Protein Synthesis is Necessary for Priming in Preclinical Models of Migraine

Background: Migraine attacks are often triggered by normally innocuous stimuli, suggesting that sensitization within the nervous system is present. One mechanism that may contribute to neuronal sensitization in this context is translation regulation of new protein synthesis. The goal of this study was to determine whether protein synthesis contributes to behavioral responses and priming in preclinical models of migraine.

Methods: Mice received a dural injection of interleukin-6 in the absence or presence of the protein synthesis inhibitor anisomycin or the translation initiation inhibitor 4EGI-1 and were tested for facial hypersensitivity. Upon returning to baseline, mice were given a second, non-noxious dural injection of pH 7.0 to test for priming. Additionally, mice lacking phosphorylation of mRNA cap-binding protein eIF4E received dural interleukin-6 or were subjected to repeated restraint stress and then tested for facial hypersensitivity. After returning to baseline, mice were given either dural pH 7.0 or a systemic sub-threshold dose of the nitric oxide donor sodium nitroprusside and tested for priming.

Results: Dural injection of interleukin-6 in the presence of anisomycin or 4EGI-1 or in mice resulted in the partial attenuation of acute facial hypersensitivity and complete block of hyperalgesic priming. Additionally, hyperalgesic priming following repeated restraint stress was blocked in mice.

Conclusions: These studies show that protein synthesis regulated by activity-dependent translation is critical to the development of priming in two preclinical models of migraine. This suggests that targeting the regulation of protein synthesis may be a novel approach for new migraine treatment strategies.