Removal of damaged mitochondria in muscle and how it changes with aging, exercise, and inactivity

The maintenance of a healthy mitochondrial pool is crucial for preserving skeletal muscle quality.

• Skeletal muscle health is linked to mitochondrial turnover, which involves a balance between synthesis and degradation of organelles.
• Mitophagy is the process of selectively removing dysfunctional mitochondria to maintain mitochondrial quality control.
• Current understanding of the initial stages of mitophagy is well established, but the terminal step involving degradation via lysosomes is not yet fully understood.
• Proteolytic functions are essential for the breakdown of dysfunctional mitochondria and are important for understanding mitophagy mechanisms.
• Physiological conditions such as ageing, exercise, and disuse can affect mitophagy and lysosomal adaptations in skeletal muscle.

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