When the brain gets injured, star-shaped brain cells called astrocytes come to the rescue. In the case of glioma – the most common type of primary brain tumor – this protective action comes at a price. A new study published in Neurochemistry International reveals that gliomas alter astrocyte function, which normally prevents the brain from being flooded with excess excitatory chemicals. This could contribute to the seizures experienced by many brain cancer patients.
Toxic levels of glutamate emitted from the tumor, exacerbated by the astrocytes dysfunctional state, destroy healthy neurons. Previous studies led by Sontheimer showed that the fluid suspended between brain cells reaches harmful levels of excitability – enough to spark a seizure. After the first seizure, the circuits involved are preferentially strengthened, making future episodes even more likely.