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Mitrokhin V, Bilichenko A, Kazanski V, Schobik R, Shileiko S, Revkova V, Kalsin V, Kamkina O, Kamkin A, Mladenov M. Transcriptomic profile of the mechanosensitive ion channelome in human cardiac fibroblasts. Exp Biol Med (Maywood) 2023; 248:2341-2350. [PMID: 38158807 PMCID: PMC10903254 DOI: 10.1177/15353702231218488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 09/27/2023] [Indexed: 01/03/2024] Open
Abstract
Human cardiac fibroblasts (HCFs) have mRNA transcripts that encode different mechanosensitive ion channels and channel regulatory proteins whose functions are not known yet. The primary goal of this work was to define the mechanosensitive ion channelome of HCFs. The most common type of cationic channel is the transient receptor potential (TRP) family, which is followed by the TWIK-related K+ channel (TREK), transmembrane protein 63 (TMEM63), and PIEZO channel (PIEZO) families. In the sodium-dependent NON-voltage-gated channel (SCNN) subfamily, only SCNN1D was shown to be highly expressed. Particular members of the acid-sensing ion channel (ASIC) (ASIC1 and ASIC3) subfamilies were also significantly expressed. The transcripts per kilobase million (TPMs) for Piezo 2 were almost 100 times less abundant than those for Piezo 1. The tandem of P domains in a weak inward rectifying K+ channel (TWIK)-2 channel, TWIK-related acid-sensitive K+ channel (TASK)-5, TASK-1, and the TWIK-related K1 (TREK-1) channel were the four most prevalent types in the K2P subfamily. The highest expression in the TRPP subfamily was found for PKD2 and PKD1, while in the TRPM subfamily, it was found for TRPM4, TRPM7, and TRPM3. TRPV2, TRPV4, TRPV3, and TRPV6 (all members of the TRPV subfamily) were also substantially expressed. A strong expression of the TRPC1, TRPC4, TRPC6, and TRPC2 channels and all members of the TRPML subfamily (MCOLN1, MCOLN2, and MCOLN3) was also shown. In terms of the transmembrane protein 16 (TMEM16) family, the HCFs demonstrated significant expression of the TMEM16H, TMEM16F, TMEM16J, TMEM16A, and TMEM16G channels. TMC3 is the most expressed channel in HCFs of all known members of the transmembrane channel-like protein (TMC) family. This analysis of the mechanosensitive ionic channel transcriptome in HCFs: (1) agrees with previously documented findings that all currently identified mechanosensitive channels play a significant and well recognized physiological function in elucidating the mechanosensitive characteristics of HCFs; (2) supports earlier preliminary reports that point to the most common expression of the TRP mechanosensitive family in HCFs; and (3) points to other new mechanosensitive channels (TRPC1, TRPC2, TWIK-2, TMEM16A, ASIC1, and ASIC3).
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Affiliation(s)
- Vadim Mitrokhin
- Department of Physiology, Pirogov Russian National Research Medical University, Moscow 117997, Russia
| | - Andrei Bilichenko
- Department of Physiology, Pirogov Russian National Research Medical University, Moscow 117997, Russia
| | - Viktor Kazanski
- Department of Physiology, Pirogov Russian National Research Medical University, Moscow 117997, Russia
| | - Roman Schobik
- Department of Physiology, Pirogov Russian National Research Medical University, Moscow 117997, Russia
| | - Stanislav Shileiko
- Department of Physiology, Pirogov Russian National Research Medical University, Moscow 117997, Russia
| | - Veronika Revkova
- Department of Physiology, Pirogov Russian National Research Medical University, Moscow 117997, Russia
| | - Vladimir Kalsin
- Department of Physiology, Pirogov Russian National Research Medical University, Moscow 117997, Russia
| | - Olga Kamkina
- Department of Physiology, Pirogov Russian National Research Medical University, Moscow 117997, Russia
| | - Andre Kamkin
- Department of Physiology, Pirogov Russian National Research Medical University, Moscow 117997, Russia
| | - Mitko Mladenov
- Department of Physiology, Pirogov Russian National Research Medical University, Moscow 117997, Russia
- Institute of Biology, Faculty of Natural Sciences and Mathematics, Ss. Cyril and Methodius University in Skopje, 1000 Skopje, North Macedonia
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2
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Dickey GJ, Bian K, Islam SU, Khan HR, Rohr S, Mao H. Advancing Commotio cordis Safety Standards Using the Total Human Models for Safety (THUMS). Ann Biomed Eng 2023; 51:2070-2085. [PMID: 37227601 DOI: 10.1007/s10439-023-03235-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 05/02/2023] [Indexed: 05/26/2023]
Abstract
Commotio cordis is one of the leading causes of sudden cardiac death in youth baseball. Currently, there are chest protector regulations regarding the prevention of Commotio cordis in baseball and lacrosse; however, they are not fully optimized. For the advancement of Commotio cordis safety, it is vital to include various age groups and a variety of impact angles in the testing process. This study employed finite element models and simulated Commotio cordis-inducing baseball collisions for different velocities, impact angles, and age groups. Commotio cordis risk response was characterized in terms of left ventricular strain and pressure, chest band and rib deformation, and force from impact. Normalized rib and chest band deformation when correlated with left ventricular strain resulted in R2 = 0.72, and R2 = 0.76, while left ventricular pressure resulted in R2 = 0.77, R2 = 0.68 across all velocities and impact angles in the child models. By contrast, the resultant reaction force risk metric as used by the National Operating Committee on Standards for Athletic Equipment (NOCSAE) demonstrated a correlation of R2 = 0.20 in the child models to ventricular strain, while illustrating a correlation to pressure of R2 = 0.74. When exploring future revisions to Commotio cordis safety requirements, the inclusion of deformation-related risk metrics at the level of the left ventricle should be considered.
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Affiliation(s)
- Grant James Dickey
- School of Biomedical Engineering, University of Western Ontario, London, Canada
| | - Kewei Bian
- Department of Mechanical and Materials Engineering, Faculty of Engineering, University of Western Ontario, London, Canada
| | - Sakib Ul Islam
- Department of Mechanical and Materials Engineering, Faculty of Engineering, University of Western Ontario, London, Canada
| | - Habib R Khan
- Division of Cardiology, Department of Medicine, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Canada
| | - Stephan Rohr
- Department of Physiology, University of Bern, Bern, Switzerland
| | - Haojie Mao
- School of Biomedical Engineering, University of Western Ontario, London, Canada.
- Department of Mechanical and Materials Engineering, Faculty of Engineering, University of Western Ontario, London, Canada.
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Wagner KD. Editorial (Preface) "Cells/Cells of the Cardiovascular System-Editorial Highlights 2020-2021: The Book Selection". Cells 2022; 11:cells11233898. [PMID: 36497157 PMCID: PMC9735509 DOI: 10.3390/cells11233898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 12/01/2022] [Indexed: 12/12/2022] Open
Abstract
This introduction provides a preface to the section on "Cells of the Cardiovascular System" in the book entitled "Editor's Choice Articles in 2020-2021" [...].
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Husti Z, Varró A, Baczkó I. Arrhythmogenic Remodeling in the Failing Heart. Cells 2021; 10:cells10113203. [PMID: 34831426 PMCID: PMC8623396 DOI: 10.3390/cells10113203] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 11/05/2021] [Accepted: 11/11/2021] [Indexed: 12/12/2022] Open
Abstract
Chronic heart failure is a clinical syndrome with multiple etiologies, associated with significant morbidity and mortality. Cardiac arrhythmias, including ventricular tachyarrhythmias and atrial fibrillation, are common in heart failure. A number of cardiac diseases including heart failure alter the expression and regulation of ion channels and transporters leading to arrhythmogenic electrical remodeling. Myocardial hypertrophy, fibrosis and scar formation are key elements of arrhythmogenic structural remodeling in heart failure. In this article, the mechanisms responsible for increased arrhythmia susceptibility as well as the underlying changes in ion channel, transporter expression and function as well as alterations in calcium handling in heart failure are discussed. Understanding the mechanisms of arrhythmogenic remodeling is key to improving arrhythmia management and the prevention of sudden cardiac death in patients with heart failure.
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Affiliation(s)
- Zoltán Husti
- Department of Pharmacology and Pharmacotherapy, University of Szeged, 6720 Szeged, Hungary; (Z.H.); (A.V.)
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, 6720 Szeged, Hungary
| | - András Varró
- Department of Pharmacology and Pharmacotherapy, University of Szeged, 6720 Szeged, Hungary; (Z.H.); (A.V.)
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, 6720 Szeged, Hungary
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research Network, 6720 Szeged, Hungary
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, University of Szeged, 6720 Szeged, Hungary; (Z.H.); (A.V.)
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, 6720 Szeged, Hungary
- Correspondence:
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5
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Stewart L, Turner NA. Channelling the Force to Reprogram the Matrix: Mechanosensitive Ion Channels in Cardiac Fibroblasts. Cells 2021; 10:990. [PMID: 33922466 PMCID: PMC8145896 DOI: 10.3390/cells10050990] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 04/13/2021] [Accepted: 04/21/2021] [Indexed: 02/06/2023] Open
Abstract
Cardiac fibroblasts (CF) play a pivotal role in preserving myocardial function and integrity of the heart tissue after injury, but also contribute to future susceptibility to heart failure. CF sense changes to the cardiac environment through chemical and mechanical cues that trigger changes in cellular function. In recent years, mechanosensitive ion channels have been implicated as key modulators of a range of CF functions that are important to fibrotic cardiac remodelling, including cell proliferation, myofibroblast differentiation, extracellular matrix turnover and paracrine signalling. To date, seven mechanosensitive ion channels are known to be functional in CF: the cation non-selective channels TRPC6, TRPM7, TRPV1, TRPV4 and Piezo1, and the potassium-selective channels TREK-1 and KATP. This review will outline current knowledge of these mechanosensitive ion channels in CF, discuss evidence of the mechanosensitivity of each channel, and detail the role that each channel plays in cardiac remodelling. By better understanding the role of mechanosensitive ion channels in CF, it is hoped that therapies may be developed for reducing pathological cardiac remodelling.
