Methylprednisolone blocks interleukin 1 beta induced calcitonin gene related peptide release in trigeminal ganglia cells

Abstract

Background: Methylprednisolone (MPD) is a rapid acting highly effective cluster headache preventive and also suppresses the recurrence of migraine attacks. Previously, we could demonstrate that elevated CGRP plasma levels in a cluster headache bout are normalized after a course of high dose corticosteroids. Here we assess whether MPD suppresses interleukin-1β (IL-1β)- and prostaglandin E2 (PGE2)-induced CGRP release in a cell culture model of trigeminal ganglia cells, which could account for the preventive effect in migraine and cluster headache. Metoprolol(MTP), a migraine preventive with a slow onset of action, was used for comparison.

Methods: Primary cultures of rat trigeminal ganglia were stimulated for 24 h with 10 ng/ml IL-1β or for 4 h with 10 μM PGE2 following the exposure to 10 or 100 μM MPD or 100 nM or 10 µM MTP for 45 min or 24 h. CGRP was determined by using a commercial enzyme immunoassay.

Results: MPD but not MTP blocked IL-1β-induced CGRP release from cultured trigeminal cells. PGE2-stimulated CGRP release from trigeminal ganglia cell culture was not affected by pre-stimulation whether with MPD or MTP.

Conclusion: MPD but not MTP suppresses cytokine (IL-1β)-induced CGRP release from trigeminal ganglia cells. We propose that blockade of cytokine mediated trigeminal activation may represent a potential mechanism of action that mediates the preventive effect of MTP on cluster headache and recurrent migraine attacks.

Keywords: Calcitonin gene related peptide; Cluster headache; Interleukin-1β; Methylprednisolone; Metoprolol; Migraine; Prostaglandin E2; Trigeminal ganglia cells.

Fig. 1

Pretreatment with methylprednisolone (MPD) suppressed IL-1β-stimulated CGRP release in trigeminal ganglia cell culture. Kruskal-Wallis test followed by Mann–Whitney U test with p-values adjusted for multiple comparisons using the Bonferroni-Holm method was used to determine significant differences. IL-1β (10 ng/ml) but not vehicle stimulation (PBS) resulted in significantly enhanced CGRP levels in the supernatant of cultured trigeminal ganglia cells after 24 h (*p = 0.031 vs. vehicle). Exposure to MPD 10 μM or 100 μM 45 min prior to stimulation with IL-1β blocked CGRP release significantly compared to pre-treatment with PBS (# p = 0.022 (10 μM) and p = 0.012 (100 μM). CGRP levels are shown in mean pg/ml ± SEM, n = 9

Fig. 2

Pretreatment with methylprednisolone (MPD) did not affect PGE₂-stimulated CGRP release in trigeminal ganglia cell culture. CGRP secretion was determined after pretreatment with PBS or MPD (10 μM or 100 μM) for 45 min or 24 h followed by stimulation with PGE₂ (10 μM) or vehicle for 4 h. CGRP release was significantly enhanced after PBS + PGE₂ (* p < 0.0001, compared to PBS + PBS). CGRP levels were not altered by pre-stimulation with MPD for 45 min or 24 h (p > 0.05, compared to pre-treatment with PBS). CGRP levels are shown in mean pg/ml ± SEM, n = 7–8

Fig. 3

Exposure to metoprolol (MTP) did not affect IL-1β-stimulated CGRP release in trigeminal ganglia cell culture. CGRP secretion was determined 45 min after pretreatment with MTP (100 nM and 10 μM) respectively PBS followed by a 24 h exposure to PBS or IL-1β (10 ng/ml). IL-1β stimulation for 24 h led to a significant CGRP release compared to vehicle stimulation (* p = 0.042) which was not altered by pre-treatment with MTP (100 nM or 10 μM) (p > 0.05, compared to pre-treatment with PBS). CGRP levels are shown in mean pg/ml ± SEM, n = 9

Fig. 4

Pretreatment with metoprolol (MTP) did not affect PGE₂-stimulated CGRP release in trigeminal ganglia cell culture. CGRP secretion was determined 45 min or 24 h after pretreatment with PBS, MTP 100 nM or MTP 10 μM followed by a 4 h exposure to PBS or PGE (10 μM). Stimulation with PGE₂ resulted in an induction of CGRP release (* p < 0.0001 resp. 0.015, compared to treatment with PBS), which was not altered by previous exposure to MTP (100 nM or 10 μM) (p > 0.05, compared to pre-treatment with PBS). CGRP levels are shown in mean pg/ml ± SEM, n = 9