Sleep Deprivation May Cause Brain To Eat Itself: Study
Several scientific researches provide evidence that sleep deprivation is bad for our health, and the National Sleep Foundation has even updated its recommended hours of sleep as a guide to keep everyone in check.
Trying to catch up on sleep only becomes more difficult as we age, but new research shows that allowing our bodies to suffer from sleep deprivation ultimately damages our brains since it triggers an overdrive in cell activity, causing self-cannibalism.
Dangerous Effect Of Sleep Deprivation
Researchers from the Marche Polytechnic University in Italy wanted to find out how chronic sleep deprivation affects the brain's microglial activity since previous researches showed evidence that lack of sleep puts people at risk of neurological disorders.
To do this, they purposefully deprived sleep in some mice to monitor brain activity during a chronically sleep-deprived state. The test subjects consisted of well-rested mice, mice that were kept awake eight hours longer than usual, and mice that were kept awake for five days to mimic the effects of chronic sleep deprivation.
The researchers found strong evidence that astrocytes, the very cells whose job is to search and destroy old synapses and exhausted brain cells on a daily basis, go into overdrive when a mouse is sleep-deprived. Astrocytes usually just prune synapses that require rewiring and eat up old cells to replace them with healthy ones, but the researchers discovered that they are more active in the brains of sleep-deprived mice — too active, in fact.
"We show for the first time that portions of synapses are literally eaten by astrocytes because of sleep loss," researcher Michele Bellesi said.
Autocannibalism In The Brain
Upon further observation, the researchers noted that astrocytes seem to prune and destroy even healthy synapses and cells when the brain is not well-rested.
According to the research, astrocyte activity in well-rested mice was only at 6 percent, but it rose up to 8 percent in mice that lacked sleep. On the other hand, microglial activity in mice that mimicked chronic sleep deprivation experienced a 13.5 percent spike in astrocyte activity.
"[Chronic] sleep restriction but not acute sleep loss activates microglia ... in the absence of overt signs of neuroinflammation, suggesting that like many other stressors, extended sleep disruption may lead to a state of sustained microglia activation, perhaps increasing the brain's susceptibility to other forms of damage," the research concludes.
Bellesi notes that his team's findings are worrying because increased microglial activity has been linked to many brain disorders, including Alzheimer's disease. However, the team is not stopping with their research, and their next plan is to investigate the just how long increased microglial activity lasts in sleep-deprived subjects.