Aspects of cardiomyopathy are exacerbated by elevated dietary fat in copper-restricted rats.
The objective of this study was to determine if a high fat diet having a 2:1 saturated-polyunsaturated fatty acid ratio exacerbates signs of copper deficiency. Male weanling Long-Evans rats were randomly placed into one of the following treatment groups: adequate copper low fat or deficient copper high fat. The levels of fat used were 31 or 12% of daily energy, and copper concentrations were 94.5 micromol/kg and <15.8 micromol/kg in the copper-adequate and copper-deficient diets, respectively. Cardiac hypertrophy as well as lower liver copper levels and superoxide dismutase activity were observed in both groups of copper-deficient rats. Irrespective of copper level, consumption of the high fat diet resulted in the thickening of the interventricular septum and left ventricular free wall. Electrocardiograms revealed that the copper-deficient high fat diet led to a significantly smaller QT interval compared with all other groups. Significantly greater S-wave voltage due to copper deficiency was observed. Significantly lower heart cytochrome c oxidase (CCO) activity was found in the copper-deficient groups with the copper deficient high fat group showing the lowest activity. Western blots of the cardiac non-myofibrillar fraction demonstrated lower amounts of CCO nuclear encoded peptides in the copper-deficient groups, with the least amount seen in the copper-deficient high fat treatment. These data suggest that a high level of dietary fat exacerbates some of the signs of copper deficiency.
Jalili
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T
Department of Human Nutrition and Food Management, Ohio State University, Columbus 43210, USA.
Medeiros
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DM
Wildman
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RE
D000818:Animals; D015153:Blotting, Western; D009202:Cardiomyopathies / Q000209:etiology* / Q000503:physiopathology; D002784:Cholesterol / Q000097:blood; D003300:Copper / Q000008:administration & dosage* / Q000172:deficiency*; D004032:Diet; D004041:Dietary Fats / Q000008:administration & dosage*; D004562:Electrocardiography; D003576:Electron Transport Complex IV / Q000032:analysis / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D002149:Energy Intake; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D009206:Myocardium / Q000201:enzymology; D051381:Rats; D013482:Superoxide Dismutase / Q000378:metabolism
D004041:Dietary Fats; D003300:Copper; D002784:Cholesterol; D007770:L-Lactate Dehydrogenase; D013482:Superoxide Dismutase; D003576:Electron Transport Complex IV