Fusobacterium nucleatum impedes remission of colitis in a mouse model.

The role of Fusobacterium nucleatum, often associated with intestinal diseases, in remission of dextran sulfate sodium (DSS)-induced colitis was investigated. Female mice were divided into groups DC (DSS control) and DF (DSS + F.nucleatum). F.nucleatum (1.0 × 1010 cfu/mouse/day) in PBS was orally given to DF, while DC had PBS only. All mice had DSS in drinking water. In Experiment 1, mice underwent two inflammation phases, an in-between recovery phase, and had their disease activity indices (DAI) calculated. Experiment 2 was similarly conducted, except that mice were dissected 3 days post-recovery, and had blood and colonic mucosal samples collected. In Experiment 1, DF had significantly (P < .05) higher DAI than DC, during the recovery and 2nd inflammation phases. In Experiment 2, genus Bacteroides was significantly (P < .05) higher and family Lachnospiraceae significantly lower in cecal mucosa-associated microbiota of DF than in that of DC. We concluded that F.nucleatum can impeded colitis remission.