Expression of Cytokines in Type 2 Diabetic Patients with Periodontitis

Objectives: This study aimed to evaluate the expression of pro and anti-inflammatory cytokines (IL-17, IL-10, IL-6, IL-4, IL-2, IFNγ, TNF-α) present in plasma and saliva in individuals with Periodontitis and Type 2 Diabetes Mellitus.
Methods: After approval by the Ethics Committee, 54 patients (≧ 30 years old ) were clinically evaluated in Brasília University Hospital and subdivided into 04 groups according to periodontal and systemic status: Group I (control): 14 patients; Group II (periodontitis): 12 patients; Group III (diabetes without periodontitis): 11 patients; Group IV (diabetes with periodontitis): 17 patients. The clinical exams were performed by a calibrated examiner. The data were analyzed by descriptive statistics, the normality of the samples was tested by the Shapiro-Wilk test and the comparison between the samples was given by the Kruskal-Wallis test and Wilcoxon-Mann-Whitney test. The p-value < 0.05 was considered statistically significant assessed by R software. The levels of cytokines were determined by CBA (cytometric beads array) kit according to the manufacturer’s instructions.
Results: No statistical difference was found between IL-17, IFN-γ, TNF-α and IL-10 markers in both saliva and plasma. Plasma IL-4 levels were different when compared to groups II and III, and groups III and IV, whereas in saliva there was no difference in either group. Saliva IL-2 level was not significantly different, whereas there was a difference in groups II and III, and groups III and IV in plasma. Saliva IL-6 levels were similar in the groups, whereas IL-6 plasma levels were different when compared to groups I and III, groups II and III, and groups III and IV.
Conclusions: IL-2 induces the production of other mediators which results in monocyte induction, while IL-4 reduces the effects of other markers. IL-6 is an important mediator of protein induction and synthesis and release during painful stimuli. These study results suggested that interleukins 2, 4 and 6 are associated with diabetic patients with periodontitis. Further studies are needed to continue to evaluate these biomarkers in this population and clarify the immunological mechanisms of periodontal disease associated with diabetes.