Fig. 4

hUMSCs downregulated the NLRP3/Caspase-1/GSDMD signaling pathway and reduced microglia pyroptosis in TBI mice via TSG-6. TBI mice were intracerebroventricularly injected with 10 μL of PBS, 0.5 µg rmTSG-6 or 1 µg rmTSG-6, or 2.5 × 10⁵ hUMSCs, sh-TSG-6 hUMSCs, sh-NC hUMSCs, in 10 μL of PBS at 4 h after TBI surgery. Then TBI mice were sacrificed and brain tissues were removed at 48 h post-TBI surgery. a Representative protein bands and corresponding grayscale values of NLRP3, pro-Caspase-1, Caspase-1 p20, GSDMD, and cleaved-GSDMD performed by western blotting. b–d Representative double immunofluorescence staining photographs and quantification of Iba-1 (green) with NLRP3 (red), Caspase-1 p20 (red), or GSDMD (red) in the injured cortex. Scale bar = 50 μm. All data are represented as means ± SD (n = 6 mice/group) and compared by one-way ANOVA, followed by the Tukey’s post hoc test. *p < 0.05, **p < 0.01, versus TBI group; ^#p < 0.05, sh-TSG-6 hUMSC group versus sh-NC hUMSC group