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Affiliation(s)
| | - Neil A. Turner
- Discovery and Translational Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds LS2 9JT, UK;
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Izzo C, Vitillo P, Di Pietro P, Visco V, Strianese A, Virtuoso N, Ciccarelli M, Galasso G, Carrizzo A, Vecchione C. The Role of Oxidative Stress in Cardiovascular Aging and Cardiovascular Diseases. Life (Basel) 2021; 11:60. [PMID: 33467601 PMCID: PMC7829951 DOI: 10.3390/life11010060] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/11/2021] [Accepted: 01/12/2021] [Indexed: 12/12/2022] Open
Abstract
Aging can be seen as process characterized by accumulation of oxidative stress induced damage. Oxidative stress derives from different endogenous and exogenous processes, all of which ultimately lead to progressive loss in tissue and organ structure and functions. The oxidative stress theory of aging expresses itself in age-related diseases. Aging is in fact a primary risk factor for many diseases and in particular for cardiovascular diseases and its derived morbidity and mortality. Here we highlight the role of oxidative stress in age-related cardiovascular aging and diseases. We take into consideration the molecular mechanisms, the structural and functional alterations, and the diseases accompanied to the cardiovascular aging process.
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Affiliation(s)
- Carmine Izzo
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Paolo Vitillo
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Paola Di Pietro
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Valeria Visco
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Andrea Strianese
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Nicola Virtuoso
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Michele Ciccarelli
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Gennaro Galasso
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
| | - Albino Carrizzo
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
- Department of Angio-Cardio-Neurology, Vascular Physiopathology Unit, IRCCS Neuromed, 86077 Pozzilli, Isernia, Italy
| | - Carmine Vecchione
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Baronissi, 84081 Salerno, Italy; (C.I.); (P.V.); (P.D.P.); (V.V.); (A.S.); (N.V.); (M.C.); (G.G.); (A.C.)
- Department of Angio-Cardio-Neurology, Vascular Physiopathology Unit, IRCCS Neuromed, 86077 Pozzilli, Isernia, Italy
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7
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Lu Y, Chen Y, Lin Y, Chen S, Chen Y. Mechanoelectrical feedback in pulmonary vein arrhythmogenesis: Clinical challenges and therapeutic opportunities. J Arrhythm 2020; 36:608-614. [PMID: 32782628 PMCID: PMC7411213 DOI: 10.1002/joa3.12391] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 05/28/2020] [Accepted: 06/04/2020] [Indexed: 12/24/2022] Open
Abstract
Mechanoelectrical feedback is an important factor in the pathophysiology of atrial fibrillation (AF). Ectopic electrical activity originating from pulmonary vein (PV) myocardial sleeves has been found to trigger and maintain paroxysmal AF. Dilated PVs by high stretching force may activate mechanoelectrical feedback, which induces calcium overload and produces afterdepolarization. These results, in turn, increase PV arrhythmogenesis and contribute to initiation of AF. Paracrine factors, effectors of the renin-angiotensin system, membranous channels, or cytoskeleton of PV myocytes may modulate PV arrhythmogenesis directly through mechanoelectrical feedback or indirectly through endocardial/myocardial cross-talk. The purpose of this review is to present laboratory and translational relevance of mechanoelectrical feedback in PV arrhythmogenesis. Targeting mechanoelectrical feedback in PV arrhythmogenesis may shed light on potential opportunities and clinical concerns of AF treatment.
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Affiliation(s)
- Yen‐Yu Lu
- Division of CardiologyDepartment of Internal MedicineSijhih Cathay General HospitalNew Taipei CityTaiwan
- School of MedicineFu‐Jen Catholic UniversityNew Taipei CityTaiwan
| | - Yao‐Chang Chen
- Department of Biomedical Engineering and Institute of PhysiologyNational Defense Medical CenterTaipeiTaiwan
| | - Yung‐Kuo Lin
- Division of Cardiovascular MedicineDepartment of Internal MedicineWan Fang HospitalTaipei Medical UniversityTaipeiTaiwan
- Cardiovacular Research CenterWan Fang HospitalTaipei Medical UniversityTaipeiTaiwan
| | - Shih‐Ann Chen
- Heart Rhythm Center and Division of CardiologyDepartment of MedicineTaipei Veterans General HospitalTaipeiTaiwan
| | - Yi‐Jen Chen
- Division of Cardiovascular MedicineDepartment of Internal MedicineWan Fang HospitalTaipei Medical UniversityTaipeiTaiwan
- Cardiovacular Research CenterWan Fang HospitalTaipei Medical UniversityTaipeiTaiwan
- Graduate Institute of Clinical MedicineCollege of MedicineTaipei Medical UniversityTaipeiTaiwan
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8
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Niestrawska JA, Augustin CM, Plank G. Computational modeling of cardiac growth and remodeling in pressure overloaded hearts-Linking microstructure to organ phenotype. Acta Biomater 2020; 106:34-53. [PMID: 32058078 PMCID: PMC7311197 DOI: 10.1016/j.actbio.2020.02.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 02/06/2020] [Accepted: 02/07/2020] [Indexed: 12/25/2022]
Abstract
Cardiac growth and remodeling (G&R) refers to structural changes in myocardial tissue in response to chronic alterations in loading conditions. One such condition is pressure overload where elevated wall stresses stimulate the growth in cardiomyocyte thickness, associated with a phenotype of concentric hypertrophy at the organ scale, and promote fibrosis. The initial hypertrophic response can be considered adaptive and beneficial by favoring myocyte survival, but over time if pressure overload conditions persist, maladaptive mechanisms favoring cell death and fibrosis start to dominate, ultimately mediating the transition towards an overt heart failure phenotype. The underlying mechanisms linking biological factors at the myocyte level to biomechanical factors at the systemic and organ level remain poorly understood. Computational models of G&R show high promise as a unique framework for providing a quantitative link between myocardial stresses and strains at the organ scale to biological regulatory processes at the cellular level which govern the hypertrophic response. However, microstructurally motivated, rigorously validated computational models of G&R are still in their infancy. This article provides an overview of the current state-of-the-art of computational models to study cardiac G&R. The microstructure and mechanosensing/mechanotransduction within cells of the myocardium is discussed and quantitative data from previous experimental and clinical studies is summarized. We conclude with a discussion of major challenges and possible directions of future research that can advance the current state of cardiac G&R computational modeling. STATEMENT OF SIGNIFICANCE: The mechanistic links between organ-scale biomechanics and biological factors at the cellular size scale remain poorly understood as these are largely elusive to investigations using experimental methodology alone. Computational G&R models show high promise to establish quantitative links which allow more mechanistic insight into adaptation mechanisms and may be used as a tool for stratifying the state and predict the progression of disease in the clinic. This review provides a comprehensive overview of research in this domain including a summary of experimental data. Thus, this study may serve as a basis for the further development of more advanced G&R models which are suitable for making clinical predictions on disease progression or for testing hypotheses on pathogenic mechanisms using in-silico models.
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Affiliation(s)
- Justyna A Niestrawska
- Gottfried Schatz Research Center: Division of Biophysics, Medical University of Graz, Graz 8010, Austria
| | - Christoph M Augustin
- Gottfried Schatz Research Center: Division of Biophysics, Medical University of Graz, Graz 8010, Austria.
| | - Gernot Plank
- Gottfried Schatz Research Center: Division of Biophysics, Medical University of Graz, Graz 8010, Austria; BioTechMed-Graz, Austria
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Zhan H, Zhang J, Jiao A, Wang Q. Stretch-activated current in human atrial myocytes and Na + current and mechano-gated channels' current in myofibroblasts alter myocyte mechanical behavior: a computational study. Biomed Eng Online 2019; 18:104. [PMID: 31653259 PMCID: PMC6814973 DOI: 10.1186/s12938-019-0723-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 10/16/2019] [Indexed: 12/19/2022] Open
Abstract
Background The activation of stretch-activated channels (SACs) in cardiac myocytes, which changes the phases of action potential repolarization, is proven to be highly efficient for the conversion of atrial fibrillation. The expression of Na+ current in myofibroblasts (Mfbs) regenerates myocytes’ action potentials, suggesting that Mfbs play an active role in triggering cardiac rhythm disturbances. Moreover, the excitation of mechano-gated channels (MGCs) in Mfbs depolarizes their membrane potential and contributes to the increased risk of post-infarct arrhythmia. Although these electrophysiological mechanisms have been largely known, the roles of these currents in cardiac mechanics are still debated. In this study, we aimed to investigate the mechanical influence of these currents via mathematical modeling. A novel mathematical model was developed by integrating models of human atrial myocyte (including the stretch-activated current, Ca2+–force relation, and mechanical behavior of a single segment) and Mfb (including our formulation of Na+ current and mechano-gated channels’ current). The effects of the changes in basic cycle length, number of coupled Mfbs and intercellular coupling conductance on myocyte mechanical properties were compared. Results Our results indicated that these three currents significantly regulated myocyte mechanical parameters. In isosarcometric contraction, these currents increased segment force by 13.8–36.6% and dropped element length by 12.1–31.5%. In isotonic contraction, there are 2.7–5.9% growth and 0.9–24% reduction. Effects of these currents on the extremum of myocyte mechanical parameters become more significant with the increase of basic cycle length, number of coupled Mfbs and intercellular coupling conductance. Conclusions The results demonstrated that stretch-activated current in myocytes and Na+ current and mechano-gated channels’ current in Mfbs significantly influenced myocyte mechanical behavior and should be considered in future cardiac mechanical mathematical modeling.
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Affiliation(s)
- Heqing Zhan
- College of Medical Information, Hainan Medical University, Haikou, 571199, China.
| | - Jingtao Zhang
- Cardiac Arrhythmia Center, Fuwai Hospital, National Center for Cardiovascular Diseases, Beijing, 100037, China
| | - Anquan Jiao
- College of Medical Information, Hainan Medical University, Haikou, 571199, China
| | - Qin Wang
- College of Medical Information, Hainan Medical University, Haikou, 571199, China
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10
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Chan CS, Lin YK, Chen YC, Lu YY, Chen SA, Chen YJ. Heart Failure Differentially Modulates Natural (Sinoatrial Node) and Ectopic (Pulmonary Veins) Pacemakers: Mechanism and Therapeutic Implication for Atrial Fibrillation. Int J Mol Sci 2019; 20:ijms20133224. [PMID: 31262061 PMCID: PMC6651382 DOI: 10.3390/ijms20133224] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 06/28/2019] [Accepted: 06/28/2019] [Indexed: 12/14/2022] Open
Abstract
Heart failure (HF) frequently coexists with atrial fibrillation (AF) and dysfunction of the sinoatrial node (SAN), the natural pacemaker. HF is associated with chronic adrenergic stimulation, neurohormonal activation, abnormal intracellular calcium handling, elevated cardiac filling pressure and atrial stretch, and fibrosis. Pulmonary veins (PVs), which are the points of onset of ectopic electrical activity, are the most crucial AF triggers. A crosstalk between the SAN and PVs determines PV arrhythmogenesis. HF has different effects on SAN and PV electrophysiological characteristics, which critically modulate the development of AF and sick sinus syndrome. This review provides updates to improve our current understanding of the effects of HF in the electrical activity of the SAN and PVs as well as therapeutic implications for AF.
