New Alzheimer’s treatment fully restores memory function
Of the mice that received the treatment, 75 percent got their memories back.
BEC CREW 18 MAR 2015
Australian
researchers have come up with a non-invasive ultrasound technology that
clears the brain of neurotoxic amyloid plaques - structures that are
responsible for memory loss and a decline in cognitive function in
Alzheimer’s patients.
If a person has Alzheimer’s disease, it’s
usually the result of a build-up of two types of lesions - amyloid
plaques, and neurofibrillary tangles.
Amyloid plaques
sit between the neurons and end up as dense clusters of beta-amyloid
molecules, a sticky type of protein that clumps together and forms
plaques.
Neurofibrillary tangles
are found inside the neurons of the brain, and they’re caused by
defective tau proteins that clump up into a thick, insoluble mass. This
causes tiny filaments called microtubules to get all twisted, which
disrupts the transportation of essential materials such as nutrients and
organelles along them, just like when you twist up the vacuum cleaner
tube.
As we don’t have any kind of vaccine or preventative measure
for Alzheimer’s - a disease that affects 343,000 people in Australia,
and 50 million worldwide - it’s been a race to figure out how best to
treat it, starting with how to clear the build-up of defective
beta-amyloid and tau proteins from a patient’s brain. Now a team from
the Queensland Brain Institute (QBI) at the University of Queensland
have come up with a pretty promising solution for removing the former.
Publishing in
Science Translational Medicine,
the team describes the technique as using a particular type of
ultrasound called a focused therapeutic ultrasound, which non-evasively
beams sound waves into the brain tissue. By oscillating super-fast,
these sound waves are able to gently open up the blood-brain barrier,
which is a layer that protects the brain against bacteria, and stimulate
the brain’s microglial cells to move in. Microglila cells are basically
waste-removal cells, so once they get past the blood-brain barrier,
they’re able to clear out the toxic beta-amyloid clumps before the
blood-brain barrier is restored within a few hours.
The team reports
fully restoring the memories of 75 percent
of the mice they tested it on, with zero damage to the surrounding
brain tissue. They found that the treated mice displayed improved
performance in three memory tasks - a maze, a test to get them to
recognise new objects, and one to get them to remember the places they
should avoid.
"We’re extremely excited by this innovation of
treating Alzheimer’s without using drug therapeutics," one of the team,
Jürgen Götz,
said in a press release.
"The word ‘breakthrough’ is often misused, but in this case I think
this really does fundamentally change our understanding of how to treat
this disease, and I foresee a great future for this approach."
The
team says they’re planning on starting trials with higher animal
models, such as sheep, and hope to get their human trials underway in
2017.
You can hear an ABC radio interview with the team
here.
READ THE ARTICLE HERE
