Biochemical evaluation of Sestrin2 and Nrf2/Keap1 levels in periodontal diseases

Periodontal diseases are chronic conditions primarily caused by microbial dental plaque. They develop under the influence of multiple factors and are characterised by inflammatory processes. During this process, an increase in reactive oxygen species (ROS), which are produced by polymorphonuclear leukocytes (PMNL), leads to a disruption in the balance between oxidant and antioxidant systems, resulting in oxidative stress (OS). This is considered one of the main mechanisms triggering destruction of periodontal tissue. This study evaluated the serum levels of the antioxidant defence components Sestrin-2 and Nrf-2/Keap-1, the relationship of which with periodontal diseases has not been sufficiently elucidated in the literature. The study aimed to compare the levels of these molecules in individuals with different periodontal conditions. This cross-sectional study included 80 individuals who visited the Department of Periodontology at the Faculty of Dentistry at Gaziantep University and who had no systemic diseases or smoking habits. Participants were divided into four groups according to their periodontal status: individuals with healthy periodontal tissue (n = 20); individuals with plaque-related gingivitis (n = 20); individuals with stage I–II periodontitis (n = 20); and individuals with stage III–IV periodontitis (n = 20). Informed consent was obtained from all participants, after which clinical and radiographic evaluations were performed. The following clinical parameters were measured: probing pocket depth (PPD), clinical attachment level (CAL), plaque index (PI) and gingival index (GI). Serum samples were then collected and analysed for Sestrin-2, Nrf-2 and Keap-1 levels using the ELISA method. The analysis results showed that Sestrin-2, Nrf-2 and Keap-1 levels were lower, particularly in the Stage III-IV periodontitis group. However, these differences were not found to be statistically significant (p>0.05). It is noteworthy that these biomarkers associated with oxidative stress tend to decrease in advanced stages of periodontal disease. Further advanced, prospective studies are required to better understand the role of these molecules in the pathogenesis of periodontal disease.