1
|
Ruffinatti FA, Scarpellino G, Chinigò G, Visentin L, Munaron L. The Emerging Concept of Transportome: State of the Art. Physiology (Bethesda) 2023; 38:0. [PMID: 37668550 DOI: 10.1152/physiol.00010.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 09/01/2023] [Accepted: 09/01/2023] [Indexed: 09/06/2023] Open
Abstract
The array of ion channels and transporters expressed in cell membranes, collectively referred to as the transportome, is a complex and multifunctional molecular machinery; in particular, at the plasma membrane level it finely tunes the exchange of biomolecules and ions, acting as a functionally adaptive interface that accounts for dynamic plasticity in the response to environmental fluctuations and stressors. The transportome is responsible for the definition of membrane potential and its variations, participates in the transduction of extracellular signals, and acts as a filter for most of the substances entering and leaving the cell, thus enabling the homeostasis of many cellular parameters. For all these reasons, physiologists have long been interested in the expression and functionality of ion channels and transporters, in both physiological and pathological settings and across the different domains of life. Today, thanks to the high-throughput technologies of the postgenomic era, the omics approach to the study of the transportome is becoming increasingly popular in different areas of biomedical research, allowing for a more comprehensive, integrated, and functional perspective of this complex cellular apparatus. This article represents a first effort for a systematic review of the scientific literature on this topic. Here we provide a brief overview of all those studies, both primary and meta-analyses, that looked at the transportome as a whole, regardless of the biological problem or the models they used. A subsequent section is devoted to the methodological aspect by reviewing the most important public databases annotating ion channels and transporters, along with the tools they provide to retrieve such information. Before conclusions, limitations and future perspectives are also discussed.
Collapse
Affiliation(s)
- Federico Alessandro Ruffinatti
- Turin Cell Physiology Laboratory (TCP-Lab), Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| | - Giorgia Scarpellino
- Turin Cell Physiology Laboratory (TCP-Lab), Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| | - Giorgia Chinigò
- Turin Cell Physiology Laboratory (TCP-Lab), Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| | - Luca Visentin
- Turin Cell Physiology Laboratory (TCP-Lab), Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| | - Luca Munaron
- Turin Cell Physiology Laboratory (TCP-Lab), Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| |
Collapse
|
2
|
Souza DS, Chignalia AZ, Carvalho-de-Souza JL. Modulation of cardiac voltage-activated K + currents by glypican 1 heparan sulfate proteoglycan. Life Sci 2022; 308:120916. [PMID: 36049528 PMCID: PMC11105158 DOI: 10.1016/j.lfs.2022.120916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 08/15/2022] [Accepted: 08/24/2022] [Indexed: 11/20/2022]
Abstract
BACKGROUND Glypican 1 (Gpc1) is a heparan sulfate proteoglycan attached to the cell membrane via a glycosylphosphatidylinositol anchor, where it holds glycosaminoglycans nearby. We have recently shown that Gpc1 knockout (Gpc1-/-) mice feature decreased systemic blood pressure. To date, none has been reported regarding the role of Gpc1 on the electrical properties of the heart and specifically, in regard to a functional interaction between Gpc1 and voltage-gated K+ channels. METHODS We used echocardiography and in vivo (electrocardiographic recordings) and in vitro (patch clamping) electrophysiology to study mechanical and electric properties of mice hearts. We used RT-PCR to probe K+ channels' gene transcription in heart tissue. RESULTS Gpc1-/- hearts featured increased cardiac stroke volume and preserved ejection fraction. Gpc1-/- electrocardiograms showed longer QT intervals, abnormalities in the ST segment, and delayed T waves, corroborated by longer action potentials in isolated ventricular cardiomyocytes. In voltage-clamp, these cells showed decreased Ito and IK voltage-activated K+ current densities. Moreover, IK showed activation at less negative voltages, but a higher level of inactivation at a given membrane potential. Kcnh2 and Kcnq1 voltage-gated K+ channels subunits' transcripts were remarkably more abundant in heart tissues from Gpc1-/- mice, suggesting that Gpc1 may interfere in the steps between transcription and translation in these cases. CONCLUSION Our data reveals an unprecedented connection between Gpc1 and voltage-gated K+ channels expressed in the heart and this knowledge contributes to the understanding of the role of this HSPG in cardiac function which may play a role in the development of cardiovascular disease.
Collapse
Affiliation(s)
- Diego Santos Souza
- Department of Anesthesiology, College of Medicine, University of Arizona, Tucson, AZ 85724, USA
| | - Andreia Zago Chignalia
- Department of Anesthesiology, College of Medicine, University of Arizona, Tucson, AZ 85724, USA; Department of Physiology, College of Medicine University of Arizona, Tucson, AZ 85724, USA; Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, AZ 85724, USA
| | - Joao Luis Carvalho-de-Souza
- Department of Anesthesiology, College of Medicine, University of Arizona, Tucson, AZ 85724, USA; Department of Physiology, College of Medicine University of Arizona, Tucson, AZ 85724, USA; Department of Ophthalmology and Visual Sciences, College of Medicine, University of Arizona, Tucson, AZ 85724, USA; BIO5 Institute, University of Arizona, Tucson, AZ 85724, USA.
| |
Collapse
|
3
|
Reilly L, Munawar S, Zhang J, Crone WC, Eckhardt LL. Challenges and innovation: Disease modeling using human-induced pluripotent stem cell-derived cardiomyocytes. Front Cardiovasc Med 2022; 9:966094. [PMID: 36035948 PMCID: PMC9411865 DOI: 10.3389/fcvm.2022.966094] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 07/19/2022] [Indexed: 11/29/2022] Open
Abstract
Disease modeling using human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) has both challenges and promise. While patient-derived iPSC-CMs provide a unique opportunity for disease modeling with isogenic cells, the challenge is that these cells still demonstrate distinct properties which make it functionally less akin to adult cardiomyocytes. In response to this challenge, numerous innovations in differentiation and modification of hiPSC-CMs and culture techniques have been developed. Here, we provide a focused commentary on hiPSC-CMs for use in disease modeling, the progress made in generating electrically and metabolically mature hiPSC-CMs and enabling investigative platforms. The solutions are bringing us closer to the promise of modeling heart disease using human cells in vitro.
Collapse
Affiliation(s)
- Louise Reilly
- Cellular and Molecular Arrhythmia Research Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States
| | - Saba Munawar
- Cellular and Molecular Arrhythmia Research Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States
| | - Jianhua Zhang
- Cellular and Molecular Arrhythmia Research Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States
| | - Wendy C. Crone
- Department of Engineering Physics, College of Engineering, University of Wisconsin-Madison, Madison, WI, United States
| | - Lee L. Eckhardt
- Cellular and Molecular Arrhythmia Research Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States,*Correspondence: Lee L. Eckhardt
| |
Collapse
|
4
|
Darche FF, Ullrich ND, Huang Z, Koenen M, Rivinius R, Frey N, Schweizer PA. Improved Generation of Human Induced Pluripotent Stem Cell-Derived Cardiac Pacemaker Cells Using Novel Differentiation Protocols. Int J Mol Sci 2022; 23:ijms23137318. [PMID: 35806319 PMCID: PMC9266442 DOI: 10.3390/ijms23137318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 06/27/2022] [Accepted: 06/28/2022] [Indexed: 02/01/2023] Open
Abstract
Current protocols for the differentiation of human-induced pluripotent stem cells (hiPSC) into cardiomyocytes only generate a small amount of cardiac pacemaker cells. In previous work, we reported the generation of high amounts of cardiac pacemaker cells by co-culturing hiPSC with mouse visceral endoderm-like (END2) cells. However, potential medical applications of cardiac pacemaker cells generated according to this protocol, comprise an incalculable xenogeneic risk. We thus aimed to establish novel protocols maintaining the differentiation efficiency of the END2 cell-based protocol, yet eliminating the use of END2 cells. Three protocols were based on the activation and inhibition of the Wingless/Integrated (Wnt) signaling pathway, supplemented either with retinoic acid and the Wnt activator CHIR99021 (protocol B) or with the NODAL inhibitor SB431542 (protocol C) or with a combination of all three components (protocol D). An additional fourth protocol (protocol E) was used, which was originally developed by the manufacturer STEMCELL Technologies for the differentiation of hiPSC or hESC into atrial cardiomyocytes. All protocols (B, C, D, E) were compared to the END2 cell-based protocol A, serving as reference, in terms of their ability to differentiate hiPSC into cardiac pacemaker cells. Our analysis revealed that protocol E induced upregulation of 12 out of 15 cardiac pacemaker-specific genes. For comparison, reference protocol A upregulated 11, while protocols B, C and D upregulated 9, 10 and 8 cardiac pacemaker-specific genes, respectively. Cells differentiated according to protocol E displayed intense fluorescence signals of cardiac pacemaker-specific markers and showed excellent rate responsiveness to adrenergic and cholinergic stimulation. In conclusion, we characterized four novel and END2 cell-independent protocols for the differentiation of hiPSC into cardiac pacemaker cells, of which protocol E was the most efficient.
Collapse
Affiliation(s)
- Fabrice F. Darche
- Department of Cardiology, Angiology and Pneumology, Heidelberg University Hospital, 69120 Heidelberg, Germany; (M.K.); (R.R.); (N.F.); (P.A.S.)
- German Center for Cardiovascular Research (DZHK), Partner Site Heidelberg/Mannheim, 69120 Heidelberg, Germany;
- Correspondence: ; Tel.: +49-6221-56-8676; Fax: +49-6221-56-5515
| | - Nina D. Ullrich
- German Center for Cardiovascular Research (DZHK), Partner Site Heidelberg/Mannheim, 69120 Heidelberg, Germany;
- Institute of Physiology and Pathophysiology, Heidelberg University, 69120 Heidelberg, Germany
| | - Ziqiang Huang
- EMBL Imaging Centre, European Molecular Biology Laboratory (EMBL), Meyerhofstraße 1, 69117 Heidelberg, Germany;
| | - Michael Koenen
- Department of Cardiology, Angiology and Pneumology, Heidelberg University Hospital, 69120 Heidelberg, Germany; (M.K.); (R.R.); (N.F.); (P.A.S.)
- Department of Molecular Neurobiology, Max-Planck-Institute for Medical Research, Jahnstraße 29, 69120 Heidelberg, Germany
| | - Rasmus Rivinius
- Department of Cardiology, Angiology and Pneumology, Heidelberg University Hospital, 69120 Heidelberg, Germany; (M.K.); (R.R.); (N.F.); (P.A.S.)
- German Center for Cardiovascular Research (DZHK), Partner Site Heidelberg/Mannheim, 69120 Heidelberg, Germany;
| | - Norbert Frey
- Department of Cardiology, Angiology and Pneumology, Heidelberg University Hospital, 69120 Heidelberg, Germany; (M.K.); (R.R.); (N.F.); (P.A.S.)
- German Center for Cardiovascular Research (DZHK), Partner Site Heidelberg/Mannheim, 69120 Heidelberg, Germany;
| | - Patrick A. Schweizer
- Department of Cardiology, Angiology and Pneumology, Heidelberg University Hospital, 69120 Heidelberg, Germany; (M.K.); (R.R.); (N.F.); (P.A.S.)
- German Center for Cardiovascular Research (DZHK), Partner Site Heidelberg/Mannheim, 69120 Heidelberg, Germany;
| |
Collapse
|
5
|
Kim KH, Oh Y, Liu J, Dababneh S, Xia Y, Kim RY, Kim DK, Ban K, Husain M, Hui CC, Backx PH. Irx5 and transient outward K + currents contribute to transmural contractile heterogeneities in the mouse ventricle. Am J Physiol Heart Circ Physiol 2022; 322:H725-H741. [PMID: 35245131 DOI: 10.1152/ajpheart.00572.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous studies have established that fast transmural gradients of transient outward K+ current (Ito,f) correlate with regional differences in action potential (AP) profile and excitation-contraction coupling (ECC) with high Ito,f expression in the epimyocardium (EPI) being associated with short APs and low contractility and vice versa. Herein, we investigated the effects of disrupted Ito,f gradient on contractile properties using mouse models of Irx5 knockout (Irx5-KO) for selective Ito,f elevation in the endomyocardium (ENDO) of the left ventricle (LV) and Kcnd2 ablation (KV4.2-KO) for selective Ito,freduction in the EPI. Irx5-KO mice exhibited decreased global LV contractility in association with reductions in cell shortening and Ca2+ transient amplitudes in isolated ENDO but not EPI cardiomyocytes. Moreover, transcriptional profiling revealed that the primary effect of Irx5 ablation on ECC-related genes was to increase Ito,f gene expression (i.e. Kcnd2 and Kcnip2) in the ENDO, but not the EPI. Indeed, KV4.2-KO mice showed selective increases in cell shortening and Ca2+ transients in isolated EPI cardiomyocytes, leading to enhanced ventricular contractility and mice lacking both Irx5 and Kcnd2 displayed elevated ventricular contractility comparable to KV4.2-KO mice. Our findings demonstrate that the transmural electromechanical heterogeneities in the healthy ventricles depend on the Irx5-dependent Ito,f gradients. These observations provide a useful framework for assessing the molecular mechanisms underlying the alterations in contractile heterogeneity seen in the diseased heart.
