Crohn's disease and ulcerative colitis, known together as inflammatory bowel diseases (IBDs), and celiac disease are the most common disorders affecting not only adults but also children. Both IBDs and celiac disease are associated with oxidative stress, which may play a significant role in their etiologies. Reactive oxygen species (ROS) such as superoxide radicals (O2•-), hydroxyl radicals (•OH), hydrogen peroxide (H2O2), and singlet oxygen (1O2) are responsible for cell death via oxidation of DNA, proteins, lipids, and almost any other cellular constituent. To protect biological systems from free radical toxicity, several cellular antioxidant defense mechanisms exist to regulate the production of ROS, including enzymatic and nonenzymatic pathways. Superoxide dismutase catalyzes the dismutation of O2•- to H2O2 and oxygen. The glutathione redox cycle involves two enzymes: glutathione peroxidase, which uses glutathione to reduce organic peroxides and H2O2; and glutathione reductase, which reduces the oxidized form of glutathione with concomitant oxidation of nicotinamide adenine dinucleotide phosphate. In addition to this cycle, GSH can react directly with free radicals. Studies into the effects of free radicals and antioxidant status in patients with IBDs and celiac disease are scarce, especially in pediatric patients. It is therefore very necessary to conduct additional research studies to confirm previous data about ROS status and antioxidant activities in patients with IBDs and celiac disease, especially in children.

Department of Ecology Faculty of Humanities and Natural Sciences Prešov University in Prešov Prešov Slovak Republic

Department of Medical and Clinical Biochemistry Faculty of Medicine Pavol Jozef Šafárik University in Košice Košice Slovak Republic

Department of Medical Physiology Faculty of Medicine Pavol Jozef Šafárik University in Košice Košice Slovak Republic

Department of Physiology and Pathophysiology Faculty of Medicine University of Ostrava Ostrava Zábřeh Czech Republic

Zobrazit více v PubMed

Sato H., Shibata H., Shimizu T., Shibata S., Toriumi H., Ebine T. Differential cellular localization of antioxidant enzymes in the trigeminal ganglion. Neuroscience. 2013;248:345–358. PubMed

Navarro-Yepes J., Zavala-Flores L., Anandhan A., Wang F., Skotak M., Chandra N. Antioxidant gene therapy against neuronal cell death. Pharmacol Ther. 2014;142:206–230. PubMed PMC

Rajendran P., Nandakumar N., Rengarajan T., Palaniswami R., Gnanadhas E.N., Lakshminarasaiah U. Antioxidants and human diseases. Clin Chim Acta. 2014;436:332–347. PubMed

Wu J.Q., Kosten T.R., Zhang X.Y. Free radicals, antioxidant defense system, and schizophrenia. Prog Neuropsychopharmacol Biol Psychiatry. 2013;46:200–206. PubMed

Taniyama Y., Griendling K.K. Reactive oxygen species in the vasculature. Hypertension. 2003;42:1075–1081. PubMed

Fink M.P. Reactive oxygen species as mediators of organ dysfunction caused by sepsis, acute respiratory distress syndrome, or hemorrhagic shock: potential benefits of resuscitation with Ringer's ethyl pyruvate solution. Curr Clin Opin Nutr Metab Care. 2002;5:167–174. PubMed

Hansen J.M., Go Y.M., Jones D.P. Nuclear and mitochondrial compartmentation of oxidative stress and redox signalling. Annu Rev Pharmacol Toxicol. 2006:215–234. PubMed

Glasauer A., Chandel N.S. Targeting antioxidants for cancer therapy. Biochem Pharmacol. 2014;92:90–101. PubMed

Al-Gubory K.H., Garrel C., Faure P., Sugino N. Roles of antioxidant enzymes in corpus luteum rescue from reactive oxygen species-induced oxidative stress. Reprod Biomed Online. 2012;25:551–560. PubMed

