{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T14:44:37Z","timestamp":1775486677315,"version":"3.50.1"},"reference-count":34,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2025,7,2]],"date-time":"2025-07-02T00:00:00Z","timestamp":1751414400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"NIH","doi-asserted-by":"publisher","award":["K23DK128634"],"award-info":[{"award-number":["K23DK128634"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"NIH","doi-asserted-by":"publisher","award":["DK104344"],"award-info":[{"award-number":["DK104344"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"NIH","doi-asserted-by":"publisher","award":["P30DK040561"],"award-info":[{"award-number":["P30DK040561"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>We aimed to examine the effect of zonulin and zonulin inhibition on gastrointestinal (GI) motility and the mRNA expression of zonulin and the protease-activated receptor 2 (par2), the primary receptor for zonulin, under conditions of inflammation by lipopolysaccharide (LPS) injection. The experimental models included zonulin transgenic mice (ztm), par2 knockout ztm (ztm-par2 \u2212\/\u2212), ztm exposed to the zonulin inhibitor AT1001 (ztm-AT1001), and wildtype mouse controls. GI transit was measured by fluorescein isothiocyanate-dextran and mRNA expression by real-time quantitative polymerase chain reaction in whole, and in epithelial and non-epithelial tissues of all GI segments. There were no differences in the GI transit between mouse groups at baseline. After the LPS injection, ztm mice had an attenuated slowing of the GI transit compared to wildtype mice. The zonulin-inhibited mice had motility patterns similar to wildtype mice. zonulin upregulation was noted in GI segments of the ztm, ztm-par2 \u2212\/\u2212, and ztm-AT1001 after the LPS injection. Differences in motility patterns between ztm and zonulin inhibition models despite zonulin expression in GI segments of all mouse groups supports that PAR2 is key for zonulin\u2019s effect on motility under conditions of inflammation. However, the findings from the epithelial and non-epithelial compartments suggest that the pathway of activity is complex and likely indirect.<\/jats:p>","DOI":"10.3390\/ijms26136381","type":"journal-article","created":{"date-parts":[[2025,7,2]],"date-time":"2025-07-02T09:08:44Z","timestamp":1751447324000},"page":"6381","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Characterizing zonulin and par2 Expression in Zonulin Transgenic and Zonulin Inhibition Mouse Models of Motility and Inflammation"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4767-8495","authenticated-orcid":false,"given":"Enid E.","family":"Martinez","sequence":"first","affiliation":[{"name":"Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children\u2019s Hospital, Boston, MA 02115, USA"},{"name":"Mucosal Immunology and Biology Research Center, Department of Pediatrics, Massachusetts General Brigham for Children, Boston, MA 02129, USA"},{"name":"Harvard Medical School, Harvard University, Boston, MA 02115, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jordan D.","family":"Philpott","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children\u2019s Hospital, Boston, MA 02115, USA"},{"name":"Mucosal Immunology and Biology Research Center, Department of Pediatrics, Massachusetts General Brigham for Children, Boston, MA 02129, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jinggang","family":"Lan","sequence":"additional","affiliation":[{"name":"Mucosal Immunology and Biology Research Center, Department of Pediatrics, Massachusetts General Brigham for Children, Boston, MA 02129, USA"},{"name":"Department of Pediatrics, Division of Pediatric Gastroenterology and Nutrition, Mass General Brigham for Children, Boston, MA 02114, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"K. Marco","family":"Rodriguez Hovnanian","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children\u2019s Hospital, Boston, MA 02115, USA"},{"name":"Mucosal Immunology and Biology Research Center, Department of Pediatrics, Massachusetts General Brigham for Children, Boston, MA 02129, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2134-0261","authenticated-orcid":false,"given":"Alessio","family":"Fasano","sequence":"additional","affiliation":[{"name":"Mucosal Immunology and Biology Research Center, Department of Pediatrics, Massachusetts General Brigham for Children, Boston, MA 02129, USA"},{"name":"Harvard Medical School, Harvard University, Boston, MA 02115, USA"},{"name":"Department of Pediatrics, Division of Pediatric Gastroenterology and Nutrition, Mass General Brigham for Children, Boston, MA 02114, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"141","DOI":"10.1038\/nri3608","article-title":"Intestinal epithelial cells: Regulators of barrier function and immune homeostasis","volume":"14","author":"Peterson","year":"2014","journal-title":"Nat. Rev. Immunol."