1
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Lakin R, Polidovitch N, Yang S, Parikh M, Liu X, Debi R, Gao X, Chen W, Guzman C, Yakobov S, Izaddoustdar F, Wauchop M, Lei Q, Xu W, Nedospasov SA, Christoffels VM, Backx PH. Cardiomyocyte and endothelial cells play distinct roles in the tumour necrosis factor (TNF)-dependent atrial responses and increased atrial fibrillation vulnerability induced by endurance exercise training in mice. Cardiovasc Res 2023; 119:2607-2622. [PMID: 37713664 PMCID: PMC10730243 DOI: 10.1093/cvr/cvad144] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 06/22/2023] [Accepted: 07/18/2023] [Indexed: 09/17/2023] Open
Abstract
AIMS Endurance exercise is associated with an increased risk of atrial fibrillation (AF). We previously established that adverse atrial remodelling and AF susceptibility induced by intense exercise in mice require the mechanosensitive and pro-inflammatory cytokine tumour necrosis factor (TNF). The cellular and mechanistic basis for these TNF-mediated effects is unknown. METHODS AND RESULTS We studied the impact of Tnf excision, in either atrial cardiomyocytes or endothelial cells (using Cre-recombinase expression controlled by Nppa or Tie2 promoters, respectively), on the cardiac responses to six weeks of intense swim exercise training. TNF ablation, in either cell type, had no impact on the changes in heart rate, autonomic tone, or left ventricular structure and function induced by exercise training. Tnf excision in atrial cardiomyocytes did, however, prevent atrial hypertrophy, fibrosis, and macrophage infiltration as well as conduction slowing and increased AF susceptibility arising from exercise training. In contrast, endothelial-specific excision only reduced the training-induced atrial hypertrophy. Consistent with these cell-specific effects of Tnf excision, inducing TNF loss from atrial cardiomyocytes prevented activation of p38MAPKinase, a strain-dependent downstream mediator of TNF signalling, without affecting the atrial stretch as assessed by atrial pressures induced by exercise. Despite TNF's established role in innate immune responses and inflammation, neither acute nor chronic exercise training caused measurable NLRP3 inflammasome activation. CONCLUSIONS Our findings demonstrate that adverse atrial remodelling and AF vulnerability induced by intense exercise require TNF in atrial cardiomyocytes whereas the impact of endothelial-derived TNF is limited to hypertrophy modulation. The implications of the cell autonomous effects of TNF and crosstalk between cells in the atria are discussed.
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Affiliation(s)
- Robert Lakin
- Department of Biology, York University, 354 & 357 Farquharson Building, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
| | - Nazari Polidovitch
- Department of Biology, York University, 354 & 357 Farquharson Building, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
| | - Sibao Yang
- Department of Biology, York University, 354 & 357 Farquharson Building, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
- Department of Cardiology, China-Japan Union Hospital of Jilin University, Changchun, Jilin 130022, China
| | - Mihir Parikh
- Department of Biology, York University, 354 & 357 Farquharson Building, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
| | - Xueyan Liu
- Department of Biology, York University, 354 & 357 Farquharson Building, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
- Department of Cardiology, China-Japan Union Hospital of Jilin University, Changchun, Jilin 130022, China
| | - Ryan Debi
- Department of Biology, York University, 354 & 357 Farquharson Building, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
| | - Xiaodong Gao
- Department of Biology, York University, 354 & 357 Farquharson Building, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
| | - Wenliang Chen
- Department of Biology, York University, 354 & 357 Farquharson Building, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
| | - Camilo Guzman
- Department of Biology, York University, 354 & 357 Farquharson Building, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
| | - Simona Yakobov
- Department of Biology, York University, 354 & 357 Farquharson Building, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
| | - Farzad Izaddoustdar
- Department of Physiology, University of Toronto, Toronto, ON M5S 3E2, Canada
| | - Marianne Wauchop
- Department of Physiology, University of Toronto, Toronto, ON M5S 3E2, Canada
| | - Qian Lei
- Department of Anesthesiology, Sichuan Academy of Medical Sciences and Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu 610072, China
| | - Weimin Xu
- Department of Cardiology, China-Japan Union Hospital of Jilin University, Changchun, Jilin 130022, China
| | - Sergei A Nedospasov
- Laboratory of Molecular Mechanisms of Immunity, Engelhardt Institute of Molecular Biology, Moscow 119991, Russia
- Division of Immunobiology and Biomedicine, Sirius University of Science and Technology, Sirius 354349, Russia
| | - Vincent M Christoffels
- Department of Medical Biology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, Amsterdam, The Netherlands
| | - Peter H Backx
- Department of Biology, York University, 354 & 357 Farquharson Building, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
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2
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García-Padilla C, Domínguez JN, Lodde V, Munk R, Abdelmohsen K, Gorospe M, Jiménez-Sábado V, Ginel A, Hove-Madsen L, Aránega AE, Franco D. Identification of atrial-enriched lncRNA Walras linked to cardiomyocyte cytoarchitecture and atrial fibrillation. FASEB J 2022; 36:e22051. [PMID: 34861058 PMCID: PMC8684585 DOI: 10.1096/fj.202100844rr] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 11/04/2021] [Accepted: 11/05/2021] [Indexed: 01/03/2023]
Abstract
Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia in humans. Genetic and genomic analyses have recently demonstrated that the homeobox transcription factor Pitx2 plays a fundamental role regulating expression of distinct growth factors, microRNAs and ion channels leading to morphological and molecular alterations that promote the onset of AF. Here we address the plausible contribution of long non-coding (lnc)RNAs within the Pitx2>Wnt>miRNA signaling pathway. In silico analyses of annotated lncRNAs in the vicinity of the Pitx2, Wnt8 and Wnt11 chromosomal loci identified five novel lncRNAs with differential expression during cardiac development. Importantly, three of them, Walaa, Walras, and Wallrd, are evolutionarily conserved in humans and displayed preferential atrial expression during embryogenesis. In addition, Walrad displayed moderate expression during embryogenesis but was more abundant in the right atrium. Walaa, Walras and Wallrd were distinctly regulated by Pitx2, Wnt8, and Wnt11, and Wallrd was severely elevated in conditional atrium-specific Pitx2-deficient mice. Furthermore, pro-arrhythmogenic and pro-hypertrophic substrate administration to primary cardiomyocyte cell cultures consistently modulate expression of these lncRNAs, supporting distinct modulatory roles of the AF cardiovascular risk factors in the regulation of these lncRNAs. Walras affinity pulldown assays revealed its association with distinct cytoplasmic and nuclear proteins previously involved in cardiac pathophysiology, while loss-of-function assays further support a pivotal role of this lncRNA in cytoskeletal organization. We propose that lncRNAs Walaa, Walras and Wallrd, distinctly regulated by Pitx2>Wnt>miRNA signaling and pro-arrhythmogenic and pro-hypertrophic factors, are implicated in atrial arrhythmogenesis, and Walras additionally in cardiomyocyte cytoarchitecture.
