Endocrine, Metabolic, and Skeletal Muscle Proteomic Responses During Energy Deficit With Concomitant Aerobic Exercise...

Area of Science:

• Human physiology
• Skeletal muscle biology
• Metabolic adaptation

Background:

• Energy deficit is an evolutionary stressor impacting lifespan and healthspan.
• Skeletal muscle's role in locomotion and metabolic health is crucial, yet its molecular response to energy deficit is understudied.

Purpose of the Study:

• To investigate the molecular effects of a short-term energy deficit with exercise on human skeletal muscle phenotype.
• To understand adaptations in protein abundance and synthesis rates within skeletal muscle during energy deficit.

Main Methods:

• Utilized stable isotope (D2O) labeling and peptide mass spectrometry.
• Analyzed protein abundance and synthesis rates in skeletal muscle of healthy men after a 5-day energy deficit (78% reduction) with aerobic exercise.

Main Results:

• Observed a shift towards a more oxidative skeletal muscle phenotype.
• Identified increased abundance and synthesis of mitochondrial proteins involved in fat oxidation and proteostasis.
• Noted a reduction in extracellular matrix proteins, potentially mitigating age-related fibrosis.

Conclusions:

• Energy deficit combined with exercise positively modulates skeletal muscle metabolism.
• Muscle metabolic pathways are preserved and enhanced, showing increased oxidative capacity and improved mitochondrial function.
• Skeletal muscle adapts to energy deficit with exercise, promoting a healthier metabolic profile and potentially counteracting muscle aging.