title: The commensal bacterium Faecalibacterium prausnitzii is protective in DNBS-induced chronic moderate and severe colitis models.
abstract: BACKGROUND
  The abundance of Faecalibacterium prausnitzii, an abundant and representative bacterium of Firmicutes phylum, has consistently been observed to be lower in patients with Crohn's disease than in healthy individuals. We have shown that both F. prausnitzii and its culture supernatant (SN) have anti-inflammatory and protective effects in a TNBS-induced acute colitis mouse model. Here, we tested the effects of both F. prausnitzii and its SN in moderate and severe DNBS-induced chronic colitis mouse models.
  
  
  METHODS
  Colitis was induced by intrarectal administration of DNBS. After either 4 or 10 days of recovery (severe and moderate protocols, respectively), groups of mice were intragastrically administered either with F. prausnitzii A2-165 or with its culture SN for 7 or 10 days. Three days before being sacrificed, colitis was reactivated by administration of a lower dose of DNBS. The severity of colitis at the time of being sacrificed was assessed by weight loss and macroscopic and microscopic scores. Myeloperoxidase (MPO) activity, cytokine levels, lymphocyte populations, and changes in microbiota were studied.
  
  
  RESULTS
  Intragastric administration of either F. prausnitzii or its SN led to a significant decrease in colitis severity in both severe and moderate chronic colitis models. The lower severity of colitis was associated with down-regulation of MPO, pro-inflammatory cytokines, and T-cell levels.
  
  
  CONCLUSIONS
  We show, for the first time, protective effects of both F. prausnitzii and its SN during both the period of recovery from chronic colitis and colitis reactivation. These results provide further evidence that F. prausnitzii is an anti-inflammatory bacterium with therapeutic potential for patients with inflammatory bowel disease.
authors.affiliation: *INRA, Commensal and Probiotics-Host Interactions Laboratory, UMR 1319 Micalis, Jouy-en-Josas, France; †AgroParisTech, UMR 1319 Micalis, Jouy-en-Josas, France; ‡Farncombe Family Digestive Health Research Institute, Faculty of Health Sciences, McMaster University, Hamilton, Ontario, Canada; §Department of Gastroenterology and Nutrition, AP-HP, Hôpital Saint-Antoine and UPMC University of Paris, Paris, France; and ‖Equipe AVENIR Gut Microbiota and Immunity, INSERM U1057/UMR CNRS 7203, Université Pierre et Marie Curie 6, Paris, France.
authors.forename: Rebeca
authors.initials: R
authors.lastname: Martín
authors.forename: Florian
authors.initials: F
authors.lastname: Chain
authors.forename: Sylvie
authors.initials: S
authors.lastname: Miquel
authors.forename: Jun
authors.initials: J
authors.lastname: Lu
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Gratadoux
authors.forename: Harry
authors.initials: H
authors.lastname: Sokol
authors.forename: Elena F
authors.initials: EF
authors.lastname: Verdu
authors.forename: Premysl
authors.initials: P
authors.lastname: Bercik
authors.forename: Luis G
authors.initials: LG
authors.lastname: Bermúdez-Humarán
authors.forename: Philippe
authors.initials: P
authors.lastname: Langella
mesh_terms: D000818:Animals; D002908:Chronic Disease; D003092:Colitis / Q000139:chemically induced / Q000382:microbiology* / Q000517:prevention & control*; D004139:Dinitrofluorobenzene / Q000031:analogs & derivatives / Q000633:toxicity; D004195:Disease Models, Animal; D013294:Lactococcus lactis / Q000502:physiology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009195:Peroxidase / Q000378:metabolism; D019936:Probiotics / Q000008:administration & dosage*; D011379:Prognosis; D045857:Ruminococcus / Q000502:physiology*
chemical_list: C045305:2,4-dinitrofluorobenzene sulfonic acid; D004139:Dinitrofluorobenzene; D009195:Peroxidase