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Affiliation(s)
- Carlos García-Padilla
- Cardiovascular Development Group, Department of Experimental Biology, University of Jaen, Jaen, Spain
| | - Jorge N. Domínguez
- Cardiovascular Development Group, Department of Experimental Biology, University of Jaen, Jaen, Spain
| | - Valeria Lodde
- Laboratory of Genetics and Genomics, National Institute on Aging IRP, National Institutes of Health, Baltimore, Maryland, USA,Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - Rachel Munk
- Laboratory of Genetics and Genomics, National Institute on Aging IRP, National Institutes of Health, Baltimore, Maryland, USA
| | - Kotb Abdelmohsen
- Laboratory of Genetics and Genomics, National Institute on Aging IRP, National Institutes of Health, Baltimore, Maryland, USA
| | - Myriam Gorospe
- Laboratory of Genetics and Genomics, National Institute on Aging IRP, National Institutes of Health, Baltimore, Maryland, USA
| | | | - Antonino Ginel
- Department Cardiac Surgery, Hospital de Sant Pau, Barcelona, Spain,Biomedical Research Institute IIB Sant Pau, Barcelona, Spain
| | - Leif Hove-Madsen
- CIBERCV, Barcelona, Spain,Biomedical Research Institute IIB Sant Pau, Barcelona, Spain,Biomedical Research Institute Barcelona (IIBB-CSIC), Barcelona, Spain
| | - Amelia E. Aránega
- Cardiovascular Development Group, Department of Experimental Biology, University of Jaen, Jaen, Spain
| | - Diego Franco
- Cardiovascular Development Group, Department of Experimental Biology, University of Jaen, Jaen, Spain
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3
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Wang L, Rice M, Swist S, Kubin T, Wu F, Wang S, Kraut S, Weissmann N, Böttger T, Wheeler M, Schneider A, Braun T. BMP9 and BMP10 Act Directly on Vascular Smooth Muscle Cells for Generation and Maintenance of the Contractile State. Circulation 2020; 143:1394-1410. [PMID: 33334130 DOI: 10.1161/circulationaha.120.047375] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND Vascular smooth muscle cells (VSMCs) show a remarkable phenotypic plasticity, allowing acquisition of contractile or synthetic states, but critical information is missing about the physiologic signals, promoting formation, and maintenance of contractile VSMCs in vivo. BMP9 and BMP10 (bone morphogenetic protein) are known to regulate endothelial quiescence after secretion from the liver and right atrium, whereas a direct role in the regulation of VSMCs was not investigated. We studied the role of BMP9 and BMP10 for controlling formation of contractile VSMCs. METHODS We generated several cell type-specific loss- and gain-of-function transgenic mouse models to investigate the physiologic role of BMP9, BMP10, ALK1 (activin receptor-like kinase 1), and SMAD7 in vivo. Morphometric assessments, expression analysis, blood pressure measurements, and single molecule fluorescence in situ hybridization were performed together with analysis of isolated pulmonary VSMCs to unravel phenotypic and transcriptomic changes in response to absence or presence of BMP9 and BMP10. RESULTS Concomitant genetic inactivation of Bmp9 in the germ line and Bmp10 in the right atrium led to dramatic changes in vascular tone and diminution of the VSMC layer with attenuated contractility and decreased systemic as well as right ventricular systolic pressure. On the contrary, overexpression of Bmp10 in endothelial cells of adult mice dramatically enhanced formation of contractile VSMCs and increased systemic blood pressure as well as right ventricular systolic pressure. Likewise, BMP9/10 treatment induced an ALK1-dependent phenotypic switch from synthetic to contractile in pulmonary VSMCs. Smooth muscle cell-specific overexpression of Smad7 completely suppressed differentiation and proliferation of VSMCs and reiterated defects observed in adult Bmp9/10 double mutants. Deletion of Alk1 in VSMCs recapitulated the Bmp9/10 phenotype in pulmonary but not in aortic and coronary arteries. Bulk expression analysis and single molecule RNA-fluorescence in situ hybridization uncovered vessel bed-specific, heterogeneous expression of BMP type 1 receptors, explaining phenotypic differences in different Alk1 mutant vessel beds. CONCLUSIONS Our study demonstrates that BMP9 and BMP10 act directly on VSMCs for induction and maintenance of their contractile state. The effects of BMP9/10 in VSMCs are mediated by different combinations of BMP type 1 receptors in a vessel bed-specific manner, offering new opportunities to manipulate blood pressure in the pulmonary circulation.
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Affiliation(s)
- Lei Wang
- Departments of Cardiac Development and Remodeling (L.W., M.R., S.S., F.W., T.B., M.W., A.S., T.B.)
| | - Megan Rice
- Departments of Cardiac Development and Remodeling (L.W., M.R., S.S., F.W., T.B., M.W., A.S., T.B.)
| | - Sandra Swist
- Departments of Cardiac Development and Remodeling (L.W., M.R., S.S., F.W., T.B., M.W., A.S., T.B.)
| | | | - Fan Wu
- Departments of Cardiac Development and Remodeling (L.W., M.R., S.S., F.W., T.B., M.W., A.S., T.B.)
| | - Shengpeng Wang
- Cardiac Surgery (S.W.), Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Simone Kraut
- Excellence Cluster Cardiopulmonary System, University of Giessen Lung Center, German Center for Lung Research (DZL), Justus-Liebig-University, Giessen, Germany (S.K., N.W.)
| | - Norbert Weissmann
- Excellence Cluster Cardiopulmonary System, University of Giessen Lung Center, German Center for Lung Research (DZL), Justus-Liebig-University, Giessen, Germany (S.K., N.W.).,German Centre for Lung Research (DZL), Partner site Giessen, Germany (N.W.)
| | - Thomas Böttger
- Departments of Cardiac Development and Remodeling (L.W., M.R., S.S., F.W., T.B., M.W., A.S., T.B.)
| | - Matthew Wheeler
- Departments of Cardiac Development and Remodeling (L.W., M.R., S.S., F.W., T.B., M.W., A.S., T.B.)
| | - Andre Schneider
- Departments of Cardiac Development and Remodeling (L.W., M.R., S.S., F.W., T.B., M.W., A.S., T.B.)
| | - Thomas Braun
- Departments of Cardiac Development and Remodeling (L.W., M.R., S.S., F.W., T.B., M.W., A.S., T.B.).,German Centre for Cardiovascular Research (DZHK), Partner site Rhein-Main, Frankfurt am Main, Germany (T.B.)
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4
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García-Padilla C, Domínguez JN, Aránega AE, Franco D. Differential chamber-specific expression and regulation of long non-coding RNAs during cardiac development. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2019; 1862:194435. [PMID: 31678627 DOI: 10.1016/j.bbagrm.2019.194435] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 09/26/2019] [Accepted: 09/27/2019] [Indexed: 12/12/2022]
Abstract
Cardiovascular development is governed by a complex interplay between inducting signals such as Bmps and Fgfs leading to activation of cardiac specific transcription factors such as Nkx2.5, Mef2c and Srf that orchestrate the initial steps of cardiogenesis. Over the last decade we have witnessed the discovery of novel layers of gene regulation, i.e. post-transcriptional regulation exerted by non-coding RNAs. The function role of small non coding RNAs has been widely demonstrated, e.g. miR-1 knockout display several cardiovascular abnormalities during embryogenesis. More recently long non-coding RNAs have been also reported to modulate gene expression and function in the developing heart, as exemplified by the embryonic lethal phenotypes of Fendrr and Braveheart knock out mice, respectively. In this study, we investigated the differential expression profile during cardiogenesis of previously reported lncRNAs in heart development. Our data revealed that Braveheart, Fendrr, Carmen display a preferential adult expression while Miat, Alien, H19 preferentially display chamber-specific expression at embryonic stages. We also demonstrated that these lncRNAs are differentially regulated by Nkx2.5, Srf and Mef2c, Pitx2 > Wnt > miRNA signaling pathway and angiotensin II and thyroid hormone administration. Importantly isoform-specific expression and distinct nuclear vs cytoplasmic localization of Braveheart, Carmen and Fendrr during chamber morphogenesis is observed, suggesting distinct functional roles of these lncRNAs in atrial and ventricular chambers. Furthermore, we demonstrate by in situ hybridization a dynamic epicardial, myocardial and endocardial expression of H19 during cardiac development. Overall our data support novel roles of these lncRNAs in different temporal and tissue-restricted fashion during cardiogenesis.
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Affiliation(s)
- Carlos García-Padilla
- Cardiovascular Development Group, Department of Experimental Biology, University of Jaen, Jaen, Spain
| | - Jorge N Domínguez
- Cardiovascular Development Group, Department of Experimental Biology, University of Jaen, Jaen, Spain
| | - Amelia E Aránega
- Cardiovascular Development Group, Department of Experimental Biology, University of Jaen, Jaen, Spain
| | - Diego Franco
- Cardiovascular Development Group, Department of Experimental Biology, University of Jaen, Jaen, Spain.
