospital Universitari, Passeig Vall d’Hebron 119-129, 08035 Barcelona, Spain; (D.A.); (S.D.-T.); (M.R.-M.); (J.A.B.)
| | - Sara Delgado-Tomás
- Cardiovascular Diseases Research Group, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Hospital Universitari, Passeig Vall d’Hebron 119-129, 08035 Barcelona, Spain; (D.A.); (S.D.-T.); (M.R.-M.); (J.A.B.)
| | - Marisol Ruiz-Meana
- Cardiovascular Diseases Research Group, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Hospital Universitari, Passeig Vall d’Hebron 119-129, 08035 Barcelona, Spain; (D.A.); (S.D.-T.); (M.R.-M.); (J.A.B.)
- Centro de Investigación en Red de Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain
| | - José A. Barrabés
- Cardiovascular Diseases Research Group, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Hospital Universitari, Passeig Vall d’Hebron 119-129, 08035 Barcelona, Spain; (D.A.); (S.D.-T.); (M.R.-M.); (J.A.B.)
- Centro de Investigación en Red de Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain
| | - Javier Inserte
- Cardiovascular Diseases Research Group, Vall d’Hebron Institut de Recerca (VHIR), Vall d’Hebron Hospital Universitari, Passeig Vall d’Hebron 119-129, 08035 Barcelona, Spain; (D.A.); (S.D.-T.); (M.R.-M.); (J.A.B.)
- Centro de Investigación en Red de Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain
- Correspondence: ; Tel.: +34-934894038
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13
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Ranolazine: An Old Drug with Emerging Potential; Lessons from Pre-Clinical and Clinical Investigations for Possible Repositioning. Pharmaceuticals (Basel) 2021; 15:ph15010031. [PMID: 35056088 PMCID: PMC8777683 DOI: 10.3390/ph15010031] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 12/16/2021] [Accepted: 12/20/2021] [Indexed: 02/07/2023] Open
Abstract
Ischemic heart disease is a significant public health problem with high mortality and morbidity. Extensive scientific investigations from basic sciences to clinics revealed multilevel alterations from metabolic imbalance, altered electrophysiology, and defective Ca2+/Na+ homeostasis leading to lethal arrhythmias. Despite the recent identification of numerous molecular targets with potential therapeutic interest, a pragmatic observation on the current pharmacological R&D output confirms the lack of new therapeutic offers to patients. By contrast, from recent trials, molecules initially developed for other fields of application have shown cardiovascular benefits, as illustrated with some anti-diabetic agents, regardless of the presence or absence of diabetes, emphasizing the clear advantage of “old” drug repositioning. Ranolazine is approved as an antianginal agent and has a favorable overall safety profile. This drug, developed initially as a metabolic modulator, was also identified as an inhibitor of the cardiac late Na+ current, although it also blocks other ionic currents, including the hERG/Ikr K+ current. The latter actions have been involved in this drug’s antiarrhythmic effects, both on supraventricular and ventricular arrhythmias (VA). However, despite initial enthusiasm and promising development in the cardiovascular field, ranolazine is only authorized as a second-line treatment in patients with chronic angina pectoris, notwithstanding its antiarrhythmic properties. A plausible reason for this is the apparent difficulty in linking the clinical benefits to the multiple molecular actions of this drug. Here, we review ranolazine’s experimental and clinical knowledge on cardiac metabolism and arrhythmias. We also highlight advances in understanding novel effects on neurons, the vascular system, skeletal muscles, blood sugar control, and cancer, which may open the way to reposition this “old” drug alone or in combination with other medications.
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14
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Detrimental proarrhythmogenic interaction of Ca 2+/calmodulin-dependent protein kinase II and Na V1.8 in heart failure. Nat Commun 2021; 12:6586. [PMID: 34782600 PMCID: PMC8593192 DOI: 10.1038/s41467-021-26690-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 10/14/2021] [Indexed: 12/19/2022] Open
Abstract
An interplay between Ca2+/calmodulin-dependent protein kinase IIδc (CaMKIIδc) and late Na+ current (INaL) is known to induce arrhythmias in the failing heart. Here, we elucidate the role of the sodium channel isoform NaV1.8 for CaMKIIδc-dependent proarrhythmia. In a CRISPR-Cas9-generated human iPSC-cardiomyocyte homozygous knock-out of NaV1.8, we demonstrate that NaV1.8 contributes to INaL formation. In addition, we reveal a direct interaction between NaV1.8 and CaMKIIδc in cardiomyocytes isolated from patients with heart failure (HF). Using specific blockers of NaV1.8 and CaMKIIδc, we show that NaV1.8-driven INaL is CaMKIIδc-dependent and that NaV1.8-inhibtion reduces diastolic SR-Ca2+ leak in human failing cardiomyocytes. Moreover, increased mortality of CaMKIIδc-overexpressing HF mice is reduced when a NaV1.8 knock-out is introduced. Cellular and in vivo experiments reveal reduced ventricular arrhythmias without changes in HF progression. Our work therefore identifies a proarrhythmic CaMKIIδc downstream target which may constitute a prognostic and antiarrhythmic strategy.
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15
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Avula UMR, Dridi H, Chen BX, Yuan Q, Katchman AN, Reiken SR, Desai AD, Parsons S, Baksh H, Ma E, Dasrat P, Ji R, Lin Y, Sison C, Lederer WJ, Joca HC, Ward CW, Greiser M, Marks AR, Marx SO, Wan EY. Attenuating persistent sodium current-induced atrial myopathy and fibrillation by preventing mitochondrial oxidative stress. JCI Insight 2021; 6:e147371. [PMID: 34710060 PMCID: PMC8675199 DOI: 10.1172/jci.insight.147371] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 10/27/2021] [Indexed: 12/19/2022] Open
Abstract
Mechanistically driven therapies for atrial fibrillation (AF), the most common cardiac arrhythmia, are urgently needed, the development of which requires improved understanding of the cellular signaling pathways that facilitate the structural and electrophysiological remodeling that occurs in the atria. Similar to humans, increased persistent Na+ current leads to the development of an atrial myopathy and spontaneous and long-lasting episodes of AF in mice. How increased persistent Na+ current causes both structural and electrophysiological remodeling in the atria is unknown. We crossbred mice expressing human F1759A-NaV1.5 channels with mice expressing human mitochondrial catalase (mCAT). Increased expression of mCAT attenuated mitochondrial and cellular reactive oxygen species (ROS) and the structural remodeling that was induced by persistent F1759A-Na+ current. Despite the heterogeneously prolonged atrial action potential, which was unaffected by the reduction in ROS, the incidences of spontaneous AF, pacing-induced after-depolarizations, and AF were substantially reduced. Expression of mCAT markedly reduced persistent Na+ current-induced ryanodine receptor oxidation and dysfunction. In summary, increased persistent Na+ current in atrial cardiomyocytes, which is observed in patients with AF, induced atrial enlargement, fibrosis, mitochondrial dysmorphology, early after-depolarizations, and AF, all of which can be attenuated by resolving mitochondrial oxidative stress.
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Affiliation(s)
| | - Haikel Dridi
- Department of Physiology and Cellular Biophysics and Clyde & Helen Wu Center for Molecular Cardiology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Bi-xing Chen
- Division of Cardiology, Department of Medicine, and
| | - Qi Yuan
- Department of Physiology and Cellular Biophysics and Clyde & Helen Wu Center for Molecular Cardiology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | | | - Steven R. Reiken
- Department of Physiology and Cellular Biophysics and Clyde & Helen Wu Center for Molecular Cardiology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | | | | | - Haajra Baksh
- Division of Cardiology, Department of Medicine, and
| | - Elaine Ma
- Division of Cardiology, Department of Medicine, and
| | | | - Ruiping Ji
- Division of Cardiology, Department of Medicine, and
| | - Yejun Lin
- Division of Cardiology, Department of Medicine, and
| | | | - W. Jonathan Lederer
- Center for Biomedical Engineering and Technology and Department of Physiology and
| | - Humberto C. Joca
- Center for Biomedical Engineering and Technology and Department of Physiology and
| | - Christopher W. Ward
- Center for Biomedical Engineering and Technology and Department of Physiology and
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Maura Greiser
- Center for Biomedical Engineering and Technology and Department of Physiology and
| | - Andrew R. Marks
- Department of Physiology and Cellular Biophysics and Clyde & Helen Wu Center for Molecular Cardiology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Steven O. Marx
- Division of Cardiology, Department of Medicine, and
- Department of Molecular Pharmacology and Therapeutics, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
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16
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Kwon HK, Choi H, Park SG, Park WJ, Kim, DH, Park ZY. Integrated Quantitative Phosphoproteomics and Cell-based Functional Screening Reveals Specific Pathological Cardiac Hypertrophy-related Phosphorylation Sites. Mol Cells 2021; 44:500-516. [PMID: 34158421 PMCID: PMC8334354 DOI: 10.14348/molcells.2021.4002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Accepted: 01/07/2019] [Indexed: 12/29/2022] Open
Abstract
Cardiac hypertrophic signaling cascades resulting in heart failure diseases are mediated by protein phosphorylation. Recent developments in mass spectrometry-based phosphoproteomics have led to the identification of thousands of differentially phosphorylated proteins and their phosphorylation sites. However, functional studies of these differentially phosphorylated proteins have not been conducted in a large-scale or high-throughput manner due to a lack of methods capable of revealing the functional relevance of each phosphorylation site. In this study, an integrated approach combining quantitative phosphoproteomics and cell-based functional screening using phosphorylation competition peptides was developed. A pathological cardiac hypertrophy model, junctate-1 transgenic mice and control mice, were analyzed using label-free quantitative phosphoproteomics to identify differentially phosphorylated proteins and sites. A cell-based functional assay system measuring hypertrophic cell growth of neonatal rat ventricle cardiomyocytes (NRVMs) following phenylephrine treatment was applied, and changes in phosphorylation of individual differentially phosphorylated sites were induced by incorporation of phosphorylation competition peptides conjugated with cell-penetrating peptides. Cell-based functional screening against 18 selected phosphorylation sites identified three phosphorylation sites (Ser-98, Ser-179 of Ldb3, and Ser-1146 of palladin) displaying near-complete inhibition of cardiac hypertrophic growth of NRVMs. Changes in phosphorylation levels of Ser-98 and Ser-179 in Ldb3 were further confirmed in NRVMs and other pathological/physiological hypertrophy models, including transverse aortic constriction and swimming models, using site-specific phospho-antibodies. Our integrated approach can be used to identify functionally important phosphorylation sites among differentially phosphorylated sites, and unlike conventional approaches, it is easily applicable for large-scale and/or high-throughput analyses.
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Affiliation(s)
- Hye Kyeong Kwon
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Hyunwoo Choi
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Sung-Gyoo Park
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Woo Jin Park
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Do Han Kim,
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
| | - Zee-Yong Park
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
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17
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Fong SPT, Agrawal S, Gong M, Zhao J. Modulated Calcium Homeostasis and Release Events Under Atrial Fibrillation and Its Risk Factors: A Meta-Analysis. Front Cardiovasc Med 2021; 8:662914. [PMID: 34355025 PMCID: PMC8329373 DOI: 10.3389/fcvm.2021.662914] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 06/11/2021] [Indexed: 12/26/2022] Open
Abstract
Background: Atrial fibrillation (AF) is associated with calcium (Ca2+) handling remodeling and increased spontaneous calcium release events (SCaEs). Nevertheless, its exact mechanism remains unclear, resulting in suboptimal primary and secondary preventative strategies. Methods: We searched the PubMed database for studies that investigated the relationship between SCaEs and AF and/or its risk factors. Meta-analysis was used to examine the Ca2+ mechanisms involved in the primary and secondary AF preventative groups. Results: We included a total of 74 studies, out of the identified 446 publications from inception (1982) until March 31, 2020. Forty-five were primary and 29 were secondary prevention studies for AF. The main Ca2+ release events, calcium transient (standardized mean difference (SMD) = 0.49; I2 = 35%; confidence interval (CI) = 0.33–0.66; p < 0.0001), and spark amplitude (SMD = 0.48; I2 = 0%; CI = −0.98–1.93; p = 0.054) were enhanced in the primary diseased group, while calcium transient frequency was increased in the secondary group. Calcium spark frequency was elevated in both the primary diseased and secondary AF groups. One of the key cardiac currents, the L-type calcium current (ICaL) was significantly downregulated in primary diseased (SMD = −1.07; I2 = 88%; CI = −1.94 to −0.20; p < 0.0001) and secondary AF groups (SMD = −1.28; I2 = 91%; CI = −2.04 to −0.52; p < 0.0001). Furthermore, the sodium–calcium exchanger (INCX) and NCX1 protein expression were significantly enhanced in the primary diseased group, while only NCX1 protein expression was shown to increase in the secondary AF studies. The phosphorylation of the ryanodine receptor at S2808 (pRyR-S2808) was significantly elevated in both the primary and secondary groups. It was increased in the primary diseased and proarrhythmic subgroups (SMD = 0.95; I2 = 64%; CI = 0.12–1.79; p = 0.074) and secondary AF group (SMD = 0.66; I2 = 63%; CI = 0.01–1.31; p < 0.0001). Sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) expression was elevated in the primary diseased and proarrhythmic drug subgroups but substantially reduced in the secondary paroxysmal AF subgroup. Conclusions: Our study identified that ICaL is reduced in both the primary and secondary diseased groups. Furthermore, pRyR-S2808 and NCX1 protein expression are enhanced. The remodeling leads to elevated Ca2+ functional activities, such as increased frequencies or amplitude of Ca2+ spark and Ca2+ transient. The main difference identified between the primary and secondary diseased groups is SERCA expression, which is elevated in the primary diseased group and substantially reduced in the secondary paroxysmal AF subgroup. We believe our study will add new evidence to AF mechanisms and treatment targets.
