Study identifies the origin of migraines

A team of scientists described for the first time how the Shockwave of discomfort and fluid flow in the brain trigger migraines and identified new proteins that could be responsible for this disorder and therefore be the basis for future drugs.

“We have described the interaction between the central and peripheral nervous systems caused by the increase in the concentrations of proteins released in the brain during an episode of generalized depolarization, the phenomenon that causes the aura associated with migraines,” he explains. Maiken Nedergaard, from the University of Rochester (New York) and lead author of the study.

These findings, published in the journal “Science” and reported by the EFE agency, “provide us with a large number of new targets for suppressing sensory nerve activation to prevent and treat migraines and strengthen existing therapies,” says the scientist.

It is estimated that One in 10 people suffers from migrainesthat in a quarter of these cases the Headache is preceded by a sensory disturbance (aura) which can include flashes of light, blind spots, double vision, and tingling or numbness in the extremities, symptoms that appear five to 60 minutes before the headache.

Although migraine auras arise in the brain, the organ itself cannot sense pain. Instead, these signals must be transmitted from the central nervous system—the brain and spinal cord—to the peripheral nervous system, the communication network that transmits information from the brain to the rest of the bodyalso about touch and pain.

The great mystery has been knowing how the communication process between the brain and the peripheral sensory nerves works in migraines.

In the new study, Nedergaard’s team, together with researchers from the University of Copenhagen, were able to describe what fluid flow in the brain looks like and how it behaves.

To do this, the team built detailed models of how cerebrospinal fluid moves (LCR) in the brain and its role in the transport of proteins, neurotransmitters and other chemical substances.

The most accepted theory It was thought that nerve endings that rest on the outer surface of the membranes surrounding the brain were responsible for the headaches that follow the aura, but the new study, carried out in mice, described a different route and identified proteins —many of which are possible new drug targets— which may be responsible for activating the nerves and causing pain.

As the depolarization wave propagates, Neurons release into the cerebrospinal fluid (CSF) ora series of inflammatory and other proteins.

In experiments with mice, the team showed that CSF transports these proteins to the trigeminal gangliona large bundle of nerves located in the bskull ase that supplies sensory information to the head and face.

This ganglion, like the rest of the peripheral nervous system, was thought to lie outside the blood-brain barrier, which strictly controls which molecules enter and leave the brain, but the team identified a previously unknown loophole that allows CSF to flow directly into the trigeminal ganglion and exposes sensory nerves to the cocktail of proteins released by the brain.

Molecules behind migraines are being studied

By analyzing the molecules, the researchers identified twelve proteins called ligands that bind to sensory nerve receptors in the trigeminal ganglion, potentially triggering activation of these cells.

“We have identified a new signaling pathway and several molecules that activate sensory nerves in the peripheral nervous system. Among the molecules identified are those already associated with migraines, but we did not know exactly how and where the migraine-inducing action occurred,” explains Dr. Martin Kaag Rasmussenfrom the University of Copenhagen and first author of the study.

“Defining the role of these newly identified ligand-receptor pairs may help to discover new drug targets, which could benefit the large proportion of patients who do not respond to available therapies.”

The team also observed that the transport of proteins released on one side of the brain It mainly reaches the nerves of the trigeminal ganglion on the same side, which could explain why — in most migraines — the pain occurs only on one side of the head.