Migraine-associated protein triggers pain with gender specificity

Migraine is a common chronic neurovascular disorder and the second leading cause of disability. Migraine is mainly characterized by episodic moderate-to-severe, pulsatile headache. Most of the headaches are unilateral, usually lasting 4 to 72 hours, which may be accompanied by nausea and vomiting. Light, sound stimulation or daily activities can aggravate headaches, on the contrary, rest and quiet environment can relieve headaches.

Migraine attacks in children and adolescence, the peak incidence in young and middle-aged. It is more common in women, and the incidence of women is almost three times that of males. 

A new preclinical study led by the University of Texas at Dallas may help explain why migraine is three times more common among women than men. The online study, published in the journal Neuroscience, describes a protein associated with the development of migraine symptoms that causes a pain response in female rodents, but male ones were unaffected by the introduction of the protein into the meninges.

Previous studies on migraine have been most commonly referred to as CGRP (calcitonin gene-related peptide), but since the study model is only suitable for male animals, the problem of gender differences in neurobiology is ignored. And it has been not known where CGRP contributes to the condition of the body.

This study demonstrates for the first time that CGRP may behave differently in different genders. It also indicates that CGRP may have pain-related effects in the meninges, which has been questioned in previous literature.

CGRP has a prominent role in migraine. Scientists have been studying CGRP for more than 30 years. CGRP is widely distributed in the central, peripheral, and other systems, including the meninges. But CGRP itself is too large to pass through the blood-shield brain barrier of the central nervous system, so it can no longer move between the two.

The headache signal is emitted by neurons that innervate the meninges. According to all the symptoms and stages of migraine performance, this condition is thought to start from the brain.

The researchers injected small doses of CGRP into the outermost layer of the meninges of the experimental animals and observed that only females developed headache symptoms. They then injected CGRP into the paws of females and observed a similar pain response.

Experimental results suggested that women may be more sensitive to CGRP, not just the meninges. But whether other types of pain also have this response remains to be proven.

The causes of female migraine epidemics can be complex. But this study does prove that CGRP-based signaling in the meninges may lead to a predisposition to this disease in women, whereas male rodents are not affected by the introduction of CGRP in the meninges.

As CGRP gains more attention in migraine prevention research, the US Food and Drug Administration recently approved three therapeutic drugs that block proteins.

Although the role of CGRP in migraine has been identified, this does not mean that migraine is only associated with CGRP, but rather that CGRP may behave differently in women.