Halliwell B. Antioxidant defence system mechanisms: from the beginning to the end (of beginning) Free Radic Res. 1999;31:261–272. PubMed

Gill S.S., Tuteja N. Reactive oxygen species and antioxidant machinery in abiotic stress tolerance in crop plants. Plant Physiol Biochem. 2010;48:909–930. PubMed

Ushio-Fukai M., Nakamura Y. Reactive oxygen species and angiogenesis: NADPH oxidase as target for cancer therapy. Cancer Lett. 2008;266:37–52. PubMed PMC

Griendling K.K., Minieri C.A., Ollerenshaw J.D., Alexander R.W. Angiotensin I stimulates NADH and NADPH oxidasae activity in cultured vascular smooth muscle cells. Circ Res. 1994;74:1141–1148. PubMed

George J., Struthers A.D. Role of urate, xanthine oxidase and the effects of allopurinol in vascular oxidative stress. Vasc Health Risk Manag. 2009;5:265–272. PubMed PMC

Pacher P., Nivorozhkin A., Szabo C. Therapeutic effects of xanthine oxidase inhibitors: renaissance half a century after the discovery of allopurinol. Pharmacol Rev. 2006;58:87–114. PubMed PMC

Stuehr D., Pou S., Rosen G.M. Oxygen reduction by nitric-oxide synthases. J Biol Chem. 2001;276:14533–14536. PubMed

Landmesser U., Dikalov S., Price S.R., McCann L., Fukai T., Holland S.M. Oxidation of tertrahydrobiopterin leads to uncoupling of endothelila cell nitric oxide synthase in hypertension. J Clin Invest. 2003;111:1201–1209. PubMed PMC

Winterbourn C.C., Vissers M.C., Kettle A.J. Myeloperoxidase. Curr Opin Hematol. 2000;7:53–58. PubMed

Eiserich J.P., Baldus S., Brennan M.L., Ma W., Zhang C., Tousson A. Myeloperoxidase, a leukocyte-derived vascular NO oxidase. Science. 2002;296:2391–2394. PubMed

Gersch C., Palii S.P., Imaram W., Kim K.M., Karumanchi A., Angerhofer A. Reactions of peroxynitrite with uric acid. Formation of reactive intermaditaes, alkylated products and triuret, and in vivo production of triuret under conditions of oxidative stress. Nucleoside Nucleotides Nucleic Acids. 2009;28:118–149. PubMed PMC

Pacher P., Beckman J.S., Liaudet L. Nitric oxide and peroxinitrite in health and disease. Physiol Rev. 2007;87:315–424. PubMed PMC

Deponte M. Glutathione catalysis and the reaction mechanism of glutathione-dependent enzymes. Biochim Biophys Acta. 2013;1830:3217–3266. PubMed

Sindhi V., Gupta V., Sharma K., Bhatnagar S., Kumari R., Dhaka N. Potential applications of antioxidants — a review. J Pharm Res. 2013;7:828–835.

Glasauer A., Chandel N.S. Targeting antioxidants for cancer therapy. Biochem Pharmacol. 2014;2:90–101. PubMed

Abreu I.A., Cabelli D.E. Superoxide dismutases — a review of the metal-associated mechanistic variations. Biochim Biophys Acta. 2010;1804:263–274. PubMed

Bonini M.G., Gabel S.A., Ranguelova K., Stadler K., Derose E.F., London R.E. Direct magnetic resonance evidence for peroxymonocarbonate involvement in the Cu, Zn-superoxide dismutase peroxidase catalytic cycle. J Biol Chem. 2009;284:14618–14627. PubMed PMC

Hough M.A., Hasnain S.S. Structure of fully reduced bovine copper zinc superoxide dismutase at 1.15 A. Structure. 2003;11:937–946. PubMed

Aksoy Y., Balk M., Ogus H., Ozer N. The mechanism of inhibition of human erythrocyte catalase by azide. Turk J Biol. 2004;28:65–70.

