The effect of pituitary adenylate cyclase-activating peptide-38 and vasoactive intestinal peptide in cluster headache.

BACKGROUND: Previously reported increases in serum levels of vasodilating neuropeptides pituitary adenylate cyclase-activating peptide-38 (PACAP38) and vasoactive intestinal peptide (VIP) during attacks of cluster headache could indicate their involvement in cluster headache attack initiation. We investigated the attack-inducing effects of PACAP38 and vasoactive intestinal peptide in cluster headache, hypothesising that PACAP38, but not vasoactive intestinal peptide, would induce cluster-like attacks in episodic active phase and chronic cluster headache patients. METHODS: In a double-blind crossover study, 14 episodic cluster headache patients in active phase, 15 episodic cluster headache patients in remission phase and 15 chronic cluster headache patients were randomly allocated to receive intravenous infusion of PACAP38 (10 pmol/kg/min) or vasoactive intestinal peptide (8 pmol/kg/min) over 20 min on two study days separated by at least 7 days. We recorded headache intensity, incidence of cluster-like attacks, cranial autonomic symptoms and vital signs using a questionnaire (0-90 min). RESULTS: In episodic cluster headache active phase, PACAP38 induced cluster-like attacks in 6/14 patients and vasoactive intestinal peptide induced cluster-like attacks in 5/14 patients (p = 1.000). In chronic cluster headache, PACAP38 and vasoactive intestinal peptide both induced cluster-like attacks in 7/15 patients (p = 0.765). In episodic cluster headache remission phase, neither PACAP38 nor vasoactive intestinal peptide induced cluster-like attacks. CONCLUSIONS: Contrary to our hypothesis, attack induction was lower than expected and roughly equal by PACAP38 and vasoactive intestinal peptide in episodic active phase and chronic cluster headache patients, which contradicts the PAC1-receptor as being solely responsible for attack induction.Trial registration: clinicaltrials.gov (identifier NCT03814226).

S100B and NSE in Cluster Headache - Evidence for Glial Cell Activation?

OBJECTIVE: Neuronal-specific enolase (NSE) and protein S100B have gained considerable interest as the markers of CNS injury, glial cell activation, and/or blood-brain barrier (BBB) disruption. No studies have investigated NSE and S100B in cluster headache (CH), but these biomarkers could contribute to the understanding of CH. METHODS: Patients with episodic CH in bout (eCHa), in remission (eCHr), and chronic CH (cCH) were included in this randomized, double-blind, placebo-controlled, 2-way cross-over provocation study carried out at the Danish Headache Center. The primary endpoints included (1) differences of NSE and S100B in between groups (eCHa, eCHr, and cCH) at baseline; (2) differences over time in plasma concentrations of NSE and S100B between patient developing an attack and those who did not; (3) differences in plasma concentrations over time of NSE and S100B between active day and placebo day. Baseline findings were compared to the historical data on migraine patients and healthy controls and presented with means ± SD. RESULTS: Nine eCHa, 9 eCHr, and 13 cCH patients completed the study and blood samples from 11 CGRP-induced CH attacks were obtained. There were no differences in NSE levels between CH groups at baseline, but CH patients in active disease phase had higher levels compared with 32 migraine patients (9.1 ± 2.2 µg/L vs 6.0 ± 2.2 µg/L, P < .0001) and 6 healthy controls (9.1 ± 2.2 µg/L vs 7.3 ± 2.0 µg/L, P = .007). CGRP-infusion caused no NSE changes and, but a slight, non-significant, increase in NSE was seen in patients who reported a CGRP-induced CH attack (2.39 µg/L, 95% Cl [-0.26, 3.85], P = .061). At baseline S100B levels in eCHa patients were higher compared to cCH patients (0.06 ± 0.02 µg/L vs 0.04 ± 0.02 µg/L, P = .018). Infusion of CGRP and CGRP-induced attacks did not change S100B levels. Apart from induced CH-attacks no other adverse events were noted. CONCLUSIONS: At baseline eCHa patients had higher S100B plasma levels than cCH patients and there was a slight, however not significant, NSE increase in response to CGRP-induced CH attack. Our findings suggest a possible role of an ictal activation of glial cells in CH pathophysiology, but further studies are warranted.

Calcitonin-gene related peptide and disease activity in cluster headache.

