Gender aspects of CGRP in migraine

Headache in Women

PURPOSE OF REVIEW

Women are greatly overrepresented among patients seeking treatment for symptoms of headache pain in general and migraine in particular. Understanding the presentation of headache in women in relation to hormonal changes both during the menstrual cycle and throughout the life span is essential for appropriate diagnosis and treatment.

RECENT FINDINGS

Although perimenstrual migraine attacks are generally without aura, the diagnosis of migraine with aura has been added to the headache classification for menstrual migraine to account for women with the diagnosis of migraine with aura who experience menstrual migraine attacks. Emerging knowledge regarding the differences between menstrual and nonmenstrual attacks, the variability of attack triggering within and between women, and the response of women with menstrually related migraine to new migraine drug classes is contributing to better understanding and more effective treatment of these particularly burdensome and refractory attacks. Given the burden of migraine, almost one-fourth of women with migraine avoid or delay pregnancy. Women who experience migraine during pregnancy are more likely to have a hypertensive disorder and stroke during pregnancy and/or delivery and the postpartum period. Treatment of headache in general and migraine in particular in pregnancy is challenging because of fetal and maternal risks; however, a 2021 systematic review suggests that triptans and low-dose aspirin may not be associated with fetal/child adverse effects and could be more strongly considered for headache treatment in pregnancy.

SUMMARY

Headache in general and migraine in particular are extraordinarily common in women of reproductive age and fluctuate with hormonal changes and phases of life. Improved knowledge of the epidemiology, pathophysiology, and response to treatment of perimenstrual attacks is essential for more effective response to this most burdensome headache type. Treatment of headache in pregnancy remains challenging.

Clinical significance of serum sex hormones in postmenopausal women with vestibular migraine: potential role of estradiol

OBJECTIVE

This study aimed to investigate the role of sex hormones in postmenopausal women with vestibular migraine.

METHODS

This observational study included 242 female patients with vestibular migraine who were postmenopausal during April 2017 to December 2019. Serum levels of sex hormones, including estradiol, progesterone, testosterone, follicle-stimulating hormone, luteinizing hormone, and prolactin, were determined by radioimmunoassay. The duration and frequency (every month) of onset of vestibular migraine were recorded. The degree of vestibular migraine was measured by the visual analogue scale.

RESULTS

Serum levels of estradiol, progesterone, and testosterone were significantly lower, while serum prolactin levels were significantly higher in postmenopausal patients with vestibular migraine compared with healthy controls. Serum estradiol levels were negatively correlated with the duration, frequency, and severity of onset of vestibular migraine. Patients with higher serum estradiol levels showed a longer disease-free survival time.

CONCLUSION

Sex hormones are correlated with vestibular migraine in postmenopausal women. Additionally, estradiol levels are correlated with the duration, frequency, and severity of onset of vestibular migraine, as well as the disease-free survival time.

Independent association of palpitation with vasomotor symptoms and anxiety in middle-aged women

OBJECTIVE

Palpitation, or the sensation of rapid or irregular heartbeats, is common in menopausal women; however, the precise underlying mechanisms are unknown. We aimed to investigate factors associated with palpitation in middle-aged women.

METHODS

Medical records of 394 women aged 40 to 59 years (108 premenopausal, 85 perimenopausal, and 201 postmenopausal) were analyzed cross-sectionally. Palpitation severity was estimated based on responses to the Menopausal Symptom Scale. Effects of background characteristics, including age, menopausal status, body composition, cardiovascular parameters, basal metabolism, physical fitness, lifestyle factors, vasomotor, and psychological symptoms on palpitation were assessed using multivariate logistic regression analysis. The association between autonomic nervous system activity and palpitation was also analyzed in 198 participants.

RESULTS

Prevalence of palpitation by severity was as follows: none, 26.4%; mild, 32.7%; moderate, 29.4%; severe, 11.4%. In univariate analyses, the more severely the women were affected by palpitation, 1) the higher their systolic blood pressure, 2) the less exercise they performed, 3) the lower they scored in the sit-and-reach test, 4) the higher their vasomotor symptoms score in the Menopausal Health Related-Quality of Life questionnaire, and 5) the higher their Hospital Anxiety and Depression Scale. Multiple logistic regression analysis revealed that moderate to severe palpitation was independently associated with the vasomotor symptom score (adjusted odds ratio [95% confidence interval]: 1.18 [1.07-1.31]) and Hospital Anxiety and Depression Scale anxiety subscale score (1.19 [1.12-1.27]).

CONCLUSIONS

Rapid or irregular heartbeats are highly prevalent in middle-aged women. It is not associated with age, menopausal status, heart rate, arrhythmia, autonomic nervous system activity, caffeine, or alcohol consumption, but with vasomotor symptoms and anxiety.

