Abstract
Objectives
Cruciferous (CRU; rich in glucosinolates) and apiaceous (API; rich in furanocoumarins) vegetable intake decrease colon cancer risk markers, likely through different mechanisms. Previous reports suggest background diets influence efficacy of bioactives. Here, we determined the effects on the composition of the gut microbiome of CRU and API supplementation to different background diets, diet-induced obesity (DIO) and the total western diet (TWD).
Methods
C57BL/6J male mice were fed standard diet (AIN93G), DIO, DIO with 21% (w/w) CRU (DIO + CRU), DIO with 21% (w/w) API (DIO + API), TWD, TWD with CRU (TWD + CRU), or TWD with API (TWD + API). After 12 weeks, cecal contents were collected for 16S rRNA sequencing and data analyzed by mothur.
Results
There were no differences in body weight gain except mice fed DIO + CRU gained more than mice fed AIN-93G or TWD. Lachnospiraceae was increased by CRU supplementation to both DIO and TWD and by API supplementation to TWD. CRU increased alpha diversity [Shannon Index, number of observed Operational Taxonomic Unit (OTUs)] compared to DIO and TWD. Regarding beta diversity, DIO + CRU showed distinct cluster compared to DIO (Bray-Curtis, ANOSIM, R = 0.35, P < 0.001; Jaccard distance, R = 0.47, P < 0.001). TWD + CRU showed distinct cluster compared to TWD (Bray-Curtis, R = 0.59, P < 0.001; Jaccard distance, R = 0.62, P < 0.001). API did not change alpha diversity, but did affect beta diversities with distinct clusters between API groups and their basal diet groups (Jaccard distance, R = 0.36 and 0.31 for DIO and TWD, respectively, P < 0.05). Among top 25 discriminating features between DIO and TWD and their supplementation of API and CRU, there were 9 shared OTUs including Lachnospiraceae, Clostridium XlVa, Clostridiales, Eisenbergiella, and Clostridium IV. Akkermansia were decreased in DIO + CRU compared with DIO. In TWD panel, Bifidobacterium and Erysipelotrichaceae decreased in TWD + CRU, while Turicibacter were identified as TWD + CRU signature. Erysipelotrichaceae and Bifidobacterium differentiated AIN-93G, DIO, and TWD.
Conclusions
CRU supplementation of DIO and TWD altered gut microbiome composition with some differences based on background diet. API also altered composition, albeit to a lesser extent.
Funding Sources
University of Arkansas, Fulbright Nicaragua Fellow.