Collapse
Affiliation(s)
- Kyoung-Han Kim
- University of Ottawa Heart Institute, Ottawa, ON, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada.,Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Yena Oh
- University of Ottawa Heart Institute, Ottawa, ON, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Jie Liu
- Department of Physiology, University of Toronto, Toronto, ON, Canada.,Department of Biology, Faculty of Science, York University, Toronto, ON, Canada
| | - Saif Dababneh
- University of Ottawa Heart Institute, Ottawa, ON, Canada
| | - Ying Xia
- University of Ottawa Heart Institute, Ottawa, ON, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Ri Youn Kim
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Dae-Kyum Kim
- University of Ottawa Heart Institute, Ottawa, ON, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Kiwon Ban
- Department of Physiology, University of Toronto, Toronto, ON, Canada.,Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China
| | - Mansoor Husain
- Department of Physiology, University of Toronto, Toronto, ON, Canada.,Toronto General Research Institute, University Health Network, Toronto, ON, Canada
| | - Chi-Chung Hui
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Peter H Backx
- Department of Physiology, University of Toronto, Toronto, ON, Canada.,Department of Biology, Faculty of Science, York University, Toronto, ON, Canada.,Toronto General Research Institute, University Health Network, Toronto, ON, Canada
| |
Collapse
|
6
|
Hager NA, McAtee CK, Lesko MA, O’Donnell AF. Inwardly Rectifying Potassium Channel Kir2.1 and its "Kir-ious" Regulation by Protein Trafficking and Roles in Development and Disease. Front Cell Dev Biol 2022; 9:796136. [PMID: 35223865 PMCID: PMC8864065 DOI: 10.3389/fcell.2021.796136] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Accepted: 12/15/2021] [Indexed: 11/13/2022] Open
Abstract
Potassium (K+) homeostasis is tightly regulated for optimal cell and organismal health. Failure to control potassium balance results in disease, including cardiac arrythmias and developmental disorders. A family of inwardly rectifying potassium (Kir) channels helps cells maintain K+ levels. Encoded by KCNJ genes, Kir channels are comprised of a tetramer of Kir subunits, each of which contains two-transmembrane domains. The assembled Kir channel generates an ion selectivity filter for K+ at the monomer interface, which allows for K+ transit. Kir channels are found in many cell types and influence K+ homeostasis across the organism, impacting muscle, nerve and immune function. Kir2.1 is one of the best studied family members with well-defined roles in regulating heart rhythm, muscle contraction and bone development. Due to their expansive roles, it is not surprising that Kir mutations lead to disease, including cardiomyopathies, and neurological and metabolic disorders. Kir malfunction is linked to developmental defects, including underdeveloped skeletal systems and cerebellar abnormalities. Mutations in Kir2.1 cause the periodic paralysis, cardiac arrythmia, and developmental deficits associated with Andersen-Tawil Syndrome. Here we review the roles of Kir family member Kir2.1 in maintaining K+ balance with a specific focus on our understanding of Kir2.1 channel trafficking and emerging roles in development and disease. We provide a synopsis of the vital work focused on understanding the trafficking of Kir2.1 and its role in development.
Collapse
Affiliation(s)
| | | | | | - Allyson F. O’Donnell
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, United States
| |
Collapse
|
7
|
Wang L, Wada Y, Ballan N, Schmeckpeper J, Huang J, Rau CD, Wang Y, Gepstein L, Knollmann BC. Triiodothyronine and dexamethasone alter potassium channel expression and promote electrophysiological maturation of human-induced pluripotent stem cell-derived cardiomyocytes. J Mol Cell Cardiol 2021; 161:130-138. [PMID: 34400182 PMCID: PMC9809541 DOI: 10.1016/j.yjmcc.2021.08.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 08/04/2021] [Accepted: 08/05/2021] [Indexed: 01/07/2023]
Abstract
BACKGROUND Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have emerged as a promising tool for disease modeling and drug development. However, hiPSC-CMs remain functionally immature, which hinders their utility as a model of human cardiomyocytes. OBJECTIVE To improve the electrophysiological maturation of hiPSC-CMs. METHODS AND RESULTS On day 16 of cardiac differentiation, hiPSC-CMs were treated with 100 nmol/L triiodothyronine (T3) and 1 μmol/L Dexamethasone (Dex) or vehicle for 14 days. On day 30, vehicle- and T3 + Dex-treated hiPSC-CMs were dissociated and replated either as cell sheets or single cells. Optical mapping and patch-clamp technique were used to examine the electrophysiological properties of vehicle- and T3 + Dex-treated hiPSC-CMs. Compared to vehicle, T3 + Dex-treated hiPSC-CMs had a slower spontaneous beating rate, more hyperpolarized resting membrane potential, faster maximal upstroke velocity, and shorter action potential duration. Changes in spontaneous activity and action potential were mediated by decreased hyperpolarization-activated current (If) and increased inward rectifier potassium currents (IK1), sodium currents (INa), and the rapidly and slowly activating delayed rectifier potassium currents (IKr and IKs, respectively). Furthermore, T3 + Dex-treated hiPSC-CM cell sheets (hiPSC-CCSs) exhibited a faster conduction velocity and shorter action potential duration than the vehicle. Inhibition of IK1 by 100 μM BaCl2 significantly slowed conduction velocity and prolonged action potential duration in T3 + Dex-treated hiPSC-CCSs but had no effect in the vehicle group, demonstrating the importance of IK1 for conduction velocity and action potential duration. CONCLUSION T3 + Dex treatment is an effective approach to rapidly enhance electrophysiological maturation of hiPSC-CMs.
Collapse
Affiliation(s)
- Lili Wang
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, Medical Research Building IV, Rm.1275, 2215B Garland Ave, Nashville, TN 37232, USA,Correspondence to: Lili Wang, Ph.D., Division of Clinical Pharmacology, Vanderbilt University Medical Center, Medical Research Building IV, Rm.1275, 2215B Garland Ave, Nashville, TN 37232-0575 Or Bjorn C. Knollmann, MD, Ph.D., Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Vanderbilt, University Medical Center, Medical Research Building IV, Rm. 1265, 2215B Garland Ave, Nashville, TN 37232-0575,
| | - Yuko Wada
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, Medical Research Building IV, Rm.1275, 2215B Garland Ave, Nashville, TN 37232, USA
| | - Nimer Ballan
- Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, POB 9649, Haifa 3109601, Israel
| | - Jeffrey Schmeckpeper
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, Medical Research Building IV, Rm.1275, 2215B Garland Ave, Nashville, TN 37232, USA
| | - Jijun Huang
- Department of Anesthesiology, Medicine and Physiology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA
| | - Christoph Daniel Rau
- Department of Anesthesiology, Medicine and Physiology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA
| | - Yibin Wang
- Department of Anesthesiology, Medicine and Physiology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA
| | - Lior Gepstein
- Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, POB 9649, Haifa 3109601, Israel,Cardiology Department, Rambam Health Care Campus, Rappaport Faculty of Medicine, Technion – Israel Institute of Technology, 2 Efron St. POB 9649, Haifa, 3109601, Israel
| | - Bjorn C. Knollmann
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, Medical Research Building IV, Rm.1275, 2215B Garland Ave, Nashville, TN 37232, USA,Correspondence to: Lili Wang, Ph.D., Division of Clinical Pharmacology, Vanderbilt University Medical Center, Medical Research Building IV, Rm.1275, 2215B Garland Ave, Nashville, TN 37232-0575 Or Bjorn C. Knollmann, MD, Ph.D., Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Vanderbilt, University Medical Center, Medical Research Building IV, Rm. 1265, 2215B Garland Ave, Nashville, TN 37232-0575,
| |
Collapse
|
8
|
Nowak MB, Veeraraghavan R, Poelzing S, Weinberg SH. Cellular Size, Gap Junctions, and Sodium Channel Properties Govern Developmental Changes in Cardiac Conduction. Front Physiol 2021; 12:731025. [PMID: 34759834 PMCID: PMC8573326 DOI: 10.3389/fphys.2021.731025] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 09/28/2021] [Indexed: 11/26/2022] Open
Abstract
Electrical conduction in cardiac ventricular tissue is regulated via sodium (Na+) channels and gap junctions (GJs). We and others have recently shown that Na+channels preferentially localize at the site of cell-cell junctions, the intercalated disc (ID), in adult cardiac tissue, facilitating coupling via the formation of intercellular Na+nanodomains, also termed ephaptic coupling (EpC). Several properties governing EpC vary with age, including Na+channel and GJ expression and distribution and cell size. Prior work has shown that neonatal cardiomyocytes have immature IDs with Na+channels and GJs diffusively distributed throughout the sarcolemma, while adult cells have mature IDs with preferentially localized Na+channels and GJs. In this study, we perform an in silico investigation of key age-dependent properties to determine developmental regulation of cardiac conduction. Simulations predict that conduction velocity (CV) biphasically depends on cell size, depending on the strength of GJ coupling. Total cell Na+channel conductance is predictive of CV in cardiac tissue with high GJ coupling, but not correlated with CV for low GJ coupling. We find that ephaptic effects are greatest for larger cells with low GJ coupling typically associated with intermediate developmental stages. Finally, simulations illustrate how variability in cellular properties during different developmental stages can result in a range of possible CV values, with a narrow range for both neonatal and adult myocardium but a much wider range for an intermediate developmental stage. Thus, we find that developmental changes predict associated changes in cardiac conduction.
Collapse
Affiliation(s)
- Madison B Nowak
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, United States
| | - Rengasayee Veeraraghavan
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, United States.,The Ohio State University Wexner Medical Center, Davis Heart and Lung Research Institute, Columbus, OH, United States
| | - Steven Poelzing
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States.,Virginia Polytechnic Institute and State University, Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA, United States
| | - Seth H Weinberg
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, United States.,The Ohio State University Wexner Medical Center, Davis Heart and Lung Research Institute, Columbus, OH, United States
| |
Collapse
|
9
|
Nowak MB, Poelzing S, Weinberg SH. Mechanisms underlying age-associated manifestation of cardiac sodium channel gain-of-function. J Mol Cell Cardiol 2021; 153:60-71. [PMID: 33373643 PMCID: PMC8026540 DOI: 10.1016/j.yjmcc.2020.12.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 12/04/2020] [Accepted: 12/06/2020] [Indexed: 10/22/2022]
Abstract
Cardiac action potentials are initiated by sodium ion (Na+) influx through voltage-gated Na+ channels. Na+ channel gain-of-function (GOF) can arise in inherited conditions due to mutations in the gene encoding the cardiac Na+ channel, such as Long QT syndrome type 3 (LQT3). LQT3 can be a "concealed" disease, as patients with LQT3-associated mutations can remain asymptomatic until later in life; however, arrhythmias can also arise early in life in LQT3 patients, demonstrating a complex age-associated manifestation. We and others recently demonstrated that cardiac Na+ channels preferentially localize at the intercalated disc (ID) in adult cardiac tissue, which facilitates ephaptic coupling and formation of intercellular Na+ nanodomains that regulate pro-arrhythmic early afterdepolarization (EAD) formation in tissue with Na+ channel GOF. Several properties related to ephaptic coupling vary with age, such as cell size and Na+ channel and gap junction (GJ) expression and distribution: neonatal cells have immature IDs, with Na+ channels and GJs primarily diffusively distributed, while adult myocytes have mature IDs with preferentially localized Na+ channels and GJs. Here, we perform an in silico study varying critical age-dependent parameters to investigate mechanisms underlying age-associated manifestation of Na+ channel GOF in a model of guinea pig cardiac tissue. Simulations predict that total Na+ current conductance is a critical factor in action potential duration (APD) prolongation. We find a complex cell size/ Na+ channel expression relationship: increases in cell size (without concurrent increases in Na+ channel expression) suppress EAD formation, while increases in Na+ channel expression (without concurrent increases in cell size) promotes EAD formation. Finally, simulations with neonatal and early age-associated parameters predict normal APD with minimal dependence on intercellular cleft width; however, variability in cellular properties can lead to EADs presenting in early developmental stages. In contrast, for adult-associated parameters, EAD formation is highly dependent on cleft width, consistent with a mechanism underlying the age-associated manifestation of the Na+ channel GOF.
Collapse
Affiliation(s)
- Madison B Nowak
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, United States of America
| | - Steven Poelzing
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States of America; Fralin Biomedical Research Institute at Virginia Tech Carilion, Virginia Polytechnic Institute and State University, Roanoke, VA, United States of America
| | - Seth H Weinberg
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, United States of America; Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States of America.
| |
Collapse
|
10
|
van der Pol A, Hoes MF, de Boer RA, van der Meer P. Cardiac foetal reprogramming: a tool to exploit novel treatment targets for the failing heart. J Intern Med 2020; 288:491-506. [PMID: 32557939 PMCID: PMC7687159 DOI: 10.1111/joim.13094] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 03/26/2020] [Accepted: 04/14/2020] [Indexed: 12/11/2022]
Abstract
As the heart matures during embryogenesis from its foetal stages, several structural and functional modifications take place to form the adult heart. This process of maturation is in large part due to an increased volume and work load of the heart to maintain proper circulation throughout the growing body. In recent years, it has been observed that these changes are reversed to some extent as a result of cardiac disease. The process by which this occurs has been characterized as cardiac foetal reprogramming and is defined as the suppression of adult and re-activation of a foetal genes profile in the diseased myocardium. The reasons as to why this process occurs in the diseased myocardium are unknown; however, it has been suggested to be an adaptive process to counteract deleterious events taking place during cardiac remodelling. Although still in its infancy, several studies have demonstrated that targeting foetal reprogramming in heart failure can lead to substantial improvement in cardiac functionality. This is highlighted by a recent study which found that by modulating the expression of 5-oxoprolinase (OPLAH, a novel cardiac foetal gene), cardiac function can be significantly improved in mice exposed to cardiac injury. Additionally, the utilization of angiotensin receptor neprilysin inhibitors (ARNI) has demonstrated clear benefits, providing important clinical proof that drugs that increase natriuretic peptide levels (part of the foetal gene programme) indeed improve heart failure outcomes. In this review, we will highlight the most important aspects of cardiac foetal reprogramming and will discuss whether this process is a cause or consequence of heart failure. Based on this, we will also explain how a deeper understanding of this process may result in the development of novel therapeutic strategies in heart failure.
Collapse
Affiliation(s)
- A van der Pol
- From the, Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.,Perioperative Inflammation and Infection Group, Department of Medicine, Faculty of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany
| | - M F Hoes
- From the, Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - R A de Boer
- From the, Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - P van der Meer
- From the, Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| |
Collapse
|
11
|
Abstract
Voltage-gated Kv1.1 potassium channel α-subunits are broadly expressed in the nervous system where they act as critical regulators of neuronal excitability. Mutations in the KCNA1 gene, which encodes Kv1.1, are associated with the neurological diseases episodic ataxia and epilepsy. Studies in mouse models have shown that Kv1.1 is important for neural control of the heart and that Kcna1 deletion leads to cardiac dysfunction that appears to be brain-driven. Traditionally, KCNA1 was not believed to be expressed in the heart. However, recent studies have revealed that Kv1.1 subunits are not only present in cardiomyocytes, but that they also make an important heart-intrinsic functional contribution to outward K+ currents and action potential repolarization. This review recounts the winding history of discovery of KCNA1 gene expression and neurocardiac function from fruit flies to mammals and from brain to heart and looks at some of the salient questions that remain to be answered regarding emerging cardiac roles of Kv1.1.