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Affiliation(s)
- Sarah Pei Ting Fong
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Shaleka Agrawal
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Mengqi Gong
- Department of Cardiology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Jichao Zhao
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
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18
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Pabel S, Mustroph J, Stehle T, Lebek S, Dybkova N, Keyser A, Rupprecht L, Wagner S, Neef S, Maier LS, Sossalla S. Dantrolene reduces CaMKIIδC-mediated atrial arrhythmias. Europace 2021; 22:1111-1118. [PMID: 32413138 DOI: 10.1093/europace/euaa079] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 02/10/2020] [Accepted: 03/17/2020] [Indexed: 01/29/2023] Open
Abstract
AIMS In atrial fibrillation (AF), an increased diastolic Ca2+ leak from the sarcoplasmic reticulum (SR) mediated by calcium/calmodulin-dependent-protein-kinaseIIδC (CaMKII) can serve as a substrate for arrhythmia induction and persistence. Dantrolene has been shown to stabilize the cardiac ryanodine-receptor. This study investigated the effects of dantrolene on arrhythmogenesis in human and mouse atria with enhanced CaMKII activity. METHODS AND RESULTS Human atrial cardiomyocytes (CMs) were isolated from patients with AF. To investigate CaMKII-mediated arrhythmogenesis, atrial CMs from mice overexpressing CaMKIIδC (TG) and the respective wildtype (WT) were studied using confocal microscopy (Fluo-4), patch-clamp technique, and in vivo atrial catheter-based burst stimulations. Dantrolene potently reduced Ca2+ spark frequency (CaSpF) and diastolic SR Ca2+ leak in AF CMs. Additional CaMKII inhibition did not further reduce CaSpF or leak compared to dantrolene alone. While the increased SR CaSpF and leak in TG mice were reduced by dantrolene, no effects could be detected in WT. Dantrolene also potently reduced the pathologically enhanced frequency of diastolic SR Ca2+ waves in TG without having effects in WT. As an increased diastolic SR Ca2+ release can induce a depolarizing transient inward current, we could demonstrate that the incidence of afterdepolarizations in TG, but not in WT, mice was significantly diminished in the presence of dantrolene. To translate these findings into an in vivo situation we could show that dantrolene strongly suppressed the inducibility of AF in vivo in TG mice. CONCLUSION Dantrolene reduces CaMKII-mediated atrial arrhythmogenesis and may therefore constitute an interesting antiarrhythmic drug for treating patients with atrial arrhythmias driven by an enhanced CaMKII activity, such as AF.
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Affiliation(s)
- Steffen Pabel
- Department of Internal Medicine II, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany
| | - Julian Mustroph
- Department of Internal Medicine II, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany
| | - Thea Stehle
- Department of Internal Medicine II, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany
| | - Simon Lebek
- Department of Internal Medicine II, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany
| | - Nataliya Dybkova
- Clinic for Cardiology & Pneumology, Georg-August University Göttingen, DZHK (German Center for Cardiovascular Research), Partner Site Göttingen, Robert Koch Str. 40, 37075 Göttingen, Germany
| | - Andreas Keyser
- Department of Cardiothoracic Surgery, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany
| | - Leopold Rupprecht
- Department of Cardiothoracic Surgery, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany
| | - Stefan Wagner
- Department of Internal Medicine II, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany
| | - Stefan Neef
- Department of Internal Medicine II, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany
| | - Lars S Maier
- Department of Internal Medicine II, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany
| | - Samuel Sossalla
- Department of Internal Medicine II, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany.,Clinic for Cardiology & Pneumology, Georg-August University Göttingen, DZHK (German Center for Cardiovascular Research), Partner Site Göttingen, Robert Koch Str. 40, 37075 Göttingen, Germany
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19
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Zhang Y, Qi Y, Li JJ, He WJ, Gao XH, Zhang Y, Sun X, Tong J, Zhang J, Deng XL, Du XJ, Xie W. Stretch-induced sarcoplasmic reticulum calcium leak is causatively associated with atrial fibrillation in pressure-overloaded hearts. Cardiovasc Res 2021; 117:1091-1102. [PMID: 32531044 DOI: 10.1093/cvr/cvaa163] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 01/06/2020] [Accepted: 06/05/2020] [Indexed: 12/21/2022] Open
Abstract
AIMS Despite numerous reports documenting an important role of hypertension in the development of atrial fibrillation (AF), the detailed mechanism underlying the pathological process remains incompletely understood. Here, we aim to test the hypothesis that diastolic sarcoplasmic reticulum (SR) Ca2+ leak in atrial myocytes, induced by mechanical stretch due to elevated pressure in the left atrium (LA), plays an essential role in the AF development in pressure-overloaded hearts. METHODS AND RESULTS Isolated mouse atrial myocytes subjected to acute axial stretch displayed an immediate elevation of SR Ca2+ leak. Using a mouse model of transverse aortic constriction (TAC), the relation between stretch, SR Ca2+ leak, and AF susceptibility was further tested. At 36 h post-TAC, SR Ca2+ leak in cardiomyocytes from the LA (with haemodynamic stress), but not right atrium (without haemodynamic stress), significantly increased, which was further elevated at 4 weeks post-TAC. Accordingly, AF susceptibility to atrial burst pacing in the 4-week TAC mice were also significantly increased, which was unaffected by inhibition of atrial fibrosis or inflammation via deletion of galectin-3. Western blotting revealed that type 2 ryanodine receptor (RyR2) in left atrial myocytes of TAC mice was oxidized due to activation and up-regulation of Nox2 and Nox4. Direct rescue of dysfunctional RyR2 with dantrolene or rycal S107 reduced diastolic SR Ca2+ leak in left atrial myocytes and prevented atrial burst pacing stimulated AF. CONCLUSION Our study demonstrated for the first time the increased SR Ca2+ leak mediated by enhanced oxidative stress in left atrial myocytes that is causatively associated with higher AF susceptibility in pressure-overloaded hearts.
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Affiliation(s)
- Yi Zhang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Ying Qi
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, No. 28 West Xianning Road, Xi'an, Shaanxi 710049, China
| | - Jing-Jing Li
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, No. 28 West Xianning Road, Xi'an, Shaanxi 710049, China
| | - Wen-Jin He
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, No. 28 West Xianning Road, Xi'an, Shaanxi 710049, China
| | - Xiao-Hang Gao
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, No. 28 West Xianning Road, Xi'an, Shaanxi 710049, China
| | - Yu Zhang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Xia Sun
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Jie Tong
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, No. 28 West Xianning Road, Xi'an, Shaanxi 710049, China
| | - Jianbao Zhang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, No. 28 West Xianning Road, Xi'an, Shaanxi 710049, China
| | - Xiu-Ling Deng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
- Cardiovascular Research Centre, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Xiao-Jun Du
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Wenjun Xie
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, No. 28 West Xianning Road, Xi'an, Shaanxi 710049, China
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20
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Mesubi OO, Rokita AG, Abrol N, Wu Y, Chen B, Wang Q, Granger JM, Tucker-Bartley A, Luczak ED, Murphy KR, Umapathi P, Banerjee PS, Boronina TN, Cole RN, Maier LS, Wehrens XH, Pomerantz JL, Song LS, Ahima RS, Hart GW, Zachara NE, Anderson ME. Oxidized CaMKII and O-GlcNAcylation cause increased atrial fibrillation in diabetic mice by distinct mechanisms. J Clin Invest 2021; 131:95747. [PMID: 33151911 PMCID: PMC7810480 DOI: 10.1172/jci95747] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 11/03/2020] [Indexed: 12/21/2022] Open
Abstract
Diabetes mellitus (DM) and atrial fibrillation (AF) are major unsolved public health problems, and diabetes is an independent risk factor for AF. However, the mechanism(s) underlying this clinical association is unknown. ROS and protein O-GlcNAcylation (OGN) are increased in diabetic hearts, and calmodulin kinase II (CaMKII) is a proarrhythmic signal that may be activated by ROS (oxidized CaMKII, ox-CaMKII) and OGN (OGN-CaMKII). We induced type 1 (T1D) and type 2 DM (T2D) in a portfolio of genetic mouse models capable of dissecting the role of ROS and OGN at CaMKII and global OGN in diabetic AF. Here, we showed that T1D and T2D significantly increased AF, and this increase required CaMKII and OGN. T1D and T2D both required ox-CaMKII to increase AF; however, we did not detect OGN-CaMKII or a role for OGN-CaMKII in diabetic AF. Collectively, our data affirm CaMKII as a critical proarrhythmic signal in diabetic AF and suggest ROS primarily promotes AF by ox-CaMKII, while OGN promotes AF by a CaMKII-independent mechanism(s). These results provide insights into the mechanisms for increased AF in DM and suggest potential benefits for future CaMKII and OGN targeted therapies.
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Affiliation(s)
- Olurotimi O. Mesubi
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Adam G. Rokita
- Division of Cardiovascular Medicine and Cardiovascular Research Center, Carver College of Medicine, Iowa City, Iowa, USA
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Neha Abrol
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Yuejin Wu
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Biyi Chen
- Division of Cardiovascular Medicine and Cardiovascular Research Center, Carver College of Medicine, Iowa City, Iowa, USA
| | - Qinchuan Wang
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jonathan M. Granger
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Anthony Tucker-Bartley
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Elizabeth D. Luczak
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Kevin R. Murphy
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Priya Umapathi
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Partha S. Banerjee
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Tatiana N. Boronina
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Robert N. Cole
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Lars S. Maier
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Xander H. Wehrens
- Department of Molecular Physiology and Biophysics, Department of Medicine (Cardiology), Department of Pediatrics, and Center for Space Medicine, Baylor College of Medicine, Houston, Texas, USA
| | - Joel L. Pomerantz
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Institute for Cell Engineering
| | - Long-Sheng Song
- Division of Cardiovascular Medicine and Cardiovascular Research Center, Carver College of Medicine, Iowa City, Iowa, USA
| | - Rexford S. Ahima
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine
| | - Gerald W. Hart
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Natasha E. Zachara
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Mark E. Anderson
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Medicine, and
- Department of Physiology and Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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21
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Dewal RS, Greer-Short A, Lane C, Nirengi S, Manzano PA, Hernández-Saavedra D, Wright KR, Nassal D, Baer LA, Mohler PJ, Hund TJ, Stanford KI. Phospho-ablation of cardiac sodium channel Na v1.5 mitigates susceptibility to atrial fibrillation and improves glucose homeostasis under conditions of diet-induced obesity. Int J Obes (Lond) 2021; 45:795-807. [PMID: 33500550 PMCID: PMC8005377 DOI: 10.1038/s41366-021-00742-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 11/19/2020] [Accepted: 01/04/2021] [Indexed: 01/30/2023]
Abstract
BACKGROUND Atrial fibrillation (AF) is the most common sustained arrhythmia, with growing evidence identifying obesity as an important risk factor for the development of AF. Although defective atrial myocyte excitability due to stress-induced remodeling of ion channels is commonly observed in the setting of AF, little is known about the mechanistic link between obesity and AF. Recent studies have identified increased cardiac late sodium current (INa,L) downstream of calmodulin-dependent kinase II (CaMKII) activation as an important driver of AF susceptibility. METHODS Here, we investigated a possible role for CaMKII-dependent INa,L in obesity-induced AF using wild-type (WT) and whole-body knock-in mice that ablates phosphorylation of the Nav1.5 sodium channel and prevents augmentation of the late sodium current (S571A; SA mice). RESULTS A high-fat diet (HFD) increased susceptibility to arrhythmias in WT mice, while SA mice were protected from this effect. Unexpectedly, SA mice had improved glucose homeostasis and decreased body weight compared to WT mice. However, SA mice also had reduced food consumption compared to WT mice. Controlling for food consumption through pair feeding of WT and SA mice abrogated differences in weight gain and AF inducibility, but not atrial fibrosis, premature atrial contractions or metabolic capacity. CONCLUSIONS These data demonstrate a novel role for CaMKII-dependent regulation of Nav1.5 in mediating susceptibility to arrhythmias and whole-body metabolism under conditions of diet-induced obesity.
