| Autor: |
Mele L; Molecular Biology Development and Disease, UCL Institute of Cardiovascular Science, London, UK., Maskell LJ; Molecular Biology Development and Disease, UCL Institute of Cardiovascular Science, London, UK., Stuckey DJ; Centre for Advanced Biomedical Imaging (CABI), Division of Medicine, UCL Faculty of Medical Sciences, London, UK., Clark JE; School of Cardiovascular Medicine and Sciences, Faculty of Life Sciences and Medicine, King's College, London, UK., Heads RJ; School of Cardiovascular Medicine and Sciences, Faculty of Life Sciences and Medicine, King's College, London, UK., Budhram-Mahadeo VS; Molecular Biology Development and Disease, UCL Institute of Cardiovascular Science, London, UK. v.budhram-mahadeo@ucl.ac.uk. |
| Jazyk: |
angličtina |
| Zdroj: |
Cell death & disease [Cell Death Dis] 2019 Aug 14; Vol. 10 (8), pp. 621. Date of Electronic Publication: 2019 Aug 14. |
| DOI: |
10.1038/s41419-019-1848-y |
| Abstrakt: |
Adult hearts respond to increased workload such as prolonged stress or injury, by undergoing hypertrophic growth. During this process, the early adaptive responses are important for maintaining cardiac output whereas at later stages, pathological responses such as cardiomyocyte apoptosis and fibrosis cause adverse remodelling, that can progress to heart failure. Yet the factors that control transition from adaptive responses to pathological remodelling in the heart are not well understood. Here we describe the POU4F2/Brn-3b transcription factor (TF) as a novel regulator of adaptive hypertrophic responses in adult hearts since Brn-3b mRNA and protein are increased in angiotensin-II (AngII) treated mouse hearts with concomitant hypertrophic changes [increased heart weight:body weight (HW:BW) ratio]. These effects occur specifically in cardiomyocytes because Brn-3b expression is increased in AngII-treated primary cultures of neonatal rat ventricular myocytes (NRVM) or foetal heart-derived H9c2 cells, which undergo characteristic sarcomeric re-organisation seen in hypertrophic myocytes and express hypertrophic markers, ANP/βMHC. The Brn-3b promoter is activated by known hypertrophic signalling pathways e.g. p42/p44 mitogen-activated protein kinase (MAPK/ERK1/2) or calcineurin (via NFAT). Brn-3b target genes, e.g. cyclin D1, GLUT4 and Bax, are increased at different stages following AngII treatment, supporting distinct roles in cardiac responses to stress. Furthermore, hearts from male Brn-3b KO mutant mice display contractile dysfunction at baseline but also attenuated hypertrophic responses to AngII treatment. Hearts from AngII-treated male Brn-3b KO mice develop further contractile dysfunction linked to extensive fibrosis/remodelling. Moreover, known Brn-3b target genes, e.g. GLUT4, are reduced in AngII-treated Brn-3b KO hearts, suggesting that Brn-3b and its target genes are important in driving adaptive hypertrophic responses in stressed heart. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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