A new study has revealed a previously undiscovered pathway from the brain to peripheral nerves, which could help explain why migraines cause auras. An aura is a short duration of any of the sensory disturbances like lights, sounds, or sensations like tingling, and it is present in about a quarter of migraine patients.
Waves of abnormal activity in the brain called cortical spreading depression were discovered to stimulate pain-sensing nerves located outside the brain through chemical release in the cerebrospinal fluid. Until now, it was not clear how these chemicals got to the nerves in the first place. This was discovered in a study that appeared in Science and pointed at a path in the trigeminal ganglion, a group of neurons located in the brainstem.
CSF movement was monitored by scientists using genetically modified mice with neurons that lit up when in contact with calcium. They found that CSF, with pain mediators, goes to the trigeminal ganglion, where it stimulates pain-carrying sensory neurons. This relationship between the brain and peripheral nerves goes a long way in explaining the relationship between aura and migraine headaches.
Out of the 12 proteins that were identified to stimulate pain-sensitive nerves, only one protein is CGRP, and this is the only one that is targeted by migraine medications. These medications aid around fifty percent of migraine sufferers, which means that many patients have no adequate treatment. It can be concluded that the study results may point to new treatments by aiming at other molecules.
The next stage is to conduct similar studies in human beings or more human mimicking models with a view to enhancing the diagnosis and treatment of various headache disorders. This discovery opens the door to the further exploration of migraines and presents a new opportunity for treatments.
