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Medvedev RY, Afolabi SO, Turner DGP, Glukhov AV. Mechanisms of stretch-induced electro-anatomical remodeling and atrial arrhythmogenesis. J Mol Cell Cardiol 2024; 193:11-24. [PMID: 38797242 DOI: 10.1016/j.yjmcc.2024.05.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 05/15/2024] [Accepted: 05/21/2024] [Indexed: 05/29/2024]
Abstract
Atrial fibrillation (AF) is the most common cardiac rhythm disorder, often occurring in the setting of atrial distension and elevated myocardialstretch. While various mechano-electrochemical signal transduction pathways have been linked to AF development and progression, the underlying molecular mechanisms remain poorly understood, hampering AF therapies. In this review, we describe different aspects of stretch-induced electro-anatomical remodeling as seen in animal models and in patients with AF. Specifically, we focus on cellular and molecular mechanisms that are responsible for mechano-electrochemical signal transduction and the development of ectopic beats triggering AF from pulmonary veins, the most common source of paroxysmal AF. Furthermore, we describe structural changes caused by stretch occurring before and shortly after the onset of AF as well as during AF progression, contributing to longstanding forms of AF. We also propose mechanical stretch as a new dimension to the concept "AF begets AF", in addition to underlying diseases. Finally, we discuss the mechanisms of these electro-anatomical alterations in a search for potential therapeutic strategies and the development of novel antiarrhythmic drugs targeted at the components of mechano-electrochemical signal transduction not only in cardiac myocytes, but also in cardiac non-myocyte cells.
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Affiliation(s)
- Roman Y Medvedev
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA
| | - Saheed O Afolabi
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA; Department of Pharmacology and Therapeutics, University of Ilorin, Ilorin, Nigeria
| | - Daniel G P Turner
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA
| | - Alexey V Glukhov
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, USA.
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2
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Cao Q, Liu L, Hu Y, Cao S, Tan T, Huang X, Deng Q, Chen J, Guo R, Zhou Q. Low-intensity pulsed ultrasound of different intensities differently affects myocardial ischemia/reperfusion injury by modulating cardiac oxidative stress and inflammatory reaction. Front Immunol 2023; 14:1248056. [PMID: 37744362 PMCID: PMC10513435 DOI: 10.3389/fimmu.2023.1248056] [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: 06/26/2023] [Accepted: 08/23/2023] [Indexed: 09/26/2023] Open
Abstract
Introduction The prevalence of ischemic heart disease has reached pandemic levels worldwide. Early revascularization is currently the most effective therapy for ischemic heart diseases but paradoxically induces myocardial ischemia/reperfusion (MI/R) injury. Cardiac inflammatory reaction and oxidative stress are primarily involved in the pathology of MI/R injury. Low-intensity pulsed ultrasound (LIPUS) has been demonstrated to reduce cell injury by protecting against inflammatory reaction and oxidative stress in many diseases, including cardiovascular diseases, but rarely on MI/R injury. Methods This study was designed to clarify whether LIPUS alleviates MI/R injury by alleviating inflammatory reaction and oxidative stress. Simultaneously, we have also tried to confirm which intensity of the LIPUS might be more suitable to ameliorate the MI/R injury, as well as to clarify the signaling mechanisms. MI/R and simulated ischemia/reperfusion (SI/R) were respectively induced in Sprague Dawley rats and human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs). LIPUS treatment, biochemical measurements, cell death assay, estimation of cardiac oxidative stress and inflammatory reaction, and protein detections by western blotting were performed according to the protocol. Results In our study, both in vivo and in vitro, LIPUS of 0.1 W/cm2 (LIPUS0.1) and 0.5 W/cm2 (LIPUS0.5) make no significant difference in the cardiomyocytes under normoxic condition. Under the hypoxic condition, MI/R injury, inflammatory reaction, and oxidative stress were partially ameliorated by LIPUS0.5 but were significantly aggravated by LIPUS of 2.5 W/cm2 (LIPUS2.5) both in vivo and in vitro. The activation of the apoptosis signal-regulating kinase 1 (ASK1)/c-Jun N-terminal kinase (JNK) pathway in cardiomyocytes with MI/R injury was partly rectified LIPUS0.5 both in vivo and in vitro. Conclusion Our study firstly demonstrated that LIPUS of different intensities differently affects MI/R injury by regulating cardiac inflammatory reaction and oxidative stress. Modulations on the ASK1/JNK pathway are the signaling mechanism by which LIPUS0.5 exerts cardioprotective effects. LIPUS0.5 is promising for clinical translation in protecting against MI/R injury. This will be great welfare for patients suffering from MI/R injury.
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Affiliation(s)
- Quan Cao
- Department of Nephrology, Zhongnan Hospital of Wuhan University, Wuhan, China
- Echo Lab, Department of Ultrasound Imaging, Renmin Hospital of Wuhan University, Wuhan, China
| | - Lian Liu
- Department of Anesthesiology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Yugang Hu
- Echo Lab, Department of Ultrasound Imaging, Renmin Hospital of Wuhan University, Wuhan, China
| | - Sheng Cao
- Echo Lab, Department of Ultrasound Imaging, Renmin Hospital of Wuhan University, Wuhan, China
| | - Tuantuan Tan
- Echo Lab, Department of Ultrasound Imaging, Renmin Hospital of Wuhan University, Wuhan, China
| | - Xin Huang
- Echo Lab, Department of Ultrasound Imaging, Renmin Hospital of Wuhan University, Wuhan, China
| | - Qing Deng
- Echo Lab, Department of Ultrasound Imaging, Renmin Hospital of Wuhan University, Wuhan, China
| | - Jinling Chen
- Echo Lab, Department of Ultrasound Imaging, Renmin Hospital of Wuhan University, Wuhan, China
| | - Ruiqiang Guo
- Echo Lab, Department of Ultrasound Imaging, Renmin Hospital of Wuhan University, Wuhan, China
| | - Qing Zhou
- Echo Lab, Department of Ultrasound Imaging, Renmin Hospital of Wuhan University, Wuhan, China
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3
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Chen M, Qin Y, Fan WT, Yan J, Hong F, Huang WH, Liu YL. Three-Dimensional Stretchable Sensor-Hydrogel Integrated Platform for Cardiomyocyte Culture and Mechanotransduction Monitoring. Anal Chem 2023; 95:12859-12866. [PMID: 37589391 DOI: 10.1021/acs.analchem.3c02151] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/18/2023]
Abstract
Cardiomyocytes are responsible for generating contractile force to pump blood throughout the body and are very sensitive to mechanical forces and can initiate mechano-electric coupling and mechano-chemo-transduction. Remarkable progress has been made in constructing heart tissue by engineered three-dimensional (3D) culture models and in recording the electrical signals of cardiomyocytes. However, it remains a severe challenge for real-time acquiring of the transient biochemical information in cardiomyocyte mechano-chemo-transduction. Herein, we reported a multifunctional platform by integrating a 3D stretchable electrochemical sensor with collagen hydrogel for the culture, electrical stimulation, and electrochemical monitoring of cardiomyocytes. The 3D stretchable electrochemical sensor was prepared by assembling functionalized conductive polymer PEDOT:PSS on an elastic scaffold, which showed excellent electrochemical sensing performance and stability under mechanical deformations. The integration of a 3D stretchable electrochemical sensor with collagen hydrogel provided an in vivo-like microenvironment for cardiomyocyte culture and promoted cell orientation via in situ electrical stimulation. Furthermore, this multifunctional platform allowed real-time monitoring of stretch-induced H2O2 release from cardiomyocytes under their normal and pathological conditions, as well as pharmacological interventions.