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5
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Zhang Z, Zhang Q, Lal H, Nam YJ. Generation of Nppa-tagBFP reporter knock-in mouse line for studying cardiac chamber specification. Genesis 2019; 57:e23294. [PMID: 30920727 DOI: 10.1002/dvg.23294] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 03/14/2019] [Accepted: 03/15/2019] [Indexed: 11/10/2022]
Abstract
Nppa is a cardiac hormone which plays critical roles in regulating salt-water balance. Its expression is restricted to the atria of the healthy post-natal heart. During heart development, spatio-temporal expression of Nppa is dynamically changed within the heart and becomes restricted to the atria upon birth. In contrast to its atrial specific expression after birth, Nppa is re-expressed in the adult ventricles in response to cardiac hypertrophy. To study cardiac chamber specification during development and pathological cardiac remodeling during heart disease, we generated a novel Nppa reporter mouse line by knocking-in a tagBFP reporter cassette into 3'-UTR of the Nppa gene without disrupting the endogenous gene. Our results demonstrated dynamic tagBFP expression in the developing heart, recapitulating the spatiotemporal expression pattern of endogenous Nppa. We also found that Nppa-tagBFP is induced in the ventricle during pathological remodeling. Taken together, Nppa-tagBFP reporter knock-in mouse model described in this article will serve as a valuable tool to study cardiac chamber specification during development as well as pathological cardiac remodeling.
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Affiliation(s)
- Zhentao Zhang
- Department of Medicine, Division of Cardiovascular Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee.,Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, Tennessee
| | - Qinkun Zhang
- Department of Medicine, Division of Cardiovascular Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Pharmacology, Vanderbilt University, Nashville, Tennessee
| | - Hind Lal
- Department of Medicine, Division of Cardiovascular Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Pharmacology, Vanderbilt University, Nashville, Tennessee
| | - Young-Jae Nam
- Department of Medicine, Division of Cardiovascular Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee.,Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, Tennessee
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6
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Man J, Barnett P, Christoffels VM. Structure and function of the Nppa-Nppb cluster locus during heart development and disease. Cell Mol Life Sci 2018; 75:1435-1444. [PMID: 29302701 PMCID: PMC5852170 DOI: 10.1007/s00018-017-2737-0] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 12/07/2017] [Accepted: 12/20/2017] [Indexed: 01/20/2023]
Abstract
Atrial natriuretic factor and brain natriuretic peptide are two important biomarkers in clinical cardiology. These two natriuretic peptide hormones are encoded by the paralogous genes Nppa and Nppb, which are evolutionary conserved. Both genes are predominantly expressed by the heart muscle during the embryonic and fetal stages, and in particular Nppa expression is strongly reduced in the ventricles after birth. Upon cardiac stress, Nppa and Nppb are strongly upregulated in the ventricular myocardium. Much is known about the molecular and physiological ques inducing Nppa and Nppb expression; however, the transcriptional regulatory mechanisms of the Nppa-Nppb cluster in vivo has proven to be quite complex and is not well understood. In this review, we will provide recent insights into the dynamic and complex regulation of Nppa and Nppb during heart development and hypertrophy, and the association of this gene cluster with the cardiomyocyte-intrinsic program of heart regeneration.
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Affiliation(s)
- Joyce Man
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands.
| | - Phil Barnett
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
| | - Vincent M Christoffels
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
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7
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Bruegmann T, Beiert T, Vogt CC, Schrickel JW, Sasse P. Optogenetic termination of atrial fibrillation in mice. Cardiovasc Res 2018; 114:713-723. [PMID: 29293898 DOI: 10.1093/cvr/cvx250] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 12/21/2017] [Indexed: 11/12/2022] Open
Abstract
Aims The primary goal in the treatment of symptomatic atrial fibrillation/flutter (AF) is to restore sinus rhythm by cardioversion. Electrical shocks are highly effective, but have to be applied under analgo-sedation and can further harm the heart. In order to develop a novel pain-free and less harmful approach, we explored herein the optogenetic cardioversion by light-induced depolarization. Methods and results Hearts from mice expressing Channelrhodopsin-2 (ChR2) and the AF-promoting loss-of-function Connexin 40 Ala96Ser mutation were explanted and perfused with low K+ Tyrode's solution and an atrial KATP-channel activator. This new protocol shortened atrial refractoriness as well as slowed atrial conduction and thereby enabled the induction of sustained AF. AF episodes could be terminated by epicardial illumination of the atria with focussed blue light (470 nm, 0.4 mW/mm2) with an efficacy of ∼97% (n = 17 hearts). In > 80% of cases, light directly terminated the AF episode with onset of illumination. Because similar illumination intensity was able to locally inhibit atrial activity, we propose that a light-induced block of electrical activity is responsible for reliable AF termination. The success rate was strongly depending on the illuminated area, applied light intensity and duration of illumination. Importantly, we were also able to demonstrate optogenetic termination of AF in vivo, using epicardial illumination through the open chest (n = 3 hearts). To point towards a translational potential, we systemically injected an adeno-associated virus to express ChR2 in wild type hearts. After 6-8 months, we found robust ChR2 expression in the atria, enabling light-mediated AF termination in six of seven mice tested. Conclusion We provide the first evidence for optogenetic termination of atrial tachyarrhythmia in intact hearts from transgenic as well as wild type mice ex and in vivo. Thus, this report could lay the foundation for the development of implantable devices for pain-free termination of AF.
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Affiliation(s)
- Tobias Bruegmann
- Institute of Physiology I, Medical Faculty, University of Bonn, Sigmund-Freud-Street 25, 53127 Bonn, Germany
- Research Training Group 1873, University of Bonn, Bonn, Germany
| | - Thomas Beiert
- Department of Internal Medicine II, University Hospital Bonn, University of Bonn, Bonn, Germany
| | - Christoph C Vogt
- Institute of Physiology I, Medical Faculty, University of Bonn, Sigmund-Freud-Street 25, 53127 Bonn, Germany
| | - Jan W Schrickel
- Department of Internal Medicine II, University Hospital Bonn, University of Bonn, Bonn, Germany
| | - Philipp Sasse
- Institute of Physiology I, Medical Faculty, University of Bonn, Sigmund-Freud-Street 25, 53127 Bonn, Germany
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8
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Lozano-Velasco E, Wangensteen R, Quesada A, Garcia-Padilla C, Osorio JA, Ruiz-Torres MD, Aranega A, Franco D. Hyperthyroidism, but not hypertension, impairs PITX2 expression leading to Wnt-microRNA-ion channel remodeling. PLoS One 2017; 12:e0188473. [PMID: 29194452 PMCID: PMC5711019 DOI: 10.1371/journal.pone.0188473] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 11/07/2017] [Indexed: 01/06/2023] Open
Abstract
PITX2 is a homeobox transcription factor involved in embryonic left/right signaling and more recently has been associated to cardiac arrhythmias. Genome wide association studies have pinpointed PITX2 as a major player underlying atrial fibrillation (AF). We have previously described that PITX2 expression is impaired in AF patients. Furthermore, distinct studies demonstrate that Pitx2 insufficiency leads to complex gene regulatory network remodeling, i.e. Wnt>microRNAs, leading to ion channel impairment and thus to arrhythmogenic events in mice. Whereas large body of evidences has been provided in recent years on PITX2 downstream signaling pathways, scarce information is available on upstream pathways influencing PITX2 in the context of AF. Multiple risk factors are associated to the onset of AF, such as e.g. hypertension (HTN), hyperthyroidism (HTD) and redox homeostasis impairment. In this study we have analyzed whether HTN, HTD and/or redox homeostasis impact on PITX2 and its downstream signaling pathways. Using rat models for spontaneous HTN (SHR) and experimentally-induced HTD we have observed that both cardiovascular risk factors lead to severe Pitx2 downregulation. Interesting HTD, but not SHR, leads to up-regulation of Wnt signaling as well as deregulation of multiple microRNAs and ion channels as previously described in Pitx2 insufficiency models. In addition, redox signaling is impaired in HTD but not SHR, in line with similar findings in atrial-specific Pitx2 deficient mice. In vitro cell culture analyses using gain- and loss-of-function strategies demonstrate that Pitx2, Zfhx3 and Wnt signaling influence redox homeostasis in cardiomyocytes. Thus, redox homeostasis seems to play a pivotal role in this setting, providing a regulatory feedback loop. Overall these data demonstrate that HTD, but not HTN, can impair Pitx2>>Wnt pathway providing thus a molecular link to AF.