Collapse
Affiliation(s)
- Edward Glasscock
- a Department of Biological Sciences , Southern Methodist University , Dallas , TX , USA
| |
Collapse
|
12
|
Talman V, Teppo J, Pöhö P, Movahedi P, Vaikkinen A, Karhu ST, Trošt K, Suvitaival T, Heikkonen J, Pahikkala T, Kotiaho T, Kostiainen R, Varjosalo M, Ruskoaho H. Molecular Atlas of Postnatal Mouse Heart Development. J Am Heart Assoc 2019; 7:e010378. [PMID: 30371266 PMCID: PMC6474944 DOI: 10.1161/jaha.118.010378] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Background The molecular mechanisms mediating postnatal loss of cardiac regeneration in mammals are not fully understood. We aimed to provide an integrated resource of mRNA, protein, and metabolite changes in the neonatal heart for identification of metabolism‐related mechanisms associated with cardiac regeneration. Methods and Results Mouse ventricular tissue samples taken on postnatal day 1 (P01), P04, P09, and P23 were analyzed with RNA sequencing and global proteomics and metabolomics. Gene ontology analysis, KEGG pathway analysis, and fuzzy c‐means clustering were used to identify up‐ or downregulated biological processes and metabolic pathways on all 3 levels, and Ingenuity pathway analysis (Qiagen) was used to identify upstream regulators. Differential expression was observed for 8547 mRNAs and for 1199 of 2285 quantified proteins. Furthermore, 151 metabolites with significant changes were identified. Differentially regulated metabolic pathways include branched chain amino acid degradation (upregulated at P23), fatty acid metabolism (upregulated at P04 and P09; downregulated at P23) as well as the HMGCS (HMG‐CoA [hydroxymethylglutaryl‐coenzyme A] synthase)–mediated mevalonate pathway and ketogenesis (transiently activated). Pharmacological inhibition of HMGCS in primary neonatal cardiomyocytes reduced the percentage of BrdU‐positive cardiomyocytes, providing evidence that the mevalonate and ketogenesis routes may participate in regulating the cardiomyocyte cell cycle. Conclusions This study is the first systems‐level resource combining data from genomewide transcriptomics with global quantitative proteomics and untargeted metabolomics analyses in the mouse heart throughout the early postnatal period. These integrated data of molecular changes associated with the loss of cardiac regeneration may open up new possibilities for the development of regenerative therapies.
Collapse
Affiliation(s)
- Virpi Talman
- 1 Drug Research Program and Division of Pharmacology and Pharmacotherapy Faculty of Pharmacy University of Helsinki Finland
| | - Jaakko Teppo
- 2 Drug Research Program and Division of Pharmaceutical Chemistry and Technology Faculty of Pharmacy University of Helsinki Finland.,3 Institute of Biotechnology and HiLIFE Helsinki Institute of Life Science University of Helsinki Finland
| | - Päivi Pöhö
- 2 Drug Research Program and Division of Pharmaceutical Chemistry and Technology Faculty of Pharmacy University of Helsinki Finland
| | - Parisa Movahedi
- 4 Department of Future Technologies Faculty of Mathematics and Natural Sciences University of Turku Finland
| | - Anu Vaikkinen
- 2 Drug Research Program and Division of Pharmaceutical Chemistry and Technology Faculty of Pharmacy University of Helsinki Finland
| | - S Tuuli Karhu
- 1 Drug Research Program and Division of Pharmacology and Pharmacotherapy Faculty of Pharmacy University of Helsinki Finland
| | | | | | - Jukka Heikkonen
- 4 Department of Future Technologies Faculty of Mathematics and Natural Sciences University of Turku Finland
| | - Tapio Pahikkala
- 4 Department of Future Technologies Faculty of Mathematics and Natural Sciences University of Turku Finland
| | - Tapio Kotiaho
- 2 Drug Research Program and Division of Pharmaceutical Chemistry and Technology Faculty of Pharmacy University of Helsinki Finland.,6 Department of Chemistry Faculty of Science University of Helsinki Finland
| | - Risto Kostiainen
- 2 Drug Research Program and Division of Pharmaceutical Chemistry and Technology Faculty of Pharmacy University of Helsinki Finland
| | - Markku Varjosalo
- 3 Institute of Biotechnology and HiLIFE Helsinki Institute of Life Science University of Helsinki Finland
| | - Heikki Ruskoaho
- 1 Drug Research Program and Division of Pharmacology and Pharmacotherapy Faculty of Pharmacy University of Helsinki Finland
| |
Collapse
|
13
|
Learn from Your Elders: Developmental Biology Lessons to Guide Maturation of Stem Cell-Derived Cardiomyocytes. Pediatr Cardiol 2019; 40:1367-1387. [PMID: 31388700 PMCID: PMC6786957 DOI: 10.1007/s00246-019-02165-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Accepted: 07/16/2019] [Indexed: 02/07/2023]
Abstract
Human pluripotent stem cells (hPSCs) offer a multifaceted platform to study cardiac developmental biology, understand disease mechanisms, and develop novel therapies. Remarkable progress over the last two decades has led to methods to obtain highly pure hPSC-derived cardiomyocytes (hPSC-CMs) with reasonable ease and scalability. Nevertheless, a major bottleneck for the translational application of hPSC-CMs is their immature phenotype, resembling that of early fetal cardiomyocytes. Overall, bona fide maturation of hPSC-CMs represents one of the most significant goals facing the field today. Developmental biology studies have been pivotal in understanding the mechanisms to differentiate hPSC-CMs. Similarly, evaluation of developmental cues such as electrical and mechanical activities or neurohormonal and metabolic stimulations revealed the importance of these pathways in cardiomyocyte physiological maturation. Those signals cooperate and dictate the size and the performance of the developing heart. Likewise, this orchestra of stimuli is important in promoting hPSC-CM maturation, as demonstrated by current in vitro maturation approaches. Different shades of adult-like phenotype are achieved by prolonging the time in culture, electromechanical stimulation, patterned substrates, microRNA manipulation, neurohormonal or metabolic stimulation, and generation of human-engineered heart tissue (hEHT). However, mirroring this extremely dynamic environment is challenging, and reproducibility and scalability of these approaches represent the major obstacles for an efficient production of mature hPSC-CMs. For this reason, understanding the pattern behind the mechanisms elicited during the late gestational and early postnatal stages not only will provide new insights into postnatal development but also potentially offer new scalable and efficient approaches to mature hPSC-CMs.
Collapse
|
14
|
Augmentation of myocardial I f dysregulates calcium homeostasis and causes adverse cardiac remodeling. Nat Commun 2019; 10:3295. [PMID: 31337768 PMCID: PMC6650438 DOI: 10.1038/s41467-019-11261-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 06/28/2019] [Indexed: 01/18/2023] Open
Abstract
HCN channels underlie the depolarizing funny current (If) that contributes importantly to cardiac pacemaking. If is upregulated in failing and infarcted hearts, but its implication in disease mechanisms remained unresolved. We generated transgenic mice (HCN4tg/wt) to assess functional consequences of HCN4 overexpression-mediated If increase in cardiomyocytes to levels observed in human heart failure. HCN4tg/wt animals exhibit a dilated cardiomyopathy phenotype with increased cellular arrhythmogenicity but unchanged heart rate and conduction parameters. If augmentation induces a diastolic Na+ influx shifting the Na+/Ca2+ exchanger equilibrium towards ‘reverse mode’ leading to increased [Ca2+]i. Changed Ca2+ homeostasis results in significantly higher systolic [Ca2+]i transients and stimulates apoptosis. Pharmacological inhibition of If prevents the rise of [Ca2+]i and protects from ventricular remodeling. Here we report that augmented myocardial If alters intracellular Ca2+ homeostasis leading to structural cardiac changes and increased arrhythmogenicity. Inhibition of myocardial Ifper se may constitute a therapeutic mechanism to prevent cardiomyopathy. The depolarizing funny current contributing to cardiac pacemaking is upregulated in the myocardium of failing and infarcted hearts, but whether the current is implied in disease mechanisms is unclear. Here the authors generate HCN4 transgenic mice and show that upregulation of funny current to the levels observed in human heart failure alters calcium homeostasis leading to cardiac remodelling and arrhythmia.
Collapse
|
15
|
Darche FF, Rivinius R, Köllensperger E, Leimer U, Germann G, Seckinger A, Hose D, Schröter J, Bruehl C, Draguhn A, Gabriel R, Schmidt M, Koenen M, Thomas D, Katus HA, Schweizer PA. Pacemaker cell characteristics of differentiated and HCN4-transduced human mesenchymal stem cells. Life Sci 2019; 232:116620. [PMID: 31291594 DOI: 10.1016/j.lfs.2019.116620] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 06/21/2019] [Accepted: 06/29/2019] [Indexed: 12/13/2022]
Abstract
AIMS Cell-based biological pacemakers aim to overcome limitations and side effects of electronic pacemaker devices. We here developed and tested different approaches to achieve nodal-type differentiation using human adipose- and bone marrow-derived mesenchymal stem cells (haMSC, hbMSC). MAIN METHODS haMSC and hbMSC were differentiated using customized protocols. Quantitative RT-PCR was applied for transcriptional pacemaker-gene profiling. Protein membrane expression was analyzed by immunocytochemistry. Pacemaker current (If) was studied in haMSC with and without lentiviral HCN4-transduction using patch clamp recordings. Functional characteristics were evaluated by co-culturing with neonatal rat ventricular myocytes (NRVM). KEY FINDINGS Culture media-based differentiation for two weeks generated cells with abundant transcription of ion channel genes (Cav1.2, NCX1), transcription factors (TBX3, TBX18, SHOX2) and connexins (Cx31.9 and Cx45) characteristic for cardiac pacemaker tissue, but lack adequate HCN transcription. haMSC-derived cells revealed transcript levels, which were closer related to sinoatrial nodal cells than hbMSC-derived cells. To substitute for the lack of If, we performed lentiviral HCN4-transduction of haMSC resulting in stable If. Co-culturing with NRVM demonstrated that differentiated haMSC expressing HCN4 showed earlier onset of spontaneous contractions and higher beating regularity, synchrony and rate compared to co-cultures with non-HCN4-transduced haMSC or HCN4-transduced, non-differentiated haMSC. Confocal imaging indicated increased membrane expression of cardiac gap junctional proteins in differentiated haMSC. SIGNIFICANCE By differentiation haMSC, rather than hbMSC attain properties favorable for cardiac pacemaking. In combination with lentiviral HCN4-transduction, a cellular phenotype was generated that sustainably controls and stabilizes rate in co-culture with NRVM.
Collapse
Affiliation(s)
- Fabrice F Darche
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany
| | - Rasmus Rivinius
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany
| | - Eva Köllensperger
- ETHIANUM Klinik Heidelberg, Voßstraße 6, D-69115 Heidelberg, Germany
| | - Uwe Leimer
- ETHIANUM Klinik Heidelberg, Voßstraße 6, D-69115 Heidelberg, Germany
| | - Günter Germann
- ETHIANUM Klinik Heidelberg, Voßstraße 6, D-69115 Heidelberg, Germany
| | - Anja Seckinger
- Department of Hematology, Oncology and Rheumatology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany
| | - Dirk Hose
- Department of Hematology, Oncology and Rheumatology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany
| | - Julian Schröter
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany
| | - Claus Bruehl
- Institute for Physiology and Pathophysiology, University of Heidelberg, INF 326, D-69120 Heidelberg, Germany
| | - Andreas Draguhn
- Institute for Physiology and Pathophysiology, University of Heidelberg, INF 326, D-69120 Heidelberg, Germany
| | - Richard Gabriel
- Molecular and Gene Therapy, National Center for Tumor Diseases (NCT) Heidelberg, INF 460, D-69120 Heidelberg, Germany
| | - Manfred Schmidt
- Molecular and Gene Therapy, National Center for Tumor Diseases (NCT) Heidelberg, INF 460, D-69120 Heidelberg, Germany
| | - Michael Koenen
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany; Department of Molecular Neurobiology, Max-Planck-Institute for Medical Research, Jahnstrasse 29, D-69120 Heidelberg, Germany
| | - Dierk Thomas
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany; DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, INF 410, D-69120 Heidelberg, Germany
| | - Hugo A Katus
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany; DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, INF 410, D-69120 Heidelberg, Germany
| | - Patrick A Schweizer
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120 Heidelberg, Germany; DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, INF 410, D-69120 Heidelberg, Germany.
| |
Collapse
|
16
|
Kannan S, Kwon C. Regulation of cardiomyocyte maturation during critical perinatal window. J Physiol 2019; 598:2941-2956. [PMID: 30571853 DOI: 10.1113/jp276754] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 11/23/2018] [Indexed: 12/13/2022] Open
Abstract
A primary limitation in the use of pluripotent stem cell-derived cardiomyocytes (PSC-CMs) for both patient health and scientific investigation is the failure of these cells to achieve full functional maturity. In vivo, cardiomyocytes undergo numerous adaptive structural, functional and metabolic changes during maturation. By contrast, PSC-CMs fail to fully undergo these developmental processes, instead remaining arrested at an embryonic stage of maturation. There is thus a significant need to understand the biological processes underlying proper CM maturation in vivo. Here, we discuss what is known regarding the initiation and coordination of CM maturation. We postulate that there is a critical perinatal window, ranging from embryonic day 18.5 to postnatal day 14 in mice, in which the maturation process is exquisitely sensitive to perturbation. While the initiation mechanisms of this process are unknown, it is increasingly clear that maturation proceeds through interconnected regulatory circuits that feed into one another to coordinate concomitant structural, functional and metabolic CM maturation. We highlight PGC1α, SRF and the MEF2 family as transcription factors that may potentially mediate this cross-talk. We lastly discuss several emerging technologies that will facilitate future studies into the mechanisms of CM maturation. Further study will not only produce a better understanding of its key processes, but provide practical insights into developing a robust strategy to produce mature PSC-CMs.
Collapse
Affiliation(s)
- Suraj Kannan
- Johns Hopkins University School of Medicine, 733 North Broadway, Baltimore, MD, 21205, USA
| | - Chulan Kwon
- Johns Hopkins University School of Medicine, 733 North Broadway, Baltimore, MD, 21205, USA
| |
Collapse
|
17
|
Chevalier M, Vermij SH, Wyler K, Gillet L, Keller I, Abriel H. Transcriptomic analyses of murine ventricular cardiomyocytes. Sci Data 2018; 5:180170. [PMID: 30129933 PMCID: PMC6103258 DOI: 10.1038/sdata.2018.170] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 06/14/2018] [Indexed: 12/27/2022] Open
Abstract
Mice are used universally as model organisms for studying heart physiology, and a plethora of genetically modified mouse models exist to study cardiac disease. Transcriptomic data for whole-heart tissue are available, but not yet for isolated ventricular cardiomyocytes. Our lab therefore collected comprehensive RNA-seq data from wildtype murine ventricular cardiomyocytes as well as from knockout models of the ion channel regulators CASK, dystrophin, and SAP97. We also elucidate ion channel expression from wild-type cells to help forward the debate about which ion channels are expressed in cardiomyocytes. Researchers studying the heart, and especially cardiac arrhythmias, may benefit from these cardiomyocyte-specific transcriptomic data to assess expression of genes of interest.
