Fig. 2: IPA is able to improve intestinal epithelial barrier damage and consequently inhibit endotoxin secretion in rats fed a high-fat diet.

Six-week-old male rats were fed a high-fat diet for 8 weeks and then gavaged with IPA (20 mg/kg/day) once daily for 8 weeks. Rats were sacrificed at the end of the 16th week, and ilea were harvested. a Representative hematoxylin and eosin staining of the ilea is shown. The height of the villi (b) and the depth of the crypts (c) were measured, and the ratio of villus height to crypt depth (d) was calculated. e The plasma level of endotoxin was measured using a Limulus amebocyte lysate (LAL) chromogenic assay (n = 5). f Representative immunostaining of zonula occluden-1 (ZO-1) and occludin in the ilea is shown. g Protein levels of ZO-1 and occludin of intestinal epithelial cells in the ilea. Representative immunoblots and densitometric quantification from three rats in each group are shown. The data are presented as the mean ± SEM. n = 9–10, *P < 0.05, vs. rats fed a chow diet; ^#P < 0.05, vs. rats fed a high-fat diet