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Câmara BO, Guimarães JG, Pereira Junior ML. Analog neuromorphic circuit for spontaneous Ca 2+ oscillations. Sci Rep 2023; 13:20107. [PMID: 37973824 PMCID: PMC10654768 DOI: 10.1038/s41598-023-47433-w] [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: 05/11/2023] [Accepted: 11/14/2023] [Indexed: 11/19/2023] Open
Abstract
This study proposes an innovative analog neuromorphic circuit design to mimic spontaneous Ca2+ oscillations observed in astrocytes. Unlike traditional models, this approach does not rely on synaptic stimulation, suggesting that astrocytes may play a key role in generating neuronal activity. The circuit is built using transistor differential pairs to approximate the nonlinear sigmoidal biological functions, and its performance is validated through simulation and compared against mathematical models using phase diagram analysis. Results indicate a good fit between the circuit and the mathematical model. Finally, the circuit's ability to simulate the release of glutamate and ATP through spontaneous oscillations is demonstrated.
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Affiliation(s)
- Beatriz O Câmara
- Department of Electrical Engineering, Faculty of Technology, University of Brasília, 70910-900, Brasília, Brazil
| | - Janaina G Guimarães
- Federal University of Santa Catarina, Control Engineering, Automation and Computer Science, 89036-256, Blumenau, Santa Catarina, Brazil
| | - Marcelo L Pereira Junior
- Department of Electrical Engineering, Faculty of Technology, University of Brasília, 70910-900, Brasília, Brazil.
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2
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Hernández-Del-Valle M, Valencia-Expósito A, López-Izquierdo A, Casanova-Ferrer P, Tarazona P, Martín-Bermudo MD, Míguez DG. A coarse-grained approach to model the dynamics of the actomyosin cortex. BMC Biol 2022; 20:90. [PMID: 35459165 PMCID: PMC9034637 DOI: 10.1186/s12915-022-01279-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Accepted: 03/11/2022] [Indexed: 01/21/2023] Open
Abstract
Background The dynamics of the actomyosin machinery is at the core of many important biological processes. Several relevant cellular responses such as the rhythmic compression of the cell cortex are governed, at a mesoscopic level, by the nonlinear interaction between actin monomers, actin crosslinkers, and myosin motors. Coarse-grained models are an optimal tool to study actomyosin systems, since they can include processes that occur at long time and space scales, while maintaining the most relevant features of the molecular interactions. Results Here, we present a coarse-grained model of a two-dimensional actomyosin cortex, adjacent to a three-dimensional cytoplasm. Our simplified model incorporates only well-characterized interactions between actin monomers, actin crosslinkers and myosin, and it is able to reproduce many of the most important aspects of actin filament and actomyosin network formation, such as dynamics of polymerization and depolymerization, treadmilling, network formation, and the autonomous oscillatory dynamics of actomyosin. Conclusions We believe that the present model can be used to study the in vivo response of actomyosin networks to changes in key parameters of the system, such as alterations in the attachment of actin filaments to the cell cortex. Supplementary Information The online version contains supplementary material available at (10.1186/s12915-022-01279-2).
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Affiliation(s)
- Miguel Hernández-Del-Valle
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, 28049, Spain.,IFIMAC, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain.,Instituto Nicolás Cabrera, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain.,Fisica de la Materia Condensada, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain
| | - Andrea Valencia-Expósito
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide/CSIC/JA, Carretera de Utrera km 1, Seville, 41013, Spain
| | - Antonio López-Izquierdo
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, 28049, Spain.,IFIMAC, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain.,Instituto Nicolás Cabrera, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain.,Fisica de la Materia Condensada, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain
| | - Pau Casanova-Ferrer
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, 28049, Spain.,IFIMAC, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain.,Instituto Nicolás Cabrera, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain.,Fisica de la Materia Condensada, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain
| | - Pedro Tarazona
- IFIMAC, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain.,Instituto Nicolás Cabrera, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain.,Fisica Teórica de la Materia Condensada, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain
| | - Maria D Martín-Bermudo
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide/CSIC/JA, Carretera de Utrera km 1, Seville, 41013, Spain
| | - David G Míguez
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Madrid, 28049, Spain. .,IFIMAC, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain. .,Instituto Nicolás Cabrera, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain. .,Fisica de la Materia Condensada, Fac. de Ciencias, Universidad Autónoma de Madrid, Madrid, 28049, Spain.
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3
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DiFrancesco ML, Mesirca P, Bidaud I, Isbrandt D, Mangoni ME. The funny current in genetically modified mice. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2021; 166:39-50. [PMID: 34129872 DOI: 10.1016/j.pbiomolbio.2021.06.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 05/18/2021] [Accepted: 06/07/2021] [Indexed: 12/27/2022]
Abstract
Since its first description in 1979, the hyperpolarization-activated funny current (If) has been the object of intensive research aimed at understanding its role in cardiac pacemaker activity and its modulation by the sympathetic and parasympathetic branches of the autonomic nervous system. If was described in isolated tissue strips of the rabbit sinoatrial node using the double-electrode voltage-clamp technique. Since then, the rabbit has been the principal animal model for studying pacemaker activity and If for more than 20 years. In 2001, the first study describing the electrophysiological properties of mouse sinoatrial pacemaker myocytes and those of If was published. It was soon followed by the description of murine myocytes of the atrioventricular node and the Purkinje fibres. The sinoatrial node of genetically modified mice has become a very popular model for studying the mechanisms of cardiac pacemaker activity. This field of research benefits from the impressive advancement of in-vivo exploration techniques of physiological parameters, imaging, genetics, and large-scale genomic approaches. The present review discusses the influence of mouse genetic on the most recent knowledge of the funny current's role in the physiology and pathophysiology of cardiac pacemaker activity. Genetically modified mice have provided important insights into the role of If in determining intrinsic automaticity in vivo and in myocytes of the conduction system. In addition, gene targeting of f-(HCN) channel isoforms have contributed to elucidating the current's role in the regulation of heart rate by the parasympathetic nervous system. This review is dedicated to Dario DiFrancesco on his retirement.
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Affiliation(s)
- Mattia L DiFrancesco
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genoa, Italy; IRCCS Ospedale Policlinico San Martino, Genoa, Italy; Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France; LabEx Ion Channels Science and Therapeutics (ICST), France.
| | - Pietro Mesirca
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France; LabEx Ion Channels Science and Therapeutics (ICST), France
| | - Isabelle Bidaud
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France; LabEx Ion Channels Science and Therapeutics (ICST), France
| | - Dirk Isbrandt
- Deutsches Zentrum für Neurodegenerative Erktankungen (DZNE), Bonn, Germany; University of Cologne, Institute for Molecular and Behavioral Neuroscience, Cologne, Germany
| | - Matteo E Mangoni
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France; LabEx Ion Channels Science and Therapeutics (ICST), France.
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4
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Tissue Chips and Microphysiological Systems for Disease Modeling and Drug Testing. MICROMACHINES 2021; 12:mi12020139. [PMID: 33525451 PMCID: PMC7911320 DOI: 10.3390/mi12020139] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/23/2021] [Accepted: 01/26/2021] [Indexed: 12/15/2022]
Abstract
Tissue chips (TCs) and microphysiological systems (MPSs) that incorporate human cells are novel platforms to model disease and screen drugs and provide an alternative to traditional animal studies. This review highlights the basic definitions of TCs and MPSs, examines four major organs/tissues, identifies critical parameters for organization and function (tissue organization, blood flow, and physical stresses), reviews current microfluidic approaches to recreate tissues, and discusses current shortcomings and future directions for the development and application of these technologies. The organs emphasized are those involved in the metabolism or excretion of drugs (hepatic and renal systems) and organs sensitive to drug toxicity (cardiovascular system). This article examines the microfluidic/microfabrication approaches for each organ individually and identifies specific examples of TCs. This review will provide an excellent starting point for understanding, designing, and constructing novel TCs for possible integration within MPS.
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Go YH, Kim J, Jeong HC, Kim SM, Kim YJ, Park SJ, Moon SH, Cha HJ. Luteolin Induces Selective Cell Death of Human Pluripotent Stem Cells. Biomedicines 2020; 8:biomedicines8110453. [PMID: 33121085 PMCID: PMC7692041 DOI: 10.3390/biomedicines8110453] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 10/20/2020] [Accepted: 10/25/2020] [Indexed: 11/16/2022] Open
Abstract
Despite recent advances in clinical stem cell therapy applications based on human pluripotent stem cells (hPSCs), potential teratoma formation due to the presence of residual undifferentiated hPSCs remains a serious risk factor that challenges widespread clinical application. To overcome this risk, a variety of approaches have been developed to eliminate the remaining undifferentiated hPSCs via selective cell death induction. Our study seeks to identify natural flavonoids that are more potent than quercetin (QC), to selectively induce hPSC death. Upon screening in-house flavonoids, luteolin (LUT) is found to be more potent than QC to eliminate hPSCs in a p53-dependent manner, but not hPSC-derived smooth muscle cells or perivascular progenitor cells. Particularly, treating human embryonic stem cell (hESC)-derived cardiomyocytes with LUT efficiently eliminates the residual hESCs and only results in marginal effects on cardiomyocyte (CM) functions, as determined by calcium influx. Considering the technical limitations of isolating CMs due to a lack of exclusive surface markers at the end of differentiation, LUT treatment is a promising approach to minimize teratoma formation risk.
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Affiliation(s)
- Young-Hyun Go
- Department of Life Science, Sogang University, Seoul 04107, Korea; (Y.-H.G.); (H.-C.J.)
| | - Jumee Kim
- College of Pharmacy, Seoul National University, Seoul 08826, Korea; (J.K.); (S.-M.K.); (Y.-J.K.)
| | - Ho-Chang Jeong
- Department of Life Science, Sogang University, Seoul 04107, Korea; (Y.-H.G.); (H.-C.J.)
| | - Seong-Min Kim
- College of Pharmacy, Seoul National University, Seoul 08826, Korea; (J.K.); (S.-M.K.); (Y.-J.K.)
| | - Yun-Jeong Kim
- College of Pharmacy, Seoul National University, Seoul 08826, Korea; (J.K.); (S.-M.K.); (Y.-J.K.)
| | - Soon-Jung Park
- Stem Cell Research Institute, T&R Biofab Co., Ltd., Siheung 15073, Korea; (S.-J.P.); (S.-H.M.)
| | - Sung-Hwan Moon
- Stem Cell Research Institute, T&R Biofab Co., Ltd., Siheung 15073, Korea; (S.-J.P.); (S.-H.M.)
| | - Hyuk-Jin Cha
- College of Pharmacy, Seoul National University, Seoul 08826, Korea; (J.K.); (S.-M.K.); (Y.-J.K.)
- Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Korea
- Correspondence: ; Tel.: +82-2-880-7825; Fax: +82-2-880-9122
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Marchal GA, Verkerk AO, Mohan RA, Wolswinkel R, Boukens BJD, Remme CA. The sodium channel Na V 1.5 impacts on early murine embryonic cardiac development, structure and function in a non-electrogenic manner. Acta Physiol (Oxf) 2020; 230:e13493. [PMID: 32386467 PMCID: PMC7539970 DOI: 10.1111/apha.13493] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 04/15/2020] [Accepted: 05/01/2020] [Indexed: 12/19/2022]
Abstract
AIM The voltage-gated sodium channel NaV 1.5, encoded by SCN5A, is essential for cardiac excitability and ensures proper electrical conduction. Early embryonic death has been observed in several murine models carrying homozygous Scn5amutations. We investigated when sodium current (INa ) becomes functionally relevant in the murine embryonic heart and how Scn5a/NaV 1.5 dysfunction impacts on cardiac development. METHODS Involvement of NaV 1.5-generated INa in murine cardiac electrical function was assessed by optical mapping in wild type (WT) embryos (embryonic day (E)9.5 and E10.5) in the absence and presence of the sodium channel blocker tetrodotoxin (30 µmol/L). INa was assessed by patch-clamp analysis in cardiomyocytes isolated from WT embryos (E9.5-17.5). In addition, cardiac morphology and electrical function was assessed in Scn5a-1798insD-/- embryos (E9.5-10.5) and their WT littermates. RESULTS In WT embryos, tetrodotoxin did not affect cardiac activation at E9.5, but slowed activation at E10.5. Accordingly, patch-clamp measurements revealed that INa was virtually absent at E9.5 but robustly present at E10.5. Scn5a-1798insD-/- embryos died in utero around E10.5, displaying severely affected cardiac activation and morphology. Strikingly, altered ventricular activation was observed in Scn5a-1798insD-/- E9.5 embryos before the onset of INa , in addition to reduced cardiac tissue volume compared to WT littermates. CONCLUSION We here demonstrate that NaV 1.5 is involved in cardiac electrical function from E10.5 onwards. Scn5a-1798insD-/- embryos displayed cardiac structural abnormalities at E9.5, indicating that NaV 1.5 dysfunction impacts on embryonic cardiac development in a non-electrogenic manner. These findings are potentially relevant for understanding structural defects observed in relation to NaV 1.5 dysfunction.
