Fig. 3.

SB reduces the permeability and maintains proper tight junctions and mucin-2 in TNBS-induced mice.

All mice were pre-treated with SB for 6 weeks, and then treated with TNBS for 2 days. (A) Relative permeability of TNBS and SB treatment in WT and GPR109a^−/− mice. After treating with SB and TNBS, the mice were starved for 4 h and then gavaged with FITC-dextran (0.6 mg/g body weight at a concentration of 125 mg/mL). Serum from blood collected after 4 h was used to measure the permeability (n = 4). (B) Immunofluorescence staining of Muc2 in the colon; magnification shown is 10 ×, and the scale bar represents 300 μm (n = 4). (C-E) Expression of the tight junction encoding genes Cldn1, Ocln, and Zo1 in the colon tissue homogenate of TNBS- and SB-treated WT and GPR109a^−/− mice (n = 4).