When brain cells start showing too much of the amyloid protein that is the hallmark of Alzheimer’s disease, cells that normally nourish and protect brain cells deliver a suicide package instead, researchers report.
According to researchers at the Georgia Health Sciences University, amyloid is excreted by all neurons, but rates dramatically increase in Alzheimer’s. In response to the excessive amyloid, astrocytes, which deliver blood, oxygen and nutrients to neurons in addition to hauling off some of the garbage, get activated and inflamed.
In a new study, the researchers have shown astrocytes also respond by packaging the lipid ceramide with the protein PAR-4, which can do damage on their own, but together are a more “deadly duo,” said Dr. Erhard Bieberich, a biochemist at the Medical College of Georgia at the university.
“If the neuron makes something toxic and dumps it at your door, what would you do?” said Bieberich, corresponding author of the study published in the Journal of Biological Chemistry. “You would probably do something to defend yourself.”
The researchers hypothesize that this lipid-coated package ultimately kills them both, which could help explain the brain-cell death and shrinkage that occurs in Alzheimer’s.
“If the astrocytes die, the neurons die,” Bieberich explained.
An avenue for future pursuit is whether a ceramide antibody could be a viable treatment for Alzheimer’s, he added.