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Affiliation(s)
- Ming Chen
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Yu Qin
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Wen-Ting Fan
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Jing Yan
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Feng Hong
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Wei-Hua Huang
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Yan-Ling Liu
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
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4
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Lother A, Kohl P. The heterocellular heart: identities, interactions, and implications for cardiology. Basic Res Cardiol 2023; 118:30. [PMID: 37495826 PMCID: PMC10371928 DOI: 10.1007/s00395-023-01000-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 07/17/2023] [Accepted: 07/17/2023] [Indexed: 07/28/2023]
Abstract
The heterocellular nature of the heart has been receiving increasing attention in recent years. In addition to cardiomyocytes as the prototypical cell type of the heart, non-myocytes such as endothelial cells, fibroblasts, or immune cells are coming more into focus. The rise of single-cell sequencing technologies enables identification of ever more subtle differences and has reignited the question of what defines a cell's identity. Here we provide an overview of the major cardiac cell types, describe their roles in homeostasis, and outline recent findings on non-canonical functions that may be of relevance for cardiology. We highlight modes of biochemical and biophysical interactions between different cardiac cell types and discuss the potential implications of the heterocellular nature of the heart for basic research and therapeutic interventions.
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Affiliation(s)
- Achim Lother
- Institute of Experimental and Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Freiburg, Albertstr. 25, 79104, Freiburg, Germany.
- Interdisciplinary Medical Intensive Care, Faculty of Medicine, Medical Center-University of Freiburg, University of Freiburg, Freiburg, Germany.
| | - Peter Kohl
- Institute for Experimental Cardiovascular Medicine, Faculty of Medicine, University Heart Center, University of Freiburg, Freiburg, Germany
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
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5
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A Three-Dimensional Engineered Cardiac In Vitro Model: Controlled Alignment of Cardiomyocytes in 3D Microphysiological Systems. Cells 2023; 12:cells12040576. [PMID: 36831243 PMCID: PMC9954012 DOI: 10.3390/cells12040576] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 02/05/2023] [Accepted: 02/08/2023] [Indexed: 02/17/2023] Open
Abstract
Cardiomyocyte alignment in myocardium tissue plays a significant role in the physiological, electrical, and mechanical functions of the myocardium. It remains, however, difficult to align cardiac cells in a 3D in vitro heart model. This paper proposes a simple method to align cells using microfabricated Polydimethylsiloxane (PDMS) grooves with large dimensions (of up to 350 µm in width), similar to the dimensions of trabeculae carneae, the smallest functional unit of the myocardium. Two cell groups were used in this work; first, H9c2 cells in combination with Nor10 cells for proof of concept, and second, neonatal cardiac cells to investigate the functionality of the 3D model. This model compared the patterned and nonpatterned 3D constructs, as well as the 2D cell cultures, with and without patterns. In addition to alignment, we assessed the functionality of our proposed 3D model by comparing beating rates between aligned and non-aligned structures. In order to assess the practicality of the model, the 3D aligned structures should be demonstrated to be detachable and alignable. This evaluation is crucial to the use of this 3D functional model in future studies related to drug screening, building blocks for tissue engineering, and as a heart-on-chip by integrating microfluidics.
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6
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Peyronnet R, Desai A, Edelmann JC, Cameron BA, Emig R, Kohl P, Dean D. Simultaneous assessment of radial and axial myocyte mechanics by combining atomic force microscopy and carbon fibre techniques. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210326. [PMID: 36189808 PMCID: PMC9527909 DOI: 10.1098/rstb.2021.0326] [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: 03/31/2022] [Accepted: 07/21/2022] [Indexed: 11/12/2022] Open
Abstract
Cardiomyocytes sense and shape their mechanical environment, contributing to its dynamics by their passive and active mechanical properties. While axial forces generated by contracting cardiomyocytes have been amply investigated, the corresponding radial mechanics remain poorly characterized. Our aim is to simultaneously monitor passive and active forces, both axially and radially, in cardiomyocytes freshly isolated from adult mouse ventricles. To do so, we combine a carbon fibre (CF) set-up with a custom-made atomic force microscope (AFM). CF allows us to apply stretch and to record passive and active forces in the axial direction. The AFM, modified for frontal access to fit in CF, is used to characterize radial cell mechanics. We show that stretch increases the radial elastic modulus of cardiomyocytes. We further find that during contraction, cardiomyocytes generate radial forces that are reduced, but not abolished, when cells are forced to contract near isometrically. Radial forces may contribute to ventricular wall thickening during contraction, together with the dynamic re-orientation of cells and sheetlets in the myocardium. This new approach for characterizing cell mechanics allows one to obtain a more detailed picture of the balance of axial and radial mechanics in cardiomyocytes at rest, during stretch, and during contraction. This article is part of the theme issue 'The cardiomyocyte: new revelations on the interplay between architecture and function in growth, health, and disease'.
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Affiliation(s)
- Rémi Peyronnet
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg – Bad Krozingen, University of Freiburg, 79110 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
- National Heart and Lung Institute, Imperial College London, London, UK
| | | | | | - Breanne A. Cameron
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg – Bad Krozingen, University of Freiburg, 79110 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
| | - Ramona Emig
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg – Bad Krozingen, University of Freiburg, 79110 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Peter Kohl
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg – Bad Krozingen, University of Freiburg, 79110 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79110 Freiburg, Germany
- National Heart and Lung Institute, Imperial College London, London, UK
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
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7
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Alim CC, Ko CY, Mira Hernandez J, Shen EY, Baidar S, Chen‐Izu Y, Bers DM, Bossuyt J. Nitrosylation of cardiac CaMKII at Cys290 mediates mechanical afterload-induced increases in Ca 2+ transient and Ca 2+ sparks. J Physiol 2022; 600:4865-4879. [PMID: 36227145 PMCID: PMC9827875 DOI: 10.1113/jp283427] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 09/30/2022] [Indexed: 01/12/2023] Open
Abstract
Cardiac mechanical afterload induces an intrinsic autoregulatory increase in myocyte Ca2+ dynamics and contractility to enhance contraction (known as the Anrep effect or slow force response). Our prior work has implicated both nitric oxide (NO) produced by NO synthase 1 (NOS1) and calcium/calmodulin-dependent protein kinase II (CaMKII) activity as required mediators of this form of mechano-chemo-transduction. To test whether a single S-nitrosylation site on CaMKIIδ (Cys290) mediates enhanced sarcoplasmic reticulum Ca2+ leak and afterload-induced increases in sarcoplasmic reticulum (SR) Ca2+ uptake and release, we created a novel CRISPR-based CaMKIIδ knock-in (KI) mouse with a Cys to Ala mutation at C290. These CaMKIIδ-C290A-KI mice exhibited normal cardiac morphometry and function, as well as basal myocyte Ca2+ transients (CaTs) and β-adrenergic responses. However, the NO donor S-nitrosoglutathione caused an acute increased Ca2+ spark frequency in wild-type (WT) myocytes that was absent in the CaMKIIδ-C290A-KI myocytes. Using our cell-in-gel system to exert multiaxial three-dimensional mechanical afterload on myocytes during contraction, we found that WT myocytes exhibited an afterload-induced increase in Ca2+ sparks and Ca2+ transient amplitude and rate of decline. These afterload-induced effects were prevented in both cardiac-specific CaMKIIδ knockout and point mutant CaMKIIδ-C290A-KI myocytes. We conclude that CaMKIIδ activation by S-nitrosylation at the C290 site is essential in mediating the intrinsic afterload-induced enhancement of myocyte SR Ca2+ uptake, release and Ca2+ transient amplitude (the Anrep effect). The data also indicate that NOS1 activation is upstream of S-nitrosylation at C290 of CaMKII, and that this molecular mechano-chemo-transduction pathway is beneficial in allowing the heart to increase contractility to limit the reduction in stroke volume when aortic pressure (afterload) is elevated. KEY POINTS: A novel CRISPR-based CaMKIIδ knock-in mouse was created in which kinase activation by S-nitrosylation at Cys290 (C290A) is prevented. How afterload affects Ca2+ signalling was measured in cardiac myocytes that were embedded in a hydrogel that imposes a three-dimensional afterload. This mechanical afterload induced an increase in Ca2+ transient amplitude and decay in wild-type myocytes, but not in cardiac-specific CaMKIIδ knockout or C290A knock-in myocytes. The CaMKIIδ-C290 S-nitrosylation site is essential for the afterload-induced enhancement of Ca2+ transient amplitude and Ca2+ sparks.
