The latest hypothesis about Alzheimer is a new direction for research: currently associated with physical deterioration in the brain, the degenerative disease might actually originate outside the brain, as a cascade of breakdowns that begin elsewhere in the body, scientists say.
Until now, scientists have generally believed that deposits of amyloid-beta found in the brain, which coalesces into “plaques” that disrupt neurological function are generated locally. But the protein can be synthesized in peripheral tissues anywhere in the body. In a medical study, a team of Canadian and Chinese scientists surgically joined healthy mice to mice that had been genetically modified with high concentrations of amyloid-beta. After a year, the healthy mice developed the same telling neurological symptoms as the genetically modified mice.
Besides the brain, amyloid-beta is produced in blood platelets, blood vessels and muscles, and its precursor protein is found in several other organs British Columbia psychiatry professor Dr. Weihong Song and his team believe that amyloid-beta originating in the bloodstream can spread to the brain and bring on the neuron deficits that cause Alzheimer which can only be officially diagnosed via autopsy. By testing for high concentrations of amyloid-beta in the bloodstream, researchers might find a way to catch it before it ever reaches the brain. “I can’t say it’s in two or it’s in three years there will be a treatment…but in the future there could be drugs designed to attack the peripheral side,” Prof. Song says. The findings were published this week in Molecular Psychiatry.