Cholesterol-Lowing Drug Reverses Memory Deficit in Mice
A common statin drug taken by millions of Americans to lower their cholesterol level also may reverse certain types of learning deficits, according to a news study in mice.
The statin drug lovastatin dramatically improved memory and restored normal cognitive function in mice specially bred to have a genetic disorder called Noonan syndrome. People with this disorder tend to have developmental delays as well as heart defects, unusual facial features and short stature.
Approximately 1 in 2,000 babies are born with Noonan syndrome. Because lovastatin already is an FDA-approved drug for heart health and is generally considered safe, the researchers who did the study said they hope that they soon can test lovastatin in children and adults with learning disabilities caused by Noonan syndrome or related disorders.
"Noonan syndrome interferes with the changes in brain cells needed for learning, which results in learning deficits," said Alcino Silva, a professor of neuroscience at the David Geffen School of Medicine at UCLA and senior author on the paper. Lovastatin acts "on the root of the problem and reverse[s] these deficits. This enables the process of learning to physically change the brain and create memory," he said. [11 Facts Every Parent Should Know About Their Baby's Brain]
The research team had previously discovered that Noonan syndrome involves a hyper expression of a protein called Ras, which disrupts communication in the brain. Statins, in general, lower cholesterol by blocking the synthesis of certain fat molecules that Ras needs to function.
But lovastatin might be "unique amongst the statins" in its ability to cross the blood-brain barrier at therapeutic levels to improve learning in people with Noonan syndrome, Silva told Live Science.
"The study of [syndromes involving the Ras protein] taught us that too much or too little Ras activity can both be bad for health, including brain function," Silva said.
Lovastatin also may improve learning in people with another Ras-related syndrome called neurofibromatosis type I, Silva said.
Other studies on statins have revealed conflicting results concerning brain function. The FDA has said that statins' side effects may include confusion and memory loss, based largely on patient complaints. Yet several recent, large studies have found, conversely, that statins may prevent dementia and slow the progression of Alzheimer's disease through a mechanism not well understood.
While the latest finding is reminiscent of "Flowers for Algernon," the Daniel Keyes novel about a laboratory mouse that increases its intelligence by artificial means, the lovastatin drug does not provide superintelligence, but rather could possibly reverse a disorder to enable normal learning.
Nevertheless, Silva said he sees great promise for the use of lovastatin and Ras-related learning disorders.
"Intellectual disabilities only affect 30 to 50 percent of [Noonan syndrome] patients," Silva said. "In some patients, the intellectual disabilities are severe, but in most they are not. However, even a mild intellectual disability can be life-changing, limiting what the affected person could otherwise be and achieve."