In our cells, it is like our planet: resources are consumed and waste is produced. In one case, as in the other, sobriety is required, inasmuch as all that can be must be reused! At the cellular level, this good waste management goes through a process called “ autophagy And just like on a planetary level, when things go wrong, so is chaos…
The term “autophagy” may come from the Greek “one eats oneself,” if you thought you were discovering a vile story of cannibalism here, you will be a bit disappointed. In fact, this biological mechanism is on the contrary all that is cleaner and more virtuous: it allows our cells to get rid of their useless, defective or toxic components, and to recycle the ones that could be.
Most of the time, cells use autophagy to do the chores: waste that messes up the cell is collected in a kind of small sac — autophagosomes — which then fuse with a vesicle called a lysosome. The latter is full of enzymes that are able to chop everything into small pieces. The advantage is that spare parts produced this way—of proteins, sugars, lipids, or genetic material—can be used to make new, fully functional components. As a result, autophagy is especially beneficial when times are tough and the cell lacks external input Nutrients (eg in a fasted state): This mechanism would allow it to survive by recycling its components, worn out or unnecessary, to produce what is absolutely necessary to it while waiting for better days.
Recycling of cellular waste through autophagy
- In the cell, waste to be disposed of is collected in “bags” called autophagosomes (represented here as a garbage bag).
- Autophagosomes fuse with lysosomes (represented by a bottle of detergent).
- Enzymes in lysosomes degrade cellular waste and the resulting particle fragments are released into the cell (the step represented by a cart full of aggregates).
- This material can then be used to produce new components for the cell (the step represented by the plant, from which a pallet of new goods emerges).
But in some people, autophagy is disrupted or disrupted. All in all, this process becomes less effective as we age. In these cases, the occurrence of several diseases – neurodegenerative, infectious, cancerous, cardiovascular, metabolic … – seems to be favored. Decreased autophagic efficiency can, for example, contribute to the accumulation of harmful protein aggregates, an anomaly typical of many neurodegenerative diseases such as Alzheimer’s or Parkinson’s. This is the reason behind many teams of researchers, particularly under search software inserm AgeMed and InterAging are for agingwe’re working out how to target this process to keep our cells in good shape for longer.
To learn more about autophagy, its role in the normal and pathological functioning of our body, as well as the studied ways to stimulate this process (or, conversely, to inhibit it) in order to combat specific diseases: