Effects of TNF-alpha blocking on experimental periodontitis and type 2 diabetes in obese diabetic Zucker rats.

OBJECTIVE: Tumour necrosis factor alpha (TNF-alpha) is considered a key signalling modulator in the pathogenesis of both periodontitis (PD) and type 2 diabetes mellitus (DM2). This study aims at elucidating the effect of TNF-alpha blocking on the interplay between PD and DM2. METHODS: Obese diabetic Zucker rats and their lean littermates were divided into five treatment groups with or without periodontitis. Anti-TNF-alpha treatment was provided with Etanercept injections. Diabetic state was evaluated by oral glucose tolerance test, the homeostatic model assessment, free fatty acids and blood glucose. Systemic inflammation was assessed by measurement of interleukin (IL)-1beta, IL-6 and TNF-alpha in plasma. Kidney complications were evaluated by real-time rtPCR, creatinine clearance rate, urinary albumin excretion and increase in weight. PD was evaluated by registration of alveolar bone level. RESULTS: After 4 weeks the diabetic state was modified by Etanercept treatment with lower insulin levels and lower homeostatic model assessment. Furthermore, while kidney complications were reduced by Etanercept treatment, PD had no effect. PD was influenced by diabetic state, but the impact was attenuated by Etanercept treatment. CONCLUSION: In this study anti-TNF-alpha treatment improved glucose tolerance and compensated for the increased periodontal disease in obese diabetic Zucker. PD did not influence diabetic parameters assessed including complications of the rats kidneys.