Gamain B., Arnaud J., Favier A., Camus D., Dive D., Slomianny C. Increase in glutathione peroxidase activity in malaria parasite after selenium supplementation. Free Radic Biol Med. 1996;21:559–565. PubMed

Arthur J.R. The glutathione peroxidases. Cell Mol Life Sci. 2000;57:1825–1835. PubMed PMC

Goyal M.M., Basal A. Hydroxyl radical generation theory: a possible explanation of unexplained actions of mammalian catalase. Int J Biochem Mol Biol. 2012;3:282–289. PubMed PMC

Chakravarti R., Gupta K., Majors A., Ruple L., Aronica M., Stuehr D.J. Novel insights in mammalian catalase heme maturation: effect of NO and thioredoxin-1. Free Radic Biol Med. 2015;82:105–113. PubMed PMC

Kirkman H.N., Rolfo M., Ferraris A.M., Ferraris A.M., Gaetani G.F. Mechanisms of protection of catalase by NADPH. Kinetics and stoichiometry. J Biol Chem. 1999;274:13908–13914. PubMed

Lardinois O.M., Rouxhet P.G. Peroxidatic degradation of azide by catalase and irreversible enzyme activation. Biochem Biophys Acta. 1996;1298:180–190. PubMed

Putnam C.H.D., Arvai A.S., Bourne Y., Tainer J.A. Active and inhibited human catalase structures: ligand and NADPH binding and catalytic mechanism. J Mol Biol. 2000;296:295–309. PubMed

Hayes J.D., Mclellan L.I. Glutathione and glutathione-dependent enzymes represent a co-ordinately regulated defence against oxidative stress. Free Radic Res. 1999;31:273–300. PubMed

Arner E.S. Selenoproteins — what unique properties can arise with selenocysteine in place of cysteine? Exp Cell Res. 2010;316:1296–1303. PubMed

Aprioku J.S. Pharmacology of free radicals and the impact of reactive oxygen species on the testis. J Reprod Infertil. 2013;14:158–172. PubMed PMC

Paiva C.N., Bozza M.T. Are reactive oxygen species always detrimental to pathogens? Antioxid Redox Signal. 2014;20:1001–1012. PubMed PMC

Michiels C. Physiological and pathological responses to hypoxia. Am J Pathol. 2004;164:1875–1882. PubMed PMC

Reis K.A., Guz G., Ozdemir H., Erten Y., Atalay V., Bicik Z. Intravenous iron therapy as a possible risk factor for atherosclerosis in end-stage renal disease. Int Heart J. 2005;46:255–264. PubMed

Bossmann S.H., Oliveros E., Kantor M., Niebler S., Bonfill A., Shahin N. New insights into the mechanisms of the thermal Fenton reactions occurring using different iron(II)-complexes. Water Sci Technol. 2004;49:75–80. PubMed

Bochi G.V., Torbitz V.D., Cargnin L.P., de Carvalho J.A., Gomes P., Moresco R.N. An alternative pathway through the Fenton reaction for the formation of advanced oxidation protein products, a new class of inflammatory mediators. Inflammation. 2014;37:512–521. PubMed

Lü J.M., Nurko J., Weakley S.M., Jiang J., Kougias P., Lin P.H. Molecular mechanisms and clinical applications of nordihydroguaiaretic acid (NDGA) and its derivatives: an update. Med Sci Monit. 2010;16:RA93–RA100. PubMed PMC

Galano A., Macías-Ruvalcaba N.A., Medina Campos O.N., Pedraza-Chaverri J. Mechanism of the OH radical scavenging activity of nordihydroguaiaretic acid: a combined theoretical and experimental study. J Phys Chem B. 2010;114:6625–6635. PubMed

Hwu J.R., Hsu C.I., Hsu M.H., Liang Y.C., Huang R.C., Lee Y.C. Glycosylated nordihydroguaiaretic acids as anti-cancer agents. Bioorg Med Chem Lett. 2011;21:380–382. PubMed

