MONTREAL, May 12 (UPI) -- Canadian researchers say they've discovered cells that support neuron survival also play a role in the death of neurons located in the eye.
Researchers from the University of Montreal and McGill University said their findings might lead to improved therapies for some neurological disorders, including glaucoma and retinal artery occlusion.
The scientists said in many neurodegenerative diseases, a main factor that kills neurons is excessive levels of the neurotransmitter glutamate. Diseases that occur as a result of high glutamate levels include hypoxic-ischemic stroke, seizures, dementia and neurodegeneration. For years, the main explanation for the toxic effects of glutamate was that it overexcites neuronal cells via activation of glutamate receptors, thereby killing them.
"The most interesting aspect of our study and the reason we are so excited is that the pathway leading to glutamate-induced nerve cell death involves … glial cells," Adriana Di Polo, a University of Montreal neuroscientist, said. "Through careful experimentation we now know that glutamate activates signaling pathways in glial cells that then lead to neuronal death."
Glial cells are the most abundant cell type in the nervous system and are thought of as providing support, nutrients and an optimal environment. However, the scientists said their study indicates glial cells also have a more sinister side, allowing them to induce or exacerbate neuronal death in pathological conditions.
The study is reported in The Journal of Neuroscience.