Acute and Preventive Management of Migraine during Menstruation and Menopause

Migraine course is influenced by female reproductive milestones, including menstruation and perimenopause; menstrual migraine (MM) represents a distinct clinical entity. Increased susceptibility to migraine during menstruation and in perimenopause is probably due to fluctuations in estrogen levels. The present review provides suggestions for the treatment of MM and perimenopausal migraine. MM is characterized by long, severe, and poorly treatable headaches, for which the use of long-acting triptans and/or combined treatment with triptans and common analgesics is advisable. Short-term prophylaxis with triptans and/or estrogen treatment is another viable option in women with regular menstrual cycles or treated with combined hormonal contraceptives; conventional prevention may also be considered depending on the attack-related disability and the presence of attacks unrelated to menstruation. In women with perimenopausal migraine, hormonal treatments should aim at avoiding estrogen fluctuations. Future research on migraine treatments will benefit from the ascertainment of the interplay between female sex hormones and the mechanisms of migraine pathogenesis, including the calcitonin gene-related peptide pathway.

Gender-related differences in migraine

Migraine is considered mostly a woman’s complaint, even if it affects also men. Epidemiological data show a higher incidence of the disease in women, starting from puberty throughout life. The sex-related differences of migraine hold clinical relevance too. The frequency, duration, and disability of attacks tend to be higher in women. Because of this, probably, they also consult specialists more frequently and take more prescription drugs than men. Different mechanisms have been evaluated to explain these differences. Hormonal milieu and its modulation of neuronal and vascular reactivity is probably one of the most important aspects. Estrogens and progesterone regulate a host of biological functions through two mechanisms: nongenomic and genomic. They influence several neuromediators and neurotransmitters, and they may cause functional and structural differences in several brain regions, involved in migraine pathogenesis. In addition to their central action, sex hormones exert rapid modulation of vascular tone. The resulting specific sex phenotype should be considered during clinical management and experimental studies.

Effects of the Menstrual Cycle on Neurological Disorders

PURPOSE OF REVIEW

The menstrual cycle involves recurrent fluctuations in hormone levels and temperature via neuroendocrine feedback loops. This paper reviews the impact of the menstrual cycle on several common neurological conditions, including migraine, seizures, multiple sclerosis, stroke, and Parkinson's disease.

RECENT FINDINGS

The ovarian steroid hormones, estrogen and progesterone, have protean effects on central nervous system functioning that can impact the likelihood, severity, and presentation of many neurological diseases. Hormonal therapies have been explored as a potential treatment for many neurological diseases with varying degrees of evidence and success. Neurological conditions also impact women's reproductive health, and the cessation of ovarian function with menopause may also alter the course of neurological diseases. Medication selection must consider hormonal effects on metabolism and the potential for adverse drug reactions related to menstruation, fertility, and pregnancy outcomes. Novel medications with selective affinity for hormonal receptors are desirable. Neurologists and gynecologists must collaborate to provide optimal care for women with neurological disorders.

Plasma calcitonin gene-related peptide (CGRP) in migraine and endometriosis during the menstrual cycle

OBJECTIVE

Migraine, endometriosis, and the comorbidity of both are frequent pain disorders of special relevance for women. The neuropeptide calcitonin gene-related peptide (CGRP) is critically involved in migraine, and circumstantial evidence suggests a role in endometriosis. We assessed CGRP levels at different times of menstrual cycle in four groups: healthy women, women with migraine or endometriosis and with the comorbidity of both.

METHODS

Women with episodic migraine and women with a histologically confirmed endometriosis were recruited from specialized centers. For CGRP determination with a commercial enzyme immunoassay kit, cubital vein blood samples were collected on menstrual cycle day 2 ± 2 (during menstruation) and on day 15 ± 2 (periovulatory period). The primary endpoint of the study was the absolute difference of CGRP plasma levels between the menstrual and the periovulatory phase of all study groups. Groups were compared using nonparametric test procedures.

RESULTS

A total of 124 women were included in the study. The change of CGRP plasma levels between menstruation and the periovulatory period was different between groups (p = 0.007). Women with comorbid migraine and endometriosis showed an increase of CGRP in the menstrual phase of +6.32 (interquartile range, IQR -3.64-13.60) compared to the periovulatory time, while healthy controls had a decrease of -10.14 (-22.54-0.91, p = 0.004). CGRP levels were different in the periovulatory phase among groups (p = 0.008), with highest values in healthy controls.

INTERPRETATION

CGRP levels change significantly during the menstrual cycle. Different patterns in women with the comorbidity point to a deviant regulation of CGRP release.

