Staying in balance after stroke

Strokes affect nearly a million Americans each year, but an already-approved drug used for epilepsy could dramatically reduce their debilitating impact.

New research shows one dose of the anti-epilepsy drug retigabine given hours after a mouse experienced a stroke preserved brain tissue and prevented the loss of balance and motor coordination.

In the study, both treated mice and untreated mice were placed on a balance beam after a stroke. The untreated mice showed a marked loss of coordination with repeated slips and falls, while treated mice had no difficulty with balance, ambulation or turning around on the beam.

“You couldn’t even tell they had a stroke,” said Mark S. Shapiro, Ph.D., professor of physiology. “They ran across the balance beam like gymnasts.”

Brain tissue of the treated mice showed significantly reduced damage to the tissue, compared to untreated mice. The protective effects of the medication were seen up to five days after the stroke, said Sonya Bierbower, Ph.D., postdoctoral fellow. The study was published in The Journal of Neuroscience.

Future studies will assess how long brain function can be protected after a stroke, whether injury-related seizures can be prevented and if strokes can be prevented in high-risk animal models.

A drug called tissue plasminogen activator commonly treats strokes by dissolving blood clots to restore blood flow, but there are significant limitations. It is most effective in the first hours after a stroke, but its later use may do more damage than good.

Drugs such as retigabine work on a completely different system. Instead of thinning blood, they preserve cells by putting a brake on their electrical activity, Dr. Shapiro said.

“It’s treating the first step in the sequence and stopping the more damaging secondary effects,” Dr. Bierbower added. “These agents directly affect the nerve cells themselves.”

Retigabine is approved by the Food and Drug Administration as an anticonvulsant, so physicians may use it off label in stroke patients. FDA approval for use as a stroke therapy will require a clinical trial to be conducted—something that a team of neurologists and neurosurgeons is already considering, Dr. Shapiro said.