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Baines O, Sha R, Kalla M, Holmes AP, Efimov IR, Pavlovic D, O’Shea C. Optical mapping and optogenetics in cardiac electrophysiology research and therapy: a state-of-the-art review. Europace 2024; 26:euae017. [PMID: 38227822 PMCID: PMC10847904 DOI: 10.1093/europace/euae017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 12/07/2023] [Accepted: 01/12/2024] [Indexed: 01/18/2024] Open
Abstract
State-of-the-art innovations in optical cardiac electrophysiology are significantly enhancing cardiac research. A potential leap into patient care is now on the horizon. Optical mapping, using fluorescent probes and high-speed cameras, offers detailed insights into cardiac activity and arrhythmias by analysing electrical signals, calcium dynamics, and metabolism. Optogenetics utilizes light-sensitive ion channels and pumps to realize contactless, cell-selective cardiac actuation for modelling arrhythmia, restoring sinus rhythm, and probing complex cell-cell interactions. The merging of optogenetics and optical mapping techniques for 'all-optical' electrophysiology marks a significant step forward. This combination allows for the contactless actuation and sensing of cardiac electrophysiology, offering unprecedented spatial-temporal resolution and control. Recent studies have performed all-optical imaging ex vivo and achieved reliable optogenetic pacing in vivo, narrowing the gap for clinical use. Progress in optical electrophysiology continues at pace. Advances in motion tracking methods are removing the necessity of motion uncoupling, a key limitation of optical mapping. Innovations in optoelectronics, including miniaturized, biocompatible illumination and circuitry, are enabling the creation of implantable cardiac pacemakers and defibrillators with optoelectrical closed-loop systems. Computational modelling and machine learning are emerging as pivotal tools in enhancing optical techniques, offering new avenues for analysing complex data and optimizing therapeutic strategies. However, key challenges remain including opsin delivery, real-time data processing, longevity, and chronic effects of optoelectronic devices. This review provides a comprehensive overview of recent advances in optical mapping and optogenetics and outlines the promising future of optics in reshaping cardiac electrophysiology and therapeutic strategies.
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Affiliation(s)
- Olivia Baines
- Institute of Cardiovascular Sciences, College of Medical and Dental Science, University of Birmingham, Edgbastion, Wolfson Drive, Birmingham B15 2TT, UK
| | - Rina Sha
- Institute of Cardiovascular Sciences, College of Medical and Dental Science, University of Birmingham, Edgbastion, Wolfson Drive, Birmingham B15 2TT, UK
| | - Manish Kalla
- Institute of Cardiovascular Sciences, College of Medical and Dental Science, University of Birmingham, Edgbastion, Wolfson Drive, Birmingham B15 2TT, UK
| | - Andrew P Holmes
- Institute of Cardiovascular Sciences, College of Medical and Dental Science, University of Birmingham, Edgbastion, Wolfson Drive, Birmingham B15 2TT, UK
| | - Igor R Efimov
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, USA
- Department of Medicine, Division of Cardiology, Northwestern University, Evanston, IL, USA
| | - Davor Pavlovic
- Institute of Cardiovascular Sciences, College of Medical and Dental Science, University of Birmingham, Edgbastion, Wolfson Drive, Birmingham B15 2TT, UK
| | - Christopher O’Shea
- Institute of Cardiovascular Sciences, College of Medical and Dental Science, University of Birmingham, Edgbastion, Wolfson Drive, Birmingham B15 2TT, UK
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2
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You T, Xie Y, Luo C, Zhang K, Zhang H. Mechanistic insights into spontaneous transition from cellular alternans to ventricular fibrillation. Physiol Rep 2023; 11:e15619. [PMID: 36863774 PMCID: PMC9981424 DOI: 10.14814/phy2.15619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Revised: 02/04/2023] [Accepted: 02/05/2023] [Indexed: 03/04/2023] Open
Abstract
T-wave alternans (TWA) has been used for predicting the risk of malignant cardiac arrhythmias and sudden cardiac death (SCD) in multiple clinical settings; however, possible mechanism(s) underlying the spontaneous transition from cellular alternans reflected by TWA to arrhythmias in impaired repolarization remains unclear. The healthy guinea pig ventricular myocytes under E-4031 blocking IKr (0.1 μM, N = 12; 0.3 μM, N = 10; 1 μM, N = 10) were evaluated using whole-cell patch-clamp. The electrophysiological properties of isolated perfused guinea pig hearts under E-4031 (0.1 μM, N = 5; 0.3 μM, N = 5; 1 μM, N = 5) were evaluated using dual- optical mapping. The amplitude/threshold/restitution curves of action potential duration (APD) alternans and potential mechanism(s) underlying the spontaneous transition of cellular alternans to ventricular fibrillation (VF) were examined. There were longer APD80 and increased amplitude and threshold of APD alternans in E-4031 group compared with baseline group, which was reflected by more pronounced arrhythmogenesis at the tissue level, and were associated with steep restitution curves of the APD and the conduction velocity (CV). Conduction of AP alternans augmented tissue's functional spatiotemporal heterogeneity of regional AP/Ca alternans, as well as the AP/Ca dispersion, leading to localized uni-directional conduction block that spontaneous facilitated the formation of reentrant excitation waves without the need for additional premature stimulus. Our results provide a possible mechanism for the spontaneous transition from cardiac electrical alternans in cellular action potentials and intercellular conduction without the involvement of premature excitations, and explain the increased susceptibility to ventricular arrhythmias in impaired repolarization. In this study, we implemented voltage-clamp and dual-optical mapping approaches to investigate the underlying mechanism(s) for the arrhythmogenesis of cardiac alternans in the guinea pig heart at cellular and tissue levels. Our results demonstrated a spontaneous development of reentry from cellular alternans, arising from a combined actions of restitution properties of action potential duration, conduction velocity of excitation wave and interplay between alternants of action potential and the intracellular Ca handling. We believe this study provides new insights into underlying the mechanism, by which cellular cardiac alternans spontaneously evolves into cardiac arrhythmias.
