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Muscle unloading: A comparison between spaceflight and ground-based models
Rizwan Qaisar1, Asima Karim1, Adel B Elmoselhi1,2
1Department of Basic Medical Sciences, College of Medicine, University of Sharjah, Sharjah, UAE.
Acta Physiologica (Oxford, England)
|December 17, 2019
Summary
Disuse muscle atrophy from unloading causes significant metabolic and functional changes. This review details mechanisms, contractile dysfunction, and therapeutic interventions for muscle loss.
Area of Science:
- Physiology
- Molecular Biology
- Space Medicine
Background:
- Prolonged skeletal muscle unloading (e.g., spaceflight, bed rest) induces metabolic, structural, and functional fiber changes.
- Disuse muscle atrophy is increasingly understood at cellular/molecular levels, yet gaps remain in plasticity processes.
- Effective interventions against muscle loss are hindered by incomplete knowledge of unloading-induced changes.
Purpose of the Study:
- To review current knowledge on cellular and molecular mechanisms of skeletal muscle unloading.
- To discuss advances in understanding muscle contractile dysfunction during unloading.
- To explore promising therapeutic interventions for mitigating muscle loss.
Main Methods:
- Literature review of cellular and molecular mechanisms.
- Analysis of contractile dysfunction in spaceflight and ground models.
- Evaluation of therapeutic strategies for muscle unloading.
Main Results:
- Significant progress in understanding disuse muscle atrophy mechanisms.
- Insights into contractile dysfunction during unloading.
- Identification of potential therapeutic interventions for muscle mass and strength.
Conclusions:
- Knowledge gaps persist regarding muscle plasticity during unloading.
- Further research is needed to develop effective countermeasures for muscle loss.
- Future research directions include exploring novel therapeutic targets and mechanisms.
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