Collapse
Affiliation(s)
- Morgan Chevalier
- Ion Channels and Channelopathies Laboratory, Institute for Biochemistry and Molecular Medicine, University of Bern, 3012 Bern, Switzerland
| | - Sarah H Vermij
- Ion Channels and Channelopathies Laboratory, Institute for Biochemistry and Molecular Medicine, University of Bern, 3012 Bern, Switzerland
| | - Kurt Wyler
- Interfaculty Bioinformatics Unit and Swiss Institute of Bioinformatics, University of Bern, 3012 Bern, Switzerland
| | - Ludovic Gillet
- Pain Center, Department of Anesthesiology, University Hospital Center (CHUV) and Faculty of Biology and Medicine (FBM), University of Lausanne, 1011 Lausanne, Switzerland.,Department of Fundamental Neurosciences, Faculty of Biology and Medicine (FBM), University of Lausanne, 1005 Lausanne, Switzerland
| | - Irene Keller
- Department for BioMedical Research and Swiss Institute of Bioinformatics, University of Bern, 3007 Bern, Switzerland
| | - Hugues Abriel
- Ion Channels and Channelopathies Laboratory, Institute for Biochemistry and Molecular Medicine, University of Bern, 3012 Bern, Switzerland
| |
Collapse
|
18
|
Jackman CP, Ganapathi AM, Asfour H, Qian Y, Allen BW, Li Y, Bursac N. Engineered cardiac tissue patch maintains structural and electrical properties after epicardial implantation. Biomaterials 2018; 159:48-58. [PMID: 29309993 DOI: 10.1016/j.biomaterials.2018.01.002] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 12/17/2017] [Accepted: 01/01/2018] [Indexed: 12/22/2022]
Abstract
Functional cardiac tissue engineering holds promise as a candidate therapy for myocardial infarction and heart failure. Generation of "strong-contracting and fast-conducting" cardiac tissue patches capable of electromechanical coupling with host myocardium could allow efficient improvement of heart function without increased arrhythmogenic risks. Towards that goal, we engineered highly functional 1 cm × 1 cm cardiac tissue patches made of neonatal rat ventricular cells which after 2 weeks of culture exhibited force of contraction of 18.0 ± 1.4 mN, conduction velocity (CV) of 32.3 ± 1.8 cm/s, and sustained chronic activation when paced at rates as high as 8.7 ± 0.8 Hz. Patches transduced with genetically-encoded calcium indicator (GCaMP6) were implanted onto adult rat ventricles and after 4-6 weeks assessed for action potential conduction and electrical integration by two-camera optical mapping of GCaMP6-reported Ca2+ transients in the patch and RH237-reported action potentials in the recipient heart. Of the 13 implanted patches, 11 (85%) engrafted, maintained structural integrity, and conducted action potentials with average CVs and Ca2+ transient durations comparable to those before implantation. Despite preserved graft electrical properties, no anterograde or retrograde conduction could be induced between the patch and host cardiomyocytes, indicating lack of electrical integration. Electrical properties of the underlying myocardium were not changed by the engrafted patch. From immunostaining analyses, implanted patches were highly vascularized and expressed abundant electromechanical junctions, but remained separated from the epicardium by a non-myocyte layer. In summary, our studies demonstrate generation of highly functional cardiac tissue patches that can robustly engraft on the epicardial surface, vascularize, and maintain electrical function, but do not couple with host tissue. The lack of graft-host electrical integration is therefore a critical obstacle to development of efficient tissue engineering therapies for heart repair.
Collapse
Affiliation(s)
| | - Asvin M Ganapathi
- Duke University Medical Center, Department of General Surgery, Durham, NC, USA
| | - Huda Asfour
- Duke University, Department of Biomedical Engineering, Durham, NC, USA
| | - Ying Qian
- Duke University, Department of Biomedical Engineering, Durham, NC, USA
| | - Brian W Allen
- Duke University, Department of Biomedical Engineering, Durham, NC, USA
| | - Yanzhen Li
- Duke University, Department of Biomedical Engineering, Durham, NC, USA
| | - Nenad Bursac
- Duke University, Department of Biomedical Engineering, Durham, NC, USA.
| |
Collapse
|
19
|
Salari S, Silverå Ejneby M, Brask J, Elinder F. Isopimaric acid - a multi-targeting ion channel modulator reducing excitability and arrhythmicity in a spontaneously beating mouse atrial cell line. Acta Physiol (Oxf) 2018; 222. [PMID: 28514017 DOI: 10.1111/apha.12895] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 03/08/2017] [Accepted: 05/12/2017] [Indexed: 11/28/2022]
Abstract
AIM Atrial fibrillation is the most common persistent cardiac arrhythmia, and it is not well controlled by present drugs. Because some resin acids open voltage-gated potassium channels and reduce neuronal excitability, we explored the effects of the resin acid isopimaric acid (IPA) on action potentials and ion currents in cardiomyocytes. METHODS Spontaneously beating mouse atrial HL-1 cells were investigated with the whole-cell patch-clamp technique. RESULTS 1-25 μmol L-1 IPA reduced the action potential frequency by up to 50%. The effect of IPA on six different voltage-gated ion channels was investigated; most voltage-dependent parameters of ion channel gating were shifted in the negative direction along the voltage axis, consistent with a hypothesis that a lipophilic and negatively charged compound binds to the lipid membrane close to the positively charged voltage sensor of the ion channels. The major finding was that IPA inactivated sodium channels and L- and T-type calcium channels and activated the rapidly activating potassium channel and the transient outward potassium channel. Computer simulations of IPA effects on all of the ion currents were consistent with a reduced excitability, and they also showed that effects on the Na channel played the largest role to reduce the action potential frequency. Finally, induced arrhythmia in the HL-1 cells was reversed by IPA. CONCLUSION Low concentrations of IPA reduced the action potential frequency and restored regular firing by altering the voltage dependencies of several voltage-gated ion channels. These findings can form the basis for a new pharmacological strategy to treat atrial fibrillation.
Collapse
Affiliation(s)
- S. Salari
- Department of Clinical and Experimental Medicine; Linköping University; Linköping Sweden
| | - M. Silverå Ejneby
- Department of Clinical and Experimental Medicine; Linköping University; Linköping Sweden
| | - J. Brask
- Department of Clinical and Experimental Medicine; Linköping University; Linköping Sweden
| | - F. Elinder
- Department of Clinical and Experimental Medicine; Linköping University; Linköping Sweden
| |
Collapse
|
20
|
Antolic A, Wood CE, Keller-Wood M. Use of radiotelemetry to assess perinatal cardiac function in the ovine fetus and newborn. Am J Physiol Regul Integr Comp Physiol 2017; 313:R660-R668. [PMID: 28855176 PMCID: PMC5814690 DOI: 10.1152/ajpregu.00078.2017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 07/26/2017] [Accepted: 08/23/2017] [Indexed: 12/11/2022]
Abstract
The late gestation fetal ECG (fECG) has traditionally been difficult to characterize due to the low fECG signal relative to high maternal noise. Although new technologies have improved the feasibility of its acquisition and separation, little is known about its development in late gestation, a period in which the fetal heart undergoes extensive maturational changes. Here, we describe a method for the chronic implantation of radiotelemetry devices into late gestation ovine fetuses to characterize parameters of the fECG following surgery, throughout late gestation, and in the perinatal period. We found no significant changes in mean aortic pressure (MAP), heart rate (HR), or ECG in the 5 days following implantation; however, HR decreased in the first 24 h following the end of surgery, with associated increases in RR, PR, and QRS intervals. Over the last 14 days of fetal life, fetal MAP significantly increased, and HR significantly decreased, as expected. MAP and HR increased as labor progressed. Although there were no significant changes over time in the ECG during late gestation, the duration of the PR interval initially decreased and then increased as birth approached. These results indicate that although critical maturational changes occur in the late gestation fetal myocardium, the mechanisms that control the cardiac conduction are relatively mature in late gestation. The study demonstrates that radiotelemetry can be successfully used to assess fetal cardiac function, in particular conduction, through the process of labor and delivery, and may therefore be a useful tool for study of peripartum cardiac events.
Collapse
Affiliation(s)
- A Antolic
- Department of Pharmacodynamics, University of Florida, Gainesville, Florida;
| | - C E Wood
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida; and
| | - M Keller-Wood
- Department of Pharmacodynamics, University of Florida, Gainesville, Florida
| |
Collapse
|
21
|
Schweizer PA, Darche FF, Ullrich ND, Geschwill P, Greber B, Rivinius R, Seyler C, Müller-Decker K, Draguhn A, Utikal J, Koenen M, Katus HA, Thomas D. Subtype-specific differentiation of cardiac pacemaker cell clusters from human induced pluripotent stem cells. Stem Cell Res Ther 2017; 8:229. [PMID: 29037217 PMCID: PMC5644063 DOI: 10.1186/s13287-017-0681-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2017] [Revised: 09/07/2017] [Accepted: 09/25/2017] [Indexed: 12/11/2022] Open
Abstract
Background Human induced pluripotent stem cells (hiPSC) harbor the potential to differentiate into diverse cardiac cell types. Previous experimental efforts were primarily directed at the generation of hiPSC-derived cells with ventricular cardiomyocyte characteristics. Aiming at a straightforward approach for pacemaker cell modeling and replacement, we sought to selectively differentiate cells with nodal-type properties. Methods hiPSC were differentiated into spontaneously beating clusters by co-culturing with visceral endoderm-like cells in a serum-free medium. Subsequent culturing in a specified fetal bovine serum (FBS)-enriched cell medium produced a pacemaker-type phenotype that was studied in detail using quantitative real-time polymerase chain reaction (qRT-PCR), immunocytochemistry, and patch-clamp electrophysiology. Further investigations comprised pharmacological stimulations and co-culturing with neonatal cardiomyocytes. Results hiPSC co-cultured in a serum-free medium with the visceral endoderm-like cell line END-2 produced spontaneously beating clusters after 10–12 days of culture. The pacemaker-specific genes HCN4, TBX3, and TBX18 were abundantly expressed at this early developmental stage, while levels of sarcomeric gene products remained low. We observed that working-type cardiomyogenic differentiation can be suppressed by transfer of early clusters into a FBS-enriched cell medium immediately after beating onset. After 6 weeks under these conditions, sinoatrial node (SAN) hallmark genes remained at high levels, while working-type myocardial transcripts (NKX2.5, TBX5) were low. Clusters were characterized by regular activity and robust beating rates (70–90 beats/min) and were triggered by spontaneous Ca2+ transients recapitulating calcium clock properties of genuine pacemaker cells. They were responsive to adrenergic/cholinergic stimulation and able to pace neonatal rat ventricular myocytes in co-culture experiments. Action potential (AP) measurements of cells individualized from clusters exhibited nodal-type (63.4%) and atrial-type (36.6%) AP morphologies, while ventricular AP configurations were not observed. Conclusion We provide a novel culture media-based, transgene-free approach for targeted generation of hiPSC-derived pacemaker-type cells that grow in clusters and offer the potential for disease modeling, drug testing, and individualized cell-based replacement therapy of the SAN. Electronic supplementary material The online version of this article (doi:10.1186/s13287-017-0681-4) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Patrick A Schweizer
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120, Heidelberg, Germany. .,DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, INF 410, D-69120, Heidelberg, Germany.
| | - Fabrice F Darche
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120, Heidelberg, Germany
| | - Nina D Ullrich
- DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, INF 410, D-69120, Heidelberg, Germany.,Institute of Physiology and Pathophysiology, Division of Cardiovascular Physiology, Heidelberg University, INF 326, D-69120, Heidelberg, Germany
| | - Pascal Geschwill
- Institute of Physiology and Pathophysiology, Division of Neuro- and Sensory Physiology, Heidelberg University, INF 326, D-69120, Heidelberg, Germany
| | - Boris Greber
- Department of Cell and Developmental Biology, Max-Planck-Institute for Molecular Biomedicine, Röntgenstrasse, 20, D-48149, Münster, Germany
| | - Rasmus Rivinius
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120, Heidelberg, Germany
| | - Claudia Seyler
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, INF 410, D-69120, Heidelberg, Germany
| | - Karin Müller-Decker
- Unit Tumor Models, German Cancer Research Center (DKFZ), Heidelberg, INF 280, D-69120, Heidelberg, Germany
| | - Andreas Draguhn
- Institute of Physiology and Pathophysiology, Division of Neuro- and Sensory Physiology, Heidelberg University, INF 326, D-69120, Heidelberg, Germany
| | - Jochen Utikal
- DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, INF 410, D-69120, Heidelberg, Germany.,Dermato-Oncology (G300), German Cancer Research Center (DKFZ), Heidelberg, INF 280, D-69120, Heidelberg, Germany.,Department of Dermatology, Venereology and Allergology, University Medical Center Mannheim, Ruprecht-Karl University of Heidelberg, Theodor-Kutzer-Ufer 1-3, D-68167, Mannheim, Germany
| | - Michael Koenen
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120, Heidelberg, Germany.,Department of Molecular Neurobiology, Max-Planck-Institute for Medical Research, Jahnstrasse 29, D-69120, Heidelberg, Germany
| | - Hugo A Katus
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, INF 410, D-69120, Heidelberg, Germany
| | - Dierk Thomas
- Department of Cardiology, Medical University Hospital Heidelberg, INF 410, D-69120, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, INF 410, D-69120, Heidelberg, Germany
| |
Collapse
|
22
|
Pedernera E, Gómora MJ, Meneses I, De Ita M, Méndez C. Androgen receptor is expressed in mouse cardiomyocytes at prenatal and early postnatal developmental stages. BMC PHYSIOLOGY 2017; 17:7. [PMID: 28806941 PMCID: PMC5557468 DOI: 10.1186/s12899-017-0033-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 08/03/2017] [Indexed: 11/10/2022]
Abstract
Background Previous studies show that androgens are involved in hypertrophy and excitability of cardiomyocytes and that their effects are mediated through their receptor. The aim of this study was to evaluate the presence of androgen receptor (AR) in mouse heart during prenatal and early postnatal stages. Results The expression of AR and related genes, alpha myosin heavy chain -Myh6-, beta myosin heavy chain -Myh7- and atrial natriuretic factor –Nppa- was simultaneously evaluated by semiquantitative RT-PCR. AR was also detected by immunohistochemistry. Androgen receptor mRNA was detected in hearts from 10.5 days post coitum to 16 postnatal days. A higher expression of AR mRNA in atria compared to ventricles was observed in neonatal mouse. A positive correlation between mRNA levels of AR and Nppa was observed in mouse heart at early postnatal development. Androgen receptor expression is similar in males and females during cardiac development. Finally, androgen receptor protein was observed by immunohistochemistry in myocardial cells of atria and ventricles from 12.5 days onwards and restricted after 16.5 days post-coitum to nuclei of cardiomyocytes. Conclusion Present results provide evidence that androgen receptor is expressed from prenatal stages in mouse heart, supporting the proposition that androgens could be involved in mammalian heart development.
