Alzheimer’s is one of the diseases that we haven’t quite figured out yet. So far, there aren’t any reliable treatment methods for people who develop it, but scientists are working on preventative measures we can take to stop the condition from taking hold in the first place.
What is Alzheimer’s disease?
Alzheimer’s disease is a condition that is a result of Amyloid-beta buildup in the brain. People with Alzheimer’s tend to suffer from memory loss and degenerative cognitive function. Scientists know that Amyloid-beta is a protein that forms plaques in the brain, but they are unsure of how or why this happens.
The University of Manchester conducted a new study on the disease funded by the British Heart Foundation (BHF) that uncovers more of the mystery of Alzheimer’s. The researchers discovered that a smaller version of Amyloid-beta called Amyloid-β 1-40 (Aβ1-40) would accumulate in the walls of the brain’s small arteries and decrease blood flow to the brain. This discovery could inform the creation of new drugs that could help fight off the disease.
Narrowing arteries starve the brain
One of the reasons people with Alzheimer’s disease experience memory loss is because of the narrowing of the small arteries, called dial arteries, that cover the surface of the brain. These arteries are the pathways that regulate the flow of blood and oxygen to the brain. If they become too narrow, the brain doesn’t receive enough nourishment, which ultimately leads to memory loss.
The researchers looked at the pial arteries of older mice with Alzheimer’s and compared them with healthy mice. They found that the pial arteries of the mice with Alzheimer’s were narrower than those of the healthy mice, and also that they produced an excessive amount of (Aβ1-40). This is because the protein that usually sends a signal to widen the arteries (the BK protein) is deactivated by Aβ1-40 in cells lining blood vessels.
A breakthrough discovery
Treating Alzheimer’s disease has been a challenge for biomedical researchers. However, developing a deeper understanding of how Alzheimer’s affects blood vessels could be the breakthrough that we have all been waiting for.
“To date, over 500 drugs have been trialed as a cure for Alzheimer’s disease. All of the have targeted the nerves in the brain and none of them have been successful,” says the lead BHF-funded researcher and Clinical Senior Lecturer in Cardiovascular Sciences at the University of Manchester, Dr. Adam Greenstein. “By showing exactly how Alzheimer’s disease affects the small blood vessels, we have opened the door to new avenues of research to find an effective treatment.”
Next steps
To further their knowledge, the researchers will work on pinpointing exactly which part of Aβ1-40 deactivates the BK protein, and then develop drugs to stop this process.
Source study: Proceedings of the National Academy of Sciences—Functionally linked potassium channel activity in cerebral endothelial and smooth muscle cells is compromised in Alzheimer’s disease