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Affiliation(s)
- Gerard A. Marchal
- Department of Experimental Cardiology Amsterdam UMC (location Academic Medical Center) Amsterdam the Netherlands
| | - Arie O. Verkerk
- Department of Experimental Cardiology Amsterdam UMC (location Academic Medical Center) Amsterdam the Netherlands
- Department of Medical Biology Amsterdam UMC (location Academic Medical Center) Amsterdam the Netherlands
| | - Rajiv A. Mohan
- Department of Experimental Cardiology Amsterdam UMC (location Academic Medical Center) Amsterdam the Netherlands
- Department of Medical Biology Amsterdam UMC (location Academic Medical Center) Amsterdam the Netherlands
| | - Rianne Wolswinkel
- Department of Experimental Cardiology Amsterdam UMC (location Academic Medical Center) Amsterdam the Netherlands
| | - Bastiaan J. D. Boukens
- Department of Medical Biology Amsterdam UMC (location Academic Medical Center) Amsterdam the Netherlands
| | - Carol Ann Remme
- Department of Experimental Cardiology Amsterdam UMC (location Academic Medical Center) Amsterdam the Netherlands
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7
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Marchena M, Echebarria B, Shiferaw Y, Alvarez-Lacalle E. Buffering and total calcium levels determine the presence of oscillatory regimes in cardiac cells. PLoS Comput Biol 2020; 16:e1007728. [PMID: 32970668 PMCID: PMC7537911 DOI: 10.1371/journal.pcbi.1007728] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 10/06/2020] [Accepted: 07/07/2020] [Indexed: 12/16/2022] Open
Abstract
Calcium oscillations and waves induce depolarization in cardiac cells which are believed to cause life-threathening arrhythimas. In this work, we study the conditions for the appearance of calcium oscillations in both a detailed subcellular model of calcium dynamics and a minimal model that takes into account just the minimal ingredients of the calcium toolkit. To avoid the effects of homeostatic changes and the interaction with the action potential we consider the somewhat artificial condition of a cell without pacing and with no calcium exchange with the extracellular medium. Both the full subcellular model and the minimal model present the same scenarios depending on the calcium load: two stationary states, one with closed ryanodine receptors (RyR) and most calcium in the cell stored in the sarcoplasmic reticulum (SR), and another, with open RyRs and a depleted SR. In between, calcium oscillations may appear. The robustness of these oscillations is determined by the amount of calsequestrin (CSQ). The lack of this buffer in the SR enhances the appearance of oscillations. The minimal model allows us to relate the stability of the oscillating state to the nullcline structure of the system, and find that its range of existence is bounded by a homoclinic and a Hopf bifurcation, resulting in a sudden transition to the oscillatory regime as the cell calcium load is increased. Adding a small amount of noise to the RyR behavior increases the parameter region where oscillations appear and provides a gradual transition from the resting state to the oscillatory regime, as observed in the subcellular model and experimentally. In cardiac cells, calcium plays a very important role. An increase in calcium levels is the trigger used by the cell to initiate contraction. Besides, calcium modulates several transmembrane currents, affecting the cell transmembrane potential. Thus, dysregulations in calcium handling have been associated with the appearance of arrhythmias. Often, this dysregulation results in the appearance of periodic calcium waves or global oscillations, providing a pro-arrhythmic substrate. In this paper, we study the onset of calcium oscillations in cardiac cells using both a detailed subcellular model of calcium dynamics and a minimal model that takes into account the essential ingredients of the calcium toolkit. Both reproduce the main experimental results and link this behavior with the presence of different steady-state solutions and bifurcations that depend on the total amount of calcium in the cell and in the level of buffering present. We expect that this work will help to clarify the conditions under which calcium oscillations appear in cardiac myocytes and, therefore, will represent a step further in the understanding of the origin of cardiac arrhythmias.
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Affiliation(s)
- Miquel Marchena
- Departament de Física, Universitat Politècnica de Catalunya-BarcelonaTech, Barcelona, Spain
| | - Blas Echebarria
- Departament de Física, Universitat Politècnica de Catalunya-BarcelonaTech, Barcelona, Spain
| | - Yohannes Shiferaw
- Physics Department, California State University, Northridge, California 91330, USA
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Tyser RCV, Srinivas S. The First Heartbeat-Origin of Cardiac Contractile Activity. Cold Spring Harb Perspect Biol 2020; 12:cshperspect.a037135. [PMID: 31767652 DOI: 10.1101/cshperspect.a037135] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The amniote embryonic heart starts as a crescent of mesoderm that transitions through a midline linear heart tube in the course of developing into the four chambered heart. It is unusual in having to contract rhythmically while still undergoing extensive morphogenetic remodeling. Advances in imaging have allowed us to determine when during development this contractile activity starts. In the mouse, focal regions of contractions can be detected as early as the cardiac crescent stage. Calcium transients, required to trigger contraction, can be detected even earlier, prior to contraction. In this review, we outline what is currently known about how this early contractile function is initiated and the impact early contractile function has on cardiac development.
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Affiliation(s)
- Richard C V Tyser
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, United Kingdom
| | - Shankar Srinivas
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, United Kingdom
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Hazari MAH. Intracellular divalent ion oscillations: Is this the key phenomenon in rhythm generators? ANNALS OF MEDICAL PHYSIOLOGY 2019; 3:19-20. [DOI: 10.23921/amp.2019v3i2.54657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/31/2024]
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10
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Karppinen S, Hänninen SL, Rapila R, Tavi P. Sarcoplasmic reticulum Ca 2+ -induced Ca 2+ release regulates class IIa HDAC localization in mouse embryonic cardiomyocytes. Physiol Rep 2019; 6. [PMID: 29380950 PMCID: PMC5789715 DOI: 10.14814/phy2.13522] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 10/28/2017] [Accepted: 10/30/2017] [Indexed: 11/24/2022] Open
Abstract
In embryonic cardiomyocytes, sarcoplasmic reticulum (SR)‐derived Ca2+ release is required to induce Ca2+ oscillations for contraction and to control cardiac development through Ca2+‐activated pathways. Here, our aim was to study how SR Ca2+ release regulates cytosolic and nuclear Ca2+ distribution and the subsequent effects on the Ca2+‐dependent localization of class IIa histone deacetylases (HDAC) and cardiac‐specific gene expression in embryonic cardiomyocytes. Confocal microscopy was used to study changes in Ca2+‐distribution and localization of immunolabeled HDAC4 and HDAC5 upon changes in SR Ca2+ release in mouse embryonic cardiomyocytes. Dynamics of translocation were also observed with a confocal microscope, using HDAC5‐green fluorescent protein transfected myocytes. Expression of class IIa HDACs in differentiating myocytes and changes in cardiac‐specific gene expression were studied using real‐time quantitative PCR. Inhibition of SR Ca2+ release caused a significant decrease in intranuclear Ca2+ concentration, a rapid nuclear import of HDAC5 and subnuclear redistribution of HDAC4. Endogenous localization of HDAC5 and HDAC4 was mostly cytosolic and at the nuclear periphery, respectively. Downregulated expression of cardiac‐specific genes was also observed upon SR Ca2+ release inhibition. Electrical stimulation of sarcolemmal Ca2+ influx was not sufficient to rescue either the HDAC localization or the gene expression changes. SR Ca2+ release controls subcellular Ca2+ distribution and regulates localization of HDAC4 and HDAC5 in embryonic cardiomyocytes. Changes in SR Ca2+ release also caused changes in expression of the developmental phase‐specific genes, which may be due to the changes in HDAC‐localization.
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Affiliation(s)
- Sari Karppinen
- Department of Biotechnology and Molecular Medicine, A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Sandra L Hänninen
- Institute of Biomedicine, Department of Physiology and Biocenter Oulu, University of Oulu, Finland
| | - Risto Rapila
- Department of Biotechnology and Molecular Medicine, A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Pasi Tavi
- Department of Biotechnology and Molecular Medicine, A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
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Rebuzzini P, Zuccolo E, Civello C, Fassina L, Arechaga J, Izquierdo A, Faris P, Zuccotti M, Moccia F, Garagna S. Polychlorinated biphenyls reduce the kinematics contractile properties of embryonic stem cells-derived cardiomyocytes by disrupting their intracellular Ca 2+ dynamics. Sci Rep 2018; 8:17909. [PMID: 30559452 PMCID: PMC6297156 DOI: 10.1038/s41598-018-36333-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 11/19/2018] [Indexed: 12/11/2022] Open
Abstract
Persistent organic pollutants are a group of chemicals that include polychlorinated biphenyls (PCBs). PCBs exposure during adult life increases incidence and severity of cardiomyopathies, whereas in utero exposure determines congenital heart defects. Being fat-soluble, PCBs are passed to newborns through maternal milk, impairing heart functionality in the adult. It is still unknown how PCBs impair cardiac contraction at cellular/molecular levels. Here, we study the molecular mechanisms by which PCBs cause the observed heart contraction defects, analysing the alterations of Ca2+ toolkit components that regulate contraction. We investigated the effect that Aroclor 1254 (Aroclor), a mixture of PCBs, has on perinatal-like cardiomyocytes derived from mouse embryonic stem cells. Cardiomyocytes, exposed to 1 or 2 µg/ml Aroclor for 24 h, were analyzed for their kinematics contractile properties and intracellular Ca2+ dynamics. We observed that Aroclor impairs cardiomyocytes contractile properties by inhibiting spontaneous Ca2+ oscillations. It disrupts intracellular Ca2+ homeostasis by reducing the sarcoplasmic reticulum Ca2+ content and by inhibiting voltage-gated Ca2+ entry. These findings contribute to the understanding of the molecular underpinnings of PCBs-induced cardiovascular alterations, which are emerging as an additional life-threatening hurdle associated to PCBs pollution. Therefore, PCBs-dependent alteration of intracellular Ca2+ dynamics is the most likely trigger of developmental cardiac functional alteration.
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Affiliation(s)
- Paola Rebuzzini
- Laboratorio di Biologia dello Sviluppo, Dipartimento di Biologia e Biotecnologie, Università degli Studi di Pavia, Pavia, Italy. .,Centre for Health Technologies (C.H.T.), Università degli Studi di Pavia, Pavia, Italy.
| | - Estella Zuccolo
- Laboratorio di Fisiologia Generale, Dipartimento di Biologia e Biotecnologie, Università degli Studi di Pavia, Pavia, Italy
| | - Cinzia Civello
- Laboratorio di Biologia dello Sviluppo, Dipartimento di Biologia e Biotecnologie, Università degli Studi di Pavia, Pavia, Italy
| | - Lorenzo Fassina
- Centre for Health Technologies (C.H.T.), Università degli Studi di Pavia, Pavia, Italy.,Dipartimento di Ingegneria Industriale e dell'Informazione, Università degli Studi di Pavia, Pavia, Italy
| | - Juan Arechaga
- Laboratory of Stem Cells, Development and Cancer, Department of Cell Biology and Histology, Faculty of Medicine and Nursing, Universidad del País Vasco, Vizcaya, Spain
| | - Amaia Izquierdo
- Laboratory of Stem Cells, Development and Cancer, Department of Cell Biology and Histology, Faculty of Medicine and Nursing, Universidad del País Vasco, Vizcaya, Spain
| | - Pawan Faris
- Laboratorio di Fisiologia Generale, Dipartimento di Biologia e Biotecnologie, Università degli Studi di Pavia, Pavia, Italy.,Department of Biology, College of Science, Salahaddin University, Erbil, Kurdistan-Region of Iraq, Iraq
| | - Maurizio Zuccotti
- Laboratorio di Biologia dello Sviluppo, Dipartimento di Biologia e Biotecnologie, Università degli Studi di Pavia, Pavia, Italy. .,Centre for Health Technologies (C.H.T.), Università degli Studi di Pavia, Pavia, Italy.
| | - Francesco Moccia
- Laboratorio di Fisiologia Generale, Dipartimento di Biologia e Biotecnologie, Università degli Studi di Pavia, Pavia, Italy
| | - Silvia Garagna
- Laboratorio di Biologia dello Sviluppo, Dipartimento di Biologia e Biotecnologie, Università degli Studi di Pavia, Pavia, Italy. .,Centre for Health Technologies (C.H.T.), Università degli Studi di Pavia, Pavia, Italy.
