title: Alteration of PTGS2 promoter methylation in chronic periodontitis.
abstract: Levels of prostaglandin E(2) and the prostaglandin-endoperoxide synthase-2 (PTGS2, or COX-2) increase in actively progressing periodontal lesions, but decrease in chronic disease. We hypothesized that chronic inflammation is associated with altered DNA methylation levels within the PTGS2 promoter, with effects on COX-2 mRNA expression. PTGS2 promoter methylation levels from periodontally inflamed gingival biopsies showed a 5.06-fold increase as compared with non-inflamed samples (p = 0.03), and the odds of methylation in a CpG site in the inflamed gingival group is 4.46 times higher than in the same site in the non-inflamed group (p = 0.016). The level of methylation at -458 bp was inversely associated with transcriptional levels of PTGS2 (RT-PCR) (p = 0.01). Analysis of the data suggests that, in chronically inflamed tissues, there is a hypermethylation pattern of the PTGS2 promoter in association with a lower level of PTGS2 transcription, consistent with a dampening of COX-2 expression in chronic periodontitis. These findings suggest that the chronic persistence of the biofilm and inflammation may be associated with epigenetic changes in local tissues at the biofilm-gingival interface.
authors.affiliation: Center for Oral and Systemic Diseases, University of North Carolina at Chapel Hill, Durham, 27709, USA.
authors.forename: S
authors.initials: S
authors.lastname: Zhang
authors.forename: S P
authors.initials: SP
authors.lastname: Barros
authors.forename: M D
authors.initials: MD
authors.lastname: Niculescu
authors.forename: A J
authors.initials: AJ
authors.lastname: Moretti
authors.forename: J S
authors.initials: JS
authors.lastname: Preisser
authors.forename: S
authors.initials: S
authors.lastname: Offenbacher
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D055113:Chronic Periodontitis / Q000201:enzymology* / Q000235:genetics*; D018899:CpG Islands / Q000235:genetics; D051546:Cyclooxygenase 2 / Q000096:biosynthesis / Q000235:genetics*; D019175:DNA Methylation; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D008297:Male; D008875:Middle Aged; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000096:biosynthesis; D014158:Transcription, Genetic; D055815:Young Adult
chemical_list: D012333:RNA, Messenger; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human