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Bubeck, M., Becker, C., and Patankar, J.V. (2023). Guardians of the gut: Influence of the enteric nervous system on the intestinal epithelial barrier. Front. Med., 10.","DOI":"10.3389\/fmed.2023.1228938"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"e970936","DOI":"10.4161\/21688362.2014.970936","article-title":"Metabolic regulation of intestinal epithelial barrier during inflammation","volume":"3","author":"Colgan","year":"2015","journal-title":"Tissue Barriers"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"290","DOI":"10.1097\/MCC.0000000000001175","article-title":"The enteroendocrine axis and its effect on gastrointestinal function, nutrition, and inflammation","volume":"30","author":"Philpott","year":"2024","journal-title":"Curr. Opin. Crit. Care"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"e424","DOI":"10.1097\/PCC.0000000000002985","article-title":"The Zonulin Pathway as a Potential Mediator of Gastrointestinal Dysfunction in Critical Illness","volume":"23","author":"Martinez","year":"2022","journal-title":"Pediatr. Crit. Care Med."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Buckley, A., and Turner, J.R. (2018). Cell Biology of Tight Junction Barrier Regulation and Mucosal Disease. Cold Spring Harb. Perspect. Biol., 10.","DOI":"10.1101\/cshperspect.a029314"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"628157","DOI":"10.1155\/2015\/628157","article-title":"Intestinal Permeability in Inflammatory Bowel Disease: Pathogenesis, Clinical Evaluation, and Therapy of Leaky Gut","volume":"2015","author":"Michielan","year":"2015","journal-title":"Mediat. Inflamm."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1165","DOI":"10.3748\/wjg.v20.i5.1165","article-title":"Intestinal barrier in inflammatory bowel disease","volume":"20","author":"Antoni","year":"2014","journal-title":"World J. Gastroenterol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"749","DOI":"10.1002\/JLB.5MR0120-230R","article-title":"Tight junctions in the development of asthma, chronic rhinosinusitis, atopic dermatitis, eosinophilic esophagitis, and inflammatory bowel diseases","volume":"107","author":"Sugita","year":"2020","journal-title":"J. Leukoc. Biol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"66","DOI":"10.1016\/S2468-1253(22)00241-2","article-title":"The intestinal barrier in disorders of the central nervous system","volume":"8","author":"Pellegrini","year":"2023","journal-title":"Lancet Gastroenterol. Hepatol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"428","DOI":"10.1128\/iai.60.2.428-434.1992","article-title":"Cloning of a gene (zot) encoding a new toxin produced by Vibrio cholerae","volume":"60","author":"Baudry","year":"1992","journal-title":"Infect. Immun."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"16799","DOI":"10.1073\/pnas.0906773106","article-title":"Identification of human zonulin, a physiological modulator of tight junctions, as prehaptoglobin-2","volume":"106","author":"Tripathi","year":"2009","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1096\/fj.10-158972","article-title":"The active Zot domain (aa 288\u2013293) increases ZO-1 and myosin 1C serine\/threonine phosphorylation, alters interaction between ZO-1 and its binding partners, and induces tight junction disassembly through proteinase activated receptor 2 activation","volume":"25","author":"Goldblum","year":"2011","journal-title":"FASEB J."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1443","DOI":"10.2337\/db05-1593","article-title":"Zonulin upregulation is associated with increased gut permeability in subjects with type 1 diabetes and their relatives","volume":"55","author":"Sapone","year":"2006","journal-title":"Diabetes"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"e149633","DOI":"10.1172\/JCI149633","article-title":"Multisystem inflammatory syndrome in children is driven by zonulin-dependent loss of gut mucosal barrier","volume":"131","author":"Yonker","year":"2021","journal-title":"J. Clin. Investig."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"130","DOI":"10.1111\/nyas.13343","article-title":"Zonulin transgenic mice show altered gut permeability and increased morbidity\/mortality in the DSS colitis model","volume":"1397","author":"Sturgeon","year":"2017","journal-title":"Ann. N. Y. Acad. Sci."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"408","DOI":"10.1080\/00365520500235334","article-title":"Gliadin, zonulin and gut permeability: Effects on celiac and non-celiac intestinal mucosa and intestinal cell lines","volume":"41","author":"Drago","year":"2006","journal-title":"Scand. J. Gastroenterol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"107","DOI":"10.11613\/BM.2013.013","article-title":"Increased plasma zonulin in patients with sepsis","volume":"23","author":"Klaus","year":"2013","journal-title":"Biochem. Medica"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Martinez, E.E., Lan, J., Konno, T., Miranda-Ribera, A., Fiorentino, M., Mehta, N.M., and Fasano, A. (2021). Novel role of zonulin in the pathophysiology of gastro-duodenal transit: A clinical and translational study. Sci. Rep., 11.","DOI":"10.1038\/s41598-021-01879-y"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1186\/s12959-019-0194-8","article-title":"Protease-activated receptors (PARs): Mechanisms of action and potential therapeutic modulators in PAR-driven inflammatory diseases","volume":"17","author":"Heuberger","year":"2019","journal-title":"Thromb. J."