How brain cells recycle themselves

Neurons, marked in red and green, constantly recycle toxic protein aggregates, colored in light blue, by autophagy © Vassiliki Nikoletopoulou Lab A study published on June 5, 2023 in Neuron by a team from the University of Lausanne lifts part of the veil on the autophagy mechanism in neurons and glial cells . Autophagy is an essential process in cellular life: it cleans up the waste produced by the cell's machinery, eliminating useless, defective or toxic components, and recycling those that can be. This small internal reprocessing plant then provides the cell with a raw material that can be used to renew its constituents, such as proteins and organelles. But when this mechanism goes wrong, when autophagy malfunctions, problems arise. Within brain cells, in neurons and glia, mutations in autophagy genes are linked to certain serious neurodevelopmental disorders, such as autism or epilepsy, or predispose to the development of neurodegenerative diseases later in life, such as Alzheimer's or Parkinson's. How autophagy works - First of all, the waste products are enclosed in a kind of small sac, called an autophagic vesicle or autophagosome, which then merges with the lysosome, another enzyme-filled sac: this is where the various residues - proteins, sugars, lipids, genetic material - are degraded into their primary constituents, building blocks that are then reused by the cell. But when autophagy is impaired, neurons and other brain cells accumulate damaged proteins and organelles that clutter up their space and function.