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Affiliation(s)
- Tingting You
- Key Laboratory of Medical Electrophysiology, Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, (Collaborative Innovation Center for Prevention of Cardiovascular Diseases)Institute of Cardiovascular Research, Southwest Medical UniversityLuzhouChina
- Department of NeurosurgeryXinqiao Hospital, Army Medical UniversityChongqingChina
| | - Yulong Xie
- Key Laboratory of Medical Electrophysiology, Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, (Collaborative Innovation Center for Prevention of Cardiovascular Diseases)Institute of Cardiovascular Research, Southwest Medical UniversityLuzhouChina
| | - Cunjin Luo
- School of Computer Science and Electronic EngineeringUniversity of EssexColchesterUK
| | - Kevin Zhang
- School of MedicineImperial College of LondonLondonUK
| | - Henggui Zhang
- Key Laboratory of Medical Electrophysiology, Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, (Collaborative Innovation Center for Prevention of Cardiovascular Diseases)Institute of Cardiovascular Research, Southwest Medical UniversityLuzhouChina
- Department of Physics and AstronomyUniversity of ManchesterManchesterUK
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O'Shea C, Winter J, Kabir SN, O'Reilly M, Wells SP, Baines O, Sommerfeld LC, Correia J, Lei M, Kirchhof P, Holmes AP, Fabritz L, Rajpoot K, Pavlovic D. High resolution optical mapping of cardiac electrophysiology in pre-clinical models. Sci Data 2022; 9:135. [PMID: 35361792 PMCID: PMC8971487 DOI: 10.1038/s41597-022-01253-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 03/07/2022] [Indexed: 11/08/2022] Open
Abstract
Optical mapping of animal models is a widely used technique in pre-clinical cardiac research. It has several advantages over other methods, including higher spatial resolution, contactless recording and direct visualisation of action potentials and calcium transients. Optical mapping enables simultaneous study of action potential and calcium transient morphology, conduction dynamics, regional heterogeneity, restitution and arrhythmogenesis. In this dataset, we have optically mapped Langendorff perfused isolated whole hearts (mouse and guinea pig) and superfused isolated atria (mouse). Raw datasets (consisting of over 400 files) can be combined with open-source software for processing and analysis. We have generated a comprehensive post-processed dataset characterising the baseline cardiac electrophysiology in these widely used pre-clinical models. This dataset also provides reference information detailing the effect of heart rate, clinically used anti-arrhythmic drugs, ischaemia-reperfusion and sympathetic nervous stimulation on cardiac electrophysiology. The effects of these interventions can be studied in a global or regional manner, enabling new insights into the prevention and initiation of arrhythmia.
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Affiliation(s)
- Christopher O'Shea
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK.
| | - James Winter
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
| | - S Nashitha Kabir
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
| | - Molly O'Reilly
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
- Heart Center, Department of Clinical and Experimental Cardiology, Amsterdam UMC, location AMC, Amsterdam, The Netherlands
| | - Simon P Wells
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
- William Harvey Research Institute, Queen Mary University of London, London, UK
| | - Olivia Baines
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
| | - Laura C Sommerfeld
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
- University Center of Cardiovascular Science, UKE, Hamburg, Germany
| | - Joao Correia
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
| | - Ming Lei
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Paulus Kirchhof
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
- Department of Cardiology, University Heart and Vascular Centre, University Medical Center Hamburg-Eppendorf, Germany and German Center for Cardiovascular Research (DZHK) partner site Hamburg/Kiel/Lubeck, Lubeck, Germany
- University Center of Cardiovascular Science, UKE, Hamburg, Germany
| | - Andrew P Holmes
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
- Institute of Clinical Sciences, University of Birmingham, Birmingham, UK
| | - Larissa Fabritz
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
- Department of Cardiology, University Heart and Vascular Centre, University Medical Center Hamburg-Eppendorf, Germany and German Center for Cardiovascular Research (DZHK) partner site Hamburg/Kiel/Lubeck, Lubeck, Germany
- University Center of Cardiovascular Science, UKE, Hamburg, Germany
| | - Kashif Rajpoot
- School of Computer Science, University of Birmingham, Birmingham, UK
| | - Davor Pavlovic
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
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4
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Cumberland MJ, Riebel LL, Roy A, O’Shea C, Holmes AP, Denning C, Kirchhof P, Rodriguez B, Gehmlich K. Basic Research Approaches to Evaluate Cardiac Arrhythmia in Heart Failure and Beyond. Front Physiol 2022; 13:806366. [PMID: 35197863 PMCID: PMC8859441 DOI: 10.3389/fphys.2022.806366] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 01/10/2022] [Indexed: 12/20/2022] Open
Abstract
Patients with heart failure often develop cardiac arrhythmias. The mechanisms and interrelations linking heart failure and arrhythmias are not fully understood. Historically, research into arrhythmias has been performed on affected individuals or in vivo (animal) models. The latter however is constrained by interspecies variation, demands to reduce animal experiments and cost. Recent developments in in vitro induced pluripotent stem cell technology and in silico modelling have expanded the number of models available for the evaluation of heart failure and arrhythmia. An agnostic approach, combining the modalities discussed here, has the potential to improve our understanding for appraising the pathology and interactions between heart failure and arrhythmia and can provide robust and validated outcomes in a variety of research settings. This review discusses the state of the art models, methodologies and techniques used in the evaluation of heart failure and arrhythmia and will highlight the benefits of using them in combination. Special consideration is paid to assessing the pivotal role calcium handling has in the development of heart failure and arrhythmia.
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Affiliation(s)
- Max J. Cumberland
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Leto L. Riebel
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Ashwin Roy
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Christopher O’Shea
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Andrew P. Holmes
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
- Institute of Clinical Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Chris Denning
- Stem Cell Biology Unit, Biodiscovery Institute, British Heart Foundation Centre for Regenerative Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Paulus Kirchhof
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
- University Heart and Vascular Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Blanca Rodriguez
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Katja Gehmlich
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
- Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford and British Heart Foundation Centre of Research Excellence Oxford, Oxford, United Kingdom
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5
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Optogenetic manipulation of cardiac electrical dynamics using sub-threshold illumination: dissecting the role of cardiac alternans in terminating rapid rhythms. Basic Res Cardiol 2022; 117:25. [PMID: 35488105 PMCID: PMC9054908 DOI: 10.1007/s00395-022-00933-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 04/01/2022] [Accepted: 04/18/2022] [Indexed: 02/01/2023]
Abstract
Cardiac action potential (AP) shape and propagation are regulated by several key dynamic factors such as ion channel recovery and intracellular Ca2+ cycling. Experimental methods for manipulating AP electrical dynamics commonly use ion channel inhibitors that lack spatial and temporal specificity. In this work, we propose an approach based on optogenetics to manipulate cardiac electrical activity employing a light-modulated depolarizing current with intensities that are too low to elicit APs (sub-threshold illumination), but are sufficient to fine-tune AP electrical dynamics. We investigated the effects of sub-threshold illumination in isolated cardiomyocytes and whole hearts by using transgenic mice constitutively expressing a light-gated ion channel (channelrhodopsin-2, ChR2). We find that ChR2-mediated depolarizing current prolongs APs and reduces conduction velocity (CV) in a space-selective and reversible manner. Sub-threshold manipulation also affects the dynamics of cardiac electrical activity, increasing the magnitude of cardiac alternans. We used an optical system that uses real-time feedback control to generate re-entrant circuits with user-defined cycle lengths to explore the role of cardiac alternans in spontaneous termination of ventricular tachycardias (VTs). We demonstrate that VT stability significantly decreases during sub-threshold illumination primarily due to an increase in the amplitude of electrical oscillations, which implies that cardiac alternans may be beneficial in the context of self-termination of VT.
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He S, Kou K, O'Shea C, Chen T, Mu-U-Min R, Dong R, Ren H, Zhou X, Fan Z, Tan X, Pavlovic D, Ou X, Lei M. A dataset of dual calcium and voltage optical mapping in healthy and hypertrophied murine hearts. Sci Data 2021; 8:314. [PMID: 34916511 PMCID: PMC8677726 DOI: 10.1038/s41597-021-01085-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 11/01/2021] [Indexed: 11/18/2022] Open
Abstract
Pathological hypertrophy underlies sudden cardiac death due to its high incidence of occurrence of ventricular arrhythmias. The alteration of transmural electrophysiological properties in hypertrophic cardiac murine tissue has never been explored previously. In this dataset, we have for the first time conducted high-throughput simultaneous optical imaging of transmembrane potential and calcium transients (CaT) throughout the entire hypertrophic murine hearts at high temporal and spatial resolution. Using ElectroMap, we have conducted multiple parameters analysis including action potential duration/calcium transient duration, conduction velocity, alternans and diastolic interval. Voltage-calcium latency was measured as time difference between action potential and CaT peak. The dataset therefore provides the first high spatial resolution transmural electrophysiological profiling of the murine heart, allowing interrogation of mechanisms driving ventricular arrhythmias associated with pathological hypertrophy. The dataset allows for further reuse and detailed analyses of geometrical, topological and functional analyses and reconstruction of 2-dimensional and 3-dimentional models.
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Affiliation(s)
- Shicheng He
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
- Department of Cardiovascular Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Kun Kou
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
- Department of Cardiovascular Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Christopher O'Shea
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Tangting Chen
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Razik Mu-U-Min
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Ruirui Dong
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Huiying Ren
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
- Department of Cardiovascular Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Xiaolin Zhou
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Zhongcai Fan
- Department of Cardiovascular Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Xiaoqiu Tan
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
- Department of Cardiovascular Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Davor Pavlovic
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Xianhong Ou
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China.
- Department of Cardiovascular Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China.
| | - Ming Lei
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China.
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom.
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7
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Sadredini M, Haugsten Hansen M, Frisk M, Louch WE, Lehnart SE, Sjaastad I, Stokke MK. CaMKII inhibition has dual effects on spontaneous Ca 2+ release and Ca 2+ alternans in ventricular cardiomyocytes from mice with a gain-of-function RyR2 mutation. Am J Physiol Heart Circ Physiol 2021; 321:H446-H460. [PMID: 34270372 DOI: 10.1152/ajpheart.00011.2021] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In conditions with abnormally increased activity of the cardiac ryanodine receptor (RyR2), Ca2+/calmodulin-dependent protein kinase II (CaMKII) can contribute to a further destabilization of RyR2 that results in triggered arrhythmias. Therefore, inhibition of CaMKII in such conditions has been suggested as a strategy to suppress RyR2 activity and arrhythmias. However, suppression of RyR2 activity can lead to the development of arrhythmogenic Ca2+ alternans. The aim of this study was to test whether the suppression of RyR2 activity caused by inhibition of CaMKII increases propensity for Ca2+ alternans. We studied spontaneous Ca2+ release events and Ca2+ alternans in isolated left ventricular cardiomyocytes from mice carrying the gain-of-function RyR2 mutation RyR2-R2474S and from wild-type mice. CaMKII inhibition by KN-93 effectively decreased the frequency of spontaneous Ca2+ release events in RyR2-R2474S cardiomyocytes exposed to the β-adrenoceptor agonist isoprenaline. However, KN-93-treated RyR2-R2474S cardiomyocytes also showed increased propensity for Ca2+ alternans and increased Ca2+ alternans ratio compared with both an inactive analog of KN-93 and with vehicle-treated controls. This increased propensity for Ca2+ alternans was explained by prolongation of Ca2+ release refractoriness. Importantly, the increased propensity for Ca2+ alternans in KN-93-treated RyR2-R2474S cardiomyocytes did not surpass that of wild type. In conclusion, inhibition of CaMKII efficiently reduces spontaneous Ca2+ release but promotes Ca2+ alternans in RyR2-R2474S cardiomyocytes with a gain-of-function RyR2 mutation. The dominant effect in RyR2-R2474S is to reduce spontaneous Ca2+ release, which supports this intervention as a therapeutic strategy in this specific condition. However, future studies on CaMKII inhibition in conditions with increased propensity for Ca2+ alternans should include investigation of both phenomena.NEW & NOTEWORTHY Genetically increased RyR2 activity promotes arrhythmogenic Ca2+ release. Inhibition of CaMKII suppresses RyR2 activity and arrhythmogenic Ca2+ release. Suppression of RyR2 activity prolongs refractoriness of Ca2+ release. Prolonged refractoriness of Ca2+ release leads to arrhythmogenic Ca2+ alternans. CaMKII inhibition promotes Ca2+ alternans by prolonging Ca2+ release refractoriness.
