Epileptic seizures strike when neurons [nerve cells] fire uncontrollably, but it’s not been clear what sparks this electrical storm. Most research has focused on neurons but scientists have now discovered that another type of brain cell called neuroglia or glial cells may play a key role by provoking neuron hyperactivity. Fruit flies with a mutation in a gene called zydeco – here shown switched on (purple) in glial cells (green) in non-mutated flies – suffer seizures when exposed to high temperatures. It turns out that zydeco helps to control calcium levels in the cells. In flies with the mutation calcium accumulates, which heat stress may further exacerbate, causing an overload in the glial cells that triggers seizure by overexciting neighboring neurons. The results suggest that preventing calcium build-up in human glial cells could reduce the chances of epilepsy patients suffering seizures in response to extreme heat or cold.
Written by Daniel Cossins
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