Item Type: | Article |
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Title: | Adipocyte fatty acid-binding protein suppresses cardiomyocyte contraction. A new link between obesity and heart disease |
Creators Name: | Lamounier-Zepter, V., Look, C., Alvarez, J., Christ, T., Ravens, U., Schunck, W.H., Ehrhart-Bornstein, M., Bornstein, S.R. and Morano, I. |
Abstract: | Rationale: Adipocyte fatty acid-binding protein (FABP4) is a member of the intracellular lipid-binding protein family and is predominantly expressed in adipose tissue. Emerging evidence suggests that FABP4 plays a role in some aspects of the metabolic syndrome including the development of type 2 diabetes and atherosclerosis. We have recently reported that secretory products from human adipocytes directly and acutely depressed cardiac contractile function. Objective: The purpose of this study was to identify this adipocyte-derived cardiodepressant factor. Methods and Results: Through mass spectrometry and immunoblotting, we have identified this cardiodepressant factor as FABP4. FABP4 represents 1.8% to 8.1% of total protein secreted by adipocytes in extracellular medium. FABP4 acutely depressed shortening amplitude as well as intracellular systolic peak Ca(2+) in a dose-dependent manner in isolated rat cardiomyocytes. Heart-specific FABP isoform (FABP3) revealed a similar cardiodepressant effect. The N-terminal amino acids 1 to 20 of FABP4 could be identified as the most effective cardiodepressive domain. We could exclude any effect of FABP4 on action potential duration and L-type Ca(2+) current, suggesting a reduced excitation-contraction gain caused by FABP4 as the main inhibitory mechanism. Conclusion: We conclude that the release of FABP4 from adipocytes may be involved in the development of cardiac contractile dysfunction of obese subjects. |
Keywords: | FABP4, Heart Failure, Adipocytes, Metabolic Syndrome, Animals, Rats |
Source: | Circulation Research |
ISSN: | 0009-7330 |
Publisher: | American Heart Association |
Volume: | 105 |
Number: | 4 |
Page Range: | 326-334 |
Date: | 14 August 2009 |
Official Publication: | https://doi.org/10.1161/CIRCRESAHA.109.200501 |
PubMed: | View item in PubMed |
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