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Affiliation(s)
- Chidera C. Alim
- Department of PharmacologyUniversity of CaliforniaDavisCAUSA
| | | | - Juliana Mira Hernandez
- Department of PharmacologyUniversity of CaliforniaDavisCAUSA,Research Group in Veterinary MedicineSchool of Veterinary MedicineUniversity Corporation LasallistaCaldasAntioquiaColombia
| | - Erin Y. Shen
- Department of PharmacologyUniversity of CaliforniaDavisCAUSA
| | - Sonya Baidar
- Department of PharmacologyUniversity of CaliforniaDavisCAUSA
| | - Ye Chen‐Izu
- Department of PharmacologyUniversity of CaliforniaDavisCAUSA,Department of Biomedical EngineeringUniversity of CaliforniaDavisCAUSA,Department of Internal Medicine/CardiologyUniversity of CaliforniaDavisCAUSA
| | - Donald M. Bers
- Department of PharmacologyUniversity of CaliforniaDavisCAUSA
| | - Julie Bossuyt
- Department of PharmacologyUniversity of CaliforniaDavisCAUSA
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8
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Quinn TA, Kohl P. The Bainbridge effect: stretching our understanding of cardiac pacemaking for more than a century. J Physiol 2022; 600:4377-4379. [PMID: 36124849 DOI: 10.1113/jp283610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- T Alexander Quinn
- Department of Physiology and Biophysics, Dalhousie University, Halifax, Canada.,School of Biomedical Engineering, Dalhousie University, Halifax, Canada
| | - Peter Kohl
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg • Bad Krozingen and Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Faculty of Engineering, University of Freiburg, Freiburg, Germany
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9
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Kazemi-Lari MA, Shimkunas R, Jian Z, Hegyi B, Izu L, Shaw JA, Wineman AS, Chen-Izu Y. Modeling Cardiomyocyte Mechanics and Autoregulation of Contractility by Mechano-Chemo-Transduction Feedback. iScience 2022; 25:104667. [PMID: 35860762 PMCID: PMC9289640 DOI: 10.1016/j.isci.2022.104667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Revised: 05/22/2022] [Accepted: 06/20/2022] [Indexed: 11/30/2022] Open
Abstract
The heart pumps blood into circulation against vascular resistance and actively regulates the contractile force to compensate for mechanical load changes. Our experimental data show that cardiomyocytes have a mechano-chemo-transduction (MCT) mechanism that increases intracellular Ca2+ transient to enhance contractility in response to increased mechanical load. This study advances the cardiac excitation- Ca2+ signaling-contraction (E-C) coupling model on conceptual and technical fronts. First, we developed analytical and computational models to perform 3-dimensional mechanical analysis of cardiomyocytes contracting in a viscoelastic medium under mechanical load. Next, we proposed an MCT feedback loop in the E-C coupling dynamic system to shift the feedforward paradigm of cardiac E-C coupling to an autoregulation model. Our combined modeling and experimental studies reveal that MCT enables autoregulation of E-C coupling and contractility in single cardiomyocytes, which underlies the heart’s intrinsic autoregulation in compensatory response to load changes in order to maintain the stroke volume and cardiac output. Excitation-contraction (E-C) coupling has mechano-chemo-transduction (MCT) feedback MCT feedback enables autoregulation of E-C coupling when contracting under load Models for 3D mechanical analyses of cardiomyocytes contraction Shifts the paradigm of cardiac E-C coupling from feedforward to autoregulation model
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10
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Kamkin AG, Kamkina OV, Shim AL, Bilichenko A, Mitrokhin VM, Kazansky VE, Filatova TS, Abramochkin D, Mladenov MI. The role of activation of two different sGC binding sites by NO-dependent and NO-independent mechanisms in the regulation of SACs in rat ventricular cardiomyocytes. Physiol Rep 2022; 10:e15246. [PMID: 35384354 PMCID: PMC8981922 DOI: 10.14814/phy2.15246] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 03/09/2022] [Accepted: 03/09/2022] [Indexed: 04/18/2023] Open
Abstract
The mechanoelectrical feedback (MEF) mechanism in the heart that plays a significant role in the occurrence of arrhythmias, involves cation flux through cation nonselective stretch-activated channels (SACs). It is well known that nitric oxide (NO) can act as a regulator of MEF. Here we addressed the possibility of SAC's regulation along NO-dependent and NO-independent pathways, as well as the possibility of S-nitrosylation of SACs. In freshly isolated rat ventricular cardiomyocytes, using the patch-clamp method in whole-cell configuration, inward nonselective stretch-activated cation current ISAC was recorded through SACs, which occurs during dosed cell stretching. NO donor SNAP, α1-subunit of sGC activator BAY41-2272, sGC blocker ODQ, PKG blocker KT5823, PKG activator 8Br-cGMP, and S-nitrosylation blocker ascorbic acid, were employed. We concluded that the physiological concentration of NO in the cell is a necessary condition for the functioning of SACs. An increase in NO due to SNAP in an unstretched cell causes the appearance of a Gd3+ -sensitive nonselective cation current, an analog of ISAC , while in a stretched cell it eliminates ISAC . The NO-independent pathway of sGC activation of α subunit, triggered by BAY41-2272, is also important for the regulation of SACs. Since S-nitrosylation inhibitor completely abolishes ISAC , this mechanism occurs. The application of BAY41-2272 cannot induce ISAC in a nonstretched cell; however, the addition of SNAP on its background activates SACs, rather due to S-nitrosylation. ODQ eliminates ISAC , but SNAP added on the background of stretch increases ISAC in addition to ODQ. This may be a result of the lack of NO as a result of inhibition of NOS by metabolically modified ODQ. KT5823 reduces PKG activity and reduces SACs phosphorylation, leading to an increase in ISAC . 8Br-cGMP reduces ISAC by activating PKG and its phosphorylation. These results demonstrate a significant contribution of S-nitrosylation to the regulation of SACs.
