title: Effects of probiotic therapy on metabolic and inflammatory parameters of rats with ligature-induced periodontitis associated with restraint stress.
abstract: BACKGROUND
  This study evaluates the effects of probiotic therapy (PT) in rats with ligature-induced periodontitis associated with restraint stress.
  
  
  METHODS
  Sixty-four rats were divided into control, stress (STR), probiotic (PROB), periodontal disease (PD), STR-PROB, STR-PD, STR-PROB-PD, and PROB-PD groups. The probiotic was added to the drinking water for 44 days. PD was induced by a ligature. In STR groups, the animals were subjected to restraint stress for 2.5 hours per day for 30 days.
  
  
  RESULTS
  Rats with PD exhibited increased alveolar bone loss (P <0.05), as well as increased levels of cyclooxygenase-2, serum C-terminal telopeptide (CTX), p38 mitogen-activated protein kinase (p38), and receptor activator of nuclear factor-κB ligand and decreased levels of osteoprotegerin (OPG). Stressed rats presented high levels of C-peptide, corticosterone, and glucose (P <0.05). In general, the presence of stress reduced the expression of CTX and p38 (P <0.05). PT reduced alveolar bone loss in unstressed animals. It also decreased expression of CTX and induced increased expression of OPG in unstressed animals with PD. However, PT was not effective in preventing bone loss or altering the expression of inflammatory markers in stressed animals. PT decreased the number of inflammatory cells in the periodontal tissue (P <0.05). Groups with stress and PD showed decreased villous height and crypt depth. Stress seemed to prevent part of the probiotic beneficial effects on the small intestine.
  
  
  CONCLUSIONS
  Based on the methodology used, PT may reduce tissue breakdown resulting from PD in unstressed rats. The protocol used for restraint stress influenced the immunomodulatory effects of PT in intestinal and periodontal tissues.
authors.affiliation: Department of Physiology and Pharmacology, Federal University of Lavras (UFLA), Lavras, MG, Brazil.
authors.forename: Renata de C
authors.initials: Rde C
authors.lastname: Foureaux
authors.forename: Michel R
authors.initials: MR
authors.lastname: Messora
authors.forename: Luiz Fernando F
authors.initials: LF
authors.lastname: de Oliveira
authors.forename: Marcelo H
authors.initials: MH
authors.lastname: Napimoga
authors.forename: Andressa N J
authors.initials: AN
authors.lastname: Pereira
authors.forename: Matheus S
authors.initials: MS
authors.lastname: Ferreira
authors.forename: Luciano J
authors.initials: LJ
authors.lastname: Pereira
mesh_terms: D016301:Alveolar Bone Loss / Q000276:immunology / Q000378:metabolism; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D002096:C-Peptide / Q000032:analysis; D024042:Collagen Type I / Q000097:blood; D003345:Corticosterone / Q000032:analysis; D051546:Cyclooxygenase 2 / Q000032:analysis; D005891:Gingivitis / Q000276:immunology / Q000378:metabolism / Q000628:therapy; D007413:Intestinal Mucosa / Q000473:pathology; D007421:Intestine, Small / Q000473:pathology; D008297:Male; D053244:Osteoprotegerin / Q000032:analysis; D010455:Peptides / Q000097:blood; D010518:Periodontitis / Q000276:immunology / Q000378:metabolism / Q000628:therapy*; D019936:Probiotics / Q000627:therapeutic use*; D053245:RANK Ligand / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D013312:Stress, Physiological / Q000276:immunology*; D013315:Stress, Psychological / Q000150:complications* / Q000276:immunology / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000032:analysis
chemical_list: D001786:Blood Glucose; D002096:C-Peptide; D024042:Collagen Type I; D053244:Osteoprotegerin; D010455:Peptides; D053245:RANK Ligand; C506032:Tnfrsf11b protein, rat; C052929:collagen type I trimeric cross-linked peptide; D051546:Cyclooxygenase 2; C489691:Ptgs2 protein, rat; D048051:p38 Mitogen-Activated Protein Kinases; D003345:Corticosterone
keywords: Alveolar bone loss; inflammation; models, animal; periodontal diseases; probiotics; restraint, physical