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12
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Action potential-based MEA platform for in vitro screening of drug-induced cardiotoxicity using human iPSCs and rat neonatal myocytes. J Pharmacol Toxicol Methods 2017; 87:48-52. [DOI: 10.1016/j.vascn.2017.05.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 05/10/2017] [Accepted: 05/20/2017] [Indexed: 11/22/2022]
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Yoon MN, Kim MJ, Koong HS, Kim DK, Kim SH, Park HS. Ethanol suppresses carbamylcholine-induced intracellular calcium oscillation in mouse pancreatic acinar cells. Alcohol 2017; 63:53-59. [PMID: 28847382 DOI: 10.1016/j.alcohol.2017.03.006] [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: 09/19/2016] [Revised: 03/23/2017] [Accepted: 03/23/2017] [Indexed: 12/31/2022]
Abstract
Oscillation of intracellular calcium levels is closely linked to initiating secretion of digestive enzymes from pancreatic acinar cells. Excessive alcohol consumption is known to relate to a variety of disorders in the digestive system, including the exocrine pancreas. In this study, we have investigated the role and mechanism of ethanol on carbamylcholine (CCh)-induced intracellular calcium oscillation in murine pancreatic acinar cells. Ethanol at concentrations of 30 and 100 mM reversibly suppressed CCh-induced Ca2+ oscillation in a dose-dependent manner. Pretreatment of ethanol has no effect on the store-operated calcium entry induced by 10 μM of CCh. Ethanol significantly reduced the initial calcium peak induced by low concentrations of CCh and therefore, the CCh-induced dose-response curve of the initial calcium peak was shifted to the right by ethanol pretreatment. Furthermore, ethanol significantly dose-dependently reduced inositol 1,4,5-trisphosphate-induced calcium release from the internal stores in permeabilized acinar cells. These results provide evidence that excessive alcohol intake could impair cytosolic calcium oscillation through inhibiting calcium release from intracellular stores in mouse pancreatic acinar cells.
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Affiliation(s)
- Mi Na Yoon
- Department of Physiology, College of Medicine, Konyang University, Daejeon 35365, Republic of Korea
| | - Min Jae Kim
- Department of Physiology, College of Medicine, Konyang University, Daejeon 35365, Republic of Korea
| | - Hwa Soo Koong
- Department of Dental Hygiene, College of Medical Science, Konyang University, Daejeon 35365, Republic of Korea
| | - Dong Kwan Kim
- Department of Physiology, College of Medicine, Konyang University, Daejeon 35365, Republic of Korea
| | - Se Hoon Kim
- Department of Physiology, College of Medicine, Konyang University, Daejeon 35365, Republic of Korea
| | - Hyung Seo Park
- Department of Physiology, College of Medicine, Konyang University, Daejeon 35365, Republic of Korea; Myunggok Medical Research Institute, Konyang University, Daejeon 35365, Republic of Korea.
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14
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Tyser RC, Miranda AM, Chen CM, Davidson SM, Srinivas S, Riley PR. Calcium handling precedes cardiac differentiation to initiate the first heartbeat. eLife 2016; 5. [PMID: 27725084 PMCID: PMC5059139 DOI: 10.7554/elife.17113] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 09/13/2016] [Indexed: 11/30/2022] Open
Abstract
The mammalian heartbeat is thought to begin just prior to the linear heart tube stage of development. How the initial contractions are established and the downstream consequences of the earliest contractile function on cardiac differentiation and morphogenesis have not been described. Using high-resolution live imaging of mouse embryos, we observed randomly distributed spontaneous asynchronous Ca2+-oscillations (SACOs) in the forming cardiac crescent (stage E7.75) prior to overt beating. Nascent contraction initiated at around E8.0 and was associated with sarcomeric assembly and rapid Ca2+ transients, underpinned by sequential expression of the Na+-Ca2+ exchanger (NCX1) and L-type Ca2+ channel (LTCC). Pharmacological inhibition of NCX1 and LTCC revealed rapid development of Ca2+ handling in the early heart and an essential early role for NCX1 in establishing SACOs through to the initiation of beating. NCX1 blockade impacted on CaMKII signalling to down-regulate cardiac gene expression, leading to impaired differentiation and failed crescent maturation. DOI:http://dx.doi.org/10.7554/eLife.17113.001 The heart is the first organ to form and to begin working in an embryo during pregnancy. It must begin pumping early to supply oxygen and nutrients to the developing embryo. Coordinated contractions of specialised muscle cells in the heart, called cardiomyocytes, generate the force needed to pump blood. The flow of calcium ions into and out of the cardiomyocytes triggers these heartbeats. In addition to triggering heart contractions, calcium ions also act as a messenger that drives changes in which genes are active in the cardiomyocytes and how these cells behave. Scientists commonly think of the first heartbeat as occurring after a tube-like structure forms in the embryo that will eventually develop into the heart. However, it is not yet clear how the first heartbeat starts or how the initial heartbeats affect further heart development. Tyser, Miranda et al. now show that the first heartbeat actually occurs much earlier in embryonic development than widely appreciated. In the experiments, videos of live mouse embryos showed that prior to the first heartbeat the flow of calcium ions between different cardiomyocytes is not synchronised. However, as the heart grows these calcium flows become coordinated leading to the first heartbeat. The heartbeats also become faster as the heart grows. Using drugs to block the movement of calcium ions, Tyser, Miranda et al. also show that a protein called NCX1 is required to trigger the calcium flows prior to the first heartbeat. Moreover, the experiments revealed that these early heartbeats help drive the growth of cardiomyocytes and shape the developing heart. Together, the experiments show that the first heartbeats are essential for normal heart development. Future studies are needed to determine what controls the speed of the first heartbeats, and what organises the calcium flows that trigger the first heartbeat. Such studies may help scientists better understand birth defects of the heart, and may suggest strategies to rebuild hearts that have been damaged by a heart attack or other injury. DOI:http://dx.doi.org/10.7554/eLife.17113.002
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Affiliation(s)
- Richard Cv Tyser
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom.,The Hatter Cardiovascular Institute, University College London and Medical School, London, United Kingdom
| | - Antonio Ma Miranda
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | | | - Sean M Davidson
- The Hatter Cardiovascular Institute, University College London and Medical School, London, United Kingdom
| | - Shankar Srinivas
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Paul R Riley
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
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15
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Wheeler RJ. Analyzing the dynamics of cell cycle processes from fixed samples through ergodic principles. Mol Biol Cell 2016; 26:3898-903. [PMID: 26543196 PMCID: PMC4710220 DOI: 10.1091/mbc.e15-03-0151] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Tools to analyze cyclical cellular processes, particularly the cell cycle, are of broad value for cell biology. Cell cycle synchronization and live-cell time-lapse observation are widely used to analyze these processes but are not available for many systems. Simple mathematical methods built on the ergodic principle are a well-established, widely applicable, and powerful alternative analysis approach, although they are less widely used. These methods extract data about the dynamics of a cyclical process from a single time-point “snapshot” of a population of cells progressing through the cycle asynchronously. Here, I demonstrate application of these simple mathematical methods to analysis of basic cyclical processes—cycles including a division event, cell populations undergoing unicellular aging, and cell cycles with multiple fission (schizogony)—as well as recent advances that allow detailed mapping of the cell cycle from continuously changing properties of the cell such as size and DNA content. This includes examples using existing data from mammalian, yeast, and unicellular eukaryotic parasite cell biology. Through the ongoing advances in high-throughput cell analysis by light microscopy, electron microscopy, and flow cytometry, these mathematical methods are becoming ever more important and are a powerful complementary method to traditional synchronization and time-lapse cell cycle analysis methods.
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Affiliation(s)
- Richard John Wheeler
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom, and Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
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16
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Radaszkiewicz KA, Sýkorová D, Karas P, Kudová J, Kohút L, Binó L, Večeřa J, Víteček J, Kubala L, Pacherník J. Simple non-invasive analysis of embryonic stem cell-derived cardiomyocytes beating in vitro. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:024301. [PMID: 26931869 DOI: 10.1063/1.4941776] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The analysis of digital video output enables the non-invasive screening of various active biological processes. For the monitoring and computing of the beating parameters of cardiomyocytes in vitro, CB Analyser (cardiomyocyte beating analyser) software was developed. This software is based on image analysis of the video recording of beating cardiomyocytes. CB Analyser was tested using cardiomyocytes derived from mouse embryonic stem cells at different stages of cardiomyogenesis. We observed that during differentiation (from day 18), the beat peak width decreased, which corresponded to the increased speed of an individual pulse. However, the beating frequency did not change. Further, the effects of epinephrine modulating mature cardiomyocyte functions were tested to validate the CB Analyser analysis. In conclusion, data show that CB Analyser is a useful tool for evaluating the functions of both developing and mature cardiomyocytes under various conditions in vitro.
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Affiliation(s)
| | - Dominika Sýkorová
- Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Pavel Karas
- Centre for Biomedical Image Analysis, Faculty of Informatics, Masaryk University, Brno, Czech Republic
| | - Jana Kudová
- Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Lukáš Kohút
- Research Center for Toxic Compounds in the Environment, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Lucia Binó
- Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Josef Večeřa
- Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Jan Víteček
- Institute of Biophysics ASCR v.v.i., Brno, Czech Republic
| | - Lukáš Kubala
- Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Jiří Pacherník
- Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
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17
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Thiesler CT, Cajic S, Hoffmann D, Thiel C, van Diepen L, Hennig R, Sgodda M, Weiβmann R, Reichl U, Steinemann D, Diekmann U, Huber NMB, Oberbeck A, Cantz T, Kuss AW, Körner C, Schambach A, Rapp E, Buettner FFR. Glycomic Characterization of Induced Pluripotent Stem Cells Derived from a Patient Suffering from Phosphomannomutase 2 Congenital Disorder of Glycosylation (PMM2-CDG). Mol Cell Proteomics 2016; 15:1435-52. [PMID: 26785728 PMCID: PMC4824866 DOI: 10.1074/mcp.m115.054122] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Indexed: 01/08/2023] Open
Abstract
PMM2-CDG, formerly known as congenital disorder of glycosylation-Ia (CDG-Ia), is caused by mutations in the gene encoding phosphomannomutase 2 (PMM2). This disease is the most frequent form of inherited CDG-diseases affecting protein N-glycosylation in human. PMM2-CDG is a multisystemic disease with severe psychomotor and mental retardation. In order to study the pathophysiology of PMM2-CDG in a human cell culture model, we generated induced pluripotent stem cells (iPSCs) from fibroblasts of a PMM2-CDG-patient (PMM2-iPSCs). Expression of pluripotency factors and in vitro differentiation into cell types of the three germ layers was unaffected in the analyzed clone PMM2-iPSC-C3 compared with nondiseased human pluripotent stem cells (hPSCs), revealing no broader influence of the PMM2 mutation on pluripotency in cell culture. Analysis of gene expression by deep-sequencing did not show obvious differences in the transcriptome between PMM2-iPSC-C3 and nondiseased hPSCs. By multiplexed capillary gel electrophoresis coupled to laser induced fluorescence detection (xCGE-LIF) we could show that PMM2-iPSC-C3 exhibit the common hPSC N-glycosylation pattern with high-mannose-type N-glycans as the predominant species. However, phosphomannomutase activity of PMM2-iPSC-C3 was 27% compared with control hPSCs and lectin staining revealed an overall reduced protein glycosylation. In addition, quantitative assessment of N-glycosylation by xCGE-LIF showed an up to 40% reduction of high-mannose-type N-glycans in PMM2-iPSC-C3, which was in concordance to the observed reduction of the Glc3Man9GlcNAc2 lipid-linked oligosaccharide compared with control hPSCs. Thus we could model the PMM2-CDG disease phenotype of hypoglycosylation with patient derived iPSCs in vitro. Knock-down of PMM2 by shRNA in PMM2-iPSC-C3 led to a residual activity of 5% and to a further reduction of the level of N-glycosylation. Taken together we have developed human stem cell-based cell culture models with stepwise reduced levels of N-glycosylation now enabling to study the role of N-glycosylation during early human development.
