New treatment options for epileptics
A University of Adelaide scientist and his US colleagues have made a significant breakthrough in the causes of epilepsy, which affects about 50 million people worldwide.
Postdoctoral researcher Dr Mark Hutchinson from the Discipline of Pharmacology and neuroscientists from the University of Colorado in Boulder have revealed for the first time the role that the brain's immune cells play in triggering epileptic seizures.
Their findings, recently published in the international neurology journal Brain, demonstrate that while neurons are responsible for some epileptic attacks, the brain's immune cells, known as glia, also influence neuronal electrical activity.
Dr Hutchinson said the discovery could lead to more effective treatment options for millions of epilepsy sufferers around the world.
"There are a whole host of people who are getting treated for epilepsy using drugs that are targeting the neurons, when perhaps the original cause for their seizures could be the brain's immune system," he said.
The study, led by the University of Colorado, was prompted in part by the expected massive increase in epilepsy among US soldiers who have suffered traumatic brain injuries in Iraq and Afghanistan as a result of roadside bomb blasts.
Dr Hutchinson said neuronal models of epilepsy may not hold true for seizures triggered by traumatic brain injuries.
"Some people have a genetic predisposition to epilepsy, while other seizures occur in the aftermath of brain infections such as meningitis and HIV-related conditions. Then there are seizures associated with some drugs. All of them present with a spiking of neuronal activity but the underlying causes can be due to the brain's immune cells," Dr Hutchinson said.
"With brain wounds, tumours, blockages and infection, glial cells accumulate in the damaged region of the brain to help repair and reconstruct cells. However, they can also trigger epileptic seizures."
Glia account for up to 90% of the cells in the brain, with the remainder made up of nerve cells.
"Initially we thought that glia just provided structural support for the brain, holding the nerves in the right place and feeding them, but it appears they are responsible for a whole lot more, including neuropathic pain and drug addiction," Dr Hutchinson said.
The University of Colorado has applied for funding to trial various drugs that block the brain immune cells from activating.
The research team was led by Professor Dan Barth and included Professor Linda Watkins, Professor Steven Maier, Alexis Northcutt and Krista Rodgers, all from the University of Colorado, as well as Dr Mark Hutchinson.
Dr Hutchinson graduated with a Bachelor of Science degree with First Class Honours from the University of Adelaide in 1999, majoring in microbiology, immunology and pharmacology.
He won the Australian Fresh Science Award in 2004 for his research into the links between the brain's immune system, pain tolerance and morphine addiction.
The following year Dr Hutchinson was awarded an American-Australian Association Fellowship to pursue studies in the United States. He spent three years working at the University of Colorado in the Center for Neuroscience before returning to the University of Adelaide in 2008 to continue his research.
Story by Candy Gibson