Sweet food improves chronic stress-induced irritable bowel syndrome-like symptoms in rats

Figure 1 Time-dependent changes of sweet food consumption in normal rats for 12 d. The percentage of sweet food consumption decreased to below 50% 8 d after sweet food feeding.

Figure 2 Time-dependent changes of body weight (A), food consumption (B), caloric efficiency (C), and consumption rate of sweet food (D) in each group for 6 wk. There were significant differences in body weight between control and treated groups. Total food consumption and caloric intake were significantly reduced in the chronic variable stress-B (CVS-B) group only. Denotes significant differences among groups based on one-way analysis of variance and the Bonferroni test (^aP < 0.05 vs other groups).

Figure 3 Accumulated fecal pellet output in the chronic variable stress-A and chronic variable stress-B groups. There was no significant difference in the first week, but accumulated fecal output difference gradually increased with time. Statistical analysis was performed using repeated measures ANOVA and unpaired t test in each week between groups (^aP < 0.05 vs chronic variable stress (CVS)-B group).

Figure 4 Relative weight of the adrenal gland (A), plasma corticosterone levels (B), ACTH levels (C), and the ratio of corticosterone/ACTH following the 6-wk stress experiment. Denotes significant difference between control and other groups (^aP < 0.05 vs control groups). There was a significant difference in plasma corticosterone and adrenocorticotropic hormone (ACTH) concentrations between CON and the other groups. Denotes significant difference between chronic variable stress (CVS)-A and CVS-B group (^cP < 0.05 vs CVS-A groups). There was a significant difference in plasma corticosterone and ACTH concentration between CVS-A and CVS-B groups. CVS: Chronic variable stress.

Figure 5 Inflammatory cytokine expressions in the plasma and in the distal colon by western blot analysis following the 6 wk stress experiment. Note the prominent expressions of interleukin-2 (IL-2) and interferon-γ (IFN-γ) in the distal colon and in the plasma in the chronic variable stress (CVS)-A group only. ^aDenotes significant difference between control and other groups (^aP < 0.05). There was a significant difference in the relative density of IL-2 and IFN-γ in the plasma and distal colon between CON and the other groups. ^bDenotes significant difference between CVS-A and CVS-B group (^cP < 0.05 vs CVS-A groups). There was also a significant difference in the relative density of IL-2 and IFN-γ in the plasma and distal colon between CVS-A and CVS-B groups.