Lasmiditan inhibits calcitonin gene-related peptide release in the rodent trigeminovascular system

Lasmiditan, an antimigraine drug with selective 5-HT_1F receptor affinity, prejunctionally inhibits calcitonin gene-related peptide release in peripheral and central trigeminal nerve terminals of rodents.

Migraine headache pathophysiology involves trigeminovascular system activation, calcitonin gene-related peptide (CGRP) release, and dysfunctional nociceptive transmission. Triptans are 5-HT_1B/1D/(1F) receptor agonists that prejunctionally inhibit trigeminal CGRP release, but their vasoconstrictor properties limit their use in migraine patients with cardiovascular disease. By contrast, lasmiditan is a novel antimigraine and selective 5-HT_1F receptor agonist devoid of vasoconstrictor properties. On this basis, this study has investigated the modulation of trigeminal CGRP release by lasmiditan. For this purpose, we have comparatively analysed the inhibition of several components of the trigeminovascular system induced by lasmiditan and sumatriptan through: ex vivo KCl-induced CGRP release from isolated dura mater, trigeminal ganglion, and trigeminal nucleus caudalis of mice; and in vivo dural vasodilation in the rat closed-cranial window model induced by endogenous (electrical stimulation and capsaicin) and exogenous CGRP. The ex vivo release of CGRP was similarly inhibited by sumatriptan and lasmiditan in all trigeminovascular system components. In vivo, intravenous (i.v.) lasmiditan or higher doses of sumatriptan significantly attenuated the vasodilatory responses to endogenous CGRP release, but not exogenous CGRP effects. These data suggest that lasmiditan prejunctionally inhibits CGRP release in peripheral and central trigeminal nerve terminals. Because lasmiditan is a lipophilic drug that crosses the blood–brain barrier, additional central sites of action remain to be determined.

Comparison of pregnenolone sulfate, pregnanolone and estradiol levels between patients with menstrually-related migraine and controls: an exploratory study

BACKGROUND

Neurosteroids affect the balance between neuroexcitation and neuroinhibition but have been little studied in migraine. We compared the serum levels of pregnenolone sulfate, pregnanolone and estradiol in women with menstrually-related migraine and controls and analysed if a correlation existed between the levels of the three hormones and history of migraine and age.

METHODS

Thirty women (mean age ± SD: 33.5 ± 7.1) with menstrually-related migraine (MM group) and 30 aged- matched controls (mean age ± SD: 30.9 ± 7.9) participated in the exploratory study. Pregnenolone sulfate and pregnanolone serum levels were analysed by liquid chromatography-tandem mass spectrometry, while estradiol levels by enzyme-linked immunosorbent assay.

RESULTS

Serum levels of pregnenolone sulfate and pregnanolone were significantly lower in the MM group than in controls (pregnenolone sulfate: P = 0.0328; pregnanolone: P = 0.0271, Student's t-test), while estradiol levels were similar. In MM group, pregnenolone sulfate serum levels were negatively correlated with history of migraine (R² = 0.1369; P = 0.0482) and age (R² = 0.2826, P = 0.0025) while pregnenolone sulfate levels were not age-related in the control group (R² = 0.04436, P = 0.4337, linear regression analysis).

CONCLUSION

Low levels of both pregnanolone, a positive allosteric modulator of the GABAA receptor, and pregnenolone sulfate, a positive allosteric modulator of the NMDA receptor, involved in memory and learning, could contribute either to headache pain or the cognitive dysfunctions reported in migraine patients. Overall, our results agree with the hypothesis that migraine is a disorder associated with a loss of neurohormonal integrity, thus supporting the therapeutic potential of restoring low neurosteroid levels in migraine treatment.

Menstrual Headache in Women with Chronic Migraine Treated with Erenumab: An Observational Case Series

BACKGROUND

We aimed to assess the differences between menstrual and non-menstrual headache in women with chronic migraine treated with erenumab.

METHODS

We included fertile women from a single center. Patients were defined as responders to erenumab if reporting a ≥50% decrease in monthly headache days, as compared to pre-treatment for more than half of the treatment period. Premenstrual days were defined as the two days preceding menstruation, while menstrual days were defined as the first three days of menstruation.

RESULTS

We included 18 women (11 erenumab responders and 7 erenumab non-responders) contributing to a total of 103 menstrual cycles and 2926 days. The proportion of headache days was higher in menstrual than in premenstrual and non-menstrual days in erenumab responders (34.4% vs. 14.8% vs. 16.3%, respectively; p < 0.001) and in erenumab non-responders (71.4% vs. 53.6% vs. 48.3%, respectively; p < 0.001). Headache days with ≥2 acute medications were higher in menstrual than in premenstrual or non-menstrual headache days in erenumab non-responders (p = 0.002) but not in erenumab responders (p = 0.620).

