Exactly what toxic factor activates the Bax pathway has not been determined, Dr. Przedborski said.
But if the cell culture experiments reflect what's actually happening in people with ALS, he said, "blocking the toxic factor released by astrocytes as early as possible could become an effective neuroprotective strategy against this disease."
He added that the findings may lead to earlier diagnosis. "Currently, we diagnose ALS at a point when a large number of motor neurons are already gone," he said.
But knowing what toxic factors are being released would open the possibility of being able "to screen people for elevated levels of these proteins and intervene in a tangible way perhaps even before a person displays any clinical sign of ALS," he said.