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Affiliation(s)
- Revati S. Dewal
- grid.412332.50000 0001 1545 0811Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Center for Diabetes and Metabolism Research Center, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA
| | - Amara Greer-Short
- grid.261331.40000 0001 2285 7943Department of Biomedical Engineering, The Ohio State University, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA
| | - Cemantha Lane
- grid.261331.40000 0001 2285 7943Department of Biomedical Engineering, The Ohio State University, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA
| | - Shinsuke Nirengi
- grid.412332.50000 0001 1545 0811Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Center for Diabetes and Metabolism Research Center, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA
| | - Pedro Acosta Manzano
- grid.412332.50000 0001 1545 0811Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Center for Diabetes and Metabolism Research Center, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA
| | - Diego Hernández-Saavedra
- grid.412332.50000 0001 1545 0811Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Center for Diabetes and Metabolism Research Center, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA
| | - Katherine R. Wright
- grid.412332.50000 0001 1545 0811Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Center for Diabetes and Metabolism Research Center, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA
| | - Drew Nassal
- grid.261331.40000 0001 2285 7943Department of Biomedical Engineering, The Ohio State University, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA
| | - Lisa A. Baer
- grid.412332.50000 0001 1545 0811Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Center for Diabetes and Metabolism Research Center, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA
| | - Peter J. Mohler
- grid.412332.50000 0001 1545 0811Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus, OH USA
| | - Thomas J. Hund
- grid.261331.40000 0001 2285 7943Department of Biomedical Engineering, The Ohio State University, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus, OH USA
| | - Kristin I. Stanford
- grid.412332.50000 0001 1545 0811Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Center for Diabetes and Metabolism Research Center, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH USA ,grid.412332.50000 0001 1545 0811Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus, OH USA
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22
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Zhabyeyev P, Chen X, Vanhaesebroeck B, Oudit GY. PI3Kα in cardioprotection: Cytoskeleton, late Na + current, and mechanism of arrhythmias. Channels (Austin) 2020; 13:520-532. [PMID: 31790629 PMCID: PMC6930018 DOI: 10.1080/19336950.2019.1697127] [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] [Indexed: 12/19/2022] Open
Abstract
PI 3-kinase α (PI3Kα) is a lipid kinase that converts phosphatidylinositol-4,5-bisphosphate (PIP2) to phosphatidylinositol-3,4,5-triphosphate (PIP3). PI3Kα regulates a variety of cellular processes such as nutrient sensing, cell cycle, migration, and others. Heightened activity of PI3Kα in many types of cancer made it a prime oncology drug target, but also raises concerns of possible adverse effects on the heart. Indeed, recent advances in preclinical models demonstrate an important role of PI3Kα in the control of cytoskeletal integrity, Na+ channel activity, cardioprotection, and prevention of arrhythmias.
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Affiliation(s)
- Pavel Zhabyeyev
- Department of Medicine, University of Alberta, Edmonton, Canada.,Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Canada
| | - Xueyi Chen
- Department of Medicine, University of Alberta, Edmonton, Canada.,Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Canada
| | | | - Gavin Y Oudit
- Department of Medicine, University of Alberta, Edmonton, Canada.,Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Canada
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23
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Contribution of the neuronal sodium channel Na V1.8 to sodium- and calcium-dependent cellular proarrhythmia. J Mol Cell Cardiol 2020; 144:35-46. [PMID: 32418916 DOI: 10.1016/j.yjmcc.2020.05.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Revised: 04/17/2020] [Accepted: 05/05/2020] [Indexed: 12/19/2022]
Abstract
OBJECTIVE In myocardial pathology such as heart failure a late sodium current (INaL) augmentation is known to be involved in conditions of arrhythmogenesis. However, the underlying mechanisms of the INaL generation are not entirely understood. By now evidence is growing that non-cardiac sodium channel isoforms could also be involved in the INaL generation. The present study investigates the contribution of the neuronal sodium channel isoform NaV1.8 to arrhythmogenesis in a clearly-defined setting of enhanced INaL by using anemone toxin II (ATX-II) in the absence of structural heart disease. METHODS Electrophysiological experiments were performed in order to measure INaL, action potential duration (APD), SR-Ca2+-leak and cellular proarrhythmic triggers in ATX-II exposed wild-type (WT) and SCN10A-/- mice cardiomyocytes. In addition, WT cardiomyocytes were stimulated with ATX-II in the presence or absence of NaV1.8 inhibitors. INCX was measured by using the whole cell patch clamp method. RESULTS In WT cardiomyocytes exposure to ATX-II augmented INaL, prolonged APD, increased SR-Ca2+-leak and induced proarrhythmic triggers such as early afterdepolarizations (EADs) and Ca2+-waves. All of them could be significantly reduced by applying NaV1.8 blockers PF-01247324 and A-803467. Both blockers had no relevant effects on cellular electrophysiology of SCN10A-/- cardiomyocytes. Moreover, in SCN10A-/--cardiomyocytes, the ATX-II-dependent increase in INaL, SR-Ca2+-leak and APD prolongation was less than in WT and comparable to the results which were obtained with WT cardiomyocytes being exposed to ATX-II and NaV1.8 inhibitors in parallel. Moreover, we found a decrease in reverse mode NCX current and reduced CaMKII-dependent RyR2-phosphorylation after application of PF-01247324 as an underlying explanation for the Na+-mediated Ca2+-dependent proarrhythmic triggers. CONCLUSION The current findings demonstrate that NaV1.8 is a significant contributor for INaL-induced arrhythmic triggers. Therefore, NaV1.8 inhibition under conditions of an enhanced INaL constitutes a promising antiarrhythmic strategy which merits further investigation.
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24
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Yoshitomi H, Zhou J, Nishigaki T, Li W, Liu T, Wu L, Gao M. Morinda citrifolia (Noni) fruit juice promotes vascular endothelium function in hypertension via glucagon-like peptide-1 receptor-CaMKKβ-AMPK-eNOS pathway. Phytother Res 2020; 34:2341-2350. [PMID: 32298014 DOI: 10.1002/ptr.6685] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 03/12/2020] [Accepted: 03/16/2020] [Indexed: 12/15/2022]
Abstract
Morinda citrifolia (Noni) is extensively used in herbal remedies to prevent and treat various diseases, including hypertension. The purpose of this study was to investigate the vascular effects of noni fruit juice and characterize the upstream signaling pathways. We measured the systolic blood pressure, diastolic blood pressure, 24-hr urinary nitric oxide (NO) metabolite excretion, bodyweight (BW), and urine examination in SHR.Cg-Leprcp/NDmcr (SHR/cp) rats after 6 weeks noni juice (15 ml/kg) treatment. Noni juice significantly decreased blood pressure and 24-hr urinary NO metabolite without change of BW or urine volume. Furthermore, the noni juice extract (NJE) promoted endothelial vasorelaxation in rat aorta rings and NO product through an increase in phosphorylation of endothelial nitric oxide synthase (eNOS) in human umbilical vein endothelial cells (HUVECs). NJE might act on a glucagon like peptide-1 receptor (GLP-1R) via Ca2+ /calmodulin-dependent protein kinase kinase β (CaMKKβ)-AMPK signaling with pretreatment of their inhibitors or antagonist in HUVECs. Deacetylasperulosidic acid (DAA) was an active compound in noni juice to improve NO release through same pathway in HUVECs. These results suggested that noni is a novel dietary plant that probably regulates GLP-1R-induced CaMKKβ-AMPK-eNOS pathway to improve endothelium-dependent relaxation, thus reduce the blood pressure probably via one of its responsible ingredient DAA.
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Affiliation(s)
- Hisae Yoshitomi
- School of Pharmaceutical Sciences, Mukogawa Women's University, Nishinomiya, Hyogo, Japan
| | - Jingxin Zhou
- Department of Nephrology and Endocrinology, Dongzhimen Hospital Affilated to Beijing University of Chinese Medicine, Tongzhou, Beijing, People's Republic of China
| | | | - Wei Li
- Faculty of Pharmaceutical Sciences, Toho University, Chiba, Japan
| | - Tonghua Liu
- Beijing University of Chinese Medicine, Chaoyang, Beijing, People's Republic of China
| | - Lili Wu
- Beijing University of Chinese Medicine, Chaoyang, Beijing, People's Republic of China
| | - Ming Gao
- School of Pharmaceutical Sciences, Mukogawa Women's University, Nishinomiya, Hyogo, Japan.,Department of Cell Life Analytics, Institute for Biosciences, Mukogawa Women's University, Nishinomiya, Hyogo, Japan
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25
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Pabel S, Ahmad S, Tirilomis P, Stehle T, Mustroph J, Knierim M, Dybkova N, Bengel P, Holzamer A, Hilker M, Streckfuss-Bömeke K, Hasenfuss G, Maier LS, Sossalla S. Inhibition of Na V1.8 prevents atrial arrhythmogenesis in human and mice. Basic Res Cardiol 2020; 115:20. [PMID: 32078054 PMCID: PMC7033079 DOI: 10.1007/s00395-020-0780-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Accepted: 02/10/2020] [Indexed: 12/19/2022]
Abstract
Pharmacologic approaches for the treatment of atrial arrhythmias are limited due to side effects and low efficacy. Thus, the identification of new antiarrhythmic targets is of clinical interest. Recent genome studies suggested an involvement of SCN10A sodium channels (NaV1.8) in atrial electrophysiology. This study investigated the role and involvement of NaV1.8 (SCN10A) in arrhythmia generation in the human atria and in mice lacking NaV1.8. NaV1.8 mRNA and protein were detected in human atrial myocardium at a significant higher level compared to ventricular myocardium. Expression of NaV1.8 and NaV1.5 did not differ between myocardium from patients with atrial fibrillation and sinus rhythm. To determine the electrophysiological role of NaV1.8, we investigated isolated human atrial cardiomyocytes from patients with sinus rhythm stimulated with isoproterenol. Inhibition of NaV1.8 by A-803467 or PF-01247324 showed no effects on the human atrial action potential. However, we found that NaV1.8 significantly contributes to late Na+ current and consequently to an increased proarrhythmogenic diastolic sarcoplasmic reticulum Ca2+ leak in human atrial cardiomyocytes. Selective pharmacological inhibition of NaV1.8 potently reduced late Na+ current, proarrhythmic diastolic Ca2+ release, delayed afterdepolarizations as well as spontaneous action potentials. These findings could be confirmed in murine atrial cardiomyocytes from wild-type mice and also compared to SCN10A-/- mice (genetic ablation of NaV1.8). Pharmacological NaV1.8 inhibition showed no effects in SCN10A-/- mice. Importantly, in vivo experiments in SCN10A-/- mice showed that genetic ablation of NaV1.8 protects against atrial fibrillation induction. This study demonstrates that NaV1.8 is expressed in the murine and human atria and contributes to late Na+ current generation and cellular arrhythmogenesis. Blocking NaV1.8 selectively counteracts this pathomechanism and protects against atrial arrhythmias. Thus, our translational study reveals a new selective therapeutic target for treating atrial arrhythmias.
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Affiliation(s)
- Steffen Pabel
- Department of Internal Medicine II, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
| | - Shakil Ahmad
- Department of Internal Medicine II, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
- Clinic for Cardiology and Pneumology, Georg-August University Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany
| | - Petros Tirilomis
- Clinic for Cardiology and Pneumology, Georg-August University Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany
| | - Thea Stehle
- Department of Internal Medicine II, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
| | - Julian Mustroph
- Department of Internal Medicine II, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
| | - Maria Knierim
- Clinic for Cardiology and Pneumology, Georg-August University Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany
| | - Nataliya Dybkova
- Clinic for Cardiology and Pneumology, Georg-August University Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany
| | - Philipp Bengel
- Clinic for Cardiology and Pneumology, Georg-August University Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany
| | - Andreas Holzamer
- Department of Cardiothoracic Surgery, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
| | - Michael Hilker
- Department of Cardiothoracic Surgery, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
| | - Katrin Streckfuss-Bömeke
- Clinic for Cardiology and Pneumology, Georg-August University Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany
| | - Gerd Hasenfuss
- Clinic for Cardiology and Pneumology, Georg-August University Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany
| | - Lars S Maier
- Department of Internal Medicine II, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
| | - Samuel Sossalla
- Department of Internal Medicine II, University Medical Center Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany.
- Clinic for Cardiology and Pneumology, Georg-August University Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany.
- DZHK (German Centre for Cardiovascular Research), Partner Site Göttingen, Robert Koch Str. 40, 37075, Göttingen, Germany.
