title: Cytokine expression in gingival and intestinal tissues of patients with periodontitis and inflammatory bowel disease: An exploratory study.
abstract: OBJECTIVE
  To evaluate the expression of the cytokines IFN-γ, IL-1β, IL-4, IL-6, IL-10, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, IL-17A, IL-17F, sCD40L, and TNF-α in gingival tissue and intestinal mucosa of patients having both periodontitis and inflammatory bowel disease (IBD) and assess how they cluster in both tissues.
  
  
  METHODS
  This cross-sectional study selected 28 patients with periodontitis (18 with Crohn's disease and 10 with ulcerative colitis) from the IBD gastroenterology outpatient clinic at the Pedro Ernesto University Hospital. Patients were assessed using questionnaire, medical chart check and periodontal examination. Gingival and intestinal biopsies were collected and homogenized using a cell disruptor. Cytokines expression was evaluated through multiplex technology. Cluster analysis was performed based on cytokinés correlation strength and presented in dendrograms.
  
  
  RESULTS
  Crohn's disease and ulcerative colitis patients exhibited no significant difference between them in cytokine levels (p>0.05), so they were analysed together. Significantly higher levels of IL-17A, IL-17F, IL-22, IL-25, IL-33, IL-10, and INF-γ were found in gingival tissues in comparison with intestinal mucosa (p<0.05). In gingival tissue, cytokines formed the following clusters: IL-25/IL-10/IL-33 (r=0.775), IL-22/IL-23/IL-6 (r=0.681) and IL-6/IL-25/IL-33/IL-10 (r=0.660). In intestinal mucosa, the following clusters were formed: IL-6/IL-21/IL-10 (r=0.880), IL-17A/IL-6/IL-21/IL-10 (r=0.826), IL-I7F/IL-33/IL-25 (r=0.813) and IL-23/IL-2/IL-17A/IL-6/IL-21/IL-10 (r=0.785).
  
  
  CONCLUSIONS
  Expression of IL-17A, IL-17F, IL-22, IL-25, IL-33, IL-10, and INF-γ was significantly increased in gingival tissue in comparison with intestinal mucosa of patients with periodontitis and IBD. The cytokine clustering pattern was different in gingival and intestinal tissues.
authors.affiliation: Department of Periodontology, Faculty of Odontology, Rio de Janeiro State University, Brazil.
authors.forename: Juliana Santos Bittencourt
authors.initials: JS
authors.lastname: Menegat
authors.affiliation: Department of Periodontology, Faculty of Odontology, Rio de Janeiro State University, Brazil.
authors.forename: Ronaldo
authors.initials: R
authors.lastname: Lira-Junior
authors.affiliation: Department of Periodontology, Faculty of Odontology, Rio de Janeiro State University, Brazil; Department of Periodontology, Faculty of Odontology, Veiga de Almeida University, Brazil.
authors.forename: Mariana Alves
authors.initials: MA
authors.lastname: Siqueira
authors.affiliation: Department of Periodontology, Faculty of Odontology, Rio de Janeiro State University, Brazil.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Brito
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, Rio de Janeiro State University, Brazil.
authors.forename: Ana Teresa
authors.initials: AT
authors.lastname: Carvalho
authors.affiliation: Department of Periodontology, Faculty of Odontology, Rio de Janeiro State University, Brazil.
authors.forename: Ricardo Guimarães
authors.initials: RG
authors.lastname: Fischer
authors.affiliation: Department of Periodontology, Faculty of Odontology, Rio de Janeiro State University, Brazil. Electronic address: cmfigueredo@hotmail.com.
authors.forename: Carlos Marcelo
authors.initials: CM
authors.lastname: Figueredo
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D003093:Colitis, Ulcerative / Q000276:immunology / Q000378:metabolism; D003424:Crohn Disease / Q000276:immunology / Q000378:metabolism; D003430:Cross-Sectional Studies; D016207:Cytokines / Q000096:biosynthesis* / Q000378:metabolism; D005260:Female; D005881:Gingiva / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000150:complications / Q000276:immunology / Q000378:metabolism*; D007371:Interferon-gamma / Q000096:biosynthesis / Q000276:immunology; D007378:Interleukins / Q000096:biosynthesis; D007413:Intestinal Mucosa / Q000276:immunology / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010518:Periodontitis / Q000150:complications / Q000276:immunology / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000276:immunology
chemical_list: D016207:Cytokines; D007378:Interleukins; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma
keywords: Cytokines; Gingiva; Inflammatory bowel disease; Periodontitis