Apiaceous Vegetables Attenuated Inflammation Markers and Enriched Gut Lachnospiraceae in Mice Fed Western Diets

Abstract

Western-style diets are positively correlated with many chronic diseases, including obesity, diabetes, coronary artery disease, inflammatory disease, and colon cancer. Western-style diets are characterized by high consumption of protein, fat, sugar, salt, and low intake of fruits and vegetables. Here, we compared the effect of western-style diets (diet-induced obesity [DIO] and the Total Western Diet [TWD]) on colonic inflammation and gut microbiome, and the effects of supplementing apiaceous vegetables (API; celery and parsnip) to those diets. Mice were fed the western-style diets with or without API for 12 weeks; control mice were given the AIN-93G diet. TWD-induced inflammatory gene expression (p65, IκBα, TNF-α, IL-1β), which was reversed by API supplementation. DIO promoted p65 phosphorylation, which was suppressed by API supplementation. In microbiome analyses, α-diversity was increased by DIO but decreased by TWD, which were not restored by API. Both DIO and TWD showed distinct microbial structures, as indicated by Bray–Curtis and Jaccard β-diversity indices, compared with AIN-93G, and were distinct from each other. API supplementation led to differentiation from the DIO and TWD, except for TWD in Jaccard. Random forest analysis identified altered key taxa: [Ruminococcus]_gnavus was DIO- and TWD-specifically increased taxa, which was decreased by API supplementation, and Lachnospiraceae was enriched by API in both DIO and TWD. In conclusion, DIO and TWD both altered microbial composition in ways that could contribute to colonic inflammation. API may mitigate this inflammatory compositional shift through modulating bacterial abundance belonging to Lachnospiraceae family when supplemented to both DIO and TWD.