Circulating Pro-Resolving Mediators Maresin-1 and Maresin-2 and Adipolin/CTRP12 in Adults with Atopic Dermatitis: A...

Background and Objectives: Defective resolution of inflammation may contribute to chronicity in atopic dermatitis (AD). Maresin-1 (MaR1) and Maresin-2 (MaR2) are docosahexaenoic acid-derived specialised pro-resolving mediators, and adipolin/C1q/TNF-related protein 12 (CTRP12) is an adipokine with anti-inflammatory properties; to our knowledge, none has been evaluated in the circulation of patients with AD. Materials and Methods: In this single-centre case-control study, 44 adults with AD and 44 healthy controls were enrolled. Serum MaR1, MaR2, and adipolin were measured by enzyme-linked immunosorbent assay, and disease severity was graded with the Scoring Atopic Dermatitis (SCORAD) index and the Eczema Area and Severity Index (EASI). Between-group comparisons were complemented by covariate-adjusted models (age, sex, body mass index, smoking), Spearman correlation, receiver operating characteristic (ROC) analysis, and false discovery rate control. Results: Serum adipolin (3.16 vs. 3.23 ng/mL; p = 0.211), MaR1 (140.31 vs. 141.09 ng/L; p = 0.815), and MaR2 (67.56 vs. 72.29 pg/mL; p = 0.512) did not differ between patients and controls, and the null findings persisted after adjustment (all p ≥ 0.306). None of the three biomarkers correlated with SCORAD or EASI (all p ≥ 0.389) or discriminated patients from controls (area under the ROC curve 0.459-0.578). Results were unchanged when measurements outside the assay calibration ranges (adipolin, 67.0% below; MaR1, 14.8% and MaR2, 13.6% above) were censored. Serum lactate dehydrogenase was higher in patients (217.52 vs. 183.39 U/L; q = 0.004) and correlated with SCORAD (ρ = 0.404) and EASI (ρ = 0.349). Adipolin and MaR1 were strongly correlated (ρ = 0.815), including among samples with adipolin below the calibration range (ρ = 0.640). Conclusions: Circulating MaR1, MaR2, and adipolin/CTRP12 were not altered in adults with AD and do not appear useful as standalone diagnostic or severity biomarkers, although compartmentalised cutaneous activity cannot be excluded. The adipolin-MaR1 correlation showed features of an analytical artefact and should not be interpreted biologically.