CONCLUSIONS

Our data suggest that migraine is more frequent during than outside menstrual days even in women treated with erenumab.

Changing levels of sex hormones and calcitonin gene-related peptide (CGRP) during a woman's life: Implications for the efficacy and safety of novel antimigraine medications

Migraine is a neurovascular disorder that is three times more prevalent in women than in men and represents a large socio-economic burden. Therefore, the development of new preventive medications is an urgent matter. Currently, calcitonin gene-related peptide (CGRP), a neuropeptide released from trigeminal fibres, is an important target for migraine treatment. Accordingly, antibodies directed against CGRP or its receptor, as well as small-molecule CGRP receptor antagonists, have been developed for the prophylactic and acute treatment of migraine. Results from clinical phase III trials show a significant decrease in migraine days and relatively mild side-effects. However, CGRP is not only present in the trigeminal nerve, but it is also abundant in perivascular nerve fibres. Moreover, CGRP levels and hormones vary between sexes and during different life stages, and hormones affect CGRP, with a seemingly greater role for CGRP in females. In this review we discuss whether these aspects could be associated with differences in response and efficacy of drugs interfering with the CGRP pathway. Furthermore, CGRP has been described as playing a protective role in ischemic events, and CGRP seems to play a larger role in cardiac ischemic events in female patients. As cardiovascular risk is increased in female migraine patients and also increases significantly in females after menopause, further research into the risk of blocking CGRP in these patients is needed.

Mal de Debarquement Syndrome: A Matter of Loops?

Introduction: Mal de Debarquement Syndrome (MdDS) is a poorly understood neurological disorder affecting mostly perimenopausal women. MdDS has been hypothesized to be a maladaptation of the vestibulo-ocular reflex, a neuroplasticity disorder, and a consequence of neurochemical imbalances and hormonal changes. Our hypothesis considers elements from these theories, but presents a novel approach based on the analysis of functional loops, according to Systems and Control Theory.

Hypothesis: MdDS is characterized by a persistent sensation of self-motion, usually occurring after sea travels. We assume the existence of a neuronal mechanism acting as an oscillator, i.e., an adaptive internal model, that may be able to cancel a sinusoidal disturbance of posture experienced aboard, due to wave motion. Thereafter, we identify this mechanism as a multi-loop neural network that spans between vestibular nuclei and the flocculonodular lobe of the cerebellum. We demonstrate that this loop system has a tendency to oscillate, which increases with increasing strength of neuronal connections. Therefore, we hypothesize that synaptic plasticity, specifically long-term potentiation, may play a role in making these oscillations poorly damped. Finally, we assume that the neuromodulator Calcitonin Gene-Related Peptide, which is modulated in perimenopausal women, exacerbates this process thus rendering the transition irreversible and consequently leading to MdDS.

Conclusion and Validation: The concept of an oscillator that becomes noxiously permanent can be used as a model for MdDS, given a high correlation between patients with MdDS and sea travels involving undulating passive motion, and an alleviation of symptoms when patients are re-exposed to similar passive motion. The mechanism could be further investigated utilizing posturography tests to evaluate if subjective perception of motion matches with objective postural instability. Neurochemical imbalances that would render individuals more susceptible to developing MdDS could be investigated through hormonal profile screening. Alterations in the connections between vestibular nuclei and cerebellum, notably GABAergic fibers, could be explored by neuroimaging techniques as well as transcranial magnetic stimulation. If our hypothesis were tested and verified, optimal targets for MdDS treatment could be found within both the neural networks and biochemical factors that are deemed to play a fundamental role in loop functioning and synaptic plasticity.

Giving Researchers a Headache - Sex and Gender Differences in Migraine

Migraine is a common neurovascular disorder affecting ~15% of the general population. Ranking second in the list of years lived with disability (YLD), people living with migraine are greatly impacted by this especially burdensome primary headache disorder. In ~30% of individuals with migraine, transient neurological symptoms occur (migraine aura) that further increase migraine burden. However, migraine burden is differential with respect to sex. Though one-year prevalences in childhood are similar, starting with puberty, migraine incidence increases at a much higher rate in females than males. Thus, migraine over the life course occurs in women three to four times more often than in men. Attacks are also more severe in women, leading to greater disability and a longer recovery period. The sex disparity in migraine is believed to be partly mediated through fluctuations in ovarian steroid hormones, especially estrogen and progesterone, although the exact mechanisms are not yet completely understood. The release of the neuropeptide calcitonin gene-related peptide (CGRP), followed by activation of the trigeminovascular system, is thought to play a key role in the migraine pathophysiology. Given the burden of migraine and its disproportionate distribution, the underlying cause(s) for the observed differences between sexes in the incidence, frequency, and intensity of migraine attacks must be better understood. Relevant biological as well as behavioral differences must be taken into account. To evaluate the scope of the existing knowledge on the issue of biological sex as well as gender differences in migraine, we conducted a systematized review of the currently available research. The review seeks to harmonize existing knowledge on the topic across the domains of biological/preclinical, clinical, and population-level research, which are traditionally synthesized and interpreted in isolation. Ultimately, we identify knowledge gaps and set priorities for further interdisciplinary and informed research on sex and gender differences as well as gender-specific therapies in migraine.

