Figure 6.

Butyrate Supplementation Increases the Availability of AhR Ligands

(A) Mean clinical score of control and butyrate-supplemented ABX-treated or untreated mice; y axis shows percentage swelling in antigen-injected knee compared to control knee (cumulative n = 8 per group, one representative experiment of two experiments is shown).

(B) Bar chart shows expression of Il10 relative to β-actin in splenic B cells isolated from ABX-treated WT or untreated mice (cumulative n = 3 per group).

(C) Bar chart shows relative abundance of bacterial phyla in the stool of naive, control arthritic, or butyrate-supplemented arthritic mice (n = 4 per group).

(D) XY graph shows operational taxonomic units (OTUs) of bacterial genera in butyrate-supplemented and control arthritic mice (n = 4 per group).

(E–G) Bar charts shows levels of tryptophan, tryptamine, indole (E), L-Kynurenine, Kynurenic Acid (KYNA) (F), and 5-HIAA (G) in the stool of control arthritic WT and butyrate-supplemented arthritic mice (cumulative n = 5 per group).

Data represent mean ± SE (A, two-way ANOVA; B, one-way ANOVA; E–G, Student’s t test). See also Figure S7.