Sleep Deprivation Could Make the Brain Eat Itself, Increasing Risk of Alzheimer's
A new study from the Marche Polytechnic University in Italy revealed that chronic sleep deprivation could make the brain eat itself, increasing the risk of Alzheimer's and other neurological disorders.
The study, published in The Journal of Neurosciences, showed that lack of sleep may cause certain type of cells called astrocytes, which is responsible for cleaning out worn-out cells and debris, to go into overdrive, making them clean out more of the brain's connection and debris.
"In the short term, this might be beneficial -- clearing potentially harmful debris and rebuilding worn circuitry might protect healthy brain connections," said lead author Michele Bellesi of the Marche Polytechnic University, in a report from New Scientist. "But it may cause harm in the long term, and could explain why a chronic lack of sleep puts people at risk of Alzheimer's disease and other neurological disorders."
For the study, the researchers conducted an experiment involving two groups of mice. The first group was allowed to sleep for as long as they want or was kept awake for eight hours. On the other hand, the mice in the second group were kept awake for five straight days to mimic the effects of chronic sleep loss. The team then compared the brains of the two groups, looking specifically at astrocytes.
The researchers found that the astrocytes in the in the brain of the sleep deprived mice were more active than those in the well-rested group. The astrocytes in the first group appear to be active in around 6 percent of the synapses while, the astrocytes in mice that lost 8 hours of sleep were3 active in around 8 percent of the synapses. On the other hand, mice that were kept awake for five days have astrocyte activity in around 13.5 percent of their synapses.
With these results, the researchers have presented that sleep deprivation could make astrocytes to literally eat portions of the brain's synapses. Because more of the brain's connection and debris were broken down by astrocytes during sleep deprivation, the risk of Alzheimer's and other neurological disorders significantly increases.