Astragalus polysaccharide attenuates rat experimental colitis by inducing regulatory T cells in intestinal Peyer’s patches

Figure 1 Representative images of colons and colonic character assay. A: Representative images of colons; B: Colonic length; C: Colonic weight; D: Weight index of the colon. Data are mean ± SEM (n = 8). ^bP < 0.01, ^eP < 0.001, ^fP < 0.0001 vs normal group; ^aP < 0.05 vs TNBS group. TNBS: 2,4,6-trinitrobenzene sulfonic acid; APS: Astragalus polysaccharide; MES: Mesalazine.

Figure 2 Representative histological images and injury scores. A: Representative histological images stained with HE. F1: Normal; F2: TNBS; F3: TNBS + APS; F4: TNBS + MES. Bar = 100 μm. B: Macroscopic scores. C: Histological scores. Data are mean ± SEM (n = 8). ^eP < 0.001, ^fP < 0.0001 vs Normal group; ^aP < 0.05, ^bP < 0.01, ^cP < 0.0001 vs TNBS group. TNBS: 2,4,6-trinitrobenzene sulfonic acid; APS: Astragalus polysaccharide; MES: Mesalazine.

Figure 3 Assay of Treg cells. A: Representative flow plots of CD4⁺CD25⁺Foxp3⁺ T cells. Histograms show the distribution of immunofluorescence labeling intensity of CD4, CD25 and Foxp3 expression in each group. Ordinate indicates cell counts; abscissa represents fluorescent intensity. B: Levels of CD4⁺CD25⁺Foxp3⁺ T cells. Data are mean ± SEM (n = 8). ^aP < 0.05 vs normal group; ^bP < 0.01, ^fP < 0.0001 vs TNBS group. TNBS: 2,4,6-trinitrobenzene sulfonic acid; APS: Astragalus polysaccharide; MES: Mesalazine.

Figure 4 Concentrations of cytokines in the colonic mucosa. A: Concentrations of IL-17 in the colonic mucosa from different groups; B: Concentrations of IL-2 in the colonic mucosa from different groups; C: Concentrations of IL-6 in the colonic mucosa from different groups; D: Concentrations of TGF-β in the colonic mucosa from different groups. Data are mean ± SEM (n = 8). ^aP < 0.05, ^bP < 0.01, ^eP < 0.0001 vs normal group; ^cP < 0.05, ^dP < 0.01, ^fP < 0.001, ^gP < 0.0001 vs TNBS group. TNBS: 2,4,6-trinitrobenzene sulfonic acid; APS: Astragalus polysaccharide; MES: Mesalazine.

Figure 5 Western blot analysis of IL-23, ROR-γt and STAT-5a expression. A: Representative Western blots of IL-23, ROR-γt, STAT-5 and GAPDH (n = 6); B: Quantitative analysis of ROR-γt protein (n = 6); C: Quantitative analysis of IL-23 protein (n = 6); D: Quantitative analysis of STAT-5a protein (n = 6). Data are mean ± SEM (n = 8). ^aP < 0.05, ^eP <0.000 vs normal group; ^cP < 0.05, ^bP < 0.01, ^fP < 0.001 vs TNBS group. TNBS: 2,4,6-trinitrobenzene sulfonic acid; APS: Astragalus polysaccharide; MES: Mesalazine.