{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T13:47:49Z","timestamp":1785764869248,"version":"3.56.0"},"reference-count":45,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2026,8,1]],"date-time":"2026-08-01T00:00:00Z","timestamp":1785542400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Science, Technological Development, and Innovation","award":["451-03-33\/2026-03\/200007"],"award-info":[{"award-number":["451-03-33\/2026-03\/200007"]}]},{"award":["451-03-33\/2026-03\/200007"],"award-info":[{"award-number":["451-03-33\/2026-03\/200007"]}],"id":[{"id":"https:\/\/ror.org\/01znas443","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Int. J. Mol. Sci.","IJMS"],"abstract":"<jats:p>Redox homeostasis is driven by the ratio of the concentrations of cellular redox couples. The aim of this study was to reduce 2GSH\/GSSG turnover in an ex vivo ileum by the irreversible inhibition of glutathione reductase (GR) activity (by BCNU) and evaluate its effects on contractility, antioxidant enzyme activity, and thiol levels. Increasing concentrations of BCNU as well as a single EC50 BCNU dose significantly reduced both contraction amplitude and GR activity. The addition of cumulative doses of both GSH and GSSG after EC50 BCNU caused further dose-dependent amplitude reduction, but turned GR activity to control levels and reduced CuZn-superoxide dismutase activity; cumulative doses of GSH also decreased catalase activity. Both GSH and GSSG cumulative doses decreased the contractility of non-treated control ileum in a dose-dependent manner, while GSH also increased glutathione peroxidase (GPx) activity. The correlation analysis showed a negative relationship between contractility and non-protein thiols, and positive correlations between catalase and GPx activities in BCNU treated ileum, as well as between GPx and non-protein thiols in solvent controls. The results present a framework for how glutathione turnover and ileum contractility are linked.<\/jats:p>","DOI":"10.3390\/ijms27156920","type":"journal-article","created":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T12:57:56Z","timestamp":1785761876000},"page":"6920","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Role of Cellular Glutathione Redox Cycle and Glutathione in the Regulation of Ileum Contractility"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5906-3298","authenticated-orcid":false,"given":"Tanja","family":"Grahovac","sequence":"first","affiliation":[{"name":"Department of Physiology, Institute for Biological Research \u201cSini\u0161a Stankovi\u0107\u201d\u2014National Institute of the Republic of Serbia, University of Belgrade, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2772-0134","authenticated-orcid":false,"given":"Zorana","family":"Ore\u0161\u010danin Du\u0161i\u0107","sequence":"additional","affiliation":[{"name":"Department of Physiology, Institute for Biological Research \u201cSini\u0161a Stankovi\u0107\u201d\u2014National Institute of the Republic of Serbia, University of Belgrade, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1116-2035","authenticated-orcid":false,"given":"Aleksandra","family":"Nikoli\u0107-Koki\u0107","sequence":"additional","affiliation":[{"name":"Department of Physiology, Institute for Biological Research \u201cSini\u0161a Stankovi\u0107\u201d\u2014National Institute of the Republic of Serbia, University of Belgrade, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6338-2833","authenticated-orcid":false,"given":"Du\u0161ko","family":"Blagojevi\u0107","sequence":"additional","affiliation":[{"name":"Department of Physiology, Institute for Biological Research \u201cSini\u0161a Stankovi\u0107\u201d\u2014National Institute of the Republic of Serbia, University of Belgrade, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3700-688X","authenticated-orcid":false,"given":"Teodora","family":"Vidonja Uzelac","sequence":"additional","affiliation":[{"name":"Department of Physiology, Institute for Biological Research \u201cSini\u0161a Stankovi\u0107\u201d\u2014National Institute of the Republic of Serbia, University of Belgrade, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1191","DOI":"10.1016\/S0891-5849(01)00480-4","article-title":"Redox environment of the cell as viewed through the redox state of the glutathione disulfide\/glutathione couple","volume":"30","author":"Schafer","year":"2001","journal-title":"Free Radic. Biol. Med."