Study Finds Evidence of Link Between Absence Seizures and Myelin Plasticity
Results from a novel study presented at the American Epilepsy Society Annual Meeting revealed an association between seizures and myelin plasticity, opening exciting possibilities for future research. Researchers documented an increase in both the total number of myelinated fibers as well as thickening of the myelin sheath in mice and rats which experienced absence seizures, a seizure type characterized by brief periods of behavioral arrest. Administering antiseizure medication to these animals decreased seizure activity as well as the development of aberrant myelination. These findings suggest that seizure events may result in structural changes in the brain which can contribute to the development of more frequent or intense seizures.
In their study of rats and mice with general epilepsy, researchers used MRI along with histologic methods to analyze myelin structure to understand whether there was a relationship between abnormal patterns of neuronal activity as seen with epilepsy and neuronal architecture and networks. Aberrant myelination was detected in animals with absence type seizures in specific regions of the brain affected by such seizures, and administration of antiseizure medications reduced aberrant myelination processes and seizure activity.
According to lead author of the study, Dr. Juliet K. Knowles, Stanford University, “To our knowledge, this is the first description of maladaptive myelin plasticity in epilepsy or any neurologic disease...We hope this information will provide new insights for epilepsy that doesn’t respond to treatment.”
Expanding their research into a different group of mice, researchers found that by blocking myelination either through pharmacotherapy or genetic modification resulted in a significant reduction in the number of seizures experienced.
“We’re now studying specific mechanisms by which neurons involved in seizures communicate with myelin-forming cells, and different methods for interrupting maladaptive myelination,” said Dr. Knowles. “We also are developing MRI methods that may allow us to study this process in humans, including how myelin changes throughout the brain and over time.”