Pharmaceutical Business review

Ampakines found to help reverse memory loss

A group of scientists conducted studies on rats with a class of drugs known as ampakines. Ampakines were developed in the early 1990s by University of California researchers to treat age-related memory impairment and may be useful for treating a number of central nervous system disorders, such as Alzheimer’s disease and schizophrenia.

In this study, the researchers showed that ampakine drugs continue to reverse the effects of aging on a brain mechanism thought to underlie learning and memory even after they are no longer in the body. They do so by boosting the production of a naturally occurring protein in the brain necessary for long-term memory formation.

The researchers treated two groups of middle-aged rats twice a day for four days with either a solution that contained ampakines or one that did not. They then studied the hippocampus region of the rats’ brains, an area critical for memory and learning. They found that in the ampakine-treated rats, there was a significant increase in the production of brain-derived neurotrophic factor (BDNF), a protein known to play a key role in memory formation. They also found an increase in long-term potentiation (LTP), the process by which the connection between the brain cells is enhanced and memory is encoded.

Significantly, restoration of LTP was found in the middle-aged rats’ brains even after the ampakines had been cleared from the animals’ bodies. The drug used in the injections has a half-life of only 15 minutes; the increase in LTP was seen in the rats’ brains more than 18 hours later.

According to the researchers, this study suggests that pharmaceutical products based on ampakines can be developed that do not need to be in the system at all times in order to be effective. Most drugs used to deal with central nervous system disorders, such as Parkinson’s disease, are only effective when they are in the body.

Further studies will be needed to determine exactly how long the effect on LTP will be maintained after the ampakines leave the system.

“This is a significant discovery,” said Christine Gall, professor of anatomy and neurobiology at the university. “Our results indicate the exciting possibility that ampakines could be used to treat learning and memory loss associated with normal aging.”

The study was funded by grants from the US National Institute of Neurological Disorders and Stroke, the National Institute on Aging, and from National Institute of Mental Health. The ampakine drug was provided by Cortex.