Prolactin and oxytocin: potential targets for migraine treatment

Effectiveness of anti-CGRP monoclonal antibodies and onabotulinumtoxinA in menstrually-related migraine: The unmet need of perimenstrual headache days

BackgroundData on the effectiveness of preventive treatments on menstrually-related migraine (MRM) is scarce. Our objective was to analyze the efficacy of anti-calcitonin gene-related peptide monoclonal antibodies (anti-CGRP mAbs) and onabotulinumtoxinA (BTX-A) in the reduction of perimenstrual headache days (PHD) and perimenstrual migraine days (PMD) compared to non-perimenstrual headache days (non-PHD) and non-perimenstrual migraine days (non-PMD) per month in women with MRM.MethodsA retrospective study was conducted including females with menstruation and headache records, treated with either anti-CGRP mAbs or BTX-A. Patients completed e-Diary one month before and three months after preventive treatment. We collected clinical data and analyzed PHD/PMD and non-PHD/non-PMD before and after treatment. Additional analyses included PHD/PMD and non-PHD/non-PMD comparisons grouped by aura, episodic/chronic migraine, treatment and contraceptive intake.ResultsWe analyzed data from 113 females with a median (range) age of 39.0 (33.0-45.0) years. When combining patients treated with anti-CGRP mAbs or BTX-A, a median (range) of 2.0 (2.0-3.0) PHD/month (corresponding to 13.6% baseline monthly headache days (MHD)) and 13.0 (9.0-17.0) non-PHD/month pre-treatment was observed. From these, 2.0 (1.0-3.0) were PMD/month, and 7.0 (4.0-11.0) were non-PMD/month. After treatment, the median PHD/month was 2.0 (1.0-3.0) (corresponding to 16.67% of MHD) (p = 0.085), and 8.0 (5.0-13.0) were non-PHD/month (p < 0.001); from these, 1.0 (0.0-3.0) were PMD/month (proportion difference, p = 0.035) and 4.0 (2.0-7.0) were non-PMD (proportion difference, p < 0.001). When analyzing grouped by treatment, only patients treated with anti-CGRP experienced a reduction in PMD. No statistically significant differences in clinical factors (aura, migraine diagnosis, contraceptive intake) between PHD/non-PHD or PMD/non-PMD, either pre- or post-treatment. A higher probability risk of headache and migraine during the perimenstrual window was observed independently of the treatment received (odds ratio = 1.637, 95% confidence interval = 1.356-1.984, p < 0.001).ConclusionsThree-month treatment with anti-CGRP mAbs or BTX-A effectively reduced non-PHD and non-PMD but had limited effect on PHD/PMD because headache probability risk was higher during the perimenstrual window after treatment.

Cortical Potentiation in Chronic Neuropathic Pain and the Future Treatment

Pain, or the ability to feel pain and express the unpleasantness caused by peripheral injuries, are functions of the central nervous system. From peripheral sensory nerve terminals to certain cortical regions of the brain, activation of related neural networks underlies the sensory process. Recently, our knowledge of pain has been increasing dramatically, due to the advancement of scientific approaches. We no longer see the brain as a random matrix for pain but, rather, we are able to identify the step-by-step selective signaling proteins, neurons, and networks that preferentially contribute to the process of chronic pain and its related negative emotions, like anxiety and fear. However, there is still lacking the selective and effective drugs and methods for the treatment of chronic pain clinically. While first-line drugs for acute pain and mental diseases are also applied for the clinical management of chronic pain, their prolonged usage always causes serious side effects. In this short review, we will update and summarize the recent progress in this field and mainly focus on the roles of neural networks and synaptic mechanisms in chronic neuropathic pain. Furthermore, potential drug targets (such as plasticity-related signaling molecules, ionic channels, cytokines, and neuropeptides) and methods for the management of chronic neuropathic pain will be discussed as well. We hope this review can provide new, valuable insight into the treatment of chronic neuropathic pain.

Migraine in men

BACKGROUND

Migraine is a common primary headache disorder, less frequently affecting men than women, and often regarded as predominantly a "women's disease." Despite this, migraine in men presents with unique characteristics in terms of symptoms, treatment responses, comorbidities, and pain perception. Historically, research has focused more on migraine in women, overlooking critical male-specific aspects.

