The researchers looked at the biochemical effects of statins in reducing damage from Alzheimer's disease. Their study is published in today's issue of the journal Atherosclerosis.
"Statins block the vasoconstrictive effects of the A-beta protein a critical protein involved in Alzheimer's disease pathology," said Daniel Paris, PhD, first author of the study and an assistant professor at the USF Roskamp Institute. "These drugs appear to have anti-inflammatory properties, independent of their benefit in lowering cholesterol, that may help protect against dementia."
Recently, the risk of developing Alzheimer's disease has been shown to be reduced in populations treated with statins, although the reason is unclear. Other studies indicate that high cholesterol or other cardiovascular conditions also increase the risk for Alzheimer's disease.
The Roskamp researchers, searching for clues to understand the preventive action of statins, were struck by the similar effects of cholesterol and the A-beta protein (A) in blood vessels. Both compounds promote the constriction of blood vessels through a similar mechanism. They hypothesized that the same drugs that inhibit the production of cholesterol might affect A's stimulation of inflammatory substances that result in blood vessel constriction.
The researchers studied the effects of two statins most commonly used to treat high cholesterol mevinolin (lovastatin) and mevastatin (compactin).
A appears to be toxic to human neuronal cells cultured in the laboratory. But, when these same neurons were treated with mevastatin, the neurotoxicity normally induced by A was prevented, the researchers found.