Mitophagy

Definition

Mitophagy is the selective removal of damaged, dysfunctional, or unnecessary mitochondria through the autophagy-lysosome system. It is a mitochondrial quality-control process that helps cells identify mitochondria that are no longer working properly, isolate them, and break them down so their components can be recycled. [1] [2] [3]

Why It Matters in Ageing Research

Mitophagy matters because mitochondria are central to energy production, cellular stress responses, inflammation, and cell survival. With ageing, mitochondrial damage can accumulate and quality-control systems may become less effective, contributing to mitochondrial dysfunction, altered metabolism, and tissue decline. Mitophagy is therefore studied as one way cells maintain mitochondrial health and as a possible target for interventions that aim to preserve function during ageing. [3] [4] [5]

Common Confusion

• Mitophagy is a type of autophagy, but it specifically targets mitochondria.
• More mitophagy is not always better; cells need balanced mitochondrial removal and replacement.
• Mitophagy is not the same as mitochondrial biogenesis, which creates new mitochondria.

Related Reading

• Autophagy
• Mitochondrial Dysfunction
• Proteostasis

References

1. Lemasters, J. J. (2005). Selective mitochondrial autophagy, or mitophagy, as a targeted defense against oxidative stress, mitochondrial dysfunction, and aging. https://pubmed.ncbi.nlm.nih.gov/15811512/
2. Youle, R. J., & Narendra, D. P. (2011). Mechanisms of mitophagy. https://pubmed.ncbi.nlm.nih.gov/21779032/
3. Pickles, S., Vigié, P., & Youle, R. J. (2018). Mitophagy and quality control mechanisms in mitochondrial maintenance. https://pubmed.ncbi.nlm.nih.gov/29358636/
4. Sun, N., Youle, R. J., & Finkel, T. (2016). The mitochondrial basis of aging. https://pubmed.ncbi.nlm.nih.gov/27108561/
5. Palikaras, K., Lionaki, E., & Tavernarakis, N. (2018). Mechanisms of mitophagy in cellular homeostasis, physiology and pathology. https://pubmed.ncbi.nlm.nih.gov/29620996/