Helmholtz Gemeinschaft


Is metabolic flexibility altered in multiple sclerosis patients?

[img] PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader

Item Type:Article
Title:Is metabolic flexibility altered in multiple sclerosis patients?
Creators Name:Mähler, A. and Steiniger, J. and Bock, M. and Brandt, A.U. and Haas, V. and Boschmann, M. and Paul, F.
Abstract:OBJECTIVES: Metabolic flexibility is defined as ability to adjust fuel oxidation to fuel availability. Multiple sclerosis (MS) results in reduced muscle strength and exercise intolerance. We tested the hypothesis that altered metabolic flexibility contributes to exercise intolerance in MS patients. METHODS: We studied 16 patients (all on glatiramer) and 16 matched healthy controls. Energy expenditure (EE), and carbohydrate (COX) and lipid oxidation (LOX) rates were determined by calorimetry, before and after an oral glucose load. We made measurements either at rest (canopy device) or during 40 min low-grade (0.5 W/kg) exercise (metabolic chamber). We also obtained plasma, and adipose tissue and skeletal muscle dialysate samples by microdialysis to study tissue-level metabolism under resting conditions. RESULTS: At rest, fasting and postprandial plasma glucose, insulin, and free fatty acid levels did not differ between patients and controls. Fasting and postprandial COX was higher and LOX lower in patients. In adipose, fasting and postprandial dialysate glucose, lactate, and glycerol levels were higher in patients vs. controls. In muscle, fasting and postprandial dialysate metabolite levels did not differ significantly between the groups. During exercise, EE did not differ between the groups. However, COX increased sharply over 20 min in patients, without reaching a steady state, followed by an immediate decrease within the next 20 min and fell even below basal levels after exercise in patients, compared to controls. CONCLUSIONS: Glucose tolerance is not impaired in MS patients. At rest, there is no indication for metabolic inflexibility or mitochondrial dysfunction in skeletal muscle. The increased adipose tissue lipolytic activity might result from glatiramer treatment. Autonomic dysfunction might cause dysregulation of postprandial thermogenesis at rest and lipid mobilization during exercise.
Keywords:Carbohydrate Metabolism, Case-Control Studies, Dietary Carbohydrates, Energy Metabolism, Fasting, Glucose Clamp Technique, High-Fat Diet, Hyperinsulinism, Lipid Metabolism, Multiple Sclerosis, Oxidation-Reduction
Source:PLoS ONE
Publisher:Public Library of Science
Page Range:e43675
Date:28 August 2012
Official Publication:https://doi.org/10.1371/journal.pone.0043675
PubMed:View item in PubMed

Repository Staff Only: item control page


Downloads per month over past year

Open Access
MDC Library