Tacrolimus coadministered with Lactobacillus plantarum 550 changed the diversity of the gut microbiome and bile acid metabolism in colitis. (A, D) Gut microbial α-diversity determined by Chao1 and Shannon indexes. (B, E) β-diversity analysis based on the NMDS and ANOSIM methods. (C, F) Relative abundance of gut bacterial composition at the phylum level. (G, H) Correlation analysis between bile acid concentrations and Lactobacillus relative abundance. (I) Relative concentration of TCDCA on a log 2 scale. (J) Correlation analysis between DAI score and TCDCA concentration. (K) The normalized expression levels of bile acid receptors among all groups. Data are presented as the mean ± SEM. *P < 0.05, **P < 0.01, ns, no significance. NMDS, nonmetric multidimensional scaling; FDR, false discovery rate; DAI, disease activity index; Con, control; DSS, dextran sulfate sodium; Tacro, 10 mg/kg tacrolimus; Lacto, Lactobacillus plantarum 550; TCDCA, taurochenodeoxycholic acid; Tgr5, Takeda G protein-coupled receptor 5; Fxr, farnesoid X receptor; Vdr, vitamin D (1,25- dihydroxyvitamin D3) receptor; Rxra, retinoid X receptor alpha; Rxrg, retinoid X receptor gamma; Rxrb, retinoid X receptor beta.