Irvine, Calif., March 25, 2008 – An increased number of neuron “hubs” in the epileptic brain may be the root cause for the seizures that characterize the disorder, according to a UC Irvine study.
Researchers Robert Morgan and Ivan Soltesz with the Department of Anatomy and Neurobiology identified that these hubs – a small number of highly connected neurons – are formed in the hippocampus during the transition from a healthy brain to an epileptic one. The increased number of connections among these hubs, they found, circulate and amplify signals to such a degree that they overwhelm brain networks, leading to epileptic seizures.
The study appears this week in the online early edition of the Proceedings of the National Academy of Sciences.
“The structure of the epileptic brain differs substantially from that of a healthy one, and our discovery of this hub network offers insight into how epilepsy may develop,” Morgan said. “By establishing therapeutic measures that can selectively target these hub cells, we may be able to create a treatment for epilepsy.”
The researchers used a computer model of a moderately injured hippocampus – the brain region involved in many forms of epilepsy – to create the signaling networks that mimic an epileptic brain, and they found that one featuring a greater number of neuronal hubs promoted the onset of seizure.
By comparing this model with previous animal model studies of epilepsy, they identified these hubs as the network conduits for seizures. Soltesz said that previous studies revealed the existence of these hubs but did not define their role.
“This study is a great example of integrating data from biomedical informatics with basic and clinical research to advance the effort to understand and potentially treat disease and disorders like epilepsy,” added Soltesz, who is chair of the anatomy and neurobiology department and a member of UC Irvine’s Epilepsy Research Center.
Epilepsy affects more than 2 million individuals of all ages in the U.S. alone and at least 50 million worldwide. It is characterized by the occurrence of spontaneous, unpredictable seizures, which can interfere with daily life, be dangerous, and lead to death of some brain cells. While much information is available about the abnormal communication of neuronal networks in epilepsy, the basic mechanisms, involving both genetic and acquired elements, are not fully understood.
The National Institutes of Health and the UC Irvine Medical Scientist Training Program supported the study.
About the University of California, Irvine: The University of California, Irvine is a top-ranked university dedicated to research, scholarship and community service. Founded in 1965, UCI is among the fastest-growing University of California campuses, with more than 27,000 undergraduate and graduate students and nearly 2,000 faculty members. The third-largest employer in dynamic Orange County, UCI contributes an annual economic impact of $3.6 billion. For more UCI news, visit www.today.uci.edu.
News Radio: UCI maintains on campus an ISDN line for conducting interviews with its faculty and experts. The use of this line is available free-of-charge to radio news programs/stations who wish to interview UCI faculty and experts. Use of the ISDN line is subject to availability and approval by the university.
Contact:
Tom Vasich
949-824-6455
tmvasich@uci.edu
UCI maintains an online directory of faculty available as experts to the media. To access, visit www.today.uci.edu/experts.
For UCI breaking news, visit www.zotwire.uci.edu.
Journal
Proceedings of the National Academy of Sciences