Investigation of IL-37–Caspase-1 pathway protein levels in the gingival crevicular fluid of healthy and periodontitis patients

Periodontitis is a destructive and chronic inflammatory disease that results from a dysregulated host immune response to microbial dental biofilm. The aim of this study was to evaluate the relationship between IL-37–Caspase-1 pathway proteins and periodontal inflammation and to compare the levels of these proteins in gingival crevicular fluid (GCF) among healthy individuals and patients with varying degrees of periodontitis. The study included systemically healthy individuals aged between 35 and 50 who applied to the Periodontology Department of Tokat Gaziosmanpaşa University Faculty of Dentistry. Participants were divided into three groups based on clinical measurements: a healthy group (Group S), Grade B periodontitis group (Group B), and Grade C periodontitis group (Group C). Protein levels of IL-37, Caspase-1, Smad3, PTPN1, and NF-κB were analyzed using the ELISA method in GCF samples collected from all individuals. Clinical periodontal parameters (PI, GI, PD, CAL) were also recorded and statistically analyzed. The results showed that IL-37 levels were significantly lower in individuals with periodontitis compared to healthy individuals, and this decrease was inversely proportional to disease severity. Caspase-1 levels did not differ significantly between groups (p>0.05). While Smad3 levels showed a significant difference only between the Grade B and Grade C groups(p<0.05), a positive correlation was found between PTPN1 levels and clinical attachment level (p=0.037). NF-κB levels showed no statistically significant difference among the groups (p>0.05). Keywords: Periodontitis, IL-37, Caspase-1, Smad3, PTPN1, NF-κB, GCF, ELISA