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Affiliation(s)
- Christina T Thiesler
- From the ‡REBIRTH-Cluster of Excellence, Hannover Medical School, 30625 Hannover, Germany; §Institute for Cellular Chemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Samanta Cajic
- ¶Max Planck Institute for Dynamics of Complex Technical Systems, 39106 Magdeburg, Germany
| | - Dirk Hoffmann
- From the ‡REBIRTH-Cluster of Excellence, Hannover Medical School, 30625 Hannover, Germany; ‖Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
| | - Christian Thiel
- **Center for Child and Adolescent Medicine, Department Kinderheilkunde I, 69120 Heidelberg, Germany
| | - Laura van Diepen
- ‡‡Department of Human Genetics, University Medicine Greifswald and Interfaculty Institute for Genetics and Functional Genomics, Ernst-Moritz-Arndt University, 17475 Greifswald, Germany
| | - René Hennig
- ¶Max Planck Institute for Dynamics of Complex Technical Systems, 39106 Magdeburg, Germany; §§glyXera GmbH, 39120 Magdeburg, Germany
| | - Malte Sgodda
- From the ‡REBIRTH-Cluster of Excellence, Hannover Medical School, 30625 Hannover, Germany; ¶¶Translational Hepatology and Stem Cell Biology, Dept. of Gastroenterology, Hepatology, and Endocrinology, Hannover Medical School, 30625 Hannover, Germany
| | - Robert Weiβmann
- ‡‡Department of Human Genetics, University Medicine Greifswald and Interfaculty Institute for Genetics and Functional Genomics, Ernst-Moritz-Arndt University, 17475 Greifswald, Germany
| | - Udo Reichl
- ¶Max Planck Institute for Dynamics of Complex Technical Systems, 39106 Magdeburg, Germany
| | - Doris Steinemann
- From the ‡REBIRTH-Cluster of Excellence, Hannover Medical School, 30625 Hannover, Germany; ‖‖Institute of Human Genetics, Hannover Medical School, 30625 Hannover, Germany
| | - Ulf Diekmann
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Nicolas M B Huber
- From the ‡REBIRTH-Cluster of Excellence, Hannover Medical School, 30625 Hannover, Germany; §Institute for Cellular Chemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Astrid Oberbeck
- From the ‡REBIRTH-Cluster of Excellence, Hannover Medical School, 30625 Hannover, Germany; §Institute for Cellular Chemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Tobias Cantz
- From the ‡REBIRTH-Cluster of Excellence, Hannover Medical School, 30625 Hannover, Germany; ¶¶Translational Hepatology and Stem Cell Biology, Dept. of Gastroenterology, Hepatology, and Endocrinology, Hannover Medical School, 30625 Hannover, Germany
| | - Andreas W Kuss
- ‡‡Department of Human Genetics, University Medicine Greifswald and Interfaculty Institute for Genetics and Functional Genomics, Ernst-Moritz-Arndt University, 17475 Greifswald, Germany
| | - Christian Körner
- **Center for Child and Adolescent Medicine, Department Kinderheilkunde I, 69120 Heidelberg, Germany
| | - Axel Schambach
- From the ‡REBIRTH-Cluster of Excellence, Hannover Medical School, 30625 Hannover, Germany; ‖Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
| | - Erdmann Rapp
- ¶Max Planck Institute for Dynamics of Complex Technical Systems, 39106 Magdeburg, Germany; §§glyXera GmbH, 39120 Magdeburg, Germany
| | - Falk F R Buettner
- From the ‡REBIRTH-Cluster of Excellence, Hannover Medical School, 30625 Hannover, Germany; §Institute for Cellular Chemistry, Hannover Medical School, 30625 Hannover, Germany;
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18
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Youm JB. Electrophysiological properties and calcium handling of embryonic stem cell-derived cardiomyocytes. Integr Med Res 2016; 5:3-10. [PMID: 28462091 PMCID: PMC5381424 DOI: 10.1016/j.imr.2015.12.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Revised: 12/28/2015] [Accepted: 12/30/2015] [Indexed: 01/31/2023] Open
Abstract
Embryonic stem cell-derived cardiomyocytes (ESC-CMs) hold great interest in many fields of research including clinical applications such as stem cell and gene therapy for cardiac repair or regeneration. ESC-CMs are also used as a platform tool for pharmacological tests or for investigations of cardiac remodeling. ESC-CMs have many different aspects of morphology, electrophysiology, calcium handling, and bioenergetics compared with adult cardiomyocytes. They are immature in morphology, similar to sinus nodal-like in the electrophysiology, higher contribution of trans-sarcolemmal Ca2+ influx to Ca2+ handling, and higher dependence on anaerobic glycolysis. Here, I review a detailed electrophysiology and Ca2+ handling features of ESC-CMs during differentiation into adult cardiomyocytes to gain insights into how all the developmental changes are related to each other to display cardinal features of developing cardiomyocytes.
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Affiliation(s)
- Jae Boum Youm
- National Research Laboratory for Mitochondrial Signaling Laboratory, Department of Physiology, College of Medicine, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
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19
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Mesenchymal Stem Cells for Cardiac Regenerative Therapy: Optimization of Cell Differentiation Strategy. Stem Cells Int 2015; 2015:524756. [PMID: 26339251 PMCID: PMC4539177 DOI: 10.1155/2015/524756] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 02/28/2015] [Accepted: 03/11/2015] [Indexed: 01/25/2023] Open
Abstract
With the high mortality rate, coronary heart disease (CHD) has currently become a major life-threatening disease. The main pathological change of myocardial infarction (MI) is the induction of myocardial necrosis in infarction area which finally causes heart failure. Conventional treatments cannot regenerate the functional cell efficiently. Recent researches suggest that mesenchymal stem cells (MSCs) are able to differentiate into multiple lineages, including cardiomyocyte-like cells in vitro and in vivo, and they have been used for the treatment of MI to repair the injured myocardium and improve cardiac function. In this review, we will focus on the recent progress on MSCs derived cardiomyocytes for cardiac regeneration after MI.
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20
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Gap Junction-associated Na+ Influx Is Involved in the Mediation of Ca2+ Transients in Neonatal Rat Ventricular Myocytes. J Cardiovasc Pharmacol 2015; 66:41-9. [DOI: 10.1097/fjc.0000000000000241] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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21
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Mehta S, Aye-Han NN, Ganesan A, Oldach L, Gorshkov K, Zhang J. Calmodulin-controlled spatial decoding of oscillatory Ca2+ signals by calcineurin. eLife 2014; 3:e03765. [PMID: 25056880 PMCID: PMC4141273 DOI: 10.7554/elife.03765] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Calcineurin is responsible for mediating a wide variety of cellular processes in response to dynamic calcium (Ca(2+)) signals, yet the precise mechanisms involved in the spatiotemporal control of calcineurin signaling are poorly understood. Here, we use genetically encoded fluorescent biosensors to directly probe the role of cytosolic Ca(2+) oscillations in modulating calcineurin activity dynamics in insulin-secreting MIN6 β-cells. We show that Ca(2+) oscillations induce distinct temporal patterns of calcineurin activity in the cytosol and plasma membrane vs at the ER and mitochondria in these cells. Furthermore, we found that these differential calcineurin activity patterns are determined by variations in the subcellular distribution of calmodulin (CaM), indicating that CaM plays an active role in shaping both the spatial and temporal aspects of calcineurin signaling. Together, our findings provide new insights into the mechanisms by which oscillatory signals are decoded to generate specific functional outputs within different cellular compartments.
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Affiliation(s)
- Sohum Mehta
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, United States
| | - Nwe-Nwe Aye-Han
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, United States
| | - Ambhighainath Ganesan
- Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, United States
| | - Laurel Oldach
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, United States
| | - Kirill Gorshkov
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, United States
| | - Jin Zhang
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, United States The Solomon H. Snyder Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, United States Department of Oncology, The Johns Hopkins University School of Medicine, Baltimore, United States
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22
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Qing Q, Jiang Z, Xu L, Gao R, Mai L, Lieber CM. Free-standing kinked nanowire transistor probes for targeted intracellular recording in three dimensions. NATURE NANOTECHNOLOGY 2014; 9:142-7. [PMID: 24336402 PMCID: PMC3946362 DOI: 10.1038/nnano.2013.273] [Citation(s) in RCA: 148] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 11/13/2013] [Indexed: 05/21/2023]
Abstract
Recording intracellular (IC) bioelectrical signals is central to understanding the fundamental behaviour of cells and cell networks in, for example, neural and cardiac systems. The standard tool for IC recording, the patch-clamp micropipette is applied widely, yet remains limited in terms of reducing the tip size, the ability to reuse the pipette and ion exchange with the cytoplasm. Recent efforts have been directed towards developing new chip-based tools, including micro-to-nanoscale metal pillars, transistor-based kinked nanowires and nanotube devices. These nanoscale tools are interesting with respect to chip-based multiplexing, but, so far, preclude targeted recording from specific cell regions and/or subcellular structures. Here we overcome this limitation in a general manner by fabricating free-standing probes in which a kinked silicon nanowire with an encoded field-effect transistor detector serves as the tip end. These probes can be manipulated in three dimensions within a standard microscope to target specific cells or cell regions, and record stable full-amplitude IC action potentials from different targeted cells without the need to clean or change the tip. Simultaneous measurements from the same cell made with free-standing nanowire and patch-clamp probes show that the same action potential amplitude and temporal properties are recorded without corrections to the raw nanowire signal. In addition, we demonstrate real-time monitoring of changes in the action potential as different ion-channel blockers are applied to cells, and multiplexed recording from cells by independent manipulation of two free-standing nanowire probes.
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Affiliation(s)
- Quan Qing
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, 02138, USA
| | - Zhe Jiang
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, 02138, USA
| | - Lin Xu
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, 02138, USA
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, WUT-Harvard Joint Nano Key Laboratory, Wuhan University of Technology, Wuhan 430070, China
| | - Ruixuan Gao
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, 02138, USA
| | - Liqiang Mai
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, WUT-Harvard Joint Nano Key Laboratory, Wuhan University of Technology, Wuhan 430070, China
| | - Charles M. Lieber
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, 02138, USA
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, WUT-Harvard Joint Nano Key Laboratory, Wuhan University of Technology, Wuhan 430070, China
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, 02138, USA
- To whom correspondence should be addressed.
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23
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Karppinen S, Rapila R, Mäkikallio K, Hänninen SL, Rysä J, Vuolteenaho O, Tavi P. Endothelin-1 signalling controls early embryonic heart rate in vitro and in vivo. Acta Physiol (Oxf) 2014; 210:369-80. [PMID: 24325624 DOI: 10.1111/apha.12194] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 04/10/2013] [Accepted: 01/11/2013] [Indexed: 12/13/2022]
Abstract
AIM Spontaneous activity of embryonic cardiomyocytes originates from sarcoplasmic reticulum (SR) Ca(2+) release during early cardiogenesis. However, the regulation of heart rate during embryonic development is still not clear. The aim of this study was to determine how endothelin-1 (ET-1) affects the heart rate of embryonic mice, as well as the pathway through which it exerts its effects. METHODS The effects of ET-1 and ET-1 receptor inhibition on cardiac contraction were studied using confocal Ca(2+) imaging of isolated mouse embryonic ventricular cardiomyocytes and ultrasonographic examination of embryonic cardiac contractions in utero. In addition, the amount of ET-1 peptide and ET receptor a (ETa) and b (ETb) mRNA levels were measured during different stages of development of the cardiac muscle. RESULTS High ET-1 concentration and expression of both ETa and ETb receptors was observed in early cardiac tissue. ET-1 was found to increase the frequency of spontaneous Ca(2+) oscillations in E10.5 embryonic cardiomyocytes in vitro. Non-specific inhibition of ET receptors with tezosentan caused arrhythmia and bradycardia in isolated embryonic cardiomyocytes and in whole embryonic hearts both in vitro (E10.5) and in utero (E12.5). ET-1-mediated stimulation of early heart rate was found to occur via ETb receptors and subsequent inositol trisphosphate receptor activation and increased SR Ca(2+) leak. CONCLUSION Endothelin-1 is required to maintain a sufficient heart rate, as well as to prevent arrhythmia during early development of the mouse heart. This is achieved through ETb receptor, which stimulates Ca(2+) leak through IP3 receptors.
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Affiliation(s)
- S. Karppinen
- Department of Biotechnology and Molecular Medicine; A.I. Virtanen Institute for Molecular Sciences; University of Eastern Finland; Kuopio Finland
| | - R. Rapila
- Department of Biotechnology and Molecular Medicine; A.I. Virtanen Institute for Molecular Sciences; University of Eastern Finland; Kuopio Finland
| | - K. Mäkikallio
- Department of Obstetrics and Gynecology; University of Oulu; Oulu Finland
| | - S. L. Hänninen
- Department of Physiology; Institute of Biomedicine; University of Oulu; Oulu Finland
| | - J. Rysä
- Department of Pharmacology and Toxicology; Institute of Biomedicine; University of Oulu; Oulu Finland
| | - O. Vuolteenaho
- Department of Physiology; Institute of Biomedicine; University of Oulu; Oulu Finland
| | - P. Tavi
- Department of Biotechnology and Molecular Medicine; A.I. Virtanen Institute for Molecular Sciences; University of Eastern Finland; Kuopio Finland
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24
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Kapoor N, Maxwell JT, Mignery GA, Will D, Blatter LA, Banach K. Spatially defined InsP3-mediated signaling in embryonic stem cell-derived cardiomyocytes. PLoS One 2014; 9:e83715. [PMID: 24409283 PMCID: PMC3883750 DOI: 10.1371/journal.pone.0083715] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 11/06/2013] [Indexed: 11/19/2022] Open
Abstract
The functional role of inositol 1,4,5-trisphosphate (InsP3) signaling in cardiomyocytes is not entirely understood but it was linked to an increased propensity for triggered activity. The aim of this study was to determine how InsP3 receptors can translate Ca(2+) release into a depolarization of the plasma membrane and consequently arrhythmic activity. We used embryonic stem cell-derived cardiomyocytes (ESdCs) as a model system since their spontaneous electrical activity depends on InsP3-mediated Ca(2+) release. [InsP3]i was monitored with the FRET-based InsP3-biosensor FIRE-1 (Fluorescent InsP3 Responsive Element) and heterogeneity in sub-cellular [InsP3]i was achieved by targeted expression of FIRE-1 in the nucleus (FIRE-1nuc) or expression of InsP3 5-phosphatase (m43) localized to the plasma membrane. Spontaneous activity of ESdCs was monitored simultaneously as cytosolic Ca(2+) transients (Fluo-4/AM) and action potentials (current clamp). During diastole, the diastolic depolarization was paralleled by an increase of [Ca(2+)]i and spontaneous activity was modulated by [InsP3]i. A 3.7% and 1.7% increase of FIRE-1 FRET ratio and 3.0 and 1.5 fold increase in beating frequency was recorded upon stimulation with endothelin-1 (ET-1, 100 nmol/L) or phenylephrine (PE, 10 µmol/L), respectively. Buffering of InsP3 by FIRE-1nuc had no effect on the basal frequency while attenuation of InsP3 signaling throughout the cell (FIRE-1), or at the plasma membrane (m43) resulted in a 53.7% and 54.0% decrease in beating frequency. In m43 expressing cells the response to ET-1 was completely suppressed. Ca(2+) released from InsP3Rs is more effective than Ca(2+) released from RyRs to enhance INCX. The results support the hypothesis that in ESdCs InsP3Rs form a functional signaling domain with NCX that translates Ca(2+) release efficiently into a depolarization of the membrane potential.
