Headline, May 06 2022/ ''' '' THE BRAIN TAP '' ''' : DISCOVERY

''' '' THE BRAIN 


SCIENCE & TECHNOLOGY : THE GLYMPHATIC SYSTEM AND DEMENTIA. Tweaking the brain's plumbing may help delay Alzheimer's disease.

IN MOST BODILY ORGANS waste matter is cleared out by the lymphatic system. Unnecessary proteins, superfluous fluids and so on are carried away by special vessels to lymph nodes, where they are filtered out and destroyed.

The more active the organ, the more of these vessels there are. The exception is the brain, which has none. It was thus thought until recently that brain cells broke down nearby waste products in situ.

BUT a paper published in 2012 reported that the brain has a plumbing system of its own to flush out the junk.

Researchers working in the laboratory of Maiken Nedergaard, at University of Rochester, in New York state, showed that cerebrospinal fluid - the liquid which suspends the brain and acts as a cushion between it and the skull - was actively washing through the organ by hitchhiking on the pulsing of arteries and veins that happens with every heartbeat.

The fluid was collecting trash and carrying it out of the brain to lymph nodes for disposal. Now, ten years later, the discovery of this ''glymphatic'' system, so called because of the involvement of brain cells known as glia, has opened up new opportunities for the treatment of disorders.

Brainwashing : From the first studies of the glymphatic system, it was clear that it might be involved in preventing Alzheimer's disease. Alzheimer's is caused by a build-up of two types of proteins, amyloid-beta and tau.

These aggregate to form plaques and tangles that stop neurons from working properly and eventually lead to their death. When it is functioning normally, the glymphatic system clears out amyloid-beta and tau.

However, in older people, or those with Alzheimer's, this process is slower - leaving more potentially harmful proteins behind.

Giving the brain a power wash, by improving the flow of glymphatic fluid, is a potential avenue for treatment. Though the field is in its infancy, most attempts to do so have focused on an interesting quirk of the system. This is that glymphatic fluid moves through the brain only during sleeping.

The plumbing is disabled during waking hours, and is most active during the deepest sleep stages, switched on by slow-wave brain activity.

That discovery has changed how researchers think about the role of sleep, and also about the link between sleep and neurological disorders.

For many diseases, including Alzheimer's, a lack of sleep earlier in life increases the risk. Dr. Nedergaard thinks that inadequate glymphatic clearance is the reason. Even a single night of sleep deprivation can increase the amount of amyloid-beta in the brain.

Many drugs affect sleep, sometimes as a side-effect of their main purpose. A study published in BRAIN earlier this year followed almost 70,000 Danes who were being treated for high blood-pressure, using beta-blockers. Some, but not all, types of beta-blockers are able to enter the brain by passing through the blood-brain barrier.

THIS is a system of tight junctions between cells lining blood vessels in the brain, which exists to stop the admission of molecules that might upset the function of the organ.

Once there, these beta blockers affect normal patterns of sleep and wakefulness. That, in turn, promotes glymphatic circulation. Those in the study who took barrier crossing beta-blockers every day were less likely to develop Alzheimer's than people taking beta-blockers that could not enter the brain.

Another medicine, suvorexant, which is used to treat insomnia, also shows promise. In one recent study, mice with a mutation that causes early-onset Alzheimer's in people, and similar symptoms in rodents, were given this drug.

Mutated mice receiving suvorexant experienced less build up of amyloid-beta. Even more remarkably, the drug also reversed their cognitive decline. In a maze test, mutated mice on suvorexant performed as well as healthy, unmutated ones.

A preliminary human trial of this effect is now underway.

The Honour and Serving of the Latest Global Operational Research on Brain and Diseases, continues. The World Students Society thanks The Economist.

With respectful dedication to the Sufferers of Brain Disorders, and then Science, Scientists, Researchers and then Students, Professors and Teachers of the World. See Ya all prepare and register for Great  Global Elections on The World Students Society : wssciw.blogspot.com and Twitter - !E-WOW! - The Ecosystem 2011.

Good Night and God Bless

SAM Daily Times - the Voice of the Voiceless


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