UCD researchers link CO2 levels
in the brain to seizures and chronic fatigue
Researchers at the University of Colorado Denver have discovered how carbon dioxide (CO2) affects excitability
levels in the brain – levels that could cause epileptic seizures – or
could put you to sleep. The findings were published in the Dec. 22
issue of Neuron.
For the study, brain tissue was exposed to varying levels of CO2
to determine the effect of CO2 on seizure propensity. The research
team found an increase in CO2 reduced the excitability of brain cells while
decreases
in CO2 increased excitability.
“In this study, we found that CO2 influenced the excitability of neurons
in the brain through two molecules – ATP and adenosine,” said Chris
Dulla, PhD, primary investigator of the study. “ATP is the molecule that
lets cells store energy and adenosine is the same molecule that caffeine blocks
in the brain to make us feel more alert. Our study showed a relationship between
the molecules the brain uses to store energy and the risk of having a seizure
for those susceptible to seizures.”
“
A decrease in CO2 led to a decrease of adenosine concentration in the brain and
acts in the same way a cup of coffee might on the brain – it makes the
brain more alert. Conversely, an increase in CO2 would increase adenosine concentrations
in the brain, which would make a person more lethargic,” said Kevin Staley,
MD, co-author of the paper.
When asked how this research might apply to other areas of medical research
or future studies, Staley said: “Patients undergoing routine electroencephalography
(EEG) are always asked to hyperventilate. We have known for more than 50 years
that hyperventilation induces seizures, but we haven’t known why. Our findings
provide the link between hyperventilation and the brain alterations recorded
on the EEG. This new knowledge will help us develop new strategies to treat seizures,
and could lead to the design of new drugs and focus attention on new classes
of genetic mutations that could cause epilepsy.”