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Affiliation(s)
- Estefanía Lozano-Velasco
- Cardiac and Skeletal Muscle Development Group, Department of Experimental Biology, University of Jaen, Jaen, Spain
| | | | - Andrés Quesada
- Department of Health Sciences, University of Jaen, Jaen, Spain
| | - Carlos Garcia-Padilla
- Cardiac and Skeletal Muscle Development Group, Department of Experimental Biology, University of Jaen, Jaen, Spain
| | - Julia A. Osorio
- Cardiac and Skeletal Muscle Development Group, Department of Experimental Biology, University of Jaen, Jaen, Spain
| | - María Dolores Ruiz-Torres
- Cardiac and Skeletal Muscle Development Group, Department of Experimental Biology, University of Jaen, Jaen, Spain
| | - Amelia Aranega
- Cardiac and Skeletal Muscle Development Group, Department of Experimental Biology, University of Jaen, Jaen, Spain
| | - Diego Franco
- Cardiac and Skeletal Muscle Development Group, Department of Experimental Biology, University of Jaen, Jaen, Spain
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9
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Ruiz-Villalba A, van Pelt-Verkuil E, Gunst QD, Ruijter JM, van den Hoff MJ. Amplification of nonspecific products in quantitative polymerase chain reactions (qPCR). BIOMOLECULAR DETECTION AND QUANTIFICATION 2017; 14:7-18. [PMID: 29255685 PMCID: PMC5727009 DOI: 10.1016/j.bdq.2017.10.001] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 10/03/2017] [Accepted: 10/05/2017] [Indexed: 10/27/2022]
Abstract
Quantitative PCR allows the precise measurement of DNA concentrations and is generally considered to be straightforward and trouble free. However, a survey with 93 validated assays for genes in the Wnt-pathway showed that the amplification of nonspecific products occurs frequently and is unrelated to Cq or PCR efficiency values. Titration experiments showed that the occurrence of low and high melting temperature artifacts was shown to be determined by annealing temperature, primer concentration and cDNA input. To explore the range of input variations that occur in the normal use of the Cre assay these conditions were mimicked in a complete two-way design of template -plasmid DNA- and non-template -mouse cDNA- concentrations. These experiments showed that the frequency of the amplification of the correct product and the artifact, as well as the valid quantification of the correct product, depended on the concentration of the non-template cDNA. This finding questions the interpretation of dilution series in which template as well as non-template concentrations are simultaneously decreasing. Repetition of this cDNA concentration experiment with other templates revealed that exact reproduction qPCR experiments was affected by the time it takes to complete the pipetting of a qPCR plate. Long bench times were observed to lead to significantly more artifacts. However, the measurement of artifact-associated fluorescence can be avoided by inclusion of a small heating step after the elongation phase in the amplification protocol. Taken together, this trouble-shooting journey showed that reliability and reproducibility of qPCR experiments not only depends on standardization and reporting of the biochemistry and technical aspects but also on hitherto neglected factors as sample dilution and waiting times in the laboratory work flow.
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Affiliation(s)
- Adrián Ruiz-Villalba
- Academic Medical Center, Department of Medical Biology, Meibergdreef 15, 1105AZ Amsterdam, The Netherlands.,Foundation of Applied Medical Research (FIMA), Area of Cell Therapy, University of Navarra, Avd Pío XII, 36 - 31008, Pamplona, Spain
| | | | - Quinn D Gunst
- Academic Medical Center, Department of Medical Biology, Meibergdreef 15, 1105AZ Amsterdam, The Netherlands
| | - Jan M Ruijter
- Academic Medical Center, Department of Medical Biology, Meibergdreef 15, 1105AZ Amsterdam, The Netherlands
| | - Maurice Jb van den Hoff
- Academic Medical Center, Department of Medical Biology, Meibergdreef 15, 1105AZ Amsterdam, The Netherlands
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10
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Shimura D, Kusakari Y, Sasano T, Nakashima Y, Nakai G, Jiao Q, Jin M, Yokota T, Ishikawa Y, Nakano A, Goda N, Minamisawa S. Heterozygous deletion of sarcolipin maintains normal cardiac function. Am J Physiol Heart Circ Physiol 2016; 310:H92-103. [DOI: 10.1152/ajpheart.00411.2015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 10/21/2015] [Indexed: 11/22/2022]
Abstract
Sarcolipin (SLN) is a small proteolipid and a regulator of sarco(endo)plasmic reticulum Ca2+-ATPase. In heart tissue, SLN is exclusively expressed in the atrium. Previously, we inserted Cre recombinase into the endogenous SLN locus by homologous recombination and succeeded in generating SLN-Cre knockin (SlnCre/+) mice. This SlnCre/+ mouse can be used to generate an atrium-specific gene-targeting mutant, and it is based on the Cre-loxP system. In the present study, we used adult SlnCre/+ mice atria and analyzed the effects of heterozygous SLN deletion by Cre knockin before use as the gene targeting mouse. Both SLN mRNA and protein levels were decreased in SlnCre/+ mouse atria, but there were no morphological, physiological, or molecular biological abnormalities. The properties of contractility and Ca2+ handling were similar to wild-type (WT) mice, and expression levels of several stress markers and sarcoplasmic reticulum-related protein levels were not different between SlnCre/+ and WT mice. Moreover, there was no significant difference in sarco(endo)plasmic reticulum Ca2+-ATPase activity between the two groups. We showed that SlnCre/+ mice were not significantly different from WT mice in all aspects that were examined. The present study provides basic characteristics of SlnCre/+ mice and possibly information on the usefulness of SlnCre/+ mice as an atrium-specific gene-targeting model.
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Affiliation(s)
- Daisuke Shimura
- Department of Life Science and Medical Bioscience, Waseda University, Tokyo, Japan
| | - Yoichiro Kusakari
- Department of Cell Physiology, The Jikei University School of Medicine, Tokyo, Japan
| | - Tetsuo Sasano
- Department of Biofunctional Informatics, Tokyo Medical and Dental University, Tokyo, Japan
| | | | - Gaku Nakai
- Department of Life Science and Medical Bioscience, Waseda University, Tokyo, Japan
| | - Qibin Jiao
- Department of Cardiology, The Affiliated Hospital of Hangzhou Normal University, Institute of Ageing Research, School of Medicine, Hangzhou Normal University, Hangzhou, China
| | - Meihua Jin
- Cardiovascular Research Institute, Yokohama City University, Kanagawa, Japan
| | - Tomohiro Yokota
- Departments of Anesthesiology, Physiology and Medicine, Molecular Biology Institute, David Geffen School of Medicine, University of California, Los Angeles, California
| | - Yoshihiro Ishikawa
- Cardiovascular Research Institute, Yokohama City University, Kanagawa, Japan
| | - Atsushi Nakano
- Department of Molecular Cell and Developmental Biology, University of California, Los Angeles, California
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, California
- Jonsson Comprehensive Cancer Center, University of California, Los Angeles, California; and
- Molecular Biology Institute, University of California, Los Angeles, California
| | - Nobuhito Goda
- Department of Life Science and Medical Bioscience, Waseda University, Tokyo, Japan
| | - Susumu Minamisawa
- Department of Life Science and Medical Bioscience, Waseda University, Tokyo, Japan
- Department of Cell Physiology, The Jikei University School of Medicine, Tokyo, Japan
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11
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Lozano-Velasco E, Hernández-Torres F, Daimi H, Serra SA, Herraiz A, Hove-Madsen L, Aránega A, Franco D. Pitx2 impairs calcium handling in a dose-dependent manner by modulating Wnt signalling. Cardiovasc Res 2016; 109:55-66. [PMID: 26243430 DOI: 10.1093/cvr/cvv207] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 07/16/2015] [Indexed: 01/02/2023] Open
Abstract
AIMS Atrial fibrillation (AF) is the most common type of arrhythmia in humans, yet the genetic cause of AF remains elusive. Genome-wide association studies (GWASs) have reported risk variants in four distinct genetic loci, and more recently, a meta-GWAS has further implicated six new loci in AF. However, the functional role of these AF GWAS-related genes in AF and their inter-relationship remain elusive. METHODS AND RESULTS To get further insights into the molecular mechanisms driven by Pitx2, calcium handling and novel AF GWAS-associated gene expression were analysed in two distinct Pitx2 loss-of-function models with distinct basal electrophysiological defects; a novel Pitx2 conditional mouse line, Sox2CrePitx2, and our previously reported atrial-specific NppaCrePitx2 line. Molecular analyses of the left atrial appendage in NppaCrePitx2(+/-) and NppaCrePitx2(-/-) adult mice demonstrate that AF GWAS-associated genes such as Zfhx3, Kcnn3, and Wnt8a are severely impaired but not Cav1, Synpo2l, nor Prrx1. In addition, multiple calcium-handling genes such as Atp2a2, Casq2, and Plb are severely altered in atrial-specific NppaCrePitx2 mice in a dose-dependent manner. Functional assessment of calcium homeostasis further underscores these findings. In addition, multiple AF-related microRNAs are also impaired. In vitro over-expression of Wnt8, but not Zfhx3, impairs calcium handling and modulates microRNA expression signature identified in Pitx2 loss-of-function models. CONCLUSION Our data demonstrate a dose-dependent relation between Pitx2 expression and the expression of AF susceptibility genes, calcium handling, and microRNAs and identify a complex regulatory network orchestrated by Pitx2 with large impact on atrial arrhythmogenesis susceptibility.