Jourd’heuil D., Jourd’heuil F.L., Kutchukian P.S., Musah R.A., Wink D.A., Grisham M.B. Reaction of superoxide and nitric oxide with peroxynitrite. Implications for peroxynitrite-mediated oxidation reactions in vivo. J Biol Chem. 2001;276:28799–28805. PubMed

Coddington J.W., Hurst J.K., Lymar S.V. Hydroxy radical formation during peroxinotrous acid decomposition. J Am Chem Soc. 1999;121:2438–2443.

Goldstein S., Czapski G. Reactivity of peroxinitrite versus simultaneous generation of (*) NO and O(2) (*) (–) toward NADH. Chem Res Toxicol. 2000;13:736–741. PubMed

Kuzkaya N., Weissmann N., Harrison D.G., Dikalo S. Interactions of peroxynitrite with uric acid in the presence of ascorbate and thiols: implications for uncoupling endothelial nitric oxide synthase. Biochem Pharmacol. 2005;70:343–354. PubMed

Jozefczak M., Remans T., Vangronsveld J., Cuypers A. Glutathione is a key player in metal-induced oxidative stress defenses. Int J Mol Sci. 2012;13:3145–3175. PubMed PMC

Ribeiro M., Rosenstock T.R., Cunha-Oliveira T., Ferreira L.I., Oliveira C.R., Rego A.C. Glutathione redox cycle dysregulation in Huntington's disease knock-in striatal cells. Free Radic Biol Med. 2012;53:1857–1867. PubMed

Townsend D.M., Tew K.D., Tapiero H. The importance of glutathione in human disease. Biomed Pharmacother. 2003;57:145–155. PubMed PMC

Dickinson D.A., Forman H.J. Cellular glutathione and thiols metabolism. Biochem Pharmacol. 2002;64:1019–1026. PubMed

Wu G., Fang Y.Z., Yang S., Luoton J.R., Turner N.D. Glutathione metabolism and its implications for health. J Nutr. 2004;134:489–492. PubMed

Ballatori N., Krance S.M., Notenboom S., Shi S., Tieu K., Hammond C.H.L. Glutathione dysregulation and the etiology and progression of human diseases. Biol Chem. 2009;390:191–214. PubMed PMC

Yan J., Ralston M.M., Meng X., Bongiovanni K.D., Jones A.L., Benndorf R. Glutathione reductase is essential for host defense against bacterial infection. Free Radic Biol Med. 2013;61:320–332. PubMed PMC

Berkholz D.S., Faber H.R., Savvides S.N., Karplus P.A. Catalytic cycle of humane glutathione reductase near 1 A resolution. J Mol Biol. 2008;382:371–384. PubMed PMC

Outten C.E., Cullota V.C. Alternative start sites in Sacharomycetes cerevisiae GLR1 gene are responsible for mitochondrial and cytosolic isoforms of glutathione reductase. J Biol Chem. 2004;279:7785–7791. PubMed PMC

Lesgards J.F., Gauthier C., Iovanna J., Vidal N., Dolla A., Stocker P. Effect of reactive oxygen and carbonyl species on crucial cellular antioxidant enzymes. Chem Biol Interact. 2011;190:28–34. PubMed

Hadjigogos K. The role of free radicals in the pathogenesis of rheumatoid arthritis. Panminerva Med. 2003;45:7–13. PubMed

Rasheed Z. Hydroxyl radical damaged Immunoglobulin G in patients with rheumatoid arthritis: biochemical and immunological studies. Clin Biochem. 2008;41:663–669. PubMed

Sun Y. Free radicals, antioxidant enzymes, and carcinogenesis. Free Radic Biol Med. 1990;8:583–599. PubMed

