Khaberni - A recent study from the University of Kentucky has shown that sleep problems in people with Alzheimer's disease may be directly associated with the accumulation of "tau" protein in the brain, even before the more obvious cognitive symptoms of the disease appear.
The accumulation of tau protein leads to brain cell damage and disrupts communication between them, typically affecting memory and cognition. However, the study also revealed that this protein can "hijack" the brain's energy supply, leaving nerve cells in a state of constant excitement and making sleep difficult.
How does this happen?
Researchers, according to the journal "npj Dementia," have used mouse models that exhibit abnormal accumulations of tau protein and found that in this case, the brain does not use glucose in the usual way to produce energy, but instead converts it into glutamate, a neurotransmitter that stimulates nerve cells and aids in learning and memory.
Although glutamate is usually beneficial, its excess makes the brain in a state of high alert, preventing it from reaching the deep, restful sleep stages necessary for cell renewal and memory formation.
Researcher Shannon McCauley from the University of Kentucky says: "It's like a fussy little child who doesn’t calm down and doesn’t sleep. The brain continuously hijacks all the glucose to make glutamate over and over, preventing deep sleep."
Early indicators
The study indicated that this dysfunction occurs in the early stages of tau protein dysfunction, before synapses fully form, which may explain why sleep problems precede Alzheimer's disease by several years.
Researchers believe that the cycle between brain hyperactivity and sleep disturbances might lead to the worsening of the disease itself, suggesting that drugs that modify brain metabolism, such as those used for epilepsy or type II diabetes, could help reduce hyperactivity and improve sleep, thereby slowing disease progression.
Scientists consider that the findings suggest that some patterns of brain hyperactivity are reversible, meaning that it is not necessary to eliminate all plaques and tangles to restore sleep.
The study also reflects the complexity of Alzheimer's disease and the necessity to address several simultaneous processes in the brain and possibly in the body itself, as the disease has previously been linked to intestinal inflammation and other factors.