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Affiliation(s)
- Estefanía Lozano-Velasco
- Cardiovascular Development Group, Department of Experimental Biology, University of Jaén, Jaén, Spain
| | | | - Houria Daimi
- Cardiovascular Development Group, Department of Experimental Biology, University of Jaén, Jaén, Spain
| | - Selma A Serra
- Cardiac Rhythm and Contraction Group, Cardiovascular Research Centre CSIC-ICCC and IIB Sant Pau, Barcelona, Spain
| | - Adela Herraiz
- Cardiac Rhythm and Contraction Group, Cardiovascular Research Centre CSIC-ICCC and IIB Sant Pau, Barcelona, Spain
| | - Leif Hove-Madsen
- Cardiac Rhythm and Contraction Group, Cardiovascular Research Centre CSIC-ICCC and IIB Sant Pau, Barcelona, Spain
| | - Amelia Aránega
- Cardiovascular Development Group, Department of Experimental Biology, University of Jaén, Jaén, Spain
| | - Diego Franco
- Cardiovascular Development Group, Department of Experimental Biology, University of Jaén, Jaén, Spain
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12
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Davies L, Jin J, Shen W, Tsui H, Shi Y, Wang Y, Zhang Y, Hao G, Wu J, Chen S, Fraser JA, Dong N, Christoffels V, Ravens U, Huang CL, Zhang H, Cartwright EJ, Wang X, Lei M. Mkk4 is a negative regulator of the transforming growth factor beta 1 signaling associated with atrial remodeling and arrhythmogenesis with age. J Am Heart Assoc 2014; 3:e000340. [PMID: 24721794 PMCID: PMC4187508 DOI: 10.1161/jaha.113.000340] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Accepted: 01/07/2014] [Indexed: 12/19/2022]
Abstract
BACKGROUND Atrial fibrillation (AF), often associated with structural, fibrotic change in cardiac tissues involving regulatory signaling mediators, becomes increasingly common with age. In the present study, we explored the role of mitogen-activated protein kinase kinase 4 (Mkk4), a critical component of the stress-activated mitogen-activated protein kinase family, in age-associated AF. METHODS AND RESULTS We developed a novel mouse model with a selective inactivation of atrial cardiomyocyte Mkk4 (Mkk4(ACKO)). We characterized and compared electrophysiological, histological, and molecular features of young (3- to 4-month), adult (6-month), and old (1-year) Mkk4(ACKO) mice with age-matched control littermates (Mkk4(F/F)). Aging Mkk4(ACKO) mice were more susceptible to atrial tachyarrhythmias than the corresponding Mkk4(F/F) mice, showing characteristic slow and dispersed atrial conduction, for which modeling studies demonstrated potential arrhythmic effects. These differences paralleled increased interstitial fibrosis, upregulated transforming growth factor beta 1 (TGF-β1) signaling and dysregulation of matrix metalloproteinases in Mkk4(ACKO), compared to Mkk4(F/F), atria. Mkk4 inactivation increased the sensitivity of cultured cardiomyocytes to angiotensin II-induced activation of TGF-β1 signaling. This, in turn, enhanced expression of profibrotic molecules in cultured cardiac fibroblasts, suggesting cross-talk between these two cell types in profibrotic signaling. Finally, human atrial tissues in AF showed a Mkk4 downregulation associated with increased production of profibrotic molecules, compared to findings in tissue from control subjects in sinus rhythm. CONCLUSIONS These findings together demonstrate, for the first time, that Mkk4 is a negative regulator of the TGF-β1 signaling associated with atrial remodeling and arrhythmogenesis with age, establishing Mkk4 as a new potential therapeutic target for treating AF.
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Affiliation(s)
- Laura Davies
- Institute of Cardiovascular Sciences, Faculty of Medicine and Human Sciences, University of Manchester, Manchester, UK (L.D., J.J., H.T., Y.W., Y.Z., G.H., E.J.C., M.L.)
| | - Jiawei Jin
- Institute of Cardiovascular Sciences, Faculty of Medicine and Human Sciences, University of Manchester, Manchester, UK (L.D., J.J., H.T., Y.W., Y.Z., G.H., E.J.C., M.L.)
- Faculty of Life Science, University of Manchester, Manchester, UK (J.J., X.W.)
| | - Weijin Shen
- School of Physics and Astronomy, University of Manchester, Manchester, UK (W.S., H.Z.)
| | - Hoyee Tsui
- Institute of Cardiovascular Sciences, Faculty of Medicine and Human Sciences, University of Manchester, Manchester, UK (L.D., J.J., H.T., Y.W., Y.Z., G.H., E.J.C., M.L.)
| | - Ying Shi
- Institute for Cardiovascular Diseases, Union Hospital, Huazhong University of Science and Technology, Wuhan, China (Y.S., J.W., S.C., N.D., M.L.)
| | - Yanwen Wang
- Institute of Cardiovascular Sciences, Faculty of Medicine and Human Sciences, University of Manchester, Manchester, UK (L.D., J.J., H.T., Y.W., Y.Z., G.H., E.J.C., M.L.)
| | - Yanmin Zhang
- Institute of Cardiovascular Sciences, Faculty of Medicine and Human Sciences, University of Manchester, Manchester, UK (L.D., J.J., H.T., Y.W., Y.Z., G.H., E.J.C., M.L.)
| | - Guoliang Hao
- Institute of Cardiovascular Sciences, Faculty of Medicine and Human Sciences, University of Manchester, Manchester, UK (L.D., J.J., H.T., Y.W., Y.Z., G.H., E.J.C., M.L.)
| | - Jingjing Wu
- Institute for Cardiovascular Diseases, Union Hospital, Huazhong University of Science and Technology, Wuhan, China (Y.S., J.W., S.C., N.D., M.L.)
| | - Si Chen
- Institute for Cardiovascular Diseases, Union Hospital, Huazhong University of Science and Technology, Wuhan, China (Y.S., J.W., S.C., N.D., M.L.)
| | - James A. Fraser
- Physiological Laboratory, University of Cambridge, Cambridge, UK (J.A.F., C.L.H.)
| | - Nianguo Dong
- Institute for Cardiovascular Diseases, Union Hospital, Huazhong University of Science and Technology, Wuhan, China (Y.S., J.W., S.C., N.D., M.L.)
| | - Vincent Christoffels
- Department of Anatomy & Embryology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands (V.C.)
| | - Ursula Ravens
- Department of Pharmacology and Toxicology, Medical Faculty, Dresden University of Technology, Dresden, Germany (U.R.)
| | | | - Henggui Zhang
- School of Physics and Astronomy, University of Manchester, Manchester, UK (W.S., H.Z.)
| | - Elizabeth J. Cartwright
- Institute of Cardiovascular Sciences, Faculty of Medicine and Human Sciences, University of Manchester, Manchester, UK (L.D., J.J., H.T., Y.W., Y.Z., G.H., E.J.C., M.L.)
| | - Xin Wang
- Faculty of Life Science, University of Manchester, Manchester, UK (J.J., X.W.)
| | - Ming Lei
- Institute of Cardiovascular Sciences, Faculty of Medicine and Human Sciences, University of Manchester, Manchester, UK (L.D., J.J., H.T., Y.W., Y.Z., G.H., E.J.C., M.L.)
- Institute for Cardiovascular Diseases, Union Hospital, Huazhong University of Science and Technology, Wuhan, China (Y.S., J.W., S.C., N.D., M.L.)
- Department of Pharmacology, University of Oxford, Mansfield Road, UK (M.L.)
