Protective Effect of Apiaceous Vegetables against Total Western Diet- and Dextran Sulfate Sodium-Induced Colitis in Mice.

BACKGROUND

Western-style dietary patterns are associated with colitis and colon cancer. Existing data indicate that intake of apiaceous (API) vegetables (e.g., celery, parsnip) may prevent inflammation-associated diseases.

OBJECTIVES

We investigated in mice the effect of API supplementation to the total Western diet (TWD) against dextran sulfate sodium-induced colitis.

METHODS

Male C57BL/6J mice (8-wk-old; 15 per group) were fed TWD supplemented with 21% or 42% fresh API (wt/wt) and given 2% dextran sulfate sodium to induce colitis. Diet intake, body weight, and disease activity index were monitored. Serum was collected for cytokine/chemokine analysis and colonic tissues for histology and Western blot. Fecal samples were analyzed by 16S ribosomal ribonucleic acid gene sequencing and targeted/untargeted metabolomics. Phenotypic data were analyzed by analysis of variance with Tukey's test. Microbiome data were centered log-ratio (CLR) transformed and analyzed using linear mixed models with adjusted pairwise comparisons.

RESULTS

API supplementation attenuated colitis phenotypes including weight loss (44% recovery; P < 0.001), colon shortening (57% recovery; P < 0.01), disease activity (59% lower; P < 0.001), cytokine/chemokine release (35%‒73% reductions; P < 0.05), and mucosal F4/80+ cells infiltration (80% reduction; P < 0.001). API also improved gut microbiota diversity and composition, increasing α diversity metrics (4.4%‒13.8%; P < 0.05), suppressing pathogenic bacteria (Paraclostridium, Enterococcus, Eubacterium; estimated CLR difference: -1.8 to -6.7; P < 0.001), and enriching beneficial bacteria (Lachnospiraceae and Blautia; estimated CLR difference: +1.6 to +3.0; P < 0.05). Furthermore, metabolomics indicated TWD consumption increased arachidonic acid and aliphatic aldehydes (by 109%‒510%; P < 0.001), and decreased short-chain and unsaturated fatty acids (by 30%‒91%; P < 0.001). API supplementation also mitigated TWD-derived functional metabolites (including bile acids; P < 0.05).

CONCLUSIONS

These data indicate that API intake is beneficial for risk reduction of diseases associated with Western diets. However, further investigations are warranted to determine the mechanism behind these beneficial effects.