title: Porphyromonas gingivalis LPS stimulation downregulates DNMT1, DNMT3a, and JMJD3 gene expression levels in human HaCaT keratinocytes.
abstract: OBJECTIVE
  The role of epigenetic regulation in inflammatory diseases such as periodontitis is poorly known. The aim of this study was to assess whether Porphyromonas gingivalis lipopolysaccharide (LPS) can modulate gene expression levels of the some enzymes that promote epigenetic events in cultures of the human keratinocytes and gingival fibroblasts. In addition, the same enzymes were evaluated in gingival samples from healthy and periodontitis-affected individuals.
  
  
  METHODS
  Primary gingival fibroblast and keratinocyte (HaCaT) cultures were treated with medium containing P. gingivalis LPS or P. gingivalis LPS vehicle for 24 h. After this period, cell viability was assessed by MTT test and total RNA extracted to evaluate gene expression levels of the following enzymes by qRT-PCR: DNA methyltransferase 1 (DNMT1), DNA methyltransferase 3a (DNMT3a), histone demethylases Jumonji domain containing 3 (JMJD3) and ubiquitously transcribed tetratricopeptide repeat, X chromosome (UTX). To evaluate gene expression in healthy and periodontitis-affected individuals, total RNA was extracted from biopsies of gingival tissue from healthy and periodontitis sites, and gene expression of DNMT1, DNAMT3a, JMJD3, and UTX was evaluated by qRT-PCR.
  
  
  RESULTS
  No significant differences were found in the gene expression analysis between healthy and periodontitis-affected gingival samples. The results showed that LPS downregulated DNMT1 (p < 0.05), DNMT3a (p < 0.05), and JMJD3 (p < 0.01) gene expression in HaCaT cells, but no modulation was observed in gingival fibroblasts.
  
  
  CONCLUSIONS
  P. gingivalis LPS exposure to human HaCaT keratinocytes downregulates gene expression of the enzymes that promote epigenetic events.
  
  
  CONCLUSIONS
  The advance knowledge about epigenetic modifications caused by periodontopathogens may to possibly led to the development of new periodontal therapies.
authors.affiliation: Department of Morphology Division of Histology, Piracicaba Dental School, State University of Campinas, Av. Limeira 901, Caixa Postal 052, CEP 13414-903, Piracicaba, São Paulo, Brazil.
authors.forename: Gláucia
authors.initials: G
authors.lastname: de Camargo Pereira
authors.forename: Gustavo Narvaes
authors.initials: GN
authors.lastname: Guimarães
authors.forename: Aline Cristiane
authors.initials: AC
authors.lastname: Planello
authors.forename: Mauro Pedrine
authors.initials: MP
authors.lastname: Santamaria
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: de Souza
authors.forename: Sergio Roberto
authors.initials: SR
authors.lastname: Line
authors.forename: Marcelo Rocha
authors.initials: MR
authors.lastname: Marques
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D055113:Chronic Periodontitis / Q000201:enzymology / Q000235:genetics* / Q000382:microbiology; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics; D019175:DNA Methylation / Q000235:genetics; D000090205:DNA Methyltransferase 3A; D015536:Down-Regulation; D044127:Epigenesis, Genetic / Q000187:drug effects*; D005260:Female; D005347:Fibroblasts; D005786:Gene Expression Regulation / Q000187:drug effects*; D005881:Gingiva / Q000166:cytology*; D006801:Humans; D056484:Jumonji Domain-Containing Histone Demethylases / Q000235:genetics; D015603:Keratinocytes; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D016966:Porphyromonas gingivalis / Q000472:pathogenicity*; D055815:Young Adult
chemical_list: C000717967:DNMT3A protein, human; D008070:Lipopolysaccharides; D056484:Jumonji Domain-Containing Histone Demethylases; C524220:KDM6B protein, human; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases; D000090205:DNA Methyltransferase 3A; C000619380:DNMT1 protein, human