A drug currently used to treat hypoglycemia, and once commonly prescribed in the 1970’s and 80’s to help with hypertension, may have a new use: treating Alzheimer’s patients.
Researchers at the National Institute on Aging (NIA) have found that the drug, diazoxide, improves memory and learning in mice engineered to have Alzheimer’s.
Scientists discovered that the drug stabilizes nerve cells in the brain and prevents their destruction, a common occurrence under Alzheimer’s conditions. Diazoxide also enhances blood flow through the brain and keeps under control the two proteins beta-amyloid and tau, whose buildup in the brain is considered a hallmark of the disease.
“These intriguing findings open new avenues of basic research that may increase our understanding of how modulating the electrical activity of nerve cells may slow the damage wrought by Alzheimer’s disease pathology,” said NIA Director Richard J. Hodes, M.D.
“More research will be needed before we can determine whether this may be a potential therapy for Alzheimer’s.”
For the study, NIA scientists analyzed two groups of Alzheimer’s mice: one group was given diazoxide in drinking water and the other was given a placebo. Once eight months had passed, the diazoxide mice performed better than the placebo group in a learning and memory test.
The brain tissue of the diazoxide mice revealed that the drug may have hindered toxic cellular changes common in Alzheimer’s disease, with fewer deposits of the dangerous proteins, less oxidative stress damage, and better blood flow.
“To better understand the complex biological mechanisms by which diazoxide may exert a positive effect on nerve cells, we then studied the effects of diazoxide on cultured nerve cells,” said Mark P. Mattson, Ph.D., chief of NIA’s Laboratory of Neurosciences in Baltimore.
The study shows that diazoxide also triggers and opens cell channels that enable the flow of potassium, which in turn calms electrical nerve cell activity in areas of the brain associated with learning and memory. It also lowers excessive calcium, often found in nerve cells in brains affected by Alzheimer’s.
Importantly, these benefits occurred with a dose of diazoxide low enough to avoid producing a significant decrease in blood pressure, Mattson noted.
The study can be found in the Nov. 15, 2010, print edition of the Journal of Alzheimer’s Disease.
Source: National Institutes of Health