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Affiliation(s)
- Nidhi Kapoor
- Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California, United States of America
| | - Joshua T. Maxwell
- Department of Molecular Biophysics and Physiology, Rush University Medical Center, Chicago, Illinois, United States of America
| | - Gregory A. Mignery
- Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois, United States of America
| | - David Will
- Center for Cardiovascular Research, Dept. of Medicine, Section of Cardiology, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Lothar A. Blatter
- Department of Molecular Biophysics and Physiology, Rush University Medical Center, Chicago, Illinois, United States of America
| | - Kathrin Banach
- Center for Cardiovascular Research, Dept. of Medicine, Section of Cardiology, University of Illinois at Chicago, Chicago, Illinois, United States of America
- * E-mail:
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Nilsson MF, Ritchie H, Webster WS. The effect on rat embryonic heart rate of Na+, K+, and Ca2+ channel blockers, and the human teratogen phenytoin, changes with gestational age. ACTA ACUST UNITED AC 2013; 98:416-27. [PMID: 24323366 DOI: 10.1002/bdrb.21084] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 10/28/2013] [Accepted: 10/28/2013] [Indexed: 11/09/2022]
Abstract
In this study, we compared the effects of four ion channel blockers on rat embryonic heart function during the organogenic period from gestational day (GD) 10 to 15, to determine the changes in dependence on ion channels during rat cardiac development. Rat embryos in culture were exposed to either the human ether-á-go-go-related gene potassium channel blocker, dofetilide (400 nM); the sodium channel blocker, lidocaine (250 μM); the L-type calcium channel blocker, nifedipine (1.8 μM); or the multichannel blocker, phenytoin (200 μM). Lidocaine slowed the heart rate (HR) with the effect becoming more severe with increasing GD. Dofetilide slowed the embryonic HR and caused arrhythmias with the most severe effect on GD 11 to 13. Nifedipine primarily caused a negative inotropic effect except on GD 10 when it stopped the heart in most embryos. Phenytoin stopped the heart of most GD 10 to 12 embryos while on GD 13 to 15 phenytoin slowed the heart. The results demonstrate that as the rat heart develops during the organogenic period its functional dependence on ion channels changes markedly. These changes are important for understanding drug effects on the embryo during pregnancy and the methodology used provides a simple procedure for assessing drug effects on the developing heart.
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Affiliation(s)
- Mats F Nilsson
- Drug Safety and Toxicology, Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
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Wang P, Tang M, Gao L, Luo H, Wang G, Ma X, Duan Y. Roles of I(f) and intracellular Ca2+ release in spontaneous activity of ventricular cardiomyocytes during murine embryonic development. J Cell Biochem 2013; 114:1852-62. [PMID: 23463619 DOI: 10.1002/jcb.24527] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Accepted: 02/21/2013] [Indexed: 01/01/2023]
Abstract
In recent years, the contribution of I(f), an important pacemaker current, and intracellular Ca(2+) release (ICR) from sarcoplasmic reticulum to pacemaking and arrhythmia has been intensively studied. However, their functional roles in embryonic heart remain uncertain. Using patch clamp, Ca(2+) imaging, and RT-PCR, we found that I(f) regulated the firing rate in early and late stage embryonic ventricular cells, as ivabradine (30 µM), a specific blocker of I(f), slowed down action potential (AP) frequency. This inhibitory effect was even stronger in late stage cells, though I(f) was down-regulated. In contrast to I(f), ICR was found to be indispensable for the occurrence of APs in ventricular cells of different stages, because abolishment of ICR with ryanodine and 2-aminoethoxydiphenyl borate (2-APB), specific blockers of ryanodine receptors (RyRs) and inositol trisphosphate receptors (IP3Rs), completely abolished APs. In addition, we noticed that RyR- and IP3R-mediated ICR coexisted in early-stage ventricular cells and RyRs functionally dominated. While at late stage RyRs, but not IP3Rs, mediated ICR. In both early and late stage ventricular cells, Na-Ca exchanger current (I(Na/Ca)) mediated ICR-triggered depolarization of membrane potential and resulted in the initiation of APs. We also observed that different from I(f), which presented as the substantial component of the earlier diastolic depolarization current, application of ryanodine, and/or 2-APB slowed the late phase of diastolic depolarization. Thus, we conclude that in murine embryonic ventricular cells I(f) regulates firing rate, while RyRs and IP3Rs (early stage) or RyRs (late stage)-mediated ICR determines the occurrence of APs.
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Affiliation(s)
- Peng Wang
- Department of Physiology, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
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27
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Bekhite MM, Figulla HR, Sauer H, Wartenberg M. Static magnetic fields increase cardiomyocyte differentiation of Flk-1+ cells derived from mouse embryonic stem cells via Ca2+ influx and ROS production. Int J Cardiol 2013; 167:798-808. [DOI: 10.1016/j.ijcard.2012.02.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Revised: 01/16/2012] [Accepted: 02/26/2012] [Indexed: 11/16/2022]
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Nguemo F, Fleischmann BK, Gupta MK, Šarić T, Malan D, Liang H, Pfannkuche K, Bloch W, Schunkert H, Hescheler J, Reppel M. The L-type Ca2+ channels blocker nifedipine represses mesodermal fate determination in murine embryonic stem cells. PLoS One 2013; 8:e53407. [PMID: 23320083 PMCID: PMC3539992 DOI: 10.1371/journal.pone.0053407] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2012] [Accepted: 11/28/2012] [Indexed: 01/20/2023] Open
Abstract
Dihydropyridines (DHP), which nifedipine is a member of, preferentially block Ca(2+) channels of different cell types. Moreover, influx of Ca(2+) through L-type Ca(2+) channels (LTCCs) activates Ca(2+) signaling pathways, which in turn contribute to numerous cellular processes. Although LTCCs are expressed in undifferentiated cells, very little is known about its contributions to the transcriptional regulation of mesodermal and cardiac genes. This study aimed to examine the contribution of LTCCs and the effect of nifedipine on the commitment of pluripotent stem cells toward the cardiac lineage in vitro. The murine embryonic stem (ES, cell line D3) and induced pluripotent stem (iPS, cell clone 09) cells were differentiated into enhanced green fluorescence protein (EGFP) expressing spontaneously beating cardiomyocytes (CMs). Early treatment of differentiating cells with 10 µM nifedipine led to a significant inhibition of the cardiac mesoderm formation and cardiac lineage commitment as revealed by gene regulation analysis. This was accompanied by the inhibition of spontaneously occurring Ca(2+) transient and reduction of LTCCs current density (I(CaL)) of differentiated CMs. In addition, nifedipine treatment instigated a pronounced delay of the spontaneous beating embryoid body (EB) and led to a poor surface localization of L-type Ca(2+) channel α(1C) (Ca(V)1.2) subunits. Contrary late incubation of pluripotent stem cells with nifedipine was without any impact on the differentiation process and did not affect the derived CMs function. Our data indicate that nifedipine blocks the determined path of pluripotent stem cells to cardiomyogenesis by inhibition of mesodermal commitment at early stages of differentiation, thus the proper upkeep Ca(2+) concentration and pathways are essentially required for cardiac gene expression, differentiation and function.
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Affiliation(s)
- Filomain Nguemo
- Institute of Neurophysiology, University of Cologne, Cologne, Germany
| | - Bernd K. Fleischmann
- Institute of Physiology I, Life and Brain Center, University of Bonn, Bonn, Germany
| | - Manoj K. Gupta
- Institute of Neurophysiology, University of Cologne, Cologne, Germany
| | - Tomo Šarić
- Institute of Neurophysiology, University of Cologne, Cologne, Germany
| | - Daniela Malan
- Institute of Physiology I, Life and Brain Center, University of Bonn, Bonn, Germany
| | - Huamin Liang
- Department of Physiology, Huazhong University of Science and Technology, Tongji Medical College, Wuhan, China
| | - Kurt Pfannkuche
- Institute of Neurophysiology, University of Cologne, Cologne, Germany
| | - Wilhelm Bloch
- Department of Molecular and Cellular Sport Medicine, German Sport University, Cologne, Germany
| | | | - Jürgen Hescheler
- Institute of Neurophysiology, University of Cologne, Cologne, Germany
| | - Michael Reppel
- Institute of Neurophysiology, University of Cologne, Cologne, Germany
- Department of Cardiology, Medical University of Lübeck, Lübeck, Germany
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Nguyen C, Lieberherr M, Bordat C, Velard F, Côme D, Lioté F, Ea HK. Intracellular calcium oscillations in articular chondrocytes induced by basic calcium phosphate crystals lead to cartilage degradation. Osteoarthritis Cartilage 2012; 20:1399-408. [PMID: 22885567 DOI: 10.1016/j.joca.2012.07.017] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Revised: 07/18/2012] [Accepted: 07/25/2012] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Basic calcium phosphate (BCP) crystals, including octacalcium phosphate (OCP), carbonated-apatite (CA) and hydroxyapatite (HA) crystals are associated with destructive forms of osteoarthritis. Mechanisms of BCP-induced cartilage breakdown remain incompletely understood. We assessed the ability of BCP to induce changes in intracellular calcium (iCa(2+)) content and oscillations and the role of iCa(2+) in BCP-induced cartilage degradation. METHODS Bovine articular chondrocytes (BACs) and bovine cartilage explants (BCEs) were stimulated with BCP or monosodium urate (MSU) crystals. iCa(2+) levels were determined by spectrofluorimetry and oscillations by confocal microscopy. mRNA expression of matrix metalloproteinase 3 (MMP-3), a disintegrin and metalloprotease with thrombospondin-like motifs 4 (ADAMTS-4) and ADAMTS-5 was assessed by quantitative real-time PCR. Glycosaminoglycan (GAG) release was measured in the supernatants of BCE cultures. RESULTS All three BCP crystals significantly increased iCa(2+) content. OCP also induced iCa(2+) oscillations. Rate of BACs displaying iCa(2+) oscillations increased over time, with a peak after 20 min of stimulation. OCP-induced iCa(2+) oscillations involved both extracellular Ca(2+) (eCa(2+)) influx and iCa(2+) stores. Indeed, OCP-induced iCa(2+) oscillations decreased rapidly in Ca(2+)-free medium. Both voltage- and non-voltage-dependent Ca(2+) channels were involved in eCa(2+) influx. BCP crystal-induced variation in iCa(2+) content was associated with BCP crystal-induced cartilage matrix degradation. However, iCa²(+) was not associated with OCP crystal-induced mRNA expression of MMP-3, ADAMTS-4 or ADAMTS-5. CONCLUSION BCP crystals can induce variation in iCa(2+) content and oscillations in articular chondrocytes. Furthermore, BCP crystal-induced changes in iCa(2+) content play a pivotal role in BCP catabolic effects on articular cartilage.
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Affiliation(s)
- C Nguyen
- Univ Paris Diderot, Sorbonne Paris Cité, INSERM, UMR-S 606, F-75205 Paris, France
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Malan D, Fleischmann BK. Functional expression and modulation of the L-type Ca2+ current in embryonic heart cells. Pediatr Cardiol 2012; 33:907-15. [PMID: 22639002 DOI: 10.1007/s00246-012-0360-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Accepted: 04/30/2012] [Indexed: 11/28/2022]
Abstract
Voltage-dependent L-type Ca2+ channels (VDCCs) are critically involved in excitation contraction coupling and regulation of the force of contraction. An important mechanism contributing to the adaptation of heart function is modulation of the L-type Ca2+ current (I(Ca-L)) by hormones of the autonomous nervous system. The signaling pathways underlying this regulation in the adult heart are well understood. However, VDCC expression and its regulation in the embryonic heart are less understood. This report therefore provides a short overview of the current knowledge on this topic using embryonic stem cells and the mouse as model systems.
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Affiliation(s)
- Daniela Malan
- Institute of Physiology I, Life and Brain Center, University of Bonn, Sigmund-Freud-Strasse 25, 53105, Bonn, Germany.