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Affiliation(s)
- Chao-Shun Chan
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 11042, Taiwan
- Division of Cardiology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei 11042, Taiwan
| | - Yung-Kuo Lin
- Division of Cardiology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei 11042, Taiwan
- Division of Cardiovascular Medicine, Department of Internal Medicine, Wan-Fang Hospital, Taipei Medical University, Taipei 11696, Taiwan
| | - Yao-Chang Chen
- Department of Biomedical Engineering, National Defense Medical Center, Taipei 11490, Taiwan
| | - Yen-Yu Lu
- Division of Cardiology, Department of Internal Medicine, Sijhih Cathay General Hospital, New Taipei City 22174, Taiwan
- School of Medicine, College of Medicine, Fu-Jen Catholic University, New Taipei City 24257, Taiwan
| | - Shih-Ann Chen
- Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei 11217, Taiwan
- Institute of Clinical Medicine, and Cardiovascular Research Center, National Yang-Ming University, Taipei 11221, Taiwan
| | - Yi-Jen Chen
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 11042, Taiwan.
- Division of Cardiovascular Medicine, Department of Internal Medicine, Wan-Fang Hospital, Taipei Medical University, Taipei 11696, Taiwan.
- Cardiovascular Research Center, Wan-Fang Hospital, Taipei Medical University, Taipei 11696, Taiwan.
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11
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Saucerman JJ, Tan PM, Buchholz KS, McCulloch AD, Omens JH. Mechanical regulation of gene expression in cardiac myocytes and fibroblasts. Nat Rev Cardiol 2019; 16:361-378. [PMID: 30683889 PMCID: PMC6525041 DOI: 10.1038/s41569-019-0155-8] [Citation(s) in RCA: 110] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The intact heart undergoes complex and multiscale remodelling processes in response to altered mechanical cues. Remodelling of the myocardium is regulated by a combination of myocyte and non-myocyte responses to mechanosensitive pathways, which can alter gene expression and therefore function in these cells. Cellular mechanotransduction and its downstream effects on gene expression are initially compensatory mechanisms during adaptations to the altered mechanical environment, but under prolonged and abnormal loading conditions, they can become maladaptive, leading to impaired function and cardiac pathologies. In this Review, we summarize mechanoregulated pathways in cardiac myocytes and fibroblasts that lead to altered gene expression and cell remodelling under physiological and pathophysiological conditions. Developments in systems modelling of the networks that regulate gene expression in response to mechanical stimuli should improve integrative understanding of their roles in vivo and help to discover new combinations of drugs and device therapies targeting mechanosignalling in heart disease.
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Affiliation(s)
- Jeffrey J Saucerman
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Philip M Tan
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Kyle S Buchholz
- Departments of Bioengineering and Medicine, University of California San Diego, La Jolla, CA, USA
| | - Andrew D McCulloch
- Departments of Bioengineering and Medicine, University of California San Diego, La Jolla, CA, USA.
| | - Jeffrey H Omens
- Departments of Bioengineering and Medicine, University of California San Diego, La Jolla, CA, USA
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Yu C, Zhu W, Sun B, Mei D, Gou M, Chen S. Modulating physical, chemical, and biological properties in 3D printing for tissue engineering applications. APPLIED PHYSICS REVIEWS 2018; 5:041107. [PMID: 31938080 PMCID: PMC6959479 DOI: 10.1063/1.5050245] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Accepted: 09/17/2018] [Indexed: 02/05/2023]
Abstract
Over the years, 3D printing technologies have transformed the field of tissue engineering and regenerative medicine by providing a tool that enables unprecedented flexibility, speed, control, and precision over conventional manufacturing methods. As a result, there has been a growing body of research focused on the development of complex biomimetic tissues and organs produced via 3D printing to serve in various applications ranging from models for drug development to translational research and biological studies. With the eventual goal to produce functional tissues, an important feature in 3D printing is the ability to tune and modulate the microenvironment to better mimic in vivo conditions to improve tissue maturation and performance. This paper reviews various strategies and techniques employed in 3D printing from the perspective of achieving control over physical, chemical, and biological properties to provide a conducive microenvironment for the development of physiologically relevant tissues. We will also highlight the current limitations associated with attaining each of these properties in addition to introducing challenges that need to be addressed for advancing future 3D printing approaches.
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Affiliation(s)
- Claire Yu
- Department of NanoEngineering, University of California San
Diego, 9500 Gilman Drive, La Jolla, California 92093,
USA
| | - Wei Zhu
- Department of NanoEngineering, University of California San
Diego, 9500 Gilman Drive, La Jolla, California 92093,
USA
| | - Bingjie Sun
- Department of NanoEngineering, University of California San
Diego, 9500 Gilman Drive, La Jolla, California 92093,
USA
| | - Deqing Mei
- Department of Mechanical Engineering, Zhejiang
University, Hangzhou 310027, China
| | - Maling Gou
- State Key Laboratory of Biotherapy and Cancer Center, West
China Hospital, Sichuan University and Collaborative Innovation Center of
Biotherapy, Chengdu, People's Republic of China
| | - Shaochen Chen
- Department of NanoEngineering, University of California San
Diego, 9500 Gilman Drive, La Jolla, California 92093,
USA
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13
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Laredo M, Waldmann V, Khairy P, Nattel S. Age as a Critical Determinant of Atrial Fibrillation: A Two-sided Relationship. Can J Cardiol 2018; 34:1396-1406. [PMID: 30404745 DOI: 10.1016/j.cjca.2018.08.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 07/23/2018] [Accepted: 08/01/2018] [Indexed: 12/19/2022] Open
Abstract
The incidence of atrial fibrillation (AF), the most common sustained arrhythmia and a major public health burden, increases exponentially with age. However, mechanisms underlying this long-recognized association remain incompletely understood. Experimental and human studies have demonstrated the involvement of aging in several arrhythmogenic processes, including atrial electrical and structural remodelling, disturbed calcium homeostasis, and enhanced atrial ectopic activity/increased vulnerability to re-entry induction. Given this wide range of putative mechanisms, the task of delineating the specific effects of aging responsible for AF promotion is not simple, as aging is itself associated with increasing prevalence of a host of AF-predisposing conditions, including heart failure, coronary artery disease, and hypertension. Although we usually think of old age promoting AF, there is also evidence that young age may actually have a protective effect against AF occurrence. For example, the low AF incidence among populations of young patients with significant structural congenital heart disease and substantial atrial enlargement/remodelling suggests that younger age might protect against fibrillation in the diseased atrium; efforts at understating how younger age may prevent AF might be helpful in elucidating missing mechanistic links between AF and age. The goal of this paper is to review the epidemiologic and pathophysiologic evidence regarding mechanisms underlying age-related AF. Although the therapeutic options for AF have recently improved, major gaps still remain and a better understanding of the special relationship between age and AF may be important for the identification of new targets for therapeutic innovation.
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Affiliation(s)
- Mikael Laredo
- Montreal Heart Institute, Université de Montréal, Montreal, Québec, Canada; AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Institut de Cardiologie, Paris, France
| | - Victor Waldmann
- Montreal Heart Institute, Université de Montréal, Montreal, Québec, Canada
| | - Paul Khairy
- Montreal Heart Institute, Université de Montréal, Montreal, Québec, Canada.
| | - Stanley Nattel
- Montreal Heart Institute, Université de Montréal, Montreal, Québec, Canada; Department of Pharmacology and Therapeutics, McGill University, Montreal, Québec, Canada; Institute of Pharmacology, University Duisburg-Essen, Essen, Germany; LIRYC Center, Bordeaux, France.
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14
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Sachs F. Mechanical Transduction and the Dark Energy of Biology. Biophys J 2018; 114:3-9. [PMID: 29320693 PMCID: PMC5984904 DOI: 10.1016/j.bpj.2017.10.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 09/26/2017] [Accepted: 10/11/2017] [Indexed: 12/27/2022] Open
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15
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Lin YK, Chen YA, Lee TI, Chen YC, Chen SA, Chen YJ. Aging Modulates the Substrate and Triggers Remodeling in Atrial Fibrillation. Circ J 2017; 82:1237-1244. [PMID: 28904308 DOI: 10.1253/circj.cj-17-0242] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Aging plays a critical role in the genesis of atrial fibrillation (AF) and also increases the risks of cardiac dysfunction and stroke in AF patients. AF is caused by increased AF triggering from abnormalities of the thoracic vein and/or modulated substrate (atrial) with enhancement of AF maintenance. Clinical and laboratory evidence indicates that aging is significant in the creation of atrial electrical and structural remodeling that leads to increased susceptibility to AF occurrence. Aging is commonly associated with cardiovascular comorbidities, oxidative stress, calcium dysregulation, atrial myopathy with apoptosis, and fibrosis, which all contribute to the genesis of AF. This review updates the current understanding of the effects of aging on the pathophysiology of AF.
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Affiliation(s)
- Yung-Kuo Lin
- Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University.,Division of Cardiology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University
| | - Yi-Ann Chen
- Division of Nephrology, Sijhih Cathay General Hospital
| | - Ting-I Lee
- Division of Endocrinology and Metabolism, Wan Fang Hospital, Taipei Medical University
| | - Yao-Chang Chen
- Department of Biomedical Engineering, National Defense Medical Center
| | - Shih-Ann Chen
- Division of Cardiology and Cardiovascular Research Center, Veterans General Hospital-Taipei
| | - Yi-Jen Chen
- Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University.,Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University
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16
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Abstract
PURPOSE OF REVIEW The purpose of this review is to provide a broad overview of current trends in stem cell research and its applications in cardiovascular medicine. Researches on different stem cell sources, their inherent characteristics, and the limitations they have in medical applications are discussed. Additionally, uses of stem cells for both modeling and treating cardiovascular disease are discussed, taking note of the obstacles these engineered interventions must overcome to be clinically viable. RECENT FINDINGS Tissue engineering aims to replace dysfunctional tissues with engineered constructs. Stem cell technologies have been a great enabling factor in working toward this goal. Many tissue-engineered products are in development that utilize stem cell technology. Although promising, some refinement must be made to these constructs with respect to safety and functionality. A deeper understanding of basic differentiation and tissue developmental mechanisms is required to allow these engineered tissues to be translated into the clinic.
