Brain’s cleaning system raises dementia hopes

The Times

Tom Whipple Science Editor

Gerry Gajadharsingh writes:

 “One of the principles of Osteopathy is that “The Rule of the artery is supreme”, what this means is that circulation to and from a structure is critical for the self-healing/self-regulatory systems of the body to work efficiently. So, improving function in the upper neck (the connection between the head/brian and the rest of the body, may well help this process, i.e. improving circulation into the brain and helping the venous and lymphatic system take the waste metabolites out for delivery to the liver for breakdown and kidney for excretion.

 The research below suggests that a compromised ability of the brain to remove the build-up of waste products from metabolism may be one of the ways that these products build up in the brain and may contribute to cognitive decline.”

The brain’s cleaning system has been observed working naturally by scientists for the first time in research that may help in the fight against Alzheimer’s.

Researchers have been able to use MRI scanners to watch in real time as spinal fluid flushes waste products out of the brain and circulates them alongside blood vessels, to be removed by the body.

The system that performs this has only recently been discovered and its mechanism remains controversial, but it is believed to be crucial to brain health. Alzheimer’s disease is characterised by the build-up of waste products, and some scientists hypothesise that it could be caused by the brain’s inability to clean itself.

However, until now we have been unable to observe it in humans because all the techniques require some form of surgery. By tweaking MRI scanners, a team from UCL say they can observe it non-invasively, and now want to perform studies in humans to confirm that the system really does work as we think and to see if there is a link to dementia.

“The brain is a wonderful engine that allows us to think, feel, create emotions and give us sense of identity as well,” Mark Lythgoe, from UCL, told the Cheltenham Science Festival. “As with every engine it produces waste. This is one of the most metabolically active organs in body. One big question mark for the neuroscience community has been how does the brain cleanse itself?”

Scientists have long known about the body’s cellular cleaning mechanism, the lymphatic system. A corresponding “glymphatic system” for the brain was proposed in 2012. “In all textbooks there is no lymphatic system in the brain,” Ian Harrison, who works with Professor Lythgoe, said. “It is important because Alzheimer’s is characterised by the build up of waste products.”

By tuning an MRI scanner, he and his colleagues were able to watch the glymphatic system and show that it hitched a ride on blood vessels in the brain. As they pulsed, it pumped spinal fluid in and out of the brain, taking waste products with it.

This finding could explain the link between Alzheimer’s and poor sleep and exercise. When you are asleep, cells in the brain contract, allowing a greater flow of fluid. When you exercise, your heartbeat increases, helping to push the fluid along.

Professor Lythgoe said that they were now planning imaging experiments in humans and looking at drugs that may open up the channels used to clean the brain, and potentially prevent dementia.

He said that key to all of this had been the development of a way of seeing the system in action: “We need to be able to image it, to get it lighting up. We want to image this pathway early, to see if the pathway goes wrong and leads to Alzheimer’s disease.”

2018-06-13T04:38:55+00:00