Cytokine levels in sites of chronic periodontitis of poorly controlled and well-controlled type 2 diabetic subjects

P>Aim This study compared the levels of tumour necrosis factor (TNF)-alpha, interferon (IFN)-gamma, interleukin (IL)-4, IL-17 and IL-23 in the gingival crevicular fluid (GCF) from well-controlled and poorly controlled type 2 diabetic subjects with chronic periodontitis, before and after periodontal therapy. Material and Methods Eighteen well-controlled (glycated haemoglobin levels <= 8%) and 20 poorly controlled (glycated haemoglobin levels > 8%) diabetic subjects were enrolled in this study. All subjects were submitted to non-surgical periodontal therapy. GCF sampling and clinical periodontal parameters were assessed before, 3 and 6 months post-therapy. Total amounts and concentrations of TNF-alpha, IFN-gamma, IL-4, IL-17 and IL-23 in the GCF were analysed by enzyme-linked immunosorbent assay (ELISA). Results The levels of IL-17 were higher in poorly than in well-controlled subjects (p < 0.05), whereas the levels of IFN-gamma were increased in well- compared with poorly controlled subjects at all experimental groups (p < 0.05). In addition, IL-4 levels were lower in well- than poorly controlled diabetic subjects at baseline (p < 0.05). There were no differences between groups for TNF-alpha and IL-23 at any time points (p > 0.05). Conclusion These results indicate a predominance of pro-inflammatory T-helper type 1 (Th1)- or Th17-cytokines in sites of chronic periodontitis from type 2 diabetic subjects, according to their glycaemic control. (AU)