Autophagy in acute brain injury.

Autophagy is an evolutionarily ancient mechanism that ensures the lysosomal degradation of old, supernumerary or ectopic cytoplasmic entities. Most eukaryotic cells, including neurons, rely on proficient autophagic responses for the maintenance of homeostasis in response to stress. Accordingly, autophagy mediates neuroprotective effects following some forms of acute brain damage, including methamphetamine intoxication, spinal cord injury and subarachnoid haemorrhage. In some other circumstances, however, the autophagic machinery precipitates a peculiar form of cell death (known as autosis) that contributes to the aetiology of other types of acute brain damage, such as neonatal asphyxia. Here, we dissect the context-specific impact of autophagy on non-infectious acute brain injury, emphasizing the possible therapeutic application of pharmacological activators and inhibitors of this catabolic process for neuroprotection.