{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,10]],"date-time":"2026-08-10T01:34:09Z","timestamp":1786325649083,"version":"build-2736575974"},"reference-count":40,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2019,2,12]],"date-time":"2019-02-12T00:00:00Z","timestamp":1549929600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003664","name":"Korea Forest Service","doi-asserted-by":"publisher","award":["2017035A00-1819-BA01"],"award-info":[{"award-number":["2017035A00-1819-BA01"]}],"id":[{"id":"10.13039\/501100003664","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003718","name":"Korea Institute of Oriental Medicine","doi-asserted-by":"publisher","award":["KSN1812080"],"award-info":[{"award-number":["KSN1812080"]}],"id":[{"id":"10.13039\/501100003718","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Exposure to particulate matter is a risk factor for various ocular surface diseases, including keratoconjunctivitis sicca (KCS). In this study, we investigated the protective effects of apricot kernel extract (AKE) and its bioactive compound, amygdalin, on KCS induced by exposure to urban particulate matter (UPM). In the in vivo experiments, eye drops containing 0.5 mg\/mL AKE (AKE-0.5) or 1 mg\/mL AKE (AKE-1) were administered directly into the eyes of female rats after UPM exposure. Additionally, the effect of AKE and amygdalin on matrix metalloproteinases (MMPs) activity and the expressions of inflammatory factors, including tumor necrosis factor (TNF)-\u03b1 and interleukin (IL)-6, was investigated in conjunctival epithelial cells in vitro. Topical administration of AKE-1 attenuated UPM exposure-induced reduction of tear secretion. Both AKE-0.5 and AKE-1 inhibited UPM exposure-induced corneal epithelial damage and irregularity. AKE also protected against UPM exposure-induced disruption of the mucin-4 layer on the ocular surface. In addition, AKE and amygdalin prevented UPM-induced activation of MMPs and upregulation of TNF-\u03b1 and IL-6 in conjunctival epithelial cells. Therefore, AKE may have protective effects against UPM exposure-induced KCS via the inhibition of MMPs and inflammation. The pharmacological activities of AKE may be in part due to its bioactive compound, amygdalin.<\/jats:p>","DOI":"10.3390\/molecules24030650","type":"journal-article","created":{"date-parts":[[2019,2,13]],"date-time":"2019-02-13T02:49:44Z","timestamp":1550026184000},"page":"650","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Apricot Kernel Extract and Amygdalin Inhibit Urban Particulate Matter-Induced Keratoconjunctivitis Sicca"],"prefix":"10.3390","volume":"24","author":[{"given":"Soo-Wang","family":"Hyun","sequence":"first","affiliation":[{"name":"Herbal Medicine Research Division, Korea Institute of Oriental Medicine, Daejeon 34054, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9003-2158","authenticated-orcid":false,"given":"Junghyun","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Oral Pathology, School of Dentistry, Chonbuk National University, Jeonju 54896, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bongkyun","family":"Park","sequence":"additional","affiliation":[{"name":"Clinical Medicine Division, Korea Institute of Oriental Medicine, Daejeon 34054, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kyuhyung","family":"Jo","sequence":"additional","affiliation":[{"name":"Clinical Medicine Division, Korea Institute of Oriental Medicine, Daejeon 34054, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tae Gu","family":"Lee","sequence":"additional","affiliation":[{"name":"Clinical Medicine Division, Korea Institute of Oriental Medicine, Daejeon 34054, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jin Sook","family":"Kim","sequence":"additional","affiliation":[{"name":"Herbal Medicine Research Division, Korea Institute of Oriental Medicine, Daejeon 34054, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7610-9887","authenticated-orcid":false,"given":"Chan-Sik","family":"Kim","sequence":"additional","affiliation":[{"name":"Clinical Medicine Division, Korea Institute of Oriental Medicine, Daejeon 34054, Korea"},{"name":"Korean Medicine Life Science, University of Science and Technology (UST), Daejeon 34054, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1016\/S1542-0124(12)70081-2","article-title":"The definition and classification of dry eye disease: Report of the definition and classification subcommittee of the international dry eye workshop (2007)","volume":"5","author":"Michael","year":"2007","journal-title":"Ocul. 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