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26
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Oldfield CJ, Duhamel TA, Dhalla NS. Mechanisms for the transition from physiological to pathological cardiac hypertrophy. Can J Physiol Pharmacol 2020; 98:74-84. [DOI: 10.1139/cjpp-2019-0566] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The heart is capable of responding to stressful situations by increasing muscle mass, which is broadly defined as cardiac hypertrophy. This phenomenon minimizes ventricular wall stress for the heart undergoing a greater than normal workload. At initial stages, cardiac hypertrophy is associated with normal or enhanced cardiac function and is considered to be adaptive or physiological; however, at later stages, if the stimulus is not removed, it is associated with contractile dysfunction and is termed as pathological cardiac hypertrophy. It is during physiological cardiac hypertrophy where the function of subcellular organelles, including the sarcolemma, sarcoplasmic reticulum, mitochondria, and myofibrils, may be upregulated, while pathological cardiac hypertrophy is associated with downregulation of these subcellular activities. The transition of physiological cardiac hypertrophy to pathological cardiac hypertrophy may be due to the reduction in blood supply to hypertrophied myocardium as a consequence of reduced capillary density. Oxidative stress, inflammatory processes, Ca2+-handling abnormalities, and apoptosis in cardiomyocytes are suggested to play a critical role in the depression of contractile function during the development of pathological hypertrophy.
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Affiliation(s)
- Christopher J. Oldfield
- Faculty of Kinesiology & Recreation Management, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, MB R2H 2A6, Canada
| | - Todd A. Duhamel
- Faculty of Kinesiology & Recreation Management, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, MB R2H 2A6, Canada
| | - Naranjan S. Dhalla
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, MB R2H 2A6, Canada
- Department of Physiology & Pathophysiology, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada
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Abi-Gerges N, Miller PE, Ghetti A. Human Heart Cardiomyocytes in Drug Discovery and Research: New Opportunities in Translational Sciences. Curr Pharm Biotechnol 2019; 21:787-806. [PMID: 31820682 DOI: 10.2174/1389201021666191210142023] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 10/14/2019] [Accepted: 10/28/2019] [Indexed: 12/28/2022]
Abstract
In preclinical drug development, accurate prediction of drug effects on the human heart is critically important, whether in the context of cardiovascular safety or for the purpose of modulating cardiac function to treat heart disease. Current strategies have significant limitations, whereby, cardiotoxic drugs can escape detection or potential life-saving therapies are abandoned due to false positive toxicity signals. Thus, new and more reliable translational approaches are urgently needed to help accelerate the rate of new therapy development. Renewed efforts in the recovery of human donor hearts for research and in cardiomyocyte isolation methods, are providing new opportunities for preclinical studies in adult primary cardiomyocytes. These cells exhibit the native physiological and pharmacological properties, overcoming the limitations presented by artificial cellular models, animal models and have great potential for providing an excellent tool for preclinical drug testing. Adult human primary cardiomyocytes have already shown utility in assessing drug-induced cardiotoxicity risk and helping in the identification of new treatments for cardiac diseases, such as heart failure and atrial fibrillation. Finally, strategies with actionable decision-making trees that rely on data derived from adult human primary cardiomyocytes will provide the holistic insights necessary to accurately predict human heart effects of drugs.
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Affiliation(s)
- Najah Abi-Gerges
- AnaBios Corporation, 3030 Bunker Hill St., Suite 312, San Diego, CA 92109, United States
| | - Paul E Miller
- AnaBios Corporation, 3030 Bunker Hill St., Suite 312, San Diego, CA 92109, United States
| | - Andre Ghetti
- AnaBios Corporation, 3030 Bunker Hill St., Suite 312, San Diego, CA 92109, United States
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28
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Greer-Short A, Musa H, Alsina KM, Ni L, Word TA, Reynolds JO, Gratz D, Lane C, El-Refaey M, Unudurthi S, Skaf M, Li N, Fedorov VV, Wehrens XHT, Mohler PJ, Hund TJ. Calmodulin kinase II regulates atrial myocyte late sodium current, calcium handling, and atrial arrhythmia. Heart Rhythm 2019; 17:503-511. [PMID: 31622781 DOI: 10.1016/j.hrthm.2019.10.016] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Indexed: 12/19/2022]
Abstract
BACKGROUND Atrial fibrillation (AF) is the most common type of arrhythmia. Abnormal atrial myocyte Ca2+ handling promotes aberrant membrane excitability and remodeling that are important for atrial arrhythmogenesis. The sequence of molecular events leading to loss of normal atrial myocyte Ca2+ homeostasis is not established. Late Na+ current (INa,L) is increased in atrial myocytes from AF patients together with an increase in activity of Ca2+/calmodulin-dependent kinase II (CaMKII). OBJECTIVE The purpose of this study was to determine whether CaMKII-dependent phosphorylation at Ser571 on NaV1.5 increases atrial INa,L, leading to aberrant atrial Ca2+ cycling, altered electrophysiology, and increased AF risk. METHODS Atrial myocyte electrophysiology, Ca2+ handling, and arrhythmia susceptibility were studied in wild-type and Scn5a knock-in mice expressing phosphomimetic (S571E) or phosphoresistant (S571A) NaV1.5 at Ser571. RESULTS Atrial myocytes from S571E but not S571A mice displayed an increase in INa,L and action potential duration, and with adrenergic stress have increased delayed afterdepolarizations. Frequency of Ca2+ sparks and waves was increased in S571E atrial myocytes compared to wild type. S571E mice showed an increase in atrial events induced by adrenergic stress and AF inducibility in vivo. Isolated S571E atria were more susceptible to spontaneous atrial events, which were abrogated by inhibiting sarcoplasmic reticulum Ca2+ release, CaMKII, or the Na+/Ca2+ exchanger. Expression of phospho-NaV1.5 at Ser571 and autophosphorylated CaMKII were increased in atrial samples from human AF patients. CONCLUSION This study identified CaMKII-dependent regulation of NaV1.5 as an important upstream event in Ca2+ handling defects and abnormal impulse generation in the setting of AF.
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Affiliation(s)
- Amara Greer-Short
- The Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio; Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, Ohio
| | - Hassan Musa
- The Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio
| | - Katherina M Alsina
- Cardiovascular Research Institute, Departments of Molecular Physiology & Biophysics, Medicine (Cardiology), Pediatrics (Cardiology), and Neuroscience, Center for Space Medicine, Baylor College of Medicine, Houston, Texas
| | - Li Ni
- Cardiovascular Research Institute, Departments of Molecular Physiology & Biophysics, Medicine (Cardiology), Pediatrics (Cardiology), and Neuroscience, Center for Space Medicine, Baylor College of Medicine, Houston, Texas
| | - Tarah A Word
- Cardiovascular Research Institute, Departments of Molecular Physiology & Biophysics, Medicine (Cardiology), Pediatrics (Cardiology), and Neuroscience, Center for Space Medicine, Baylor College of Medicine, Houston, Texas
| | - Julia O Reynolds
- Cardiovascular Research Institute, Departments of Molecular Physiology & Biophysics, Medicine (Cardiology), Pediatrics (Cardiology), and Neuroscience, Center for Space Medicine, Baylor College of Medicine, Houston, Texas
| | - Daniel Gratz
- The Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio; Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, Ohio
| | - Cemantha Lane
- The Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio; Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, Ohio
| | - Mona El-Refaey
- The Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio
| | - Sathya Unudurthi
- The Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio; Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, Ohio
| | - Michel Skaf
- The Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio
| | - Ning Li
- The Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio; Department of Physiology & Cell Biology, The Ohio State University College of Medicine, Columbus, Ohio
| | - Vadim V Fedorov
- The Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio; Department of Physiology & Cell Biology, The Ohio State University College of Medicine, Columbus, Ohio
| | - Xander H T Wehrens
- Cardiovascular Research Institute, Departments of Molecular Physiology & Biophysics, Medicine (Cardiology), Pediatrics (Cardiology), and Neuroscience, Center for Space Medicine, Baylor College of Medicine, Houston, Texas
| | - Peter J Mohler
- The Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio; Department of Physiology & Cell Biology, The Ohio State University College of Medicine, Columbus, Ohio; Department of Internal Medicine, The Ohio State University College of Medicine, Columbus, Ohio
| | - Thomas J Hund
- The Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio; Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, Ohio; Department of Internal Medicine, The Ohio State University College of Medicine, Columbus, Ohio.
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29
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CaMKII Activity in the Inflammatory Response of Cardiac Diseases. Int J Mol Sci 2019; 20:ijms20184374. [PMID: 31489895 PMCID: PMC6770001 DOI: 10.3390/ijms20184374] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 09/02/2019] [Accepted: 09/03/2019] [Indexed: 12/20/2022] Open
Abstract
Inflammation is a physiological process by which the body responds to external insults and stress conditions, and it is characterized by the production of pro-inflammatory mediators such as cytokines. The acute inflammatory response is solved by removing the threat. Conversely, a chronic inflammatory state is established due to a prolonged inflammatory response and may lead to tissue damage. Based on the evidence of a reciprocal regulation between inflammation process and calcium unbalance, here we described the involvement of a calcium sensor in cardiac diseases with inflammatory drift. Indeed, the Ca2+/calmodulin-dependent protein kinase II (CaMKII) is activated in several diseases with an inflammatory component, such as myocardial infarction, ischemia/reperfusion injury, pressure overload/hypertrophy, and arrhythmic syndromes, in which it actively regulates pro-inflammatory signaling, among which includes nuclear factor kappa-B (NF-κB), thus contributing to pathological cardiac remodeling. Thus, CaMKII may represent a key target to modulate the severity of the inflammatory-driven degeneration.
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30
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Zhao H, Li T, Liu G, Zhang L, Li G, Yu J, Lou Q, He R, Zhan C, Li L, Yang W, Zang Y, Cheng C, Li W. Chronic B-Type Natriuretic Peptide Therapy Prevents Atrial Electrical Remodeling in a Rabbit Model of Atrial Fibrillation. J Cardiovasc Pharmacol Ther 2019; 24:575-585. [PMID: 31159577 DOI: 10.1177/1074248419854749] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Atrial fibrillation (AF) is an important and growing clinical problem. Current pharmacological treatments are unsatisfactory. Electrical remodeling has been identified as one of the principal pathophysiological mechanisms that promote AF, but there are no effective therapies to prevent or correct electrical remodeling in patients with AF. In AF, cardiac production and circulating levels of B-type natriuretic peptide (BNP) are increased. However, its functional significance in AF remains to be determined. We assessed the hypotheses that chronic BNP treatment may prevent the altered electrophysiology in AF, and preventing AF-induced activation of Ca2+/calmodulin-dependent protein kinase II (CaMKII) may play a role. METHODS AND RESULTS Forty-four rabbits were randomly divided into sham, rapid atrial pacing (RAP at 600 beats/min for 3 weeks), RAP/BNP, and sham/BNP groups. Rabbits in the RAP/BNP and sham/BNP groups received subcutaneous BNP (20 μg/kg twice daily) during the 3-week study period. HL-1 cells were subjected to rapid field stimulation for 24 hours in the presence or absence of BNP, KN-93 (a CaMKII inhibitor), or KN-92 (a nonactive analog of KN-93). We compared atrial electrical remodeling-related alterations in the ion channel/function/expression of these animals. We found that only in the RAP group, AF inducibility was significantly increased, atrial effective refractory periods and action potential duration were reduced, and the density of I Ca, L and I to decreased, while I K1 increased. The changes in the expressions of Cav1.2, Kv4.3, and Kir2.1 and currents showed a similar trend. In addition, in the RAP group, the activation of CaMKIIδ and phosphorylation of ryanodine receptor 2 and phospholamban significantly increased. Importantly, these changes were prevented in the RAP/BNP group, which were further validated by in vitro studies. CONCLUSIONS Chronic BNP therapy prevents atrial electrical remodeling in AF. Inhibition of CaMKII activation plays an important role to its anti-AF efficacy in this model.
