8-Epi-Prostaglandin F2α as a Redox Biomarker in Inflammatory Bowel Disease

Background: Oxidative stress plays a significant role in inflammatory bowel disease (IBD), yet the clinical relevance of specific lipid peroxidation markers remains insufficiently defined. This study evaluated serum levels of 8-epi-prostaglandin F2α (8-epi-PGF2α), an isoprostane generated through non-enzymatic lipid oxidation, and examined its relationship with antioxidant enzymes and clinical disease activity in ulcerative colitis (UC) and Crohn's disease (CD). Methods: Eighty-seven patients (55 UC and 32 CD) were assessed for serum 8-epi-PGF2α, superoxide dismutase 1 (SOD1), and glutathione peroxidase 1 (GPX1), and classified as having mild, moderate, or severe disease. Statistical analyses included comparative analysis, two-way ANOVA, multiple linear regression, and Ridge logistic regression. To address potential dietary confounding, total energy intake, Mediterranean Diet Score (MDS), and antioxidant supplement use were incorporated into the regression models. Results: Serum levels of 8-epi-PGF2α and GPX1 were significantly higher in UC than in CD (ρ = 0.001 and p = 0.042), and both increased with greater disease severity (p < 0.001 and p = 0.001). In UC, 8-epi-PGF2α positively correlated with high-sensitivity C-reactive protein (hs-CRP), white blood cells (WBC), and Truelove-Witts Index (TWI), and negatively with hemoglobin (False Discovery Rate (FDR)-adjusted q < 0.100). In CD, it correlated with the Harvey-Bradshaw Index (HBI) and disease duration (FDR-adjusted q < 0.050). Inter-biomarker analyses showed a strong association between 8-epi-PGF2α and GPX1 in UC (ρ = 0.677, p < 0.0001, FDR < 0.0001), suggesting coordinated activation of oxidative and antioxidant pathways. The observed associations remained consistent after adjustment for dietary factors, supporting the robustness of the findings. Because these results are cross-sectional, they cannot establish causality and should be interpreted with caution. Conclusions: Nevertheless, 8-epi-PGF2α emerges as a promising non-invasive biomarker for assessing oxidative stress and disease activity in IBD, with potential clinical applicability for patient monitoring and therapeutic evaluation.