From Earth to orbit: How to preserve muscle health in space and bed rest
Year: 2025
Type: article
Abstract: Muscle mass and strength loss during spaceflight and prolonged bed rest are inevitable consequences of disuse.Extensive evidence suggests that muscle atrophy under both conditions is primarily driven by impaired protein synthesis and reduced protein turnover.A recent review published in this Special Issue of Experimental Physiology by Bosutti et al. (2025) critically discusses the physiological mechanisms associated with microgravity-induced loss of muscle mass and function, as well as the latest countermeasures aimed at mitigating its effects (Figure 1 in Bosutti et al., 2025).At the molecular level, dysregulation of the Akt/mechanistic target of rapamycin signaling pathway, which governs protein synthesis, along with activation of multiple proteolytic pathways, such as the ubiquitin-proteasome system and autophagy, play a central role in muscle wasting.Additionally, disruptions in cytoskeletal integrity and extracellular matrix organization lead to spatial disarray of cellular organelles, resulting in mitochondrial and nuclear dysfunction.Such structural changes may also compromise neuromuscular junctions, potentially explaining the disproportionate decline in muscle strength relative to muscle mass, as observed in bed rest studies (Table 2 in Bosutti et al., 2025).Beyond structural impairments, both spaceflight and prolonged bed rest induce significant metabolic disturbances, including substrate inflexibility, mitophagy, lipotoxicity, mito-nuclear communication deficits and insulin resistance, all of which highlight the urgent need for effective countermeasures against muscle wasting -both on Earth and in orbit.
Source: Experimental Physiology
DOI: 10.1113/ep092729
Authors: Antonios Matsakas, Colleen Deane
Language: English
Subfield: Physiology
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $2,940
OpenAlex ID: W4408868400