(137) Meningeal application of prolactin and CGRP produces female specific migraine-related behavior in rodents

Increased serum prolactin level may indicate more migraine attack frequency

OBJECTIVES

Migraine is a common, multifactorial disorder. The exact pathomechanism of migraine remains unclear. Studies have revealed changes in serum prolactin (PRL) levels in relation to migraine, although the results have been inconsistent. The present case-control study assessed the serum level of prolactin in migraine patients.

MATERIALS AND METHODS

In this case-control study, participants were divided into chronic migraine (CM; n = 39), episodic migraine in ictal (during an attack), and interictal (between attacks) phases (n = 63, n = 37, respectively) along with 30 age- and sex-matched headache-free controls. After obtaining demographic, anthropometric data, and headache characteristics, blood samples were gathered and analyzed to evaluate the serum levels of prolactin (ng/mL).

RESULTS

A significant difference was observed between the control, CM, and ictal EM, and interictal EM groups. The mean ± SD serum prolactin levels of the chronic migraineurs (1.82 ± 0.94) and those with ictal EM (1.93 ± 1.70) were comparable and were significantly higher than for interictal EM patients (0.82 ± 0.46) and the headache-free control subjects (0.49 ± 0.15; p < .001). Although the mean serum concentration of prolactin for the interictal EM group tended to be higher than for control individuals, this difference was not statistically significant. The Spearman's correlation test also showed significant correlations between the serum prolactin levels and the number of headaches days among migraineurs.

CONCLUSION

The findings suggest that there might be an association between increased prolactin concentrations and migraine headache induction and progression. Further detailed and well-designed studies are needed to confirm the importance of serum prolactin levels in the pathogenesis of migraine headaches.

CGRP in Animal Models of Migraine

With the approval of calcitonin gene-related peptide (CGRP) and CGRP receptor monoclonal antibodies by the Federal Drug Administration, a new era in the treatment of migraine patients is beginning. However, there are still many unknowns in terms of CGRP mechanisms of action that need to be elucidated to allow new advances in migraine therapies. CGRP has been studied both clinically and preclinically since its discovery. Here we review some of the preclinical data regarding CGRP in animal models of migraine.

Evidence for hyperprolactinemia in migraineurs: a systematic review and meta-analysis

BACKGROUND

One of the hypothalamus-pituitary axis hormones which may play a crucial role in pathophysiology of migraine is prolactin which is secreted from anterior pituitary gland and synthesized by various immune system cells as well. Whether prolactin blood levels can affect the migraine pathogenesis is an open question. Therefore, investigating prolactin circulatory levels in migraineurs may pave the way to underpin the mechanisms of migraine pathophysiology at biochemical levels. In the current investigation, the prolactin blood levels in the migraine subjects were investigated using systematic review and meta-analysis.

METHODS

Using online and specialized biomedical databases including Google Scholar, Medline, Pubmed, Pubmed Central, Embase, and Scopus, without the beginning date restriction until Feb 2019, the systematic review retrieved 11 publications in this systematic review after fulfilling for the inclusion and exclusion criteria. For heterogeneity, extent calculation statistical testing was applied. In the present study, the levels of circulatory prolactin in migraineurs assessed using standardized mean difference (SMD) as the effect size.

RESULTS

Q quantity and I²% statistic index showed a high heterogeneity in the 13 selected publications (188.370 and 92.568, respectively) and random-effects model was chosen for further analyses. The meta-analysis on a total number of 460 migraineurs and 429 healthy controls found that the weighted pooled SMD for the effects of prolactin blood concentrations on migraine pathogenesis was as follows: SMD = 1.435 (95% confidence interval, 0.854-2.015).

CONCLUSION

The current investigation presents evidence that prolactin blood levels are higher in migraineurs than healthy subjects.

Predictors of allodynia in persons with migraine: Results from the Migraine in America Symptoms and Treatment (MAST) study

Background

Cutaneous allodynia is a common clinical feature of migraine that has been associated with reduced efficacy of acute migraine treatments and an increased risk of disease progression.

Objective

Identify factors associated with allodynia in a sample of adults with migraine.

Methods

An online survey panel was used to identify adults with migraine who averaged at least 1 monthly headache day over the previous 3 months. Data on sociodemographics, headache frequency, headache pain intensity, migraine symptom severity, medication use, depression and anxiety, and cutaneous allodynia (via the Allodynia Symptom Checklist) were obtained. Binary logistic modeling predicted the presence of allodynia. Odds ratios and 95% confidence intervals (CI) were calculated.

Results

In total, 15,133 individuals with migraine met the eligibility criteria. Mean age was 43.1 years, 73.0% were female, and 81.0% were Caucasian. Allodynia was present in 39.9%. The fully adjusted model, controlling for sociodemographics and headache features, demonstrated that allodynia was significantly associated with a higher migraine symptom severity score (odds ratio 1.17, confidence interval 1.15, 1.19) and more severe pain intensity (odds ratio 1.11, confidence interval 1.08, 1.14); probable depression and/or anxiety (odds ratio 1.83, confidence interval 1.67, 2.00); and overuse of acute medication (odds ratio 1.23, confidence interval 1.09, 1.38). A higher number of monthly headache days increased the likelihood of allodynia, but the effect was attenuated in the fully adjusted model.

Conclusion

In a representative sample of US adults with migraine, there were significant associations between allodynia and headache frequency and intensity, anxiety and/or depression, symptom severity, and acute medication overuse.