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Affiliation(s)
- Hongyan Zhao
- 1 Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China.,2 Department of Cardiology, The People's Hospital of Liaoning Province, Shenyang, China
| | - Tiankai Li
- 1 Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Guangzhong Liu
- 1 Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Li Zhang
- 1 Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Guangnan Li
- 1 Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Jia Yu
- 1 Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Qi Lou
- 1 Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Rui He
- 1 Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Chengchuang Zhan
- 1 Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Luyifei Li
- 1 Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Wen Yang
- 1 Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Yanxiang Zang
- 1 Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Cheping Cheng
- 1 Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China.,3 Department of Internal Medicine, Section on Cardiovascular Medicine, and Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Weimin Li
- 1 Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
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31
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Zhabyeyev P, McLean B, Chen X, Vanhaesebroeck B, Oudit GY. Inhibition of PI3Kinase-α is pro-arrhythmic and associated with enhanced late Na + current, contractility, and Ca 2+ release in murine hearts. J Mol Cell Cardiol 2019; 132:98-109. [PMID: 31095940 DOI: 10.1016/j.yjmcc.2019.05.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 04/11/2019] [Accepted: 05/09/2019] [Indexed: 12/19/2022]
Abstract
BACKGROUND Phosphoinositide 3-kinase α (PI3Kα) is a proto-oncogene with high activity in the heart. BYL719 (BYL) is a PI3Kα-selective small molecule inhibitor and a prospective drug for advanced solid tumors. We investigated whether acute pharmacological inhibition of PI3Kα has pro-arrhythmic effects. METHODS & RESULTS In isolated wild-type (WT) cardiomyocytes, pharmacological inhibition of PI3Kα (BYL719) increased contractility by 28%, Ca2+ release by 20%, and prolonged action potential (AP) repolarization by 10-15%. These effects of BYL719 were abolished by inhibition of reverse-mode Na+/Ca2+ exchanger (NCX) (KB-R7943) or by inhibition of late Na+ current (INa-L) (ranolazine). BYL719 had no effect on PI3Kα-deficient cardiomyocytes, suggesting BYL719 effects were PI3Kα-dependent and mediated via NCX and INa-L. INa-L was suppressed by activation of PI3Kα, application of exogenous intracellular PIP3, or ranolazine. Investigation of AP and Ca2+ release in whole heart preparations using epicardial optical mapping showed that inhibition of PI3Kα similarly led to prolongation of AP and enhancement of Ca2+ release. In hearts of PI3Kα-deficient mice, β-adrenergic stimulation in the presence of high Ca2+ concentrations and 12-Hz burst pacing led to delayed afterdepolarizations and ventricular fibrillation. In vivo, administration of BYL719 prolonged QT interval [QTcF (Fridericia) increased by 15%] in WT, but not in PI3Kα-deficient mice. CONCLUSIONS Pharmacological inhibition of PI3Kα is arrhythmogenic due to activation of INa-L leading to increased sarcoplasmic reticulum Ca2+ load and prolonged QT interval. Therefore, monitoring of cardiac electrical activity in patients receiving PI3K inhibitors may provide further insights into the arrhythmogenic potential of PI3Ka inhibition.
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Affiliation(s)
- Pavel Zhabyeyev
- Department of Medicine, University of Alberta, Edmonton, Canada; Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Canada
| | - Brent McLean
- Department of Medicine, University of Alberta, Edmonton, Canada; Department of Physiology, University of Alberta, Edmonton, Canada; Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Canada
| | - Xueyi Chen
- Department of Medicine, University of Alberta, Edmonton, Canada; Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Canada
| | | | - Gavin Y Oudit
- Department of Medicine, University of Alberta, Edmonton, Canada; Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Canada.
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32
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Dai W, Laforest B, Tyan L, Shen KM, Nadadur RD, Alvarado FJ, Mazurek SR, Lazarevic S, Gadek M, Wang Y, Li Y, Valdivia HH, Shen L, Broman MT, Moskowitz IP, Weber CR. A calcium transport mechanism for atrial fibrillation in Tbx5-mutant mice. eLife 2019; 8:41814. [PMID: 30896405 PMCID: PMC6428569 DOI: 10.7554/elife.41814] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 02/28/2019] [Indexed: 02/06/2023] Open
Abstract
Risk for Atrial Fibrillation (AF), the most common human arrhythmia, has a major genetic component. The T-box transcription factor TBX5 influences human AF risk, and adult-specific Tbx5-mutant mice demonstrate spontaneous AF. We report that TBX5 is critical for cellular Ca2+ homeostasis, providing a molecular mechanism underlying the genetic implication of TBX5 in AF. We show that cardiomyocyte action potential (AP) abnormalities in Tbx5-deficient atrial cardiomyocytes are caused by a decreased sarcoplasmic reticulum (SR) Ca2+ ATPase (SERCA2)-mediated SR calcium uptake which was balanced by enhanced trans-sarcolemmal calcium fluxes (calcium current and sodium/calcium exchanger), providing mechanisms for triggered activity. The AP defects, cardiomyocyte ectopy, and AF caused by TBX5 deficiency were rescued by phospholamban removal, which normalized SERCA function. These results directly link transcriptional control of SERCA2 activity, depressed SR Ca2+ sequestration, enhanced trans-sarcolemmal calcium fluxes, and AF, establishing a mechanism underlying the genetic basis for a Ca2+-dependent pathway for AF risk. The human heart contains four distinct chambers that work together to pump blood around the body. In individuals with a condition called atrial fibrillation, two of the chambers (known as the atria) beat irregularly and are unable to push all the blood they hold into the other two chambers of the heart. This can cause heart failure and increases the likelihood of blood clots, which may lead to stroke and heart attacks. Small molecules called calcium ions play a crucial role in regulating how and when the atria contract by driving electrical activity in heart cells. To contract the atria, a storage compartment within heart cells known as the sarcoplasmic reticulum releases calcium ions into the main compartment of the cells. Calcium ions also enter the cell from the surrounding tissue. As the atria relax, calcium ions are pumped back into the sarcoplasmic reticulum or out of the cell by specific transport proteins. Individuals with mutations in a gene called Tbx5 are more likely to develop atrial fibrillation than other people, but it was not clear how such gene mutations contribute to the disease. Here, Dai, Laforest et al. used mice with a mutation in the Tbx5 gene to study how defects in Tbx5 affect electrical activity in heart cells. The experiments found that the Tbx5 gene was critical for calcium ions to drive normal electrical activity in mouse heart cells. Compared with heart cells from normal mice, the heart cells from the mutant mice had decreased flow of calcium ions into the sarcoplasmic reticulum and increased flow of calcium ions out of the cell. These findings provide a direct link between atrial fibrillation and the flow of calcium ions in heart cells. Together with previous work, these findings indicate that multiple different mechanisms could lead to atrial fibrillation, but that many of these involve changes in the flow of calcium ions. Therefore, personalized medicine, where clinicians uncover the specific mechanisms responsible for atrial fibrillation in individual patients, may play an important role in treating this condition in the future.
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Affiliation(s)
- Wenli Dai
- Department of Pathology, University of Chicago, Chicago, United States
| | - Brigitte Laforest
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, United States
| | - Leonid Tyan
- Department of Pathology, University of Chicago, Chicago, United States
| | - Kaitlyn M Shen
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, United States
| | - Rangarajan D Nadadur
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, United States
| | - Francisco J Alvarado
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, United States
| | - Stefan R Mazurek
- Department of Medicine, University of Chicago, Chicago, United States
| | - Sonja Lazarevic
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, United States
| | - Margaret Gadek
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, United States
| | - Yitang Wang
- Department of Pathology, University of Chicago, Chicago, United States
| | - Ye Li
- Department of Pathology, University of Chicago, Chicago, United States
| | - Hector H Valdivia
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, United States
| | - Le Shen
- Department of Pathology, University of Chicago, Chicago, United States.,Section of Neurosurgery, Department of Surgery, University of Chicago, Chicago, United States
| | - Michael T Broman
- Department of Medicine, University of Chicago, Chicago, United States
| | - Ivan P Moskowitz
- Departments of Pediatrics, Pathology, and Human Genetics, University of Chicago, Chicago, United States
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33
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Protein kinase/phosphatase balance mediates the effects of increased late sodium current on ventricular calcium cycling. Basic Res Cardiol 2019; 114:13. [DOI: 10.1007/s00395-019-0720-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 02/12/2019] [Indexed: 12/19/2022]
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34
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Nie J, Duan Q, He M, Li X, Wang B, Zhou C, Wu L, Wen Z, Chen C, Wang DW, Alsina KM, Wehrens XHT, Wang DW, Ni L. Ranolazine prevents pressure overload-induced cardiac hypertrophy and heart failure by restoring aberrant Na + and Ca 2+ handling. J Cell Physiol 2018; 234:11587-11601. [PMID: 30488495 DOI: 10.1002/jcp.27791] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Accepted: 11/06/2018] [Indexed: 12/24/2022]
Abstract
BACKGROUND Cardiac hypertrophy and heart failure are characterized by increased late sodium current and abnormal Ca2+ handling. Ranolazine, a selective inhibitor of the late sodium current, can reduce sodium accumulation and Ca 2+ overload. In this study, we investigated the effects of ranolazine on pressure overload-induced cardiac hypertrophy and heart failure in mice. METHODS AND RESULTS Inhibition of late sodium current with the selective inhibitor ranolazine suppressed cardiac hypertrophy and fibrosis and improved heart function assessed by echocardiography, hemodynamics, and histological analysis in mice exposed to chronic pressure overload induced by transverse aortic constriction (TAC). Ca2+ imaging of ventricular myocytes from TAC mice revealed both abnormal SR Ca 2+ release and increased SR Ca 2+ leak. Ranolazine restored aberrant SR Ca 2+ handling induced by pressure overload. Ranolazine also suppressed Na + overload induced in the failing heart, and restored Na + -induced Ca 2+ overload in an sodium-calcium exchanger (NCX)-dependent manner. Ranolazine suppressed the Ca 2+ -dependent calmodulin (CaM)/CaMKII/myocyte enhancer factor-2 (MEF2) and CaM/CaMKII/calcineurin/nuclear factor of activated T-cells (NFAT) hypertrophy signaling pathways triggered by pressure overload. Pressure overload also prolonged endoplasmic reticulum (ER) stress leading to ER-initiated apoptosis, while inhibition of late sodium current or NCX relieved ER stress and ER-initiated cardiomyocyte apoptosis. CONCLUSIONS Our study demonstrates that inhibition of late sodium current with ranolazine improves pressure overload-induced cardiac hypertrophy and systolic and diastolic function by restoring Na+ and Ca 2+ handling, inhibiting the downstream hypertrophic pathways and ER stress. Inhibition of late sodium current may provide a new treatment strategy for cardiac hypertrophy and heart failure.
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Affiliation(s)
- Jiali Nie
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan, China
| | - Quanlu Duan
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan, China
| | - Mengying He
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan, China
| | - Xianqing Li
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan, China
| | - Bei Wang
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan, China
| | - Chi Zhou
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan, China
| | - Lujin Wu
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan, China
| | - Zheng Wen
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan, China
| | - Chen Chen
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan, China
| | - Dao Wu Wang
- Department of Cardiology, The First Affiliated Hospital, Nanjing Medical University, Nanjing, China
| | - Katherina M Alsina
- Department of Molecular Physiology & Biophysics and Department of Medicine, Cardiovascular Research Institute, Cardiology Baylor College of Medicine, Houston, Texas
| | - Xander H T Wehrens
- Department of Molecular Physiology & Biophysics and Department of Medicine, Cardiovascular Research Institute, Cardiology Baylor College of Medicine, Houston, Texas
| | - Dao Wen Wang
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan, China
| | - Li Ni
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan, China.,Department of Molecular Physiology & Biophysics and Department of Medicine, Cardiovascular Research Institute, Cardiology Baylor College of Medicine, Houston, Texas
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35
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Yoo S, Aistrup G, Shiferaw Y, Ng J, Mohler PJ, Hund TJ, Waugh T, Browne S, Gussak G, Gilani M, Knight BP, Passman R, Goldberger JJ, Wasserstrom JA, Arora R. Oxidative stress creates a unique, CaMKII-mediated substrate for atrial fibrillation in heart failure. JCI Insight 2018; 3:120728. [PMID: 30385719 DOI: 10.1172/jci.insight.120728] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 09/27/2018] [Indexed: 12/31/2022] Open
Abstract
The precise mechanisms by which oxidative stress (OS) causes atrial fibrillation (AF) are not known. Since AF frequently originates in the posterior left atrium (PLA), we hypothesized that OS, via calmodulin-dependent protein kinase II (CaMKII) signaling, creates a fertile substrate in the PLA for triggered activity and reentry. In a canine heart failure (HF) model, OS generation and oxidized-CaMKII-induced (Ox-CaMKII-induced) RyR2 and Nav1.5 signaling were increased preferentially in the PLA (compared with left atrial appendage). Triggered Ca2+ waves (TCWs) in HF PLA myocytes were particularly sensitive to acute ROS inhibition. Computational modeling confirmed a direct relationship between OS/CaMKII signaling and TCW generation. CaMKII phosphorylated Nav1.5 (CaMKII-p-Nav1.5 [S571]) was located preferentially at the intercalated disc (ID), being nearly absent at the lateral membrane. Furthermore, a decrease in ankyrin-G (AnkG) in HF led to patchy dropout of CaMKII-p-Nav1.5 at the ID, causing its distribution to become spatially heterogeneous; this corresponded to preferential slowing and inhomogeneity of conduction noted in the HF PLA. Computational modeling illustrated how conduction slowing (e.g., due to increase in CaMKII-p-Nav1.5) interacts with fibrosis to cause reentry in the PLA. We conclude that OS via CaMKII leads to substrate for triggered activity and reentry in HF PLA by mechanisms independent of but complementary to fibrosis.
