Total antioxidant status and 8-hydroxy-2′-deoxyguanosine levels in gingival and peripheral blood of periodontitis patients

Introduction: The aim of this study was to determine 8-OHdG concentration as a biomarker of oxidant-induced DNA damage and to assess total antioxidant status (TAS) in gingival and peripheral blood during periodontal lesion. Materials and Methods: The study included 56 untreated periodontitis patients (26 with aggressive periodontitis, and 30 with chronic periodontitis (CP). The control group consisted of 25 healthy volunteers without pathological changes in the periodontium. Competitive ELISA was used to measure 8-OHdG. A colorimetric method based on the reduction of ABTS(o+)radical cation generation was used to measure TAS. Results: Significantly higher 8-OHdG concentrations were detected in the gingival blood in both groups of patients with periodontitis than in the control group. Subjects with CP had significantly decreased TAS levels in the gingival blood compared with the control group. A significantly decreased TAS level in the peripheral blood in both patient groups compared with the control group was found. Significant positive correlation between TAS levels in venous and gingival blood in all the periodontitis patients and in the CP group was observed. Conclusions: The oxidative burst in periodontitis may lead to significant local damage to nucleic acids. The significantly decreased TAS level in the gingival blood of CP patients compared with the healthy subjects suggests the possibility of a significant decrease in local antioxidant system capacity during the course of periodontitis. The decreased TAS level in the peripheral blood in the group of all patients with periodontitis may be one of the pathogenic mechanisms underlying the links between periodontal disease and several systemic diseases for which periodontitis is regarded as a independent risk factor.