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Affiliation(s)
- Mani Sadredini
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway.,KG Jebsen Cardiac Research Centre, University of Oslo, Oslo, Norway
| | - Marie Haugsten Hansen
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway.,KG Jebsen Cardiac Research Centre, University of Oslo, Oslo, Norway
| | - Michael Frisk
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway.,KG Jebsen Cardiac Research Centre, University of Oslo, Oslo, Norway
| | - William E Louch
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway.,KG Jebsen Cardiac Research Centre, University of Oslo, Oslo, Norway
| | - Stephan E Lehnart
- Department of Cardiology and Pulmonology, Heart Research Center Göttingen, University Medical Center Göttingen, Göttingen, Germany.,Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, Göttingen, Germany.,DZHK (German Centre for Cardiovascular Research), Göttingen, Germany
| | - Ivar Sjaastad
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway.,KG Jebsen Cardiac Research Centre, University of Oslo, Oslo, Norway
| | - Mathis Korseberg Stokke
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway.,KG Jebsen Cardiac Research Centre, University of Oslo, Oslo, Norway.,Department of Cardiology, Oslo University Hospital, Rikshospitalet, Oslo, Norway
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8
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Arslanova A, Shafaattalab S, Lin E, Barszczewski T, Hove-Madsen L, Tibbits GF. Investigating inherited arrhythmias using hiPSC-derived cardiomyocytes. Methods 2021; 203:542-557. [PMID: 34197925 DOI: 10.1016/j.ymeth.2021.06.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 06/22/2021] [Accepted: 06/23/2021] [Indexed: 10/21/2022] Open
Abstract
Fundamental to the functional behavior of cardiac muscle is that the cardiomyocytes are integrated as a functional syncytium. Disrupted electrical activity in the cardiac tissue can lead to serious complications including cardiac arrhythmias. Therefore, it is important to study electrophysiological properties of the cardiac tissue. With advancements in stem cell research, protocols for the production of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have been established, providing great potential in modelling cardiac arrhythmias and drug testing. The hiPSC-CM model can be used in conjunction with electrophysiology-based platforms to examine the electrical activity of the cardiac tissue. Techniques for determining the myocardial electrical activity include multielectrode arrays (MEAs), optical mapping (OM), and patch clamping. These techniques provide critical approaches to investigate cardiac electrical abnormalities that underlie arrhythmias.
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Affiliation(s)
- Alia Arslanova
- Molecular Cardiac Physiology Group, Department of Biomedical Physiology and Kinesiology, Simon Fraser, University, Burnaby, BC V5A 1S6, Canada; hiPSC-CM Research Team, British Columbia Children's Hospital Research Institute, Vancouver, BC V5Z4H4, Canada
| | - Sanam Shafaattalab
- Molecular Cardiac Physiology Group, Department of Biomedical Physiology and Kinesiology, Simon Fraser, University, Burnaby, BC V5A 1S6, Canada; hiPSC-CM Research Team, British Columbia Children's Hospital Research Institute, Vancouver, BC V5Z4H4, Canada
| | - Eric Lin
- Molecular Cardiac Physiology Group, Department of Biomedical Physiology and Kinesiology, Simon Fraser, University, Burnaby, BC V5A 1S6, Canada
| | - Tiffany Barszczewski
- Molecular Cardiac Physiology Group, Department of Biomedical Physiology and Kinesiology, Simon Fraser, University, Burnaby, BC V5A 1S6, Canada; hiPSC-CM Research Team, British Columbia Children's Hospital Research Institute, Vancouver, BC V5Z4H4, Canada
| | - Leif Hove-Madsen
- Cardiac Rhythm and Contraction Group, IIBB-CSIC, Hospital de la Santa Creu i Sant Pau, Barcelona 08041, Spain; CIBERCV, Hospital de la Santa Creu i Sant Pau, Barcelona 08041, Spain; IIB Sant Pau, Hospital de la Santa Creu i Sant Pau, Barcelona 08041, Spain
| | - Glen F Tibbits
- Molecular Cardiac Physiology Group, Department of Biomedical Physiology and Kinesiology, Simon Fraser, University, Burnaby, BC V5A 1S6, Canada; hiPSC-CM Research Team, British Columbia Children's Hospital Research Institute, Vancouver, BC V5Z4H4, Canada; Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada.