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Affiliation(s)
- Shin Yoo
- Feinberg Cardiovascular Research and Renal Institute, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Gary Aistrup
- Feinberg Cardiovascular Research and Renal Institute, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Yohannes Shiferaw
- Department of Physics, California State University, Northridge, California, USA
| | - Jason Ng
- Feinberg Cardiovascular Research and Renal Institute, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Peter J Mohler
- Dorothy M. Davis Heart and Lung Research Institute, Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Thomas J Hund
- Dorothy M. Davis Heart and Lung Research Institute, Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Trent Waugh
- Feinberg Cardiovascular Research and Renal Institute, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Suzanne Browne
- Feinberg Cardiovascular Research and Renal Institute, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Georg Gussak
- Feinberg Cardiovascular Research and Renal Institute, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Mehul Gilani
- Feinberg Cardiovascular Research and Renal Institute, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Bradley P Knight
- Feinberg Cardiovascular Research and Renal Institute, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Rod Passman
- Feinberg Cardiovascular Research and Renal Institute, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Jeffrey J Goldberger
- Feinberg Cardiovascular Research and Renal Institute, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - J Andrew Wasserstrom
- Feinberg Cardiovascular Research and Renal Institute, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Rishi Arora
- Feinberg Cardiovascular Research and Renal Institute, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
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36
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Ahmad S, Tirilomis P, Pabel S, Dybkova N, Hartmann N, Molina CE, Tirilomis T, Kutschka I, Frey N, Maier LS, Hasenfuss G, Streckfuss-Bömeke K, Sossalla S. The functional consequences of sodium channel Na V 1.8 in human left ventricular hypertrophy. ESC Heart Fail 2018; 6:154-163. [PMID: 30378291 PMCID: PMC6352890 DOI: 10.1002/ehf2.12378] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 09/18/2018] [Accepted: 10/10/2018] [Indexed: 01/15/2023] Open
Abstract
Aims In hypertrophy and heart failure, the proarrhythmic persistent Na+ current (INaL) is enhanced. We aimed to investigate the electrophysiological role of neuronal sodium channel NaV1.8 in human hypertrophied myocardium. Methods and results Myocardial tissue of 24 patients suffering from symptomatic severe aortic stenosis and concomitant significant afterload‐induced hypertrophy with preserved ejection fraction was used and compared with 12 healthy controls. We performed quantitative real‐time PCR and western blot and detected a significant up‐regulation of NaV1.8 mRNA (2.34‐fold) and protein expression (1.96‐fold) in human hypertrophied myocardium compared with healthy hearts. Interestingly, NaV1.5 protein expression was significantly reduced in parallel (0.60‐fold). Using whole‐cell patch‐clamp technique, we found that the prominent INaL was significantly reduced after addition of novel NaV1.8‐specific blockers either A‐803467 (30 nM) or PF‐01247324 (1 μM) in human hypertrophic cardiomyocytes. This clearly demonstrates the relevant contribution of NaV1.8 to this proarrhythmic current. We observed a significant action potential duration shortening and performed confocal microscopy, demonstrating a 50% decrease in proarrhythmic diastolic sarcoplasmic reticulum (SR)‐Ca2+ leak and SR‐Ca2+ spark frequency after exposure to both NaV1.8 inhibitors. Conclusions We show for the first time that the neuronal sodium channel NaV1.8 is up‐regulated on mRNA and protein level in the human hypertrophied myocardium. Furthermore, inhibition of NaV1.8 reduced augmented INaL, abbreviated the action potential duration, and decreased the SR‐Ca2+ leak. The findings of our study suggest that NaV1.8 could be a promising antiarrhythmic therapeutic target and merits further investigation.
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Affiliation(s)
- Shakil Ahmad
- Department of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany.,Department of Cardiology and Pneumology, University Hospital, Georg-August University Goettingen, and DZHK (German Centre for Cardiovascular Research), partner site Goettingen, Goettingen, Germany
| | - Petros Tirilomis
- Department of Cardiology and Pneumology, University Hospital, Georg-August University Goettingen, and DZHK (German Centre for Cardiovascular Research), partner site Goettingen, Goettingen, Germany
| | - Steffen Pabel
- Department of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany
| | - Nataliya Dybkova
- Department of Cardiology and Pneumology, University Hospital, Georg-August University Goettingen, and DZHK (German Centre for Cardiovascular Research), partner site Goettingen, Goettingen, Germany
| | - Nico Hartmann
- Department of Cardiology and Pneumology, University Hospital, Georg-August University Goettingen, and DZHK (German Centre for Cardiovascular Research), partner site Goettingen, Goettingen, Germany
| | - Cristina E Molina
- Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Theodoros Tirilomis
- Department of Thoracic, Cardiac and Vascular Surgery, University Hospital, Georg-August University Goettingen, Goettingen, Germany
| | - Ingo Kutschka
- Department of Thoracic, Cardiac and Vascular Surgery, University Hospital, Georg-August University Goettingen, Goettingen, Germany
| | - Norbert Frey
- Department of Internal Medicine III, Molecular Cardiology and Angiology, University Medical Center, Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Lars S Maier
- Department of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany
| | - Gerd Hasenfuss
- Department of Cardiology and Pneumology, University Hospital, Georg-August University Goettingen, and DZHK (German Centre for Cardiovascular Research), partner site Goettingen, Goettingen, Germany
| | - Katrin Streckfuss-Bömeke
- Department of Cardiology and Pneumology, University Hospital, Georg-August University Goettingen, and DZHK (German Centre for Cardiovascular Research), partner site Goettingen, Goettingen, Germany
| | - Samuel Sossalla
- Department of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany.,Department of Cardiology and Pneumology, University Hospital, Georg-August University Goettingen, and DZHK (German Centre for Cardiovascular Research), partner site Goettingen, Goettingen, Germany
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37
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Arrhythmias precede cardiomyopathy and remodeling of Ca2+ handling proteins in a novel model of long QT syndrome. J Mol Cell Cardiol 2018; 123:13-25. [DOI: 10.1016/j.yjmcc.2018.08.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 07/03/2018] [Accepted: 08/21/2018] [Indexed: 01/13/2023]
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Mohamed BA, Hartmann N, Tirilomis P, Sekeres K, Li W, Neef S, Richter C, Zeisberg EM, Kattner L, Didié M, Guan K, Schmitto JD, Lehnart SE, Luther S, Voigt N, Seidler T, Sossalla S, Hasenfuss G, Toischer K. Sarcoplasmic reticulum calcium leak contributes to arrhythmia but not to heart failure progression. Sci Transl Med 2018; 10:10/458/eaan0724. [DOI: 10.1126/scitranslmed.aan0724] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 01/30/2018] [Accepted: 08/09/2018] [Indexed: 12/30/2022]
Abstract
Increased sarcoplasmic reticulum (SR) Ca2+ leak via the cardiac ryanodine receptor (RyR2) has been suggested to play a mechanistic role in the development of heart failure (HF) and cardiac arrhythmia. Mice treated with a selective RyR2 stabilizer, rycal S36, showed normalization of SR Ca2+ leak and improved survival in pressure overload (PO) and myocardial infarction (MI) models. The development of HF, measured by echocardiography and molecular markers, showed no difference in rycal S36– versus placebo-treated mice. Reduction of SR Ca2+ leak in the PO model by the rycal-unrelated RyR2 stabilizer dantrolene did not mitigate HF progression. Development of HF was not aggravated by increased SR Ca2+ leak due to RyR2 mutation (R2474S) in volume overload, an SR Ca2+ leak–independent HF model. Arrhythmia episodes were reduced by rycal S36 treatment in PO and MI mice in vivo and ex vivo in Langendorff-perfused hearts. Isolated cardiomyocytes from murine failing hearts and human ventricular failing and atrial nonfailing myocardium showed reductions in delayed afterdepolarizations, in spontaneous and induced Ca2+ waves, and in triggered activity in rycal S36 versus placebo cells, whereas the Ca2+ transient, SR Ca2+ load, SR Ca2+ adenosine triphosphatase function, and action potential duration were not affected. Rycal S36 treatment of human induced pluripotent stem cells isolated from a patient with catecholaminergic polymorphic ventricular tachycardia could rescue the leaky RyR2 receptor. These results suggest that SR Ca2+ leak does not primarily influence contractile HF progression, whereas rycal S36 treatment markedly reduces ventricular arrhythmias, thereby improving survival in mice.
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Affiliation(s)
- Belal A. Mohamed
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
- Department of Medical Biochemistry and Molecular Biology, Faculty of Medicine, Mansoura University, Mansoura City 35516, Egypt
| | - Nico Hartmann
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
| | - Petros Tirilomis
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
| | - Karolina Sekeres
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- Institute of Pharmacology and Toxicology, Technische Universität Dresden, 01307 Dresden, Germany
| | - Wener Li
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- Institute of Pharmacology and Toxicology, Technische Universität Dresden, 01307 Dresden, Germany
| | - Stefan Neef
- Department of Internal Medicine II, University Hospital Regensburg, 93053 Regensburg, Germany
| | - Claudia Richter
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
- Research Group Biomedical Physics, Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
| | - Elisabeth M. Zeisberg
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
| | - Lars Kattner
- Endotherm Life Science Molecules, 66123 Saarbrücken, Germany
| | - Michael Didié
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
- Institute of Pharmacology and Toxicology, Georg-August-University, 37075 Göttingen, Germany
| | - Kaomei Guan
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- Institute of Pharmacology and Toxicology, Technische Universität Dresden, 01307 Dresden, Germany
| | - Jan D. Schmitto
- Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, 30625 Hannover, Germany
| | - Stephan E. Lehnart
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
- BioMET, Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Stefan Luther
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
- Research Group Biomedical Physics, Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
- Institute of Pharmacology and Toxicology, Georg-August-University, 37075 Göttingen, Germany
| | - Niels Voigt
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
- Institute of Pharmacology and Toxicology, Georg-August-University, 37075 Göttingen, Germany
| | - Tim Seidler
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
| | - Samuel Sossalla
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
- Department of Internal Medicine II, University Hospital Regensburg, 93053 Regensburg, Germany
| | - Gerd Hasenfuss
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
| | - Karl Toischer
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
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Mustroph J, Wagemann O, Lebek S, Tarnowski D, Ackermann J, Drzymalski M, Pabel S, Schmid C, Wagner S, Sossalla S, Maier LS, Neef S. SR Ca 2+-leak and disordered excitation-contraction coupling as the basis for arrhythmogenic and negative inotropic effects of acute ethanol exposure. J Mol Cell Cardiol 2018; 116:81-90. [PMID: 29410242 DOI: 10.1016/j.yjmcc.2018.02.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 01/23/2018] [Accepted: 02/01/2018] [Indexed: 02/03/2023]
Abstract
AIMS Ethanol has acute negative inotropic and arrhythmogenic effects. The underlying mechanisms, however, are largely unknown. Sarcoplasmic reticulum Ca2+-leak is an important mechanism for reduced contractility and arrhythmias. Ca2+-leak can be induced by oxidative stress and Ca2+/Calmodulin-dependent protein kinase II (CaMKII). Therefore, we investigated the influence of acute ethanol exposure on excitation-contraction coupling in atrial and ventricular cardiomyocytes. METHODS AND RESULTS Isolated human atrial and murine atrial or ventricular cardiomyocytes were preincubated for 30 min and then superfused with control solution or solution containing ethanol. Ethanol had acute negative inotropic and positive lusitropic effects in human atrial muscle strips and murine ventricular cardiomyocytes. Accordingly, Ca2+-imaging indicated lower Ca2+-transient amplitudes and increased SERCA2a activity, while myofilament Ca2+-sensitivity was reduced. SR Ca2+-leak was assessed by measuring Ca2+-sparks. Ethanol induced severe SR Ca2+-leak in human atrial cardiomyocytes (calculated leak: 4.60 ± 0.45 mF/F0 vs 1.86 ± 0.26 in control, n ≥ 80). This effect was dose-dependent, while spontaneous arrhythmogenic Ca2+-waves increased ~5-fold, as investigated in murine cardiomyocytes. Delayed afterdepolarizations, which can result from increased SR Ca2+-leak, were significantly increased by ethanol. Measurements using the reactive oxygen species (ROS) sensor CM-H2DCFDA showed increased ROS-stress in ethanol treated cells. ROS-scavenging with N-acetylcysteine prevented negative inotropic and positive lusitropic effects in human muscle strips. Ethanol-induced Ca2+-leak was abolished in mice with knockout of NOX2 (the main source for ROS in cardiomyocytes). Importantly, mice with oxidation-resistant CaMKII (Met281/282Val mutation) were protected from ethanol-induced Ca2+-leak. CONCLUSION We show for the first time that ethanol acutely induces strong SR Ca2+-leak, also altering excitation-contraction coupling. Acute negative inotropic effects of ethanol can be explained by reduced systolic Ca2+-release. Mechanistically, ROS-production via NOX2 and oxidative activation of CaMKII appear to play central roles. This provides a mechanism for the arrhythmogenic and negative inotropic effects of ethanol and suggests a druggable target (CaMKII).
