Endothelial pyruvate kinase M2 maintains vascular integrity.
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ABSTRACT:
SUBMITTER: Kim B
PROVIDER: S-EPMC6159968 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Dilated cardiomyopathy is a frequently occurring human disease compromising heart function and a major cause of cardiac death. The causes of cardiomyopathies are often unknown. There is increasing evidence indicating that endothelial cells lining blood vessels control the homeostasis of various organs, but the special properties and functional roles of the vasculature in the adult heart maintain remain little understood. Here, we have used mouse genetics, imaging and cell biology approaches to investigate how vascular homeostasis in the adult heart is controlled by EphB4 and its ligand ephrin-B2, which are known regulators of sprouting angiogenesis, vascular morphogenesis and arteriovenous differentiation during development. We show that inducible and endothelial cell-specific inactivation of the Ephb4 gene in adult mice is compatible with survival, but leads to rupturing of cardiac capillaries, cardiomyocyte hypertrophy, and pathological cardiac remodelling. In contrast, EphB4 is not required for the integrity and homeostatic function of capillaries in skeletal muscle. Our analysis of mutant mice and cultured endothelial cells shows that EphB4 controls the function of caveolae, cell-cell adhesion under mechanical stress and lipid transport. Together, our findings establish that EphB4 maintains critical functional properties of the adult cardiac vasculature and thereby prevents dilated cardiomyopathy-like defects.
2019-11-20 | PXD012575 | Pride
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