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Kurata Y, Hisatome I, Shibamoto T. Roles of sarcoplasmic reticulum Ca2+ cycling and Na+/Ca2+ exchanger in sinoatrial node pacemaking: Insights from bifurcation analysis of mathematical models. Am J Physiol Heart Circ Physiol 2012; 302:H2285-300. [DOI: 10.1152/ajpheart.00221.2011] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
To elucidate the roles of sarcoplasmic reticulum (SR) Ca2+ cycling and Na+/Ca2+ exchanger (NCX) in sinoatrial node (SAN) pacemaking, we have applied stability and bifurcation analyses to a coupled-clock system model developed by Maltsev and Lakatta ( Am J Physiol Heart Circ Physiol 296: H594-H615, 2009). Equilibrium point (EP) at which the system is stationary (i.e., the oscillatory system fails to function), periodic orbit (limit cycle), and their stability were determined as functions of model parameters. The stability analysis to detect bifurcation points confirmed crucial importance of SR Ca2+ pumping rate constant ( Pup), NCX density ( kNCX), and L-type Ca2+ channel conductance for the system function reported in previous parameter-dependent numerical simulations. We showed, however, that the model cell does not exhibit self-sustained automaticity of SR Ca2+ release at any clamped voltage and therefore needs further tuning to reproduce oscillatory local Ca2+ release and net membrane current reported experimentally at −10 mV. Our further extended bifurcation analyses revealed important novel features of the pacemaker system that go beyond prior numerical simulations in relation to the roles of SR Ca2+ cycling and NCX in SAN pacemaking. Specifically, we found that 1) NCX contributes to EP instability and enhancement of robustness in the full system during normal spontaneous action potential firings, while stabilizing EPs to prevent sustained Ca2+ oscillations under voltage clamping; 2) SR requires relatively large kNCX and subsarcolemmal Ca2+ diffusion barrier (i.e., subspace) to contribute to EP destabilization and enhancement of robustness; and 3) decrementing Pup or kNCX decreased the full system robustness against hyperpolarizing loads because EP stabilization and cessation of pacemaking were observed at the lower critical amplitude of hyperpolarizing bias currents, suggesting that SR Ca2+ cycling contributes to enhancement of the full system robustness by modulating NCX currents and promoting EP destabilization.
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Affiliation(s)
- Yasutaka Kurata
- Department of Physiology, Kanazawa Medical University, Ishikawa; and
| | - Ichiro Hisatome
- Division of Regenerative Medicine and Therapeutics, Tottori University Graduate School of Medical Science, Yonago, Japan
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Ababneh D, Ritchie H, Webster WS. Antidepressants Cause Bradycardia and Heart Block in GD 13 Rat Embryos In Vitro. ACTA ACUST UNITED AC 2012; 95:184-93. [DOI: 10.1002/bdrb.21003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Deena Ababneh
- Department of Anatomy and Histology; Sydney Medical School; University of Sydney; Sydney; Australia
| | - Helen Ritchie
- Discipline of Biomedical Sciences,; Sydney Medical School; University of Sydney; Sydney; Australia
| | - William S. Webster
- Department of Anatomy and Histology; Sydney Medical School; University of Sydney; Sydney; Australia
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Pillekamp F, Haustein M, Khalil M, Emmelheinz M, Nazzal R, Adelmann R, Nguemo F, Rubenchyk O, Pfannkuche K, Matzkies M, Reppel M, Bloch W, Brockmeier K, Hescheler J. Contractile properties of early human embryonic stem cell-derived cardiomyocytes: beta-adrenergic stimulation induces positive chronotropy and lusitropy but not inotropy. Stem Cells Dev 2012; 21:2111-21. [PMID: 22268955 DOI: 10.1089/scd.2011.0312] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Human embryonic stem cell-derived cardiomyocytes (hESC-CMs) provide the unique opportunity to study the very early development of the human heart. The aim of this study was to investigate the effect of calcium and beta-adrenergic stimulation on the contractile properties of early hESC-CMs. Beating clusters containing hESC-CMs were co-cultured in vitro with noncontractile slices of neonatal murine ventricles. After 5-7 days, when beating clusters had integrated morphologically into the damaged tissue, isometric force measurements were performed during spontaneous beating as well as during electrical field stimulation. Spontaneous beating stopped when extracellular calcium ([Ca²⁺](ec)) was removed or after administration of the Ca²⁺ channel blocker nifedipine. During field stimulation at a constant rate, the developed force increased with incremental concentrations of [Ca²⁺](ec). During spontaneous beating, rising [Ca²⁺](ec) increased beating rate and developed force up to a [Ca²⁺](ec) of 2.5 mM. When [Ca²⁺](ec) was increased further, spontaneous beating rate decreased, whereas the developed force continued to increase. The beta-adrenergic agonist isoproterenol induced a dose-dependent increase of the frequency of spontaneous beating; however, it did not significantly change the developed force during spontaneous contractions or during electrical stimulation at a constant rate. Force developed by early hESC-CMs depends on [Ca²⁺](ec) and on the L-type Ca²⁺ channel. The lack of an inotropic reaction despite a pronounced chronotropic response after beta-adrenergic stimulation most likely indicates immaturity of the sarcoplasmic reticulum. For cell-replacement strategies, further maturation of cardiac cells has to be achieved either in vitro before or in vivo after transplantation.
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Affiliation(s)
- Frank Pillekamp
- Pediatric Cardiology, Heinrich-Heine-University of Duesseldorf, Duesseldorf, Germany
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Nie L, Tang M, Zeng Y, Jiang H, Shi H, Luo H, Hu X, Gao L, Xi J, Liu A, Reppel M, Hescheler J, Liang H. Properties and functions of KATP during mouse perinatal development. Biochem Biophys Res Commun 2012; 418:74-80. [PMID: 22252295 DOI: 10.1016/j.bbrc.2011.12.133] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 12/26/2011] [Indexed: 10/14/2022]
Abstract
BACKGROUND Prevailing data suggest that ATP-sensitive potassium channels (K(ATP)) contribute to a surprising resistance to hypoxia in mammalian embryos, thus we aimed to characterize the developmental changes of K(ATP) channels in murine fetal ventricular cardiomyocytes. METHODS Patch clamp was applied to investigate the functions of K(ATP). RT-PCR, Western blot were used to further characterize the molecular properties of K(ATP) channels. RESULTS Similar K(ATP) current density was detected in ventricular cardiomyocytes of late development stage (LDS) and early development stage (EDS). Molecular-biological study revealed the upregulation of Kir6.1/SUR2A in membrane and Kir6.2 remained constant during development. Kir6.1, Kir6.2, and SUR1 were detectable in the mitochondria without marked difference between EDS and LDS. Acute hypoxia-ischemia led to cessation of APs in 62.5% of tested EDS cells and no APs cessation was observed in LDS cells. SarcK(ATP) blocker glibenclamide rescued 47% of EDS cells but converted 42.8% of LDS cells to APs cessations under hypoxia-ischemic condition. MitoK(ATP) blocker 5-HD did not significantly influence the response to acute hypoxia-ischemia at either EDS or LDS. In summary, sarcK(ATP) played distinct functional roles under acute hypoxia-ischemic condition in EDS and LDS fetal ventricular cardiomyocytes, with developmental changes in sarcK(ATP) subunits. MitoK(ATP) were not significantly involved in the response of fetal cardiomyocytes to acute hypoxia-ischemia and no developmental changes of K(ATP) subunits were found in mitochondria.
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Affiliation(s)
- Li Nie
- Department of Physiology, Tongji Medical College, Huazhong University of Science and Technology, Hangkong Road 13, Wuhan 430030, China
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Abtahi S, Sadraei H, Nematollahi M, Karbalaie K, Karamali F, Salamian A, Baharvand H, Nasr-Esfahani MH. Functional expression of potassium channels in cardiomyocytes derived from embryonic stem cells. Res Pharm Sci 2012. [PMID: 23181074 PMCID: PMC3500552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Royan B(1) stem cell can be differentiated to specialized cell types including cardiomyocytes. This developmental change is accompanied with expression of various K(+) channel types. The aim of this study was to detect functional expression of K(+) currents from stem cell stage and one week and two weeks after differentiation into cardiomyocyte. Mouse stem cell derived cardiomyocytes (ES-cardiomyocytes) were isolated to single cell suspension for K(+) current recording using whole cell patch-clamp technique. The predominant depolarizing current in ES-cardiomyocytes was a tetraethylammonium (TEA) (10 mM) sensitive current which was partially blocked by nifedipine (1 μM) and attenuated by increasing concentration of EGTA (10 mM) in the pipette solution. Pharmacology and electrophysiological properties of this oscillatory sustained current very well matched with characteristics of Ca(2+) activated K(+) current. In addition there was another kind of sustained outward K(+) current which was resistance to TEA but was inhibited by 3,4-diaminopyridine. The characteristic features of this current indicate that this current was due to activation of delayed rectifier K(+) channels. RT-PCR study also confirmed expression of these two types of K(+) channels in ES-cardiomyocytes. Therefore, present study shows functional expression of two types of K(+) ionic current in ES-cardiomyocytes.
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Affiliation(s)
- S.R. Abtahi
- Department of Pharmacology and Toxicology and Isfahan Pharmaceutical Sciences Research Center, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, I.R.Iran,Department of Cell and Molecular Biology, Royan Institute for Animal Biotechnology, ACECR, Isfahan, I.R.Iran
| | - H. Sadraei
- Department of Pharmacology and Toxicology and Isfahan Pharmaceutical Sciences Research Center, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, I.R.Iran,Corresponding authors:
Dr. H. Sadraei, , Tel. 0098 311 7922608, Fax. 0098 311 6680011
Dr. M.H. Nasr-Esfahani, , Tel. 0098 311 2612900-3, Fax. 0098 311 2605525
| | - M. Nematollahi
- Department of Cell and Molecular Biology, Royan Institute for Animal Biotechnology, ACECR, Isfahan, I.R.Iran
| | - K. Karbalaie
- Department of Cell and Molecular Biology, Royan Institute for Animal Biotechnology, ACECR, Isfahan, I.R.Iran
| | - F. Karamali
- Department of Cell and Molecular Biology, Royan Institute for Animal Biotechnology, ACECR, Isfahan, I.R.Iran
| | - A. Salamian
- Department of Cell and Molecular Biology, Royan Institute for Animal Biotechnology, ACECR, Isfahan, I.R.Iran
| | - H. Baharvand
- Department of Stem Cells and Developmental Biology, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, I.R.Iran,Department of Developmental Biology, University of Science and Culture, ACECR, Tehran, I.R.Iran
| | - M. H. Nasr-Esfahani
- Department of Cell and Molecular Biology, Royan Institute for Animal Biotechnology, ACECR, Isfahan, I.R.Iran,Corresponding authors:
Dr. H. Sadraei, , Tel. 0098 311 7922608, Fax. 0098 311 6680011
Dr. M.H. Nasr-Esfahani, , Tel. 0098 311 2612900-3, Fax. 0098 311 2605525
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Jonsson MKB, Wang QD, Becker B. Impedance-based detection of beating rhythm and proarrhythmic effects of compounds on stem cell-derived cardiomyocytes. Assay Drug Dev Technol 2011; 9:589-99. [PMID: 22085047 DOI: 10.1089/adt.2011.0396] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The xCELLigence real time cell analyzer Cardio system offers a new system for real-time cell analysis that measures impedance-based signals in a label-free noninvasive manner. The aim of this study was to test whether impedance readings are a useful tool to detect compound effects on beating frequency (beats per minute, bpm) and arrhythmias of human induced pluripotent stem cell- and a mouse embryonic stem cell-derived cardiomyocyte line (hiPSC-CM and mESC-CM, respectively). Baseline values for control wells were 45±3 and 179±6 bpm, respectively (n=6). Correspondingly, isoproterenol increased beating frequency by 77% and 71%, whereas carbachol decreased frequency by 11% and 100% (stopped in 5/6 mESC-CM wells). E-4031 decreased beating rate and caused arrhythmias in both cell types, however, more pronounced in the human iPSC-CMs. Amlodipine inhibited contractions in both models, and T-type calcium channel block strongly reduced beating rate and eventually stopped beating in mESC-CM but caused a smaller effect in hiPSC-CM. The results of this initial study show that, under the right conditions, the beating frequency of a monolayer of cells can be stably recorded over several days. Additionally, the system detects changes in beating frequency and amplitude caused by added reference compounds. This assay system has the potential to enable medium-throughput screening, but for implementation into routine daily work, extended validation, testing of additional batches of cardiomyocytes, and further assay optimization (e.g., frequency of media exchange, growth matrix, seeding density, age of cells after plating, and temperature control) will be needed.
