Relationship between selenium status and biomarkers of oxidative stress in Crohn's disease

Crohn disease (CD) is characterized by chronic intestinal inflammation and various factors involved in its pathogenesis including oxidative stress. The oxidative stress in CD may compromise antioxidant nutrients, such as selenium. The aim of this study was to assess the status of selenium and its relationship with markers of oxidative stress in patients with CD in comparison to controls. The study included 47 patients with CD (20 with active disease and 27 in remission) and 25 healthy individuals. Blood samples were collected for the analysis of plasma and erythrocyte selenium concentrations using inductively coupled plasma optical emission spectrometry (ICP-OES). Selenoprotein P (SepP) was evaluated by sandwich enzyme-linked immunosorbent assay, erythrocyte glutathione peroxidase (GPx1) activity was assessed by using an automatic biochemistry analyzer, and the concentration of thiobarbituric acid reactive substances (TBARS) was measured. Comparative analyses were performed using one-way analysis of variance and Tukey's post hoc test. For correlations, Pearson's coefficient test was used. The determinants for CD and lipid peroxidation were indicated by odds ratio. Plasma and erythrocyte selenium levels and SepP concentrations were lower in the CD patient groups than in the healthy group. GPx1 activity and the concentration of TBARS were significantly higher in the CD groups. In the univariate analysis, plasma and erythrocyte selenium and TBARS were associated with CD. Patients with CD have impaired selenium status, which is related to the increased oxidative stress observed in these patients.