Colis L.C., Raychaudhury P., Basu A.K. Mutational specificity of γ-radiation-induced guanine–thymine and thymine–guanine intrastrand cross-links in mammalian cells and translesion synthesis past the guanine–thymine lesion by human DNA polymerase η. Biochemistry. 2008;47:8070–8079. PubMed PMC

Turko I.V., Marcondes S., Murad F. Diabetes-associated nitration of tyrosine and inactivation of succinyl-CoA:3-oxoacid CoA-transferase. Am J Physiol Heart Circul Physiol. 2001;281:H2289–H2294. PubMed

Matough F.A., Budin S.B., Hamid Z.A., Alwahaibi N., Mohamed J. The role of oxidative stress and antioxidants in diabetic complications. Sultan Qaboos Univ Med J. 2012;12:5–18. PubMed PMC

Uttara B., Singh A.V., Zamboni P., Mahajan R.T. Oxidative stress and neurodegenerative diseases: a review of upstream and downstream antioxidant therapeutic options. Curr Neuropharmacol. 2009;7:65–74. PubMed PMC

Murphy M.P., LeVine H. Alzheimer's disease and the β-amyloid peptide. J Alzheimers Dis. 2010;19:311. PubMed PMC

Stefanis L. α-Synuclein in Parkinson's disease. Cold Spring Harb Perspect Med. 2012;2:a009399. PubMed PMC

Yamato M., Kudo W., Shiba T., Yamada K.I., Watanabe T., Utsumi H. Determination of reactive oxygen species associated with the degeneration of dopaminergic neurons during dopamine metabolism. Free Radic Res. 2010;44:249–257. PubMed

van Horssen J., Witte M.E., Schreibelt G., de Vries H.E. Radical changes in multiple sclerosis pathogenesis. Biochim Biophys Acta. 2011;1812:141–150. PubMed

Cantu-Medellin N., Kelley E.E. Xanthine oxidoreductase-catalyzed reactive species generation: a process in critical need of reevaluation. Redox Biol. 2013;1:353–358. PubMed PMC

Kim Y.J., Kim E.H., Hahm K.B. Oxidative stress in inflammation-based gastrointestinal tract diseases: challenges and opportunities. J Gastroenterol Hepatol. 2012;27:1004–1010. PubMed

Muriel P. Role of free radicals in liver diseases. Hepatol Int. 2009;3:526–536. PubMed PMC

Leung P.S., Chan Y.C. Role of oxidative stress in pancreatic inflammation. Antioxid Redox Signal. 2009;11:135–165. PubMed

Sreevalsan S., Safe S. Reactive oxygen species and colorectal cancer. Curr Colorectal Cancer Rep. 2013;9:350–357. PubMed PMC

Otamiri T., Sjödahl R. Oxygen radicals: their role in selected gastrointestinal disorders. Dig Dis. 1991;9:133–141. PubMed

Kraus T.A., Mayer L. Oral tolerance and inflammatory bowel disease. Curr Opin Gastroenterol. 2005;21:692–696. PubMed

Huang H., Vangay P., McKinlay C.H.E., Knights D. Multi-omics analysis of inflammatory bowel disease. Immunol Lett. 2014;162:62–68. PubMed

Sobczak M., Fabisiak A., Murawska N., Wesołowska E., Wierzbicka P., Wlazłowski M. Current overview of extrinsic and intrinsic factors in etiology and progression of inflammatory bowel diseases. Pharmacol Rep. 2014;66:766–775. PubMed

Jones-Hall Y.L., Grisham M.B. Imunopathological charakterization of selected mouse models of inflammatory bowel disease: comparison to human disease. Pathophysiology. 2014;21:267–288. PubMed

Bandzar S., Gupta S., Platt M.O. Crohn's disease. A review of treatment options and current research. Cell Immunol. 2013;286:45–52. PubMed

Ishihara T., Tanaka K., Tasaka Y., Namba T., Suzuki J., Ishihara T. Therapeutic effect of lecithinized superoxide dismutase against colitis. J Pharmacol Exp Ther. 2009;328:152–164. PubMed