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Affiliation(s)
- Christopher W Anderson
- Vascular Biology and Therapeutics Program, Yale University, New Haven, CT, 06510, USA
- Molecular Cell Genetics and Developmental Biology Program, Yale University, New Haven, CT, 06510, USA
| | - Nicole Boardman
- Vascular Biology and Therapeutics Program, Yale University, New Haven, CT, 06510, USA
- Department of Internal Medicine, Section of Cardiovascular Medicine, Yale Cardiovascular Research Center, Yale School of Medicine, 300 George Street, Ste 773A, New Haven, CT, 06511, USA
| | - Jiesi Luo
- Vascular Biology and Therapeutics Program, Yale University, New Haven, CT, 06510, USA
- Department of Internal Medicine, Section of Cardiovascular Medicine, Yale Cardiovascular Research Center, Yale School of Medicine, 300 George Street, Ste 773A, New Haven, CT, 06511, USA
| | - Jinkyu Park
- Vascular Biology and Therapeutics Program, Yale University, New Haven, CT, 06510, USA
- Department of Internal Medicine, Section of Cardiovascular Medicine, Yale Cardiovascular Research Center, Yale School of Medicine, 300 George Street, Ste 773A, New Haven, CT, 06511, USA
| | - Yibing Qyang
- Vascular Biology and Therapeutics Program, Yale University, New Haven, CT, 06510, USA.
- Department of Internal Medicine, Section of Cardiovascular Medicine, Yale Cardiovascular Research Center, Yale School of Medicine, 300 George Street, Ste 773A, New Haven, CT, 06511, USA.
- Yale Stem Cell Center, Yale University, New Haven, CT, 06510, USA.
- Department of Pathology, Yale University, New Haven, CT, 06510, USA.
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Sridhar S, Vandersickel N, Panfilov AV. Effect of myocyte-fibroblast coupling on the onset of pathological dynamics in a model of ventricular tissue. Sci Rep 2017; 7:40985. [PMID: 28106124 PMCID: PMC5247688 DOI: 10.1038/srep40985] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 12/13/2016] [Indexed: 12/23/2022] Open
Abstract
Managing lethal cardiac arrhythmias is one of the biggest challenges in modern cardiology, and hence it is very important to understand the factors underlying such arrhythmias. While early afterdepolarizations (EAD) of cardiac cells is known to be one such arrhythmogenic factor, the mechanisms underlying the emergence of tissue level arrhythmias from cellular level EADs is not fully understood. Another known arrhythmogenic condition is fibrosis of cardiac tissue that occurs both due to aging and in many types of heart diseases. In this paper we describe the results of a systematic in-silico study, using the TNNP model of human cardiac cells and MacCannell model for (myo)fibroblasts, on the possible effects of diffuse fibrosis on arrhythmias occurring via EADs. We find that depending on the resting potential of fibroblasts (VFR), M-F coupling can either increase or decrease the region of parameters showing EADs. Fibrosis increases the probability of occurrence of arrhythmias after a single focal stimulation and this effect increases with the strength of the M-F coupling. While in our simulations, arrhythmias occur due to fibrosis induced ectopic activity, we do not observe any specific fibrotic pattern that promotes the occurrence of these ectopic sources.
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Affiliation(s)
- S. Sridhar
- Department of Physics and Astronomy, Ghent University, Ghent, Belgium
| | - Nele Vandersickel
- Department of Physics and Astronomy, Ghent University, Ghent, Belgium
| | - Alexander V. Panfilov
- Department of Physics and Astronomy, Ghent University, Ghent, Belgium
- Moscow Institute of Physics and Technology (State University), Dolgoprudny, Moscow Region, Russia
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18
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Effects of Na + Current and Mechanogated Channels in Myofibroblasts on Myocyte Excitability and Repolarization. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2016; 2016:6189374. [PMID: 27980607 PMCID: PMC5131562 DOI: 10.1155/2016/6189374] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 10/09/2016] [Accepted: 10/19/2016] [Indexed: 12/19/2022]
Abstract
Fibrotic remodeling, characterized by fibroblast phenotype switching, is often associated with atrial fibrillation and heart failure. This study aimed to investigate the effects on electrotonic myofibroblast-myocyte (Mfb-M) coupling on cardiac myocytes excitability and repolarization of the voltage-gated sodium channels (VGSCs) and single mechanogated channels (MGCs) in human atrial Mfbs. Mathematical modeling was developed from a combination of (1) models of the human atrial myocyte (including the stretch activated ion channel current, ISAC) and Mfb and (2) our formulation of currents through VGSCs (INa_Mfb) and MGCs (IMGC_Mfb) based upon experimental findings. The effects of changes in the intercellular coupling conductance, the number of coupled Mfbs, and the basic cycle length on the myocyte action potential were simulated. The results demonstrated that the integration of ISAC, INa_Mfb, and IMGC_Mfb reduced the amplitude of the myocyte membrane potential (Vmax) and the action potential duration (APD), increased the depolarization of the resting myocyte membrane potential (Vrest), and made it easy to trigger spontaneous excitement in myocytes. For Mfbs, significant electrotonic depolarizations were exhibited with the addition of INa_Mfb and IMGC_Mfb. Our results indicated that ISAC, INa_Mfb, and IMGC_Mfb significantly influenced myocytes and Mfbs properties and should be considered in future cardiac pathological mathematical modeling.
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19
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Chiang MY, Hsu YW, Hsieh HY, Chen SY, Fan SK. Constructing 3D heterogeneous hydrogels from electrically manipulated prepolymer droplets and crosslinked microgels. SCIENCE ADVANCES 2016; 2:e1600964. [PMID: 27819046 PMCID: PMC5091359 DOI: 10.1126/sciadv.1600964] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 09/26/2016] [Indexed: 05/13/2023]
Abstract
Formation of multifunctional, heterogeneous, and encoded hydrogel building blocks, or microgels, by crosslinking and assembly of microgels are two essential steps in establishing hierarchical, complicated, and three-dimensional (3D) hydrogel architectures that recapitulate natural and biological structures or originate new materials by design. However, for the variety of the hydrogel materials crosslinked differently and for the varied scales of microgels and architectures, the formation and assembly processes are usually performed separately, which increases the manufacturing complexity of designed hydrogel materials. We show the construction of hydrogel architectures through programmable formation and assembly on an electromicrofluidic platform, adopting two reciprocal electric manipulations (electrowetting and dielectrophoresis) to manipulate varied objects (i) in multiple phases, including prepolymer liquid droplets and crosslinked microgels, (ii) on a wide range of scales from micrometer functional particles or cells to millimeter-assembled hydrogel architectures, and (iii) with diverse properties, such as conductive and dielectric droplets that are photocrosslinkable, chemically crosslinkable, or thermally crosslinkable. Prepolymer droplets, particles, and dissolved molecules are electrically addressable to adjust the properties of the microgel building blocks in liquid phase that subsequently undergo crosslinking and assembly in a flexible sequence to accomplish heterogeneous and seamless hydrogel architectures. We expect the electromicrofluidic platform to become a general technique to obtain 3D complex architectures.
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Affiliation(s)
- Min-Yu Chiang
- Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu, Taiwan
| | - Yao-Wen Hsu
- Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu, Taiwan
| | - Hsin-Yi Hsieh
- Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan
| | - San-Yuan Chen
- Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu, Taiwan
| | - Shih-Kang Fan
- Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan
- Center of Biotechnology, National Taiwan University, Taipei, Taiwan
- Corresponding author.
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20
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Left ventricular longitudinal systolic dysfunction is associated with right atrial dyssynchrony in heart failure with preserved ejection fraction. REVISTA PORTUGUESA DE CARDIOLOGIA (ENGLISH EDITION) 2016. [DOI: 10.1016/j.repce.2015.11.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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21
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Bytyçi I, Haliti E, Berisha G, Tishukaj A, Shatri F, Bajraktari G. Left ventricular longitudinal systolic dysfunction is associated with right atrial dyssynchrony in heart failure with preserved ejection fraction. Rev Port Cardiol 2016; 35:207-14. [PMID: 26992745 DOI: 10.1016/j.repc.2015.11.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2015] [Accepted: 11/21/2015] [Indexed: 02/08/2023] Open
Abstract
OBJECTIVE We aimed in this study to assess the role of longitudinal left ventricular (LV) systolic function in heart failure with preserved ejection fraction (HFpEF) in delayed intra- and interatrial conduction time. METHODS In 85 consecutive patients with HFpEF (age 60±11 years, ejection fraction [EF] ≥45%), a complete M-mode echocardiographic and tissue Doppler imaging (TDI) study was performed. The times from the onset of the P wave on the ECG to the beginning of the A' wave (PA) from the lateral and septal mitral and tricuspid annuli on TDI were recorded. The difference between these intervals gave the intra- and interatrial dyssynchrony. Based on mitral annular plane systolic excursion (MAPSE), patients were classified as having HFpEF with impaired (MAPSE ≤1.2 cm) or normal (MAPSE >1.2 cm) longitudinal systolic function. RESULTS Patients with impaired MAPSE were older (p<0.001), had higher LV mass index (p<0.001), greater left atrial (LA) minimum volume (p=0.007), reduced left atrial EF (p<0.001), higher E/e' ratio (p=0.002), reduced lateral and septal e' wave (p=0.005 and p=0.006, respectively), prolonged tricuspid PA' (p=0.03) and significantly increased right atrial (RA) dyssynchrony (p=0.001) compared with normal MAPSE. MAPSE correlated with RA dyssynchrony (r=-0.40, p<0.001) but not with interatrial and LA dyssynchrony. CONCLUSION In patients with HFpEF and impaired MAPSE, RA dyssynchrony is increased, compared to those with normal MAPSE. As patients with RA dyssynchrony are at higher risk for arrhythmia, assessment of this dyssynchrony may help to improve treatment, as well as to predict outcome in these patients.
