(P13-025-23) Apiaceous Vegetables Mitigated Severity of Dextran Sodium Sulfate (DSS)-Induced Colitis in Mice Consuming Westernized Diet

Objectives: A western diet is considered a putative element for colorectal cancer, the third most common cancer in the U.S. It also leads to gut dysbiosis and inflammation. We investigated whether apiaceous vegetables (API; celery, parsnip) supplemented to a background Total Western Diet (TWD) reduce the severity of DSS-induced colitis in mice.

Methods: TWD is formulated to match the average macro- and micronutrient intake and diet composition in the US based on the National Health and Nutrition Examination Survey. TWD ingredients were mixed with 21% (wet wt:wt; equivalent to a total ~1 c/d in the human diet using allometric scaling based on kcals) of fresh organically grown celery and parsnips and 42% (wet wt:wt) of the same vegetables. C57BL/6J mice (n=90) were assigned to 1 of 6 diets: 1) TWD only; 2) TWD+API21%, TWD with 10.5% celery and 10.5% parsnip; 3) TWD+API42%, TWD with 21% celery and 21% parsnip; 4) TWD+DSS, TWD with DSS treatment; 5) TWD+API21%+DSS; and 6) TWD+API42%+DSS. Mice received assigned diets for all 19 days with free access to normal drinking water unless assigned to 2% DSS in drinking water Day 12 – Day 17. Disease activity index (DAI) was assessed daily starting Day 12. On Day 20, mice were euthanized and tissues collected. Data were analyzed by ANOVA and Tukey’s multiple comparison test.

Results: There was no difference in food intake among the 6 groups or total weight gain prior to DSS. Total weight gain in mice on TWD+API21%+DSS (2.8 g) and TWD+API42%+DSS (3.0 g) were greater than TWD+DSS (0.4 g, both p< 0.001), and less than TWD+API21% and TWD+API42%, respectively (both p< 0.01). Mice on TWD+API21%+DSS or TWD+API42%+DSS had less severe DAI than TWD+DSS on each day starting Day 14 (all p< 0.001). TWD+DSS induced colon shortening (4.4 cm) vs TWD (6.4 cm, p< 0.001) which was improved with TWD+API21%+DSS (5.3 cm, p< 0.01) and TWD+API42%+DSS (5.5 cm, p< 0.001). There was no difference in colon weight among the 6 groups, however weight/length ratio of colon markedly increased on TWD+DSS (0.033) vs TWD (0.021, p< 0.001) and was improved on TWD+API21%+DSS (0.028, p< 0.05) and TWD+API42%+DSS (0.024, p< 0.01). There were no differences between TWD+API21%+DSS and TWD+API42%+DSS for any measure.

Conclusions: API intake mitigated chemically-induced colitis while consuming westernized diet warranting investigation of potential anti-inflammatory mechanisms.

Funding Sources: None