Epilepsy in children can be very damaging. Children who suffer from a type of epilepsy called Dravet syndrome can begin to have convulsive seizures as early as three months of age. As the children get older, they will have another type of seizure appear. The new seizures do not cause convulsions when they occur, but cause problems with the consciousness of the child. In some cases, this can occur more than 50 times in a single day. Since these seizures do not have convulsions, they are often more difficult to detect and treat because they go unnoticed by both the parents and the doctors.
New Study Brings Hope
A study published in the journal Cell Reports, took a look at silent seizures in a mouse model for Dravet syndrome. Researchers characterized these seizures and located an area of the brain that could be targeted as a means to stop the seizures. According to the senior author of the study, Jeanne Paz, PhD, and an assistant investigator at the Gladstone Institutes, they were able to pinpoint the spot in the brain that causes these seizures. By discovering the specific location, researchers developed and implemented two new strategies as a means to help prevent the non-convulsive seizures in the mice who were simulated having Dravet syndrome.
While this research was done in mice, a collaboration with Maria Roberta Cilio, MD, PhD, a pediatric epileptologist working at UC San Francisco, helped Paz to confirm that the findings are likely to be “relevant to the human condition.”
What Strategies Could Help Reduce Seizures?
The seizures often go unnoticed, so Paz has been referring to them as "silent seizures." However, they're usually called atypical absence seizures. Typically, when a child is experiencing one of the seizures, they show very few outward signs. The most common sign is that they appear absent-minded, for example starring into space blankly. To an outsider, it might seem as though they are not paying attention.
As mentioned earlier, these types of seizures can occur 50 or more times a day. If they occur in spans of 10 to 30 seconds, as they often do, this means the children could be missing out on a lot over the course of the day. While it does not have the often frightening convulsions accompanying them, these types of seizures can be no less detrimental to the child.
The first new way that Paz and her team discovered to help stop nonconvulsive seizures was through the use of optogenetics. This helps make it possible to control the activity of neurons using a laser light. The researchers were able to develop methods that would allow them to detect seizures. Once the seizures were detected, they "quickly changed the activity of neurons in the thalamus to stop the seizures."
This type of procedure cannot be used in humans at this time. The team looked for another option that could provide a similar result. They found a drug named EBI01 that was capable of reducing the “firing of inhibitory cells in the thalamus.” The mice treated using this drug had their seizures reduced substantially and in some cases, the seizures stopped.
This drug is already FDA approved, although it has never been used for epilepsy before. There were no side effects reported with the drug during clinical trials for movement disorders. This means the drug could be available for patients far more quickly than the introduction of optogenetics. The information gleaned from the study could help to change the lives of children suffering from Dravet syndrome for the better.