Sleep loss in mice sends the brain’s immune cells into overdrive. This might be helpful in the short term, but could increase the risk of dementia in the long run
One type of glial cell, called an astrocyte, prunes unnecessary synapses in the brain to remodel its wiring. Another type, called a microglial cell, prowls the brain for damaged cells and debris.Similarly-
Bellisi’s team found that after an undisturbed sleep, astrocytes appeared to be active in around 6 per cent of the synapses in the brains of the well-rested mice. But astrocytes seemed to be more active in sleep-deprived mice – those that had lost eight hours of sleep showed astrocyte activity in around 8 per cent of their synapses, while the cells were active in 13.5 per cent of the synapses of the chronically sleep-deprived animals.
This suggests that sleep loss can trigger astrocytes to start breaking down more of the brain’s connections and their debris. “We show for the first time that portions of synapses are literally eaten by astrocytes because of sleep loss,” says Bellesi.
Century-old drug as potential new approach to autism
In a small, randomized Phase I/II clinical trial (SAT1), researchers say a 100-year-old drug called suramin, originally developed to treat African sleeping sickness, was safely administered to children with autism spectrum disorder (ASD), who subsequently displayed measurable, but transient, improvement in core symptoms of autism.
Naviaux, who is co-director of the Mitochondrial and Metabolic Disease Center at UC San Diego, believes that ASD -- and several other chronic conditions, including chronic fatigue syndrome and some autoimmune disorders -- are caused by metabolic dysfunction or impaired communication between cells in the brain, gut and immune system.
Specifically, this dysfunction is caused by abnormal persistence of the cell danger response (CDR), a natural and universal cellular reaction to injury or stress. "The purpose of CDR is to help protect the cell and jump-start the healing process," said Naviaux, by essentially causing the cell to harden its membranes, cease interaction with neighbors and withdraw within itself until the danger has passed.
"But sometimes CDR gets stuck," Naviaux said. "This prevents completion of the natural healing cycle and can permanently alter the way the cell responds to the world. When this happens, cells behave as if they are still injured or in imminent danger, even though the original cause of the injury or threat has passed."
At the molecular level, cellular homeostasis or equilibrium is altered, creating an abnormal cellular response that leads to chronic disease. "When this happens during early child development," said Naviaux, "it causes autism and many other chronic childhood disorders."
Bonus Important Information:
ENDOTOXIN INDUCES BOTH OF THESE RESPONSES!!!!!!!!!!!!!!!!!!!!!