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Affiliation(s)
- Malin K B Jonsson
- Department of Medical Physiology, Heart & Lungs Division, University Medical Center Utrecht, Utrecht, The Netherlands
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Feliciano DF, Bassani RA, Oliveira PX, Bassani JWM. Pacemaker activity in the insect (T. molitor) heart: role of the sarcoplasmic reticulum. Am J Physiol Regul Integr Comp Physiol 2011; 301:R1838-45. [PMID: 21917905 DOI: 10.1152/ajpregu.00089.2011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The electrophysiological properties of the myogenic cardiac cells of insects have been analyzed, but the mechanisms that regulate the pacemaker activity have not been elucidated yet. In mammalian pacemaker cells, different types of membrane ion channels seem to be sequentially activated, perhaps in a cooperative fashion with the current generated by Ca(2+) extrusion mediated by the electrogenic Na(+)/Ca(2+) exchanger, which is sustained by the diastolic sarcoplasmic reticulum (SR) Ca(2+) release. The objective of the present work was to investigate the role of the SR function on the basal beating rate (BR), and BR modulation by extracellular Ca(2+) concentration ([Ca(2+)](o)) and neurotransmitters in the in situ dorsal vessel (heart) of the mealworm beetle Tenebrio molitor. The main observations were as follows: 1) basal BR was reduced by 50% by inhibition of SR function, but not affected by perfusion with CsCl or ZD7288; 2) spontaneous activity was abolished by Cd(2+); 3) a robust positive chronotropic response could be elicited to serotonin (5-HT), but not to norepinephrine or carbamylcholine; 4) SR inhibition abolished the sustained chronotropic stimulation by [Ca(2+)](o) elevation and by 5-HT, while the latter was unaffected by CsCl. It is concluded that, in T. molitor heart, BR is markedly, but not exclusively, dependent on the SR function, and that BR control and modulation by both [Ca(2+)](o) and 5-HT requires a functional SR.
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Affiliation(s)
- Danielle F Feliciano
- Center for Biomedical Engineering, School of Electrical and Computer Engineering, University of Campinas, Campinas, Brazil
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Itzhaki I, Rapoport S, Huber I, Mizrahi I, Zwi-Dantsis L, Arbel G, Schiller J, Gepstein L. Calcium handling in human induced pluripotent stem cell derived cardiomyocytes. PLoS One 2011; 6:e18037. [PMID: 21483779 PMCID: PMC3069979 DOI: 10.1371/journal.pone.0018037] [Citation(s) in RCA: 145] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Accepted: 02/23/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The ability to establish human induced pluripotent stem cells (hiPSCs) by reprogramming of adult fibroblasts and to coax their differentiation into cardiomyocytes opens unique opportunities for cardiovascular regenerative and personalized medicine. In the current study, we investigated the Ca(2+)-handling properties of hiPSCs derived-cardiomyocytes (hiPSC-CMs). METHODOLOGY/PRINCIPAL FINDINGS RT-PCR and immunocytochemistry experiments identified the expression of key Ca(2+)-handling proteins. Detailed laser confocal Ca(2+) imaging demonstrated spontaneous whole-cell [Ca(2+)](i) transients. These transients required Ca(2+) influx via L-type Ca(2+) channels, as demonstrated by their elimination in the absence of extracellular Ca(2+) or by administration of the L-type Ca(2+) channel blocker nifedipine. The presence of a functional ryanodine receptor (RyR)-mediated sarcoplasmic reticulum (SR) Ca(2+) store, contributing to [Ca(2+)](i) transients, was established by application of caffeine (triggering a rapid increase in cytosolic Ca(2+)) and ryanodine (decreasing [Ca(2+)](i)). Similarly, the importance of Ca(2+) reuptake into the SR via the SR Ca(2+) ATPase (SERCA) pump was demonstrated by the inhibiting effect of its blocker (thapsigargin), which led to [Ca(2+)](i) transients elimination. Finally, the presence of an IP3-releasable Ca(2+) pool in hiPSC-CMs and its contribution to whole-cell [Ca(2+)](i) transients was demonstrated by the inhibitory effects induced by the IP3-receptor blocker 2-Aminoethoxydiphenyl borate (2-APB) and the phospholipase C inhibitor U73122. CONCLUSIONS/SIGNIFICANCE Our study establishes the presence of a functional, SERCA-sequestering, RyR-mediated SR Ca(2+) store in hiPSC-CMs. Furthermore, it demonstrates the dependency of whole-cell [Ca(2+)](i) transients in hiPSC-CMs on both sarcolemmal Ca(2+) entry via L-type Ca(2+) channels and intracellular store Ca(2+) release.
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MESH Headings
- Animals
- Biological Transport
- Calcium/metabolism
- Calcium Channels, L-Type/genetics
- Calcium Channels, L-Type/metabolism
- Cell Differentiation
- Cell Line
- Gene Expression Regulation
- Humans
- Induced Pluripotent Stem Cells/cytology
- Inositol 1,4,5-Trisphosphate/metabolism
- Inositol 1,4,5-Trisphosphate Receptors/genetics
- Inositol 1,4,5-Trisphosphate Receptors/metabolism
- Intracellular Space/metabolism
- Mice
- Myocytes, Cardiac/cytology
- Myocytes, Cardiac/enzymology
- Myocytes, Cardiac/metabolism
- Ryanodine Receptor Calcium Release Channel/genetics
- Ryanodine Receptor Calcium Release Channel/metabolism
- Sarcolemma/metabolism
- Sarcoplasmic Reticulum Calcium-Transporting ATPases/genetics
- Sarcoplasmic Reticulum Calcium-Transporting ATPases/metabolism
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Affiliation(s)
- Ilanit Itzhaki
- Sohnis Family Research Laboratory for Cardiac Electrophysiology and Regenerative Medicine, Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Sophia Rapoport
- Department of Biophysics Physiology, Technion - Israel Institute of Technology, Haifa, Israel
| | - Irit Huber
- Sohnis Family Research Laboratory for Cardiac Electrophysiology and Regenerative Medicine, Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Itzhak Mizrahi
- Sohnis Family Research Laboratory for Cardiac Electrophysiology and Regenerative Medicine, Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Limor Zwi-Dantsis
- Sohnis Family Research Laboratory for Cardiac Electrophysiology and Regenerative Medicine, Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Gil Arbel
- Sohnis Family Research Laboratory for Cardiac Electrophysiology and Regenerative Medicine, Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Jackie Schiller
- Department of Biophysics Physiology, Technion - Israel Institute of Technology, Haifa, Israel
| | - Lior Gepstein
- Sohnis Family Research Laboratory for Cardiac Electrophysiology and Regenerative Medicine, Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
- * E-mail:
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Kobayashi T, Maeda S, Ichise N, Sato T, Iwase T, Seki S, Yamada Y, Tohse N. The beginning of the calcium transient in rat embryonic heart. J Physiol Sci 2011; 61:141-9. [PMID: 21267689 PMCID: PMC10717117 DOI: 10.1007/s12576-010-0131-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Accepted: 12/28/2010] [Indexed: 11/25/2022]
Abstract
Although many researchers have tried to observe the beginning of the heartbeat, no study has shown the beginning of the calcium transient. Here, we evaluate the beginning of the calcium transient in the Wistar rat heart. We first tried to reveal when the heart of the Wistar rat begins to contract because no previous study has evaluated the beginning of the heartbeat in Wistar rats. Observation of embryos transferred to a small incubator mounted on a microscope revealed that the heart primordium, the so-called cardiac crescent, began to contract at embryonic day 9.99-10.13. Observation of embryos loaded with fluo-3 AM revealed that the beginning of the calcium transient precedes the initiation of contraction which precedes the appearance of the linear heart tube. Nifedipine (1 μM), but not ryanodine (1 μM), abolished the calcium transients. These results indicate that calcium transients in the early embryonic period involve exclusively calcium entry through L-type calcium channels in contrast to the situation in mature hearts. This study provides the first demonstration of the relationship between morphological changes in the heart primordium and the beginning of the calcium transient and contraction.
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Affiliation(s)
- Takeshi Kobayashi
- Department of Cellular Physiology and Signal Transduction, Sapporo Medical University School of Medicine, South 1 West 17, Chuo-ku, Sapporo, 060-8556, Japan.
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Zahanich I, Sirenko SG, Maltseva LA, Tarasova YS, Spurgeon HA, Boheler KR, Stern MD, Lakatta EG, Maltsev VA. Rhythmic beating of stem cell-derived cardiac cells requires dynamic coupling of electrophysiology and Ca cycling. J Mol Cell Cardiol 2010; 50:66-76. [PMID: 20920509 DOI: 10.1016/j.yjmcc.2010.09.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2010] [Revised: 09/01/2010] [Accepted: 09/27/2010] [Indexed: 12/11/2022]
Abstract
There is an intense interest in differentiating embryonic stem cells to engineer biological pacemakers as an alternative to electronic pacemakers for patients with cardiac pacemaker function deficiency. Embryonic stem cell-derived cardiocytes (ESCs), however, often exhibit dysrhythmic excitations. Using Ca(2+) imaging and patch-clamp techniques, we studied requirements for generation of spontaneous rhythmic action potentials (APs) in late-stage mouse ESCs. Sarcoplasmic reticulum (SR) of ESCs generates spontaneous, rhythmic, wavelet-like Local Ca(2+)Releases (LCRs) (inhibited by ryanodine, tetracaine, or thapsigargin). L-type Ca(2+)current (I(CaL)) induces a global Ca(2+) release (CICR), depleting the Ca(2+) content SR which resets the phases of LCR oscillators. Following a delay, SR then generates a highly synchronized spontaneous Ca(2+)release of multiple LCRs throughout the cell. The LCRs generate an inward Na(+)/Ca(2+)exchanger (NCX) current (absent in Na(+)-free solution) that ignites the next AP. Interfering with SR Ca(2+) cycling (ryanodine, caffeine, thapsigargin, cyclopiazonic acid, BAPTA-AM), NCX (Na(+)-free solution), or I(CaL) (nifedipine) results in dysrhythmic excitations or cessation of automaticity. Inhibition of cAMP/PKA signaling by a specific PKA inhibitor, PKI, decreases SR Ca(2+) loading, substantially reducing both spontaneous LCRs (number, size, and amplitude) and rhythmic AP firing. In contrast, enhancing PKA signaling by cAMP increases the LCRs (number, size, duration) and converts irregularly beating ESCs to rhythmic "pacemaker-like" cells. SR Ca(2+) loading and LCR activity could be also increased with a selective activation of SR Ca(2+) pumping by a phospholamban antibody. We conclude that SR Ca(2+) loading and spontaneous rhythmic LCRs are driven by inherent cAMP/PKA activity. I(CaL) synchronizes multiple LCR oscillators resulting in strong, partially synchronized diastolic Ca(2+) release and NCX current. Rhythmic ESC automaticity can be achieved by boosting "coupling" factors, such as cAMP/PKA signaling, that enhance interactions between SR and sarcolemma.
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Affiliation(s)
- Ihor Zahanich
- Laboratory of Cardiovascular Science, IRP, NIA, NIH, Baltimore, MD 21224-6825, USA
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Janowski E, Berríos M, Cleemann L, Morad M. Developmental aspects of cardiac Ca(2+) signaling: interplay between RyR- and IP(3)R-gated Ca(2+) stores. Am J Physiol Heart Circ Physiol 2010; 298:H1939-50. [PMID: 20304819 DOI: 10.1152/ajpheart.00607.2009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The dominant mode of intracellular Ca(2+) release in adult mammalian heart is gated by ryanodine receptors (RyRs), but it is less clear whether inositol 1,4,5-trisphosphate (IP(3))-gated Ca(2+) release channels (IP(3)Rs), which are important during embryogenesis, play a significant role during early postnatal development. To address this question, we measured confocal two-dimensional Ca(2+) dependent fluorescence images in acutely isolated neonatal (days 1 to 2) and juvenile (days 8-10) rat cardiomyocytes, either voltage-clamped or permeabilized, where rapid exchange of solution could be used to selectively activate the two types of Ca(2+) release channel. Targeting RyRs with caffeine produced large and rapid Ca(2+) signals throughout the cells. Application of ATP and endothelin-1 to voltage-clamped, or IP(3) to permeabilized, cells produced smaller and slower Ca(2+) signals that were most prominent in subsarcolemmal regions and were suppressed by either the IP(3)R-blocker 2-aminoethoxydiphenylborate or replacement of the biologically active form of IP(3) with its L-stereoisomer. Such IP(3)R-gated Ca(2+) releases were amplified by Ca(2+)-induced Ca(2+) release (CICR) via RyRs since they were also reduced by compounds that block the RyRs (tetracaine) or deplete the Ca(2+) pools they gate (caffeine, ryanodine). Spatial analysis revealed both subsarcolemmal and perinuclear origins for the IP(3)-mediated Ca(2+) release events RyR- and IP(3)R-gated Ca(2+) signals had larger magnitudes in juvenile than in neonatal cardiomyocytes. Ca(2+) signaling was generally quite similar in atrial and ventricular cardiomyocytes but showed divergent development of IP(3)-mediated regulation in juveniles. Our data suggest that an intermediate stage of Ca(2+) signaling may be present in developing cardiomyocytes, where, in addition to RyR-gated Ca(2+) pools, IP(3)-gated Ca(2+) release is sufficiently large in magnitude and duration to trigger or contribute to activation of CICR and cardiac contraction.