OBJECTIVE: To investigate the role of calcitonin gene-related peptide, pituitary adenylate cyclase-activating polypeptide-38 (PACAP38) and vasoactive intestinal polypeptide in cluster headache, we measured these vasoactive peptides interictally and during experimentally induced cluster headache attacks. METHODS: We included patients with episodic cluster headache in an active phase (n = 9), episodic cluster headache patients in remission (n = 9) and patients with chronic cluster headache (n = 13). Cluster headache attacks were induced by infusion of calcitonin gene-related peptide (1.5 µg/min) in a randomized, double-blind, placebo controlled, two-way cross-over study. At baseline, we collected interictal blood samples from all patients and during 11 calcitonin gene-related peptide-induced cluster headache attacks. RESULTS: At baseline, episodic cluster headache patients in remission had higher plasma levels of calcitonin gene-related peptide, 100.6 ± 36.3 pmol/l, compared to chronic cluster headache patients, 65.9 ± 30.5 pmol/l, ( p = 0.011). Episodic cluster headache patients in active phase had higher PACAP38 levels, 4.0 ± 0.8 pmol/l, compared to chronic cluster headache patients, 3.3 ± 0.7 pmol/l, ( p = 0.033). Baseline levels of vasoactive intestinal polypeptide did not differ between cluster headache groups. We found no attack-related increase in calcitonin gene-related peptide, PACAP38 or vasoactive intestinal polypeptide levels during calcitonin gene-related peptide-induced cluster headache attacks. CONCLUSIONS: This study suggests that cluster headache disease activity is associated with alterations of calcitonin gene-related peptide expression. Future studies should investigate the potential of using calcitonin gene-related peptide measurements in monitoring of disease state and predicting response to preventive treatments, including response to anti-calcitonin gene-related peptide monoclonal antibodies.

Effect of Infusion of Calcitonin Gene-Related Peptide on Cluster Headache Attacks: A Randomized Clinical Trial.

Importance: Signaling molecule calcitonin gene-related peptide (CGRP) induces migraine attacks and anti-CGRP medications abort and prevent migraine attacks. Whether CGRP provokes cluster headache attacks is unknown. Objective: To determine whether CGRP induces cluster headache attacks in episodic cluster headache in active phase, episodic cluster headache in remission phase, and chronic cluster headache. Design, Setting, and Participants: A randomized, double-blind, placebo-controlled, 2-way crossover study set at the Danish Headache Center, Rigshospitalet Glostrup, in Denmark. Analyses were intent to treat. Inclusion took place from December 2015 to April 2017. Inclusion criteria were diagnosis of episodic/chronic cluster headache, patients aged 18 to 65 years, and safe contraception in women. Exclusion criteria were a history of other primary headache (except episodic tension-type headache <5 days/mo), individuals who were pregnant or nursing; cardiovascular, cerebrovascular, or psychiatric disease; and drug misuse. Interventions: Thirty-seven patients with cluster headaches received intravenous infusion of 1.5 µg/min of CGRP or placebo over 20 minutes on 2 study days. Main Outcomes and Measures: Difference in incidence of cluster headache-like attacks, difference in area under the curve (AUC) for headache intensity scores (0 to 90 minutes), and difference in time to peak headache between CGRP and placebo in the 3 groups. Results: Of 91 patients assessed for eligibility, 32 patients (35.2%) were included in the analysis. The mean (SD) age was 36 (10.7) years (range, 19-60 years), and the mean weight was 78 kg (range, 53-100 kg). Twenty-seven men (84.4%) completed the study. Calcitonin gene-related peptide induced cluster headache attacks in 8 of 9 patients in the active phase (mean, 89%; 95% CI, 63-100) compared with 1 of 9 in the placebo group (mean, 11%; 95% CI, 0-37) (P = .05). In the remission phase, no patients with episodic cluster headaches reported attacks after CGRP or placebo. Calcitonin gene-related peptide-induced attacks occurred in 7 of 14 patients with chronic cluster headaches (mean, 50%; 95% CI, 20-80) compared with none after placebo (P = .02). In patients with episodic active phase, the mean AUC from 0 to 90 minutes for CGRP was 1.903 (95% CI, 0.842-2.965), and the mean AUC from 0 to 90 minutes for the placebo group was 0.343 (95% CI, 0-0.867) (P = .04). In patients with chronic cluster headache, the mean AUC from 0 to 90 minutes for CGRP was 1.214 (95% CI, 0.395-2.033), and the mean AUC from 0 to 90 minutes for the placebo group was 0.036 (95% CI, 0-0.114) (P = .01). In the remission phase, the mean AUC from 0 to 90 minutes for CGRP was 0.187 (95% CI, 0-0.571), and the mean AUC from 0 to 90 minutes for placebo was 0.019 (95% CI, 0-0.062) (P > .99). Conclusions and Relevance: Calcitonin gene-related peptide provokes cluster headache attacks in active-phase episodic cluster headache and chronic cluster headache but not in remission-phase episodic cluster headache. These results suggest anti-CGRP drugs may be effective in cluster headache management. Trial Registration: ClinicalTrials.gov (NCT02466334).