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9
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You T, Luo C, Zhang K, Zhang H. Electrophysiological Mechanisms Underlying T-Wave Alternans and Their Role in Arrhythmogenesis. Front Physiol 2021; 12:614946. [PMID: 33746768 PMCID: PMC7969788 DOI: 10.3389/fphys.2021.614946] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 02/10/2021] [Indexed: 12/18/2022] Open
Abstract
T-wave alternans (TWA) reflects every-other-beat alterations in the morphology of the electrocardiogram ST segment or T wave in the setting of a constant heart rate, hence, in the absence of heart rate variability. It is believed to be associated with the dispersion of repolarization and has been used as a non-invasive marker for predicting the risk of malignant cardiac arrhythmias and sudden cardiac death as numerous studies have shown. This review aims to provide up-to-date review on both experimental and simulation studies in elucidating possible mechanisms underlying the genesis of TWA at the cellular level, as well as the genesis of spatially concordant/discordant alternans at the tissue level, and their transition to cardiac arrhythmia. Recent progress and future perspectives in antiarrhythmic therapies associated with TWA are also discussed.
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Affiliation(s)
- Tingting You
- Key Lab of Medical Electrophysiology, Ministry of Education, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Cunjin Luo
- School of Computer Science and Electronic Engineering, University of Essex, Colchester, United Kingdom
| | - Kevin Zhang
- School of Medicine, Imperial College of London, London, United Kingdom
| | - Henggui Zhang
- Key Lab of Medical Electrophysiology, Ministry of Education, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China.,Department of Physics and Astronomy, University of Manchester, Manchester, United Kingdom
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10
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Martišienė I, Mačianskienė R, Benetis R, Jurevičius J. Cardiac Optical Mapping in Situ in Swine Models: A View of the Current Situation. MEDICINA-LITHUANIA 2020; 56:medicina56110620. [PMID: 33217906 PMCID: PMC7698624 DOI: 10.3390/medicina56110620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 11/10/2020] [Accepted: 11/16/2020] [Indexed: 11/16/2022]
Abstract
Optical mapping is recognized as a promising tool for the registration of electrical activity in the heart. Most cardiac optical mapping experiments are performed in ex vivo isolated heart models. However, the electrophysiological properties of the heart are highly influenced by the autonomic nervous system as well as humoral regulation; therefore, in vivo investigations of heart activity in large animals are definitely preferred. Furthermore, such investigations can be considered the last step before clinical application. Recently, two comprehensive studies have examined optical mapping approaches for pig hearts in situ (in vivo), likely advancing the methodological capacity to perform complex electrophysiological investigations of the heart. Both studies had the same aim, i.e., to develop high-spatiotemporal-resolution optical mapping suitable for registration of electrical activity of pig heart in situ, but the methods chosen were different. In this brief review, we analyse and compare the results of recent studies and discuss their translational potential for in situ cardiac optical mapping applications in large animals. We focus on the modes of blood circulation that are employed, the use of different voltage-sensitive dyes and their loading procedures, and ways of eliminating contraction artefacts. Finally, we evaluate the possible scenarios for optical mapping (OM) application in large animals in situ and infer which scenario is optimal.
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Affiliation(s)
- Irma Martišienė
- Institute of Cardiology, Lithuanian University of Health Sciences, LT-50161 Kaunas, Lithuania; (I.M.); (R.M.); (R.B.)
| | - Regina Mačianskienė
- Institute of Cardiology, Lithuanian University of Health Sciences, LT-50161 Kaunas, Lithuania; (I.M.); (R.M.); (R.B.)
| | - Rimantas Benetis
- Institute of Cardiology, Lithuanian University of Health Sciences, LT-50161 Kaunas, Lithuania; (I.M.); (R.M.); (R.B.)
- Department of Cardiac, Thoracic and Vascular Surgery, Hospital of Lithuanian University of Health Sciences Kauno Klinikos, Lithuanian University of Health Sciences, LT-50161 Kaunas, Lithuania
| | - Jonas Jurevičius
- Institute of Cardiology, Lithuanian University of Health Sciences, LT-50161 Kaunas, Lithuania; (I.M.); (R.M.); (R.B.)
- Correspondence:
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11
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Zhang W, Zhu B, Ding S, Wang X, Wu J, Zhu X, Zou Y, Ge J, Tong M, Yang X. Disruption of STAT6 Signal Promotes Cardiac Fibrosis Through the Mobilization and Transformation of CD11b + Immature Myeloid Cells. Front Physiol 2020; 11:579712. [PMID: 33192584 PMCID: PMC7642801 DOI: 10.3389/fphys.2020.579712] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 09/16/2020] [Indexed: 12/23/2022] Open
Abstract
Cardiac fibrosis is an important pathological basis of various cardiovascular diseases. The roles of STAT6 signal in allergy, immune regulation, tumorigenesis, and renal fibrosis have been documented. However, the function and mechanism of STAT6 signal in sympathetic overactivation-induced cardiac fibrosis have not been fully elucidated. This study explores the novel role of STAT6 signal in isoproterenol (ISO)-induced cardiac fibrosis through the regulation of inflammatory response and the differentiation of macrophages from immature myeloid cells. The expression levels of STAT6, β1-adrenergic receptor (β1-AR), and inflammatory factors [interleukin α (IL-1α), IL-6, IL-18, and transforming growth factor β (TGF-β)] in CD11b+ myeloid cells were analyzed with a microarray study. The levels of IL-6 and TGF-β1 in the CD11b+ myeloid cells-derived macrophages were detected with reverse transcriptase-polymerase chain reaction (RT-PCR). STAT6-knockout (KO) and WT mice were used to establish a murine cardiac fibrosis model by ISO injection. Cardiac fibroblasts were isolated from the hearts of newborn STAT6-KO and WT mice, and STAT6 expression was measured by Western blotting and RT-PCR after ISO stimulation, while α-smooth muscle actin (α-SMA) expression was detected by immunofluorescence and immunohistochemistry staining. Cardiac function and pathological characteristics were examined by echocardiography and immunohistochemistry staining, respectively. Immunohistochemistry staining with anti-CD11b was performed to detect the infiltration of CD11b+ myeloid cells in heart tissue. Flow cytometry analysis was used to measure the percentages of CD11b+ myeloid cells and CD11b+Ly6C+ macrophages in the peripheral blood. The results showed that STAT6 was highly expressed in CD11b+ myeloid cells located in injured hearts, and STAT6 expression in cardiac fibroblasts was down-regulated after ISO treatment. STAT6 deficiency further aggravated ISO-induced increased expression of α-SMA in cardiac fibroblasts, myocardial fibrosis, and cardiac dysfunction. The activation of ISO/β1-AR signal aggravated cardiac inflammatory infiltration, promoted CD11b+ myeloid cell mobilization, and enhanced CD11b+Ly6C+/low macrophage differentiation, which was further exacerbated by STAT6 deficiency. Furthermore, β1-AR mRNA expression significantly increased in splenic CD11b+ myeloid cells compared to their bone marrow-derived controls, and STAT6 deficiency promoted β1-AR expression in an MI-induced sensitive cardiac fibrosis mouse model. The spleen-derived CD11b+ myeloid cells of STAT6-KO mice produced more IL-1α, IL-18, and TGF-β than their WT counterparts. Taken together, these results suggest that STAT6 signal plays a critical role in ISO-induced β1-AR overactivation and systemic inflammatory cascades, contributing to cardiac fibrogenesis. STAT6 should be a promising cardioprotective target against myocardial fibrosis and heart failure after β1-AR overactivation-induced myocardial injury.
