Sleep is a potentially very dangerous activity. When we are sleeping, we are very vulnerable to enemies, such as predators during our early evolution, but increasingly we are worried about human enemies who can take advantage of our helpless state. Why, then, do we do it?
According to new research published in the journal Science, this is the only time that our brain can get rid of toxic waste that its cells produce.
A Newly-Discovered Waste Disposal System
Last year, researchers reported the first evidence that the brain had a waste disposal system. This system, dubbed the glymphatic system (short for glial lymphatic system, after a type of brain cell involved in the system, and the lymphatic system), allows the brain to remove toxic byproducts of metabolic processes that previously were thought to be only accumulated or disposed of in individual cells. Although the lymphatic system cleans these products from the rest of the body, there is no lymphatic circulation in the brain.
Instead, when we are sleeping, tiny channels in the brain expand and become filled with cerebrospinal fluid that is saturated with waste. These channels carry the waste out of the brain into the spine and then transfer it to the lymphatic system.
The discovery of this system depended on the ability to perform imaging of the brain in living mice, both awake and asleep. Getting the mice to fall asleep in the imaging machine was in itself a task, and it took more than two years just to accomplish this prefatory step.
Why Do We Need to Sleep to Remove Waste?
The lymphatic system is continuously removing waste from our body. Why can’t the glymphatic system do the same? The reason is the energy required to move fluid across the cell membranes in the brain. The brain is not capable of both removing waste and functioning at the same time.
A Key to Alzheimer’s Disease?
One potential ramification of this discovery is that it may give us greater insight into preventing and treating Alzheimer’s disease,which is partly characterized by an accumulation of certain waste in the brain. It’s possible that problems with sleep or with the function of the glymphatic system during sleep contribute to the development of Alzheimer’s.
It’s also possible that this explains some of the short-term cognitive problems that people experience due to sleep apnea. When people are missing out on sleep, they will experience short-term increased accumulation of toxins in the brain that may impair the function of brain cells.
Fortunately, sleep apnea is treatable. If you are suffering from the effects of sleep apnea, we can help with comfortable, convenient sleep apnea treatment. Please contact the Advanced Dental Sleep Treatment Center in Omaha today for more information.