Fig. 1

Abx pretreatment ameliorated colitis, regulated dysbiosis, relieved the dysfunction of gut microbiota, and improved colon CD4⁺T cells. The weight loss (A) and DAI scores (B) in the indicated groups. ^*P < 0.05, ^**P < 0.01, and ^***P < 0.001 compared to the DSS group; ^##P < 0.01 and ^###P < 0.001 compared to the control group; and ^&P < 0.05 compared to the Abx + DSS group. The colon length (C) and histological scores (D) are depicted with or without Abx pretreatment. (E) Representative H&E-staining figures of the colon (10× magnified in the larger frame, 40× magnified in the smaller frame; scale bar − 200 μm). (F) IL-6, TNF-α, IL-1β mRNA levels in the indicated groups. (G) Alpha-diversity in the indicated groups. (H) Unweighted UniFrac based PCoA analysis in the indicated groups. The top 10 dominant taxa among the DSS group and DSS + Abx group, for the phylum level (I) and the genus level (J), respectively. (K) The relative abundance of Akkermansia, Lactobacillus, and Clostridium_sensu_stricto_1, Bacteroides. (L) The level of SCFA in feces among groups. The frequency of T cells (M, N) and CD4⁺T cells (O, P). These results are indicated as mean ± SEM. ^*P < 0.05, ^**P < 0.01, and ^***P < 0.001 compared to the DSS group. DSS, dextran sodium sulfate; Abx, antibiotic cocktail; Abx + DSS, DSS-induced colitis model with Abx pretreatment; DAI, Disease activity index; and SCFA, short-chain fatty acid