Washington : Two proteins which work together in the brain’s blood vessels present a double whammy in Alzheimer’s disease.
Not only do they lessen blood flow in the brain, they also reduce the rate at which the brain is able to remove amyloid beta, the protein that builds up in toxic quantities in the brains of patients with the disease.
These two proteins are well known to cardiovascular researchers, SRF (serum response factor) and myocardin. The two work together within smooth muscle cells that line blood vessels to activate genes that are necessary for smooth muscle to function properly.
“This is quite unexpected,” said Berislav Zlokovic, neuroscientist and a senior co-author of the study. “On the other hand, both of these processes are mediated by the smooth muscle cells along blood vessel walls, and we know that those are seriously compromised in patients with Alzheimer’s disease, so perhaps we shouldn’t be completely surprised.”
The new findings are the result of a seven-year collaboration between two labs. Zlokovic heads the Center for Neurodegenerative and Vascular Brain Disorders, (CNVBD) looking at molecular roots of diseases like Alzheimer’s.
Several years ago, after he found that several genes well known to cardiovascular researchers seemed to be especially affected in Alzheimer’s patients, he turned to Joseph Miano, to help analyse the findings.
Miano is interim director of Aab Cardiovascular Research Institute and associate professor of Medicine, and he is senior co-author of the new study.
“To some, it might seem odd that a cardiovascular group would intersect with a neuroscience group to study Alzheimer’s disease,” Miano said.
“But there’s a great deal of evidence to suggest that Alzheimer’s disease is a problem having much to do with the vascular plumbing. And Rochester is the type of institution where partnerships like these are easy to strike up,” he added.
For 15 years Zlokovic’s lab has focused on the molecular mechanisms regulating blood supply and the role of the blood-brain barrier in the development of Alzheimer’s disease, said a release of CNVBD.
Normally, amyloid is picked up efficiently by blood vessels that then whisk the toxic trash away. But in Alzheimer’s disease, the system no longer is able to keep up with the body’s production of the substance. The molecular trash accumulates, and Zlokovic and others believe the buildup kills brain cells.
These findings were published in Nature Cell Biology.