Fig. 4. MDP mediate the colitis protective effects of LPH.

a–e The protective effects of LPH or its active site mutants (5 mg/kg body weight) on TNBS-induced colitis: body weight loss (a); colon length (b); serum FITC-dextran levels (c); representative H&E staining of colonic tissue, scale bar, 100 μm (d) and the semiquantitative scoring of inflammation (e) of mice pre-treated with LPH or its different mutants. f–i Mice were gavaged with pectin/zein beads containing BSA (5 mg/kg body weight) or indicated dosage of LPH (mg/kg body weight), and the ability of colonic homogenate (f), ileal homogenate (g), fecal extract (h) or serum (i) to activate NOD2-expressing NF-κB reporter HEK293 cells were detected. Data are presented as fold change relative to BSA treated group (control). j–m Mice were gavaged with pectin/zein beads containing LPH mutants at a dosage of 1 mg/kg or 5 mg/kg body weight as indicated. The ability of colonic homogenate (j), ileal homogenate (k), fecal extract (l), or serum (m) to activate NOD2-expressing NF-κB reporter HEK293 cells were detected. Data are presented as fold change relative to BSA treated group (control). BSA: bovine serum albumin; LPH-AS1: the D316A mutation of LPH; LPH-AS2: the D329A mutation of LPH; LPH-AS3: P295A, G297A, and T298A mutations of LPH. Data are representative of 3 independent experiments and presented as mean ± SD. Each dot indicates an individual mouse (n = 6, female). Statistical analyses were performed using repeated measures ANOVA with Bonferroni post hoc test (a), one-way ANOVA with Bonferroni post hoc test (b, c, e, f–m). Source data are provided as a Source data file.