Collapse
Affiliation(s)
- Enrique Pedernera
- Facultad de Medicina, Edificio E, Universidad Nacional Autónoma de México, Av. Universidad #3000, Coyoacán, 04510, Cd. de México, CP, Mexico
| | - María José Gómora
- Facultad de Medicina, Edificio E, Universidad Nacional Autónoma de México, Av. Universidad #3000, Coyoacán, 04510, Cd. de México, CP, Mexico
| | - Iván Meneses
- Facultad de Medicina, Edificio E, Universidad Nacional Autónoma de México, Av. Universidad #3000, Coyoacán, 04510, Cd. de México, CP, Mexico
| | - Marlon De Ita
- Facultad de Medicina, Edificio E, Universidad Nacional Autónoma de México, Av. Universidad #3000, Coyoacán, 04510, Cd. de México, CP, Mexico
| | - Carmen Méndez
- Facultad de Medicina, Edificio E, Universidad Nacional Autónoma de México, Av. Universidad #3000, Coyoacán, 04510, Cd. de México, CP, Mexico.
| |
Collapse
|
23
|
Coppini R, Mazzoni L, Ferrantini C, Gentile F, Pioner JM, Laurino A, Santini L, Bargelli V, Rotellini M, Bartolucci G, Crocini C, Sacconi L, Tesi C, Belardinelli L, Tardiff J, Mugelli A, Olivotto I, Cerbai E, Poggesi C. Ranolazine Prevents Phenotype Development in a Mouse Model of Hypertrophic Cardiomyopathy. Circ Heart Fail 2017; 10:CIRCHEARTFAILURE.116.003565. [PMID: 28255011 DOI: 10.1161/circheartfailure.116.003565] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 01/30/2017] [Indexed: 01/04/2023]
Abstract
BACKGROUND Current therapies are ineffective in preventing the development of cardiac phenotype in young carriers of mutations associated with hypertrophic cardiomyopathy (HCM). Ranolazine, a late Na+ current blocker, reduced the electromechanical dysfunction of human HCM myocardium in vitro. METHODS AND RESULTS To test whether long-term treatment prevents cardiomyopathy in vivo, transgenic mice harboring the R92Q troponin-T mutation and wild-type littermates received an oral lifelong treatment with ranolazine and were compared with age-matched vehicle-treated animals. In 12-months-old male R92Q mice, ranolazine at therapeutic plasma concentrations prevented the development of HCM-related cardiac phenotype, including thickening of the interventricular septum, left ventricular volume reduction, left ventricular hypercontractility, diastolic dysfunction, left-atrial enlargement and left ventricular fibrosis, as evaluated in vivo using echocardiography and magnetic resonance. Left ventricular cardiomyocytes from vehicle-treated R92Q mice showed marked excitation-contraction coupling abnormalities, including increased diastolic [Ca2+] and Ca2+ waves, whereas cells from treated mutants were undistinguishable from those from wild-type mice. Intact trabeculae from vehicle-treated mutants displayed inotropic insufficiency, increased diastolic tension, and premature contractions; ranolazine treatment counteracted the development of myocardial mechanical abnormalities. In mutant myocytes, ranolazine inhibited the enhanced late Na+ current and reduced intracellular [Na+] and diastolic [Ca2+], ultimately preventing the pathological increase of calmodulin kinase activity in treated mice. CONCLUSIONS Owing to the sustained reduction of intracellular Ca2+ and calmodulin kinase activity, ranolazine prevented the development of morphological and functional cardiac phenotype in mice carrying a clinically relevant HCM-related mutation. Pharmacological inhibitors of late Na+ current are promising candidates for an early preventive therapy in young phenotype-negative subjects carrying high-risk HCM-related mutations.
Collapse
Affiliation(s)
- Raffaele Coppini
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.).
| | - Luca Mazzoni
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Cecilia Ferrantini
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Francesca Gentile
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Josè Manuel Pioner
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Annunziatina Laurino
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Lorenzo Santini
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Valentina Bargelli
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Matteo Rotellini
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Gianluca Bartolucci
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Claudia Crocini
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Leonardo Sacconi
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Chiara Tesi
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Luiz Belardinelli
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Jil Tardiff
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Alessandro Mugelli
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Iacopo Olivotto
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Elisabetta Cerbai
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| | - Corrado Poggesi
- From the Department NeuroFarBa (R.C., L.M., T.L., L. Santini, V.B., G.B., A.M., E.C.) and Department of Experimental and Clinical Medicine (C.F., F.G., J.M.P., C.T., C.P.), University of Florence, Italy; European Laboratory for Non-linear Spectroscopy (LENS), University of Florence & National Institute of Optics (INO-CNR), Sesto Fiorentino, Italy (C.C., L. Sacconi); Gilead Sciences Inc., Foster City, CA (L.B.); Department of Cellular and Molecular Medicine University of Arizona at Tucson, USA (J.T.); and Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (M.R., I.O.)
| |
Collapse
|
24
|
Barbuti A, Benzoni P, Campostrini G, Dell'Era P. Human derived cardiomyocytes: A decade of knowledge after the discovery of induced pluripotent stem cells. Dev Dyn 2016; 245:1145-1158. [DOI: 10.1002/dvdy.24455] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 05/05/2016] [Accepted: 05/05/2016] [Indexed: 12/27/2022] Open
Affiliation(s)
- Andrea Barbuti
- Department of Biosciences; Università degli Studi di Milano; Milan Italy
| | - Patrizia Benzoni
- Department of Biosciences; Università degli Studi di Milano; Milan Italy
| | - Giulia Campostrini
- Department of Biosciences; Università degli Studi di Milano; Milan Italy
| | - Patrizia Dell'Era
- Cellular Fate Reprogramming Unit, Department of Molecular and Translational Medicine; Università degli Studi di Brescia; Brescia Italy
| |
Collapse
|
25
|
Li W, Zheng NZ, Yuan Q, Xu K, Yang F, Gu L, Zheng GY, Luo GJ, Fan C, Ji GJ, Zhang B, Cao H, Tian XL. NFAT5-mediated CACNA1C expression is critical for cardiac electrophysiological development and maturation. J Mol Med (Berl) 2016; 94:993-1002. [PMID: 27368804 DOI: 10.1007/s00109-016-1444-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 06/18/2016] [Accepted: 06/24/2016] [Indexed: 01/30/2023]
Abstract
UNLABELLED Entry of calcium into cardiomyocyte via L-type calcium channel (LTCC) is fundamental to cardiac contraction. CACNA1C, a type of LTCC and a hallmark of a matured ventricular myocyte, is developmentally regulated. Here, we identified 138 potential transcription factors by a comparative genomic study on 5-kb promoter regions of CACNA1C gene across eight vertebrate species, and showed that six factors were developmentally regulated with the expression of Cacna1c in mouse P19cl6 in vitro cardiomyocyte differentiation model. We further demonstrated that the nuclear factor of activated T cells 5 (Nfat5) bound to a consensus sequence TGGAAGCGTTC and activated the transcription of Cacna1c. The siRNA-mediated knockdown of Nfat5 suppressed the expression of Cacna1c and decreased L-type calcium current in mouse neonatal cardiomyocytes. Furthermore, morpholino-mediated knockdown of nfat5 in zebrafish prohibited the expression of cacna1c and resulted in a non-contractile ventricle, while over-expression of either cacna1c or nfat5 rescued this impaired phenotype. Thus, NFAT5-mediated expression of CACNA1C is evolutionarily conserved and critical for cardiac electrophysiological development and maturation of cardiomyocyte. KEY MESSAGE Nfat5 binds to a consensus sequence TGGAAGCGTTC in the promoter of Cacna1c. Nfat5 activates the transcription of Cacna1c. Nfat5 knockdown suppresses Cacna1c expression, decreases L-type calcium current, and results in non-beating ventricle. NFAT5-mediated expression of CACNA1C is evolutionarily conserved. NFAT5-mediated CACNA1C expression is critical for cardiac electrophysiological development and maturation.
Collapse
Affiliation(s)
- Wei Li
- Department of Human Population Genetics, Institute of Molecular Medicine, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
| | - Nai-Zhong Zheng
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
| | - Qi Yuan
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing, 100101, China
| | - Ke Xu
- Department of Human Population Genetics, Institute of Molecular Medicine, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
| | - Fan Yang
- Department of Human Population Genetics, Institute of Molecular Medicine, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
| | - Lei Gu
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing, 100101, China
| | - Gu-Yan Zheng
- Department of Human Population Genetics, Institute of Molecular Medicine, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
| | - Guo-Jie Luo
- School of Electronics Engineering and Computer Science, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
| | - Chun Fan
- Department of Biomedical Engineering, Lerner Research Institute, The Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH, 44195, USA
| | - Guang-Ju Ji
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing, 100101, China
| | - Bo Zhang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, 5 Yiheyuan Road, Beijing, 100871, China
| | - Huiqing Cao
- Department of Human Population Genetics, Institute of Molecular Medicine, Peking University, 5 Yiheyuan Road, Beijing, 100871, China.
| | - Xiao-Li Tian
- Department of Human Population Genetics, Institute of Molecular Medicine, Peking University, 5 Yiheyuan Road, Beijing, 100871, China.
| |
Collapse
|
26
|
Vaidyanathan R, Markandeya YS, Kamp TJ, Makielski JC, January CT, Eckhardt LL. IK1-enhanced human-induced pluripotent stem cell-derived cardiomyocytes: an improved cardiomyocyte model to investigate inherited arrhythmia syndromes. Am J Physiol Heart Circ Physiol 2016; 310:H1611-21. [PMID: 27059077 DOI: 10.1152/ajpheart.00481.2015] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 04/01/2016] [Indexed: 01/05/2023]
Abstract
Currently available induced pluripotent stem cell-derived cardiomyocytes (iPS-CMs) do not ideally model cellular mechanisms of human arrhythmic disease due to lack of a mature action potential (AP) phenotype. In this study, we create and characterize iPS-CMs with an electrically mature AP induced by potassium inward rectifier (IK1) enhancement. The advantages of IK1-enhanced iPS-CMs include the absence of spontaneous beating, stable resting membrane potentials at approximately -80 mV and capability for electrical pacing. Compared with unenhanced, IK1-enhanced iPS-CMs calcium transient amplitudes were larger (P < 0.05) with a typical staircase pattern. IK1-enhanced iPS-CMs demonstrated a twofold increase in cell size and membrane capacitance and increased DNA synthesis compared with control iPS-CMs (P < 0.05). Furthermore, IK1-enhanced iPS-CMs expressing the F97C-CAV3 long QT9 mutation compared with wild-type CAV3 demonstrated an increase in AP duration and late sodium current. IK1-enhanced iPS-CMs represent a more mature cardiomyocyte model to study arrhythmia mechanisms.
Collapse
Affiliation(s)
- Ravi Vaidyanathan
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin, Madison, Wisconsin
| | - Yogananda S Markandeya
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin, Madison, Wisconsin
| | - Timothy J Kamp
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin, Madison, Wisconsin
| | - Jonathan C Makielski
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin, Madison, Wisconsin
| | - Craig T January
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin, Madison, Wisconsin
| | - Lee L Eckhardt
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin, Madison, Wisconsin
| |
Collapse
|
27
|
Ladd AN. New Insights Into the Role of RNA-Binding Proteins in the Regulation of Heart Development. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 324:125-85. [PMID: 27017008 DOI: 10.1016/bs.ircmb.2015.12.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The regulation of gene expression during development takes place both at the transcriptional and posttranscriptional levels. RNA-binding proteins (RBPs) regulate pre-mRNA processing, mRNA localization, stability, and translation. Many RBPs are expressed in the heart and have been implicated in heart development, function, or disease. This chapter will review the current knowledge about RBPs in the developing heart, focusing on those that regulate posttranscriptional gene expression. The involvement of RBPs at each stage of heart development will be considered in turn, including the establishment of specific cardiac cell types and formation of the primitive heart tube, cardiac morphogenesis, and postnatal maturation and aging. The contributions of RBPs to cardiac birth defects and heart disease will also be considered in these contexts. Finally, the interplay between RBPs and other regulatory factors in the developing heart, such as transcription factors and miRNAs, will be discussed.
Collapse
Affiliation(s)
- A N Ladd
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States of America.
| |
Collapse
|
28
|
Glasscock E, Voigt N, McCauley MD, Sun Q, Li N, Chiang DY, Zhou XB, Molina CE, Thomas D, Schmidt C, Skapura DG, Noebels JL, Dobrev D, Wehrens XHT. Expression and function of Kv1.1 potassium channels in human atria from patients with atrial fibrillation. Basic Res Cardiol 2015; 110:505. [PMID: 26162324 DOI: 10.1007/s00395-015-0505-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 07/02/2015] [Accepted: 07/03/2015] [Indexed: 11/24/2022]
Abstract
Voltage-gated Kv1.1 channels encoded by the Kcna1 gene are traditionally regarded as being neural-specific with no known expression or intrinsic functional role in the heart. However, recent studies in mice reveal low-level Kv1.1 expression in heart and cardiac abnormalities associated with Kv1.1-deficiency suggesting that the channel may have a previously unrecognized cardiac role. Therefore, this study tests the hypothesis that Kv1.1 channels are associated with arrhythmogenesis and contribute to intrinsic cardiac function. In intra-atrial burst pacing experiments, Kcna1-null mice exhibited increased susceptibility to atrial fibrillation (AF). The atria of Kcna1-null mice showed minimal Kv1 family ion channel remodeling and fibrosis as measured by qRT-PCR and Masson's trichrome histology, respectively. Using RT-PCR, immunocytochemistry, and immunoblotting, KCNA1 mRNA and protein were detected in isolated mouse cardiomyocytes and human atria for the first time. Patients with chronic AF (cAF) showed no changes in KCNA1 mRNA levels relative to controls; however, they exhibited increases in atrial Kv1.1 protein levels, not seen in paroxysmal AF patients. Patch-clamp recordings of isolated human atrial myocytes revealed significant dendrotoxin-K (DTX-K)-sensitive outward current components that were significantly increased in cAF patients, reflecting a contribution by Kv1.1 channels. The concomitant increases in Kv1.1 protein and DTX-K-sensitive currents in atria of cAF patients suggest that the channel contributes to the pathological mechanisms of persistent AF. These findings provide evidence of an intrinsic cardiac role of Kv1.1 channels and indicate that they may contribute to atrial repolarization and AF susceptibility.