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13
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Matsuoka K, Asano Y, Higo S, Tsukamoto O, Yan Y, Yamazaki S, Matsuzaki T, Kioka H, Kato H, Uno Y, Asakura M, Asanuma H, Minamino T, Aburatani H, Kitakaze M, Komuro I, Takashima S. Noninvasive and quantitative live imaging reveals a potential stress‐responsive enhancer in the failing heart. FASEB J 2014; 28:1870-9. [DOI: 10.1096/fj.13-245522] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ken Matsuoka
- Department of Cardiovascular MedicineOsaka University Graduate School of MedicineSuitaJapan
- Department of Medical BiochemistryOsaka University Graduate School of MedicineSuitaJapan
| | - Yoshihiro Asano
- Department of Cardiovascular MedicineOsaka University Graduate School of MedicineSuitaJapan
- Department of Medical BiochemistryOsaka University Graduate School of MedicineSuitaJapan
| | - Shuichiro Higo
- Department of Cardiovascular MedicineOsaka University Graduate School of MedicineSuitaJapan
- Department of Medical BiochemistryOsaka University Graduate School of MedicineSuitaJapan
| | - Osamu Tsukamoto
- Department of Medical BiochemistryOsaka University Graduate School of MedicineSuitaJapan
| | - Yi Yan
- Department of Medical BiochemistryOsaka University Graduate School of MedicineSuitaJapan
| | - Satoru Yamazaki
- Department of Cell BiologyNational Cerebral and Cardiovascular Center Research InstituteSuitaJapan
| | - Takashi Matsuzaki
- Department of Cardiovascular MedicineOsaka University Graduate School of MedicineSuitaJapan
| | - Hidetaka Kioka
- Department of Cardiovascular MedicineOsaka University Graduate School of MedicineSuitaJapan
- Department of Medical BiochemistryOsaka University Graduate School of MedicineSuitaJapan
| | - Hisakazu Kato
- Department of Medical BiochemistryOsaka University Graduate School of MedicineSuitaJapan
| | - Yoshihiro Uno
- Laboratory of Reproductive EngineeringInstitute of Experimental Animal Sciences, Osaka University Graduate School of MedicineSuitaJapan
| | - Masanori Asakura
- Department of Clinical Research and DevelopmentNational Cerebral and Cardiovascular Center Research InstituteSuitaJapan
| | - Hiroshi Asanuma
- Department of Cardiovascular Science and TechnologyKyoto Prefectural University School of MedicineKyotoJapan
| | - Tetsuo Minamino
- Department of Cardiovascular MedicineOsaka University Graduate School of MedicineSuitaJapan
| | - Hiroyuki Aburatani
- Genome Science Division, Research Center for Advanced Science and TechnologyUniversity of TokyoTokyoJapan
| | - Masafumi Kitakaze
- Department of Clinical Research and DevelopmentNational Cerebral and Cardiovascular Center Research InstituteSuitaJapan
| | - Issei Komuro
- Department of Cardiovascular MedicineOsaka University Graduate School of MedicineSuitaJapan
| | - Seiji Takashima
- Department of Cardiovascular MedicineOsaka University Graduate School of MedicineSuitaJapan
- Department of Medical BiochemistryOsaka University Graduate School of MedicineSuitaJapan
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14
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Tbx2 and Tbx3 induce atrioventricular myocardial development and endocardial cushion formation. Cell Mol Life Sci 2011; 69:1377-89. [PMID: 22130515 PMCID: PMC3314179 DOI: 10.1007/s00018-011-0884-2] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Revised: 10/25/2011] [Accepted: 11/07/2011] [Indexed: 11/03/2022]
Abstract
A key step in heart development is the coordinated development of the atrioventricular canal (AVC), the constriction between the atria and ventricles that electrically and physically separates the chambers, and the development of the atrioventricular valves that ensure unidirectional blood flow. Using knock-out and inducible overexpression mouse models, we provide evidence that the developmentally important T-box factors Tbx2 and Tbx3, in a functionally redundant manner, maintain the AVC myocardium phenotype during the process of chamber differentiation. Expression profiling and ChIP-sequencing analysis of Tbx3 revealed that it directly interacts with and represses chamber myocardial genes, and induces the atrioventricular pacemaker-like phenotype by activating relevant genes. Moreover, mutant mice lacking 3 or 4 functional alleles of Tbx2 and Tbx3 failed to form atrioventricular cushions, precursors of the valves and septa. Tbx2 and Tbx3 trigger development of the cushions through a regulatory feed-forward loop with Bmp2, thus providing a mechanism for the co-localization and coordination of these important processes in heart development.
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15
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Chinchilla A, Daimi H, Lozano-Velasco E, Dominguez JN, Caballero R, Delpón E, Tamargo J, Cinca J, Hove-Madsen L, Aranega AE, Franco D. PITX2 insufficiency leads to atrial electrical and structural remodeling linked to arrhythmogenesis. CIRCULATION. CARDIOVASCULAR GENETICS 2011; 4:269-79. [PMID: 21511879 DOI: 10.1161/circgenetics.110.958116] [Citation(s) in RCA: 189] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Pitx2 is a homeobox transcription factor that plays a pivotal role in early left/right determination during embryonic development. Pitx2 loss-of-function mouse mutants display early embryonic lethality with severe cardiac malformations, demonstrating the importance of Pitx2 during cardiogenesis. Recently, independent genome-wide association studies have provided new evidence for a putative role of PITX2 in the adult heart. These studies have independently reported several risk variants close to the PITX2 locus on chromosome 4q25 that are strongly associated with atrial fibrillation in humans. METHODS AND RESULTS We show for the first time that PITX2C expression is significantly decreased in human patients with sustained atrial fibrillation, thus providing a molecular link between PITX2 loss of function and atrial fibrillation. In addition, morphological, molecular, and electrophysiological characterization of chamber-specific Pitx2 conditional mouse mutants reveals that atrial but not ventricular chamber-specific deletion of Pitx2 results in differences in the action potential amplitude and resting membrane potential in the adult heart as well as ECG characteristics of atrioventricular block. Lack of Pitx2 in atrial myocardium impairs sodium channel and potassium channel expression, mediated in part by miRNA misexpression. CONCLUSIONS This study thus identifies Pitx2 as an upstream transcriptional regulator of atrial electric function, the insufficiency of which results in cellular and molecular changes leading to atrial electric and structural remodeling linked to arrhythmogenesis.
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Affiliation(s)
- Ana Chinchilla
- Department of Experimental Biology, University of Jaén, Jaén, Spain
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16
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Lozano-Velasco E, Chinchilla A, Martínez-Fernández S, Hernández-Torres F, Navarro F, Lyons GE, Franco D, Aránega AE. Pitx2c modulates cardiac-specific transcription factors networks in differentiating cardiomyocytes from murine embryonic stem cells. Cells Tissues Organs 2011; 194:349-62. [PMID: 21389672 DOI: 10.1159/000323533] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/13/2010] [Indexed: 02/02/2023] Open
Abstract
AIM The knowledge of the molecular signals that control cell differentiation into cardiomyocytes is critical to apply cell-based therapies and repair an injured heart. The transcription factor Pitx2 has essential roles in the development of different organs including the heart. Although a direct role of Pitx2 in the developing myocardium has recently been reported, the molecular pathways driven by Pitx2 as well as its cardiac target genes remain largely unexplored. The aim of this study was to unravel the molecular mechanisms driven by Pitx2 during the process of cardiomyocyte differentiation in vitro in mouse embryonic stem cell-derived cardiomyocytes. METHODS AND RESULTS Pitx2c was overexpressed in the R1-embryonic stem cell line. mRNA levels and protein distribution of several specific cardiac genes were analyzed by real-time PCR and immunohistochemistry experiments in R1-embryonic stem cell-derived beating areas at different stages of in vitro differentiation. Our results show that overexpression of Pitx2c in embryonic stem cell-derived cardiomyocytes is able to dynamically upregulate several cardiac-enriched transcription factors such as Isl1, Mef2c and Gata4. Additionally, Pitx2c induces the expression of chamber-specific cardiac genes such as Tbx5, Nppa and Cx40. These data were validated in an in vivo model of Pitx2 loss of function. CONCLUSION Taken together, these results demonstrate that Pitx2 plays a major role reinforcing the transcriptional program of cardiac differentiation.