RESULTS

This review delves into the epidemiology, clinical presentation, and particular challenges of diagnosing and managing migraine in men. It addresses sex-specific triggers, hormonal influences, and comorbid conditions affecting migraine prevalence and severity in men. Additionally, the review evaluates current therapeutic strategies, underscoring the necessity for individualized approaches. Men with migraine often exhibit atypical symptoms compared to the ICHD-3 criteria and are less likely to report common associated symptoms. They also tend to have fewer psychological comorbidities, respond more favorably to pharmacological treatments, yet are less likely to seek medical support. The reasons for these sex disparities are complex, involving biological, psychosocial, and cultural factors, such as brain structural differences, differences in functional responses to painful stimuli, hormonal effects, and behavioral influences like adherence to masculine norms and stigma.

CONCLUSION

Men are underrepresented in clinical migraine research. In contrast, preclinical studies often focus solely in male animals as a result of various misconceptions. This disparity necessitates greater focus on sex-specific aspects of migraine to enhance diagnosis, treatment, and research. Addressing stigma, increasing healthcare access, and ensuring balanced sex and gender representation in future studies is crucial for a comprehensive understanding and effective management of migraine for all patients.

Prolactin-induced sensitization of trigeminal nociceptors promotes migraine co-morbidity in endometriosis

BACKGROUND

Women with endometriosis are more likely to have migraine. The mechanisms underlying this co-morbidity are unknown. Prolactin, a neurohormone secreted and released into circulation from the anterior pituitary, can sensitize sensory neurons from female, but not male, rodents, monkeys and human donors.

METHODS

We used a syngeneic model of endometriosis to determine whether elevated prolactin levels can sensitize trigeminal ganglion neurons and increase vulnerability to migraine pain.

RESULTS

Mice with endometriotic lesions showed increased serum prolactin levels and developed persistent abdominal, but not cephalic, allodynia. However, inhalation of a transient receptor potential ankyrin 1 agonist, umbellulone, a known environmental trigger of headache in some patients, elicited cephalic allodynia in mice with endometriosis but not sham controls, suggesting that endometriosis can promote sensitization of trigeminal neurons and migraine attacks. Endometriosis dysregulated the expression of prolactin receptor isoforms in trigeminal neurons and increased their excitability measured by in vitro patch clamp electrophysiology. Inhibition of pituitary prolactin following a 2-week treatment with a dopamine receptor agonist, cabergoline, prevented cephalic allodynia elicited by activation of trigeminal afferents with umbellulone. Cabergoline treatment also normalized the expression of prolactin receptor isoforms in trigeminal ganglia and the hyperexcitability of trigeminal neurons.

CONCLUSIONS

These data demonstrate that circulating prolactin in endometriosis promotes vulnerability to migraine through sensitization of trigeminal afferents. Clinically available dopamine receptor agonists or novel monoclonal antibodies targeting prolactin signaling may be effective for migraine prevention in women with endometriosis.

[Biochemical features of migraine pathogenesis]

The article addresses the main mechanisms of migraine pathogenesis in terms of biochemical features (neurotransmitter metabolism, neurochemistry, neurophysiology, and neurogenetics). The effect of hormones, electrolytes (magnesium, calcium, sodium), vitamins (vitamin D, B12), and other biologically active molecules (melatonin, L-carnitine, L-tryptophan) on the course of the disease is considered. Including some laboratory tests in the migraine diagnostic algorithm helps identify the secondary nature of headache and/or dizziness, manage therapeutic approaches, and adjust the prognosis and treatment outcomes.