Collapse
Affiliation(s)
- Edward Glasscock
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, 1501 Kings Highway, P.O. Box 33932, Shreveport, LA, 71130-393, USA,
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Dasgupta T, Coram RJ, Stillwagon SJ, Ladd AN. Gene Expression Analyses during Spontaneous Reversal of Cardiomyopathy in Mice with Repressed Nuclear CUG-BP, Elav-Like Family (CELF) Activity in Heart Muscle. PLoS One 2015; 10:e0124462. [PMID: 25894229 PMCID: PMC4404138 DOI: 10.1371/journal.pone.0124462] [Citation(s) in RCA: 3] [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: 10/16/2014] [Accepted: 03/03/2015] [Indexed: 01/05/2023] Open
Abstract
CUG-BP, Elav-like family (CELF) proteins regulate cell type- and developmental stage-specific alternative splicing in the heart. Repression of CELF-mediated splicing activity via expression of a nuclear dominant negative CELF protein in heart muscle was previously shown to induce dysregulation of alternative splicing, cardiac dysfunction, cardiac hypertrophy, and dilated cardiomyopathy in MHC-CELFΔ transgenic mice. A “mild” line of MHC-CELFΔ mice that expresses a lower level of the dominant negative protein exhibits cardiac dysfunction and myopathy at a young age, but spontaneously recovers normal cardiac function and heart size with age despite the persistence of splicing defects. To the best of our knowledge, this was the first example of a genetically induced cardiomyopathy that spontaneously recovers without intervention. In this study, we explored the basis for this recovery. We examined whether a transcriptional program regulated by serum response factor (SRF) that is dysregulated in juvenile MHC-CELFΔ mice is restored in the mild line with age, and evaluated global changes in gene expression by microarray analyses. We found that differences in gene expression between the mild line and wild type hearts are greatly reduced in older animals, including a partial recovery of SRF target gene expression. We did not find evidence of a new compensatory pathway being activated in the mild line with age, and propose that recovery may occur due to developmental stage-specific compatibility of CELF-dependent splice variants with the cellular environment of the cardiomyocyte.
Collapse
Affiliation(s)
- Twishasri Dasgupta
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Ryan J. Coram
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Samantha J. Stillwagon
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Andrea N. Ladd
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
- * E-mail:
| |
Collapse
|
30
|
Disease-targeted sequencing of ion channel genes identifies de novo mutations in patients with non-familial Brugada syndrome. Sci Rep 2014; 4:6733. [PMID: 25339316 PMCID: PMC4206841 DOI: 10.1038/srep06733] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 10/02/2014] [Indexed: 01/30/2023] Open
Abstract
Brugada syndrome (BrS) is one of the ion channelopathies associated with sudden cardiac death (SCD). The most common BrS-associated gene (SCN5A) only accounts for approximately 20–25% of BrS patients. This study aims to identify novel mutations across human ion channels in non-familial BrS patients without SCN5A variants through disease-targeted sequencing. We performed disease-targeted multi-gene sequencing across 133 human ion channel genes and 12 reported BrS-associated genes in 15 unrelated, non-familial BrS patients without SCN5A variants. Candidate variants were validated by mass spectrometry and Sanger sequencing. Five de novo mutations were identified in four genes (SCNN1A, KCNJ16, KCNB2, and KCNT1) in three BrS patients (20%). Two of the three patients presented SCD and one had syncope. Interestingly, the two patients presented with SCD had compound mutations (SCNN1A:Arg350Gln and KCNB2:Glu522Lys; SCNN1A:Arg597* and KCNJ16:Ser261Gly). Importantly, two SCNN1A mutations were identified from different families. The KCNT1:Arg1106Gln mutation was identified in a patient with syncope. Bioinformatics algorithms predicted severe functional interruptions in these four mutation loci, suggesting their pivotal roles in BrS. This study identified four novel BrS-associated genes and indicated the effectiveness of this disease-targeted sequencing across ion channel genes for non-familial BrS patients without SCN5A variants.
Collapse
|
31
|
Genomic biomarkers of SUDEP in brain and heart. Epilepsy Behav 2014; 38:172-9. [PMID: 24139807 PMCID: PMC3989471 DOI: 10.1016/j.yebeh.2013.09.019] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 09/12/2013] [Accepted: 09/15/2013] [Indexed: 01/22/2023]
Abstract
Sudden unexpected death in epilepsy (SUDEP) is the leading cause of epilepsy-related mortality, but how to predict which patients are at risk and how to prevent it remain uncertain. The underlying pathomechanisms of SUDEP are still largely unknown, but the general consensus is that seizures somehow disrupt normal cardiac or respiratory physiology leading to death. However, the proportion of SUDEP cases exhibiting cardiac or respiratory dysfunction as a critical factor in the terminal cascade of events remains unresolved. Although many general risk factors for SUDEP have been identified, the development of reliable patient-specific biomarkers for SUDEP is needed to provide more accurate risk prediction and personalized patient management strategies. Studies in animal models and patient groups have revealed at least nine different brain-heart genes that may contribute to a genetic susceptibility for SUDEP, making them potentially useful as genomic biomarkers. This review summarizes data on the relationship between these neurocardiac genes and SUDEP, discussing their brain-heart expression patterns and genotype-phenotype correlations in mouse models and people with epilepsy. These neurocardiac genes represent good first candidates for evaluation as genomic biomarkers of SUDEP in future studies. The development of validated reliable genomic biomarkers for SUDEP has the potential to transform the clinical treatment of epilepsy by pinpointing patients at risk of SUDEP and allowing optimized, genotype-guided therapeutic and prevention strategies.
Collapse
|
32
|
Lai MH, Wu Y, Gao Z, Anderson ME, Dalziel JE, Meredith AL. BK channels regulate sinoatrial node firing rate and cardiac pacing in vivo. Am J Physiol Heart Circ Physiol 2014; 307:H1327-38. [PMID: 25172903 DOI: 10.1152/ajpheart.00354.2014] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Large-conductance Ca(2+)- and voltage-activated K(+) (BK) channels play prominent roles in shaping muscle and neuronal excitability. In the cardiovascular system, BK channels promote vascular relaxation and protect against ischemic injury. Recently, inhibition of BK channels has been shown to lower heart rate in intact rodents and isolated hearts, suggesting a novel role in heart function. However, the underlying mechanism is unclear. In the present study, we recorded ECGs from mice injected with paxilline (PAX), a membrane-permeable BK channel antagonist, and examined changes in cardiac conduction. ECGs revealed a 19 ± 4% PAX-induced reduction in heart rate in wild-type but not BK channel knockout (Kcnma1(-/-)) mice. The heart rate decrease was associated with slowed cardiac pacing due to elongation of the sinus interval. Action potential firing recorded from isolated sinoatrial node cells (SANCs) was reduced by 55 ± 15% and 28 ± 9% by application of PAX (3 μM) and iberiotoxin (230 nM), respectively. Furthermore, baseline firing rates from Kcnma1(-/-) SANCs were 33% lower than wild-type SANCs. The slowed firing upon BK current inhibition or genetic deletion was due to lengthening of the diastolic depolarization phase of the SANC action potential. Finally, BK channel immunoreactivity and PAX-sensitive currents were identified in SANCs with HCN4 expression and pacemaker current, respectively, and BK channels cloned from SANCs recapitulated similar activation as the PAX-sensitive current. Together, these data localize BK channels to SANCs and demonstrate that loss of BK current decreases SANC automaticity, consistent with slowed sinus pacing after PAX injection in vivo. Furthermore, these findings suggest BK channels are potential therapeutic targets for disorders of heart rate.
Collapse
Affiliation(s)
- Michael H Lai
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland; Fischell Department of Bioengineering, University of Maryland, College Park, Maryland
| | - Yuejin Wu
- Department of Internal Medicine and the François M. Abboud Cardiovascular Research Center, University of Iowa, Iowa City, Iowa
| | - Zhan Gao
- Department of Internal Medicine and the François M. Abboud Cardiovascular Research Center, University of Iowa, Iowa City, Iowa
| | - Mark E Anderson
- Department of Internal Medicine and the François M. Abboud Cardiovascular Research Center, University of Iowa, Iowa City, Iowa; Department of Physiology and Molecular Biophysics, University of Iowa, Iowa City, Iowa; and
| | - Julie E Dalziel
- AgResearch, Grasslands Research Centre, Palmerston North, New Zealand
| | - Andrea L Meredith
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland; Fischell Department of Bioengineering, University of Maryland, College Park, Maryland;
| |
Collapse
|
33
|
Baumgartner S, Halbach M, Krausgrill B, Maass M, Srinivasan SP, Sahito RGA, Peinkofer G, Nguemo F, Müller-Ehmsen J, Hescheler J. Electrophysiological and morphological maturation of murine fetal cardiomyocytes during electrical stimulation in vitro. J Cardiovasc Pharmacol Ther 2014; 20:104-12. [PMID: 24917562 DOI: 10.1177/1074248414536273] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The aim of this study was to investigate whether continuous electrical stimulation affects electrophysiological properties and cell morphology of fetal cardiomyocytes (FCMs) in culture. Fetal cardiomyocytes at day 14.5 post coitum were harvested from murine hearts and electrically stimulated for 6 days in culture using a custom-made stimulation chamber. Subsequently, action potentials of FCM were recorded with glass microelectrodes. Immunostainings of α-Actinin, connexin 43, and vinculin were performed. Expression of ion channel subunits Kcnd2, Slc8a1, Cacna1, Kcnh2, and Kcnb1 was analyzed by quantitative reverse-transcriptase polymerase chain reaction. Action potential duration to 50% and 90% repolarization (APD50 and APD90) of electrically stimulated FCMs were significantly decreased when compared to nonstimulated control FCM. Alignment of cells was significantly higher in stimulated FCM when compared to control FCM. The expression of connexin 43 was significantly increased in stimulated FCM when compared to control FCM. The ratio between cell length and cell width of the stimulated FCM was significantly higher than in control FCM. Kcnh2 and Kcnd2 were upregulated in stimulated FCM when compared to control FCM. Expression of Slc8a1, Cacna1c, and Kcnb1 was not different in stimulated and control FCMs. The decrease in APD50 observed after electrical stimulation of FCM in vitro corresponds to the electrophysiological maturation of FCM in vivo. Expression levels of ion channels suggest that some important but not all aspects of the complex process of electrophysiological maturation are promoted by electrical stimulation. Parallel alignment, increased connexin 43 expression, and elongation of FCM are signs of a morphological maturation induced by electrical stimulation.
Collapse
Affiliation(s)
- Sven Baumgartner
- Department of Internal Medicine III-Cardiology, University of Cologne, Cologne, Germany Institute of Neurophysiology, University of Cologne, Cologne, Germany
| | - Marcel Halbach
- Department of Internal Medicine III-Cardiology, University of Cologne, Cologne, Germany Institute of Neurophysiology, University of Cologne, Cologne, Germany
| | - Benjamin Krausgrill
- Department of Internal Medicine III-Cardiology, University of Cologne, Cologne, Germany Institute of Neurophysiology, University of Cologne, Cologne, Germany
| | - Martina Maass
- Department of Internal Medicine III-Cardiology, University of Cologne, Cologne, Germany
| | | | | | - Gabriel Peinkofer
- Department of Internal Medicine III-Cardiology, University of Cologne, Cologne, Germany Institute of Neurophysiology, University of Cologne, Cologne, Germany
| | - Filomain Nguemo
- Institute of Neurophysiology, University of Cologne, Cologne, Germany
| | | | - Jürgen Hescheler
- Institute of Neurophysiology, University of Cologne, Cologne, Germany
| |
Collapse
|
34
|
Cardiac functions of voltage-gated Ca(2+) channels: role of the pharmacoresistant type (E-/R-Type) in cardiac modulation and putative implication in sudden unexpected death in epilepsy (SUDEP). Rev Physiol Biochem Pharmacol 2014; 167:115-39. [PMID: 25280639 DOI: 10.1007/112_2014_21] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Voltage-gated Ca(2+) channels (VGCCs) are ubiquitous in excitable cells. These channels play key roles in many physiological events like cardiac regulation/pacemaker activity due to intracellular Ca(2+) transients. In the myocardium, the Cav1 subfamily (L-type: Cav1.2 and Cav1.3) is the main contributor to excitation-contraction coupling and/or pacemaking, whereas the Cav3 subfamily (T-type: Cav3.1 and Cav3.2) is important in rhythmically firing of the cardiac nodal cells. No established cardiac function has been attributed to the Cav2 family (E-/R-type: Cav2.3) despite accumulating evidence of cardiac dysregulation observed upon deletion of the Cav2.3 gene, the only member of this family so far detected in cardiomyocytes. In this review, we summarize the pathophysiological changes observed after ablation of the E-/R-type VGCC and propose a cardiac mechanism of action for this channel. Also, considering the role played by this channel in epilepsy and its reported sensitivity to antiepileptic drugs, a putative involvement of this channel in the cardiac mechanism of sudden unexpected death in epilepsy is also discussed.