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Affiliation(s)
- Andre G. Kamkin
- Department of PhysiologyPirogov Russian National Research Medical UniversityMoscowRussia
| | - Olga V. Kamkina
- Department of PhysiologyPirogov Russian National Research Medical UniversityMoscowRussia
| | - Andrey L. Shim
- Department of PhysiologyPirogov Russian National Research Medical UniversityMoscowRussia
| | - Andrey Bilichenko
- Department of PhysiologyPirogov Russian National Research Medical UniversityMoscowRussia
| | - Vadim M. Mitrokhin
- Department of PhysiologyPirogov Russian National Research Medical UniversityMoscowRussia
| | - Viktor E. Kazansky
- Department of PhysiologyPirogov Russian National Research Medical UniversityMoscowRussia
| | - Tatiana S. Filatova
- Department of PhysiologyPirogov Russian National Research Medical UniversityMoscowRussia
- Department of Human and Animal PhysiologyLomonosov Moscow State UniversityMoscowRussia
| | - Denis V. Abramochkin
- Department of PhysiologyPirogov Russian National Research Medical UniversityMoscowRussia
- Department of Human and Animal PhysiologyLomonosov Moscow State UniversityMoscowRussia
| | - Mitko I. Mladenov
- Department of PhysiologyPirogov Russian National Research Medical UniversityMoscowRussia
- Faculty of Natural Sciences and MathematicsInstitute of Biology, “Ss. Cyril and Methodius” UniversitySkopjeMacedonia
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11
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Mongirdienė A, Skrodenis L, Varoneckaitė L, Mierkytė G, Gerulis J. Reactive Oxygen Species Induced Pathways in Heart Failure Pathogenesis and Potential Therapeutic Strategies. Biomedicines 2022; 10:biomedicines10030602. [PMID: 35327404 PMCID: PMC8945343 DOI: 10.3390/biomedicines10030602] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 02/25/2022] [Accepted: 03/02/2022] [Indexed: 02/07/2023] Open
Abstract
With respect to structural and functional cardiac disorders, heart failure (HF) is divided into HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF). Oxidative stress contributes to the development of both HFrEF and HFpEF. Identification of a broad spectrum of reactive oxygen species (ROS)-induced pathways in preclinical models has provided new insights about the importance of ROS in HFrEF and HFpEF development. While current treatment strategies mostly concern neuroendocrine inhibition, recent data on ROS-induced metabolic pathways in cardiomyocytes may offer additional treatment strategies and targets for both of the HF forms. The purpose of this article is to summarize the results achieved in the fields of: (1) ROS importance in HFrEF and HFpEF pathophysiology, and (2) treatments for inhibiting ROS-induced pathways in HFrEF and HFpEF patients. ROS-producing pathways in cardiomyocytes, ROS-activated pathways in different HF forms, and treatment options to inhibit their action are also discussed.
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Affiliation(s)
- Aušra Mongirdienė
- Department of Biochemistry, Medical Academy, Lithuanian University of Health Sciences, Eiveniu str. 4, LT-50161 Kaunas, Lithuania
- Correspondence: or ; Tel.: +370-837361768
| | - Laurynas Skrodenis
- Medical Academy, Lithuanian University of Health Sciences, Mickevičiaus str. 9, LT-44307 Kaunas, Lithuania; (L.S.); (L.V.); (G.M.); (J.G.)
| | - Leila Varoneckaitė
- Medical Academy, Lithuanian University of Health Sciences, Mickevičiaus str. 9, LT-44307 Kaunas, Lithuania; (L.S.); (L.V.); (G.M.); (J.G.)
| | - Gerda Mierkytė
- Medical Academy, Lithuanian University of Health Sciences, Mickevičiaus str. 9, LT-44307 Kaunas, Lithuania; (L.S.); (L.V.); (G.M.); (J.G.)
| | - Justinas Gerulis
- Medical Academy, Lithuanian University of Health Sciences, Mickevičiaus str. 9, LT-44307 Kaunas, Lithuania; (L.S.); (L.V.); (G.M.); (J.G.)
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12
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Sato H, Nagano T, Satoh W, Kumasaka K, Shindoh C, Miura M. Roles of stretch-activated channels and NADPH oxidase 2 in the induction of twitch contraction by muscle stretching in rat ventricular muscle. Pflugers Arch 2022; 474:355-363. [PMID: 35066611 DOI: 10.1007/s00424-021-02657-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 12/13/2021] [Accepted: 12/14/2021] [Indexed: 11/28/2022]
Abstract
Mechano-electric feedback means that muscle stretching causes depolarization of membrane potential. We investigated whether muscle stretching induces action potential and twitch contraction with a threshold of sarcomere length (SL) and what roles stretch-activated channels (SACs) and stretch-activated NADPH oxidase (X-ROS signaling) play in the induction. Trabeculae were obtained from the right ventricles of rat hearts. Force, SL, and [Ca2+]i were measured. Various degrees of stretching from the SL of 2.0 μm were applied 0.5 s after the last stimulus of the electrical train with 0.4-s intervals for 7.5 s. The SLtwitch was defined as the minimal SL at which twitch contraction was induced by the stretching. Muscle stretching induced twitch contraction with a threshold of SL at 0.4-s stimulus intervals ([Ca2+]o = 0.7 mmol/L). The SLtwitch was not changed by increasing the stimulus intervals and [Ca2+]o and by adding 1 μmol/L isoproterenol. The SLtwitch was not changed by adding 10 μmol/L Gd3+, 100 μmol/L or 200 μmol/L streptomycin, and 5 μmol/L GsMTx4. The SLtwitch was not changed by adding 1 μmol/L ryanodine and 3 μmol/L diphenyleneiodonium chloride. In contrast, the SLtwitch was increased by elevating extracellular K+ from 5 to 10 mmol/L and by adding the stretching during the refractory period of membrane potential. The addition of the stretching-induced twitch contraction more frequently induced arrhythmias. These results suggest that muscle stretching can induce twitch contraction with a threshold of SL and concern the occurrence of arrhythmias and that SACs and X-ROS signaling play no roles in the induction.
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Affiliation(s)
- Haruka Sato
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Tsuyoshi Nagano
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Wakako Satoh
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Kazunori Kumasaka
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Chiyohiko Shindoh
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Masahito Miura
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan.
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13
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Huethorst E, Mortensen P, Simitev RD, Gao H, Pohjolainen L, Talman V, Ruskoaho H, Burton FL, Gadegaard N, Smith GL. Conventional rigid 2D substrates cause complex contractile signals in monolayers of human induced pluripotent stem cell-derived cardiomyocytes. J Physiol 2021; 600:483-507. [PMID: 34761809 PMCID: PMC9299844 DOI: 10.1113/jp282228] [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: 08/10/2021] [Accepted: 11/03/2021] [Indexed: 11/21/2022] Open
Abstract
Abstract Human induced pluripotent stem cell‐derived cardiomyocytes (hiPSC‐CM) in monolayers interact mechanically via cell–cell and cell–substrate adhesion. Spatiotemporal features of contraction were analysed in hiPSC‐CM monolayers (1) attached to glass or plastic (Young's modulus (E) >1 GPa), (2) detached (substrate‐free) and (3) attached to a flexible collagen hydrogel (E = 22 kPa). The effects of isoprenaline on contraction were compared between rigid and flexible substrates. To clarify the underlying mechanisms, further gene expression and computational studies were performed. HiPSC‐CM monolayers exhibited multiphasic contractile profiles on rigid surfaces in contrast to hydrogels, substrate‐free cultures or single cells where only simple twitch‐like time‐courses were observed. Isoprenaline did not change the contraction profile on either surface, but its lusitropic and chronotropic effects were greater in hydrogel compared with glass. There was no significant difference between stiff and flexible substrates in regard to expression of the stress‐activated genes NPPA and NPPB. A computational model of cell clusters demonstrated similar complex contractile interactions on stiff substrates as a consequence of cell‐to‐cell functional heterogeneity. Rigid biomaterial surfaces give rise to unphysiological, multiphasic contractions in hiPSC‐CM monolayers. Flexible substrates are necessary for normal twitch‐like contractility kinetics and interpretation of inotropic interventions.
