Fig. 3

DS showed analgesic effect by inhibiting NLRP3 inflammasome activation of spinal microglia in vivo. a The immunofluorescence of the spinal lumbar enlargement of CCI pain mice showed the co-localization of IBA-1 staining (red) and NLRP3 staining (green) in the ipsilateral glial area, and the contralateral side was not affected. b, c Western blotting analysis of microglia activation marker IBA-1 and NLRP3 inflammasome components in spinal lumbar enlargement tissue showed that DS inhibited the expression of IBA-1, NLRP3 protein, activated caspase-1 p10, and mature IL-1β p17 in a dose-dependent manner. Data are expressed as means ± SEM (n = 3 in each group). Statistical significance was determined by one-way ANOVA followed by Tukey’s post hoc analysis where ^##P < 0.01, ^###P < 0.011 vs. Sham + Saline group; ^*P < 0.05, ^**P < 0.01, ^***P < 0.001 vs. CCI + Saline group. NLRP3 inflammasome inhibitor MCC950 (d) and IL-1R antagonist (e) were injected intrathecally into CCI pain mice and the paw withdrawal threshold of their ipsilateral and contralateral paws were measured at 1h post intrathecal injection. Inhibiting the assembly and activation of NLRP3 inflammasome or block the binding of IL-1β to IL-1R can effectively increase the paw withdrawal threshold of CCI mice. Data are expressed as means ± SEM (n = 8 in each group). Statistical significance was determined by two-way ANOVA followed by Tukey’s post hoc analysis where ^**P < 0.01, ^***P < 0.001 vs. CCI + Saline group