title: Diabetes modulates gene expression in the gingival tissues of patients with chronic periodontitis.
abstract: OBJECTIVE
  This study evaluated whether diabetes modulates gene expression [interleukin (IL)-1beta, IL-1ra, IL-6, IL-8, IL-10; tumor necrosis factor (TNF)-alpha; interferon (IFN)-gamma, receptor activator of NF-kappaB ligand (RANKL) and osteoprotegerin (OPG)] in sites with periodontitis.
  
  
  METHODS
  Gingival biopsies were harvested and divided into three groups--Control group: systemically and periodontally healthy subjects (n = 10); Periodontitis group: systemically healthy subjects diagnosed with chronic periodontitis (n = 20); Diabetes group: type 1 diabetic subjects, diagnosed with chronic periodontitis (n = 20). Total RNA was obtained and analyzed by quantitative polymerase chain reaction.
  
  
  RESULTS
  Data analysis demonstrated that, except for OPG, mRNA levels for all factors were increased by inflammation (P < 0.001). Interleukin-1beta, IL-1ra, IL-6, IL-8, IFN-gamma, and RANKL mRNA levels were higher in the diabetic group when compared with the control non-periodontitis group (P < 0.05), whereas IL-10 and OPG were lower (P < 0.05). No difference was observed for TNF-alpha between diabetic and control groups (P > 0.05). Diabetes lowered IL-1beta, IL-8, IL-10, TNF-alpha, RANKL, and OPG mRNA levels in sites with comparable type of periodontitis (P < 0.001). Moreover, increased RANKL:OPG and IL-6:IL-10 ratios were found.
  
  
  CONCLUSIONS
  Taken together, these data suggest that decreased levels of IL-10 and OPG may play an important role in the periodontal breakdown in diabetic patients.
authors.affiliation: Department of Periodontics, Dental Research Division, Guarulhos University, Guarulhos, SP, Brazil.
authors.forename: P M
authors.initials: PM
authors.lastname: Duarte
authors.forename: J B C
authors.initials: JB
authors.lastname: Neto
authors.forename: M Z
authors.initials: MZ
authors.lastname: Casati
authors.forename: E A
authors.initials: EA
authors.lastname: Sallum
authors.forename: F H
authors.initials: FH
authors.lastname: Nociti
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D016207:Cytokines / Q000032:analysis; D003922:Diabetes Mellitus, Type 1 / Q000150:complications*; D005260:Female; D015870:Gene Expression / Q000502:physiology*; D005881:Gingiva / Q000737:chemistry*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010518:Periodontitis / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis*
chemical_list: D016207:Cytokines; D012333:RNA, Messenger