![]() Key points Spatiotemporal contractility analysis of human induced pluripotent stem cell‐derived cardiomyocyte (hiPSC‐CM) monolayers seeded on conventional, rigid surfaces (glass or plastic) revealed the presence of multiphasic contraction patterns across the monolayer with a high variability, despite action potentials recorded in the same areas being identical. These multiphasic patterns are not present in single cells, in detached monolayers or in monolayers seeded on soft substrates such as a hydrogel, where only ‘twitch’‐like transients are observed. HiPSC‐CM monolayers that display a high percentage of regions with multiphasic contraction have significantly increased contractile duration and a decreased lusotropic drug response. There is no indication that the multiphasic contraction patterns are associated with significant activation of the stress‐activated NPPA or NPPB signalling pathways. A computational model of cell clusters supports the biological findings that the rigid surface and the differential cell–substrate adhesion underly multiphasic contractile behaviour of hiPSC‐CMs.
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Affiliation(s)
- Eline Huethorst
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK.,Division of Biomedical Engineering, James Watt School of Engineering, University of Glasgow, Glasgow, UK
| | - Peter Mortensen
- School of Mathematics and Statistics, University of Glasgow, Glasgow, UK
| | - Radostin D Simitev
- School of Mathematics and Statistics, University of Glasgow, Glasgow, UK
| | - Hao Gao
- School of Mathematics and Statistics, University of Glasgow, Glasgow, UK
| | - Lotta Pohjolainen
- Drug Research Program and Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Virpi Talman
- Drug Research Program and Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Heikki Ruskoaho
- Drug Research Program and Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Francis L Burton
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK
| | - Nikolaj Gadegaard
- Division of Biomedical Engineering, James Watt School of Engineering, University of Glasgow, Glasgow, UK
| | - Godfrey L Smith
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK
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14
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Small conductance calcium activated K + channel inhibitor decreases stretch induced vulnerability to atrial fibrillation. IJC HEART & VASCULATURE 2021; 37:100898. [PMID: 34746364 PMCID: PMC8554272 DOI: 10.1016/j.ijcha.2021.100898] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/05/2021] [Accepted: 10/16/2021] [Indexed: 12/11/2022]
Abstract
Background Atrial dilation is an important risk factor for atrial fibrillation (AF) and animal studies have found that acute atrial dilation shortens the atrial effective refractory period (AERP) and increases the risk of AF. Stretch activated ion channels (SACs) and calcium channels play a role in this. The expression profile and calcium dependent activation makes the small conductance calcium activated K+ channel (KCa2.x) a candidate for coupling stretch induced increases in intracellular calcium through K+-efflux and thereby shortening of atrial refractoriness. Objectives We hypothesized that KCa2.x channel inhibitors can prevent the stretch induced shortening of AERP and protect the heart from AF. Methods The effect of KCa2 channel inhibitor (N-(pyridin-2-yl)-4-(pyridin-2-yl)thiazol-2-amine (ICA) 1 µM) was investigated using the isolated perfused rabbit heart preparation. To stretch the left atrium (LA) a balloon was inserted and inflated. AERP and action potential duration (APD) were recorded before and after atrial stretch. AF was induced by burst pacing the LA at different degrees of atrial stretch. Results Stretching of the LA by increasing the balloon pressure from 0 to 20 mmHg shortened the AERP by 8.6 ± 1 ms. In comparison, the KCa2 inhibitor ICA significantly attenuated the stretch induced shortening of AERP to 2.5 ± 1.1 ms. Total AF duration increased linearly with atrial balloon pressure. This relationship was not found in the presence of ICA. ICA lowered the incidence of AF induction and total AF duration. Conclusion The KCa2 channel inhibitor ICA attenuates the acute stretch induced shortening of AERP and decreases stretch induced vulnerability to AF.
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15
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Emig R, Zgierski-Johnston CM, Timmermann V, Taberner AJ, Nash MP, Kohl P, Peyronnet R. Passive myocardial mechanical properties: meaning, measurement, models. Biophys Rev 2021; 13:587-610. [PMID: 34765043 PMCID: PMC8555034 DOI: 10.1007/s12551-021-00838-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 08/26/2021] [Indexed: 02/06/2023] Open
Abstract
Passive mechanical tissue properties are major determinants of myocardial contraction and relaxation and, thus, shape cardiac function. Tightly regulated, dynamically adapting throughout life, and affecting a host of cellular functions, passive tissue mechanics also contribute to cardiac dysfunction. Development of treatments and early identification of diseases requires better spatio-temporal characterisation of tissue mechanical properties and their underlying mechanisms. With this understanding, key regulators may be identified, providing pathways with potential to control and limit pathological development. Methodologies and models used to assess and mimic tissue mechanical properties are diverse, and available data are in part mutually contradictory. In this review, we define important concepts useful for characterising passive mechanical tissue properties, and compare a variety of in vitro and in vivo techniques that allow one to assess tissue mechanics. We give definitions of key terms, and summarise insight into determinants of myocardial stiffness in situ. We then provide an overview of common experimental models utilised to assess the role of environmental stiffness and composition, and its effects on cardiac cell and tissue function. Finally, promising future directions are outlined.
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Affiliation(s)
- Ramona Emig
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg, Bad Krozingen, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Callum M. Zgierski-Johnston
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg, Bad Krozingen, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Viviane Timmermann
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg, Bad Krozingen, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Andrew J. Taberner
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
- Department of Engineering Science, The University of Auckland, Auckland, New Zealand
| | - Martyn P. Nash
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
- Department of Engineering Science, The University of Auckland, Auckland, New Zealand
| | - Peter Kohl
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg, Bad Krozingen, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
- Faculty of Engineering, University of Freiburg, Freiburg, Germany
| | - Rémi Peyronnet
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg, Bad Krozingen, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
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16
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Körner A, Mosqueira M, Hecker M, Ullrich ND. Substrate Stiffness Influences Structural and Functional Remodeling in Induced Pluripotent Stem Cell-Derived Cardiomyocytes. Front Physiol 2021; 12:710619. [PMID: 34489730 PMCID: PMC8416903 DOI: 10.3389/fphys.2021.710619] [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: 05/16/2021] [Accepted: 07/26/2021] [Indexed: 01/01/2023] Open
Abstract
Novel treatment strategies for cardiac tissue regeneration are heading for the use of engineered cardiac tissue made from induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs). Despite the proven cardiogenic phenotype of these cells, a significant lack of structural and functional properties of mature myocytes prevents safe integration into the diseased heart. To date, maturation processes of cardiomyocytes remain largely unknown but may comprise biophysical cues from the immediate cell environment. Mechanosensing is one critical ability of cells to react to environmental changes. Accordingly, the surrounding substrate stiffness, comprised of extracellular matrix (ECM), cells, and growth surface, critically influences the myocyte's physiology, as known from deleterious remodeling processes in fibrotic hearts. Conversely, the mechanical properties during culture of iPSC-CMs may impact on their structural and functional maturation. Here, we tested the hypothesis that the environmental stiffness influences structural and functional properties of iPSC-CMs and investigated the effect of different substrate stiffnesses on cell contractility, excitation-contraction (EC) coupling, and intercellular coupling. Culture surfaces with defined stiffnesses ranging from rigid glass with 25GPa to PDMS of physiological softness were coated with ECM proteins and seeded with murine iPSC-CMs. Using confocal imaging, cardiac protein expression was assessed. Ca2+ handling and contractile properties were analyzed on different substrate stiffnesses. Intercellular coupling via gap junctions was investigated by fluorescence recovery after photobleaching (FRAP). Our data revealed greater organization of L-type Ca2+ channels and ryanodine receptors and increased EC-coupling gain, demonstrating structural and functional maturation in cells grown on soft surfaces. In addition, increased shortening and altered contraction dynamics revealed increased myofilament Ca2+ sensitivity in phase-plane loops. Moreover, connexin 43 expression was significantly increased in iPSC-CMs grown on soft surfaces leading to improved intercellular coupling. Taken together, our results demonstrate that soft surfaces with stiffnesses in the physiological range improve the expression pattern and interaction of cardiac proteins relevant for EC-coupling. In parallel, soft substrates influence contractile properties and improve intercellular coupling in iPSC-CMs. We conclude that the mechanical stiffness of the cell environment plays an important role in driving iPSC-CMs toward further maturation by inducing adaptive responses.
