Reduced Plasma Antioxidant Concentrations and Increased Oxidative DNA Damage in Inflammatory Bowel Disease

Background: Oxidative stress is believed to play a key role in the pathogenesis of inflammatory bowel disease (IBD)-related intestinal damage. Circulating antioxidants may have a role to play in preventing free radical-mediated tissue injury. Methods: Plasma vitamin A, E and carotenoid concentrations, leukocytic genomic damage and 8-hydroxy-deoxy-guanosine (8-OHdG) concentration were determined in 46 ulcerative colitis (UC) patients, 37 Crohn disease (CD) patients and 386 controls. A 20 ml blood sample was taken from each subject for antioxidant and 8-OHdG measurements. A food frequency questionnaire was administered to a sample of subjects from each group to evaluate daily intake of dietary compounds. Results: Antioxidant concentration was significantly reduced in IBD patients, particularly in those with active disease, with respect to controls ( P < 0.0001). 8-OHdG concentrations were significantly increased in IBD patients compared to controls, independent of disease activity ( P < 0.05). No correlatio...