Changes in cardiac energy metabolic pathways in overweighed rats fed a high-fat diet.
BACKGROUND
Heart produces ATP through long-chain fatty acids beta oxidation.


OBJECTIVE
To analyze whether in ventricular myocardium, high-fat diet may modify the expression of proteins associated with energy metabolism before myocardial function was affected.


METHODS
Wistar Kyoto rats were divided into two groups: (a) rats fed standard diet (control; n = 6) and (b) rats fed high-fat diet (HFD; n = 6). Proteins from left ventricles were analyzed by two-dimensional electrophoresis, mass spectrometry and Western blotting.


RESULTS
Rats fed with HFD showed higher body weight, insulin, glucose, leptin and total cholesterol plasma levels as compared with those fed with standard diet. However, myocardial functional parameters were not different between them. The protein expression of 3-ketoacyl-CoA thiolase, acyl-CoA hydrolase mitochondrial precursor and enoyl-CoA hydratase, three long-chain fatty acid β-oxidation-related enzymes, and carnitine-O-palmitoyltransferase I was significantly higher in left ventricles from HFD rats. Protein expression of triosephosphate isomerase was higher in left ventricles from HFD rats than in those from control. Two α/β-enolase isotypes and glyceraldehyde-3-phosphate isomerase were significantly increased in HFD rats as compared with control. Pyruvate and lactate contents were similar in HFD and control groups. Expression of proteins associated with Krebs cycle and mitochondrial oxidative phosphorylation was higher in HFD rats.


CONCLUSIONS
Expression of proteins involved in left ventricle metabolic energy was enhanced before myocardial functionality was affected in rats fed with HFD. These findings may probably indicate higher cardiac energy requirement due to weight increase by HFD.
Cardiovascular Institute, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain.
Javier
J
Modrego
Natalia
N
de las Heras
Jose J
JJ
Zamorano-León
Petra J
PJ
Mateos-Cáceres
Beatriz
B
Martín-Fernández
Maria
M
Valero-Muñoz
Vicente
V
Lahera
Antonio J
AJ
López-Farré
D000102:Acetyl-CoA C-Acyltransferase / Q000235:genetics / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D001835:Body Weight; D002334:Carnitine O-Palmitoyltransferase / Q000235:genetics / Q000378:metabolism; D002784:Cholesterol / Q000097:blood; D059305:Diet, High-Fat; D004734:Energy Metabolism; D004746:Enoyl-CoA Hydratase / Q000235:genetics / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D005986:Glyceraldehyde 3-Phosphate / Q000235:genetics / Q000378:metabolism; D007091:Image Processing, Computer-Assisted; D007328:Insulin / Q000097:blood; D019344:Lactic Acid / Q000032:analysis; D020738:Leptin / Q000097:blood; D008297:Male; D053858:Metabolic Networks and Pathways / Q000502:physiology*; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism*; D050177:Overweight / Q000378:metabolism*; D010085:Oxidative Phosphorylation; D010170:Palmitoyl-CoA Hydrolase / Q000235:genetics / Q000378:metabolism; D010751:Phosphopyruvate Hydratase / Q000235:genetics / Q000378:metabolism; D019289:Pyruvic Acid / Q000032:analysis; D051381:Rats; D011921:Rats, Inbred WKY; D014280:Triglycerides / Q000097:blood; D014305:Triose-Phosphate Isomerase / Q000235:genetics / Q000378:metabolism
D005227:Fatty Acids; D007328:Insulin; D020738:Leptin; D024101:Mitochondrial Proteins; D014280:Triglycerides; D005986:Glyceraldehyde 3-Phosphate; D019344:Lactic Acid; D019289:Pyruvic Acid; D002784:Cholesterol; D000102:Acetyl-CoA C-Acyltransferase; D002334:Carnitine O-Palmitoyltransferase; D010170:Palmitoyl-CoA Hydrolase; D010751:Phosphopyruvate Hydratase; D004746:Enoyl-CoA Hydratase; D014305:Triose-Phosphate Isomerase