Fig. 3

Transplantation of the NLRP3 KO gut microbiota ameliorated CUS-induced depressive-like behaviors. a FMT experimental design and behavioral tests. Mice were treated with antibiotics for 7 weeks and gavaged with the fecal contents of either WT or NLRP3 KO donor mice for 3 days. After 1 week of recovery, the FMT recipient mice were subjected to CUS for 4 weeks, and behavioral tests were performed before the mice were sacrificed. b Compared to WT microbiota recipient mice, NLRP3 KO microbiota recipient mice displayed an inhibition of the CUS-induced decrease in sucrose preference. c, d Compared to WT microbiota recipient mice, NLRP3 KO microbiota recipient mice displayed an inhibition of the CUS-induced increase in immobility time in the FST (c) and TST (d). N = 20 mice/group. **p < 0.01 and ***p < 0.001 vs. the FMT-WT control group. ^#p < 0.05, ^##p < 0.01 and ^###p < 0.001 vs. the CUS-treated FMT-WT group using one-way ANOVA followed by the Holm-Sidak test. e Three-dimensional PCoA of unweighted UniFrac distances showed obvious differences in the gut microbiota composition between FMT-WT and FMT-NLRP3 KO mice with/without CUS treatment. f Heatmap of the 61 discriminative OTUs among FMT-WT and FMT-NLRP3 KO mice with/without CUS treatment. Each OTU ID and taxonomic assignment is provided to the right of the heatmap. Relative abundances of the phyla present in samples from the FMT-WT control group (pink bar), CUS-treated FMT-WT group (blue bar), FMT-NLRP3 KO control group (purple bar), and CUS-treated FMT-NLRP3 KO group (green bar). g Mice transplanted with the NLRP3 KO microbiota showed an inhibition of the CUS-induced alteration in the relative abundances of genera compared to WT microbiota recipient mice. N = 12-16 mice/group. *p < 0.05, **p < 0.01 and ***p < 0.001 vs. the FMT-WT control group. ^#p < 0.05 and ^##p < 0.01 vs. the CUS-treated FMT-WT group using the Mann-Whitney test