Collapse
|
35
|
Lessons from the heart: mirroring electrophysiological characteristics during cardiac development to in vitro differentiation of stem cell derived cardiomyocytes. J Mol Cell Cardiol 2013; 67:12-25. [PMID: 24370890 DOI: 10.1016/j.yjmcc.2013.12.011] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 11/14/2013] [Accepted: 12/13/2013] [Indexed: 01/12/2023]
Abstract
The ability of human pluripotent stem cells (hPSCs) to differentiate into any cell type of the three germ layers makes them a very promising cell source for multiple purposes, including regenerative medicine, drug discovery, and as a model to study disease mechanisms and progression. One of the first specialized cell types to be generated from hPSC was cardiomyocytes (CM), and differentiation protocols have evolved over the years and now allow for robust and large-scale production of hPSC-CM. Still, scientists are struggling to achieve the same, mainly ventricular, phenotype of the hPSC-CM in vitro as their adult counterpart in vivo. In vitro generated cardiomyocytes are generally described as fetal-like rather than adult. In this review, we compare the in vivo development of cardiomyocytes to the in vitro differentiation of hPSC into CM with focus on electrophysiology, structure and contractility. Furthermore, known epigenetic changes underlying the differences between adult human CM and CM differentiated from pluripotent stem cells are described. This should provide the reader with an extensive overview of the current status of human stem cell-derived cardiomyocyte phenotype and function. Additionally, the reader will gain insight into the underlying signaling pathways and mechanisms responsible for cardiomyocyte development.
Collapse
|
36
|
Takahashi K, Naruse K. Stretch-activated BK channel and heart function. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2013; 110:239-44. [PMID: 23281538 DOI: 10.1016/j.pbiomolbio.2012.08.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The heart is an organ that is exposed to extreme dynamic mechanical stimuli. From birth till death, the heart indefinitely repeats periodic contraction and dilation, i.e., shortening and elongation of cardiomyocytes. Mechanical stretch elicits a change in heart rate and may cause arrhythmia if it is excessive. Thus, mechanosensitivity is crucial to heart function. The molecule that is substantially involved in mechanosensitivity is a stretch-activated ion channel. Among several ion channels believed to be activated by stretch in the heart, the stretch-activated KCa (SAKCA) channel, a member of the group of large conductance (Big Potassium, BK) channels, shows a mechanosensitive (MS) response to membrane stretch. As BK channels respond to voltage and intracellular calcium concentration with large conductance, they are considered to be involved in repolarization after depolarization. Some BK channels are known to be activated by stretch and are expressed in a number of cells, including human osteoblasts and guinea pig intestinal neurons. The SAKCA channel was found to be sensitive to stretch in the chick heart. Given that the cardiomyocyte is unremittingly exposed to contraction and dilation and that it generates action potential and its contractility is modulated by intracellular calcium concentration, the SAKCA channel, which is dependent voltage and calcium, may be involved in action potential generation. It was recently reported that a BK channel is involved in the modulation of heart rate in the mouse. Further studies regarding the role of MS BK channels, including SAKCA, in the modulation of heart rate and contractility are expected.
Collapse
Affiliation(s)
- Ken Takahashi
- Department of Cardiovascular Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
| | | |
Collapse
|
37
|
Blech-Hermoni Y, Ladd AN. RNA binding proteins in the regulation of heart development. Int J Biochem Cell Biol 2013; 45:2467-78. [PMID: 23973289 DOI: 10.1016/j.biocel.2013.08.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 08/09/2013] [Accepted: 08/13/2013] [Indexed: 11/28/2022]
Abstract
In vivo, RNA molecules are constantly accompanied by RNA binding proteins (RBPs), which are intimately involved in every step of RNA biology, including transcription, editing, splicing, transport and localization, stability, and translation. RBPs therefore have opportunities to shape gene expression at multiple levels. This capacity is particularly important during development, when dynamic chemical and physical changes give rise to complex organs and tissues. This review discusses RBPs in the context of heart development. Since the targets and functions of most RBPs--in the heart and at large--are not fully understood, this review focuses on the expression and roles of RBPs that have been implicated in specific stages of heart development or developmental pathology. RBPs are involved in nearly every stage of cardiogenesis, including the formation, morphogenesis, and maturation of the heart. A fuller understanding of the roles and substrates of these proteins could ultimately provide attractive targets for the design of therapies for congenital heart defects, cardiovascular disease, or cardiac tissue repair.
Collapse
Affiliation(s)
- Yotam Blech-Hermoni
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA; Program in Cell Biology, Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | | |
Collapse
|
38
|
Linta L, Stockmann M, Lin Q, Lechel A, Proepper C, Boeckers TM, Kleger A, Liebau S. Microarray-Based Comparisons of Ion Channel Expression Patterns: Human Keratinocytes to Reprogrammed hiPSCs to Differentiated Neuronal and Cardiac Progeny. Stem Cells Int 2013; 2013:784629. [PMID: 23690787 PMCID: PMC3649712 DOI: 10.1155/2013/784629] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 03/06/2013] [Indexed: 11/17/2022] Open
Abstract
Ion channels are involved in a large variety of cellular processes including stem cell differentiation. Numerous families of ion channels are present in the organism which can be distinguished by means of, for example, ion selectivity, gating mechanism, composition, or cell biological function. To characterize the distinct expression of this group of ion channels we have compared the mRNA expression levels of ion channel genes between human keratinocyte-derived induced pluripotent stem cells (hiPSCs) and their somatic cell source, keratinocytes from plucked human hair. This comparison revealed that 26% of the analyzed probes showed an upregulation of ion channels in hiPSCs while just 6% were downregulated. Additionally, iPSCs express a much higher number of ion channels compared to keratinocytes. Further, to narrow down specificity of ion channel expression in iPS cells we compared their expression patterns with differentiated progeny, namely, neurons and cardiomyocytes derived from iPS cells. To conclude, hiPSCs exhibit a very considerable and diverse ion channel expression pattern. Their detailed analysis could give an insight into their contribution to many cellular processes and even disease mechanisms.
Collapse
Affiliation(s)
- Leonhard Linta
- Institute for Anatomy Cell Biology, Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Marianne Stockmann
- Institute for Anatomy Cell Biology, Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Qiong Lin
- Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen, Pauwelstrasse 30, 52074 Aachen, Germany
| | - André Lechel
- Department of Internal Medicine I, Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Christian Proepper
- Institute for Anatomy Cell Biology, Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Tobias M. Boeckers
- Institute for Anatomy Cell Biology, Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Alexander Kleger
- Department of Internal Medicine I, Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Stefan Liebau
- Institute for Anatomy Cell Biology, Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany
| |
Collapse
|
39
|
Nenasheva TA, Neary M, Mashanov GI, Birdsall NJ, Breckenridge RA, Molloy JE. Abundance, distribution, mobility and oligomeric state of M₂ muscarinic acetylcholine receptors in live cardiac muscle. J Mol Cell Cardiol 2013; 57:129-36. [PMID: 23357106 PMCID: PMC3605596 DOI: 10.1016/j.yjmcc.2013.01.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Revised: 12/21/2012] [Accepted: 01/11/2013] [Indexed: 11/10/2022]
Abstract
M2 muscarinic acetylcholine receptors modulate cardiac rhythm via regulation of the inward potassium current. To increase our understanding of M2 receptor physiology we used Total Internal Reflection Fluorescence Microscopy to visualize individual receptors at the plasma membrane of transformed CHO(M2) cells, a cardiac cell line (HL-1), primary cardiomyocytes and tissue slices from pre- and post-natal mice. Receptor expression levels between individual cells in dissociated cardiomyocytes and heart slices were highly variable and only 10% of murine cardiomyocytes expressed muscarinic receptors. M2 receptors were evenly distributed across individual cells and their density in freshly isolated embryonic cardiomyocytes was ~1μm(-2), increasing at birth (to ~3μm(-2)) and decreasing back to ~1μm(-2) after birth. M2 receptors were primarily monomeric but formed reversible dimers. They diffused freely at the plasma membrane, moving approximately 4-times faster in heart slices than in cultured cardiomyocytes. Knowledge of receptor density and mobility has allowed receptor collision rate to be modeled by Monte Carlo simulations. Our estimated encounter rate of 5-10 collisions per second, may explain the latency between acetylcholine application and GIRK channel opening.
Collapse
Affiliation(s)
- Tatiana A. Nenasheva
- Division of Physical Biochemistry, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
| | - Marianne Neary
- Division of Developmental Biology, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
| | - Gregory I. Mashanov
- Division of Physical Biochemistry, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
| | - Nigel J.M. Birdsall
- Division of Physical Biochemistry, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
| | - Ross A. Breckenridge
- Division of Developmental Biology, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
| | - Justin E. Molloy
- Division of Physical Biochemistry, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
| |
Collapse
|
40
|
Bao L, Taskin E, Foster M, Ray B, Rosario R, Ananthakrishnan R, Howlett SE, Schmidt AM, Ramasamy R, Coetzee WA. Alterations in ventricular K(ATP) channel properties during aging. Aging Cell 2013; 12:167-76. [PMID: 23173756 DOI: 10.1111/acel.12033] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/12/2012] [Indexed: 12/27/2022] Open
Abstract
Coronary heart disease remains the principle cause of mortality in the United States. During aging, the efficiency of the cardiovascular system is decreased and the aged heart is less tolerant to ischemic injury. ATP-sensitive K(+) (K(ATP)) channels protect the myocardium against ischemic damage. We investigated how aging affects cardiac K(ATP) channels in the Fischer 344 rat model. Expression of K(ATP) channel subunit mRNA and protein levels was unchanged in hearts from 26-month-old vs. 4-month-old rats. Interestingly, the mRNA expression of several other ion channels (> 80) was also largely unchanged, suggesting that posttranscriptional regulatory mechanisms occur during aging. The whole-cell K(ATP) channel current density was strongly diminished in ventricular myocytes from aged male rat hearts (also observed in aged C57BL/6 mouse myocytes). Experiments with isolated patches (inside-out configuration) demonstrated that the K(ATP) channel unitary conductance was unchanged, but that the inhibitory effect of cytosolic ATP on channel activity was enhanced in the aged heart. The mean patch current was diminished, consistent with the whole-cell data. We incorporated these findings into an empirical model of the K(ATP) channel and numerically simulated the effects of decreased cytosolic ATP levels on the human action potential. This analysis predicts lesser activation of K(ATP) channels by metabolic impairment in the aged heart and a diminished action potential shortening. This study provides insights into the changes in K(ATP) channels during aging and suggests that the protective role of these channels during ischemia is significantly compromised in the aged individual.
Collapse
Affiliation(s)
- Li Bao
- Pediatrics; NYU School of Medicine; New York; NY; USA
| | - Eylem Taskin
- Pediatrics; NYU School of Medicine; New York; NY; USA
| | | | - Beevash Ray
- Medicine; NYU School of Medicine; New York; NY; USA
| | - Rosa Rosario
- Medicine; NYU School of Medicine; New York; NY; USA
| | | | - Susan E. Howlett
- Department of Pharmacology; Dalhousie University; 5850 College Street; PO Box 15000; Sir Charles Tupper Medical Building; Halifax; Nova Scotia; Canada; B3H 4R2
| | | | | | | |
Collapse
|
41
|
Truncation of murine CaV1.2 at Asp 1904 increases CaV1.3 expression in embryonic atrial cardiomyocytes. Pflugers Arch 2013; 465:955-64. [PMID: 23338940 DOI: 10.1007/s00424-012-1212-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Revised: 12/18/2012] [Accepted: 12/19/2012] [Indexed: 12/25/2022]
Abstract
Cardiac CaV1.2 channels play a critical role in cardiac function. It has been proposed that the carboxyl-terminal intracellular tail of the CaV1.2 channel is the target of Ca(2+)-dependent and Ca(2+)-independent regulation of the channel. Recent studies on C-terminal truncated forms of the CaV1.2 channel reported neonatal death, reduced CaV1.2 current, and failure of β-adrenergic stimulation of these channels in ventricular cardiomyocytes (CMs). Here, we used atrial CMs at embryonic day 18.5 that expressed a C-terminal truncated form of the CaV1.2 channel (Stop/Stop). Surprisingly, the atrial CMs showed robust L-type Ca(2+) currents which could be stimulated by forskolin, an activator of adenylyl cyclase. These currents exhibited a left-ward shift in the voltage-dependent activation curve and a reduced sensitivity to the Ca(2+) channel blocker isradipine as compared to currents in wild-type atrial CMs. RT-PCR analysis revealed normal levels of mRNA for the CaV1.2 channel but a twofold increase in the level of mRNA for the CaV1.3 channel in the Stop/Stop atrium as compared to wild-type atrium. A Western blot analysis indicated an increase of CaV1.3 protein in the Stop/Stop atrium. We suggest that, in contrast to Stop/Stop ventricular CMs, Stop/Stop atrial CMs can compensate the functional loss of the truncated CaV1.2 channel with an upregulation of the CaV1.3 channel.
Collapse
|
42
|
Hamaguchi S, Kawakami Y, Honda Y, Nemoto K, Sano A, Namekata I, Tanaka H. Developmental Changes in Excitation–Contraction Mechanisms of the Mouse Ventricular Myocardium as Revealed by Functional and Confocal Imaging Analyses. J Pharmacol Sci 2013; 123:167-75. [DOI: 10.1254/jphs.13099fp] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
|
43
|
Ruhle B, Trebak M. Emerging roles for native Orai Ca2+ channels in cardiovascular disease. CURRENT TOPICS IN MEMBRANES 2013; 71:209-35. [PMID: 23890117 DOI: 10.1016/b978-0-12-407870-3.00009-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Orai proteins form highly calcium (Ca(2+))-selective channels located in the plasma membrane of both nonexcitable and excitable cells, where they make important contributions to many cellular processes. The well-characterized Ca(2+) release-activated Ca(2+) current is mediated by Orai1 multimers and is activated, upon depletion of inositol 1,4,5-trisphosphate-sensitive stores, by direct interaction of Orai1 with the endoplasmic reticulum Ca(2+) sensor, stromal interaction molecule 1 (STIM1). This pathway is known as capacitative Ca(2+) entry or store-operated Ca(2+) entry. While most investigations have focused on STIM1 and Orai1 in their store-dependent mode, emerging evidence suggests that Orai1 and Orai3 heteromultimeric channels can form store-independent Ca(2+)-selective channels. The role of store-dependent and store-independent channels in excitation-transcription coupling and the pathological remodeling of the cardiovascular system are beginning to come forth. Recent evidence suggests that STIM/Orai-generated Ca(2+) signaling couples to gene transcription and subsequent phenotypic changes associated with the processes of cardiac and vascular remodeling. This short review will explore the contributions of native Orai channels to heart and vessel physiology and their role in cardiovascular diseases.