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Affiliation(s)
- Arlene Körner
- Division of Cardiovascular Physiology, Institute of Physiology and Pathophysiology, Heidelberg University, Heidelberg, Germany.,German Center for Cardiovascular Research (DZHK), Partner Site Heidelberg-Mannheim, Heidelberg, Germany
| | - Matias Mosqueira
- Division of Cardiovascular Physiology, Institute of Physiology and Pathophysiology, Heidelberg University, Heidelberg, Germany
| | - Markus Hecker
- Division of Cardiovascular Physiology, Institute of Physiology and Pathophysiology, Heidelberg University, Heidelberg, Germany.,German Center for Cardiovascular Research (DZHK), Partner Site Heidelberg-Mannheim, Heidelberg, Germany
| | - Nina D Ullrich
- Division of Cardiovascular Physiology, Institute of Physiology and Pathophysiology, Heidelberg University, Heidelberg, Germany.,German Center for Cardiovascular Research (DZHK), Partner Site Heidelberg-Mannheim, Heidelberg, Germany
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17
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Hegyi B, Shimkunas R, Jian Z, Izu LT, Bers DM, Chen-Izu Y. Mechanoelectric coupling and arrhythmogenesis in cardiomyocytes contracting under mechanical afterload in a 3D viscoelastic hydrogel. Proc Natl Acad Sci U S A 2021; 118:e2108484118. [PMID: 34326268 PMCID: PMC8346795 DOI: 10.1073/pnas.2108484118] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The heart pumps blood against the mechanical afterload from arterial resistance, and increased afterload may alter cardiac electrophysiology and contribute to life-threatening arrhythmias. However, the cellular and molecular mechanisms underlying mechanoelectric coupling in cardiomyocytes remain unclear. We developed an innovative patch-clamp-in-gel technology to embed cardiomyocytes in a three-dimensional (3D) viscoelastic hydrogel that imposes an afterload during regular myocyte contraction. Here, we investigated how afterload affects action potentials, ionic currents, intracellular Ca2+ transients, and cell contraction of adult rabbit ventricular cardiomyocytes. We found that afterload prolonged action potential duration (APD), increased transient outward K+ current, decreased inward rectifier K+ current, and increased L-type Ca2+ current. Increased Ca2+ entry caused enhanced Ca2+ transients and contractility. Moreover, elevated afterload led to discordant alternans in APD and Ca2+ transient. Ca2+ alternans persisted under action potential clamp, indicating that the alternans was Ca2+ dependent. Furthermore, all these afterload effects were significantly attenuated by inhibiting nitric oxide synthase 1 (NOS1). Taken together, our data reveal a mechano-chemo-electrotransduction (MCET) mechanism that acutely transduces afterload through NOS1-nitric oxide signaling to modulate the action potential, Ca2+ transient, and contractility. The MCET pathway provides a feedback loop in excitation-Ca2+ signaling-contraction coupling, enabling autoregulation of contractility in cardiomyocytes in response to afterload. This MCET mechanism is integral to the individual cardiomyocyte (and thus the heart) to intrinsically enhance its contractility in response to the load against which it has to do work. While this MCET is largely compensatory for physiological load changes, it may also increase susceptibility to arrhythmias under excessive pathological loading.
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Affiliation(s)
- Bence Hegyi
- Department of Pharmacology, University of California, Davis, CA 95616
| | - Rafael Shimkunas
- Department of Pharmacology, University of California, Davis, CA 95616
- Department of Biomedical Engineering, University of California, Davis, CA 95616
| | - Zhong Jian
- Department of Pharmacology, University of California, Davis, CA 95616
| | - Leighton T Izu
- Department of Pharmacology, University of California, Davis, CA 95616
| | - Donald M Bers
- Department of Pharmacology, University of California, Davis, CA 95616
| | - Ye Chen-Izu
- Department of Pharmacology, University of California, Davis, CA 95616;
- Department of Biomedical Engineering, University of California, Davis, CA 95616
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of California, Davis, CA 95616
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18
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Weissman D, Maack C. Redox signaling in heart failure and therapeutic implications. Free Radic Biol Med 2021; 171:345-364. [PMID: 34019933 DOI: 10.1016/j.freeradbiomed.2021.05.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/17/2021] [Accepted: 05/03/2021] [Indexed: 12/13/2022]
Abstract
Heart failure is a growing health burden worldwide characterized by alterations in excitation-contraction coupling, cardiac energetic deficit and oxidative stress. While current treatments are mostly limited to antagonization of neuroendocrine activation, more recent data suggest that also targeting metabolism may provide substantial prognostic benefit. However, although in a broad spectrum of preclinical models, oxidative stress plays a causal role for the development and progression of heart failure, no treatment that targets reactive oxygen species (ROS) directly has entered the clinical arena yet. In the heart, ROS derive from various sources, such as NADPH oxidases, xanthine oxidase, uncoupled nitric oxide synthase and mitochondria. While mitochondria are the primary source of ROS in the heart, communication between different ROS sources may be relevant for physiological signalling events as well as pathologically elevated ROS that deteriorate excitation-contraction coupling, induce hypertrophy and/or trigger cell death. Here, we review the sources of ROS in the heart, the modes of pathological activation of ROS formation as well as therapeutic approaches that may target ROS specifically in mitochondria.
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Affiliation(s)
- David Weissman
- Comprehensive Heart Failure Center (CHFC), University Clinic Würzburg, Würzburg, Germany
| | - Christoph Maack
- Comprehensive Heart Failure Center (CHFC), University Clinic Würzburg, Würzburg, Germany; Department of Internal Medicine 1, University Clinic Würzburg, Würzburg, Germany.
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19
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Kazemi-Lari MA, Shaw JA, Wineman AS, Shimkunas R, Jian Z, Hegyi B, Izu L, Chen-Izu Y. A viscoelastic Eshelby inclusion model and analysis of the Cell-in-Gel system. INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE 2021; 165:103489. [PMID: 34629507 PMCID: PMC8500226 DOI: 10.1016/j.ijengsci.2021.103489] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We develop a viscoelastic generalization of the elastic Eshelby inclusion solution, where the inclusion and surrounding matrix are two different viscoelastic solids and the inclusion's eigenstrain is a time-periodic oscillatory input. The solution exploits the Correspondence Principle of Linear Viscoelasticity and a Discrete Fourier Transform to efficiently capture the steady-state oscillatory behavior of the 3-D mechanical fields. The approach is illustrated here in the context of the recently-developed in vitro Cell-in-Gel system, where an isolated live cardiomyocyte (the inclusion) is paced to contract periodically within a soft hydrogel (the matrix), for the purpose of studying the effect of mechanical load on biochemical signals that regulate contractility. The addition of viscoelasticity improves the fidelity of our previous elastic Eshelby inclusion analysis of the Cell-in-Gel system by accounting for the time-varying fields and the resulting hysteresis and dissipated mechanical energy. This mathematical model is used to study the parametric sensitivities of the relative stiffness of the inclusion, the inclusion's aspect ratio (slenderness), and the cross-link density of the hydrogel matrix.