Pain perception in women with menstrually-related migraine

Background

Cyclic hormonal fluctuations influence migraine incidence and severity. Previously, we described reduced menstrual cyclicity in estradiol levels and dermal blood flow reaction to capsaicin in female migraineurs. It is unclear whether pain perception in women with migraine is influenced by the menstrual cycle.

Methods

Women with menstrually-related migraine (n = 14), healthy age-matched controls (n = 10) and postmenopausal women (n = 15) were asked to grade trigeminal and non-trigeminal painful stimuli on a numeric pain rating scale on menstrual cycle day 19–21 (mid-luteal) and day 1–2 (early follicular).

Results

In women with menstrually-related migraine, trigeminal pain remained low throughout the cycle. Controls showed increased trigeminal pain during the mid-luteal phase compared to the early follicular phase. Changes throughout the cycle were significantly different between women with MRM and controls.

Conclusion

The compromised menstrual cyclicity of pain perception in women with menstrually-related migraine parallels our earlier findings on estradiol levels and dermal blood flow.

Effects of estrogen and progesterone on the neurogenic inflammatory neuropeptides: implications for gender differences in migraine

Neurogenic inflammation including calcitonin gene-related peptide (CGRP) and substance-P (SP) release plays a pivotal role in migraine pathogenesis. Prevalence of migraine is ~ 3 folds higher in women than in men, but its underlying mechanisms remained unclear. We investigated the effects of female sex hormones estrogen and progesterone on CGRP and SP in in-vivo and ex-vivo in rats of both sexes. For in-vivo experiments, male, female and ovariectomized rats were separated into four groups (n = 7) as control, estrogen, progesterone and estrogen + progesterone, respectively. Groups received daily intraperitoneal vehicle, 17β-estradiol, progesterone and 17β-estradiol + progesterone for 5 days, respectively. For ex-vivo experiments in both sexes, isolated trigeminal ganglia and hemiskull preparations were divided into four groups (n = 6 or 8), respectively, as in-vivo groups, and administered the same test substances. CGRP and SP contents in plasma and superfusates were determined using ELISA. In in-vivo experiments, 17β-estradiol decreased CGRP levels in males and SP levels in ovariectomized rats. Progesterone increased both CGRP and SP levels in females. Their combination decreased both CGRP and SP levels in males, and only SP levels in ovariectomized rats. In ex-vivo experiments, 17β-estradiol reduced CGRP release in males and SP release in females in trigeminal ganglia. While progesterone increased CGRP release in trigeminal ganglia, it reduced SP release from hemiskulls in both sexes. Their combination restored progesterone-mediated changes in neuropeptides releases in both trigeminal ganglia and hemiskulls in both sexes. Estrogen alleviates neurogenic inflammation through modulation of CGRP and SP release. Progesterone has dual effects on these neuropeptides in different sites associated with migraine pain.

Efficacy and safety of erenumab in women with a history of menstrual migraine

BACKGROUND

We performed a post hoc, subgroup analysis of a phase 3, randomized, double-blind, placebo-controlled study of erenumab for prevention of episodic migraine (STRIVE) to determine the efficacy and safety of erenumab in women with self-reported menstrual migraine.

METHODS

Patients received placebo, erenumab 70 mg, or erenumab 140 mg subcutaneously once monthly during the 6-month double-blind treatment phase of STRIVE. Women who reported history of menstrual migraine and who were ≤ 50 years old were included in the analysis. Endpoints were change from baseline in monthly migraine days (MMD) and monthly acute migraine-specific medication days (MSMD; among patients who took acute migraine-specific medications at baseline), proportion of patients achieving ≥ 50% reduction from baseline in MMD, and incidence of adverse events.