Recent advances of electrochemical and optical point-of-care biosensors for detecting neurotransmitter serotonin biomarkers

Since its discovery in 1984, the monoamine serotonin (5-HT) has been recognized for its critical role as a neuromodulator in both the central and peripheral nervous systems. Recent research reveals that serotonin also significantly influences various neuronal activities. Historically, it was believed that peripheral serotonin, produced by tryptophan hydroxylase in intestinal cells, functioned primarily as a hormone. However, new insights have expanded its known roles, necessitating advanced detection methods. Biosensors have emerged as indispensable tools in biomedical diagnostics, enabling the rapid and minimally invasive detection of target analytes with high spatial and temporal resolution. This review summarizes the progress made in the past decade in developing optical and electrochemical biosensors for serotonin detection. We evaluate various sensing strategies that optimize performance in terms of detection limits, sensitivity, and specificity. The study also explores recent innovations in biosensing technologies utilizing surface-modified electrodes with nanomaterials, including gold, graphite, carbon nanotubes, and metal oxide particles. Applications range from in vivo studies to chemical imaging and diagnostics, highlighting future prospects in the field.

Breastfeeding-Related Adverse Drug Reactions of Triptans: A Descriptive Analysis Using Four Pharmacovigilance Databases

Objective: Migraine attacks are common in women of reproductive age. Although attacks are often less severe and less frequent during pregnancy, they regularly reoccur shortly after delivery. When first-line analgesic treatment is insufficient, triptans may be used for acute treatment of migraine attacks. Milk levels of occasional triptan use have shown to be low, and no adverse effects in breastfed infants have been reported. However, the available knowledge on the safety of triptans during breastfeeding is still limited. Methods: Four (inter)national pharmacovigilance databases were searched for breastfeeding related adverse drug reactions of triptans. These included the Dutch Pregnancy Drug Register and three databases of spontaneous reports (Netherlands Pharmacovigilance Centre Lareb, the European Medicines Agency [EudraVigilance], and the World Health Organization [VigiBase]). Results: A total of 26 reports on 27 breastfeeding related adverse drug reactions were identified (one report involved two separate adverse drug reactions). These involve three main complaints: painful breasts and/or nipples, painful milk ejection reflex, and a decrease in milk production. Discussion and Conclusion: The hypothesized pharmacological mechanism relates to the serotonin-receptor agonistic properties of triptans. These may lead to vasoconstriction in the breasts and nipples, including the vasculature surrounding the milk ducts and alveoli, and may also influence the hormonal function and levels of prolactin. The reported adverse drug reactions do not negatively impact the overall compatibility of triptans with breastfeeding. However, breastfeeding women may experience them as unsettling. Awareness of these potential adverse drug reactions is essential and should be weighed against the potential adverse effects of (untreated) symptoms of migraine attacks.

PACAP-38 and sex hormones in women with migraine: exploratory analysis of a cross-sectional, matched cohort study

BACKGROUND

Endogeneous and exogeneous sex hormones can impact the frequency and severity of migraine attacks, but the underlying mechanisms are poorly understood. In this study, we investigate the relationship between female sex hormones and Pituitary Adenylate Cyclase-Activating Polypeptide-38 (PACAP-38) concentrations in plasma of women with migraine and healthy controls, aiming to elucidate potential hormonal influences on PACAP dynamics and their relevance to migraine pathophysiology.

METHODS

This analysis is part of a cross-sectional, matched-cohort study. We recruited two groups of women with episodic migraine: one with a regular menstrual cycle (M-RMC) and another undergoing combined oral contraceptive treatment (M-COC). Additionally, we included corresponding age-matched control groups without migraine for both categories (C-RMC and C-COC). For participants with a RMC, the study visits were scheduled during the perimenstrual period (menstrual cycle day 2 ± 2) and periovulatory period (day 13 ± 2). Participants using COC were examined at day 4 ± 2 of the hormone-free interval and between day 7-14 of the hormone intake phase. During these visits, PACAP-38 concentrations in plasma were measured using a commercial Enzyme-linked-immunosorbent assay (ELISA) kit.

RESULTS

The study included 120 women, with 30 participants in each group. Women with migraine and a RMC had significantly higher PACAP-38 plasma concentrations compared to healthy controls at both study visits [day 2 ± 2: M-RMC: 2547.41 pg/ml (IQR 814.27 - 4473.48) vs. C-RMC: 1129.49 pg/ml (IQR 257.34 - 2684.88), p = 0.025; day 13 ± 2: M-RMC: 3098.89 pg/ml (IQR 1186.29 - 4379.47) vs. C-RMC: 1626.89 (IQR 383.83 - 3038.36), p = 0.028]. In contrast, PACAP-38 levels were comparable between migraine and control groups receiving COC. Women with migraine and a RMC exhibited higher PACAP-38 concentrations during menstruation compared to those using COC during the hormone-free interval.

