Harald Sontheimer and Stefanie Robel, both scientists at the Virginia Tech Carilion Research Institute, published a review paper in Nature Neuroscience titled, “Glia as drivers of abnormal neuronal activity.” The paper summarizes recent research that points to a surprising finding about the disease process in brain cells.

Glia cells are the most abundant cell in the brain, outnumbering even neurons. Astrocytes are a specific type of glia cell that help regulate neuronal activity.

“Astrogliosis refers to the morphological and biochemical changes of astrocytes occurring in association with injury or disease,” wrote Sontheimer, who is also director of the Virginia Tech Carilion Research Institute’s Glial Biology in Health, Disease, and Cancer Center. “In the healthy brain, astrocytes are important for homeostasis.”

When the brain becomes severely injured or diseased, however, the astrocytes appear to gradually revert to an immature stage, incapable of performing their most basic of tasks. They appear useless, and possibly incapable of playing a role in the disease process.

Based on recent research, Sontheimer and Robel suggest that reactive astrocytes may actually aid in furthering disease in the brain, specifically in cases of epilepsy.

The research points to the interaction between reactive astrocytes and the receptors of the neurotransmitter GABA. Known as an inhibitory neurotransmitter, GABA helps reverse overexcitement in the brain to maintain equilibrium. Sontheimer and Robel suggest that recent studies indicate the reactive astrocytes may impair the GABA receptors in such a way that the inhibitory action is lost. Without a way for the brain to counteract excitatory behavior, seizures and epileptic episodes may occur.