Workaholics who regularly pull all-nighters aren’t just burning themselves out mentally, they could also be doing physical damage as well.
Michele Bellesi and his team from the Marche Polytechnic University in Italy have found evidence that the brain will literally start eating itself after just a few hours of sleep loss.
The team discovered this after analysing the brains of mice who either had a normal sleep pattern, or were being sleep deprived.
What they found was that the brain appears to have a ‘housekeeping’ system that during normal sleep allows it to go in, destroy worn out or damaged synapses and then recycle them, creating new membranes and proteins.
Speaking to HuffPost UK, Bellesi explains: “We believe that when a structure (let’s say a piece of synapse) is phagocyted, its destiny is probably to be degraded. Its components (membranes and proteins) are disassembled inside lysosomes and slowly recycled to build new membranes and young proteins.
“So, to this regard, phagocytosis is potentially a good thing because it prevents accumulation of old and damaged cell components that could cause malfunction.”
However after studying the mice that had been sleep deprived Bellesi and his team discovered a more worrying side-effect to this process.
“It could be also possible, at least hypothetically,” explains Bellesi “That if phagocytosis at synapses goes beyond its ‘normal’ levels, then entire synapses could be removed, thus leading to an impairment of synaptic communication.”
In essence, if the brain starts suffering from chronic sleep deprivation then these cells might not know when to stop and could start recycling healthy cells.
Bellesi and his team were able to view the process thanks to an innovative approach that used an advanced electron microscope allowing them to reconstruct the synapses and the surrounding astrocytes in 3D.
It’s important to state that at the moment, Bellesi and his team are still deciding if this process of ‘housekeeping’ is good or bad.
In addition to the astrocyte phagocytosis the team also found chronic sleep loss induced increased activation of the microglia the “guardians of the brain”.
Similar to the astrocyte phagocytosis this can initially be a good thing, however there is a flip side.
“If this activation becomes persistent (we don’t know yet if sleep loss can lead to that),” explains Bellesi “Then it might be not that good anymore because persistent microglia activation has been observed in pathological states of the brain, such as in neurodegenerative diseases, including dementia.”
“The link between chronic sleep loss and Alzheimer’s disease is intriguing, and accumulating evidence seems to suggest that the two things are related, even if we don’t know yet how. Future studies are needed to verify whether sleep loss can truly represent a risk factor for dementia.”
Their findings will appear in the latest issue of the Journal of Neuroscience.