Andreas Boss1, Christoph Stettler2,3, Michael Ith1,4, Stefan Jenni2,5, Chris Boesch1, Roland Kreis1
1Department of Clinical Research, University of Bern, Bern, Switzerland; 2Division of Endocrinology, Diabetes and Clinical Nutrition, Inselspital, Bern, University Hospital and University of Bern, Bern, Switzerland; 3Institute of Social and Preventive Medicine, University of Bern, Bern, Switzerland; 4Institute for Diagnostic, Interventional and Pediatric Radiology, University Hospital and University of Bern, Bern, Switzerland; 5International Center for Circulatory Health, Imperial College, London, Switzerland
Differences in the exercise-induced production of acetylcarnitine, a buffer of acetyl-CoA, in eu- vs. hyperglycaemia have been analyzed by 1H-MR spectroscopy in thigh muscle. Spectra were obtained before and after exercise (120min. at 55 to 60% VO2max, with indirect calorimetry) in 7 physically active type 1 diabetic males. During both trials, insulinaemia was kept constant and the contribution of the various substrates was determined. Acetylcarnitine was elevated 1h after exercise (p<0.0001). This increase was significantly higher in euglycaemia (p=0.0003) and coincided with higher rates of fat oxidation in this condition. Conclusion: different substrate availability alters the production of acetylcarnitine significantly.