CONCLUSION

Systemic PACAP-38 concentrations in women vary based on the presence of migraine diagnosis and their hormonal status.

Female-selective mechanisms promoting migraine

Sexual dimorphism has been revealed for many neurological disorders including chronic pain. Prelicinal studies and post-mortem analyses from male and female human donors reveal sexual dimorphism of nociceptors at transcript, protein and functional levels suggesting different mechanisms that may promote pain in men and women. Migraine is a common female-prevalent neurological disorder that is characterized by painful and debilitating headache. Prolactin is a neurohormone that circulates at higher levels in females and that has been implicated clinically in migraine. Prolactin sensitizes sensory neurons from female mice, non-human primates and humans revealing a female-selective pain mechanism that is conserved evolutionarily and likely translationally relevant. Prolactin produces female-selective migraine-like pain behaviors in rodents and enhances the release of calcitonin gene-related peptide (CGRP), a neurotransmitter that is causal in promoting migraine in many patients. CGRP, like prolactin, produces female-selective migraine-like pain behaviors. Consistent with these observations, publicly available clinical data indicate that small molecule CGRP-receptor antagonists are preferentially effective in treatment of acute migraine therapy in women. Collectively, these observations support the conclusion of qualitative sex differences promoting migraine pain providing the opportunity to tailor therapies based on patient sex for improved outcomes. Additionally, patient sex should be considered in design of clinical trials for migraine as well as for pain and reassessment of past trials may be warranted.

Pharmacological management of migraine: current strategies and future directions

INTRODUCTION

Migraine is a complex neurological disorder that affects a significant portion of the global population. As traditional pharmacological approaches often fall short in alleviating symptoms, the development of innovative therapies has garnered significant interest. This text aims to summarize the current pharmacological options for managing migraine and to explore the potential impact of novel therapies.

AREAS COVERED

We focused on conventional treatments, emerging therapies, and novel compounds in clinical development, including therapies targeting the trigeminovascular system, cannabis-based therapies, hormonal and metabolic therapies, and other options. English peer-reviewed articles were searched in PubMed, Scopus, and ClinicalTrials.gov electronic databases.

EXPERT OPINION

Several novel treatment options for migraine have become available in recent years. Emerging pharmacological therapies targeting the trigeminovascular system, cannabis-based therapies, hormonal and metabolic interventions, and other emerging treatment modalities, may prove to be valuable for the treatment of migraine. Further research, clinical trials, and substantiated evidence are necessary to validate the efficacy, safety, and long-term outcomes of these therapeutic options.

Oxytocin and vasopressin signaling in health and disease

Neurohypophysial peptides are ancient and evolutionarily highly conserved neuropeptides that regulate many crucial physiological functions in vertebrates and invertebrates. The human neurohypophysial oxytocin/vasopressin (OT/VP) signaling system with its four receptors has become an attractive drug target for a variety of diseases, including cancer, pain, cardiovascular indications, and neurological disorders. Despite its promise, drug development faces hurdles, including signaling complexity, selectivity and off-target concerns, translational interspecies differences, and inefficient drug delivery. In this review we dive into the complexity of the OT/VP signaling system in health and disease, provide an overview of relevant pharmacological probes, and discuss the latest trends in therapeutic lead discovery and drug development.

Potential treatment targets for migraine: emerging options and future prospects

Migraine is a leading cause of disability worldwide. Despite the recent approval of several calcitonin gene-related peptide-targeted therapies, many people with migraine do not achieve satisfactory headache improvement with currently available therapies and there continues to be an unmet need for effective and tolerable migraine-specific treatments. Exploring additional targets that have compelling evidence for their involvement in modulating migraine pathways is therefore imperative. Potential new therapies for migraine include pathways involved in nociception, regulation of homoeostasis, modulation of vasodilation, and reward circuits. Animal and human studies show that these targets are expressed in regions of the CNS and peripheral nervous system that are involved in pain processing, indicating that these targets might be regarded as promising for the discovery of new migraine therapies. Future studies will require assessment of whether targets are suitable for therapeutic modulation, including assessment of specificity, affinity, solubility, stability, efficacy, and safety.

