The place of corticosteroids in migraine attack management: A 65-year systematic review with pooled analysis and critical appraisal.

BACKGROUND AND OBJECTIVES: Headaches recur in up to 87% of migraine patients visiting the emergency department (ED), making ED recidivism a management challenge. We aimed herein to determine the role of corticosteroids in the acute management of migraine in the ED and outpatient care. METHODS: Advanced search strategies employing PubMed/MEDLINE, Web of Science, and Cochrane Library databases inclusive of a relevant gray literature search was employed for Clinical Studies and Systematic Reviews by combining the terms "migraine" and "corticosteroids" spanning all previous years since the production of synthetic corticosteroids ca. 1950 until August 30, 2014. Methods were in accordance with MOOSE guidelines. RESULTS: Twenty-five studies (n = 3989, median age 37.5 years, interquartile range or IQR 35-41 years; median male:female ratio 1:4.23, IQR 1:2.1-6.14; 52% ED-based, 56% randomized-controlled) and four systematic reviews were included. International Classification of Headache Disorders criteria were applied in 64%. Nineteen studies (76%) indicated observed outcome differences favoring benefits of corticosteroids, while six (24%) studies indicated non-inferior outcomes for corticosteroids. Median absolute risk reduction was 30% (range 6%-48.2%), and 11% (6%-48.6%) for 24-, and 72-hour headache recurrence, respectively. Parenteral dexamethasone was the most commonly (56%) administered steroid, at a median single dose of 10 mg (range 4-24 mg). All meta-analyses revealed efficacy of adjuvant corticosteroids to various abortive medications-indicating generalizability. Adverse effects were tolerable. Higher disability, status migrainosus, incomplete pain relief, and previous history of headache recurrence predicted outcome favorability. CONCLUSIONS: Our literature review suggests that with corticosteroid treatment, recurrent headaches become milder than pretreated headaches and later respond to nonsteroidal therapy. Single-dose intravenous dexamethasone is a reasonable option for managing resistant, severe, or prolonged migraine attacks.

Expression of ASIC3 in the Trigeminal Nucleus Caudalis Plays a Role in a Rat Model of Recurrent Migraine.

Acid-sensing ion channel 3 (ASIC3) is abundant in the trigeminal nervous system and is most sensitive to a slight pH decrease. Recent studies have indicated that ASIC3 in the peripheral trigeminal ganglia is likely involved in the pathogenesis of migraine pain. However, it is unclear whether this receptor plays a role in recurrent migraine, namely, migraine chronicity. Here, we aimed to investigate the role of ASIC3 in an animal model of recurrent migraine (RM). In this study, we established a rat model of RM through repeated administration of inflammatory soup (IS) onto the dura. Then, we tested the mechanical pain thresholds of the face and hindpaws by von Frey filaments. qRT-PCR, Western blot and immunofluorescence labelling were used to detect the expression and localization of ASIC3 in the trigeminal nucleus caudalis (TNC). The protein levels of calcitonin gene-related peptide (CGRP), its receptor component receptor activity modifying protein 1 (RAMP1) and c-Fos were analysed following treatment with the ASIC3 inhibitor APETx2 and activator 2-guanidine-4-methylquinazoline (GMQ). We found decreased pain thresholds after repeated dural inflammatory stimulation, which suggested the establishment of an RM model. Based on this model, we observed elevated expression of ASIC3 in the TNC group compared to that in the Sham group. ASIC3 was primarily expressed in neurons but not in astrocytes of the TNC. Moreover, APETx2 attenuated tactile allodynia and significantly decreased the expression of c-Fos, CGRP and RAMP1, while GMQ aggravated these effects compared to those observed in the IS + vehicle group. These findings indicate a critical role of ASIC3 channels in the pathophysiology of RM, and ASIC3 might represent a potential therapeutic target to prevent the progression of migraine.

PTEN inhibition preserves trigeminal nucleus caudalis neuron activation through tyrosine phosphorylation of the NR2B subunit at Tyr1472 of the NMDA receptor in a rat model of recurrent migraine.

OBJECTIVE: Activation of the trigeminal nucleus caudalis is believed to be involved in the pathomechanism of migraine. Evidence suggests that N-methyl-d-aspartate receptor subtype 2B tyrosine phosphorylation, originating from the trigeminal nucleus caudalis neuron dysfunction, might be a triggering mechanism for recurrent migraine. Phosphatase and tensin homolog is thought to have a neuroprotective effect in various neurologic diseases by regulating N-methyl-d-aspartate receptor subtype 2B or tyrosine phosphorylation. Thus, the aim of this study was to explore whether the recombinant adenovirus AdR-siPTEN attenuates neuron activation in the trigeminal nucleus caudalis in a rat model of recurrent migraine. METHODS: Adenovirus-expressing siPTEN or RFP was independently injected into the spinal trigeminal nucleus of the rat model suffering from recurrent migraine by inflammatory soup stimulation the superior sagittal sinus of rats. Seven days later, tactile sensory testing was performed to detect the tactile threshold. Immunofluorescence, Immunohistochemistry, and western blot assay were done to measure PTEN, NR2B, NR2B-pTyr1472, and c-Fos levels in the trigeminal nucleus caudalis of recurrent migraine rats. RESULTS: A significant increase (p < 0.05) in neuron c-Fos content, an indicator of neuron activation, was detected in the trigeminal nucleus caudalis in a rat model of recurrent migraine. However, neuron activation in the trigeminal nucleus caudalis was attenuated by pretreatment with AdR-siPTEN. Moreover, the attenuated effect was potentially mediated by tyrosine phosphorylation of the NR2B-p1472 tyrosine site in the trigeminal nucleus caudalis, as seen in rat brain slices. CONCLUSION: These results suggest that, phosphatase and tensin homolog might be a novel and promising candidate for future treatment or prophylaxis of recurrent migraine by attenuating neuron activation in the trigeminal nucleus caudalis.