Hypertension Drugs: Alzheimer's Perk?

Oct. 26, 2007 -- Certain hypertension (high blood pressure) drugs may counter Alzheimer's disease.

That news comes from lab tests on mice, not people.

The researchers who conducted those tests aren't ready to recommend blood pressure drugs for Alzheimer's prevention, but they see good reason to test the possibility.

"The use of these drugs for their potential anti-Alzheimer's disease role is still highly experimental," says Giulio Maria Pasinetti, MD, PhD, in a news release.

Pasinetti -- who works at New York's Mount Sinai School of Medicine -- had read previous studies linking high blood pressure drugs to reduced risk of Alzheimer's disease.  

Those studies were based on patients' medical records, not direct tests of the drugs. So Pasinetti's team headed to their lab to do some experiments.

Alzheimer's Experiment

Pasinetti and colleagues pitted 55 hypertension drugs against beta-amyloid proteins in test tubes.

Beta-amyloid proteins form plaque found in brains ravaged by Alzheimer's disease.

Seven drugs thwarted the buildup of beta-amyloid proteins.

Those drugs, which come from various classes of hypertension drugs, are:

• Propranolol hydrochloride (sold generically and as Inderal)
• Carvedilol (sold generically and as Coreg)
• Valsartan (sold as Diovan)
• Losartan (sold as Cozaar)
• Nicardipine hydrochloride (sold generically and as Cardene)
• Amiloride hydrochloride (sold generically and as Midamor)
• Hydralazine hydrochloride (sold generically and as Apresoline)

Further lab tests showed that one of those seven drugs, Diovan, hindered certain beta-amyloid ingredients.

Diovan Tested in Mice

The researchers then tested Diovan in mice that were genetically at risk for Alzheimer's disease.

Some of the mice drank water laced with Diovan. Their Diovan dose was lower than that used for people with high blood pressure.

For comparison, other mice got ordinary water without Diovan.

After drinking their assigned water for 11 months, the mice took a memory test in which they had to learn and remember the path through a watery maze.

The mice that drank the Diovan water fared best in the maze test.

But when the researchers tested mice without the dementia gene glitch, Diovan treatment didn't help or hurt the mice navigate the watery maze.

There is no evidence that Diovan prevents or slows dementia in people, but the findings in mice may inspire such a study in people at high risk for Alzheimer's, Pasinetti's team suggests.

Their study appears in The Journal of Clinical Investigation.