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Affiliation(s)
- Weiwei Zhang
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Baoling Zhu
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China.,Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Suling Ding
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Xiangfei Wang
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China.,Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Jian Wu
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China.,Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Xiaowei Zhu
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China.,Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yunzeng Zou
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China.,Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Junbo Ge
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China.,Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Minghong Tong
- Division of Clinical Laboratory, TongRen Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiangdong Yang
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China.,Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, China
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O'Shea C, Winter J, Holmes AP, Johnson DM, Correia JN, Kirchhof P, Fabritz L, Rajpoot K, Pavlovic D. Temporal irregularity quantification and mapping of optical action potentials using wave morphology similarity. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2020; 157:84-93. [PMID: 31899215 PMCID: PMC7607254 DOI: 10.1016/j.pbiomolbio.2019.12.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 11/08/2019] [Accepted: 12/20/2019] [Indexed: 01/14/2023]
Abstract
BACKGROUND Cardiac optical mapping enables direct and high spatio-temporal resolution recording of action potential (AP) morphology. Temporal alterations in AP morphology are both predictive and consequent of arrhythmia. Here we sought to test if methods that quantify regularity of recorded waveforms could be applied to detect and quantify periods of temporal instability in optical mapping datasets in a semi-automated, user-unbiased manner. METHODS AND RESULTS We developed, tested and applied algorithms to quantify optical wave similarity (OWS) to study morphological temporal similarity of optically recorded APs. Unlike other measures (e.g. alternans ratio, beat-to-beat variability, arrhythmia scoring), the quantification of OWS is achieved without a restrictive definition of specific signal points/features and is instead derived by analysing the complete morphology from the entire AP waveform. Using model datasets, we validated the ability of OWS to measure changes in AP morphology, and tested OWS mapping in guinea pig hearts and mouse atria. OWS successfully detected and measured alterations in temporal regularity in response to several proarrhythmic stimuli, including alterations in pacing frequency, premature contractions, alternans and ventricular fibrillation. CONCLUSION OWS mapping provides an effective measure of temporal regularity that can be applied to optical datasets to detect and quantify temporal alterations in action potential morphology. This methodology provides a new metric for arrhythmia inducibility and scoring in optical mapping datasets.
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Affiliation(s)
- Christopher O'Shea
- Institute of Cardiovascular Sciences, University of Birmingham, UK; EPSRC Centre for Doctoral Training in Physical Sciences for Health, School of Chemistry, University of Birmingham, UK; School of Computer Science, University of Birmingham, Birmingham, B15 2TT, UK
| | - James Winter
- Institute of Cardiovascular Sciences, University of Birmingham, UK
| | - Andrew P Holmes
- Institute of Cardiovascular Sciences, University of Birmingham, UK; Institute of Clinical Sciences, University of Birmingham, UK
| | - Daniel M Johnson
- Institute of Cardiovascular Sciences, University of Birmingham, UK
| | - Joao N Correia
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, UK
| | - Paulus Kirchhof
- Institute of Cardiovascular Sciences, University of Birmingham, UK; Department of Cardiology, UHB NHS Foundation Trust, Birmingham, UK; Cardiology Specialty, SWBH NHS Trust, Birmingham, UK
| | - Larissa Fabritz
- Institute of Cardiovascular Sciences, University of Birmingham, UK; Department of Cardiology, UHB NHS Foundation Trust, Birmingham, UK
| | - Kashif Rajpoot
- School of Computer Science, University of Birmingham, Birmingham, B15 2TT, UK.
| | - Davor Pavlovic
- Institute of Cardiovascular Sciences, University of Birmingham, UK.
