A team of researchers has now found a way to cure epilepsy in mice using cells called the medial ganglionic eminence (MGE) cells that stop overactive nerve signals from reaching the hippocampus. The therapy might one day be useful in treating people with epilepsy.

Epilepsy is a brain disorder in which the affected person has several seizures over time. Approximately 2 million people living in the U.S. have epilepsy, with another 140,000 developing the disorder each year. Epilepsy costs about $15 billion to the U.S. economy, CDC says.

The study was conducted by researchers from University of California, San Francisco. In this study, the transplanted cells inhibited overactive signals in the key part of the brain that's associated with learning and memory.

In the present study, researchers found that the transplanted cells inhibited excessive nerve signaling in the brain, reducing the likelihood of a seizure in the treated mice.

The loss of inhibitory nerve cells plays an important role in the progression of many types of epilepsy. The MGE cells form very early at the embryo stage and can give rise to mature inhibitory nerve cells called interneurons. In the present study, the cells that the team transplanted in mice took the place of these "lost" interneurons. These cells then integrated with normal brain circuitry.

"These cells migrate widely and integrate into the adult brain as new inhibitory neurons. This is the first report in a mouse model of adult epilepsy in which mice that already were having seizures stopped having seizures after treatment," said Scott C. Baraban, PhD, from UCSF and the lead author of the study, in a news release.

The study is published in the journal Nature Neuroscience.

Also, researchers have found a way to produce human MGE-like cells in a lab setting. These cells could also inhibit nerve signaling. This was in another study by the researchers, published in the journal Cell Stem Cell.

"Our results are an encouraging step toward using inhibitory neurons for cell transplantation in adults with severe forms of epilepsy. This procedure offers the possibility of controlling seizures and rescuing cognitive deficits in these patients," said Baraban.