{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,23]],"date-time":"2026-01-23T15:05:36Z","timestamp":1769180736672,"version":"3.49.0"},"reference-count":26,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,22]],"date-time":"2026-01-22T00:00:00Z","timestamp":1769040000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"Ministry of Education","doi-asserted-by":"publisher","award":["2021R1F1A1056645 (RS-2021-NR063002)"],"award-info":[{"award-number":["2021R1F1A1056645 (RS-2021-NR063002)"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"Ministry of Education","doi-asserted-by":"publisher","award":["2023R1A2C1004538 (RS-2023-NR076554)"],"award-info":[{"award-number":["2023R1A2C1004538 (RS-2023-NR076554)"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Laryngopharyngeal reflux disease (LPRD) results from the retrograde flow of gastric contents into the upper aerodigestive tract, causing epithelial injury. Progress in its management has been limited by the lack of objective biomarkers and reproducible in vivo models. This study aimed to establish a chronic, non-surgical mouse model of LPRD and to investigate the protective effect of N-acetylcysteine (NAC). Female C57BL\/6 mice were randomly assigned to three groups: control (standard drinking water), study (acidified water, pH 3.0, for 12 weeks), and treatment (acidified water for 12 weeks plus NAC supplementation during the final 4 weeks). Body weight, food intake, and water consumption were monitored weekly. Pharyngeal tissues were analyzed by immunohistochemistry and Western blotting. Chronic acid exposure resulted in loss of membrane-localized E-cadherin, cytoplasmic redistribution, and upregulation of matrix metalloproteinase-7 (MMP-7). These molecular alterations were accompanied by enhanced phosphorylation of ERK and c-Jun, consistent with activation of the ROS\u2013ERK\u2013c-Jun signaling pathway. NAC supplementation was associated with partial restoration of E-cadherin, reduced MMP-7 expression, and attenuation of ERK\/c-Jun phosphorylation. No systemic toxicity or weight loss was observed, indicating good tolerability of the model. This non-surgical ingestion-based model faithfully recapitulates key epithelial features of LPRD and provides a feasible platform for mechanistic investigation and exploratory therapeutic studies. NAC may exert protective effects against acid-induced epithelial injury in this model.<\/jats:p>","DOI":"10.3390\/cells15020210","type":"journal-article","created":{"date-parts":[[2026,1,23]],"date-time":"2026-01-23T13:55:34Z","timestamp":1769176534000},"page":"210","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Establishing a Non-Surgical Mouse Model of Laryngopharyngeal Reflux Disease: Acid-Induced Epithelial Disruption and Protective Role of N-Acetylcysteine"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-2739-4104","authenticated-orcid":false,"given":"You Yeon","family":"Chung","sequence":"first","affiliation":[{"name":"Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Korea University, Seoul 02842, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7186-4290","authenticated-orcid":false,"given":"Byoungjae","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Korea University, Seoul 02842, Republic of Korea"},{"name":"Neuroscience Research Institute, College of Medicine, Korea University, Seoul 02842, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Juhyun","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Korea University, Seoul 02842, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sooun","family":"Kwak","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Korea University, Seoul 02842, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mingeun","family":"Jung","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Korea University, Seoul 02842, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7862-1662","authenticated-orcid":false,"given":"Yeon Soo","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Korea University, Seoul 02842, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Seung-Kuk","family":"Baek","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Korea University, Seoul 02842, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2743","DOI":"10.1007\/s00405-021-07201-w","article-title":"Effects of acids, pepsin, bile acids, and trypsin on laryngopharyngeal reflux diseases: Physiopathology and therapeutic targets","volume":"279","author":"Li","year":"2022","journal-title":"Eur. Arch. Otorhinolaryngol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"164","DOI":"10.1136\/gut.2009.194191","article-title":"Acid and weakly acidic solutions impair mucosal integrity of distal exposed and proximal non-exposed human oesophagus","volume":"59","author":"Farre","year":"2010","journal-title":"Gut"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1174","DOI":"10.1002\/lary.27591","article-title":"Clinical outcomes of laryngopharyngeal reflux treatment: A systematic review and meta-analysis","volume":"129","author":"Lechien","year":"2019","journal-title":"Laryngoscope"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1","DOI":"10.3310\/hta25030","article-title":"Lansoprazole for persistent throat symptoms in secondary care: The TOPPITS RCT","volume":"25","author":"Wilson","year":"2021","journal-title":"Health Technol. Assess."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1136\/gutjnl-2021-325097","article-title":"Proton pump inhibitors and risk of gastric cancer: Population-based cohort study","volume":"71","author":"Abrahami","year":"2022","journal-title":"Gut"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Brusselaers, N., Wahlin, K., Engstrand, L., and Lagergren, J. (2017). Maintenance therapy with proton pump inhibitors and risk of gastric cancer: A nationwide population-based cohort study in Sweden. BMJ Open, 7.","DOI":"10.1136\/bmjopen-2017-017739"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1136\/gutjnl-2017-314605","article-title":"Long-term proton pump inhibitors and risk of gastric cancer development after treatment for Helicobacter pylori: A population-based study","volume":"67","author":"Cheung","year":"2018","journal-title":"Gut"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"913","DOI":"10.1177\/000348940511401204","article-title":"Laryngeal epithelial defenses against laryngopharyngeal reflux: Investigations of E-cadherin, carbonic anhydrase isoenzyme III, and pepsin","volume":"114","author":"Gill","year":"2005","journal-title":"Ann. Otol. Rhinol. Laryngol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"937","DOI":"10.1007\/s00405-007-0568-6","article-title":"E-cadherin but not beta-catenin expression is decreased in laryngeal biopsies from patients with laryngopharyngeal reflux","volume":"265","author":"Reichel","year":"2008","journal-title":"Eur. Arch. Otorhinolaryngol."