RESULTS

Among 814 women enrolled in STRIVE, 232 (28.5%) reported a history of menstrual migraine and were ≤ 50 years old. Of the 232 patients, 214 (92%) had a baseline MMD > 5, suggesting a high proportion of women with attacks outside of the 5-day perimenstrual window (2 days before and 3 days after the start of menstruation). Information on "migraine days" includes (and does not discriminate between) perimenstrual and intermenstrual migraine attacks. Between-group differences from placebo over months 4-6 for erenumab 70 mg and 140 mg were - 1.8 (P = 0.001) and - 2.1 (P < 0.001) days for MMD and - 1.6 (P = 0.002) and - 2.4 (P < 0.001) days for acute MSMD, respectively. The odds of having a ≥ 50% reduction from baseline in MMD over months 4-6 were 2.2 (P = 0.024) and 2.8 (P = 0.002) times greater for erenumab 70 mg and 140 mg, respectively, than for placebo. Erenumab had an overall safety profile comparable to placebo.

CONCLUSION

Data from this subgroup analysis of women with menstrual migraine are consistent with data from the overall STRIVE episodic migraine population, supporting the efficacy and safety of erenumab in women who experience menstrual migraine.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02456740. Registered 28 May 2015.

Low plasma levels of calcitonin gene-related peptide in persistent post-traumatic headache attributed to mild traumatic brain injury

OBJECTIVE

To investigate the role of calcitonin gene-related peptide (CGRP) in persistent post-traumatic headache (PTH) attributed to mild traumatic brain injury (TBI).

METHODS

A total of 100 individuals with persistent PTH attributed to mild TBI and 100 age- and gender-matched healthy controls were enrolled between July 2018 and June 2019. Blood was drawn from the antecubital vein and subsequently analyzed using a validated radioimmunoassay for human CGRP. Measurements were performed on coded samples by a board-certified laboratory technician who was blind to clinical information.

RESULTS

CGRP plasma levels were lower in subjects with persistent PTH (mean, 75.8 pmol/L; SD, 26.4 pmol/L), compared with age- and gender-matched healthy controls (mean, 88.0 pmol/L; SD, 34.1 pmol/L) (p = 0.04). No correlation was found of CGRP plasma levels with monthly headache days (r = -0.11; p = 0.27), monthly migraine-like days (r = 0.15; p = 0.13), headache quality (r = -0.14; p = 0.15), or a chronic migraine-like headache phenotype (r = -0.02; p = 0.85).

CONCLUSIONS

CGRP plasma measurements are unlikely a feasible blood-based biomarker of persistent PTH. Future studies should assess whether CGRP plasma measurements can be used to predict development of persistent PTH.

Pharmacological treatment of migraine: CGRP and 5-HT beyond the triptans

Migraine is a highly disabling neurovascular disorder characterized by a severe headache (associated with nausea, photophobia and/or phonophobia), and trigeminovascular system activation involving the release of calcitonin-gene related peptide (CGRP). Novel anti-migraine drugs target CGRP signaling through either stimulation of 5-HT1F receptors on trigeminovascular nerves (resulting in inhibition of CGRP release) or direct blockade of CGRP or its receptor. Lasmiditan is a highly selective 5-HT1F receptor agonist and, unlike the triptans, is devoid of vasoconstrictive properties, allowing its use in patients with cardiovascular risk. Since lasmiditan can actively penetrate the blood-brain barrier, central therapeutic as well as side effects mediated by 5-HT1F receptor activation should be further investigated. Other novel anti-migraine drugs target CGRP signaling directly. This neuropeptide can be targeted by the monoclonal antibodies eptinezumab, fremanezumab and galcanezumab, or by CGRP-neutralizing L-aptamers called Spiegelmers. The CGRP receptor can be targeted by the monoclonal antibody erenumab, or by small-molecule antagonists called gepants. Currently, rimegepant and ubrogepant have been developed for acute migraine treatment, while atogepant is studied for migraine prophylaxis. Of these drugs targeting CGRP signaling directly, eptinezumab, erenumab, fremanezumab, galcanezumab, rimegepant and ubrogepant have been approved for clinical use, while atogepant is in the last stage before approval. Although all of these drugs seem highly promising for migraine treatment, their safety should be investigated in the long-term. Moreover, the exact mechanism(s) of action of these drugs need to be elucidated further, to increase both safety and efficacy and to increase the number of responders to the different treatments, so that all migraine patients can satisfactorily be treated.

The effect of multiple doses of ubrogepant on the pharmacokinetics of an oral contraceptive in healthy women: Results of an open-label, single-center, two-period, fixed-sequence study

Background:

Ubrogepant is a novel, oral calcitonin gene–related peptide receptor antagonist for acute treatment of migraine. This study evaluated potential drug–drug interactions between ubrogepant and an oral contraceptive containing ethinyl estradiol (EE) and norgestimate (NGM).

