Figure 5:
Meteorin reverses hyperalgesic priming in animals primed with IL-6. A) Quantile normalized expression of Metrn is observed to be decreased in paclitaxel-treated Nav1.8cre/Rosa26fsTRAP mice after the resolution of paclitaxel-induced pain behaviors. B) Diagram showing the dosing paradigm of IL-6, rmMTRN, and PGE2 and behavioral testing schedule. C) 1.8mg/kg rmMTRN administration an hour prior to PGE2 injection attenuated the development of mechanical hypersensitivity in IL-6-primed animals. (Two-way ANOVA, F = 24.77, p-value = <0.0001, Tukey’s multiple comparison test, Day1 post PGE2 injection, IL-6+PGE2 vs. IL-6+rmMTRN (1.8 mg/kg)+PGE2, p-value = <0.0023, Day2 post PGE2 injection, IL-6+PGE2 vs. IL-6+rmMTRN (1.8 mg/kg)+PGE2, p-value = < 0.0001, IL-6+PGE2, N=4, Veh+PGE2, N=5, IL-6+rmMTRN (1.8 mg/kg)+PGE2, N=6). D) Effect size was calculated from the first administration of rmMTRN and was observed to be significant between primed animals treated with PGE2 and primed animals administered with rmMTRN and PGE2. (One-way ANOVA, IL-6+PGE2 : IL-6+rmMTRN (1.8 mg/kg)+ PGE2, p-value = <0.0079, IL-6+PGE2 : Vehicle+PGE2, p-value = <0.0124) E) Grimacing behavior was observed to be similar to its baseline measurements in mice administered with rmMTRN (Two-way ANOVA, F = 10.35, p-value = <0.0001, Day1 post PGE2 injection, IL-6+PGE2 vs. Baseline measurement, p-value = 0.0302, Day2, IL-6+PGE2 vs. Baseline measurement, p-value = 0.0256, Day1 post PGE2 injection, IL-6+rmMTRN (1.8 mg/kg)+PGE2 vs. Baseline measurement of IL-6+ rmMTRN (1.8 mg/kg), p-value = 0.4465, Day2, IL-6+rmMTRN (1.8 mg/kg)+PGE2 vs. Baseline measurement of IL-6+rmMTRN (1.8 mg/kg), p-value = 0.9167).