{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T05:01:41Z","timestamp":1787029301102,"version":"build-2736575974"},"reference-count":19,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,4,16]],"date-time":"2025-04-16T00:00:00Z","timestamp":1744761600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Korea Health Industry Development Institute (KHIDI)","award":["RS-2023-KH135936"],"award-info":[{"award-number":["RS-2023-KH135936"]}]},{"name":"Korea Health Industry Development Institute (KHIDI)","award":["SMO1250321"],"award-info":[{"award-number":["SMO1250321"]}]},{"DOI":"10.13039\/501100003710","name":"Ministry of Health and Welfare, Republic of Korea","doi-asserted-by":"publisher","award":["RS-2023-KH135936"],"award-info":[{"award-number":["RS-2023-KH135936"]}],"id":[{"id":"10.13039\/501100003710","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003710","name":"Ministry of Health and Welfare, Republic of Korea","doi-asserted-by":"publisher","award":["SMO1250321"],"award-info":[{"award-number":["SMO1250321"]}],"id":[{"id":"10.13039\/501100003710","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Samsung Medical Center","award":["RS-2023-KH135936"],"award-info":[{"award-number":["RS-2023-KH135936"]}]},{"name":"Samsung Medical Center","award":["SMO1250321"],"award-info":[{"award-number":["SMO1250321"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceutics"],"abstract":"<jats:p>Objective: To investigate the toxicity of cetalkonium chloride (CKC) on primary cultured human corneal epithelial cells (HCECs). Methods: HCECs were subjected to various concentrations (0.03125 \u00d7 10\u22124 to 2.0 \u00d7 10\u22124% (w\/v)) of CKC for durations ranging from 24 to 72 h. Cell viability was evaluated using the CCK-8 kit along with live and dead cell staining. Intracellular reactive oxygen species (ROS) levels were measured 20 min following CKC exposure. Observations of changes in cell morphology, cytoplasmic actin filaments, and mitochondrial distribution were conducted using immunocytochemistry and MitoTracker assays. Protein expression levels related to cell survival pathways, including mTOR, ERK, Akt, Bcl-xL, and BAX, were examined via Western blot analysis. Results: CKC exhibited dose-dependent toxicity in HCECs. Exposure to CKC concentrations below 0.125 \u00d7 10\u22124% resulted in no significant decrease in HCEC viability for up to 72 h. Conversely, exposure to CKC at concentrations of 1.0 \u00d7 10\u22124% or higher led to significantly decreased HCEC viability. Following exposure to higher concentrations of CKC, elevated levels of intracellular ROS and LDH release were observed. This toxicity was further characterized by decreased levels of phosphorylated mTOR, phosphorylated Akt, phosphorylated ERK, and Bcl-xL, as well as an increase in BAX expression. As the CKC concentration increased, HCECs decreased in size, and mitochondria displayed a loss of characteristic punctate staining. Conclusions: Our findings indicated that exposure to CKC caused significant toxicity in HCECs, which varied with concentration and duration of exposure. This toxicity was associated with an increase in ROS, mitochondrial alterations, and a decline in activity of the cell survival pathways.<\/jats:p>","DOI":"10.3390\/pharmaceutics17040522","type":"journal-article","created":{"date-parts":[[2025,4,16]],"date-time":"2025-04-16T06:12:06Z","timestamp":1744783926000},"page":"522","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["In Vitro Toxicity of Cetalkonium Chloride on Corneal Epithelial Cells"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8662-6279","authenticated-orcid":false,"given":"Joo-Hee","family":"Park","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, Dongguk University Ilsan Hospital, Goyang 10326, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Choul Yong","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Suwon 06351, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"312","DOI":"10.1016\/j.preteyeres.2010.03.001","article-title":"Preservatives in eyedrops: The good, the bad and the ugly","volume":"29","author":"Baudouin","year":"2010","journal-title":"Prog. 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