Evaluation of saliva and serum levels of 8-hydroxideoxyguanosine (8-OHDG) and forkhead BOX-O1 (FOXO1) i̇n periodontitis patients

Evaluation Of Saliva And Serum Levels Of 8-Hydroxideoxyguanosine (8-Ohdg) And Forkhead Box-O1 (Foxo1) İn Periodontitis Patients Periodontitis; It is a chronic disease characterized by destruction of tooth support tissues and disruption of host inflammatory immune response. The mechanism of periodontal tissue destruction mainly involves disruption of the homeostatic balance between proteolytic enzymes and inhibitors, reactive oxygen species (ROS) and antioxidant (AO) system. It is active in depolymerization, lipid peroxidation, oxidation of enzymes such as antiproteases, induction of proinflammatory cytokines and DNA damage. As a direct or indirect result of antioxidant deficiency with excessive ROS activity, activation of redox sensitive transcription factors occurs and the inflammatory process begins. Periodontal tissue damage occurs. 8-hydroxydeoxyguanosine (8-OHdG) is an oxidized nucleoside released into body fluids by DNA repair. Studies have shown that 8-OHdG in body fluids acts as a marker of oxidative stress and is used to assess oxidative damage in disorders including chronic inflammatory diseases. FoxOs are members of the O (other) class of the Forkhead superfamily. Four members of this class are currently known, FoxO1, FoxO3, FoxO4 and FoxO6. Active FOX-O plays a role in protection from oxidative stress through the induction of enzymes that degrade ROS. FoxO also antagonizes oxidative stress through the transcription of manganese superoxide dismutase (MnSOD), which catalyzes the conversion of O2 to H2O2. In addition, FoxO1 resists oxidative stress by raising antioxidant enzymes. FOX-O1 protein, a transcription factor; It acts as a key regulator in a number of cellular processes, including cell survival and differentiation, reduction of reactive oxygen species (ROS), and apoptosis. The role of FoxO1 in improving antioxidant defense shows FoxO1 as a candidate target of periodontitis treatment. On the other hand, its relationship with some systemic diseases such as cardiovascular disease, brain and skeletal muscle diseases has been revealed. However, there is not enough data on its relationship with periodontitis, which is also an inflammatory disease. .The purpose of our work; The aim of this study is to determine FOX-O1 and 8-OHdG levels in serum and saliva samples of individuals with periodontitis and periodontally healthy individuals, and to evaluate the relationship of these markers with each other and with periodontal clinical parameters. For this purpose, 19 patients diagnosed with generalized stage III grade C periodontitis, 20 patients diagnosed with generalized stage III grade B periodontitis and 20 patients who were periodontal and systemically healthy were included in the study. FoxO-1 and 8-OHdG levels in serum and saliva samples obtained from 59 individuals. It was evaluated using the ELISA method. All clinical periodontal parameters (PI, CD, SKI, CAC) were found to be statistically significantly higher in both periodontitis groups compared to the K group (p<0.05). 8-OHdG salivary levels were significantly higher in both periodontitis groups compared to the control group. The salivary levels of FOXO1 were found to be significantly lower in both periodontitis groups compared to the control group. All clinical periodontal parameters show moderate positive correlation with salivary 8-OHdG level (r= 0.570 for CD, r= 0.573 for SKI, respectively). r= 0.470, r= 0.600 for BAC). While the salivary FOXO1 level has only a low-grade negative correlation with SKI (r= -0.336), it does not correlate with other clinical parameters. salivary FOXO1 level; 8-OHdG has a low degree of negative correlation with salivary level. (r= -0.395) With our current literature, it is known that due to the inflammatory character of periodontal disease, increased oxidative stress and decreased antioxidant level activate various destructive mechanisms such as increased inflammation, endothelial and mitochondrial dysfunction, and apoptosis. For this reason, it is an expected result that 8-Ohdg levels, an important parameter indicating DNA damage and oxidative stress, are expected to be increased in disease groups and is consistent with literature data. The deterioration of tissue homeostasis in favor of oxidants is compatible with decreased FoxO-1 level. The role of FOX-O1 in supporting antioxidant defense may suggest that FOX-O1 is a candidate target of periodontitis treatment. Future studies should try to explain the place of FOXO1 in the treatment of periodontitis. Key words: Periodontitis, 8-Hidroksideoksiguanozin (8-Ohdg), Forkhead Box-O1 (Foxo1) Oxidative Stress