Improved cardiac function and dietary fatty acid metabolism after modest weight loss in subjects with impaired glucose tolerance

• Published in: American journal of physiology: endocrinology and metabolism Vol. 306; no. 12; pp. E1388 - E1396
• Main Authors: Labbé, Sébastien M., Noll, Christophe, Grenier-Larouche, Thomas, Kunach, Margaret, Bouffard, Lucie, Phoenix, Serge, Guérin, Brigitte, Baillargeon, Jean-Patrice, Langlois, Marie-France, Turcotte, Eric E., Carpentier, André C.
• Format: Journal Article
• Language: English
• Published: United States American Physiological Society 15.06.2014
• Subjects: Acetic Acid; Body Mass Index; Carbon Radioisotopes; Combined Modality Therapy; Diet, Reducing; Dietary Fats - metabolism; Fatty Acids; Female; Fluorine Radioisotopes; Glucose; Glucose Intolerance - etiology; Glucose Intolerance - prevention & control; Heart Ventricles - diagnostic imaging; Heart Ventricles - metabolism; Heart Ventricles - physiopathology; Humans; Insulin; Intervention; Life Style; Male; Middle Aged; Motor Activity; Obesity - diet therapy; Obesity - metabolism; Obesity - physiopathology; Obesity - therapy; Positron-Emission Tomography; Postprandial Period; Radionuclide Ventriculography; Radiopharmaceuticals; Tomography; Ventricular Dysfunction, Left - diagnostic imaging; Ventricular Dysfunction, Left - etiology; Ventricular Dysfunction, Left - prevention & control; Weight Loss; fatty acids; positron emission tomography; food metabolism
• ISSN: 0193-1849; 1522-1555; 1522-1555
• DOI: 10.1152/ajpendo.00638.2013

Using a novel positron emission tomography (PET) method with oral administration of 14( R, S)-[ 18 F]-fluoro-6-thia-heptadecanoic acid ( 18 FTHA), we recently demonstrated that subjects with impaired glucose tolerance (IGT) display an impairment in cardiac function associated with increased myocardial uptake of dietary fatty acids. Here, we determined whether modest weight loss induced by lifestyle changes might improve these cardiac metabolic and functional abnormalities. Nine participants with IGT, enrolled in a one-year lifestyle intervention trial, were invited to undergo determination of organ-specific postprandial dietary fatty acids partition using the oral 18 FTHA method, and cardiac function and oxidative metabolic index using PET [ 11 C]acetate kinetics with ECG-gated PET ventriculography before and after the intervention. The intervention resulted in significant weight loss and reduction of waist circumference, with reduced postprandial plasma glucose, insulin, and triglycerides excursion. We observed a significant increase in stroke volume, cardiac output, and left ventricular ejection fraction associated with reduced myocardial oxidative metabolic index and fractional dietary fatty acid uptake. Modest weight loss corrects the exaggerated myocardial channeling of dietary fatty acids and improves myocardial energy substrate metabolism and function in IGT subjects.