Targeting CGRP pathways and aura: A peripheral site with a central effect

Migraine with and without aura-two distinct entities? A narrative review

Migraine is a primary headache disorder, with a prevalence estimated at approximately 15% globally. According to the International Classification of Headache Disorders, 3rd edition (ICHD3), there are three significant types of migraine: migraine without aura (MO), migraine with aura (MA), and chronic migraine (CM), the former being the most common. Migraine diagnosis is based on official criteria specific to each type. Although a lot is already known about the origin of migraine aura, its pathophysiology is still an object of research.Long-term discussions have been held about MO and MA, with some evidence for the same underlying pathogenesis of both and other arguments against it. In this narrative review, we decided to analyse multiple factors from the perspective of similarities and differences between these two types of migraine. The aim was to understand better the bases underlying both types of migraine.Aspects such as genetics, molecular bases, relation with hormones, epidemiological and clinical features, neuroimaging, neurophysiology, treatment response, and migraine complications are covered to find similarities and differences between MO and MA. Although epidemiology shares similarities for both types, there are slight alterations in sex and age distribution. Genetics and pathogenesis showed some crucial differences. Conditions, such as vestibular symptoms and depression, were found to correlate similarly with both types of migraine. For some features, including increased cardiovascular risk, the tendency appeared to be the same; however, migraine types differ in the strength of correlation. Finally, in cases such as hormones, the influence has shown opposite directions. Therefore, although migraine with and without aura are considered two types of the same disease, more research should focus on their differences, thus finally enabling better specific treatment options for both types of migraine.

Migraine headache and aura induced by hypoxia

Migraine, a common neurological disorder, impacts over a billion individuals globally. Its complex aetiology involves various signalling cascades. Hypoxia causes headaches such as high-altitude headache and acute mountain sickness which share phenotypical similarities with migraine. Epidemiological data indicate an increased prevalence of migraine with and without aura in high-altitude populations. Experimental studies have further shown that hypoxia can induce migraine attacks. This review summarizes evidence linking hypoxia to migraine, delves into potential pathophysiological mechanisms and highlights research gaps.

Voltage-gated Calcium Channels as Potential Therapeutic Targets in Migraine

Migraine is a complex and highly incapacitating neurological disorder that affects around 15% of the general population with greater incidence in women, often at the most productive age of life. Migraine physiopathology is still not fully understood, but it involves multiple mediators and events in the trigeminovascular system and the central nervous system. The identification of calcitonin gene-related peptide as a key mediator in migraine physiopathology has led to the development of effective and highly selective antimigraine therapies. However, this treatment is neither accessible nor effective for all migraine sufferers. Thus, a better understanding of migraine mechanisms and the identification of potential targets are still clearly warranted. Voltage-gated calcium channels (VGCCs) are widely distributed in the trigeminovascular system, and there is accumulating evidence of their contribution to the mechanisms associated with headache pain. Several drugs used in migraine abortive or prophylactic treatment target VGCCs, which probably contributes to their analgesic effect. This review aims to summarize the current evidence of VGGC contribution to migraine physiopathology and to discuss how current pharmacological options for migraine treatment interfere with VGGC function. PERSPECTIVE: Calcitonin gene-related peptide (CGRP) represents a major migraine mediator, but few studies have investigated the relationship between CGRP and VGCCs. CGRP release is calcium channel-dependent and VGGCs are key players in familial migraine. Further studies are needed to determine whether VGCCs are suitable molecular targets for treating migraine.

Can calcitonin gene-related peptide monoclonal antibodies ameliorate writer's cramp and migraine?

Recently, calcitonin gene-related peptide (CGRP) monoclonal antibodies (mAbs) have become available as a prophylactic treatment for migraine and have shown high efficacy and safety in clinical practice. CGRP mAbs have been reported to be effective not only for migraine but also for other comorbidities, such as psychiatric complications in patients with migraine. However, there are no reports examining the effect of CGRP mAbs on dystonia. We treated a patient with comorbid migraine and focal task-specific dystonia (writer's cramp) with a CGRP mAb (erenumab) because of an increase in monthly migraine days despite the addition of migraine prophylaxis. In this patient, erenumab treatment for 3 months led to improvements in symptoms of both focal dystonia and migraine, suggesting a role for CGRP in the pathophysiology of both conditions.