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.