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Affiliation(s)
| | - John A Shaw
- Department of Aerospace Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Alan S Wineman
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Rafael Shimkunas
- Pharmacology and Biomedical Engineering Departments, University of California, Davis, CA 95616, USA
| | - Zhong Jian
- Pharmacology and Biomedical Engineering Departments, University of California, Davis, CA 95616, USA
| | - Bence Hegyi
- Pharmacology and Biomedical Engineering Departments, University of California, Davis, CA 95616, USA
| | - Leighton Izu
- Pharmacology and Biomedical Engineering Departments, University of California, Davis, CA 95616, USA
| | - Ye Chen-Izu
- Pharmacology and Biomedical Engineering Departments, University of California, Davis, CA 95616, USA
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20
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Izu L, Shimkunas R, Jian Z, Hegyi B, Kazemi-Lari M, Baker A, Shaw J, Banyasz T, Chen-Izu Y. Emergence of Mechano-Sensitive Contraction Autoregulation in Cardiomyocytes. Life (Basel) 2021; 11:503. [PMID: 34072584 PMCID: PMC8227646 DOI: 10.3390/life11060503] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/26/2021] [Accepted: 05/27/2021] [Indexed: 12/24/2022] Open
Abstract
The heart has two intrinsic mechanisms to enhance contractile strength that compensate for increased mechanical load to help maintain cardiac output. When vascular resistance increases the ventricular chamber initially expands causing an immediate length-dependent increase of contraction force via the Frank-Starling mechanism. Additionally, the stress-dependent Anrep effect slowly increases contraction force that results in the recovery of the chamber volume towards its initial state. The Anrep effect poses a paradox: how can the cardiomyocyte maintain higher contractility even after the cell length has recovered its initial length? Here we propose a surface mechanosensor model that enables the cardiomyocyte to sense different mechanical stresses at the same mechanical strain. The cell-surface mechanosensor is coupled to a mechano-chemo-transduction feedback mechanism involving three elements: surface mechanosensor strain, intracellular Ca2+ transient, and cell strain. We show that in this simple yet general system, contractility autoregulation naturally emerges, enabling the cardiomyocyte to maintain contraction amplitude despite changes in a range of afterloads. These nontrivial model predictions have been experimentally confirmed. Hence, this model provides a new conceptual framework for understanding the contractility autoregulation in cardiomyocytes, which contributes to the heart's intrinsic adaptivity to mechanical load changes in health and diseases.
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Affiliation(s)
- Leighton Izu
- Department of Pharmacology, University of California, Davis, CA 95616, USA; (R.S.); (Z.J.); (B.H.); (M.K.-L.); (T.B.); (Y.C.-I.)
| | - Rafael Shimkunas
- Department of Pharmacology, University of California, Davis, CA 95616, USA; (R.S.); (Z.J.); (B.H.); (M.K.-L.); (T.B.); (Y.C.-I.)
| | - Zhong Jian
- Department of Pharmacology, University of California, Davis, CA 95616, USA; (R.S.); (Z.J.); (B.H.); (M.K.-L.); (T.B.); (Y.C.-I.)
| | - Bence Hegyi
- Department of Pharmacology, University of California, Davis, CA 95616, USA; (R.S.); (Z.J.); (B.H.); (M.K.-L.); (T.B.); (Y.C.-I.)
| | - Mohammad Kazemi-Lari
- Department of Pharmacology, University of California, Davis, CA 95616, USA; (R.S.); (Z.J.); (B.H.); (M.K.-L.); (T.B.); (Y.C.-I.)
| | - Anthony Baker
- Department of Medicine, University of California, San Francisco, CA 94121, USA;
| | - John Shaw
- Department of Aerospace Engineering, University of Michigan, Ann Arbor, MI 48109, USA;
| | - Tamas Banyasz
- Department of Pharmacology, University of California, Davis, CA 95616, USA; (R.S.); (Z.J.); (B.H.); (M.K.-L.); (T.B.); (Y.C.-I.)
- Department of Physiology, University of Debrecen, 4032 Debrecen, Hungary
| | - Ye Chen-Izu
- Department of Pharmacology, University of California, Davis, CA 95616, USA; (R.S.); (Z.J.); (B.H.); (M.K.-L.); (T.B.); (Y.C.-I.)
- Department of Biomedical Engineering, University of California, Davis, CA 95616, USA
- Department of Internal Medicine, Division of Cardiology, University of California, Davis, CA 95616, USA
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21
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Li J, Jiang M, Su M, Tian L, Shi W, Yu C. Stretchable and Transparent Electrochemical Sensor Based on Nanostructured Au on Carbon Nanotube Networks for Real-Time Analysis of H 2O 2 Release from Cells. Anal Chem 2021; 93:6723-6730. [PMID: 33891403 DOI: 10.1021/acs.analchem.1c00336] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Various electrochemical biosensors have been developed for direct and real-time recording of biomolecules released from living cells. However, since these traditional electrodes are commonly rigid and nonflexible, in situ monitoring of biochemical signals while cell deformation occurs remains a great challenge. Herein, we report a facile approach for the development of a stretchable and transparent electrochemical cell-sensing platform based on Au nanostructures (nano-Au) and carbon nanotube (CNT) films embedded in PDMS (nano-Au/CNTs/PDMS). The sandwich-like nanostructured network of nano-Au/CNTs endows the sensor with excellent mechanical stability and electrochemical performance. The obtained nano-Au/CNTs/PDMS electrode displays desired performance for H2O2 detection with a wide linear range (20 nM-25.8 μM) and low detection limit (8 nM). Owing to good biocompatibility and flexibility, HeLa and human umbilical vein endothelial cells can be directly cultured on the electrode and real-time monitoring of H2O2 release from cells under their stretched state was realized. The proposed strategy demonstrated in this work provides an effective way for design of stretchable sensors and more opportunities for sensing biomolecules from mechanically sensitive cells.
