Fig. 5.

Diet-, binge-, and time-dependent effects on markers of intestinal barrier integrity in Nanji diet-fed mice. Mice were fed a Nanji diet for 4 wk, and during the 5th wk (i.e., days 43–45) mice were administered a once/daily binge of alcohol (6 g/kg) or the vehicle control for alcohol (i.e., PBS) at a specific time indicated by the zeitgeber time (ZT); mice were given a test for intestinal permeability immediately following the 2nd binge; and mice were euthanized 4 h after the 3rd and final once/daily binge. Intestinal barrier integrity and liver pathology were assessed. A–C: intestinal barrier integrity was evaluated following the bolus administration of a sugar solution, and urinary sugar was measured as an index of barrier integrity; higher urinary sugar equates to greater barrier dysfunction. A: urinary lactulose exhibited a significant effect of binge (binge: P < 0.00). Post hoc Tukey’s test revealed significant time-of-day effects. B: urinary mannitol exhibited a significant effect of binge (binge: P < 0.00). Post hoc Tukey’s test revealed no significant effects. C: urinary sucralose revealed a significant effect of binge (P < 0.00) as well as a binge × time interaction (P = 0.01). Post hoc Tukey’s test revealed significant time-of-day effects. D and E: intestinal barrier integrity was also evaluated using serum markers, including lipopolysaccharide (LPS) and lipopolysaccharide-binding protein (LBP). D: serum LPS exhibited a significant effect of diet (P = 0.03), binge (P = 0.01), and time (P < 0.00) as well as a diet × time interaction (P < 0.00), a binge × time interaction (P < 0.00), and a diet × binge × time interaction (P = 0.02). Post hoc analysis revealed significant time-of-day effects. E: serum LBP levels were unaffected by binge or time. Between n = 5 and 10 were mice were included in each treatment group at each time point. Three-way ANOVA followed by post hoc Tukey’s test (*P < 0.05; **P < 0.01; ***P < 0.001) was used for all analyses.