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Im, N.R., Lee, D.Y., Kim, B., Kim, J., Jung, K.Y., Kim, T.H., and Baek, S.K. (2019). Role of Matrix Metalloproteinases 7 in the Pathogenesis of Laryngopharyngeal Reflux: Decreased E-cadherin in Acid exposed Primary Human Pharyngeal Epithelial Cells. Int. J. Mol. Sci., 20.","DOI":"10.3390\/ijms20215276"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1007\/s00109-021-02166-z","article-title":"Matrix metalloproteinase-7 induces E-cadherin cleavage in acid-exposed primary human pharyngeal epithelial cells via the ROS\/ERK\/c-Jun pathway","volume":"100","author":"Im","year":"2022","journal-title":"J. Mol. Med."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Lynch, C.C., Vargo-Gogola, T., Matrisian, L.M., and Fingleton, B. (2010). Cleavage of E-Cadherin by Matrix Metalloproteinase-7 Promotes Cellular Proliferation in Nontransformed Cell Lines via Activation of RhoA. J. Oncol., 2010.","DOI":"10.1155\/2010\/530745"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1831","DOI":"10.1016\/S0002-9440(10)64318-0","article-title":"Matrilysin (matrix metalloproteinase-7) mediates E-cadherin ectodomain shedding in injured lung epithelium","volume":"162","author":"McGuire","year":"2003","journal-title":"Am. J. Pathol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"13","DOI":"10.3164\/jcbn.40.13","article-title":"Inflammation and oxidative stress in gastroesophageal reflux disease","volume":"40","author":"Yoshida","year":"2007","journal-title":"J. Clin. Biochem. Nutr."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"G411","DOI":"10.1152\/ajpgi.00373.2007","article-title":"Mechanisms of oxidant production in esophageal squamous cell and Barrett\u2019s cell lines","volume":"294","author":"Feagins","year":"2008","journal-title":"Am. J. Physiol. Gastrointest. Liver Physiol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"2035","DOI":"10.1093\/carcin\/bgs241","article-title":"Inducible nitric oxide synthase (iNOS) and nitric oxide (NO) are important mediators of reflux-induced cell signalling in esophageal cells","volume":"33","author":"McAdam","year":"2012","journal-title":"Carcinogenesis"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1801","DOI":"10.1093\/carcin\/20.9.1801","article-title":"An esophagogastroduodenal anastomosis model for esophageal adenocarcinogenesis in rats and enhancement by iron overload","volume":"20","author":"Chen","year":"1999","journal-title":"Carcinogenesis"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"753","DOI":"10.1038\/labinvest.3700079","article-title":"Phenotype of columnar-lined esophagus in rats with esophagogastroduodenal anastomosis: Similarity to human Barrett\u2019s esophagus","volume":"84","author":"Su","year":"2004","journal-title":"Lab. Investig."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"328","DOI":"10.1152\/japplphysiol.00064.2006","article-title":"Neural and hydroxyl radical mechanisms underlying laryngeal airway hyperreactivity induced by laryngeal acid-pepsin insult in anesthetized rats","volume":"101","author":"Tsai","year":"2006","journal-title":"J. Appl. Physiol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1584","DOI":"10.1152\/japplphysiol.91517.2008","article-title":"Role of ATP in the ROS-mediated laryngeal airway hyperreactivity induced by laryngeal acid-pepsin insult in anesthetized rats","volume":"106","author":"Tsai","year":"2009","journal-title":"J. Appl. Physiol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1208","DOI":"10.1136\/jim-2020-001691","article-title":"Non-surgical animal model of gastroesophageal reflux disease by overeating induced in mice","volume":"69","author":"Im","year":"2021","journal-title":"J. Investig. Med."},{"key":"ref_22","first-page":"757","article-title":"The effect of N-acetyl cysteine on laryngopharyngeal reflux","volume":"51","author":"Dabirmoghaddam","year":"2013","journal-title":"Acta Med. Iran."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"299","DOI":"10.1053\/gast.2002.30993","article-title":"Acid exposure activates the mitogen-activated protein kinase pathways in Barrett\u2019s esophagus","volume":"122","author":"Souza","year":"2002","journal-title":"Gastroenterology"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"2445","DOI":"10.3748\/wjg.v12.i15.2445","article-title":"Influence of acid and bile acid on ERK activity, PPARgamma expression and cell proliferation in normal human esophageal epithelial cells","volume":"12","author":"Jiang","year":"2006","journal-title":"World J. Gastroenterol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1042","DOI":"10.1136\/gutjnl-2013-305533","article-title":"In oesophageal squamous cells exposed to acidic bile salt medium, omeprazole inhibits IL-8 expression through effects on nuclear factor-kappaB and activator protein-1","volume":"63","author":"Huo","year":"2014","journal-title":"Gut"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Im, N.R., Kim, B., Jung, K.Y., and Baek, S.K. (2021). Usefulness of matrix metalloproteinase-7 in saliva as a diagnostic biomarker for laryngopharyngeal reflux disease. Sci. Rep., 11.","DOI":"10.1038\/s41598-021-96554-7"}],"container-title":["Cells"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4409\/15\/2\/210\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,23]],"date-time":"2026-01-23T14:01:41Z","timestamp":1769176901000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4409\/15\/2\/210"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,22]]},"references-count":26,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,1]]}},"alternative-id":["cells15020210"],"URL":"https:\/\/doi.org\/10.3390\/cells15020210","relation":{},"ISSN":["2073-4409"],"issn-type":[{"value":"2073-4409","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,22]]}}}