Methods:

This open-label, single-center, two-period, fixed-sequence study enrolled healthy, postmenopausal or oophorectomized, adult women. In period 1, participants received a single oral dose of EE 0.035 mg/NGM 0.25 mg (EE-NGM) followed by a 7-day washout. In period 2, participants received oral ubrogepant 50 mg daily on days 1–14; single-dose EE-NGM was coadministered with ubrogepant on day 10. Pharmacokinetic parameters for plasma EE and norelgestromin (NGMN) were compared with and without ubrogepant.

Results:

Twenty-two participants aged 46–66 years were enrolled; 21 completed the study. Geometric mean ratios and 90% confidence intervals for the comparison of EE-NGM + ubrogepant to EE-NGM alone were contained within 0.80 and 1.25 for area under the plasma drug concentration–time curve (AUC) from time zero to infinity (AUC0–∞; 0.96 [0.91, 1.01]) and C max (0.91 [0.82, 1.004]) of NGMN and AUC0–∞ (0.97 [0.93, 1.01]) of EE, but not C max of EE (0.74 [0.69, 0.79]). Median t max of EE was delayed following EE-NGM + ubrogepant (3.0 h) versus EE-NGM alone (median of 1.5 h), whereas median t max of NGMN was unchanged (1.5 h). Geometric mean apparent terminal half-life ( t ½) was similar with and without ubrogepant for EE (23 vs. 21 h) and NGMN (36 h both conditions). All ubrogepant-related adverse events were mild or moderate.

Conclusion:

Ubrogepant did not demonstrate potential for clinically meaningful drug–drug interactions with an EE-NGM oral contraceptive.

Trial registration:

Not applicable (phase 1 trial)

Contribution of intraganglionic CGRP to migraine-like responses in male and female rats

Objective

To evaluate whether intraganglionic calcitonin gene-related peptide induced differential migraine-like responses in male and female rats.

Methods

Calcitonin gene-related peptide was injected in the trigeminal ganglion of male and female rats followed by assessment of periorbital mechanical allodynia with von Frey hairs. The influence of systemic treatment with sumatriptan or intraganglionic treatment with minocycline and propentofylline was determined on the calcitonin gene-related peptide-induced mechanical allodynia in male and female rats. One additional group was exposed to an aversive light 24 h after calcitonin gene-related peptide priming, followed by evaluation of periorbital mechanical threshold, and another group was tested in the elevated-plus maze.

Results

Intraganglionar calcitonin gene-related peptide-induced periorbital mechanical allodynia in female (0.5 to 6 h) and male rats (0.5 to 4 h). Systemic sumatriptan briefly attenuated the mechanical allodynia, but intraganglionar minocycline or propentofylline injection was effective only in male rats. Calcitonin gene-related peptide induced photic sensitivity in female and male rats (lasting 4 h and 1 h, respectively), as well as anxiety-like behavior.

Conclusions

Intraganglionar calcitonin gene-related peptide may play a major role in migraine-like responses, including periorbital mechanical allodynia, light sensitivity and anxiety like-behavior. Female rats are likely to be more susceptible to calcitonin gene-related peptide effects and a better understanding of the sexual dimorphism in calcitonin gene-related peptide signaling may help to improve migraine therapy.

Migraine: navigating the hormonal minefield

Migraine affects 959 million people worldwide,1 with the highest prevalence being in women of childbearing age. The interplay between female hormones and migraine can be a challenging area to navigate since issues relating to pregnancy, contraception and the menopause are often out of the neurology comfort zone. This review aims to help the neurologist to manage women with migraine, from menarche to menopause.

Effect of desogestrel 75 µg on headache frequency and intensity in women with migraine: a prospective controlled trial

Objective: In contrast with combined hormonal contraception, progestin-only contraception is not associated with an increase in venous thromboembolism or stroke. Women with migraine are at increased risk of ischaemic stroke. Several studies have reported a reduction in migraine frequency and intensity with desogestrel 75 µg, a progestin-only pill. At present the quality of data is limited by retrospective study designs, lack of control groups and small sample sizes. We present the first prospective nonrandomised controlled trial. Methods: A total of 150 women with migraine visiting our clinic for contraceptive counselling were screened. The intervention group comprised women who opted for contraception with desogestrel (n = 98); the control group comprised women who continued their usual contraceptive (n = 36). Participants completed daily diaries for 90 days before the intervention and 180 days after the intervention. Results: In the intervention group, we found improvements in migraine frequency (p < .001), migraine intensity (p < .001) and the number of triptans used (p < .001). These improvements were already significant after 90 days of desogestrel use (p < .001). Disability scores also decreased significantly. No improvement was seen in the nonintervention group. Conclusion: These data demonstrate for the first time in a prospective controlled setting that daily use of the progestin desogestrel is associated with a decrease in migraine frequency, migraine intensity and pain medication use in women with migraine, with and without aura, who had previously been experiencing at least three days of migraine per month. Trial registration: The study is registered in the University of Zürich database ( www.research-projects.uzh.ch/unizh.htm ).