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"734","DOI":"10.1089\/ars.2015.6247","article-title":"The redox code","volume":"23","author":"Jones","year":"2015","journal-title":"Antioxid. Redox Signal."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2225","DOI":"10.1006\/jmcc.1997.0461","article-title":"Cytoplasmic redox potential affects energetics and contractile reactivity of vascular smooth muscle","volume":"29","author":"Barron","year":"1997","journal-title":"J. Mol. Cell. Cardiol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1253","DOI":"10.1242\/jeb.203.8.1253","article-title":"Mammalian oxygen sensing, signalling and gene regulation","volume":"203","author":"Wenger","year":"2000","journal-title":"J. Exp. Biol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"936","DOI":"10.1016\/S0891-5849(99)00175-6","article-title":"Gene expression and the thiol redox state","volume":"27","author":"Arrigo","year":"1999","journal-title":"Free Radic. Biol. Med."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"L492","DOI":"10.1152\/ajplung.2000.278.3.L492","article-title":"O2-evoked regulation of HIF-1\u03b1 and NF-\u03baB in perinatal lung epithelium requires glutathione biosynthesis","volume":"278","author":"Haddad","year":"2000","journal-title":"Am. J. Physiol. Lung Cell. Mol. Physiol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"21130","DOI":"10.1074\/jbc.M000737200","article-title":"Antioxidant\/pro-oxidant equilibrium regulates HIF-1\u03b1 and NF-\u03baB redox sensitivity: Evidence for inhibition by glutathione oxidation in alveolar epithelial cells","volume":"275","author":"Haddad","year":"2000","journal-title":"J. Biol. Chem."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Radzinski, M., Oppenheim, T., Metanis, N., and Reichmann, D. (2021). The Cys sense: Thiol redox switches mediate life cycles of cellular proteins. Biomolecules, 11.","DOI":"10.3390\/biom11030469"},{"key":"ref_9","first-page":"1080","article-title":"Severe generalized glutathione reductase deficiency after antitumor chemotherapy with BCNU (1,3-bis(chloroethyl)-1-nitrosourea)","volume":"89","author":"Frischer","year":"1977","journal-title":"J. Lab. Clin. Med."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"754","DOI":"10.1016\/0006-291X(78)91053-7","article-title":"Inactivation of glutathione reductase by 2-chloroethyl nitrosourea-derived isocyanates","volume":"83","author":"Babson","year":"1978","journal-title":"Biochem. Biophys. Res. Commun."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1016\/0378-4274(83)90036-X","article-title":"The effect of BCNU (carmustine) on tissue glutathione reductase activity","volume":"17","author":"Kehrer","year":"1983","journal-title":"Toxicol. Lett."},{"key":"ref_12","first-page":"355","article-title":"The effects of BCNU (1,3-bis(2-chloroethyl)-1-nitrosourea) and CCNU (1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea) on glutathione reductase and other enzymes in mouse tissue","volume":"40","author":"Maker","year":"1983","journal-title":"Res. Commun. Chem. Pathol. Pharmacol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"3317","DOI":"10.1016\/0006-2952(88)90645-4","article-title":"Characterization of the inhibition of glutathione reductase and the recovery of enzyme activity in exponentially growing murine leukemia (L1210) cells treated with 1,3-bis(2-chloroethyl)-1-nitrosourea","volume":"37","author":"Cohen","year":"1988","journal-title":"Biochem. Pharmacol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1853","DOI":"10.2147\/CCID.S378470","article-title":"Augmented glutathione absorption from oral mucosa and its effect on skin pigmentation: A clinical review","volume":"15","author":"Sharma","year":"2022","journal-title":"Clin. Cosmet. Investig. Dermatol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"fnad116","DOI":"10.1093\/femsle\/fnad116","article-title":"Effect of long-term oral glutathione supplementation on gut microbiome of type 2 diabetic individuals","volume":"370","author":"Gaike","year":"2023","journal-title":"FEMS Microbiol. Lett."