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Affiliation(s)
- Ibadete Bytyçi
- Clinic of Cardiology, University Clinical Centre of Kosova, Prishtina, Kosovo.
| | - Edmond Haliti
- Clinic of Cardiology, University Clinical Centre of Kosova, Prishtina, Kosovo
| | - Gëzim Berisha
- Clinic of Cardiology, University Clinical Centre of Kosova, Prishtina, Kosovo
| | - Arbërie Tishukaj
- Clinic of Cardiology, University Clinical Centre of Kosova, Prishtina, Kosovo
| | - Faik Shatri
- Clinic of Cardiology, University Clinical Centre of Kosova, Prishtina, Kosovo
| | - Gani Bajraktari
- Clinic of Cardiology, University Clinical Centre of Kosova, Prishtina, Kosovo
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22
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Pellman J, Zhang J, Sheikh F. Myocyte-fibroblast communication in cardiac fibrosis and arrhythmias: Mechanisms and model systems. J Mol Cell Cardiol 2016; 94:22-31. [PMID: 26996756 DOI: 10.1016/j.yjmcc.2016.03.005] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 02/27/2016] [Accepted: 03/14/2016] [Indexed: 12/17/2022]
Abstract
Development of cardiac fibrosis and arrhythmias is controlled by the activity of and communication between cardiomyocytes and fibroblasts in the heart. Myocyte-fibroblast interactions occur via both direct and indirect means including paracrine mediators, extracellular matrix interactions, electrical modulators, mechanical junctions, and membrane nanotubes. In the diseased heart, cardiomyocyte and fibroblast ratios and activity, and thus myocyte-fibroblast interactions, change and are thought to contribute to the course of disease including development of fibrosis and arrhythmogenic activity. Fibroblasts have a developing role in modulating cardiomyocyte electrical and hypertrophic activity, however gaps in knowledge regarding these interactions still exist. Research in this field has necessitated the development of unique approaches to isolate and control myocyte-fibroblast interactions. Numerous methods for 2D and 3D co-culture systems have been developed, while a growing part of this field is in the use of better tools for in vivo systems including cardiomyocyte and fibroblast specific Cre mouse lines for cell type specific genetic ablation. This review will focus on (i) mechanisms of myocyte-fibroblast communication and their effects on disease features such as cardiac fibrosis and arrhythmias as well as (ii) methods being used and currently developed in this field.
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Affiliation(s)
- Jason Pellman
- Department of Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Jing Zhang
- Department of Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Farah Sheikh
- Department of Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.
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23
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Extracellular matrix-mediated cellular communication in the heart. J Mol Cell Cardiol 2016; 91:228-37. [PMID: 26778458 DOI: 10.1016/j.yjmcc.2016.01.011] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 01/10/2016] [Accepted: 01/11/2016] [Indexed: 01/13/2023]
Abstract
The extracellular matrix (ECM) is a complex and dynamic scaffold that maintains tissue structure and dynamics. However, the view of the ECM as an inert architectural support has been increasingly challenged. The ECM is a vibrant meshwork, a crucial organizer of cellular microenvironments. It plays a direct role in cellular interactions regulating cell growth, survival, spreading, proliferation, differentiation and migration through the intricate relationship among cellular and acellular tissue components. This complex interrelationship preserves cardiac function during homeostasis; however it is also responsible for pathologic remodeling following myocardial injury. Therefore, enhancing our understanding of this cross-talk may provide mechanistic insights into the pathogenesis of heart failure and suggest new approaches to novel, targeted pharmacologic therapies. This review explores the implications of ECM-cell interactions in myocardial cell behavior and cardiac function at baseline and following myocardial injury.
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24
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Ongstad E, Kohl P. Fibroblast-myocyte coupling in the heart: Potential relevance for therapeutic interventions. J Mol Cell Cardiol 2016; 91:238-46. [PMID: 26774702 DOI: 10.1016/j.yjmcc.2016.01.010] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 01/09/2016] [Accepted: 01/11/2016] [Indexed: 01/03/2023]
Abstract
Cardiac myocyte-fibroblast electrotonic coupling is a well-established fact in vitro. Indirect evidence of its presence in vivo exists, but few functional studies have been published. This review describes the current knowledge of fibroblast-myocyte electrical signaling in the heart. Further research is needed to understand the frequency and extent of heterocellular interactions in vivo in order to gain a better understanding of their relevance in healthy and diseased myocardium. It is hoped that associated insight into myocyte-fibroblast coupling in the heart may lead to the discovery of novel therapeutic targets and the development of agents for improving outcomes of myocardial scarring and fibrosis.
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Affiliation(s)
- Emily Ongstad
- Clemson University, Department of Bioengineering, Clemson, SC, USA; Virginia Tech Carilion Research Institute, Roanoke, VA, USA.
| | - Peter Kohl
- Institute for Experimental Cardiovascular Medicine, University Heart Centre Freiburg - Bad Krozingen, Faculty of Medicine, University Freiburg, Germany; Cardiac Biophysics and Systems Biology, National Heart and Lung Institute, Imperial College London, UK
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25
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Tolstokorov AS, Syunyaev RA, Aliev RR. Simulation of the fibroblast effect on electrical activity of sinoatrial node cells. Biophysics (Nagoya-shi) 2015. [DOI: 10.1134/s0006350915020190] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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26
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Fleischman A, Vecchio C, Sunny Y, Bawiec CR, Lewin PA, Kresh JY, Kohut AR. Ultrasound-induced modulation of cardiac rhythm in neonatal rat ventricular cardiomyocytes. J Appl Physiol (1985) 2015; 118:1423-8. [PMID: 25858493 DOI: 10.1152/japplphysiol.00980.2014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 04/02/2015] [Indexed: 11/22/2022] Open
Abstract
Isolated neonatal rat ventricular cardiomyocytes were used to study the influence of ultrasound on the chronotropic response in a tissue culture model. The beat frequency of the cells, varying from 40 to 90 beats/min, was measured based upon the translocation of the nuclear membrane captured by a high-speed camera. Ultrasound pulses (frequency = 2.5 MHz) were delivered at 300-ms intervals [3.33 Hz pulse repetition frequency (PRF)], in turn corresponding to 200 pulses/min. The intensity of acoustic energy and pulse duration were made variable, 0.02-0.87 W/cm(2) and 1-5 ms, respectively. In 57 of 99 trials, there was a noted average increase in beat frequency of 25% with 8-s exposures to ultrasonic pulses. Applied ultrasound energy with a spatial peak time average acoustic intensity (Ispta) of 0.02 W/cm(2) and pulse duration of 1 ms effectively increased the contraction rate of cardiomyocytes (P < 0.05). Of the acoustic power tested, the lowest level of acoustic intensity and shortest pulse duration proved most effective at increasing the electrophysiological responsiveness and beat frequency of cardiomyocytes. Determining the optimal conditions for delivery of ultrasound will be essential to developing new models for understanding mechanoelectrical coupling (MEC) and understanding novel nonelectrical pacing modalities for clinical applications.
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Affiliation(s)
| | - Christopher Vecchio
- School of Biomedical Engineering, Science & Health System, Drexel University, Philadelphia, Pennsylvania; and
| | - Youhan Sunny
- School of Biomedical Engineering, Science & Health System, Drexel University, Philadelphia, Pennsylvania; and
| | - Christopher R Bawiec
- School of Biomedical Engineering, Science & Health System, Drexel University, Philadelphia, Pennsylvania; and
| | - Peter A Lewin
- School of Biomedical Engineering, Science & Health System, Drexel University, Philadelphia, Pennsylvania; and
| | - J Yasha Kresh
- Department of Medicine, School of Medicine and School of Biomedical Engineering, Science & Health System, Drexel University, Philadelphia, Pennsylvania; and Department of Cardiothoracic Surgery, School of Medicine School of Medicine and Drexel University, Philadelphia, Pennsylvania
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27
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Dostal D, Glaser S, Baudino TA. Cardiac Fibroblast Physiology and Pathology. Compr Physiol 2015; 5:887-909. [DOI: 10.1002/cphy.c140053] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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28
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Lu TY, Lin B, Kim J, Sullivan M, Tobita K, Salama G, Yang L. Repopulation of decellularized mouse heart with human induced pluripotent stem cell-derived cardiovascular progenitor cells. Nat Commun 2014; 4:2307. [PMID: 23942048 DOI: 10.1038/ncomms3307] [Citation(s) in RCA: 253] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 07/15/2013] [Indexed: 01/15/2023] Open
Abstract
Heart disease is the leading cause of death in the world. Heart tissue engineering holds a great promise for future heart disease therapy by building personalized heart tissues. Here we create heart constructs by repopulating decellularized mouse hearts with human induced pluripotent stem cell-derived multipotential cardiovascular progenitor cells. We show that the seeded multipotential cardiovascular progenitor cells migrate, proliferate and differentiate in situ into cardiomyocytes, smooth muscle cells and endothelial cells to reconstruct the decellularized hearts. After 20 days of perfusion, the engineered heart tissues exhibit spontaneous contractions, generate mechanical force and are responsive to drugs. In addition, we observe that heart extracellular matrix promoted cardiomyocyte proliferation, differentiation and myofilament formation from the repopulated human multipotential cardiovascular progenitor cells. Our novel strategy to engineer personalized heart constructs could benefit the study of early heart formation or may find application in preclinical testing.
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Affiliation(s)
- Tung-Ying Lu
- Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15201, USA
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29
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Wu CT, Qi XY, Huang H, Naud P, Dawson K, Yeh YH, Harada M, Kuo CT, Nattel S. Disease and region-related cardiac fibroblast potassium current variations and potential functional significance. Cardiovasc Res 2014; 102:487-96. [PMID: 24596399 DOI: 10.1093/cvr/cvu055] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
AIMS Fibroblasts, which play an important role in cardiac function/dysfunction, including arrhythmogenesis, have voltage-dependent (Kv) currents of unknown importance. Here, we assessed the differential expression of Kv currents between atrial and ventricular fibroblasts from control dogs and dogs with an atrial arrhythmogenic substrate caused by congestive heart failure (CHF). METHODS AND RESULTS Left atrial (LA) and ventricular (LV) fibroblasts were freshly isolated from control and CHF dogs (2-week ventricular tachypacing, 240 bpm). Kv currents were measured with whole-cell voltage-clamp, mRNA by quantitative polymerase chain reaction (qPCR) and fibroblast proliferation by (3)H-thymidine incorporation. Robust voltage-dependent tetraethylammonium (TEA)-sensitive K(+) currents (IC50 ∼1 mM) were recorded. The morphologies and TEA responses of LA and LV fibroblast Kv currents were similar. LV fibroblast Kv-current densities were significantly greater than LA, and Kv-current densities were significantly less in CHF than control. The mRNA expression of Kv-channel subunits Kv1.5 and Kv4.3 was less in LA vs. LV fibroblasts and was down-regulated in CHF, consistent with K(+)-current recordings. Ca(2+)-dependent K(+)-channel subunit (KCa1.1) mRNA and currents were less expressed in LV vs. LA fibroblasts. Inhibiting LA fibroblast K(+) current with 1 mmol/L of TEA or KCa1.1 current with paxilline increased proliferation. CONCLUSIONS Fibroblast Kv-current expression is smaller in CHF vs. control, as well as LA vs. LV. KCa1.1 current is greater in LA vs. LV. Suppressing Kv current with TEA enhances fibroblast proliferation, suggesting that Kv current might act to check fibroblast proliferation and that reduced Kv current in CHF may contribute to fibrosis. Fibroblast Kv-current remodelling may play a role in the atrial fibrillation (AF) substrate; modulating fibroblast K(+) channels may present a novel strategy to prevent fibrosis and AF.