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"717","DOI":"10.1152\/physrev.00044.2021","article-title":"Protease-activated receptors in health and disease","volume":"103","author":"Peach","year":"2023","journal-title":"Physiol. Rev."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"257","DOI":"10.1046\/j.1365-2036.2000.00690.x","article-title":"Review article: Proteinase-activated receptors\u2014Novel signals for gastrointestinal pathophysiology","volume":"14","author":"Vergnolle","year":"2000","journal-title":"Aliment. Pharmacol. Ther."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1213","DOI":"10.1038\/sj.bjp.0704211","article-title":"In vivo evidence that protease-activated receptors 1 and 2 modulate gastrointestinal transit in the mouse","volume":"133","author":"Kawabata","year":"2001","journal-title":"Br. J. Pharmacol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"S230","DOI":"10.1038\/sj.bjp.0707491","article-title":"Gastrointestinal roles for proteinase-activated receptors in health and disease","volume":"153","author":"Kawabata","year":"2008","journal-title":"Br. J. Pharmacol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"950","DOI":"10.1016\/j.lfs.2005.06.035","article-title":"Mechanisms for modulation of mouse gastrointestinal motility by proteinase-activated receptor (PAR)-1 and -2 in vitro","volume":"78","author":"Sekiguchi","year":"2006","journal-title":"Life Sci."},{"key":"ref_26","first-page":"19160","article-title":"Zonula occludens toxin structure-function analysis. Identification of the fragment biologically active on tight junctions and of the zonulin receptor binding domain","volume":"276","author":"Lu","year":"2001","journal-title":"J. Biol. Chem."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"2916","DOI":"10.1073\/pnas.0500178102","article-title":"Role of the intestinal tight junction modulator zonulin in the pathogenesis of type I diabetes in BB diabetic-prone rats","volume":"102","author":"Watts","year":"2005","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Miranda-Ribera, A., Ennamorati, M., Serena, G., Cetinbas, M., Lan, J., Sadreyev, R.I., Jain, N., Fasano, A., and Fiorentino, M. (2019). Exploiting the Zonulin Mouse Model to Establish the Role of Primary Impaired Gut Barrier Function on Microbiota Composition and Immune Profiles. Front. Immunol., 10.","DOI":"10.3389\/fimmu.2019.02233"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"177","DOI":"10.2353\/ajpath.2006.051098","article-title":"Protective effect of proteinase-activated receptor 2 activation on motility impairment and tissue damage induced by intestinal ischemia\/reperfusion in rodents","volume":"169","author":"Cattaruzza","year":"2006","journal-title":"Am. J. Pathol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"300","DOI":"10.1016\/j.cell.2014.04.050","article-title":"Crosstalk between muscularis macrophages and enteric neurons regulates gastrointestinal motility","volume":"158","author":"Muller","year":"2014","journal-title":"Cell"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"961","DOI":"10.1093\/intimm\/dxn055","article-title":"Induction of pro-inflammatory programs in enteroendocrine cells by the Toll-like receptor agonists flagellin and bacterial LPS","volume":"20","author":"Selleri","year":"2008","journal-title":"Int. Immunol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"134","DOI":"10.1161\/01.ATV.0000251020.24399.a2","article-title":"Haptoglobin genotype is a determinant of iron, lipid peroxidation, and macrophage accumulation in the atherosclerotic plaque","volume":"27","author":"Levy","year":"2007","journal-title":"Arterioscler. Thromb. Vasc. Biol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1342","DOI":"10.1182\/blood-2003-09-3051","article-title":"Role of tissue factor and protease-activated receptors in a mouse model of endotoxemia","volume":"103","author":"Pawlinski","year":"2004","journal-title":"Blood"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Shrum, B., Anantha, R.V., Xu, S.X., Donnelly, M., Haeryfar, S.M., McCormick, J.K., and Mele, T. (2014). A robust scoring system to evaluate sepsis severity in an animal model. BMC Res. Notes, 7.","DOI":"10.1186\/1756-0500-7-233"}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/26\/13\/6381\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T18:03:16Z","timestamp":1760032996000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/26\/13\/6381"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,7,2]]},"references-count":34,"journal-issue":{"issue":"13","published-online":{"date-parts":[[2025,7]]}},"alternative-id":["ijms26136381"],"URL":"https:\/\/doi.org\/10.3390\/ijms26136381","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,7,2]]}}}