14 DAY TRIAL // A team of investigators in the United Kingdom announces the development of a new drug, that experts say is capable of reversing memory decline brought on by old age in animal models.
The experimental chemical works by reducing levels of stress hormones called glucocorticoids, which have been linked to impairing the brain's learning and memorizing abilities in past studies.
Researchers at the University of Edinburgh say that these chemicals act on the brain of mice over time, and believe that a similar series of processes is taking place in the human brain as well.
“What's most surprising is that even short-term inhibition was able to reverse memory loss in old mice,” explains scientist Jonathan Seckl.
The expert holds an appointment as a professor of molecular medicine at the university. “I don't think people had realized this was so reversible. It takes [the animals] back to being relatively young,” he adds.
Seckl says that the new work may be used to lay out the groundwork for a new series of therapies and drugs that could have the same effects on humans as well.
UE experts say that they want to start human clinical trials next year, and add that they are currently researching a compound closely related to the one that functioned so well on the unsuspecting rodents.
Interestingly, glucocorticoids play a role in aiding memory formation under stressful conditions, but higher levels can lead to increased memory loss, especially with old age.
Scientists have yet to discover the intricacies underlying this mechanisms, but the leading theory is that the excess amounts of the chemical affect the brain by leaving it more vulnerable to decay.
The UE team believes that an enzyme called 11β-hydroxysteroid dehydrogenase type 1 (11 β-HSD1) is the key to reducing the effects glucocorticoids have on the brain.
“This enzyme acts as an intracellular amplifier of glucocorticoids. If you take out the amplifier, you still have stress hormones, but they shout less loudly and cause less wear and tear,” Seckl explains.
Therapies conducted with drugs that acted on this enzyme “returned mice to the equivalent of when they were young and fully functioning,” explains UE researcher Brian Walker.
“It's important to emphasize that we are trying to target the pathology – the role that glucocorticoids play in age-related memory decline – not just globally improving memory,” he goes on to say.
Details of the new investigation appear in last week's issue of the esteemed medical Journal of Neuroscience, Technology Review reports.