Effects of two isometheptene enantiomers in isolated human blood vessels and rat middle meningeal artery - potential antimigraine efficacy

Background

Racemic isometheptene [(RS)-isometheptene] is an antimigraine drug that due to its cardiovascular side-effects was separated into its enantiomers, (R)- and (S)-isometheptene. This study set out to characterize the contribution of each enantiomer to its vasoactive profile. Moreover, rat neurogenic dural vasodilatation was used to explore their antimigraine mechanism of action.

Methods

Human blood vessel segments (middle meningeal artery, proximal and distal coronary arteries, and saphenous vein) were mounted in organ baths and concentration response curves to isometheptene were constructed. Calcitonin gene-related peptide (CGRP)-induced neurogenic dural vasodilation was elicited in the presence of the enantiomers using a rat closed cranial window model.

Results

The isometheptene enantiomers did not induce any significant contraction in human blood vessels, except in the middle meningeal artery, when they were administered at the highest concentration (100 μM). Interestingly in rats, (S)-isometheptene induced more pronounced vasopressor responses than (R)-isometheptene. However, none of these compounds affected the CGRP-induced vasodilator responses.

Conclusion

The isometheptene enantiomers displayed a relatively safe peripheral vascular profile, as they failed to constrict the human coronary artery. These compounds do not appear to modulate neurogenic dural CGRP release, therefore, their antimigraine site of action remains to be determined.

Male and female sex hormones in primary headaches

BACKGROUND

The three primary headaches, tension-type headache, migraine and cluster headache, occur in both genders, but all seem to have a sex-specific prevalence. These gender differences suggest that both male and female sex hormones could have an influence on the course of primary headaches. This review aims to summarise the most relevant and recent literature on this topic.

METHODS

Two independent reviewers searched PUBMED in a systematic manner. Search strings were composed using the terms LH, FSH, progesteron*, estrogen*, DHEA*, prolactin, testosterone, androgen*, headach*, migrain*, "tension type" or cluster. A timeframe was set limiting the search to articles published in the last 20 years, after January 1st 1997.

RESULTS

Migraine tends to follow a classic temporal pattern throughout a woman's life corresponding to the fluctuation of estrogen in the different reproductive stages. The estrogen withdrawal hypothesis forms the basis for most of the assumptions made on this behalf. The role of other hormones as well as the importance of sex hormones in other primary headaches is far less studied.

CONCLUSION

The available literature mainly covers the role of sex hormones in migraine in women. Detailed studies especially in the elderly of both sexes and in cluster headache and tension-type headache are warranted to fully elucidate the role of these hormones in all primary headaches.

Characterization of the trigeminovascular actions of several adenosine A2A receptor antagonists in an in vivo rat model of migraine

BACKGROUND

Migraine is considered a neurovascular disorder, but its pathophysiological mechanisms are not yet fully understood. Adenosine has been shown to increase in plasma during migraine attacks and to induce vasodilation in several blood vessels; however, it remains unknown whether adenosine can interact with the trigeminovascular system. Moreover, caffeine, a non-selective adenosine receptor antagonist, is included in many over the counter anti-headache/migraine treatments.

METHODS

This study used the rat closed cranial window method to investigate in vivo the effects of the adenosine A_2A receptor antagonists with varying selectivity over A₁ receptors; JNJ-39928122, JNJ-40529749, JNJ-41942914, JNJ-40064440 or JNJ-41501798 (0.3-10 mg/kg) on the vasodilation of the middle meningeal artery produced by either CGS21680 (an adenosine A_2A receptor agonist) or endogenous CGRP (released by periarterial electrical stimulation).

RESULTS

Regarding the dural meningeal vasodilation produced neurogenically or pharmacologically, all JNJ antagonists: (i) did not affect neurogenic vasodilation but (ii) blocked the vasodilation produced by CGS21680, with a blocking potency directly related to their additional affinity for the adenosine A₁ receptor.

CONCLUSIONS

These results suggest that vascular adenosine A_2A (and, to a certain extent, also A₁) receptors mediate the CGS21680-induced meningeal vasodilation. These receptors do not appear to modulate prejunctionally the sensory release of CGRP. Prevention of meningeal arterial dilation might be predictive for anti-migraine drugs, and since none of these JNJ antagonists modified per se blood pressure, selective A_2A receptor antagonism may offer a novel approach to antimigraine therapy which remains to be investigated in clinical trials.