Searching for Better Treatments for Epilepsy
In the U.S, epilepsy causes more deaths– about 50,000 annually – than breast cancer. While most epilepsy patients live long lives, sudden unexplained death in epilepsy (SUDEP) is the leading cause of premature death. A poorly understood disorder, SUDEP is thought to result from seizure complications that make it difficult to breathe, or that cause heart failure.
These disturbing trends are likely due, in part, to the fact that existing medications fail to adequately control seizures in one-third of epilepsy patients. Researchers worldwide are working to expand treatment options by investigating the fundamental differences in people for whom medications don’t work.
“We know that about two-thirds of all epilepsies are due to genetic mutations in a surprisingly large number of genes. The remaining one-third result from insults to the nervous system, be it an infection, traumatic brain injury, or something else,” said Karen Wilcox, Ph.D., professor of pharmacology at the University of Utah. “These complexities make it difficult to understand why some patients respond quite well to anticonvulsant drugs while others do not.”
All seizures arise from abnormal electrical activity in neurons that, like wildfire, can ignite their neuron neighbors, and spread across the brain. Symptoms – including convulsions, staring, and confusion - vary widely, depending on which parts of the brain are affected. Today’s anticonvulsant drugs work by affecting different types of neurons and their activities.
While it’s known that uncontrolled neural activity is at the core of seizures, new research is revealing that this isn’t the whole story. Advances in epilepsy research point to other phenomenon such as inflammation and disruptions in the blood-brain barrier as important factors in epilepsy. Wilcox has found that another cell type in the brain, called astrocytes, may also be to blame.
Astrocytes are a subtype of glial cells, or glia, which actually outnumber neurons. Glia, Greek for “glue”, were long disregarded as passive scaffolding upon which complex neural networks are built. Within the last twenty years, scientists have discovered that glia have many important, active roles such as regulating neural activity, providing neurons with nutrients, and repairing the nervous system after injury.
Wilcox has shown that in animal models, astrocytes are called to action after an insult to the brain, suggesting they may be active players in seizure development. She is now searching for ways to use this information to find new therapeutic targets for seizure control.
“We need to be looking to other areas for therapy development,” said Wilcox. “Our lab is trying to make inroads into how astrocytes and glia contribute to network excitability. We think that could provide really good novel targets for therapies and also may provide clues to how epileptogenesis may occur.”
The hope is that new therapies that target astrocytes, or other non-neuronal targets, will provide relief for patients whose seizures don’t respond to currently available medications.
Epilepsy Fast Facts*
- An epilepsy diagnosis is given after a person has had two or more seizures.
- There is an 80% chance that a person who has had two seizures will have more.
- One in 26 Americans will develop epilepsy in their lifetime.
- There are many risk factors for epilepsy, including traumatic brain injury, brain infection, brain tumors, stroke, illegal drug use, and genetic factors.
- Medications successfully control seizures in two-thirds of people with epilepsy.
- For patients whose seizures are not adequately controlled by drugs, possible alternatives include surgery and therapeutic devices such as vagus nerve stimulation and responsive neurostimulation.
*Sources: Epilepsy Foundation, CURE
- To make an appointment with a University of Utah Health Care neurologist, call the Clinical Neurosciences Center at 801-585-7575.
- For more information about epilepsy and epilepsy research, visit the following websites: Epilepsy Foundation, Citizens United for Research in Epilepsy (CURE), and the Center for Disease Control.
- Listen to an interview with Dr. Karen Wilcox on The Scope Radio to learn more about her research.
About the author:
Julie Kiefer, Ph.D., is a research communications specialist with the Office of Public Affairscomments powered by Disqus