Glucocorticoids promote structural and functional maturation of foetal cardiomyocytes: a role for PGC-1α

Rog-Zielinska, E.A. et al. (2015) Glucocorticoids promote structural and functional maturation of foetal cardiomyocytes: a role for PGC-1α. Cell Death and Differentiation, 22(7), pp. 1106-1116. (doi: 10.1038/cdd.2014.181) (PMID:25361084) (PMCID:PMC4572859)

Abstract

Glucocorticoid levels rise dramatically in late gestation to mature foetal organs in readiness for postnatal life. Immature heart function may compromise survival. Cardiomyocyte glucocorticoid receptor (GR) is required for the structural and functional maturation of the foetal heart in vivo, yet the molecular mechanisms are largely unknown. Here we asked if GR activation in foetal cardiomyocytes in vitro elicits similar maturational changes. We show that physiologically relevant glucocorticoid levels improve contractility of primary-mouse-foetal cardiomyocytes, promote Z-disc assembly and the appearance of mature myofibrils, and increase mitochondrial activity. Genes induced in vitro mimic those induced in vivo and include PGC-1α, a critical regulator of cardiac mitochondrial capacity. SiRNA-mediated abrogation of the glucocorticoid induction of PGC-1α in vitro abolished the effect of glucocorticoid on myofibril structure and mitochondrial oxygen consumption. Using RNA sequencing we identified a number of transcriptional regulators, including PGC-1α, induced as primary targets of GR in foetal cardiomyocytes. These data demonstrate that PGC-1α is a key mediator of glucocorticoid-induced maturation of foetal cardiomyocyte structure and identify other candidate transcriptional regulators that may play critical roles in the transition of the foetal to neonatal heart.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Smith, Professor Godfrey
• Authors: Rog-Zielinska, E.A., Craig, M.-A., Manning, J.R., Richardson, R.V., Gowans, G.J., Dunbar, D.R., Gharbi, K., Kenyon, C.J., Holmes, M.C., Hardie, D.G., Smith, G.L., and Chapman, K.E.
• College/School: College of Medical Veterinary and Life Sciences > School of Cardiovascular & Metabolic Health
• Journal Name: Cell Death and Differentiation
• Publisher: Springer Nature
• ISSN: 1350-9047
• ISSN (Online): 1476-5403
• Published Online: 31 October 2014
• Copyright Holders: Copyright © 2015 Macmillan Publishers Limited
• First Published: First published in Cell Death and Differentiation 22(7):1106-1116
• Publisher Policy: Reproduced under a Creative Commons license