Fig. 5

Maresin 1 alleviated nerve injury-induced neuropathic pain. Intrathecal injection of MaR1 attenuated the mechanical allodynia (A) and thermal hyperalgesia (B) induced by SCI. The data are presented as the mean ± SD, n = 6 mice in each group, *p < 0.05 versus the BL group; ^#p < 0.05 versus the 10 ng MaR1 group, two-way ANOVA and Bonferroni post hoc test. C MaR1 inhibited capsaicin (CAP; 100 nM)-induced inward currents. The data are presented as the mean ± SD, n = 9 neurons, *p < 0.05 versus the control group, Student’s t-test. D–F MaR1 suppressed the activation of astrocytes (immunofluorescence staining of GFAP) and microglia (immunofluorescence staining of IBA-1) in the L4–L6 spinal dorsal horn at 7 days after sciatic nerve crush injury by double immunohistochemistry analysis. *p < 0.05 versus the contralateral group; ^#p < 0.05 versus the vehicle group, Student’s t-test, two-way ANOVA and Bonferroni post hoc test. Intensity of staining was qualified by ImageJ. Four fluorescence positive arbitrary units were randomly selected and calculated the intensity of staining with background subtraction by analyze-measure function of ImageJ. G qRT-PCR indicated that MaR1 inhibited the increased mRNA expression of Il1β, Il6, and TNF-a in the ipsilateral L4–L6 region induced by sciatic nerve crush injury at 7 days after the treatment. The data are presented as the mean ± SD, n = 4 mice in each group. *p < 0.05 versus the contralateral group; ^#p < 0.05 versus the vehicle group, Student’s t-test, two-way ANOVA and Bonferroni post hoc test