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Affiliation(s)
- Chia-Tung Wu
- Research Center, Montreal Heart Institute, Université de Montréal, 5000 Belanger St. E., Montreal, QC, Canada H1T 1C8 Chang-Gung Memorial Hospital and University, Taoyuan, Taiwan, Republic of China
| | - Xiao-Yan Qi
- Research Center, Montreal Heart Institute, Université de Montréal, 5000 Belanger St. E., Montreal, QC, Canada H1T 1C8
| | - Hai Huang
- Research Center, Montreal Heart Institute, Université de Montréal, 5000 Belanger St. E., Montreal, QC, Canada H1T 1C8
| | - Patrice Naud
- Research Center, Montreal Heart Institute, Université de Montréal, 5000 Belanger St. E., Montreal, QC, Canada H1T 1C8
| | - Kristin Dawson
- Research Center, Montreal Heart Institute, Université de Montréal, 5000 Belanger St. E., Montreal, QC, Canada H1T 1C8 Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Yung-Hsin Yeh
- Chang-Gung Memorial Hospital and University, Taoyuan, Taiwan, Republic of China
| | - Masahide Harada
- Research Center, Montreal Heart Institute, Université de Montréal, 5000 Belanger St. E., Montreal, QC, Canada H1T 1C8 Department of Cardiology, Hamamatsu Medical Center, Hamamatsu, Japan
| | - Chi-Tai Kuo
- Chang-Gung Memorial Hospital and University, Taoyuan, Taiwan, Republic of China
| | - Stanley Nattel
- Research Center, Montreal Heart Institute, Université de Montréal, 5000 Belanger St. E., Montreal, QC, Canada H1T 1C8 Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
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Lin B, Lu TY, Yang L. Hear the beat: decellularized mouse heart regenerated with human induced pluripotent stem cells. Expert Rev Cardiovasc Ther 2014; 12:135-7. [DOI: 10.1586/14779072.2014.879039] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Abramochkin DV, Lozinsky IT, Kamkin A. Influence of mechanical stress on fibroblast-myocyte interactions in mammalian heart. J Mol Cell Cardiol 2014; 70:27-36. [PMID: 24389344 DOI: 10.1016/j.yjmcc.2013.12.020] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 12/18/2013] [Accepted: 12/24/2013] [Indexed: 12/18/2022]
Abstract
Cardiac fibroblasts are an essential component of cardiac tissue. These cells not only produce the extracellular matrix, but also are electrically and mechanically coupled with cardiomyocytes. In this way, fibroblasts can influence the electrical activity of cardiomyocytes. Cardiac fibroblasts cannot generate action potentials, but their membrane potential is controlled by mechanical stretch or compression of the surrounding myocardium which in turn affects their interaction with myocytes and the way myocytes respond to mechanical stress. This review discusses the electrical properties of cardiac fibroblasts, the present evidence of fibroblast-myocyte coupling and the way in which these cells respond to mechanical stress. This article is part of a Special Issue entitled "Myocyte-Fibroblast Signalling in Myocardium."
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Affiliation(s)
- Denis V Abramochkin
- Department of Fundamental and Applied Physiology, Russian National Research Medical University, Ostrovityanova str., 1, Moscow, Russia; Department of Human and Animal Physiology, Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia.
| | - Ilya T Lozinsky
- Department of Fundamental and Applied Physiology, Russian National Research Medical University, Ostrovityanova str., 1, Moscow, Russia
| | - Andre Kamkin
- Department of Fundamental and Applied Physiology, Russian National Research Medical University, Ostrovityanova str., 1, Moscow, Russia
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Howard CM, Baudino TA. Dynamic cell-cell and cell-ECM interactions in the heart. J Mol Cell Cardiol 2013; 70:19-26. [PMID: 24140801 DOI: 10.1016/j.yjmcc.2013.10.006] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Revised: 10/07/2013] [Accepted: 10/09/2013] [Indexed: 12/17/2022]
Abstract
Recent studies have placed an increasing amount of emphasis on the cardiovascular system and understanding how the heart and its vasculature can be regenerated following pathological stresses, such as hypertension and myocardial infarction. The remodeling process involves the permanent cellular constituents of the heart including myocytes, fibroblasts, endothelial cells, pericytes, smooth muscle cells and stem cells. It also includes transient cell populations, such as immune cells (e.g. lymphocytes, mast cells and macrophages) and circulating stem cells. Following injury, there are dramatic shifts in the various cardiac cell populations that can affect cell-cell and cell-extracellular matrix interactions and cardiac function. Cardiac fibroblasts are a key component in normal heart function, as well as during the remodeling process through dynamic cell-cell interactions and synthesis and degradation of the extracellular matrix. Fibroblasts dynamically interact with the various cardiac cell populations through mechanical, chemical (autocrine and/or paracrine) and electrophysiological means to alter gene and protein expression, cellular processes and ultimately cardiac function. Better understanding these cell-cell and cell-extracellular matrix interactions and their biological consequences should provide novel therapeutic targets for the treatment of heart disease. In this review we discuss the nature of these interactions and the importance of these interactions in maintaining normal heart function, as well as their role in the cardiac remodeling process. This article is part of a Special Issue entitled "Myocyte-Fibroblast Signalling in Myocardium."
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Affiliation(s)
| | - Troy A Baudino
- Department of Medicine, Division of Molecular Cardiology, Cardiovascular Research Institute, Texas A&M Health Science Center, Temple, TX 76504, USA; Central Texas Veterans Health Care System, Temple, TX 76504, USA.
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Deng DD, Gong YL, Shou GF, Jiao PF, Zhang HG, Ye XS, Xia L. Simulation of biatrial conduction via different pathways during sinus rhythm with a detailed human atrial model. J Zhejiang Univ Sci B 2013; 13:676-94. [PMID: 22949359 DOI: 10.1631/jzus.b1100339] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
In order to better understand biatrial conduction, investigate various conduction pathways, and compare the differences between isotropic and anisotropic conductions in human atria, we present a simulation study of biatrial conduction with known/assumed conduction pathways using a recently developed human atrial model. In addition to known pathways: (1) Bachmann's bundle (BB), (2) limbus of fossa ovalis (LFO), and (3) coronary sinus (CS), we also hypothesize that there exist two fast conduction bundles that connect the crista terminalis (CT), LFO, and CS. Our simulation demonstrates that use of these fast conduction bundles results in a conduction pattern consistent with experimental data. The comparison of isotropic and anisotropoic conductions in the BB case showed that the atrial working muscles had small effect on conduction time and conduction speed, although the conductivities assigned in anisotropic conduction were two to four times higher than the isotropic conduction. In conclusion, we suggest that the hypothesized intercaval bundles play a significant role in the biatrial conduction and that myofiber orientation has larger effects on the conduction system than the atrial working muscles. This study presents readers with new insights into human atrial conduction.
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Affiliation(s)
- Dong-dong Deng
- College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou 310027, China
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Wang L, Li H, Yang S. Role of oxygen free radicals in the proliferation of myofibroblasts induced by AngII. Acta Pharm Sin B 2013. [DOI: 10.1016/j.apsb.2012.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Shklyar TF, Dinislamova OA, Safronov AP, Blyakhman FA. Effect of cytoskeletal elastic properties on the mechanoelectrical transduction in excitable cells. J Biomech 2012; 45:1444-9. [DOI: 10.1016/j.jbiomech.2012.02.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Revised: 01/14/2012] [Accepted: 02/16/2012] [Indexed: 11/25/2022]
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Salameh A, Dhein S. Effects of mechanical forces and stretch on intercellular gap junction coupling. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2012; 1828:147-56. [PMID: 22245380 DOI: 10.1016/j.bbamem.2011.12.030] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Revised: 12/17/2011] [Accepted: 12/27/2011] [Indexed: 01/27/2023]
Abstract
Mechanical forces provide fundamental physiological stimulus in living organisms. Recent investigations demonstrated how various types of mechanical load, like strain, pressure, shear stress, or cyclic stretch can affect cell biology and gap junction intercellular communication (GJIC). Depending on the cell type, the type of mechanical load and on strength and duration of application, these forces can induce hypertrophic processes and modulate the expression and function of certain connexins such as Cx43, while others such as Cx37 or Cx40 are reported to be less mechanosensitive. In particular, not only expression but also subcellular localization of Cx43 is altered in cardiomyocytes submitted to cyclic mechanical stretch resulting in the typical elongated cell shape with an accentuation of Cx43 at the cell poles. In the heart both cardiomyocytes and fibroblasts can alter their GJIC in response to mechanical load. In the vasculature both endothelial cells and smooth muscle cells are subject to strain and cyclic stretch resulting from the pulsatile flow. In addition, vascular endothelial cells are mainly affected by shear stress resulting from the blood flow parallel to their surface. These mechanical forces lead to a regulation of GJIC in vascular tissue. In bones, osteocytes and osteoblasts are coupled via gap junctions, which also react to mechanical forces. Since gap junctions are involved in regulation of cell growth and differentiation, the mechanosensitivity of the regulation of these channels might open new perspectives to explain how cells can respond to mechanical load, and how stretch induces self-organization of a cell layer which might have implications for embryology and the development of organs. This article is part of a Special Issue entitled: The Communicating junctions, roles and dysfunctions.