Collapse
Affiliation(s)
- Brian Ruhle
- Nanobioscience Constellation, The College of Nanoscale Science and Engineering, University at Albany-State University of New York, Albany, NY, USA
| | | |
Collapse
|
44
|
Histological and ultrastructural abnormalities in murine desmoglein 2-mutant hearts. Cell Tissue Res 2012; 348:249-59. [PMID: 22293975 DOI: 10.1007/s00441-011-1322-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Accepted: 12/16/2011] [Indexed: 12/21/2022]
Abstract
Mice carrying a deletion of the adhesive extracellular domain of the desmosomal cadherin desmoglein 2 develop an arrhythmogenic right ventricular cardiomyopathylike phenotype with ventricular dilation, fibrosis and arrhythmia. To unravel the sequence of myocardial alterations and to identify potential pathomechanisms, histological analyses were performed on mutant hearts from the juvenile to the adult state, i.e., between 2 and 13 weeks. At an age of 2 weeks 30% of mutants presented lesions,which were visible as white plaques on the heart surface or in the septum. From 4 weeks onwards, all mutants displayed a cardiac phenotype. Dying cardiomyocytes with calcification were found in lesions of all ages. But lesions of young mutant animals contained high amounts of CD45+ immune cells and little collagen fibers, whereas lesions of the older animals were collagen-rich and harbored only a small but still significantly increased number of CD45+ cells. Electron microscopy further showed that distinct desmosomes cannot be distinguished in intercalated discs of mutant hearts. Widening of the intercellular cleft and even complete dissociation of intercalated discs were often observed close to lesions. Disturbed sarcomer structure, altered Z-discs, multiple autophagic vacuoles and swollen mitochondria were other prominent pathological features. Taken together, the following scenario is suggested: mutant desmoglein 2 cannot fully support the increased mechanical requirements placed on intercalated disc adhesion during postnatal heart development, resulting in compromised adhesion and cell stress. This induces cardiomyocyte death, aseptic inflammation and fibrotic replacement. The acute stage of scar formation is followed by permanent impairment of the cardiac function.
Collapse
|
45
|
Danielsson C, Brask J, Sköld AC, Genead R, Andersson A, Andersson U, Stockling K, Pehrson R, Grinnemo KH, Salari S, Hellmold H, Danielsson B, Sylvén C, Elinder F. Exploration of human, rat, and rabbit embryonic cardiomyocytes suggests K-channel block as a common teratogenic mechanism. Cardiovasc Res 2012; 97:23-32. [DOI: 10.1093/cvr/cvs296] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
46
|
Otsuji TG, Kurose Y, Suemori H, Tada M, Nakatsuji N. Dynamic link between histone H3 acetylation and an increase in the functional characteristics of human ESC/iPSC-derived cardiomyocytes. PLoS One 2012; 7:e45010. [PMID: 22984602 PMCID: PMC3440326 DOI: 10.1371/journal.pone.0045010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 08/15/2012] [Indexed: 01/09/2023] Open
Abstract
Cardiomyocytes (CMs) derived from human embryonic stem cells (hESCs) or human induced pluripotent stem cells (hiPSCs) are functionally heterogeneous, display insufficient biological efficacy and generally possess the electrophysiological properties seen in fetal CMs. However, a homogenous population of hESC/hiPSC-CMs, with properties similar to those of adult human ventricular cells, is required for use in drug cardiotoxicity screening. Unfortunately, despite the requirement for the functional characteristics of post-mitotic beating cell aggregates to mimic the behavior of mature cardiomyocytes in vitro, few technological improvements have been made in this field to date. Previously, we showed that culturing hESC-CMs under low-adhesion conditions with cyclic replating confers continuous contractility on the cells, leading to a functional increase in cardiac gene expression and electrophysiological properties over time. The current study reveals that culturing hESC/hiPSC-CMs under non-adhesive culture conditions enhances the electrophysiological properties of the CMs through an increase in the acetylation of histone H3 lysine residues, as confirmed by western blot analyses. Histone H3 acetylation was induced chemically by treating primitive hESC/hiPSC-CMs with Trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, resulting in an immediate increase in global cardiac gene expression. In functional analyses using multi-electrode array (MEA) recordings, TSA-treated hESC/hiPSC-CM colonies showed appropriate responses to particular concentrations of known potassium ion channel inhibitors. Thus, the combination of a cell-autonomous functional increase in response to non-adhesive culture and short-term TSA treatment of hESC/hiPSC-CM colonies cultured on MEA electrodes will help to make cardiac toxicity tests more accurate and reproducible via genome-wide chromatin activation.
Collapse
Affiliation(s)
- Tomomi G. Otsuji
- Stem Cell and Drug Discovery Institute, Kyoto, Japan
- Institute for Frontier Medical Sciences, Kyoto University, Kawahara-cho, Sakyo-ku, Kyoto, Japan
- Institute for Integrated Cell-Material Sciences, Kyoto University, Ushinomiya-cho, Yoshida, Sakyo-ku, Kyoto, Japan
| | - Yuko Kurose
- Stem Cell and Drug Discovery Institute, Kyoto, Japan
| | - Hirofumi Suemori
- Institute for Frontier Medical Sciences, Kyoto University, Kawahara-cho, Sakyo-ku, Kyoto, Japan
| | - Masako Tada
- Stem Cell and Drug Discovery Institute, Kyoto, Japan
- Chromosome Engineering Research Center, Tottori University, Yonago, Tottori, Japan
- * E-mail:
| | - Norio Nakatsuji
- Institute for Frontier Medical Sciences, Kyoto University, Kawahara-cho, Sakyo-ku, Kyoto, Japan
- Institute for Integrated Cell-Material Sciences, Kyoto University, Ushinomiya-cho, Yoshida, Sakyo-ku, Kyoto, Japan
| |
Collapse
|
47
|
Toib A, Zhang HX, Broekelmann TJ, Hyrc KL, Guo Q, Chen F, Remedi MS, Nichols CG. Cardiac specific ATP-sensitive K+ channel (KATP) overexpression results in embryonic lethality. J Mol Cell Cardiol 2012; 53:437-45. [PMID: 22796573 PMCID: PMC3423334 DOI: 10.1016/j.yjmcc.2012.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2012] [Revised: 06/23/2012] [Accepted: 07/02/2012] [Indexed: 11/26/2022]
Abstract
Transgenic mice overexpressing SUR1 and gain of function Kir6.2[∆N30, K185Q] K(ATP) channel subunits, under cardiac α-myosin heavy chain (αMHC) promoter control, demonstrate arrhythmia susceptibility and premature death. Pregnant mice, crossed to carry double transgenic progeny, which harbor high levels of both overexpressed subunits, exhibit the most extreme phenotype and do not deliver any double transgenic pups. To explore the fetal lethality and embryonic phenotype that result from K(ATP) overexpression, wild type (WT) and K(ATP) overexpressing embryonic cardiomyocytes were isolated, cultured and voltage-clamped using whole cell and excised patch clamp techniques. Whole mount embryonic imaging, Hematoxylin and Eosin (H&E) and α smooth muscle actin (αSMA) immunostaining were used to assess anatomy, histology and cardiac development in K(ATP) overexpressing and WT embryos. Double transgenic embryos developed in utero heart failure and 100% embryonic lethality by 11.5 days post conception (dpc). K(ATP) currents were detectable in both WT and K(ATP)-overexpressing embryonic cardiomyocytes, starting at early stages of cardiac development (9.5 dpc). In contrast to adult cardiomyocytes, WT and K(ATP)-overexpressing embryonic cardiomyocytes exhibit basal and spontaneous K(ATP) current, implying that these channels may be open and active under physiological conditions. At 9.5 dpc, live double transgenic embryos demonstrated normal looping pattern, although all cardiac structures were collapsed, probably representing failed, non-contractile chambers. In conclusion, K(ATP) channels are present and active in embryonic myocytes, and overexpression causes in utero heart failure and results in embryonic lethality. These results suggest that the K(ATP) channel may have an important physiological role during early cardiac development.
Collapse
Affiliation(s)
- Amir Toib
- Department of Pediatrics, St. Louis, MO, 63110, USA.
| | | | | | | | | | | | | | | |
Collapse
|
48
|
Abd Allah ES, Aslanidi OV, Tellez JO, Yanni J, Billeter R, Zhang H, Dobrzynski H, Boyett MR. Postnatal development of transmural gradients in expression of ion channels and Ca2+-handling proteins in the ventricle. J Mol Cell Cardiol 2012; 53:145-55. [DOI: 10.1016/j.yjmcc.2012.04.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 03/06/2012] [Accepted: 04/06/2012] [Indexed: 01/30/2023]
|
49
|
Phoon CKL, Acehan D, Schlame M, Stokes DL, Edelman-Novemsky I, Yu D, Xu Y, Viswanathan N, Ren M. Tafazzin knockdown in mice leads to a developmental cardiomyopathy with early diastolic dysfunction preceding myocardial noncompaction. J Am Heart Assoc 2012; 1:jah313. [PMID: 23130124 PMCID: PMC3487377 DOI: 10.1161/jaha.111.000455] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 02/21/2012] [Indexed: 11/16/2022]
Abstract
BACKGROUND Barth syndrome is a rare, multisystem disorder caused by mutations in tafazzin that lead to cardiolipin deficiency and mitochondrial abnormalities. Patients most commonly develop an early-onset cardiomyopathy in infancy or fetal life. METHODS AND RESULTS Knockdown of tafazzin (TAZKD) in a mouse model was induced from the start of gestation via a doxycycline-inducible shRNA transgenic approach. All liveborn TAZKD mice died within the neonatal period, and in vivo echocardiography revealed prenatal loss of TAZKD embryos at E12.5-14.5. TAZKD E13.5 embryos and newborn mice demonstrated significant tafazzin knockdown, and mass spectrometry analysis of hearts revealed abnormal cardiolipin profiles typical of Barth syndrome. Electron microscopy of TAZKD hearts demonstrated ultrastructural abnormalities in mitochondria at both E13.5 and newborn stages. Newborn TAZKD mice exhibited a significant reduction in total mitochondrial area, smaller size of individual mitochondria, reduced cristae density, and disruption of the normal parallel orientation between mitochondria and sarcomeres. Echocardiography of E13.5 and newborn TAZKD mice showed good systolic function, but early diastolic dysfunction was evident from an abnormal flow pattern in the dorsal aorta. Strikingly, histology of E13.5 and newborn TAZKD hearts showed myocardial thinning, hypertrabeculation and noncompaction, and defective ventricular septation. Altered cellular proliferation occurring within a narrow developmental window accompanied the myocardial hypertrabeculation-noncompaction. CONCLUSIONS In this murine model, tafazzin deficiency leads to a unique developmental cardiomyopathy characterized by ventricular myocardial hypertrabeculation-noncompaction and early lethality. A central role of cardiolipin and mitochondrial functioning is strongly implicated in cardiomyocyte differentiation and myocardial patterning required for heart development. (J Am Heart Assoc. 2012;1:jah3-e000455 doi: 10.1161/JAHA.111.000455.).
Collapse
Affiliation(s)
- Colin K L Phoon
- Department of Pediatrics (Pediatric Cardiology), New York University School of Medicine, New York (C.K.L.P., N.V.)
| | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Suzuki T, Shioya T, Murayama T, Sugihara M, Odagiri F, Nakazato Y, Nishizawa H, Chugun A, Sakurai T, Daida H, Morimoto S, Kurebayashi N. Multistep ion channel remodeling and lethal arrhythmia precede heart failure in a mouse model of inherited dilated cardiomyopathy. PLoS One 2012; 7:e35353. [PMID: 22514734 PMCID: PMC3325934 DOI: 10.1371/journal.pone.0035353] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Accepted: 03/14/2012] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Patients with inherited dilated cardiomyopathy (DCM) frequently die with severe heart failure (HF) or die suddenly with arrhythmias, although these symptoms are not always observed at birth. It remains unclear how and when HF and arrhythmogenic changes develop in these DCM mutation carriers. In order to address this issue, properties of the myocardium and underlying gene expressions were studied using a knock-in mouse model of human inherited DCM caused by a deletion mutation ΔK210 in cardiac troponinT. METHODOLOGY/PRINCIPAL FINDINGS By 1 month, DCM mice had already enlarged hearts, but showed no symptoms of HF and a much lower mortality than at 2 months or later. At around 2 months, some would die suddenly with no clear symptoms of HF, whereas at 3 months, many of the survivors showed evident symptoms of HF. In isolated left ventricular myocardium (LV) from 2 month-mice, spontaneous activity frequently occurred and action potential duration (APD) was prolonged. Transient outward (I(to)) and ultrarapid delayed rectifier K(+) (I(Kur)) currents were significantly reduced in DCM myocytes. Correspondingly, down-regulation of Kv4.2, Kv1.5 and KChIP2 was evident in mRNA and protein levels. In LVs at 3-months, more frequent spontaneous activity, greater prolongation of APD and further down-regulation in above K(+) channels were observed. At 1 month, in contrast, infrequent spontaneous activity and down-regulation of Kv4.2, but not Kv1.5 or KChIP2, were observed. CONCLUSIONS/SIGNIFICANCE Our results suggest that at least three steps of electrical remodeling occur in the hearts of DCM model mice, and that the combined down-regulation of Kv4.2, Kv1.5 and KChIP2 prior to the onset of HF may play an important role in the premature sudden death in this DCM model. DCM mice at 1 month or before, on the contrary, are associated with low risk of death in spite of inborn disorder and enlarged heart.
Collapse
Affiliation(s)
- Takeshi Suzuki
- Department of Cellular and Molecular Pharmacology, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
- Department of Cardiovascular Medicine, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
| | - Takao Shioya
- Department of Physiology, Faculty of Medicine, Saga University, Saga, Japan
| | - Takashi Murayama
- Department of Cellular and Molecular Pharmacology, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
| | - Masami Sugihara
- Department of Cellular and Molecular Pharmacology, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
- Department of Cardiovascular Medicine, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
| | - Fuminori Odagiri
- Department of Cellular and Molecular Pharmacology, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
- Department of Cardiovascular Medicine, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
| | - Yuji Nakazato
- Department of Cardiovascular Medicine, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
| | - Hiroto Nishizawa
- Department of Cellular and Molecular Pharmacology, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
- Department of Cardiovascular Medicine, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
| | - Akihito Chugun
- Department of Cellular and Molecular Pharmacology, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
| | - Takashi Sakurai
- Department of Cellular and Molecular Pharmacology, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
| | - Hiroyuki Daida
- Department of Cardiovascular Medicine, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
| | - Sachio Morimoto
- Department of Clinical Pharmacology, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Nagomi Kurebayashi
- Department of Cellular and Molecular Pharmacology, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan
- * E-mail:
| |
Collapse
|