Huang Y., Xiao S., Jiang Q. Role of Rho kinase signal pathway in inflammatory bowel disease. Int J Clin Exp Med. 2015;8:3089–3097. PubMed PMC

Grisham M.B., Granger D.N. Neutrophil-mediated mucosal injury. Role of reactive oxygen metabolites. Dig Dis Sci. 1988;33:6S–15S. PubMed

Martinez F.O., Sica A., Mantovani A., Locati M. Macrophage activation and polarization. Front Biosci. 2008;13:453–461. PubMed

Nathan C., Xie Q.W. Regulation of biosynthesis of nitric oxide. J Biol Chem. 1994;269:13725–13728. PubMed

Kim K.M., Kim P.K.M., Kwon Y.G., Bai S.K., Nam W.D., Kim Y.M. Regulation of apoptosis by nitrosative stress. J Biochem Mol Biol. 2002;35:127–133. PubMed

Hori M., Nobe H., Horiguchi K., Ozaki H. MCP-1 targeting inhibits muscularis macrophage recruitment and intestinal smooth muscle dysfunction in colonic inflammation. Am J Physiol Cell Physiol. 2008;294:C391–C401. PubMed

Rumessen J.J. Ultrasctructure of interstitial cells of Cajal at the colonic submuscular border in patients with ulcerative colitis. Gastroenterology. 1996;111:1447–1455. PubMed

Wang X.Y., Zarate N., Soderholm J.D., Buorgeois J.M., Liu L.W., Huizinga J.D. Ultrasctructural injury to intersticial cells of Cajal and communication with mast cells in Crohn's disease. Neurogastroenterol Motil. 2007;19:349–364. PubMed

Mikkelsen H.B. Interstitial cells of Cajal, Macrophages and mast cells in the gut musculature: morphology, distribution, spatial and possible functional interactions. J Cell Mol Med. 2010;14:818–832. PubMed PMC

Caughey G.H. Mast cell proteases as protective and inflammatory mediators. Adv Exp Med Biol. 2011;716:212–234. PubMed PMC

Brazil J., Louis N., Parkos C. The role of polymorphonuclear leukocyte trafficking in the perpetuation of inflammation during inflammatory bowel disease. Inflamm Bowel Dis. 2013;19:1556–1565. PubMed PMC

Kawakami Y., Okada H., Murakami Y., Kawakami T., Ueda Y., Kunii D. Dietary intake, neutrophil fatty acid profile, serum antioxidant vitamins and oxygen radical absorbance capacity in patients with ulcerative colitis. J Nutr Sci Vitaminol. 2007;53:153–159. PubMed

Alzoghaibi M.A. Concepts of oxidative stress and antioxidant defense in Crohn's disease. World J Gastroenterol. 2013;19:6540–6547. PubMed PMC

Naito Y., Takagi T., Yoshikawa T. Neutrophil-dependent oxidative stress in ulcerative colitis. J Clin Biochem Nutr. 2007;41:18–26. PubMed PMC

Taylor-Clark T.E. Role of reactive oxygen species and TRP channels in the cough reflex. Cell Calcium. 2016 PubMed PMC

Ogawa N., Kurokawa T., Mori Y. Sensing of redox status by TRP channels. Cell Calcium. 2016 PubMed

Holzer P. TRP channels in the digestive system. Curr Pharm Biotechnol. 2011;12:24–34. PubMed PMC

Lakhan S.E., Kirchgessner A. Neuroinflammation in inflammatory bowel disease. J Neuroinflammation. 2010;7:37. PubMed PMC

Lubos E., Loscalzo J., Handy D. Glutathione peroxidase-1 in health and disease: from molecular mechanisms to therapeutic opportunities. Antioxid Redox Signal. 2011;15:1957–1997. PubMed PMC

