Maximal-intensity exercise does not fully restore muscle pyruvate dehydrogenase complex activation after 3 days of high-fat dietary intake

Constantin-Teodosiu, D.; Cederblad, Gitten; Bergstrom, Mats; Greenhaff, P. L.

Abstract

Background & aims: Exercise activates muscle pyruvate dehydrogenase complex (PDC), but moderate intensity exercise fails to fully activate muscle PDC after high-fat diet [1]. We investigated whether maximal intensity exercise overcomes this inhibition.
Methods: Quadriceps femoris muscle biopsy samples were obtained from healthy males at rest, and after 46 and 92 electrically-evoked maximal intermittent isometric contractions, which were preceded by 3 days of either low- (18%) or high- (69%) isocaloric dietary fat intake (LFD and HFD, respectively).
Results: The ratio of PDCa (active form) to total PDCt (fully activated) at rest was 50% less after HFD (0.32 ± 0.01 vs 0.15 ± 0.01; P<0.05). This ratio increased to 0.77 ± 0.06 after 46 contractions (P<0.001) and to 0.98 ± 0.07 after 92 contractions (P<0.001) in LFD. The corresponding values after HFD were less (0.54 ± 0.06; P<0.01 and 0.70 ± 0.07; P<0.01, respectively). Resting muscle acetyl-CoA and acetylcarnitine content was greater after HFD than LFD (both P<0.05), but their rate of accumulation in the former was reduced during contraction. Muscle lactate content after 92 contractions was 30% greater after HFD (P<0.05). Muscle force generation during contraction was no different between interventions, but HFD lengthened muscle relaxation time (P<0.05). Daily urinary total carnitine excretion after HFD was 2.5-fold greater than after LFD (P<0.01).
Conclusions: A bout of maximal intense exercise did not overcome dietary fat-mediated inhibition of muscle pyruvate dehydrogenase complex activation, and was associated with greater muscle lactate accumulation, as a result of lower PDC flux, and increased muscle relaxation time.

Citation

Constantin-Teodosiu, D., Cederblad, G., Bergstrom, M., & Greenhaff, P. L. (2019). Maximal-intensity exercise does not fully restore muscle pyruvate dehydrogenase complex activation after 3 days of high-fat dietary intake. Clinical Nutrition, 38(2), 948-953. https://doi.org/10.1016/j.clnu.2018.02.001

• Journal Article Type: Article
• Acceptance Date: Feb 2, 2018
• Online Publication Date: Feb 15, 2018
• Publication Date: Apr 1, 2019
• Deposit Date: Mar 23, 2018
• Publicly Available Date: Feb 16, 2019
• Journal: Clinical Nutrition
• Print ISSN: 0261-5614
• Electronic ISSN: 1532-1983
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 38
• Issue: 2
• Pages: 948-953
• DOI: https://doi.org/10.1016/j.clnu.2018.02.001
• Keywords: Nutrition and Dietetics; Critical Care and Intensive Care Medicine
• Public URL: https://nottingham-repository.worktribe.com/output/911802
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S0261561418300645
• Additional Information: This article is maintained by: Elsevier; Article Title: Maximal-intensity exercise does not fully restore muscle pyruvate dehydrogenase complex activation after 3 days of high-fat dietary intake; Journal Title: Clinical Nutrition; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.clnu.2018.02.001; Content Type: article; Copyright: © 2019 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
• Contract Date: Mar 23, 2018