The Use of Stem Cell Therapy in Epilepsy

Listen as Basic Science Editor Sloka Iyengar PhD talks about the use of stem cell therapy in epilepsy.

Anti-epileptic drugs or seizure medications work well for 2 out of 3 people with epilepsy, but we need more effective therapies for people who still have seizures or side effects of medicines.

This is where stem cell therapy may someday become an alternative. For epilepsy, stem cell research is still in its infancy and has been carried out in experimental animals. There are two main ways in which stem cell therapy can be used in epilepsy. Experiments exploring the use of stem cells in epilepsy have been pioneered by Dr. Scott Baraban at University of California, San Francisco (UCSF).

1. Transplantation of interneurons
   • The brain has neurons that can excite other cells and others that inhibit or stop action of cells. Normally, there is enough balance between these cells to help us function normally (i.e., think, remember, etc). During a seizure, the balance between exciting and inhibiting cells is off. Ways to decrease excitation or increase inhibition may be useful in epilepsy. Many current seizure medications focus on changing ways cells inhibit brain function.
   • A similar approach has been tested with stem cells. Specific groups of inhibitory neurons (also called interneurons) are formed from a specific area of the brain (called the medial ganglionic eminences). When scientists took these neurons and transplanted them into the brains of animals that had been treated to have seizures, they found that these cells were able to work and increase inhibition. This reduced seizures.
   • These results are promising, but more work needs to be done before they can be tested in people with epilepsy. Other disorders like Alzheimer’s disease and autism may be associated with seizures. An interesting question is whether stem cell therapy might help in those conditions as well.
   • Other important questions:
     • How long would the effect of stem cells last?
     • What side effects may happen?
     • Could other problems that may occur in people with epilepsy (such as depression or anxiety) be helped by stem cells?
2. Induced pluripotent stem cells (iPSCs)
   • Some epilepsies are caused because of a genetic mutation or change in neurons. For example, Dravet syndrome is a devastating form of childhood epilepsy caused by a mutation in a specific sodium channel.
   • Scientists have found a way to take the connective (skin) tissue from people with Dravet syndrome and program them to become any type of cell in the body. These new cell types are called pluripotent stem cells. These new cells can be made into neurons.
   • In a research laboratory, these neurons can be used to study the effects of specific drugs and give scientists a better understanding of Dravet syndrome.

Although much more research needs to be done, stem cell therapy is an attractive and promising treatment for epilepsy.