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Affiliation(s)
- Jing Li
- School of Public Health, Nantong University, Nantong 226019, P. R. China
| | - Mengyuan Jiang
- School of Public Health, Nantong University, Nantong 226019, P. R. China
| | - Mengjie Su
- School of Public Health, Nantong University, Nantong 226019, P. R. China
| | - Liang Tian
- School of Public Health, Nantong University, Nantong 226019, P. R. China
| | - Weishan Shi
- School of Public Health, Nantong University, Nantong 226019, P. R. China
| | - Chunmei Yu
- School of Public Health, Nantong University, Nantong 226019, P. R. China
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Shimkunas R, Hegyi B, Jian Z, Shaw JA, Kazemi-Lari MA, Mitra D, Leach JK, Li X, Jaradeh M, Balardi N, Chen YJ, Escobar AL, Baker AJ, Bossuyt J, Banyasz T, Chiamvimonvat N, Lam KS, Bers DM, Izu LT, Chen-Izu Y. Mechanical Load Regulates Excitation-Ca 2+ Signaling-Contraction in Cardiomyocyte. Circ Res 2021; 128:772-774. [PMID: 33601939 PMCID: PMC7979518 DOI: 10.1161/circresaha.120.318570] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Rafael Shimkunas
- Pharmacology, University of California, Davis, CA 95616, USA
- Biomedical Engineering, University of California, Davis, CA 95616, USA
| | - Bence Hegyi
- Pharmacology, University of California, Davis, CA 95616, USA
| | - Zhong Jian
- Pharmacology, University of California, Davis, CA 95616, USA
| | - John A. Shaw
- Aerospace Engineering, University of Michigan, Ann Arbor, MI, USA
| | | | - Debika Mitra
- Biomedical Engineering, University of California, Davis, CA 95616, USA
| | - J. Kent Leach
- Biomedical Engineering, University of California, Davis, CA 95616, USA
| | - Xiaocen Li
- Biochemistry and Molecular Medicine, University of California, Davis, CA 95616, USA
| | - Mark Jaradeh
- Pharmacology, University of California, Davis, CA 95616, USA
| | | | - Yi-Je Chen
- Pharmacology, University of California, Davis, CA 95616, USA
| | | | | | - Julie Bossuyt
- Pharmacology, University of California, Davis, CA 95616, USA
| | - Tamas Banyasz
- Pharmacology, University of California, Davis, CA 95616, USA
- Physiology, University of Debrecen, Hungary
| | | | - Kit S. Lam
- Biochemistry and Molecular Medicine, University of California, Davis, CA 95616, USA
| | - Donald M. Bers
- Pharmacology, University of California, Davis, CA 95616, USA
| | - Leighton T. Izu
- Pharmacology, University of California, Davis, CA 95616, USA
| | - Ye Chen-Izu
- Pharmacology, University of California, Davis, CA 95616, USA
- Biomedical Engineering, University of California, Davis, CA 95616, USA
- Internal Medicine, University of California, Davis, CA 95616, USA
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23
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Harris SP. Making waves: A proposed new role for myosin-binding protein C in regulating oscillatory contractions in vertebrate striated muscle. J Gen Physiol 2020; 153:211574. [PMID: 33275758 PMCID: PMC7721898 DOI: 10.1085/jgp.202012729] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Myosin-binding protein C (MyBP-C) is a critical regulator of muscle performance that was first identified through its strong binding interactions with myosin, the force-generating protein of muscle. Almost simultaneously with its discovery, MyBP-C was soon found to bind to actin, the physiological catalyst for myosin’s activity. However, the two observations posed an apparent paradox, in part because interactions of MyBP-C with myosin were on the thick filament, whereas MyBP-C interactions with actin were on the thin filament. Despite the intervening decades since these initial discoveries, it is only recently that the dual binding modes of MyBP-C are becoming reconciled in models that place MyBP-C at a central position between actin and myosin, where MyBP-C alternately stabilizes a newly discovered super-relaxed state (SRX) of myosin on thick filaments in resting muscle and then prolongs the “on” state of actin on thin filaments in active muscle. Recognition of these dual, alternating functions of MyBP-C reveals how it is central to the regulation of both muscle contraction and relaxation. The purpose of this Viewpoint is to briefly summarize the roles of MyBP-C in binding to myosin and actin and then to highlight a possible new role for MyBP-C in inducing and damping oscillatory waves of contraction and relaxation. Because the contractile waves bear similarity to cycles of contraction and relaxation in insect flight muscles, which evolved for fast, energetically efficient contraction, the ability of MyBP-C to damp so-called spontaneous oscillatory contractions (SPOCs) has broad implications for previously unrecognized regulatory mechanisms in vertebrate striated muscle. While the molecular mechanisms by which MyBP-C can function as a wave maker or a wave breaker are just beginning to be explored, it is likely that MyBP-C dual interactions with both myosin and actin will continue to be important for understanding the new functions of this enigmatic protein.
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24
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Piccus R, Brayson D. The nuclear envelope: LINCing tissue mechanics to genome regulation in cardiac and skeletal muscle. Biol Lett 2020; 16:20200302. [PMID: 32634376 DOI: 10.1098/rsbl.2020.0302] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Regulation of the genome is viewed through the prism of gene expression, DNA replication and DNA repair as controlled through transcription, chromatin compartmentalisation and recruitment of repair factors by enzymes such as DNA polymerases, ligases, acetylases, methylases and cyclin-dependent kinases. However, recent advances in the field of muscle cell physiology have also shown a compelling role for 'outside-in' biophysical control of genomic material through mechanotransduction. The crucial hub that transduces these biophysical signals is called the Linker of Nucleoskeleton and Cytoskeleton (LINC). This complex is embedded across the nuclear envelope, which separates the nucleus from the cytoplasm. How the LINC complex operates to mechanically regulate the many functions of DNA is becoming increasingly clear, and recent advances have provided exciting insight into how this occurs in cells from mechanically activated tissues such as skeletal and cardiac muscle. Nevertheless, there are still some notable shortcomings in our understanding of these processes and resolving these will likely help us understand how muscle diseases manifest at the level of the genome.
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Affiliation(s)
- Rachel Piccus
- Centre for Human and Applied Physiological Sciences, King's College London, London SE1 1UL, UK
| | - Daniel Brayson
- School of Cardiovascular Medicine and Sciences, King's College London, London SE5 9NU, UK.,Molecular Neurosciences, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK
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25
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Kuhtz-Buschbeck JP, Schaefer J, Wilder N, Wolze WT. The origin of the heartbeat and theories of muscle contraction. Physiological concepts and conflicts in the 19th century. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2020; 159:3-9. [PMID: 32622835 DOI: 10.1016/j.pbiomolbio.2020.05.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 04/27/2020] [Accepted: 05/28/2020] [Indexed: 11/19/2022]
Abstract
The origin of the incessant rhythmical heartbeat and the mechanism of muscle contraction have fascinated scientists over centuries. This short review outlines physiological explanations that were discussed in the 19th century starting with Albrecht von Haller (1708-1777), an 18th century physiologist who proposed that the heart has an intrinsic irritability. He argued that under normal conditions the inflow of blood stimulates the heart muscle to contract by mechanical touch and distension. Johannes Müller (1800-1858, physiologist in Bonn and Berlin) contended that the influence of the sympathetic nerve, specifically the activity of intracardiac ganglia, is the foremost cause of the heartbeat. Walter H. Gaskell and Theodor Engelmann (physiologists in Cambridge and Utrecht, respectively) independently criticized this neurogenic theory. They reported experimental evidence that supported the myogenic theory of the origin of the heartbeat, which has been accepted since about 1900. The concept of cardiac mechano-sensitivity, which can be traced back to A. von Haller, is currently resurging. Concerning mechanisms of contraction, Edward A. Schäfer (1850-1935), histologist and physiologist in Edinburgh, described differences between cardiac and skeletal muscle and coined the term sarcomere. Based on microscopic studies of cross-striated muscle, Schäfer outlined a detailed and plausible mechanism of muscle contraction in 1892. He put forward that during muscle shortening the "clear part of the muscle substance" (actin) might pass into longitudinal canals, which exist between the "sarcous elements" (myosin). His model foresaw fundamental elements of the sliding filament model, which was discovered by the Huxleys about 60 years later.
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Affiliation(s)
| | - Jochen Schaefer
- International Institute for Theoretical Cardiology, Kiel, Germany
| | - Nicolaus Wilder
- Institut für Pädagogik, Christian-Albrechts-Universität Kiel, Germany
| | - Wilhelm T Wolze
- Zentrum für konstruktive Erziehungswissenschaften, Christian-Albrechts-Universität Kiel, Germany
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26
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Bers DM, Kohl P, Chen-Izu Y. Mechanics and energetics in cardiac arrhythmias and heart failure. J Physiol 2020; 598:1275-1277. [PMID: 31998965 DOI: 10.1113/jp279385] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Affiliation(s)
- Donald M Bers
- Department of Pharmacology and Cardiovascular Research Institute, University of California, Davis, CA, USA
| | - Peter Kohl
- Institute for Experimental Cardiovascular Medicine, University Heart Centre, and Faculty of Medicine, University of Freiburg, Freiburg, D-79110, Germany
| | - Ye Chen-Izu
- Department of Pharmacology and Cardiovascular Research Institute, University of California, Davis, CA, USA
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