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Affiliation(s)
- Julian Mustroph
- Dept. of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany
| | - Olivia Wagemann
- Dept. of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany
| | - Simon Lebek
- Dept. of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany
| | - Daniel Tarnowski
- Dept. of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany
| | - Jasmin Ackermann
- Dept. of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany
| | - Marzena Drzymalski
- Dept. of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany
| | - Steffen Pabel
- Dept. of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany
| | - Christof Schmid
- Dept. of Cardiothoracic Surgery, University Medical Center Regensburg, Regensburg, Germany
| | - Stefan Wagner
- Dept. of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany
| | - Samuel Sossalla
- Dept. of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany
| | - Lars S Maier
- Dept. of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany
| | - Stefan Neef
- Dept. of Internal Medicine II, University Medical Center Regensburg, Regensburg, Germany.
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40
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Francois AA, Obasanjo-Blackshire K, Clark JE, Boguslavskyi A, Holt MR, Parker PJ, Marber MS, Heads RJ. Loss of Protein Kinase Novel 1 (PKN1) is associated with mild systolic and diastolic contractile dysfunction, increased phospholamban Thr17 phosphorylation, and exacerbated ischaemia-reperfusion injury. Cardiovasc Res 2018; 114:138-157. [PMID: 29045568 PMCID: PMC5815577 DOI: 10.1093/cvr/cvx206] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 03/17/2017] [Accepted: 10/13/2017] [Indexed: 01/20/2023] Open
Abstract
Aims PKN1 is a stress-responsive protein kinase acting downstream of small GTP-binding proteins of the Rho/Rac family. The aim was to determine its role in endogenous cardioprotection. Methods and results Hearts from PKN1 knockout (KO) or wild type (WT) littermate control mice were perfused in Langendorff mode and subjected to global ischaemia and reperfusion (I/R). Myocardial infarct size was doubled in PKN1 KO hearts compared to WT hearts. PKN1 was basally phosphorylated on the activation loop Thr778 PDK1 target site which was unchanged during I/R. However, phosphorylation of p42/p44-MAPK was decreased in KO hearts at baseline and during I/R. In cultured neonatal rat ventricular cardiomyocytes (NRVM) and NRVM transduced with kinase dead (KD) PKN1 K644R mutant subjected to simulated ischaemia/reperfusion (sI/R), PhosTag® gel analysis showed net dephosphorylation of PKN1 during sI and early R despite Thr778 phosphorylation. siRNA knockdown of PKN1 in NRVM significantly decreased cell survival and increased cell injury by sI/R which was reversed by WT- or KD-PKN1 expression. Confocal immunofluorescence analysis of PKN1 in NRVM showed increased localization to the sarcoplasmic reticulum (SR) during sI. GC-MS/MS and immunoblot analysis of PKN1 immunoprecipitates following sI/R confirmed interaction with CamKIIδ. Co-translocation of PKN1 and CamKIIδ to the SR/membrane fraction during sI correlated with phospholamban (PLB) Thr17 phosphorylation. siRNA knockdown of PKN1 in NRVM resulted in increased basal CamKIIδ activation and increased PLB Thr17 phosphorylation only during sI. In vivo PLB Thr17 phosphorylation, Sarco-Endoplasmic Reticulum Ca2+ ATPase (SERCA2) expression and Junctophilin-2 (Jph2) expression were also basally increased in PKN1 KO hearts. Furthermore, in vivo P-V loop analysis of the beat-to-beat relationship between rate of LV pressure development or relaxation and end diastolic P (EDP) showed mild but significant systolic and diastolic dysfunction with preserved ejection fraction in PKN1 KO hearts. Conclusion Loss of PKN1 in vivo significantly reduces endogenous cardioprotection and increases myocardial infarct size following I/R injury. Cardioprotection by PKN1 is associated with reduced CamKIIδ-dependent PLB Thr17 phosphorylation at the SR and therefore may stabilize the coupling of SR Ca2+ handling and contractile function, independent of its kinase activity.
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Affiliation(s)
- Asvi A Francois
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - Kofo Obasanjo-Blackshire
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - James E Clark
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - Andrii Boguslavskyi
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - Mark R Holt
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
- Randall Division of Cell and Molecular Biophysics, King’s College London, New Hunt’s House, Guy’s Hospital Campus, London, UK
| | - Peter J Parker
- Division of Cancer Studies, School of Cancer and Pharmaceutical Sciences, Faculty of Life Sciences and Medicine, King’s College London, New Hunt’s House, Guy’s Hospital Campus, London, UK
- Protein Phosphorylation Laboratory, Francis Crick Institute, Lincoln’s Inn Fields, London, UK
| | - Michael S Marber
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - Richard J Heads
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
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Grandi E, Dobrev D. Non-ion channel therapeutics for heart failure and atrial fibrillation: Are CaMKII inhibitors ready for clinical use? J Mol Cell Cardiol 2017; 121:300-303. [PMID: 29079077 DOI: 10.1016/j.yjmcc.2017.10.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 10/22/2017] [Indexed: 01/17/2023]
Abstract
The Ca2+-calmodulin dependent protein kinase II (CaMKII) is an established central mediator of electrophysiological and contractile responses to cardiac stress, and its hyper-activation in cardiac diseases has been linked to heart failure (HF) and arrhythmia. Here we summarize the evidence supporting the role of CaMKII as a critical nodal point for therapeutic intervention against HF and atrial and ventricular tachyarrhythmias. Targeting of CaMKII in heart with inhibitors possessing appropriate selectivity might represent a novel therapeutic approach for HF and arrhythmias.
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Affiliation(s)
- Eleonora Grandi
- Department of Pharmacology, University of California Davis, Davis, CA, USA.
| | - Dobromir Dobrev
- Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany.
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42
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Koopman CD, Zimmermann WH, Knöpfel T, de Boer TP. Cardiac optogenetics: using light to monitor cardiac physiology. Basic Res Cardiol 2017; 112:56. [PMID: 28861604 PMCID: PMC5579185 DOI: 10.1007/s00395-017-0645-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 08/28/2017] [Indexed: 12/12/2022]
Abstract
Our current understanding of cardiac excitation and its coupling to contraction is largely based on ex vivo studies utilising fluorescent organic dyes to assess cardiac action potentials and signal transduction. Recent advances in optogenetic sensors open exciting new possibilities for cardiac research and allow us to answer research questions that cannot be addressed using the classic organic dyes. Especially thrilling is the possibility to use optogenetic sensors to record parameters of cardiac excitation and contraction in vivo. In addition, optogenetics provide a high spatial resolution, as sensors can be coupled to motifs and targeted to specific cell types and subcellular domains of the heart. In this review, we will give a comprehensive overview of relevant optogenetic sensors, how they can be utilised in cardiac research and how they have been applied in cardiac research up to now.
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Affiliation(s)
- Charlotte D Koopman
- Department of Medical Physiology, University Medical Center Utrecht, Yalelaan 50, 3584CM, Utrecht, The Netherlands.,Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences (KNAW), University Medical Centre Utrecht, 3584CT, Utrecht, The Netherlands
| | - Wolfram H Zimmermann
- Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Göttingen, Germany.,DHZK (German Center for Cardiovascular Research), Partner Site, Göttingen, Germany
| | - Thomas Knöpfel
- Laboratory for Neuronal Circuit Dynamics, Imperial College London, London, UK.,Centre for Neurotechnology, Institute of Biomedical Engineering, Imperial College London, London, UK
| | - Teun P de Boer
- Department of Medical Physiology, University Medical Center Utrecht, Yalelaan 50, 3584CM, Utrecht, The Netherlands.
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Onal B, Gratz D, Hund TJ. Ca 2+/calmodulin-dependent kinase II-dependent regulation of atrial myocyte late Na + current, Ca 2+ cycling, and excitability: a mathematical modeling study. Am J Physiol Heart Circ Physiol 2017; 313:H1227-H1239. [PMID: 28842436 DOI: 10.1152/ajpheart.00185.2017] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Atrial fibrillation (AF) affects more than three million people per year in the United States and is associated with high morbidity and mortality. Both electrical and structural remodeling contribute to AF, but the molecular pathways underlying AF pathogenesis are not well understood. Recently, a role for Ca2+/calmodulin-dependent protein kinase II (CaMKII) in the regulation of persistent "late" Na+ current ( INa,L) has been identified. Although INa,L inhibition is emerging as a potential antiarrhythmic strategy in patients with AF, little is known about the mechanism linking INa,L to atrial arrhythmogenesis. A computational approach was used to test the hypothesis that increased CaMKII-activated INa,L in atrial myocytes disrupts Ca2+ homeostasis, promoting arrhythmogenic afterdepolarizations. Dynamic CaMKII activity and regulation of multiple downstream targets [ INa,L, L-type Ca2+ current, phospholamban, and the ryanodine receptor sarcoplasmic reticulum Ca2+-release channel (RyR2)] were incorporated into an existing well-validated computational model of the human atrial action potential. Model simulations showed that constitutive CaMKII-dependent phosphorylation of Nav1.5 and the subsequent increase in INa,L effectively disrupt intracellular atrial myocyte ion homeostasis and CaMKII signaling. Specifically, increased INa,L promotes intracellular Ca2+ overload via forward-mode Na+/Ca2+ exchange activity, which greatly increases RyR2 open probability beyond that observed for CaMKII-dependent phosphorylation of RyR2 alone. Increased INa,L promotes atrial myocyte repolarization defects (afterdepolarizations and alternans) in the setting of acute β-adrenergic stimulation. We anticipate that our modeling efforts will help identify new mechanisms for atrial NaV1.5 regulation with direct relevance for human AF. NEW & NOTEWORTHY Here, we present a novel computational model to study the effects of late Na+ current ( INa,L) in human atrial myocytes. Simulations predict that INa,L promotes intracellular accumulation of Ca2+, with subsequent dysregulation of Ca2+/calmodulin-dependent protein kinase II (CaMKII) signaling and ryanodine receptor 2-mediated Ca2+ release. Although INa,L plays a small role in regulating atrial myocyte excitability at baseline, CaMKII-dependent enhancement of the current promoted arrhythmogenic dynamics. Listen to this article's corresponding podcast at http://ajpheart.podbean.com/e/camkii-dependent-regulation-of-atrial-late-sodium-current-and-excitability/ .
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Affiliation(s)
- Birce Onal
- The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center , Columbus, Ohio.,Department of Biomedical Engineering, College of Engineering, The Ohio State University , Columbus, Ohio
| | - Daniel Gratz
- The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center , Columbus, Ohio.,Department of Biomedical Engineering, College of Engineering, The Ohio State University , Columbus, Ohio
| | - Thomas J Hund
- The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center , Columbus, Ohio.,Department of Biomedical Engineering, College of Engineering, The Ohio State University , Columbus, Ohio.,Department of Internal Medicine, The Ohio State University Wexner Medical Center , Columbus, Ohio
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Kirschner Peretz N, Segal S, Arbel-Ganon L, Ben Jehuda R, Shemer Y, Eisen B, Davoodi M, Binah O, Yaniv Y. A Method Sustaining the Bioelectric, Biophysical, and Bioenergetic Function of Cultured Rabbit Atrial Cells. Front Physiol 2017; 8:584. [PMID: 28860999 PMCID: PMC5559495 DOI: 10.3389/fphys.2017.00584] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 07/31/2017] [Indexed: 12/16/2022] Open
Abstract
Culturing atrial cells leads to a loss in their ability to be externally paced at physiological rates and to maintain their shape. We aim to develop a culture method that sustains the shape of atrial cells along with their biophysical and bioenergetic properties in response to physiological pacing. We hypothesize that adding 2,3-Butanedione 2-monoxime (BDM), which inhibits contraction during the culture period, will preserve these biophysical and bioenergetic properties. Rabbit atrial cells were maintained in culture for 24 h in a medium enriched with a myofilament contraction inhibitor, BDM. The morphology and volume of the cells, including their ability to contract in response to 1–3 Hz electrical pacing, was maintained at the same level as fresh cells. Importantly, the cells could be successfully infected with a GFP adenovirus. Action potentials, Ca2+ transients, and local Ca2+ spark parameters were similar in the cultured and in fresh cells. Finally, these cultured cells' flavoprotein autofluorescence was maintained at a constant level in response to electrical pacing, a response similar to that of fresh cells. Thus, eliminating contraction during the culture period preserves the bioelectric, biophysical and bioenergetic properties of rabbit atrial myocytes. This method therefore has the potential to further improve our understanding of energetic and biochemical regulation in the atria.