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13
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Optical mapping of the pig heart in situ under artificial blood circulation. Sci Rep 2020; 10:8548. [PMID: 32444634 PMCID: PMC7244500 DOI: 10.1038/s41598-020-65464-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 04/22/2020] [Indexed: 12/05/2022] Open
Abstract
The emergence of optical imaging has revolutionized the investigation of cardiac electrical activity and associated disorders in various cardiac pathologies. The electrical signals of the heart and the propagation pathways are crucial for elucidating the mechanisms of various cardiac pathological conditions, including arrhythmia. The synthesis of near-infrared voltage-sensitive dyes and the voltage sensitivity of the FDA-approved dye Cardiogreen have increased the importance of optical mapping (OM) as a prospective tool in clinical practice. We aimed to develop a method for the high-spatiotemporal-resolution OM of the large animal hearts in situ using di-4-ANBDQBS and Cardiogreen under patho/physiological conditions. OM was adapted to monitor cardiac electrical behaviour in an open-chest pig heart model with physiological or artificial blood circulation. We detail the methods and display the OM data obtained using di-4-ANBDQBS and Cardiogreen. Activation time, action potential duration, repolarization time and conduction velocity maps were constructed. The technique was applied to track cardiac electrical activity during regional ischaemia and arrhythmia. Our study is the first to apply high-spatiotemporal-resolution OM in the pig heart in situ to record cardiac electrical activity qualitatively under artificial blood perfusion. The use of an FDA-approved voltage-sensitive dye and artificial blood perfusion in a swine model, which is generally accepted as a valuable pre-clinical model, demonstrates the promise of OM for clinical application.
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14
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Abstract
The aim of this chapter is to discuss evidence concerning the many roles of calcium ions, Ca2+, in cell signaling pathways that control heart function. Before considering details of these signaling pathways, the control of contraction in ventricular muscle by Ca2+ transients accompanying cardiac action potentials is first summarized, together with a discussion of how myocytes from the atrial and pacemaker regions of the heart diverge from this basic scheme. Cell signaling pathways regulate the size and timing of the Ca2+ transients in the different heart regions to influence function. The simplest Ca2+ signaling elements involve enzymes that are regulated by cytosolic Ca2+. Particularly important examples to be discussed are those that are stimulated by Ca2+, including Ca2+-calmodulin-dependent kinase (CaMKII), Ca2+ stimulated adenylyl cyclases, Ca2+ stimulated phosphatase and NO synthases. Another major aspect of Ca2+ signaling in the heart concerns actions of the Ca2+ mobilizing agents, inositol trisphosphate (IP3), cADP-ribose (cADPR) and nicotinic acid adenine dinucleotide phosphate, (NAADP). Evidence concerning roles of these Ca2+ mobilizing agents in different regions of the heart is discussed in detail. The focus of the review will be on short term regulation of Ca2+ transients and contractile function, although it is recognized that Ca2+ regulation of gene expression has important long term functional consequences which will also be briefly discussed.
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O’Shea C, Holmes AP, Winter J, Correia J, Ou X, Dong R, He S, Kirchhof P, Fabritz L, Rajpoot K, Pavlovic D. Cardiac Optogenetics and Optical Mapping - Overcoming Spectral Congestion in All-Optical Cardiac Electrophysiology. Front Physiol 2019; 10:182. [PMID: 30899227 PMCID: PMC6416196 DOI: 10.3389/fphys.2019.00182] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Accepted: 02/14/2019] [Indexed: 12/30/2022] Open
Abstract
Optogenetic control of the heart is an emergent technology that offers unparalleled spatio-temporal control of cardiac dynamics via light-sensitive ion pumps and channels (opsins). This fast-evolving technique holds broad scope in both clinical and basic research setting. Combination of optogenetics with optical mapping of voltage or calcium fluorescent probes facilitates 'all-optical' electrophysiology, allowing precise optogenetic actuation of cardiac tissue with high spatio-temporal resolution imaging of action potential and calcium transient morphology and conduction patterns. In this review, we provide a synopsis of optogenetics and discuss in detail its use and compatibility with optical interrogation of cardiac electrophysiology. We briefly discuss the benefits of all-optical cardiac control and electrophysiological interrogation compared to traditional techniques, and describe mechanisms, unique features and limitations of optically induced cardiac control. In particular, we focus on state-of-the-art setup design, challenges in light delivery and filtering, and compatibility of opsins with fluorescent reporters used in optical mapping. The interaction of cardiac tissue with light, and physical and computational approaches to overcome the 'spectral congestion' that arises from the combination of optogenetics and optical mapping are discussed. Finally, we summarize recent preclinical work applications of combined cardiac optogenetics and optical mapping approach.
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Affiliation(s)
- Christopher O’Shea
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, United Kingdom
- School of Computer Science, University of Birmingham, Birmingham, United Kingdom
- EPSRC Centre for Doctoral Training in Physical Sciences for Health, School of Chemistry, University of Birmingham, Birmingham, United Kingdom
| | - Andrew P. Holmes
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, United Kingdom
- Institute of Clinical Sciences, University of Birmingham, Birmingham, United Kingdom
| | - James Winter
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Joao Correia
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Birmingham, United Kingdom
| | - Xianhong Ou
- Key Laboratory of Medical Electrophysiology of Ministry of Education, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease/Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Ruirui Dong
- Key Laboratory of Medical Electrophysiology of Ministry of Education, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease/Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Shicheng He
- Key Laboratory of Medical Electrophysiology of Ministry of Education, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease/Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Paulus Kirchhof
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, United Kingdom
- Department of Cardiology, UHB NHS Trust, Birmingham, United Kingdom
| | - Larissa Fabritz
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, United Kingdom
- Department of Cardiology, UHB NHS Trust, Birmingham, United Kingdom
| | - Kashif Rajpoot
- School of Computer Science, University of Birmingham, Birmingham, United Kingdom
| | - Davor Pavlovic
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, United Kingdom
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16
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O'Shea C, Holmes AP, Yu TY, Winter J, Wells SP, Correia J, Boukens BJ, De Groot JR, Chu GS, Li X, Ng GA, Kirchhof P, Fabritz L, Rajpoot K, Pavlovic D. ElectroMap: High-throughput open-source software for analysis and mapping of cardiac electrophysiology. Sci Rep 2019; 9:1389. [PMID: 30718782 PMCID: PMC6362081 DOI: 10.1038/s41598-018-38263-2] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 12/21/2018] [Indexed: 02/04/2023] Open
Abstract
The ability to record and analyse electrical behaviour across the heart using optical and electrode mapping has revolutionised cardiac research. However, wider uptake of these technologies is constrained by the lack of multi-functional and robustly characterised analysis and mapping software. We present ElectroMap, an adaptable, high-throughput, open-source software for processing, analysis and mapping of complex electrophysiology datasets from diverse experimental models and acquisition modalities. Key innovation is development of standalone module for quantification of conduction velocity, employing multiple methodologies, currently not widely available to researchers. ElectroMap has also been designed to support multiple methodologies for accurate calculation of activation, repolarisation, arrhythmia detection, calcium handling and beat-to-beat heterogeneity. ElectroMap implements automated signal segmentation, ensemble averaging and integrates optogenetic approaches. Here we employ ElectroMap for analysis, mapping and detection of pro-arrhythmic phenomena in silico, in cellulo, animal model and in vivo patient datasets. We anticipate that ElectroMap will accelerate innovative cardiac research and enhance the uptake, application and interpretation of mapping technologies leading to novel approaches for arrhythmia prevention.