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Lakatta EG, Maltsev VA, Vinogradova TM. A coupled SYSTEM of intracellular Ca2+ clocks and surface membrane voltage clocks controls the timekeeping mechanism of the heart's pacemaker. Circ Res 2010; 106:659-73. [PMID: 20203315 PMCID: PMC2837285 DOI: 10.1161/circresaha.109.206078] [Citation(s) in RCA: 453] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Ion channels on the surface membrane of sinoatrial nodal pacemaker cells (SANCs) are the proximal cause of an action potential. Each individual channel type has been thoroughly characterized under voltage clamp, and the ensemble of the ion channel currents reconstructed in silico generates rhythmic action potentials. Thus, this ensemble can be envisioned as a surface "membrane clock" (M clock). Localized subsarcolemmal Ca(2+) releases are generated by the sarcoplasmic reticulum via ryanodine receptors during late diastolic depolarization and are referred to as an intracellular "Ca(2+) clock," because their spontaneous occurrence is periodic during voltage clamp or in detergent-permeabilized SANCs, and in silico as well. In spontaneously firing SANCs, the M and Ca(2+) clocks do not operate in isolation but work together via numerous interactions modulated by membrane voltage, subsarcolemmal Ca(2+), and protein kinase A and CaMKII-dependent protein phosphorylation. Through these interactions, the 2 subsystem clocks become mutually entrained to form a robust, stable, coupled-clock system that drives normal cardiac pacemaker cell automaticity. G protein-coupled receptors signaling creates pacemaker flexibility, ie, effects changes in the rhythmic action potential firing rate, by impacting on these very same factors that regulate robust basal coupled-clock system function. This review examines evidence that forms the basis of this coupled-clock system concept in cardiac SANCs.
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Affiliation(s)
- Edward G Lakatta
- Laboratory of Cardiovascular Science, Gerontology Research Center, National Institute on Aging/NIH, 5600 Nathan Shock Dr., Baltimore, MD 21224-6825, USA.
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Tracqui P, Ohayon J. An integrated formulation of anisotropic force-calcium relations driving spatio-temporal contractions of cardiac myocytes. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2009; 367:4887-4905. [PMID: 19884185 DOI: 10.1098/rsta.2009.0149] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Isolated cardiac myocytes exhibit spontaneous patterns of rhythmic contraction, driven by intracellular calcium waves. In order to study the coupling between spatio-temporal calcium dynamics and cell contraction in large deformation regimes, a new strain-energy function, describing the influence of sarcomere length on the calcium-dependent generation of active intracellular stresses, is proposed. This strain-energy function includes anisotropic passive and active contributions that were first validated separately from experimental stress-strain curves and stress-sarcomere length curves, respectively. An extended validation of this formulation was then conducted by considering this strain-energy function as the core of an integrated mechano-chemical three-dimensional model of cardiac myocyte contraction, where autocatalytic intracellular calcium dynamics were described by a representative two-variable model able to generate realistic intracellular calcium waves similar to those observed experimentally. Finite-element simulations of the three-dimensional cell model, conducted for different intracellular locations of triggering calcium sparks, explained very satisfactorily, both qualitatively and quantitatively, the contraction patterns of cardiac myocytes observed by time-lapse videomicroscopy. This integrative approach of the mechano-chemical couplings driving cardiac myocyte contraction provides a comprehensive framework for analysing active stress regulation and associated mechano-transduction processes that contribute to the efficiency of cardiac cell contractility in both physiological and pathological contexts.
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Affiliation(s)
- Philippe Tracqui
- Laboratoire Techniques de l'Ingéniere Médicale et da Complexité - Informatique, Mathématiques et Applications de Grenoble, Equipe DynaCell, Unité Mixte de Recherche, Centre National de Recherche Scientifique 5525, Institut d'Ingénierie et de l'Information de Santé (In3S), Université Joseph Fourier, Faculté de Médecine de Grenoble, 38706 La Tronche Cedex, France.
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Sugimoto K, Okamura K, Tanaka H, Takashima S, Ochi H, Yamamoto T, Matoba R. Methamphetamine directly accelerates beating rate in cardiomyocytes by increasing Ca(2+) entry via L-type Ca(2+) channel. Biochem Biophys Res Commun 2009; 390:1214-20. [PMID: 19878660 DOI: 10.1016/j.bbrc.2009.10.124] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2009] [Accepted: 10/26/2009] [Indexed: 02/05/2023]
Abstract
Methamphetamine induces several cardiac dysfunctions, which leads to arrhythmia, cardiac failure and sudden cardiac death. Although these cardiac alterations elicited by methamphetamine were thought to be due to an indirect action of methamphetamine, namely, an excessive catecholamine release from synaptic terminals, while it seems likely that methamphetamine directly modulates the functioning of cardiomyocytes independent of neurotransmitters. However, the direct effects of methamphetamine on cardiomyocytes are still not clear. We show that methamphetamine directly accelerates the beating rate and alters Ca(2+) oscillation pattern in cultured neonatal rat cardiomyocytes. Adrenergic receptor antagonists did not block the methamphetamine-induced alterations in cardiomyocytes. Treatment with a ryanodine receptor type 2 inhibitor and a sarcoplasmic reticulum Ca(2+)-ATPase inhibitor did not affect these responses, either. In contrast, the L-type Ca(2+) channel inhibitor nifedipine eradicated these responses. Furthermore, methamphetamine elevated the internal free Ca(2+) concentration in HEK-293T cells stably transfected with the L-type Ca(2+) channel alpha1C subunit. In neonatal rat cardiomyocytes, methamphetamine accelerates beating rate and alters Ca(2+) oscillation pattern by increasing Ca(2+) entry via the L-type Ca(2+) channels independent of any neurotransmitters.
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Affiliation(s)
- Kana Sugimoto
- Department of Legal Medicine, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
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45
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Link S, Meissner M, Held B, Beck A, Weissgerber P, Freichel M, Flockerzi V. Diversity and developmental expression of L-type calcium channel beta2 proteins and their influence on calcium current in murine heart. J Biol Chem 2009; 284:30129-37. [PMID: 19723630 DOI: 10.1074/jbc.m109.045583] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
By now, little is known on L-type calcium channel (LTCC) subunits expressed in mouse heart. We show that CaVbeta2 proteins are the major CaVbeta components of the LTCC in embryonic and adult mouse heart, but that in embryonic heart CaVbeta3 proteins are also detectable. At least two CaVbeta2 variants of approximately 68 and approximately 72 kDa are expressed. To identify the underlying CaVbeta2 variants, cDNA libraries were constructed from poly(A)(+) RNA isolated from hearts of 7-day-old and adult mice. Screening identified 60 independent CaVbeta2 cDNA clones coding for four types of CaVbeta2 proteins only differing in their 5' sequences. CaVbeta2-N1, -N4, and -N5 but not -N3 were identified in isolated cardiomyocytes by RT-PCR and were sufficient to reconstitute the CaVbeta2 protein pattern in vitro. Significant L-type Ca(2+) currents (I(Ca)) were recorded in HEK293 cells after co-expression of CaV1.2 and CaVbeta2. Current kinetics were determined by the type of CaVbeta2 protein, with the approximately 72-kDa CaVbeta2a-N1 shifting the activation of I(Ca) significantly to depolarizing potentials compared with the other CaVbeta2 variants. Inactivation of I(Ca) was accelerated by CaVbeta2a-N1 and -N4, which also lead to slower activation compared with CaVbeta2a-N3 and -N5. In summary, this study reveals the molecular LTCC composition in mouse heart and indicates that expression of various CaVbeta2 proteins may be used to adapt the properties of LTCCs to changing myocardial requirements during development and that CaVbeta2a-N1-induced changes of I(Ca) kinetics might be essential in embryonic heart.
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Affiliation(s)
- Sabine Link
- Experimentelle und Klinische Pharmakologie und Toxikologie, Universität des Saarlandes, 66421 Homburg, Germany.
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Zhu WZ, Santana LF, Laflamme MA. Local control of excitation-contraction coupling in human embryonic stem cell-derived cardiomyocytes. PLoS One 2009; 4:e5407. [PMID: 19404384 PMCID: PMC2671137 DOI: 10.1371/journal.pone.0005407] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2008] [Accepted: 04/07/2009] [Indexed: 01/20/2023] Open
Abstract
We investigated the mechanisms of excitation-contraction (EC) coupling in human embryonic stem cell-derived cardiomyocytes (hESC-CMs) and fetal ventricular myocytes (hFVMs) using patch-clamp electrophysiology and confocal microscopy. We tested the hypothesis that Ca2+ influx via voltage-gated L-type Ca2+ channels activates Ca2+ release from the sarcoplasmic reticulum (SR) via a local control mechanism in hESC-CMs and hFVMs. Field-stimulated, whole-cell [Ca2+]i transients in hESC-CMs required Ca2+ entry through L-type Ca2+ channels, as evidenced by the elimination of such transients by either removal of extracellular Ca2+ or treatment with diltiazem, an L-type channel inhibitor. Ca2+ release from the SR also contributes to the [Ca2+]i transient in these cells, as evidenced by studies with drugs interfering with either SR Ca2+ release (i.e. ryanodine and caffeine) or reuptake (i.e. thapsigargin and cyclopiazonic acid). As in adult ventricular myocytes, membrane depolarization evoked large L-type Ca2+ currents (ICa) and corresponding whole-cell [Ca2+]i transients in hESC-CMs and hFVMs, and the amplitude of both ICa and the [Ca2+]i transients were finely graded by the magnitude of the depolarization. hESC-CMs exhibit a decreasing EC coupling gain with depolarization to more positive test potentials, “tail” [Ca2+]i transients upon repolarization from extremely positive test potentials, and co-localized ryanodine and sarcolemmal L-type Ca2+ channels, all findings that are consistent with the local control hypothesis. Finally, we recorded Ca2+ sparks in hESC-CMs and hFVMs. Collectively, these data support a model in which tight, local control of SR Ca2+ release by the ICa during EC coupling develops early in human cardiomyocytes.
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Affiliation(s)
- Wei-Zhong Zhu
- Department of Pathology, University of Washington, Seattle, Washington, United States of America
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, Washington, United States of America
| | - Luis F. Santana
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, Washington, United States of America
- Department of Physiology & Biophysics, University of Washington, Seattle, Washington, United States of America
- * E-mail: (LFS); (MAL)
| | - Michael A. Laflamme
- Department of Pathology, University of Washington, Seattle, Washington, United States of America
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, Washington, United States of America
- * E-mail: (LFS); (MAL)
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Automated analysis of contractility in the embryonic stem cell test, a novel approach to assess embryotoxicity. Toxicol In Vitro 2008; 22:1948-56. [DOI: 10.1016/j.tiv.2008.09.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2008] [Revised: 08/05/2008] [Accepted: 09/12/2008] [Indexed: 11/21/2022]
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48
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Ludwig A, Herrmann S, Hoesl E, Stieber J. Mouse models for studying pacemaker channel function and sinus node arrhythmia. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2008; 98:179-85. [DOI: 10.1016/j.pbiomolbio.2009.01.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Rapila R, Korhonen T, Tavi P. Excitation-contraction coupling of the mouse embryonic cardiomyocyte. ACTA ACUST UNITED AC 2008; 132:397-405. [PMID: 18794377 PMCID: PMC2553387 DOI: 10.1085/jgp.200809960] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In the mammalian embryo, the primitive tubular heart starts beating during the first trimester of gestation. These early heartbeats originate from calcium-induced contractions of the developing heart muscle cells. To explain the initiation of this activity, two ideas have been presented. One hypothesis supports the role of spontaneously activated voltage-gated calcium channels, whereas the other emphasizes the role of Ca(2+) release from intracellular stores initiating spontaneous intracellular calcium oscillations. We show with experiments that both of these mechanisms coexist and operate in mouse cardiomyocytes during embryonic days 9-11. Further, we characterize how inositol-3-phosphate receptors regulate the frequency of the sarcoplasmic reticulum calcium oscillations and thus the heartbeats. This study provides a novel view of the regulation of embryonic cardiomyocyte activity, explaining the functional versatility of developing cardiomyocytes and the origin and regulation of the embryonic heartbeat.
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Affiliation(s)
- Risto Rapila
- Institute of Biomedicine, Department of Physiology and Biocenter Oulu, University of Oulu, 90014 Oulu, Finland
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50
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Abstract
The heart automaticity is a fundamental physiological function in higher organisms. The spontaneous activity is initiated by specialized populations of cardiac cells generating periodical electrical oscillations. The exact cascade of steps initiating the pacemaker cycle in automatic cells has not yet been entirely elucidated. Nevertheless, ion channels and intracellular Ca(2+) signaling are necessary for the proper setting of the pacemaker mechanism. Here, we review the current knowledge on the cellular mechanisms underlying the generation and regulation of cardiac automaticity. We discuss evidence on the functional role of different families of ion channels in cardiac pacemaking and review recent results obtained on genetically engineered mouse strains displaying dysfunction in heart automaticity. Beside ion channels, intracellular Ca(2+) release has been indicated as an important mechanism for promoting automaticity at rest as well as for acceleration of the heart rate under sympathetic nerve input. The potential links between the activity of ion channels and Ca(2+) release will be discussed with the aim to propose an integrated framework of the mechanism of automaticity.
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Affiliation(s)
- Matteo E Mangoni
- Institute of Functional Genomics, Department of Physiology, Centre National de la Recherche Scientifique UMR5203, INSERM U661, University of Montpellier I and II, Montpellier, France.
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