Serum and gingival crevicular fluid asprosin levels in obese and normal-weight individuals with and without periodontitis: a cross-sectional study

Obesity and periodontitis are chronic inflammatory conditions linked by shared immunometabolic pathways. Although asprosin has been implicated in metabolic regulation and systemic inflammation, its role in the immunometabolic interaction between obesity and periodontal inflammation remains unclear. This study evaluated local and systemic levels of asprosin, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) in obese and normal-weight individuals with and without periodontitis. This cross-sectional study included 60 individuals aged 18–65 years, categorized by body mass index (BMI) as normal weight (18.5–24.9 kg/m²) or obese (≥ 30 kg/m²). Participants were further classified as periodontally healthy or with periodontitis, forming four groups: normal-weight periodontally healthy (NH), obese periodontally healthy (OH), normal-weight periodontitis (NP), and obese periodontitis (OP) (n = 15 each). Plaque index, gingival index, probing pocket depth, clinical attachment level, and bleeding on probing were recorded. Gingival crevicular fluid (GCF) and serum samples were analyzed for asprosin, TNF-α, and IL-6 using an enzyme-linked immunosorbent assay. Intergroup comparisons were performed using a rank-based general linear model adjusted for age and sex. Serum asprosin levels were lower in the NH group than in the NP (p = 0.025), OH (p < 0.001), and OP (p < 0.001) groups and were also lower in the NP group than in the OH (p = 0.006) and OP (p = 0.021) groups. GCF asprosin levels were lower in the NH group compared with the OH (p < 0.001) and OP (p = 0.017) groups, and were also lower in the NP group than in the OH (p = 0.042) and OP (p = 0.022) groups. IL-6 levels were higher in the OH group than in the NH group (p = 0.050), whereas serum TNF-α did not differ significantly among groups (p = 0.078). Although overall group differences were observed for GCF IL-6 (p = 0.014) and TNF-α (p = 0.008), overlap in interquartile ranges limited consistent pairwise comparisons. GCF and serum asprosin levels were higher in obese individuals than in normal-weight participants, while serum asprosin levels were higher in normal-weight individuals with periodontitis than in normal-weight periodontally healthy individuals. These findings are consistent with an association between asprosin levels, obesity, and periodontal status, indicating that obesity status should be considered when interpreting asprosin levels in periodontal conditions. The study was retrospectively registered on ClinicalTrials.gov on March 17, 2025 (Identifier: NCT06879951).