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Affiliation(s)
- Aida Salameh
- Clinic for Pediatric Cardiology, University of Leipzig, Heart Centre, Germany
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Weise LD, Panfilov AV. New mechanism of spiral wave initiation in a reaction-diffusion-mechanics system. PLoS One 2011; 6:e27264. [PMID: 22114667 PMCID: PMC3215707 DOI: 10.1371/journal.pone.0027264] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2011] [Accepted: 10/12/2011] [Indexed: 11/21/2022] Open
Abstract
Spiral wave initiation in the heart muscle is a mechanism for the onset of dangerous cardiac arrhythmias. A standard protocol for spiral wave initiation is the application of a stimulus in the refractory tail of a propagating excitation wave, a region that we call the “classical vulnerable zone.” Previous studies of vulnerability to spiral wave initiation did not take the influence of deformation into account, which has been shown to have a substantial effect on the excitation process of cardiomyocytes via the mechano-electrical feedback phenomenon. In this work we study the effect of deformation on the vulnerability of excitable media in a discrete reaction-diffusion-mechanics (dRDM) model. The dRDM model combines FitzHugh-Nagumo type equations for cardiac excitation with a discrete mechanical description of a finite-elastic isotropic material (Seth material) to model cardiac excitation-contraction coupling and stretch activated depolarizing current. We show that deformation alters the “classical,” and forms a new vulnerable zone at longer coupling intervals. This mechanically caused vulnerable zone results in a new mechanism of spiral wave initiation, where unidirectional conduction block and rotation directions of the consequently initiated spiral waves are opposite compared to the mechanism of spiral wave initiation due to the “classical vulnerable zone.” We show that this new mechanism of spiral wave initiation can naturally occur in situations that involve wave fronts with curvature, and discuss its relation to supernormal excitability of cardiac tissue. The concept of mechanically induced vulnerability may lead to a better understanding about the onset of dangerous heart arrhythmias via mechano-electrical feedback.
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Affiliation(s)
- Louis D Weise
- Department of Theoretical Biology, Utrecht University, Utrecht, The Netherlands.
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Nguyen TP, Xie Y, Garfinkel A, Qu Z, Weiss JN. Arrhythmogenic consequences of myofibroblast-myocyte coupling. Cardiovasc Res 2011; 93:242-51. [PMID: 22049532 DOI: 10.1093/cvr/cvr292] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
AIMS Fibrosis is known to promote cardiac arrhythmias by disrupting myocardial structure. Given recent evidence that myofibroblasts form gap junctions with myocytes at least in co-cultures, we investigated whether myofibroblast-myocyte coupling can promote arrhythmia triggers, such as early afterdepolarizations (EADs), by directly influencing myocyte electrophysiology. METHODS AND RESULTS Using the dynamic voltage clamp technique, patch-clamped adult rabbit ventricular myocytes were electrotonically coupled to one or multiple virtual fibroblasts or myofibroblasts programmed with eight combinations of capacitance, membrane resistance, resting membrane potential, and gap junction coupling resistance, spanning physiologically realistic ranges. Myocytes were exposed to oxidative (1 mmol/L H(2)O(2)) or ionic (2.7 mmol/L hypokalaemia) stress to induce bradycardia-dependent EADs. In the absence of myofibroblast-myocyte coupling, EADs developed during slow pacing (6 s), but were completely suppressed by faster pacing (1 s). However, in the presence of myofibroblast-myocyte coupling, EADs could no longer be suppressed by rapid pacing, especially when myofibroblast resting membrane potential was depolarized (-25 mV). Analysis of the myofibroblast-myocyte virtual gap junction currents revealed two components: an early transient-outward I(to)-like current and a late sustained current. Selective elimination of the I(to)-like component prevented EADs, whereas selective elimination of the late component did not. CONCLUSION Coupling of myocytes to myofibroblasts promotes EAD formation as a result of a mismatch in early vs. late repolarization reserve caused by the I(to)-like component of the gap junction current. These cellular and ionic mechanisms may contribute to the pro-arrhythmic risk in fibrotic hearts.
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Affiliation(s)
- Thao P Nguyen
- UCLA Cardiovascular Research Laboratory, Division of Cardiology, Department of Medicine, Los Angeles, CA, USA
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Prabhakaran MP, Kai D, Ghasemi-Mobarakeh L, Ramakrishna S. Electrospun biocomposite nanofibrous patch for cardiac tissue engineering. Biomed Mater 2011; 6:055001. [PMID: 21813957 DOI: 10.1088/1748-6041/6/5/055001] [Citation(s) in RCA: 108] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A bioengineered construct that matches the chemical, mechanical, biological properties and extracellular matrix morphology of native tissue could be suitable as a cardiac patch for supporting the heart after myocardial infarction. The potential of utilizing a composite nanofibrous scaffold of poly(dl-lactide-co-glycolide)/gelatin (PLGA/Gel) as a biomimetic cardiac patch is studied by culturing a population of cardiomyocyte containing cells on the electrospun scaffolds. The chemical characterization and mechanical properties of the electrospun PLGA and PLGA/Gel nanofibers were studied by Fourier transform infrared spectroscopy, scanning electron microscopy and tensile measurements. The biocompatibility of the scaffolds was also studied and the cardiomyocytes seeded on PLGA/Gel nanofibers were found to express the typical functional cardiac proteins such as alpha-actinin and troponin I, showing the easy integration of cardiomyocytes on PLGA/Gel scaffolds. Our studies strengthen the application of electrospun PLGA/Gel nanofibers as a bio-mechanical support for injured myocardium and as a potential substrate for induction of endogenous cardiomyocyte proliferation, ultimately reducing the cardiac dysfunction and improving cardiac remodeling.
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Affiliation(s)
- Molamma P Prabhakaran
- Health Care and Energy Materials Laboratory, Nanoscience and Nanotechnology Initiative, Faculty of Engineering, National University of Singapore, Singapore.
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40
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Chiang WY, Lai PY, Chan CK. Frequency enhancement in coupled noisy excitable elements. PHYSICAL REVIEW LETTERS 2011; 106:254102. [PMID: 21770642 DOI: 10.1103/physrevlett.106.254102] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Indexed: 05/31/2023]
Abstract
Oscillatory dynamics of coupled excitable FitzHugh-Nagumo elements in the presence of noise is investigated as a function of the coupling strength g. For two such coupled elements, their frequencies are enhanced and will synchronize at a frequency higher than the uncoupled frequencies of each element. As g increases, there is an unexpected peak in the frequency enhancement before reaching synchronization. The results can be understood with an analytic model based on the excitation across a potential barrier whose height is controlled by g. Simulation results of a coupled square lattice can quantitatively reproduce the unexpected peak in the variation of the beating rates observed in cultured cardiac cells experiments.
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Affiliation(s)
- Wei-Yin Chiang
- Department of Physics, Graduate Institute of Biophysics, and Center for Complex Systems, National Central University, Chungli, Taiwan 320, Republic of China
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Thompson SA, Copeland CR, Reich DH, Tung L. Mechanical coupling between myofibroblasts and cardiomyocytes slows electric conduction in fibrotic cell monolayers. Circulation 2011; 123:2083-93. [PMID: 21537003 DOI: 10.1161/circulationaha.110.015057] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND After cardiac injury, activated cardiac myofibroblasts can influence tissue electrophysiology. Because mechanical coupling through adherens junctions provides a route for intercellular communication, we tested the hypothesis that myofibroblasts exert tonic contractile forces on the cardiomyocytes and affect electric propagation via a process of mechanoelectric feedback. METHODS AND RESULTS The role of mechanoelectric feedback was examined in transforming growth factor-β-treated monolayers of cocultured myofibroblasts and neonatal rat ventricular cells by inhibiting myofibroblast contraction and blocking mechanosensitive channels. Untreated (control) and transforming growth factor-β-treated (fibrotic) anisotropic monolayers were optically mapped for electrophysiological comparison. Longitudinal conduction velocity, transverse conduction velocity, and normalized action potential upstroke velocity (dV/dt(max)) significantly decreased in fibrotic monolayers (14.4 ± 0.7 cm/s [mean ± SEM], 4.1 ± 0.3 cm/s [n=53], and 3.1 ± 0.2% per ms [n=14], respectively) compared with control monolayers (27.2 ± 0.8 cm/s, 8.5 ± 0.4 cm/s [n=40], and 4.9 ± 0.1% per ms [n=12], respectively). Application of the excitation-contraction uncoupler blebbistatin or the mechanosensitive channel blocker gadolinium or streptomycin dramatically increased longitudinal conduction velocity, transverse conduction velocity, and dV/dt(max) in fibrotic monolayers (35.9 ± 1.5 cm/s, 10.3 ± 0.6 cm/s [n=17], and 4.5 ± 0.1% per ms [n=14], respectively). Similar results were observed with connexin43-silenced cardiac myofibroblasts. Spiral-wave induction in fibrotic monolayers also decreased after the aforementioned treatments. Finally, traction force measurements of individual myofibroblasts showed a significant increase with transforming growth factor-β, a decrease with blebbistatin, and no change with mechanosensitive channel blockers. CONCLUSIONS These observations suggest that myofibroblast-myocyte mechanical interactions develop during cardiac injury, and that cardiac conduction may be impaired as a result of increased mechanosensitive channel activation owing to tension applied to the myocyte by the myofibroblast.
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Affiliation(s)
- Susan A Thompson
- Department of Biomedical Engineering, The Johns Hopkins University, 720 Rutland Ave, Baltimore, MD 21205, USA
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Shklyar TF, Safronov AP, Toropova OA, Pollack GH, Blyakhman FA. Mechanoelectric potentials in synthetic hydrogels: Possible relation to cytoskeleton. Biophysics (Nagoya-shi) 2011. [DOI: 10.1134/s0006350910060084] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Krenning G, Zeisberg EM, Kalluri R. The origin of fibroblasts and mechanism of cardiac fibrosis. J Cell Physiol 2010; 225:631-7. [PMID: 20635395 DOI: 10.1002/jcp.22322] [Citation(s) in RCA: 468] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Fibroblasts are at the heart of cardiac function and are the principal determinants of cardiac fibrosis. Nevertheless, cardiac fibroblasts remain poorly characterized in molecular terms. Evidence is evolving that the cardiac fibroblast is a highly heterogenic cell population, and that such heterogeneity is caused by the distinct origins of fibroblasts in the heart. Cardiac fibroblasts can derive either from resident fibroblasts, from endothelial cells via an endothelial-mesenchynmal transition or from bone marrow-derived circulating progenitor cells, monocytes and fibrocytes. Here, we review the function and origin of fibroblasts in cardiac fibrosis.NB. The information given is correct.
