New discovery could provide better treatment of epilepsy and cardiac arrhythmia
Nerve cells communicate with their surroundings through channels in the cell membrane, where electrical impulses are sent through ions – charged atoms. Established medicine, for example local anaesthesia, works through blocking these channels, thus obstructing communication. Medicines for epilepsy functions in a similar fashion – they dampen nerve impulses through blocking ion channels.
But almost a third of all those who suffer from epilepsy are not helped by current medicines, which moreover have undesirable side effects. LiU research Fredrik Elinder, professor of molecular neurobiology, and his graduate student Sara Börjesson have discovered and charted a mechanism that makes it easier for the cell to open and close its ion channels itself.
“Instead of rolling a stone in front of the doorway, which current medicine does, we could say that we’ve found out how to use the doorknob to close the door,” Elinder says.
“It’s a question of stimulating the cell’s own mechanism that opens and closes the ion canals, through letting electrically charged substances bind to the components in the cell membranes that regulate this. These are substances like polyunsaturated fatty acids, for example omega-3 and omega-6. It was the successful treatment of an epileptic child with these fatty acids that put the researchers on the right track,” he relates.
“Paediatric neurologists discovered years ago that children got much better with a high-fat diet – what’s called a ketogenic diet.”
Now he and his colleagues have found a partial explanation for this. Polyunsaturated fats bind in the right way at the right place to be able to affect the nerve cell’s own mechanisms for opening and closing ion channels. LiU researchers have dubbed their discovery the lipoelectric mechanism.
“We’ve found an entirely new mechanism and an entirely new binding site,” Elinder says. “The method of attack is also more subtle. We’re working with the body’s own functions, which could reduce the risk of side effects.
“The work is now going further, looking for molecules that have these specific properties and which could function as medicine. Credit where credit is due, of course, but fatty acids strike too broadly,” he says. He won’t predict how long it will take to develop a medicine, however.
“It could take anywhere from five to twenty years. We’ve still got plenty of steps left in the process.”
Text: Anika Agebjörn
Last updated: 2012-12-10