Fig. 4: Mechanisms of FDN-mediated colon protection.

a, b Colonic mRNA expression of cyp3a11 (n = 5 for No DSS, n = 3 for DSS, n = 4 for DSS + PCN, n = 4 for DSS + FDN), mdr1a (n = 6 for No DSS, n = 6 for DSS, n = 4 for DSS + PCN, n = 5 for DSS + FDN), and cyp2b10 (n = 4 for No DSS, n = 5 for DSS, n = 5 for DSS + PCN, n = 3 for DSS + FDN) (a), and gsta (n = 6 except n = 5 for No DSS), and gstm (n = 6) (b) mRNA expression levels in wild-type mice. c Protein expression levels of p-p65, p65, p-IκBα, and IκBα in the colon measured by immunoblotting. α-Tubulin was used as the loading control. Experiments were performed in triplicate and repeated twice with similar results. d Colonic IL-6 (n = 6 mice), IL-1β (n = 6 mice except n = 5 for DSS and DSS + FDN), and TNF-α (n = 6 mice) levels. e Representative immunofluorescence images of Occludin (green) and ZO-1 (red) distributions in colon sections. n = 3 biological samples per group, the representative example shown. f Relative fluorescent intensity of Occludin and ZO-1 (n = 3 mice). a, b Data were analyzed by two-way ANOVA with multiple comparisons and are expressed as mean ± SD. d, f Data were analyzed by one-way ANOVA with multiple comparisons and are expressed as mean ± SD. p-values are in comparison to the DSS group. FDN furanodienone, PCN pregnenolone-16a carbonitrile, DSS dextran sodium sulfate. Source data are provided in the Source Data file.