stanford | A new study led by investigators at the Stanford University School of Medicine
has implicated the blocking of endocannabinoids — signaling substances
that are the brain’s internal versions of the psychoactive chemicals in
marijuana and hashish — in the early pathology of Alzheimer’s disease.
A substance called A-beta — strongly suspected to play a key role in
Alzheimer’s because it’s the chief constituent of the hallmark clumps
dotting the brains of people with Alzheimer’s — may, in the disease’s
earliest stages, impair learning and memory by blocking the natural,
beneficial action of endocannabinoids in the brain, the study
demonstrates. The Stanford group is now trying to figure out the
molecular details of how and where this interference occurs. Pinning
down those details could pave the path to new drugs to stave off the
defects in learning ability and memory that characterize Alzheimer’s.
In the study, published June 18 in Neuron,
researchers analyzed A-beta’s effects on a brain structure known as the
hippocampus. In all mammals, this midbrain structure serves as a
combination GPS system and memory-filing assistant, along with other
duties.
“The hippocampus tells us where we are in space at any given time,” said Daniel Madison,
PhD, associate professor of molecular and cellular physiology and the
study’s senior author. “It also processes new experiences so that our
memories of them can be stored in other parts of the brain. It’s the
filing secretary, not the filing cabinet.” Fist tap Dale.
