Memory enhanced by sports-cheat drug

Sep 09, 2008

A drug used to increase blood production in both medical treatments and athletic doping scandals seems also to improve memory in those using it. New research published in the open access journal BMC Biology shows that the memory enhancing effects of erythropoietin (EPO) are not related to its effects on blood production but due to direct influences on neurons in the brain. The findings may prove useful in the treatment of diseases affecting brain function, such as schizophrenia, multiple sclerosis, and Alzheimer's.

Patients given EPO to treat chronic kidney failure had been observed to have improved cognition after starting the drug. "These effects of EPO were thought to result from the blood-boosting effects of the drug", explains Hannelore Ehrenreich at the Max Planck Institute, "but the finding of receptors for EPO on nerve cells in the brain suggests that some other mechanism might be involved."

To investigate the mechanisms of EPO-enhanced cognition, the researchers injected mice with EPO every other day for three weeks (11 doses) to test the effects of long-term exposure. After the treatment period, mice given EPO had better memory in some situations than did mice that had been given a placebo instead. The improvement in memory lasted up to three weeks from the last EPO dose and outlasted increased blood-cell production, but had disappeared by four weeks. Mice given three doses saw no benefit with respect to memory improvement.

"Young mice systematically treated with EPO for three weeks have improved memory, similar to the dramatic improvements observed in endurance and muscular performance athletes who use EPO to boost performance", says Ehrenreich. The specific memory improvements were associated with the hippocampus, a structure in the brain involved in learning and memory, among other functions.

The researchers did a series of experiments on hippocampal tissue taken from the mice and found that EPO directly affected the neurons in this structure. "EPO had pronounced effects on short-term and long-term plasticity in the hippocampus as well as on synaptic transmission", the researchers report. "Treatment with EPO seems to increase the number of inhibitory circuits, which actually increases the efficiency of transmission of excitatory nerve impulses in specific neurons, resulting in greater short-term and long-term plasticity in memory pathways in the hippocampus."

These findings begin to shed light on the mechanisms of improvements in cognition seen in patients with schizophrenia and multiple sclerosis as a result of treatment with this drug. As well as working to refine these findings, further studies might also investigate the effects of EPO on other brain regions that might be associated with improvements in motor functions in multiple sclerosis, and investigate the potential of using EPO or targeting the networks involved in EPO-generated neuronal plasticity in the treatment of neurodegenerative diseases.

Source: BioMed Central

Explore further: US appeals court upholds delay in Alzheimer's drug swap

Related Stories

SLAC gears up for dark matter hunt with LUX-ZEPLIN

24 minutes ago

Researchers have come a step closer to building one of the world's best dark matter detectors: The U.S. Department of Energy (DOE) recently signed off on the conceptual design of the proposed LUX-ZEPLIN (LZ) ...

Feeling the pain and joys of commuting

25 minutes ago

Long hours commuting to and from work can generate fear, distrust and depression and can change the way people interact with their families and work colleagues, a new study from The Australian National University ...

Orchid seductress ropes in unsuspecting males

5 minutes ago

A single population of a rare hammer orchid species known as a master of sexual deception appears to have recently evolved to seduce a new and wider-spread species of impressionable male wasps.

Peat moss, a necessary bane

35 minutes ago

The temperature balance on Earth may be dependent on a conspicuous creation that sours life for everyone around, guzzles more than a sponge and produces lots of offspring that behave likewise. And you thought ...

Recommended for you

US appeals court upholds delay in Alzheimer's drug swap

May 22, 2015

A federal appeals court has rejected a drug manufacturer's appeal and affirmed a judge's order that Actavis PLC keep distributing its widely used Alzheimer's medication until after its patent expires this summer.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.