Scientists Discovered What Causes Dementia

An international team of researchers claims to have found a major cause of dementia - an incurable brain disease.


Scientists discovered a major cause of dementia which can help in the diagnosis and treatment of the illness. The researchers point to toxic levels of urea in the brain as being responsible for the brain damage that leads to dementia, an incurable neurodegenerative disease that causes an impairment of memory and thinking abilities.   

Urea is a byproduct of protein metabolism, produced by the liver to remove ammonia from the body. If you’re wondering - yes, urea is what’s excreted from the body in urine after being filtered by the kidneys.

The paper published by collaborating scientists from the UK, Australia, New Zealand the U.S. shows that Huntington’s Disease, one of seven major kinds of dementia that’s related to aging, has a direct relationship to urea levels in the brain as well as metabolic processes. A 2016 study by the same group also linked urea to Alzheimer’s. This proves, according to Professor Garth Cooper, who led the team from the University of Manchester in the U.K, that their discovery relates to different type of dementias. 

The observation that high urea levels set in before the onset of dementia can help doctors to one day diagnose and treat the disease.

“This study on Huntington’s Disease is the final piece of the jigsaw which leads us to conclude that high brain urea plays a pivotal role in dementia, said Professor Cooper. “Alzheimer’s and Huntington’s are at opposite ends of the dementia spectrum – so if this holds true for these types, then I believe it is highly likely it will hold true for all the major age-related dementias.” 

He added that more research is needed to understand how the urea levels get elevated.

The current study was conducted on human brains, donated by families for medical purposes as well as the brains of genetically modified sheep.

The international team included scientists from the University of Manchester, the University of Auckland, AgResearch New Zealand, the South Australian Research and Development Institute, Massachusetts General Hospital and Harvard University.

You can read their study in the Proceedings of the National Academy of Sciences.

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