AMAZING PROGRESS ON ALZHEIMER’S DISEASE IN AMAZING ISRAEL: DAVID SHAMA

http://www.timesofisrael.com/researchers-find-major-clue-toward-alzheimers-cure/
Researchers find major clue toward Alzheimer’s cure

Brain hyperactivity caused by protein binding may be important factor
in disease’s development: Israeli team

Researchers at Tel Aviv University believe they have tracked down one
of the main reasons for the seizures, memory loss and cognitive
impairment that Alzheimer’s patients suffer. Following up on the
finding may show the way toward a cure for the debilitating disease
that hobbles millions of seniors.

The research shows how a molecular mechanism involving proteins
interferes with brain neuron function and shifts them into dangerous
overdrive. The discovery gives researchers a clue towards solving the
Alzheimer’s puzzle, according to Dr. Inna Slutsky of TAU’s Sackler
Faculty of Medicine and Sagol School of Neuroscience.

“We have now identified the molecular players in hyperactivity,” said
Slutsky, adding that the discovery “may help to restore memory and
protect the brain.”

The effects of Alzheimer’s have been widely observed — clumps of
proteins build up in the brains of patients, interfering with
cognitive functions. The challenge has been to find the mechanism
behind the progression.

Slutsky published the results of a study on how brain hyperactivity
affects Alzheimer’s patients in the latest edition ofCell Reports. The
study was supported by European Research Council, Israel Science
Foundation, and Alzheimer’s Association grants.

The culprit, according to research by Slutsky’s team, appears to be
enhanced neuronal activity in Alzheimer’s patients, caused by a
molecular mechanism involving amyloid precursor protein (APP). APP is
well-known by researchers for producing a substance called
amyloid-beta. APP also acts as a receptor for the substance. According
to the study, the binding of amyloid-beta to pairs of APP molecules
triggers a “signaling cascade,” in which messages shared by brain
cells are amplified, elevating neuronal activity and essentially
“short-circuiting” the brain’s communications network.

Doctors have observed this hyperactivity in the hippocampus — the area
of the brain that controls learning and memory — among early stage
Alzheimer’s patients, as well as in individuals suffering from mild
cognitive disorders, like poor memory. Studies of mice have shown how
the hyperactive hippocampal neurons precede the formation of amyloid
plaque — the protein clumps that may block cell-to-cell signaling at
synapses — leading to the eventual death of brain cells and advanced
Alzheimer’s.

In a five-year search for the underlying cause of neuronal
hyperactivity, TAU doctoral student Hilla Fogel and postdoctoral
fellow Samuel Frere found that amyloid-beta is essential for the
everyday transfer of information through the nerve cell networks.
However, if the level of amyloid-beta is even slightly increased, it
causes neuronal hyperactivity and greatly impairs the effective
transfer of information between neurons.

Using cutting-edge technology and in collaboration with Prof. Joel
Hirsch of TAU’s Faculty of Life Sciences, Prof. Dominic Walsh of
Harvard University, and Prof. Ehud Isacoff of University of California
Berkeley, the researchers found that the binding of amyloid-beta
triggers a change in the APP molecule interactions, leading to an
increase in calcium flux and higher glutamate release — in other
words, brain hyperactivity.

The problem emerges when too much of this binding takes place — so the
key, according to the research, is to figure out a way to interfere
with the binding of amyloid-beta to APP. “TAU postdoctoral fellow
Oshik Segev is now working to identify the exact spot where the
amyloid-beta binds to APP and how it modifies the structure of the APP
molecule,” said Slutsky. “If we can change the APP structure and
engineer molecules that interfere with the binding of amyloid-beta to
APP, then we can break up the process leading to hippocampal
hyperactivity. This may help to restore memory and protect the brain.”
Years of research are likely still needed before this finding could be
turned into practice.

Slutsky added, “One way of doing that may be a reduction of an element
called “tau” (microtubule-associated protein), another key player in
Alzheimer’s, which reverses synaptic deficits and decreases abnormal
brain activity in animal models. It will be crucial to understand the
missing link between APP and ‘tau’-mediated signaling pathways leading
to hyperactivity of hippocampal circuits. If we can find a way to
disrupt the positive signaling loop between amyloid-beta and neuronal
activity, it may rescue cognitive decline and the conversion to
Alzheimer’s disease.”

http://www.timesofisrael.com/researchers-find-major-clue-toward-alzheimers-cure/

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