New Research Uncovers Clue to Help Down Syndrome Patients Increase Learning Capacity

Researchers at the University of Colorado at Denver and Health Sciences Center (UCDHSC) may have found a way to reverse the learning deficit associated with Down syndrome. The findings could potentially lead to a new therapy to increase the learning capacity of children and adults born with the genetic disorder. The findings are published in the Aug. 15 advance online edition of Neuropsychopharmacology, a publication of the Nature Publishing Group.
The UCDHSC research tested the effectiveness of memantine, an FDA-approved drug already being used to treat patients with Alzheimer’s disease. When the drug was used on mice with an animal model of Down syndrome, researchers found the mice to have better memory retention. This authors note this “is the first instance in which acute injection of a drug agent has improved the behavioral performance of Down syndrome mice in a test of learning and memory,” and that the findings are promising from a therapeutical perspective.

The study was conducted using a chamber to measure the learning retention of mice with Down syndrome against healthy control mice. Once inside the chamber, the mice were exposed to a brief and mild electric stimulus carefully designed to produce an unpleasant feeling without causing harm.

“When run through this type of experiment, typical control mice generally are able to associate being in the chamber with the unpleasant stimulus,” said Alberto Costa, MD, PhD, associate professor of medicine and neuroscience at UCDHSC’s School of Medicine and lead author of the study. “After being exposed to the stimulus, the control mice would experience freezing behavior when they were put back into the chamber 24 hours later. The mice with Down syndrome were not able to recall the stimulus at all. Instead, they would stroll around the chamber the same way as mice that had never been exposed to it.”

After administering just two doses of the drug memantine, the study found that the mice with Down syndrome displayed a statistically indistinguishable amount of freezing behavior, much like the behavior observed in the control mice.

The first dose of memantine was given 15 minutes before the mice were exposed to the stimulus for the first time and the second dose was given to the mice 24 hours later, 15 minutes before they were put back in the chamber.

“In a separate set of experiments, the research team found that the most important dose of memantine seems to be the one taken before the animals are first exposed to the stimulus inside the chamber, which argues for a more important role of the drug on memory formation, as opposed to memory retrieval,” said Costa.

Costa, also the parent of a 12-year-old child with Down syndrome, hopes to receive institutional review board approval to lead a team of physicians and psychologists in Denver in a pilot, placebo-controlled, double-blind clinical trial in which they will attempt to translate the knowledge acquired from this research into a potential therapy for the cognitive deficits associated with Down syndrome.

“After 11 years working in the field of Down syndrome, I feel fortunate to finally be in a position of being able to use scientific research to try to help improve the quality of the life of people who share the same genetic disorder as my daughter,” he said.

This Down syndrome research was funded by the Anna & John J. Sie Foundation, the Coleman Institute for Developmental Disabilities, the Mile High Down Syndrome Association, the Colorado Springs Down Syndrome Association, and the National Institutes of Health.

Source: www.HealthNewsDigest.com