Jan. 2 (UPI) -- Researchers developed two methods of treatment for seizures in the brains of children with Dravet syndrome after finding the "exact spot" in the brain causing them, according to a new report.
Findings published Wednesday in the journal Cell Reports keyed in on the region of the brain in lab mice that causes "silent seizures," or seizures that don't bring on physical convulsions, with the hopes of stopping the condition.
"We were able to pinpoint the exact spot in the brain that causes the seizures," Jeanne Paz, an assistant investigator at the Gladstone Institutes and the study senior author, said in a news release. "This discovery allowed us to develop two new strategies to prevent these non-convulsive seizures in mice simulating Dravet syndrome."
In close to 80 percent of patients, Dravet syndrome can cause a genetic mutation that leads to both developmental delays and fatal seizures.
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The Dravets Syndrome Foundation estimates that the mortality rate for people with the condition is between 15 and 20 percent.
Convulsive seizures occur in the brain's cerebral cortex when the excitatory neurons malfunction and fire off too wildly. They also happen when the inhibitory cell, meant to regulate the excitatory neurons, don't work properly either.
That's why, traditionally, scientists attempt to develop treatments to repair the excitatory and inhibitory neurons.
But children with Dravet syndrome don't convulse like kids who experience other types of seizures. Rather, they display cognitive malfunctions, sleep problems and autistic tendencies. So Paz and her team decided to research the thalamus area of the brain responsible for attention, cognition and sleep.
"All of these elements are altered in patients with Dravet syndrome in a way that is unlikely to be caused only by changes in the cerebral cortex," said Paz, an assistant professor of neurology at University of California San Francisco. "We wanted to see what happens in this brain region and how its cells might be altered in the context of this syndrome."
Paz and her researchers used an electroencephalography, or EEG, to detect silent seizures, which cause a child to lose consciousness without falling down. The silent seizures just leave the child staring unattentively during an attack.
"Imagine you have several 20-second blanks while I'm talking -- you'll get a sense of what I'm saying, but you won't understand all of it," explained Cilio. "Although they may not be as dramatic as convulsions, these interruptions can happen regularly throughout the day, so they really impair learning."
So, after identifying the area in the mice thalamus where the silent seizures lived, they treated it with a method called optogenetics -- which includes controlling neurons with light -- that controls the neurons responsible for the seizures.
Since optogenetics can't be used on humans yet, Paz instead used a drug called EBIO1, which decreased firing of inhibitory cells.
"When I presented my findings recently at the American Epilepsy Society, some physicians expressed keen interest in testing this FDA-approved drug in the clinic," Paz said. "Hopefully, this will be life-changing for these children."
