title: HMGB1 localization during experimental periodontitis.
abstract: OBJECTIVE
  This study sought to investigate the in vitro expression profile of high mobility group box 1 (HMGB1) in murine periodontal ligament fibroblasts (mPDL) stimulated with LPS or IL-1β and in vivo during ligature- or LPS-induced periodontitis in rats.
  
  
  METHODS
  For the in vivo study, 36 rats were divided into experimental and control groups, and biopsies were harvested at 7-30 d following disease induction. Bone loss and inflammation were evaluated. HMGB1 expression was assessed by immunohistochemistry, qPCR, and Western blot.
  
  
  RESULTS
  Significant increases in mPDL HMGB1 mRNA occurred at 4, 8, and 12 h with protein expression elevated by 24 h. HMGB1 mRNA expression in gingival tissues was significantly increased at 15 d in the LPS-PD model and at 7 and 15 d in the ligature model. Immunohistochemical staining revealed a significant increase in the number of HMGB1-positive cells during the experimental periods.
  
  
  CONCLUSIONS
  The results show that PDL cells produce HMGB1, which is increased and secreted extracellularly after inflammatory stimuli. In conclusion, this study demonstrates that HMGB1 may be associated with the onset and progression of periodontitis, suggesting that further studies should investigate the potential role of HMGB1 on periodontal tissue destruction.
authors.affiliation: Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Universidade Estadual Paulista (UNESP), Rua Humaitá, 1680, 2° Andar, Centro, 14801-903 Araraquara, SP, Brazil.
authors.forename: Andressa Vilas Boas
authors.identifier: 0000-0002-2756-5947
authors.initials: AV
authors.lastname: Nogueira
authors.affiliation: Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Universidade Estadual Paulista (UNESP), Rua Humaitá, 1680, 2° Andar, Centro, 14801-903 Araraquara, SP, Brazil.
authors.forename: João Antonio Chaves
authors.initials: JA
authors.lastname: de Souza
authors.affiliation: Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Universidade Estadual Paulista (UNESP), Rua Humaitá, 1680, 2° Andar, Centro, 14801-903 Araraquara, SP, Brazil.
authors.forename: Rafael Scaf
authors.identifier: 0000-0003-1110-6233
authors.initials: RS
authors.lastname: de Molon
authors.affiliation: Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Universidade Estadual Paulista (UNESP), Rua Humaitá, 1680, 2° Andar, Centro, 14801-903 Araraquara, SP, Brazil.
authors.forename: Elyne da Silva Mariano
authors.initials: Eda S
authors.lastname: Pereira
authors.affiliation: Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Universidade Estadual Paulista (UNESP), Rua Humaitá, 1680, 2° Andar, Centro, 14801-903 Araraquara, SP, Brazil.
authors.forename: Sabrina Garcia
authors.initials: SG
authors.lastname: de Aquino
authors.affiliation: Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, 1011 N. University Avenue, Ann Arbor, MI 48109-1078, USA.
authors.forename: William V
authors.initials: WV
authors.lastname: Giannobile
authors.affiliation: Department of Diagnosis and Surgery, School of Dentistry at Araraquara, Universidade Estadual Paulista (UNESP), Rua Humaitá, 1680, 2° Andar, Centro, 14801-903 Araraquara, SP, Brazil.
authors.forename: Joni Augusto
authors.initials: JA
authors.lastname: Cirelli
mesh_terms: D000818:Animals; D018450:Disease Progression; D005347:Fibroblasts / Q000378:metabolism*; D005786:Gene Expression Regulation; D024243:HMGB1 Protein / Q000378:metabolism*; D007150:Immunohistochemistry; D053583:Interleukin-1beta / Q000378:metabolism; D008070:Lipopolysaccharides / Q000737:chemistry; D008297:Male; D010513:Periodontal Ligament / Q000378:metabolism*; D010518:Periodontitis / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
chemical_list: D024243:HMGB1 Protein; C104200:Hbp1 protein, rat; D053583:Interleukin-1beta; D008070:Lipopolysaccharides; D012333:RNA, Messenger