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17
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González-Rosa JM, Padrón-Barthe L, Torres M, Mercader N. [Lineage tracing of epicardial cells during development and regeneration]. Rev Esp Cardiol 2010; 63 Suppl 2:36-48. [PMID: 20540899 DOI: 10.1016/s0300-8932(10)70151-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Tracing the history of individual cells during embryonic morphogenesis in a structure as complex as the cardiovascular system is one of the major challenges of developmental biology. It involves determining the relationships between the various lineages of cells forming an organ at different stages, describing the topological rearrangements tissues undergo during morphogenesis, and characterizing the interactions between cells in different structures. However, despite the great expectations raised in the field of regenerative medicine, only limited progress has been made in using regenerative therapy to repair the cardiovascular system. Recent research has highlighted the role of the epicardium during cardiac regeneration, but it is still unclear whether it is important for molecular signaling or acts as a source of progenitor cells during this process. Consequently, increasing knowledge about the origin, diversification and potential of epicardial cells during development and homeostasis and under pathological conditions is of fundamental importance both for basic research and for the development of effective cellular therapies. The aims of this article were to provide a general overview of the classical techniques used for tracing cell lineages, including their potential and limitations, and to describe novel techniques for studying the origin and differentiation of the epicardium and its role in cardiac regeneration.
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Affiliation(s)
- Juan Manuel González-Rosa
- Departamento de Biología del Desarrollo Cardiovascular, Centro Nacional de Investigaciones Cardiovasculares, Instituto de Salud Carlos III, Madrid, España
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18
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Wiese C, Grieskamp T, Airik R, Mommersteeg MTM, Gardiwal A, de Gier-de Vries C, Schuster-Gossler K, Moorman AFM, Kispert A, Christoffels VM. Formation of the sinus node head and differentiation of sinus node myocardium are independently regulated by Tbx18 and Tbx3. Circ Res 2009; 104:388-97. [PMID: 19096026 DOI: 10.1161/circresaha.108.187062] [Citation(s) in RCA: 225] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The sinus node (or sinoatrial node [SAN]), the pacemaker of the heart, is a functionally and structurally heterogeneous tissue, which consists of a large "head" within the right caval vein myocardium and a "tail" along the terminal crest. Here, we investigated its cellular origin and mechanism of formation. Using genetic lineage analysis and explant assays, we identified T-box transcription factor Tbx18-expressing mesenchymal progenitors in the inflow tract region that differentiate into pacemaker myocardium to form the SAN. We found that the head and tail represent separate regulatory domains expressing distinctive gene programs. Tbx18 is required to establish the large head structure, as seen by the existence of a very small but still functional tail piece in Tbx18-deficient fetuses. In contrast, Tbx3-deficient embryos formed a morphologically normal SAN, which, however, aberrantly expressed Cx40 and other atrial genes, demonstrating that Tbx3 controls differentiation of SAN head and tail cardiomyocytes but also demonstrating that Tbx3 is not required for the formation of the SAN structure. Our data establish a functional order for Tbx18 and Tbx3 in SAN formation, in which Tbx18 controls the formation of the SAN head from mesenchymal precursors, on which Tbx3 subsequently imposes the pacemaker gene program.
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Affiliation(s)
- Cornelia Wiese
- Center for Heart Failure Research, Academic Medical Centre, Meibergdreef 15, 1105AZ Amsterdam, The Netherlands
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19
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Horsthuis T, Houweling AC, Habets PE, de Lange FJ, el Azzouzi H, Clout DE, Moorman AF, Christoffels VM. Distinct Regulation of Developmental and Heart Disease–Induced Atrial Natriuretic Factor Expression by Two Separate Distal Sequences. Circ Res 2008; 102:849-59. [DOI: 10.1161/circresaha.107.170571] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Nppa
, encoding atrial natriuretic factor, is expressed in fetal atrial and ventricular myocardium and is downregulated in the ventricles after birth. During hypertrophy and heart failure,
Nppa
expression is reactivated in the ventricles and serves as a highly conserved marker of heart disease. The
Nppa
promoter has become a frequently used model to study mechanisms of cardiac gene regulation. Nevertheless, the regulatory sequences that provide the correct developmental pattern and ventricular reactivation during cardiac disease remain to be defined. We found that proximal
Nppa
fragments ranging from 250 bp to 16 kbp provide robust reporter gene activity in the atria and correct repression in the atrioventricular canal and the nodes of the conduction system in vivo. However, depending on fragment size and site of integration into the genome of mice, the fetal ventricular activity was either absent or present in an incorrect pattern. Furthermore, these fragments did not provide ventricular reactivation in heart disease models. These results indicate that the proximal promoter does not provide a physiologically relevant model for ventricular gene activity. In contrast, 2 modified bacterial artificial chromosome clones with partially overlapping genomic
Nppa
sequences provided appropriate reactivation of the green fluorescent protein reporter during pressure overload–induced hypertrophy and heart failure in vivo. However, only 1 of these bacterial artificial chromosomes provided correct fetal ventricular green fluorescent protein activity. These results show that distinct distal regulatory sequences and divergent regulatory pathways control fetal ventricular activity and reactivation of
Nppa
during cardiac disease, respectively.
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Affiliation(s)
- Thomas Horsthuis
- From the Heart Failure Research Center (T.H., A.C.H., P.E.M.H.H, F.J.d.L., D.E.W.C., A.F.M.M., V.M.C.), Academic Medical Center, University of Amsterdam; and the Hubrecht Institute and Interuniversity Cardiology Institute Netherlands (H.e.A.), Royal Netherlands Academy of Sciences, Utrecht, the Netherlands
| | - Arjan C. Houweling
- From the Heart Failure Research Center (T.H., A.C.H., P.E.M.H.H, F.J.d.L., D.E.W.C., A.F.M.M., V.M.C.), Academic Medical Center, University of Amsterdam; and the Hubrecht Institute and Interuniversity Cardiology Institute Netherlands (H.e.A.), Royal Netherlands Academy of Sciences, Utrecht, the Netherlands
| | - Petra E.M.H. Habets
- From the Heart Failure Research Center (T.H., A.C.H., P.E.M.H.H, F.J.d.L., D.E.W.C., A.F.M.M., V.M.C.), Academic Medical Center, University of Amsterdam; and the Hubrecht Institute and Interuniversity Cardiology Institute Netherlands (H.e.A.), Royal Netherlands Academy of Sciences, Utrecht, the Netherlands
| | - Frederik J. de Lange
- From the Heart Failure Research Center (T.H., A.C.H., P.E.M.H.H, F.J.d.L., D.E.W.C., A.F.M.M., V.M.C.), Academic Medical Center, University of Amsterdam; and the Hubrecht Institute and Interuniversity Cardiology Institute Netherlands (H.e.A.), Royal Netherlands Academy of Sciences, Utrecht, the Netherlands
| | - Hamid el Azzouzi
- From the Heart Failure Research Center (T.H., A.C.H., P.E.M.H.H, F.J.d.L., D.E.W.C., A.F.M.M., V.M.C.), Academic Medical Center, University of Amsterdam; and the Hubrecht Institute and Interuniversity Cardiology Institute Netherlands (H.e.A.), Royal Netherlands Academy of Sciences, Utrecht, the Netherlands
| | - Danielle E.W. Clout
- From the Heart Failure Research Center (T.H., A.C.H., P.E.M.H.H, F.J.d.L., D.E.W.C., A.F.M.M., V.M.C.), Academic Medical Center, University of Amsterdam; and the Hubrecht Institute and Interuniversity Cardiology Institute Netherlands (H.e.A.), Royal Netherlands Academy of Sciences, Utrecht, the Netherlands
| | - Antoon F.M. Moorman
- From the Heart Failure Research Center (T.H., A.C.H., P.E.M.H.H, F.J.d.L., D.E.W.C., A.F.M.M., V.M.C.), Academic Medical Center, University of Amsterdam; and the Hubrecht Institute and Interuniversity Cardiology Institute Netherlands (H.e.A.), Royal Netherlands Academy of Sciences, Utrecht, the Netherlands
| | - Vincent M. Christoffels
- From the Heart Failure Research Center (T.H., A.C.H., P.E.M.H.H, F.J.d.L., D.E.W.C., A.F.M.M., V.M.C.), Academic Medical Center, University of Amsterdam; and the Hubrecht Institute and Interuniversity Cardiology Institute Netherlands (H.e.A.), Royal Netherlands Academy of Sciences, Utrecht, the Netherlands
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20
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Mommersteeg MTM, Brown NA, Prall OWJ, de Gier-de Vries C, Harvey RP, Moorman AFM, Christoffels VM. Pitx2c and Nkx2-5 are required for the formation and identity of the pulmonary myocardium. Circ Res 2007; 101:902-9. [PMID: 17823370 DOI: 10.1161/circresaha.107.161182] [Citation(s) in RCA: 271] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The pulmonary vein is sleeved by myocardium, which is a major source of atrial fibrillation and is involved in congenital sinus venosus defects. Little is known about the cellular origin and mechanism of formation of the pulmonary myocardium. We observed a biphasic process of pulmonary myocardium formation in mice. Firstly, a myocardial cell population forms de novo at the connection of the pulmonary vein and the atrium. Genetic labeling revealed that atrial cells do not contribute to this population, indicating it forms by differentiation of pulmonary mesenchymal cells. Secondly, these pulmonary myocardial cells initiate a phase of rapid proliferation and form the pulmonary myocardial sleeve. Pitx2c-deficient mice do not develop a pulmonary myocardial sleeve because they fail to form the initial pulmonary myocardial cells. Genetic-labeling analyses demonstrated that whereas the systemic venous return derives from Nkx2-5-negative precursors, the pulmonary myocardium derives from Nkx2-5-expressing precursors, indicating a distinct origin of the 2 venous systems. Nkx2-5 and its target gap-junction gene Cx40 are expressed in the atria and in the pulmonary myocardium but not in the systemic venous return, which expresses the essential pacemaker channel Hcn4. When Nkx2-5 protein level was lowered in a hypomorphic model, the pulmonary myocardium switched to a Cx40-negative, Hcn4-positive phenotype resembling that of the systemic venous return. In conclusion, our data suggest a cellular mechanism for pulmonary myocardium formation and highlight the key roles played by Pitx2c and Nkx2-5 in its formation and identity.
