Gastrointestinal and liver diseases The role of oxidative stress in the etiopathogenesis of celiac disease Mustafa Kaplan1, Ihsan Ates2, Mahmut Yüksel1, Yasemin Ozderin Ozin1, Muhammed Yener Akpinar1, Canan Topcuoglu3, Ertuğrul Kayaçetin1 1Department of Gastroenterology,Turkey Yuksek Ihtisas Training and Research Hospital, Ankara, Turkey 2Department of Internal Medicine, 3Department of Biochemistry, Ankara Numune Training and Research Hospital, Ankara, Turkey Gastrointestinal and liver diseases P.0396 Introduction Results In comparison to the control group; celiac patients had lower TAS (1.3 ± 0.2 mmol Trolox equivalent / L vs 1.8 ± 0.2 mmol Trolox equivalent / L; p < 0.001), PON1 (122.5 ± 36.4 U / L vs 155.8 ± 47.6 U / L; p < 0.001) and arylesterase (971.06 ± 235.1 U / L vs 1249.2 ± 279.2 U / L; p < 0.001) levels and celiac patients had significantly higher TOS (6.9 ± 2.0 micromolar H2O2 Eq / L vs 4.3 ± 1.9 micromolar H2O2 Eq / L; p < 0.001) and OSI (5.3 ± 1.5 vs 2.4 ± 1.1; p < 0.001) levels. In comparison to patients who complied with the gluten diet, had a higher OSI ratio and patients who did not comply with the diet had a lower PON1 level. A positive correlation was found between TOS and OSI rates and celiac autoantibodies and c-reactive protein levels and a negative correlation was found between arylesterase level and celiac autoantibodies. Celiac disease is a chronic inflammatory disease associated with hypersensitivity against gluten and characterized by lymphocyte infiltration in proximal part of small intestine, villous atrophy, crypt hyperplasia and mucosal damage. Although environmental, genetic, immunological and microbial factors are blamed in its etiopathogenesis, there have been studies suggesting that oxidative stress may have a role as well. Oxidative stress, mainly characterized by the increase in free radicals depending on environmental factors and the consequent cellular damage, is though have an important place in the etiology of celiac disease. Objectives Conclusions We found oxidative stress level to be higher in celiac patients compared to the control group. Oxidative stress level showed differences in celiac patients depending on gluten diet content and autoantibody positivity. The fact that c-reactive protein and celiac autoantibodies are related to oxidative stress parameters leads to the idea that oxidative stress may be effective in celiac pathogenesis. We aimed to investigate the role of overall oxidative stress in etiopathogenesis of celiac disease and its relationship with gluten diet and autoantibodies. References Methods Eighty celiac patients and 80 control group participants were included in the study. As oxidative stress parameters, we studied total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), paraoxonase 1 (PON1) and arylesterase parameters. 1. Ludvigsson JF, Leffler DA, Bai JC, Biagi F, Fasano A, Green PH, et al. The Oslo definitions for coeliac disease and related terms. Gut. 2013 Jan;62(1):43-52. PubMed PMID: 22345659. Pubmed Central PMCID: 3440559. 2. Abadie V, Sollid LM, Barreiro LB, Jabri B. Integration of genetic and immunological insights into a model of celiac disease pathogenesis. Annual review of immunology. 2011;29:493-525. PubMed PMID: 21219178. 3. Ferretti G, Bacchetti T, Masciangelo S, Saturni L. Celiac disease, inflammation and oxidative damage: a nutrigenetic approach. Nutrients. 2012 Apr;4(4):243-57. PubMed PMID: 22606367. Pubmed Central PMCID: 3347005.