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Affiliation(s)
- Guido Krenning
- Division of Matrix Biology, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA
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Kamkin A, Kirischuk S, Kiseleva I. Single mechano-gated channels activated by mechanical deformation of acutely isolated cardiac fibroblasts from rats. Acta Physiol (Oxf) 2010; 199:277-92. [PMID: 20102342 DOI: 10.1111/j.1748-1716.2010.02086.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIM Mechanosensitive conductances were reported in cardiac fibroblasts, but the properties of single channels mediating their mechanosensitivity remain uncharacterized. The aim of this work was to investigate single mechano-gated channels (MGCs) activated by mechanical deformations of cardiac fibroblasts. METHODS Currents through single MGCs and mechanosensitive whole-cell currents were recorded from isolated rat atrial fibroblasts using the cell-attached and whole-cell patch-clamp configurations respectively. Defined mechanical stress was applied via the patch pipette used for the whole-cell recordings. RESULTS Under resting conditions occasional short openings of two types of single MGCs with conductances of 43 and 87 pS were observed. Both types of channels displayed a linear current-voltage relationship with the reversal potential around 0 mV. Small (1 microm) mechanical deformations affected neither single nor whole-cell mechano-gated currents. Cell compressions (2, 3 and 4 microm) augmented the whole-cell currents and increased the frequency and duration of single channel openings. Cell stretches (2, 3 and 4 microm) inactivated the whole-cell currents and abolished the activity of single MGCs. Gd(3+) (8 microm) blocked the whole-cell currents within 5 min. No single channel activity was observed in the cell-attached mode when Gd(3+) was added to the intrapipette solution. Cytochalasin D and colchicine (100 microm each) completely blocked both the whole-cell and single channel currents. CONCLUSIONS These findings show that rat atrial fibroblasts express two types of MGCs whose activity is governed by cell deformation. We conclude that fibroblasts can sense the direction of applied stress and contribute to mechano-electrical coupling in the heart.
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Abstract
Cardiac fibroblasts are emerging as key components of normal cardiac function, as well as the response to stressors and injury. These most numerous cells of the heart interact with myocytes via paracrine mechanisms, alterations in extracellular matrix homeostasis, and direct cell-cell interactions. It is possible that they are a contributor to the inability of adult myocytes to proliferate and may influence cardiac progenitor biology. Furthering our understanding of how cardiac fibroblasts and myocytes interact may provide an avenue to novel treatments for heart failure prevention. This review discusses the most recent concepts in cardiac fibroblast-myocyte communication and areas of potential future research.
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Affiliation(s)
- Rahul Kakkar
- Cardiology Division, Massachusetts General Hospital, Department of Medicine, Harvard Medical School, Boston, MA, USA
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46
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Cardiac fibroblasts: at the heart of myocardial remodeling. Pharmacol Ther 2009; 123:255-78. [PMID: 19460403 DOI: 10.1016/j.pharmthera.2009.05.002] [Citation(s) in RCA: 737] [Impact Index Per Article: 49.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2009] [Accepted: 05/05/2009] [Indexed: 12/24/2022]
Abstract
Cardiac fibroblasts are the most prevalent cell type in the heart and play a key role in regulating normal myocardial function and in the adverse myocardial remodeling that occurs with hypertension, myocardial infarction and heart failure. Many of the functional effects of cardiac fibroblasts are mediated through differentiation to a myofibroblast phenotype that expresses contractile proteins and exhibits increased migratory, proliferative and secretory properties. Cardiac myofibroblasts respond to proinflammatory cytokines (e.g. TNFalpha, IL-1, IL-6, TGF-beta), vasoactive peptides (e.g. angiotensin II, endothelin-1, natriuretic peptides) and hormones (e.g. noradrenaline), the levels of which are increased in the remodeling heart. Their function is also modulated by mechanical stretch and changes in oxygen availability (e.g. ischaemia-reperfusion). Myofibroblast responses to such stimuli include changes in cell proliferation, cell migration, extracellular matrix metabolism and secretion of various bioactive molecules including cytokines, vasoactive peptides and growth factors. Several classes of commonly prescribed therapeutic agents for cardiovascular disease also exert pleiotropic effects on cardiac fibroblasts that may explain some of their beneficial outcomes on the remodeling heart. These include drugs for reducing hypertension (ACE inhibitors, angiotensin receptor blockers, beta-blockers), cholesterol levels (statins, fibrates) and insulin resistance (thiazolidinediones). In this review, we provide insight into the properties of cardiac fibroblasts that underscores their importance in the remodeling heart, including their origin, electrophysiological properties, role in matrix metabolism, functional responses to environmental stimuli and ability to secrete bioactive molecules. We also review the evidence suggesting that certain cardiovascular drugs can reduce myocardial remodeling specifically via modulatory effects on cardiac fibroblasts.
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Aranishi H, Kunisawa Y, Komuro T. Characterization of interstitial cells of Cajal in the subserosal layer of the guinea-pig colon. Cell Tissue Res 2008; 335:323-9. [PMID: 19048293 DOI: 10.1007/s00441-008-0730-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2008] [Accepted: 10/29/2008] [Indexed: 10/21/2022]
Abstract
Interstitial cells of Cajal in the subserosa (ICC-SS) of the guinea-pig proximal colon were studied by immunohistochemistry for c-Kit receptors and by transmission electron microscopy. These cells were distributed within a thin layer of connective tissue space immediately beneath the mesothelium and were multipolar with about five primary cytoplasmic processes that divided further into secondary and tertiary processes to form a two-dimensional network. Ultrastructural observations revealed that ICC-SS were connected to each other via gap junctions. They also formed close contacts and peg-and-socket junctions with smooth muscle cells. Three-dimensional analysis of confocal micrographs revealed that the cytoplasmic processes of ICC-SS had contacts with interstitial cells in the longitudinal muscle layer. Taking account of the location and peculiar arrangement of the ICC-SS and the main functions of the proximal colon, i.e. the absorption and transport of fluids, we suggest that the superficial network of ICC-SS acts as a stretch receptor to detect circumferential expansion and swelling of the colon wall and triggers the contraction of the longitudinal muscle to accelerate the drainage of fluids from the colon.
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Affiliation(s)
- Hiromi Aranishi
- Laboratory of Histology and Neuroscience, Department of Health Science and Social Welfare, Faculty of Human Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama 359-1192, Japan
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Fahrenbach JP, Mejia-Alvarez R, Banach K. The relevance of non-excitable cells for cardiac pacemaker function. J Physiol 2007; 585:565-78. [PMID: 17932143 DOI: 10.1113/jphysiol.2007.144121] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Age-dependent changes in the architecture of the sinus node comprise an increasing ratio between fibroblasts and cardiomyocytes. This change is discussed as a potential mechanism for sinus node disease. The goal of this study was to determine the mechanism through which non-excitable cells influence the spontaneous activity of multicellular cardiomyocyte preparations. Cardiomyocyte monolayers (HL-1 cells) or embryonic stem cell-derived cardiomyocytes were used as two- and three-dimensional cardiac pacemaker models. Spontaneous activity and conduction velocity (theta) were monitored by field potential measurements with microelectrode arrays (MEAs). The influence of fibroblasts (WT-fibs) was determined in heterocellular cultures of different cardiomyocyte and fibroblast ratios. The relevance of heterocellular gap junctional coupling was evaluated by the use of fibroblasts deficient for the expression of Cx43 (Cx43(-/-)-fibs). The beating frequency and of heterocellular cultures depended negatively on the fibroblast concentration. Interspersion of fibroblasts in cardiomyocyte monolayers increased the coefficient of the interbeat interval variability. Whereas Cx43(-/-)-fibs decreased theta significantly less than WT-fibs, their effect on the beating frequency and the beat-to-beat variability seemed largely independent of their ability to establish intercellular coupling. These results suggest that electrically integrated, non-excitable cells modulate the excitability of cardiac pacemaker preparations by two distinct mechanisms, one dependent and the other independent of the heterocellular coupling established. Whereas heterocellular coupling enables the fibroblast to depolarize the cardiomyocytes or to act as a current sink, the mere physical separation of the cardiomyocytes by fibroblasts induces bradycardia through a reduction in frequency entrainment.
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Affiliation(s)
- John P Fahrenbach
- University of Illinois at Chicago, Department of Medicine/Section Cardiology, 840 S. Wood Street (M/C 715), Chicago, IL 60612, USA
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Baruscotti M, Robinson RB. Electrophysiology and pacemaker function of the developing sinoatrial node. Am J Physiol Heart Circ Physiol 2007; 293:H2613-23. [PMID: 17827259 DOI: 10.1152/ajpheart.00750.2007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The sinoatrial node performs its task as a cardiac impulse generator throughout the life of the organism, but this important function is not a constant. Rather, there are significant developmental changes in the expression and function of ion channels and other cellular elements, which lead to a postnatal slowing of heart rate and may be crucial to the reliable functioning of the node during maturation. In this review, we provide an overview of current knowledge regarding these changes, with the main focus placed on maturation of the ion channel expression profile. Studies on Na(+) and pacemaker currents have shown that their contribution to automaticity is greater in the newborn than in the adult, but this age-dependent decrease is at least partially opposed by an increased contribution of L-type Ca(2+) current. Whereas information regarding age-dependent changes in other transmembrane currents within the sinoatrial node are lacking, there are data on other relevant parameters. These include an increase in the nodal content of fibroblasts and in the area of nonexpression of connexin43, considered a molecular marker of nodal tissue. Although much remains to be done before a comprehensive view of the developmental biology of the node is available, important evidence in support of a molecular interpretation of developmental slowing of the intrinsic sinoatrial rate is beginning to emerge.
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Affiliation(s)
- Mirko Baruscotti
- Laboratory of Molecular Physiology and Neurobiology, Department of Biomolecular Sciences and Biotechnology, University of Milano, Milan, Italy
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Pandit SV, Jalife J. Aging and atrial fibrillation research: where we are and where we should go. Heart Rhythm 2006; 4:186-7. [PMID: 17275754 PMCID: PMC1849951 DOI: 10.1016/j.hrthm.2006.11.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2006] [Indexed: 10/23/2022]
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