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Affiliation(s)
- Mathilda T M Mommersteeg
- Heart Failure Research Center, Academic Medical Centre, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
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21
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Hoogaars WM, Engel A, Brons JF, Verkerk AO, de Lange FJ, Wong LE, Bakker ML, Clout DE, Wakker V, Barnett P, Ravesloot JH, Moorman AF, Verheijck EE, Christoffels VM. Tbx3 controls the sinoatrial node gene program and imposes pacemaker function on the atria. Genes Dev 2007; 21:1098-112. [PMID: 17473172 PMCID: PMC1855235 DOI: 10.1101/gad.416007] [Citation(s) in RCA: 296] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The sinoatrial node initiates the heartbeat and controls the rate and rhythm of contraction, thus serving as the pacemaker of the heart. Despite the crucial role of the sinoatrial node in heart function, the mechanisms that underlie its specification and formation are not known. Tbx3, a transcriptional repressor required for development of vertebrates, is expressed in the developing conduction system. Here we show that Tbx3 expression delineates the sinoatrial node region, which runs a gene expression program that is distinct from that of the bordering atrial cells. We found lineage segregation of Tbx3-negative atrial and Tbx3-positive sinoatrial node precursor cells as soon as cardiac cells turn on the atrial gene expression program. Tbx3 deficiency resulted in expansion of expression of the atrial gene program into the sinoatrial node domain, and partial loss of sinoatrial node-specific gene expression. Ectopic expression of Tbx3 in mice revealed that Tbx3 represses the atrial phenotype and imposes the pacemaker phenotype on the atria. The mice displayed arrhythmias and developed functional ectopic pacemakers. These data identify a Tbx3-dependent pathway for the specification and formation of the sinoatrial node, and show that Tbx3 regulates the pacemaker gene expression program and phenotype.
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Affiliation(s)
- Willem M.H. Hoogaars
- Department of Anatomy and Embryology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Angela Engel
- Department of Physiology, Heart Failure Research Center, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Janynke F. Brons
- Department of Anatomy and Embryology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Arie O. Verkerk
- Department of Physiology, Heart Failure Research Center, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Frederik J. de Lange
- Department of Anatomy and Embryology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - L.Y. Elaine Wong
- Department of Anatomy and Embryology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Martijn L. Bakker
- Department of Anatomy and Embryology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Danielle E. Clout
- Department of Anatomy and Embryology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Vincent Wakker
- Department of Anatomy and Embryology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Phil Barnett
- Department of Anatomy and Embryology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Jan Hindrik Ravesloot
- Department of Physiology, Heart Failure Research Center, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Antoon F.M. Moorman
- Department of Anatomy and Embryology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - E. Etienne Verheijck
- Department of Physiology, Heart Failure Research Center, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Vincent M. Christoffels
- Department of Anatomy and Embryology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Corresponding author.E-MAIL ; FAX 31-20-6976177
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22
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Breckenridge R, Kotecha S, Towers N, Bennett M, Mohun T. Pan-myocardial expression of Cre recombinase throughout mouse development. Genesis 2007; 45:135-44. [PMID: 17334998 DOI: 10.1002/dvg.20275] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Mouse-lines expressing Cre recombinase in a tissue-specific manner are a powerful tool in developmental biology. Here, we report that a 3 kb fragment of the Xenopus laevis myosin light-chain 2 (XMLC2) promoter drives Cre recombinase expression in a cardiac-restricted fashion in the mouse embryo. We have isolated two XMLC2-Cre lines that express recombinase exclusively within cardiomyocytes, from the onset of their differentiation in the cardiac crescent of the early embryo. Expression is maintained throughout the myocardium of the embryonic heart tube and subsequently the mature myocardium of the chambered heart. Recombinase activity is detected in all myocardial tissue, including the pulmonary veins. One XMLC2-Cre line shows uniform expression while the other only expresses recombinase in a mosaic fashion encompassing less than 50% of the myocardial cells. Both lines cause severe cardiac malformations when crossed to a conditional Tbx5 line, resulting in embryonic death at midgestation. Optical projection tomography reveals that the spectrum of developmental abnormalities includes a shortening of the outflow tract and its abnormal alignment, along with a dramatic reduction in trabeculation of the ventricular segment of the looping heart tube.
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Affiliation(s)
- Ross Breckenridge
- Division of Developmental Biology, MRC National Institute for Medical Research, The Ridgeway, Mill Hill,London, United Kingdom
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23
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Christoffels VM, Mommersteeg MTM, Trowe MO, Prall OWJ, de Gier-de Vries C, Soufan AT, Bussen M, Schuster-Gossler K, Harvey RP, Moorman AFM, Kispert A. Formation of the venous pole of the heart from an Nkx2-5-negative precursor population requires Tbx18. Circ Res 2006; 98:1555-63. [PMID: 16709898 DOI: 10.1161/01.res.0000227571.84189.65] [Citation(s) in RCA: 206] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The venous pole of the mammalian heart is a structurally and electrically complex region, yet the lineage and molecular mechanisms underlying its formation have remained largely unexplored. In contrast to classical studies that attribute the origin of the myocardial sinus horns to the embryonic venous pole, we find that the sinus horns form only after heart looping by differentiation of mesenchymal cells of the septum transversum region into myocardium. The myocardial sinus horns and their mesenchymal precursor cells never express Nkx2-5, a transcription factor critical for heart development. In addition, lineage studies show that the sinus horns do not derive from cells previously positive for Nkx2-5. In contrast, the sinus horns express the T-box transcription factor gene Tbx18. Mice deficient for Tbx18 fail to form sinus horns from the pericardial mesenchyme and have defective caval veins, whereas the pulmonary vein and atrial structures are unaffected. Our studies define a novel heart precursor population that contributes exclusively to the myocardium surrounding the sinus horns or systemic venous tributaries of the developing heart, which are a source of congenital malformation and cardiac arrhythmias.
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Affiliation(s)
- Vincent M Christoffels
- Department of Experimental and Molecular Cardiology Group, Academic Medical Center, Amsterdam, The Netherlands.
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24
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Gordon KH, Sherr PC. The adolescent orphan in literature a bibliography for the study of the adolescent. J Am Psychoanal Assoc 1974; 22:537-41. [PMID: 4616981 DOI: 10.1177/000306517402200304] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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