When lysosomal function is impaired, cells release dysfunctional mitochondria through large extracellular vesicles instead of breaking them down. This process occurs independently of autophagy, helps preserve cellular health, and is observed in aged or diseased heart tissues, offering insights into ageing and cardiac disease.
August 2023 – Nature Communications
Key Takeaways
- Cells expel damaged mitochondria through extracellular vesicles when lysosomes can’t break them down, preserving cellular function: When lysosomes, which normally break down and recycle cellular waste, fail to function properly, cells expel dysfunctional mitochondria through extracellular vesicles (EVs). This mechanism prevents the accumulation of damaged components inside the cell, helping to maintain overall cellular health and prevent potential damage that could accelerate ageing
- This process is independent of autophagy, a key cellular recycling mechanism: Autophagy is a well-known process where cells degrade and recycle their own components, including mitochondria. However, this newly identified mechanism of mitochondrial disposal via extracellular vesicles operates separately from autophagy. It suggests that cells have alternative pathways to manage mitochondrial quality, especially when traditional recycling methods are impaired
- Impaired mitochondrial clearance is more prevalent in aged or diseased heart tissue: As tissues age or experience disease, their ability to efficiently clear out dysfunctional mitochondria declines. This impaired clearance is particularly noted in heart tissue, which is highly dependent on healthy mitochondria for energy. The accumulation of damaged mitochondria in these tissues contributes to cellular decline and tissue dysfunction, common features of ageing
Efficient disposal of damaged mitochondria is crucial for maintaining cellular function, especially in energy-demanding organs like the heart. By removing dysfunctional components, cells can maintain better health and potentially slow down the degenerative processes associated with ageing. This mechanism could offer new therapeutic insights for promoting longevity and preventing age-related diseases, particularly those involving cardiac health.
Read the article at: Fang, Feifei, et al. “Mitochondria are secreted in extracellular vesicles when lysosomal function is impaired.” Nature Communications, vol. 14, no. 1, 2023, article 5267.