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"3671","DOI":"10.1111\/bph.13161","article-title":"Chloride channels mediate sodium sulphide-induced relaxation in rat uteri","volume":"172","year":"2015","journal-title":"Br. J. Pharmacol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1016\/j.pharep.2013.12.012","article-title":"Comparison of the effects of methanethiol and sodium sulphide on uterine contractile activity","volume":"66","year":"2014","journal-title":"Pharmacol. Rep."},{"key":"ref_18","first-page":"132","article-title":"Redox regulation of cellular functions","volume":"72","author":"Oktyabrsky","year":"2007","journal-title":"Biochemistry"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"4928","DOI":"10.1046\/j.1432-1327.2000.01601.x","article-title":"Regulation of protein function by S-glutathiolation in response to oxidative and nitrosative stress","volume":"267","author":"Klatt","year":"2000","journal-title":"Eur. J. Biochem."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"711","DOI":"10.1146\/annurev.bi.52.070183.003431","article-title":"Glutathione","volume":"52","author":"Meister","year":"1983","journal-title":"Annu. Rev. Biochem."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"631","DOI":"10.1016\/0306-3623(87)90036-X","article-title":"The effect of ethanol on spontaneous contractions and on the contraction produced by periarterial nerve stimulation and by acetylcholine in the rat isolated ileum","volume":"18","author":"Wali","year":"1987","journal-title":"Gen. Pharmacol. Vasc. Syst."},{"key":"ref_22","unstructured":"National Library of Medicine, National Center for Biotechnological Information, and Pub(C)hem (2026, June 09). Carmustine, Available online: https:\/\/pubchem.ncbi.nlm.nih.gov\/compound\/Carmustine."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1016\/j.ejphar.2004.06.043","article-title":"The glutathione reductase inhibitor carmustine induces an influx of Ca2+ in PC12 cells","volume":"497","author":"Doroshenko","year":"2004","journal-title":"Eur. J. Pharmacol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"185","DOI":"10.1016\/S0014-2999(03)02191-5","article-title":"Ion dependence of cytotoxicity of carmustine against PC12 cells","volume":"476","author":"Doroshenko","year":"2003","journal-title":"Eur. J. Pharmacol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1113\/jphysiol.1996.sp021572","article-title":"Oxidized glutathione mediates cation channel activation in calf vascular endothelial cells during oxidant stress","volume":"495","author":"Koliwad","year":"1996","journal-title":"J. Physiol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1016\/S0021-9258(19)40201-9","article-title":"Carmustine augments the effects of tert-butyl hydroperoxide on calcium signaling in cultured pulmonary artery endothelial cells","volume":"265","author":"Elliott","year":"1990","journal-title":"J. Biol. Chem."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1083\/jcb.200110056","article-title":"PECAM-1 (CD31) regulates a hydrogen peroxide-activated nonselective cation channel in endothelial cells","volume":"157","author":"Ji","year":"2002","journal-title":"J. Cell Biol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1932","DOI":"10.1111\/j.1476-5381.2009.00490.x","article-title":"Hydrogen peroxide affects contractile activity and anti-oxidant enzymes in rat uterus","volume":"158","author":"Appiah","year":"2009","journal-title":"Br. J. Pharmacol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1038\/369289a0","article-title":"Inactivation properties of voltage-gated K+ channels altered by presence of beta-subunit","volume":"369","author":"Rettig","year":"1994","journal-title":"Nature"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"28311","DOI":"10.1074\/jbc.271.45.28311","article-title":"Comparison of binding and block produced by alternatively spliced Kv1 subunits","volume":"27","author":"Wang","year":"1996","journal-title":"J. Biol. Chem."