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Affiliation(s)
- Noa Kirschner Peretz
- Biomedical Engineering Faculty, Technion - Israel Institute of TechnologyHaifa, Israel
| | - Sofia Segal
- Biomedical Engineering Faculty, Technion - Israel Institute of TechnologyHaifa, Israel
| | - Limor Arbel-Ganon
- Biomedical Engineering Faculty, Technion - Israel Institute of TechnologyHaifa, Israel
| | - Ronen Ben Jehuda
- Department of Physiology, Biophysics and Systems Biology, Technion - Israel Institute of TechnologyHaifa, Israel.,The Rappaport Institute, The Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of TechnologyHaifa, Israel
| | - Yuval Shemer
- Department of Physiology, Biophysics and Systems Biology, Technion - Israel Institute of TechnologyHaifa, Israel.,The Rappaport Institute, The Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of TechnologyHaifa, Israel
| | - Binyamin Eisen
- Department of Physiology, Biophysics and Systems Biology, Technion - Israel Institute of TechnologyHaifa, Israel.,The Rappaport Institute, The Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of TechnologyHaifa, Israel
| | - Moran Davoodi
- Biomedical Engineering Faculty, Technion - Israel Institute of TechnologyHaifa, Israel
| | - Ofer Binah
- Department of Physiology, Biophysics and Systems Biology, Technion - Israel Institute of TechnologyHaifa, Israel.,The Rappaport Institute, The Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of TechnologyHaifa, Israel
| | - Yael Yaniv
- Biomedical Engineering Faculty, Technion - Israel Institute of TechnologyHaifa, Israel
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Abstract
There has been a significant progress in our understanding of the molecular mechanisms by which calcium (Ca2+) ions mediate various types of cardiac arrhythmias. A growing list of inherited gene defects can cause potentially lethal cardiac arrhythmia syndromes, including catecholaminergic polymorphic ventricular tachycardia, congenital long QT syndrome, and hypertrophic cardiomyopathy. In addition, acquired deficits of multiple Ca2+-handling proteins can contribute to the pathogenesis of arrhythmias in patients with various types of heart disease. In this review article, we will first review the key role of Ca2+ in normal cardiac function-in particular, excitation-contraction coupling and normal electric rhythms. The functional involvement of Ca2+ in distinct arrhythmia mechanisms will be discussed, followed by various inherited arrhythmia syndromes caused by mutations in Ca2+-handling proteins. Finally, we will discuss how changes in the expression of regulation of Ca2+ channels and transporters can cause acquired arrhythmias, and how these mechanisms might be targeted for therapeutic purposes.
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Affiliation(s)
- Andrew P Landstrom
- From the Section of Cardiology, Department of Pediatrics (A.P.L.), Cardiovascular Research Institute (A.P.L., X.H.T.W.), and Departments of Molecular Physiology and Biophysics, Medicine (Cardiology), Center for Space Medicine (X.H.T.W.), Baylor College of Medicine, Houston, TX; and Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (D.D.)
| | - Dobromir Dobrev
- From the Section of Cardiology, Department of Pediatrics (A.P.L.), Cardiovascular Research Institute (A.P.L., X.H.T.W.), and Departments of Molecular Physiology and Biophysics, Medicine (Cardiology), Center for Space Medicine (X.H.T.W.), Baylor College of Medicine, Houston, TX; and Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (D.D.)
| | - Xander H T Wehrens
- From the Section of Cardiology, Department of Pediatrics (A.P.L.), Cardiovascular Research Institute (A.P.L., X.H.T.W.), and Departments of Molecular Physiology and Biophysics, Medicine (Cardiology), Center for Space Medicine (X.H.T.W.), Baylor College of Medicine, Houston, TX; and Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Essen, Germany (D.D.).
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Dobrev D, Wehrens XHT. Calcium-mediated cellular triggered activity in atrial fibrillation. J Physiol 2017; 595:4001-4008. [PMID: 28181690 DOI: 10.1113/jp273048] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 01/25/2017] [Indexed: 12/29/2022] Open
Abstract
Although atrial fibrillation (AF) is the most commonly encountered cardiac arrhythmia, the basic mechanisms underlying this disorder remain incompletely understood. During the past decade or so, it has become clear that alterations in intracellular Ca2+ handling may play a role in the pathogenesis of AF. Studies in small and large animal models, as well as atrial samples from patients with different forms of AF, have implicated ryanodine receptor type 2 (RyR2) dysfunction and enhanced spontaneous Ca2+ release events from the sarcoplasmic reticulum (SR) as a potential cause of proarrhythmic cellular ectopic (triggered) activity in AF. The molecular mechanisms leading to RyR2 dysfunction and SR Ca2+ leak depend on the clinical stage of AF or specific animal model studied. This review focuses on the mechanisms and role of calcium-mediated cellular triggered activity in AF, and addresses some of the current controversies in the field.
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Affiliation(s)
- Dobromir Dobrev
- Institute for Pharmacology, West German Heart and Vascular Centre, University Duisburg-Essen, Essen, Germany.,Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA
| | - Xander H T Wehrens
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA.,Departments of Molecular Physiology & Biophysics, Pediatrics (Cardiology), Medicine (Cardiology), Baylor College of Medicine, Houston, TX, USA
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48
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Triggered activity in atrial myocytes is influenced by Na +/Ca 2+ exchanger activity in genetically altered mice. J Mol Cell Cardiol 2016; 101:106-115. [PMID: 27838371 DOI: 10.1016/j.yjmcc.2016.11.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Revised: 10/26/2016] [Accepted: 11/08/2016] [Indexed: 02/05/2023]
Abstract
AIMS In atrial fibrillation, increased function of the Na+/Ca2+-exchanger (NCX) is one among several electrical remodeling mechanisms. METHODS/RESULTS Using the patch-clamp- and Ca2+ imaging-methods, we investigated atrial myocytes from NCX-homozygous-overexpressor (OE)- and heterozygous-knockout (KO)-mice and their corresponding wildtypes (WTOE; WTKO). NCX mediated Ca2+ extrusion capacity was reduced in KO and increased in OE. There was no evidence for structural or molecular remodeling. During a proarrhythmic pacing-protocol, the number of low amplitude delayed afterdepolarizations (DADs) was unaltered in OE vs. WTOE and KO vs. WTKO. However, DADs triggered full spontaneous action potentials (sAP) significantly more often in OE vs. WTOE (ratio sAP/DAD: OE:0.18±0.05; WTOE:0.02±0.02; p<0.001). Using the same protocol, a DAD triggered an sAP by tendency less often in KO vs. WTKO (p=0.06) and significantly less often under a more aggressive proarrhythmic protocol (ratio sAP/DAD: KO:0.01±0.003; WT KO: 0.12±0.05; p=0.007). The DAD amplitude was increased in OE vs. WTOE and decreased in KO vs. WTKO. There were no differences in SR-Ca2+-load, the number of spontaneous Ca2+-release-events or IKACh/IK1. CONCLUSIONS Atrial myocytes with increased NCX expression exhibited increased vulnerability towards sAPs while atriomyocytes with reduced NCX expression were protected. The underlying mechanism consists of a modification of the DAD-amplitude by the level of NCX-activity. Thus, although the number of spontaneous Ca2+-releases and therefore DADs is unaltered, the higher DAD-amplitude in OE made a transgression of the voltage-threshold of an sAP more likely. These findings indicate that the level of NCX activity could influence triggered activity in atrial myocytes independent of possible remodeling processes.
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Abstract
Calcium/calmodulin-dependent protein kinase II (CaMKII) has emerged as key enzyme in many cardiac pathologies, especially heart failure (HF), myocardial infarction and cardiomyopathies, thus leading to contractile dysfunction and malignant arrhythmias. While many pathways leading to CaMKII activation have been elucidated in recent years, hardly any clinically viable compounds affecting CaMKII activity have progressed from basic in vitro science to in vivo studies. This review focuses on recent advances in anti-arrhythmic strategies involving CaMKII. Specifically, both inhibition of CaMKII itself to prevent arrhythmias, as well as anti-arrhythmic approaches affecting CaMKII activity via alterations in signaling cascades upstream and downstream of CaMKII will be discussed.
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Affiliation(s)
- Julian Mustroph
- Universitäres Herzzentrum Regensburg, Klinik und Poliklinik für Innere Medizin II, Universitätsklinikum Regensburg, Germany
| | - Stefan Neef
- Universitäres Herzzentrum Regensburg, Klinik und Poliklinik für Innere Medizin II, Universitätsklinikum Regensburg, Germany
| | - Lars S Maier
- Universitäres Herzzentrum Regensburg, Klinik und Poliklinik für Innere Medizin II, Universitätsklinikum Regensburg, Germany.
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50
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Hartmann N, Pabel S, Herting J, Schatter F, Renner A, Gummert J, Schotola H, Danner BC, Maier LS, Frey N, Hasenfuss G, Fischer TH, Sossalla S. Antiarrhythmic effects of dantrolene in human diseased cardiomyocytes. Heart Rhythm 2016; 14:412-419. [PMID: 27650424 DOI: 10.1016/j.hrthm.2016.09.014] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Indexed: 01/27/2023]
Abstract
BACKGROUND Cardiac type 2 ryanodine receptors (RyR2s) play a pivotal role in cellular electrophysiology and contractility. Increased RyR2-mediated diastolic sarcoplasmic reticulum (SR) Ca2+ release is linked to heart failure (HF) and arrhythmias. Dantrolene, a drug used for the treatment of malignant hyperthermia, is known to stabilize RyRs in skeletal muscle. OBJECTIVE The purpose of this study was to investigate the effects of dantrolene on arrhythmogenic triggers and contractile function in human atrial fibrillation (AF) and HF cardiomyocytes (CM). METHODS Human CM were isolated from either patients with HF (ventricular) or patients with AF (atrial), and Ca2+ imaging, patch-clamp, or muscle strip experiments were performed. RESULTS After exposure to dantrolene, human atrial AF and left ventricular HF CM showed significant reductions in proarrhythmic SR Ca2+ spark frequency and diastolic SR Ca2+ leak. Moreover, dantrolene decreased the frequency of Ca2+ waves and spontaneous Ca2+ transients in HF CM. Patch-clamp experiments revealed that dantrolene significantly suppressed delayed afterdepolarizations in HF and AF CM. Importantly, dantrolene had no effect on action potential duration in AF or in HF CM. In addition, dantrolene had neutral effects on contractile force of human isometrically twitching ventricular HF trabeculae. CONCLUSION Our study showed that dantrolene beneficially influenced disrupted SR Ca2+ homeostasis in human HF and AF CM. Cellular arrhythmogenic triggers were potently suppressed by dantrolene, whereas action potential duration and contractility were not affected. As a clinically approved drug for the treatment of malignant hyperthermia, dantrolene may be a potential antiarrhythmic drug for patients with rhythm disorders and merits further clinical investigation.
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Affiliation(s)
- Nico Hartmann
- Department of Cardiology and Pneumology, Georg-August-University Göttingen, Göttingen, Germany
| | - Steffen Pabel
- Department of Cardiology and Pneumology, Georg-August-University Göttingen, Göttingen, Germany
| | - Jonas Herting
- Department of Cardiology and Pneumology, Georg-August-University Göttingen, Göttingen, Germany
| | - Felix Schatter
- Department of Cardiology and Pneumology, Georg-August-University Göttingen, Göttingen, Germany
| | - André Renner
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Center NRW, Ruhr University Bochum, Bad Oeynhausen, Germany
| | - Jan Gummert
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Center NRW, Ruhr University Bochum, Bad Oeynhausen, Germany
| | - Hanna Schotola
- Department of Anesthesiology, Emergency and Intensive Care Medicine, Georg-August-University Göttingen, Göttingen, Germany
| | - Bernhard C Danner
- Department of Thoracic and Cardiovascular Surgery, Georg-August-University Göttingen, Göttingen, Germany
| | - Lars S Maier
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Norbert Frey
- Department of Internal Medicine III: Cardiology and Angiology, University of Kiel, Kiel, Germany; DZHK (German Center for Cardiovascular Research), partner site Göttingen, Göttingen, Germany
| | - Gerd Hasenfuss
- Department of Cardiology and Pneumology, Georg-August-University Göttingen, Göttingen, Germany; DZHK (German Center for Cardiovascular Research), partner site Göttingen, Göttingen, Germany
| | - Thomas H Fischer
- Department of Cardiology and Pneumology, Georg-August-University Göttingen, Göttingen, Germany
| | - Samuel Sossalla
- Department of Cardiology and Pneumology, Georg-August-University Göttingen, Göttingen, Germany; Department of Internal Medicine III: Cardiology and Angiology, University of Kiel, Kiel, Germany; DZHK (German Center for Cardiovascular Research), partner site Göttingen, Göttingen, Germany.
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