Copyright © 2006, European Society of Cardiology
Fatty acid transporter levels and palmitate oxidation rate correlate with ejection fraction in the infarcted rat heart
aCardiac Metabolism Research Group, Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
bDepartment of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
cNuffield Department of Anaesthetics, University of Oxford, Radcliffe Infirmary, Oxford, UK
* Corresponding author. Tel.: +44 1865 282248; fax: +44 1865 282272. Email address: Kieran.Clarke{at}physiol.ox.ac.uk
Objectives: Cardiac fatty acid uptake occurs predominantly via sarcolemmal transporter proteins; fatty acid translocase (FAT/CD36), plasma membrane fatty acid binding protein (FABPpm) and fatty acid transporter proteins (FATP) 1 and 6. We hypothesised that levels of the fatty acid transporters would be reduced in the chronically infarcted rat heart, in parallel with reduced dependence on fatty acid utilisation.
Methods and results: In vivo left ventricular ejection fractions, measured using echocardiography, were 36% lower in rats six months after coronary artery ligation than in sham-operated control rats. In isolated, perfused, infarcted hearts, 3H-palmitate oxidation was 30% lower, and correlated with in vivo ejection fractions. As myocardial lipid incorporation was also reduced by 25%, total palmitate utilisation was 29% lower in the infarcted rat heart. The protein levels of the cardiac fatty acid transporters were reduced in the infarcted rat heart; FAT/CD36 by 36%, FABPpm by 12%, FATP6 by 21% and FATP1 by 26%, and the cytosolic fatty acid binding protein (cFABP) was 47% lower than in sham-operated rat hearts. Fatty acid transporter levels correlated with both palmitate oxidation rates and cardiac ejection fractions.
Conclusions: Reductions in fatty acid oxidation and lipid incorporation rates were accompanied by downregulation of the cardiac fatty acid transporters. The metabolic shift away from fatty acid utilisation was proportional to the degree of functional impairment in the chronically infarcted rat heart.
KEYWORDS Heart failure; Infarction; Lipid metabolism; Energy metabolism
Abbreviations: FFA, free fatty acid • FAT/CD36, fatty acid translocase • FABPpm, plasma membrane fatty acid binding protein • FATP1 and 6, fatty acid transporter proteins • cFABP, cytosolic fatty acid binding protein • MCAD, medium chain acyl-coenzyme A dehydrogenase.
Time for primary review 28 days
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  R. W. Schwenk, J. J.F.P. Luiken, A. Bonen, and J. F.C. Glatz Regulation of sarcolemmal glucose and fatty acid transporters in cardiac disease Cardiovasc Res, July 15, 2008; 79(2): 249 - 258. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. D. Evans and Y. Niu Hypolipidaemic effects of high-dose insulin therapy Br. J. Anaesth., April 1, 2008; 100(4): 429 - 433. [Full Text] [PDF]
|
|