May 6, 2013
Brain Cell Transplant Cures Severe Form Of Epilepsy In Mouse Model
redOrbit Staff & Wire Reports - Your Universe Online
Scientists from the University of California - San Francisco (UCSF) have effectively cured epilepsy in mice by transplanting brain cells into the rodents´ hippocampus — research that they hope could one day be applied to help treat severe forms of the condition in humans.
Dr. Scott C. Baraban, who holds the William K. Bowes Jr. Endowed Chair in Neuroscience Research at UCSF, and colleagues took medial ganglionic eminence (MGE) cells, which inhibit signaling in overactive nerve circuits, and transplanted them in the area of the brain associated with seizures.
While previous research focusing on different cell types proved unsuccessful, Baraban´s team was able to control the seizures in epileptic mice following the transplantation. The results of their work, which is reportedly the first ever successful attempt to stop seizures in mouse models of adult human epilepsy, were published Sunday in the online edition of the journal Nature Neuroscience.
“Our results are an encouraging step toward using inhibitory neurons for cell transplantation in adults with severe forms of epilepsy,” Baraban, whose work was funded by the National Institutes of Health (NIH) and by the California Institute of Regenerative Medicine, said in a statement. “This procedure offers the possibility of controlling seizures and rescuing cognitive deficits in these patients.”
According to the researchers, epileptic seizures often lead to severe muscle contractions and a possible loss of consciousness. As a result, the patient can lose control of his or her body, falling and potentially becoming seriously injured. These seizures occur when too many excitatory nerves in the brain fire at the same time.
However, the UCSF researchers report that the inhibitory cells they implanted into the mice “quenched this synchronous, nerve-signaling firestorm, eliminating seizures in half of the treated mice and dramatically reducing the number of spontaneous seizures in the rest.”
“These cells migrate widely and integrate into the adult brain as new inhibitory neurons,” Baraban explained. “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.”
The model that the UCSF team worked on was designed to resemble an especially severe form of human epilepsy known as mesial temporal lobe epilepsy. Mesial temporal lobe epilepsy is typically resistant to medication, and in this condition, the seizures are believed to originate in the hippocampus.
While the transplantation into this region of the brain proved successful, transplants into the amygdala — a region of the brain involved in memory and emotion — was unable to end seizure activity in this same mouse model, Baraban´s team said. Furthermore, in addition to reducing seizures, the mice treated in this way became less agitated and less hyperactive, and also performed better in water-maze tests, they added.