Sleep May Help Move Harmful Molecules From The Brain

Andrew Robbertz

Author: Christopher Thomas
Published: October 17, 2013
Source: http://www.nih.gov/news/health/oct2013/ninds-17.htm

Summary:
In a study done my the National Institute of Neurological Disorders and Stroke (NINDS), Researchers made discoveries on the importance of sleep in cleaning the brain. The researchers injected a dye into the brain to see the flow of fluid through the brain.They found that during sleep, there is a 60% increase in interstitial fluid in the brain during sleep. They noticed a greater exchange of all molecules throughout the brain and a great decrease of amyloid B, which can have neurotoxic effects. This led them to the conclusion that your brain cells actually change in size between when you are awake, and when you are asleep. Previous studies have shown that some neurodegenerative diseases are caused by the accumulation of toxic molecules between brain cells. The researchers then injected another toxin into the mice brains both while asleep and while awake to see how quickly they were cleared from the brain. It disappeared faster in the brains of the mice that were asleep, further confirming that sleep continuously clears toxic chemicals from the brain.

Connection:
The study fully confirmed that sleep is directly connected to the functionality of the glymphatic system that  clears the waste in your central nervous system. This in important because the brain and spinal cord lack any lymphatic tissue. Without any lymphatic tissue, the body cannot filter any matter flowing through there. Having these neurotoxins in your brain slows your ability to control ion concentrations across cellular membranes, diminishing the speed of your nerves. Knowing that the function of the glymphatic system is linked to the shrinking of brain cells while sleeping can help scientists create new treatments for neurodegenerative diseases.

Brains Sweep Themselves Clean of Toxins During Sleep

Julia Friend
October 19, 2013

Author: Jon Hamilton
Published: October 17, 2013 4:59 PM
http://www.npr.org/blogs/health/2013/10/18/236211811/brains-sweep-themselves-clean-of-toxins-during-sleep

Summary:

Scientists have long since wondered why animals need sleep. After all, it seems like an evolutionary weak point: sleep is the perfect time to be preyed upon. But studied mice and baboons illustrate a brain sanitation process central to proper functioning of the body; this is thought to use too much energy to work during consciousness. This cleansing is by an increased rate of cerebrospinal fluid pumping through the brain, caused by the actual shrinking of brain cells during sleep. The fluid can circulate more freely with the increased space between cells, and sweeps the brain of harmful toxins such as waste proteins. This study may connect to the cause and possible solution of Alzheimer’s and other brain diseases: one of the wastes cleansed from the brain during sleep is beta amyloid, a substance related to such conditions.

Connection:

The current unit is all about cells and organelles, which relates to this article. We learned about how the cytoskeleton assists the cell’s ever-changing nature, and specifically how the microtubules offer the cell its shape. In the article’s case, the brain cells are shrinking during unconsciousness; this altering of size and therefore shape is possible because of the cytoskeleton. Just as well, proteins were a focal point in our class. Although the article only mentions them briefly, ridding the brain of waste proteins that are potentially harmful is significant to the animal’s health. Lastly, the body’s process of fighting off toxins connects to the importance of our body finding ways to safeguard itself from hydrogen peroxide. H2O2 is a naturally occurring toxin in the bodies of animals, and we have evolved with processes that counter act that harm. Similarly, the toxins mentioned in the article in the brain are innate, as is the process of clearing them during sleep through pumping cerebrospinal fluid.