title: Chronic cigarette smoke exposure induces microbial and inflammatory shifts and mucin changes in the murine gut.
abstract: Inflammatory bowel diseases (IBD) are complex multifactorial diseases characterized by an inappropriate host response to an altered commensal microbiome and dysfunctional mucus barrier. Cigarette smoking is the best known environmental risk factor in IBD. Here, we studied the influence of chronic smoke exposure on the gut microbiome, mucus layer composition and immune factors in conventional mice. We compared smoke-exposed with air-exposed mice (n = 12) after a smoke exposure of 24 weeks. Both Illumina sequencing (n = 6) and denaturing gradient gel electrophoresis (n = 12) showed that bacterial activity and community structure were significantly altered in the colon due to smoke exposure. Interestingly, an increase of Lachnospiraceae sp. activity in the colon was observed. Also, the mRNA expression of Muc2 and Muc3 increased in the ileum, whereas Muc4 increased in the distal colon of smoke-exposed mice (n = 6). Furthermore, we observed increased Cxcl2 and decreased Ifn-γ in the ileum, and increased Il-6 and decreased Tgf-β in the proximal colon. Tight junction gene expression remained unchanged. We infer that the modulating role of chronic smoke exposure as a latently present risk factor in the gut may be driven by the altered epithelial mucus profiles and changes in microbiome composition and immune factors.
authors.affiliation: Department of Medical and Forensic Pathology, Ghent University, Ghent, Belgium.
authors.forename: Liesbeth
authors.identifier: 0000-0003-2663-8566
authors.initials: L
authors.lastname: Allais
authors.affiliation: Laboratory of Microbial Ecology and Technology (LabMET), Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium.
authors.forename: Frederiek-Maarten
authors.initials: FM
authors.lastname: Kerckhof
authors.affiliation: Department of Pathology, AZ Sint-Jan, Brugge, Belgium.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Verschuere
authors.affiliation: Laboratory for Translational Research in Obstructive Pulmonary Diseases, Department of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium.
authors.forename: Ken R
authors.initials: KR
authors.lastname: Bracke
authors.affiliation: Department of Medical and Forensic Pathology, Ghent University, Ghent, Belgium.
authors.forename: Rebecca
authors.initials: R
authors.lastname: De Smet
authors.affiliation: Department of Gastroenterology, Ghent University, Ghent, Belgium.
authors.forename: Debby
authors.initials: D
authors.lastname: Laukens
authors.affiliation: Laboratory of Microbial Ecology and Technology (LabMET), Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium.
authors.forename: Pieter
authors.initials: P
authors.lastname: Van den Abbeele
authors.affiliation: Department of Gastroenterology, Ghent University, Ghent, Belgium.
authors.forename: Martine
authors.initials: M
authors.lastname: De Vos
authors.affiliation: Laboratory of Microbial Ecology and Technology (LabMET), Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium.
authors.forename: Nico
authors.initials: N
authors.lastname: Boon
authors.affiliation: Laboratory for Translational Research in Obstructive Pulmonary Diseases, Department of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium.
authors.forename: Guy G
authors.initials: GG
authors.lastname: Brusselle
authors.affiliation: Department of Medical and Forensic Pathology, Ghent University, Ghent, Belgium.
authors.forename: Claude A
authors.initials: CA
authors.lastname: Cuvelier
authors.affiliation: Laboratory of Microbial Ecology and Technology (LabMET), Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium.
authors.forename: Tom
authors.initials: T
authors.lastname: Van de Wiele
mesh_terms: D000818:Animals; D001419:Bacteria / Q000302:isolation & purification; D003106:Colon / Q000378:metabolism / Q000382:microbiology; D004781:Environmental Exposure; D000069196:Gastrointestinal Microbiome; D041981:Gastrointestinal Tract / Q000382:microbiology; D015870:Gene Expression; D007082:Ileum / Q000378:metabolism; D018836:Inflammation Mediators / Q000378:metabolism*; D008297:Male; D008810:Mice, Inbred C57BL; D009077:Mucins / Q000235:genetics / Q000378:metabolism*; D012907:Smoking; D062789:Tobacco Products
chemical_list: D018836:Inflammation Mediators; D009077:Mucins