Adiponectin is associated with the periodontal inflamed surface area (PISA)

Objectives:  Adiponectin is elevated in saliva and gingival crevicular fluid from patients with periodontal disease and decreases after treatment.  However, our knowledge of the role of adiponectin remains limited. We evaluated the relationship of adiponectin to salivary cytokines and to PISA as measures of inflammation in periodontal disease. 

Methods:  Saliva samples were collected from 94 patients with T2DM (44 chronic periodontitis, 37 gingivitis, 13 periodontally healthy) and 83 matched non-diabetics (48 chronic periodontitis, 19 gingivitis, 16 periodontally healthy) using a 30s 10 ml 0.9% saline rinse technique. Adiponectin was measured using ELISA and cytokines using an multiplex-array. PISA values were obtained according to Nesse et al. (2011). Correlations between adiponectin and cytokines/PISA were analysed with Spearman; Kruskal-Wallis and Mann-Whitney U were used for analysis of group differences for PISA data.

Results: PISA values ranged from 32±54 mm² in periodontally healthy subjects (p<0.001) to 340±179 mm² in gingivitis (p<0.001) and to 915±532 mm² (p<0.001) in periodontal disease. Adiponectin levels correlated with IL-6 (p<0.01), IL-1β (p<0.01) and IFN-γ (p<0.05) in T2DM patients and with IL-6 (p<0.01), IL-1β (p<0.05) and TNF-α (p<0.01) in non-diabetics. Adiponectin correlated with PISA in both T2DM (p<0.01) and non-diabetics (p<0.05). Adiponectin correlated with IL-6 (p<0.01) and TNF-α (p<0.01) in periodontally healthly subjects, with IL-6 (p<0.01), IL-1β (p<0.05), TNF-α (p<0.01) and IFN-γ (p<0.01) in gingivitis and with IL-6 (p<0.05) in periodontal disease, irrespective of diabetic status. Adiponectin correlated with PISA in the periodontal disease group only (p<0.01). 

Conclusion: Salivary adiponectin potentially plays a pro-inflammatory role in the mouth, as it significantly correlates with pro-inflammatory cytokines. In addition, adiponectin levels are positively associated with PISA in periodontal disease. Altered adiponectin concentrations in T2DM potentially impact on immune responses but the precise role of adiponectin in periodontal disease remains to be determined. The work was supported with an ODRT grant (BH102070).