Understanding the Biological Relationship between Migraine and Depression

Migraine is a highly prevalent neurological disorder. Among the risk factors identified, psychiatric comorbidities, such as depression, seem to play an important role in its onset and clinical course. Patients with migraine are 2.5 times more likely to develop a depressive disorder; this risk becomes even higher in patients suffering from chronic migraine or migraine with aura. This relationship is bidirectional, since depression also predicts an earlier/worse onset of migraine, increasing the risk of migraine chronicity and, consequently, requiring a higher healthcare expenditure compared to migraine alone. All these data suggest that migraine and depression may share overlapping biological mechanisms. Herein, this review explores this topic in further detail: firstly, by introducing the common epidemiological and risk factors for this comorbidity; secondly, by focusing on providing the cumulative evidence of common biological aspects, with a particular emphasis on the serotoninergic system, neuropeptides such as calcitonin-gene-related peptide (CGRP), pituitary adenylate cyclase-activating polypeptide (PACAP), substance P, neuropeptide Y and orexins, sexual hormones, and the immune system; lastly, by remarking on the future challenges required to elucidate the etiopathological mechanisms of migraine and depression and providing updated information regarding new key targets for the pharmacological treatment of these clinical entities.

Exploring the Connection between Migraines and Pregnancy: The Impact of Physical Activity on Symptom Management

Migraine is a prevalent neurological disorder that significantly impacts the quality of life for affected individuals. The pathogenesis behind migraines is not yet fully understood, but hormonal changes, especially fluctuations in, estrogen and progesterone levels, have a significant role in the susceptibility of women to migraines. Pregnancy introduces a unique set of challenges for women who experience migraines, as they must navigate the complexities of managing their condition while safeguarding the health of both them and their unborn child. Pharmacological options for treating migraines during pregnancy are limited, and, therefore, there is a growing interest in exploring alternative approaches to migraine symptom relief and management. Physical activity during pregnancy provides a range of benefits, and it has gained attention as a potentially valuable tool for alleviating migraine symptoms in pregnant patients. This review explores the intricate relationship between migraines and pregnancy, emphasizing how physical activity and other alternative approaches may influence the frequency, severity, and overall experience of migraines during pregnancy. Through collaboration with healthcare providers and the adoption of personalized management strategies, women can strike a balance that supports both their own well-being and the healthy development of their unborn child. By examining existing research and emerging insights, we aim to provide a comprehensive understanding of the potential benefits and considerations of incorporating physical activity and other treatment options into migraine management strategies for pregnant women. Further research is needed to elucidate the specific mechanisms linking migraines, pregnancy, and physical activity, enabling the development of more targeted interventions and guidelines.

Considerations for hormonal therapy in migraine patients: a critical review of current practice

INTRODUCTION

Migraine, a neurovascular headache disorder, is a leading cause of disability worldwide. Within the multifaceted pathophysiology of migraine, hormonal fluctuations play an evident triggering and exacerbating role, pointing toward the need for identification and proper usage of both existing and new hormonal targets in migraine treatment.

AREAS COVERED

With a threefold higher incidence of migraine in women than in men, the authors delve into sex hormone-related events in migraine patients. A comprehensive overview is given of existing hormonal therapies, including oral contraceptives, intrauterine devices, transdermal and subcutaneous estradiol patches, gnRH-agonists, oral testosterone, and 5α reductase inhibitors. The authors discuss their effectiveness and risks, noting their suitability for different patient profiles. Next, novel evolving hormonal treatments, such as oxytocin and prolactin, are explored. Lastly, the authors cover hormonal conditions associated with migraine, such as polycystic ovary syndrome, endometriosis, and transgender persons receiving gender affirming hormone therapy, aiming to provide more personalized and effective solutions for migraine management.