Piechota-Polanczyk A., Fichna J. Review article: the role of oxidative stress in pathogenesis and treatment of inflammatory bowel diseases. Naunyn Schmiedebergs Arch Pharmacol. 2014;387:605–620. PubMed PMC

Auli M., Nasser Y., Ho W., Burgueno J.F., Keenan C.M., Romero C. Neuromuscular changes in a rat model of colitis. Auton Neurosci. 2008;141:10–21. PubMed

De Giorgio R., Guerrini S., Barbara G., Staghellini V., de Ponti F., Corinaldesi R. Inflammatory neuropathies of the enteric nervous system. Gastroenterology. 2004;126:1872–1883. PubMed

Sanovic S., Lamb D.P., Blennerhassett M.G. Damage to the enteric nervous system in experimental colitis. Am J Pathol. 1999;155:1051–1057. PubMed PMC

Choi K.M., Gibbons S.J., Nguyen T.V., Stolz G.I., Lurken M.S., Ordög T. Heme oxygenase-1 protects intersticial cells of Cajal from oxidative stress and reverses diabetic gastroparesis. Gastroenterology. 2008;135:2055–2064. PubMed PMC

Zarate N., Wang X.Y., Tougas G., Anvari M., Birch D., Mearin F. Intramuscular intersticial cells of Cajal associated with mast cells survive nitrergic nerves in achalasia. Neurogastroenterol Motil. 2006;18:556–568. PubMed

Oliveira S., Queiroga C.S., Vieira H.L. Mitochondria and carbon monoxide: cytoprotection and control of cell metabolism – a role for Ca2+? J Physiol. 2016;594:4131–4138. PubMed PMC

Lauret E., Rodrigo L. Celiac disease and autoimmune-associated conditions. Biomed Res Int. 2013;2013:127589. PubMed PMC

Ferretti G., Bacchetti T., Masciangelo S., Saturni L. Celiac disease, inflammation and oxidative damage: a nutrigenetic approach. Nutrients. 2012;4:243–257. PubMed PMC

Stojiljković V., Todorović A., Pejić S., Kasapović J., Saicić Z.S., Radlović N. Antioxidant status and lipid peroxidation in small intestinal mucosa of children with celiac disease. Clin Biochem. 2009;42:1431–1437. PubMed

Stazi A.V., Trinti B. Selenium deficiency in celiac disease: risk of autoimmune thyroid diseases. Minerva Med. 2008;99:643–653. PubMed

Stojiljković V., Todorović A., Radlović N., Pejić S., Mladenović M., Kasapović J. Antioxidant enzymes, glutathione and lipid peroxidation in peripheral blood of children affected by coeliac disease. Ann Clin Biochem. 2007;44:537–543. PubMed

Pascual V., Dieli-Crimi R., López-Palacios N., Bodas A., Medrano L.M., Núñez C. Inflammatory bowel disease and celiac disease: overlaps and differences. World J Gastroenterol. 2014;20:4846–4856. PubMed PMC

Stojiljković V., Pejić S., Kasapović J., Gavrilović L., Stojiljković S., Nikolić D. Glutathione redox cycle in small intestinal mucosa and peripheral blood of pediatric celiac disease patients. An Acad Bras Cienc. 2012;84:75–84. PubMed

Boda M., Németh I., Boda D. The caffeine metabolic ratio as an index of xanthine oxidase activity in clinically active and silent celiac patients. J Pediatr Gastroenterol Nutr. 1999;29:546–550. PubMed

Pavlick K.P., Laroux F.S., Fuseler J., Wolf R.E., Gray L., Hoffman J. Role of reactive metabolites of oxygen and nitrogen in inflammatory bowel disease. Free Radic Biol Med. 2002;33:311–322. PubMed

Hoffenberg E.J., Deutsch J., Smith S., Sokol R.J. Circulating antioxidant concentrations in children with inflammatory bowel disease. Am J Clin Nutr. 1997;65:1482–1488. PubMed