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Affiliation(s)
- Christopher O'Shea
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
- EPSRC Centre for Doctoral Training in Physical Sciences for Health, School of Chemistry, University of Birmingham, Birmingham, UK
- School of Computer Science, University of Birmingham, Birmingham, UK
| | - Andrew P Holmes
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
- Institute of Clinical Sciences, University of Birmingham, Birmingham, UK
| | - Ting Y Yu
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
| | - James Winter
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
| | - Simon P Wells
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
- Department of Physiology, University of Melbourne, Melbourne, Australia
| | - Joao Correia
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Birmingham, UK
| | - Bastiaan J Boukens
- Amsterdam UMC, University of Amsterdam, Department of Anatomy and Physiology, Amsterdam, The Netherlands
| | - Joris R De Groot
- Amsterdam UMC, University of Amsterdam, Heart Center, Department of Cardiology, Amsterdam, The Netherlands
| | - Gavin S Chu
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK
| | - Xin Li
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - G Andre Ng
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK
| | - Paulus Kirchhof
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
- Department of Cardiology, UHB NHS Trust, Birmingham, UK
| | - Larissa Fabritz
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
- Department of Cardiology, UHB NHS Trust, Birmingham, UK
| | - Kashif Rajpoot
- School of Computer Science, University of Birmingham, Birmingham, UK.
| | - Davor Pavlovic
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK.
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Francis Stuart SD, Wang L, Woodard WR, Ng GA, Habecker BA, Ripplinger CM. Age-related changes in cardiac electrophysiology and calcium handling in response to sympathetic nerve stimulation. J Physiol 2018; 596:3977-3991. [PMID: 29938794 DOI: 10.1113/jp276396] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 06/22/2018] [Indexed: 12/16/2022] Open
Abstract
KEY POINTS Ageing results in changes to cardiac electrophysiology, Ca2+ handling, and β-adrenergic responsiveness. Sympathetic neurodegeneration also occurs with age, yet detailed action potential and Ca2+ handling responses to physiological sympathetic nerve stimulation (SNS) in the aged heart have not been assessed. Optical mapping in mouse hearts with intact sympathetic innervation revealed reduced responsiveness to SNS in the aged atria (assessed by heart rate) and aged ventricles (assessed by action potentials and Ca2+ transients). Sympathetic nerve density and noradrenaline content were reduced in aged ventricles, but noradrenaline content was preserved in aged atria. These results demonstrate that reduced responsiveness to SNS in the atria may be primarily due to decreased β-adrenergic receptor responsiveness, whereas reduced responsiveness to SNS in the ventricles may be primarily due to neurodegeneration. ABSTRACT The objective of this study was to determine how age-related changes in sympathetic structure and function impact cardiac electrophysiology and intracellular Ca2+ handling. Innervated hearts from young (3-4 months, YWT, n = 10) and aged (20-24 months, AGED, n = 11) female mice (C57Bl6) were optically mapped using the voltage (Vm ,)- and calcium (Ca2+ )-sensitive indicators Rh237 and Rhod2-AM. Sympathetic nerve stimulation (SNS) was performed at the spinal cord (T1-T3). β-Adrenergic responsiveness was assessed with isoproterenol (1 μM, ISO). Sympathetic nerve density and noradrenaline content were also quantified. Stimulation thresholds necessary to produce a defined increase in heart rate (HR) with SNS were higher in AGED vs. YWT hearts (5.4 ± 0.4 vs. 3.8 ± 0.4 Hz, P < 0.05). Maximal HR with SNS was lower in AGED vs. YWT (20.5 ± 3.41% vs. 73.0 ± 7.63% increase, P < 0.05). β-Adrenergic responsiveness of the atria (measured as percentage increase in HR with ISO) was decreased in AGED vs. YWT hearts (75.3 ± 22.5% vs. 148.5 ± 19.8%, P < 0.05). SNS significantly increased action potential duration (APD) in YWT but not AGED. Ca2+ transient durations and rise times were unchanged by SNS, yet AGED hearts had an increased susceptibility to Ca2+ alternans and ventricular arrhythmias. β-Adrenergic responsiveness of all ventricular parameters were similar between AGED and YWT. Sympathetic nerve density and noradrenaline content were decreased in the AGED ventricle, but not atria, compared to YWT. These data suggest that decreased responsiveness to SNS in the aged atria may be primarily due to decreased β-adrenergic responsiveness, whereas decreased responsiveness to SNS in the aged ventricles may be primarily due to nerve degeneration.
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Affiliation(s)
| | - Lianguo Wang
- Department of Pharmacology, University of California Davis, Davis, CA, USA
| | - William R Woodard
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR, USA
| | - G Andre Ng
- Department of Cardiovascular Sciences, University of Leicester, NIHR Leicester Biomedical Research Centre, Leicester, UK
| | - Beth A Habecker
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR, USA
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