Back
Acta Physiologica 2009; Volume 197, Supplement 675
Joint meeting of The Slovenian Physiological Society, The Austrian Physiological Society and The Federation of European Physiological Societies
11/12/2009-11/15/2009
Ljubljana, Slovenia
MICE FED HIGH-FAT DIET DISPLAY ALTERED METABOLIC CHARACTERISTICS OF THEIR HEARTS AND MYOCYTES AND INCREASED VULNERABILITY TO CARDIAC INSULT
Abstract number: L78
Chase1 Anabelle, Jackson2 Christopher L., Angelini2 Gianni D., Suleiman2 Saadeh
1Department of Physiology & Pharmacology, School of Medical Sciences, University of Bristol, UK
2Bristol Heart Institute, Level 7 Bristol Royal Infirmary, University of Bristol, UK
We have recently shown that feeding apolipoprotein E knockout (apoE-/-) mice high-fat diet accelerates progression of coronary disease and induces changes to cardiac metabolism and function. These changes could be due to coronary disease and/or direct effect of high-fat feeding. This work aims to investigate whether high-fat diet induces cardiac changes in wild type mice, independent of coronary disease. Male C57/129 wild-type mice were weaned onto a normal rodent diet, and then at approximately 8 weeks old, animals were either switched onto high fat, Western-type diet (21% fat; 0.15% cholesterol) or were maintained on normal rodent diet. Animals were fed their respective diets for 6 months. Histological examination of hearts confirmed absence of coronary disease in both groups. Isolated hearts from both groups were used to measure cardiac metabolites and function. Isolated myocytes were used to measure mitochondrial flux (NAD+/NADH), contractile function and calcium transients. Mice fed high-fat diet had significantly increased levels of cardiac lactate (from 52 ± 4 to 76 ± 6 nmol/mg protein) and decreased glycogen content (from 0.09 ± 0.005 to 0.06 ± 0.008 mg/g wet weight) but had similar levels of energy rich phosphates. Evidence of metabolic stress in high-fat fed hearts was confirmed in isolated perfused myocytes which showed increased NAD+/NADH ratio (0.34 ± 0.02 vs. 0.29 ± 0.01). These metabolic differences did not alter functional characteristics of isolated perfused myocytes and hearts. However the rate of rise and decline of calcium transients were slower in high-fat fed myocytes. Intact perfused hearts from high-fat fed animals were significantly more vulnerable to reperfusion injury than those from animals fed normal diet. In conclusion, high-fat diet has profound metabolic effects on the myocardium that is independent of coronary disease. These changes appear to alter vulnerability to reperfusion injury.
To cite this abstract, please use the following information:
Acta Physiologica 2009; Volume 197, Supplement 675 :L78