Int J Sports Med 2023; 44(11): 763-777
DOI: 10.1055/a-2044-8277

Protein Turnover in Skeletal Muscle: Looking at Molecular Regulation towards an Active Lifestyle

Rita Pinho Ferreira
1   LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, Aveiro, Portugal
Jose Alberto Duarte
2   TOXRUN – Toxicology Research Unit, University Institute of Health Sciences, CESPU, CRL, Gandra, Portugal
3   CIAFEL, Faculty of Sports, University of Porto and Laboratory for Integrative and Translational Research in Population Health (ITR), Porto, Portugal
› Author Affiliations
Funding This work was supported by LAQV (UIDB/50006/2020), CIAFEL (UID/DTP/00617/2020) and ITR (LA/P/0064/2020) through national founds by the Portuguese Foundation for Science and Technology (FCT) and co-financed by the European Regional Development Fund (FEDER), within the PT2020 Partnership Agreement.


Skeletal muscle is a highly plastic tissue, able to change its mass and functional properties in response to several stimuli. Skeletal muscle mass is influenced by the balance between protein synthesis and breakdown, which is regulated by several signaling pathways. The relative contribution of Akt/mTOR signaling, ubiquitin-proteasome pathway, autophagy among other signaling pathways to protein turnover and, therefore, to skeletal muscle mass, differs depending on the wasting or loading condition and muscle type. By modulating mitochondria biogenesis, PGC-1α has a major role in the cell’s bioenergetic status and, thus, on protein turnover. In fact, rates of protein turnover regulate differently the levels of distinct protein classes in response to atrophic or hypertrophic stimuli. Mitochondrial protein turnover rates may be enhanced in wasting conditions, whereas the increased turnover of myofibrillar proteins triggers muscle mass gain. The present review aims to update the knowledge on the molecular pathways implicated in the regulation of protein turnover in skeletal muscle, focusing on how distinct muscle proteins may be modulated by lifestyle interventions with emphasis on exercise training. The comprehensive analysis of the anabolic effects of exercise programs will pave the way to the tailored management of muscle wasting conditions.

Publication History

Received: 04 November 2022

Accepted: 28 February 2023

Accepted Manuscript online:
28 February 2023

Article published online:
17 July 2023

© 2023. Thieme. All rights reserved.

Georg Thieme Verlag
Rüdigerstraße 14, 70469 Stuttgart, Germany

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