Investigating the Extent of mRNAs of the Genes Associated with Apoptosis and OGG1 in the Gingival Connective Tissue of Patients Suffering from Chronic Periodontitis and Diabetes Mellitus.

OBJECTIVES: Cellular apoptosis plays a key role in the pathogenesis of periodontal disease. Meanwhile, diabetes mellitus can also promote cellular apoptosis of connective tissues. Abnormalities in the function of 8-oxoguanine DNA glycosylase (OGG1) can promote oxidative DNA damage, especially in the mitochondria. This study was performed to investigate expression of the genes associated with apoptosis and OGG1 in the gingival connective tissue of patients suffering from chronic periodontitis and diabetes mellitus.

METHODS: Forty patients with diabetes and chronic periodontitis along with 20 nondiabetic patients with chronic periodontitis were investigated in this study. Four weeks after scaling and root planning for the treatment of periodontitis, periodontal surgery was performed. The gingival tissues obtained during the surgery were sent to the laboratory in order to investigate the expression of genes associated with apoptosis and OGG1.

RESULTS: The mRNA and protein levels of caspase 3 and 9 were higher in the patients suffering from both diabetes and periodontitis compared to the nondiabetic chronic periodontitis patients (P<0.001). Furthermore, the expression level of OGG1 gene was higher in patients with chronic periodontitis and diabetes mellitus compared to the chronic periodontitis nondiabetic patients, though this difference was not significant.

CONCLUSION: The expression levels of genes associated with apoptosis and OGG1 in the gingival connective tissue of diabetic individuals with chronic periodontitis was higher than in nondiabetics with identical periodontal conditions. Thus, the signals and function of the genes examined in this study can be important and useful factor for further investigation in the treatment of patients with both periodontitis and diabetes.