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1404","DOI":"10.1152\/ajpheart.00696.2006","article-title":"H2O2 activates redox- and 4-aminopyridine-sensitive Kv channels in coronary vascular smooth muscle","volume":"292","author":"Rogers","year":"2007","journal-title":"Am. J. Physiol. Heart Circ. Physiol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1167","DOI":"10.1038\/cdd.2009.37","article-title":"Glutathione disulfide induces neural cell death via a 12-lipoxygenase pathway","volume":"16","author":"Park","year":"2009","journal-title":"Cell Death Differ."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"960","DOI":"10.1016\/0006-291X(90)90904-2","article-title":"Glutathione disulfide enhances the reduced glutathione inhibition of lipid peroxidation in rat liver microsomes","volume":"166","author":"Scholz","year":"1990","journal-title":"Biochem. Biophys. Res. Commun."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"112","DOI":"10.1016\/j.abb.2005.07.007","article-title":"The modulation of thiol redox state affects the production and metabolism of hydrogen peroxide by heart mitochondria","volume":"441","author":"Rigobello","year":"2005","journal-title":"Arch. Biochem. Biophys."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1749","DOI":"10.1089\/ars.2012.5041","article-title":"Polysulfides link H2S to protein thiol oxidation","volume":"19","author":"Greiner","year":"2013","journal-title":"Antioxid. Redox Signal."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"101867","DOI":"10.1016\/j.redox.2021.101867","article-title":"Oxidative eustress: On constant alert for redox homeostasis","volume":"41","author":"Sies","year":"2021","journal-title":"Redox Biol."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"351","DOI":"10.1016\/j.tibs.2004.05.005","article-title":"Microbial H2O2 sensors as archetypical redox signaling modules","volume":"29","author":"Toledano","year":"2004","journal-title":"Trends Biochem. Sci."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1146\/annurev.pharmtox.44.101802.121735","article-title":"Protein sulfenic acids in redox signaling","volume":"44","author":"Poole","year":"2004","journal-title":"Annu. Rev. Pharmacol. Toxicol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1016\/S0021-9258(19)52451-6","article-title":"Protein measurement with Folin phenol reagent","volume":"193","author":"Lowry","year":"1951","journal-title":"J. Biol. Chem."},{"key":"ref_40","unstructured":"Beutler, E. (1982). Red Cell Metabolism: A Manual of Biochemical Methods, Grune & Stratton. [3rd ed.]."},{"key":"ref_41","first-page":"74","article-title":"Studies on the quantitative and qualitative characterization of erythrocyte glutathione peroxidase","volume":"70","author":"Paglia","year":"1967","journal-title":"J. Lab. Clin. Med."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"665","DOI":"10.1007\/BF01921531","article-title":"Glutathione reductase test with whole blood, a convenient procedure for the assessment of the riboflavin status in humans","volume":"30","author":"Glatzle","year":"1974","journal-title":"Experientia"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"3170","DOI":"10.1016\/S0021-9258(19)45228-9","article-title":"The role of superoxide anion in the autoxidation of epinephrine and a simple assay for superoxide dismutase","volume":"247","author":"Misra","year":"1972","journal-title":"J. Biol. Chem."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"70","DOI":"10.1016\/0003-9861(59)90090-6","article-title":"Tissue sulfhydryl groups","volume":"82","author":"Ellman","year":"1959","journal-title":"Arch. Biochem. Biophys."},{"key":"ref_45","unstructured":"Hinkle, D.E., Wiersma, W., and Jurs, S.G. (2002). Applied Statistics for the Behavioral Sciences, Houghton Mifflin. [5th ed.]."}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/27\/15\/6920\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T13:06:15Z","timestamp":1785762375000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/27\/15\/6920"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,1]]},"references-count":45,"journal-issue":{"issue":"15","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["ijms27156920"],"URL":"https:\/\/doi.org\/10.3390\/ijms27156920","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,1]]}}}