EXPERT OPINION

Rigorous research into both existing and new hormonal targets, as well as the underlying pathophysiology, is needed to support a tailored approach in migraine treatment, in an ongoing effort to alleviate the impact of migraine on individuals and society.

Retrospective analysis on the efficacy of epidural labor analgesia on early breast feeding after vaginal delivery

BACKGROUND

Breastfeeding is essential for infants and mothers. Epidural labor analgesia is used frequently to alleviate pain during vaginal delivery. Studies have found that epidural labor analgesia potentially have negative effects on postpartum breastfeeding. However, the efficacy of epidural labor analgesia on early breastfeeding after vaginal delivery is unclear. Therefore, a retrospective analysis was performed to illuminate the efficacy of epidural labor analgesia on postpartum breast feeding.

METHODS

A total of 392 women who received vaginal delivery in the Second People's Hospital of Foshan from July 2022 to June 2023 were selected for this study, and all women received epidural labor analgesia and were divided into three groups according to the efficacy of labor analgesia. There were three groups: parturients with VAS scores < 3 were divided into Group E (n = 192), parturients with VAS scores 4-6 were divided into Group M (n = 127), and parturients with VAS scores > 7 were divided into Group P (n = 73). The labor process, lactation initiation time, and incidence of delayed onset of lactation were analyzed. The lactation volume and time and LATCH score at 24, 48 and 72 h after vaginal delivery were also analyzed.

RESULTS

There was no significant difference in labor process times among the three groups (P > 0.05). The cases of prolactin use in Group M were less than those in Group E and Group P, with a significant difference (all P < 0.05). There was no significant difference in cases of prolactin use between Group E and Group P (P > 0.05). The lactation initiation time in Group M was significantly shorter than those in Group E and Group P (all P>0.05). There was no significant difference in lactation initiation time after vaginal delivery between Group E and Group P (P>0.05). The incidence of delayed onset of lactation in Group M was significantly lower those that in Group E and Group P (all P < 0.05). There was no statistically significant difference in the incidence of delayed onset of lactation between Group E and Group P (P > 0.05). The lactation volumes at 24, 48 and 72 h after vaginal delivery in Group M were significantly higher than those in Group E and Group P (all P < 0.05). There was no significant difference in lactation volume at 24, 48 and 72 h after vaginal delivery between Group E and Group P (P > 0.05). The lactation times at 24, 48 and 72 h after vaginal delivery in Group M were significantly higher than those in Group E and Group P (all P < 0.05). There was no significant difference in lactation times at 24, 48 and 72 h after vaginal delivery between Group E and Group P (P > 0.05). There was no significant difference in LATCH scores at 24, 48 and 72 h after vaginal delivery among the three groups (all P > 0.05).

CONCLUSIONS

Compared with labor analgesia with excellent and poor analgesia efficacy, labor analgesia with moderate analgesia efficacy has fewer cases of prolactin use, more lactation volume and time, a shorter lactation initiation time, a lower incidence of delayed onset of lactation and no effect on the LATCH score of breastfeeding.

Molecular and Cellular Neurobiology of Circadian and Circannual Rhythms in Migraine: A Narrative Review

Migraine-a primary headache-has circadian and circannual rhythms in the onset of attacks. The circadian and circannual rhythms involve the hypothalamus, which is strongly associated with pain processing in migraines. Moreover, the role of melatonin in circadian rhythms has been implied in the pathophysiology of migraines. However, the prophylactic effect of melatonin in migraines is controversial. Calcitonin gene-related peptide (CGRP) has recently attracted attention in the pathophysiology and treatment of migraines. Pituitary adenylate cyclase-activating peptide (PACAP)-a neuropeptide identical to CGRP-is a potential therapeutic target after CGRP. PACAP is involved in the regulation of circadian entrainment to light. This review provides an overview of circadian and circannual rhythms in the hypothalamus and describes the relationship between migraines and the molecular and cellular neurobiology of circadian and circannual rhythms. Furthermore, the potential clinical applications of PACAP are presented.