Epicardium-derived progenitor cells require -catenin for coronary artery formation

Development and Aging Program, Burnham Institute for Medical Research, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 12/2007; 104(46):18109-14. DOI: 10.1073/pnas.0702415104
Source: PubMed


We have previously identified several members of the Wnt/beta-catenin pathway that are differentially expressed in a mouse model with deficient coronary vessel formation. Systemic ablation of beta-catenin expression affects mouse development at gastrulation with failure of both mesoderm development and axis formation. To circumvent this early embryonic lethality and study the specific role of beta-catenin in coronary arteriogenesis, we have generated conditional beta-catenin-deletion mutant animals in the proepicardium by interbreeding with a Cre-expressing mouse that targets coronary progenitor cells in the proepicardium and its derivatives. Ablation of beta-catenin in the proepicardium results in lethality between embryonic day 15 and birth. Mutant mice display impaired coronary artery formation, whereas the venous system and microvasculature are normal. Analysis of proepicardial beta-catenin mutant cells in the context of an epicardial tracer mouse reveals that the formation of the proepicardium, the migration of proepicardial cells to the heart, and the formation of the primitive epicardium are unaffected. However, subsequent processes of epicardial development are dramatically impaired in epicardial-beta-catenin mutant mice, including failed expansion of the subepicardial space, blunted invasion of the myocardium, and impaired differentiation of epicardium-derived mesenchymal cells into coronary smooth muscle cells. Our data demonstrate a functional role of the epicardial beta-catenin pathway in coronary arteriogenesis.

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Available from: Pilar ruiz-lozano, Mar 20, 2015
    • "These experiments have paved the way to the current understanding that the epicardial cells, which undergo epithelial to mesenchymal transition (EMT) and migrate to the subepicardial space. Subsequently, these epicardially-derived cells (EPDCs) differentiate into coronary smooth muscle cells, perivascular fibroblasts and interstitial fibroblasts [9] [10] [11] [12] [13]. "
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    ABSTRACT: During embryogenesis, hematopoietic cells appear in the myocardium prior to the initiation of coronary formation. However, their role is unknown. Here we investigate whether pre-existing hematopoietic cells are required for the formation of coronary vasculature. As a model of for hematopoietic cell deficient animals, we used Runx1 knockout embryos and Vav1-cre; R26-DTA embryos, latter of which genetically ablates 2/3 of CD45(+) hematopoietic cells. Both Runx1 knockout embryos and Vav1-cre; R26-DTA embryos revealed disorganized, hypoplastic microvasculature of coronary vessels on section and whole-mount stainings. Furthermore, coronary explant experiments showed that the mouse heart explants from Runx1 and Vav1-cre; R26-DTA embryos exhibited impaired coronary formation ex vivo. Interestingly, in both models it appears that epicardial to mesenchymal transition is adversely affected in the absence of hematopoietic progenitors. Hematopoietic cells are not merely passively transported via coronary vessel, but substantially involved in the induction of the coronary growth. Our findings suggest a novel mechanism of coronary growth. Copyright © 2015. Published by Elsevier Ltd.
    No preview · Article · Aug 2015 · Journal of Molecular and Cellular Cardiology
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    • "Other studies placed Wt1 upstream of epicardial Raldh2 (a key molecule in RA metabolism ) expression (Guadix et al. 2011). RA signaling in turn has been described earlier to spearhead a signaling network that includes cross talk with Wnt and FGF signaling molecules (Fig. 3C) (Merki et al. 2005; Lavine et al. 2006; Zamora et al. 2007). Formation of the coronary vessels is tightly linked to compact zone growth and relies on overlapping signaling molecules (Olivey and Svensson 2010; Perez-Pomares and de la Pompa 2011). "
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    ABSTRACT: The mammalian heart is a highly specialized organ, comprised of many different cell types arising from distinct embryonic progenitor populations during cardiogenesis. Three precursor populations have been identified to contribute to different myocytic and nonmyocytic cell lineages of the heart: cardiogenic mesoderm cells (CMC), the proepicardium (PE), and cardiac neural crest cells (CNCCs). This review will focus on molecular cues necessary for proper induction, expansion, and lineage-specific differentiation of these progenitor populations during cardiac development in vivo. Moreover, we will briefly discuss how the knowledge gained on embryonic heart progenitor biology can be used to develop novel therapeutic strategies for the management of congenital heart disease as well as for improvement of cardiac function in ischemic heart disease.
    Full-text · Article · Oct 2013 · Cold Spring Harbor Perspectives in Medicine
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    • "For an epicardial progenitor to contribute as a cell source for myocardial regeneration, the epicardial cell must initially undergo an epithelial to mesenchymal transition (EMT); i.e. the epicardial cells must first lose their “epithelial-like” characteristics and migrate into the myocardium. β-catenin has been shown to be essential for normal epicardial EMT [35]. Accordingly, our results imply that ICG-001, by specifically interfering with β-catenin/CBP transcription, promotes EMT and increases the differentiation of epicardial progenitor cells, thereby contributing to the regeneration process after myocardial infarction. "
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    ABSTRACT: The adult mammalian heart has limited capability for self-repair after myocardial infarction. Therefore, therapeutic strategies that improve post-infarct cardiac function are critically needed. The small molecule ICG-001 modulates Wnt signaling and increased the expression of genes beneficial for cardiac regeneration in epicardial cells. Lineage tracing experiments, demonstrated the importance of β-catenin/p300 mediated transcription for epicardial progenitor contribution to the myocardium. Female rats given ICG-001 for 10 days post-occlusion significantly improved ejection fraction by 8.4%, compared to controls (P<0.05). Taken together, Wnt modulation via β-catenin/CBP inhibition offers a promising therapeutic strategy towards restoration of myocardial tissues and an enhancement of cardiac functions following infarction.
    Preview · Article · Sep 2013 · PLoS ONE
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