{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,31]],"date-time":"2026-03-31T03:49:43Z","timestamp":1774928983803,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T00:00:00Z","timestamp":1768435200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012544","name":"China Medical University, Taiwan","doi-asserted-by":"crossref","award":["CMU114-S-15"],"award-info":[{"award-number":["CMU114-S-15"]}],"id":[{"id":"10.13039\/501100012544","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100005007","name":"Asia University, Taiwan","doi-asserted-by":"publisher","award":["ASIA-111-CMUH-01"],"award-info":[{"award-number":["ASIA-111-CMUH-01"]}],"id":[{"id":"10.13039\/501100005007","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The emergence of SARS-CoV-2, the etiological agent of COVID-19, has resulted in widespread global infection and millions of deaths. Viral entry is initiated by the interaction between the viral spike (S) protein and the host cell receptor ACE2, followed by TMPRSS2-mediated proteolytic activation that facilitates membrane fusion. Bitter melon (Momordica charantia L., MC), a traditional medicinal and edible plant widely used in tropical Asia, possesses notable anti-inflammatory, antioxidant, antitumor, and hypoglycemic properties. In this study, the ethanol extract of bitter melon (EMC) markedly downregulated ACE2 and TMPRSS2 expression in both in vitro and in vivo models without inducing cytotoxicity. Furthermore, phytochemicals isolated from EMC\u2014including p-coumaric acid, rutin, and quercetin\u2014exhibited comparable inhibitory effects. These results indicate that EMC and its bioactive constituents may interfere with SARS-CoV-2 entry by modulating the ACE2\/TMPRSS2 axis, highlighting their potential as natural adjuncts for COVID-19 prevention or management.<\/jats:p>","DOI":"10.3390\/ijms27020868","type":"journal-article","created":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T12:31:41Z","timestamp":1768480301000},"page":"868","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Bioactive Compounds of Momordica charantia L. Downregulate the Protein Expression of ACE2 and TMPRSS2 In Vivo and In Vitro"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1819-7046","authenticated-orcid":false,"given":"Che-Yi","family":"Chao","sequence":"first","affiliation":[{"name":"Department of Food Nutrition and Health Biotechnology, Asia University, Taichung 413, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Woei-Cheang","family":"Shyu","sequence":"additional","affiliation":[{"name":"Translational Medicine Research Center, China Medical University Hospital, Taichung 413, Taiwan"},{"name":"Graduate Institute of Biomedical Sciences, China Medical University, Taichung 413, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0649-4243","authenticated-orcid":false,"given":"Chih-Lung","family":"Lin","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Asia University Hospital, Taichung 413, Taiwan"},{"name":"Department of Occupational Therapy, Asia University, Taichung 413, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9387-680X","authenticated-orcid":false,"given":"Wen-Ping","family":"Jiang","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, China Medical University, Taichung 404, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Atsushi","family":"Inose","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Nihon Pharmaceutical University, Saitama 362-0806, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Song-Jie","family":"Chiang","sequence":"additional","affiliation":[{"name":"Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, College of Chinese Medicine, China Medical University, Taichung 404, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wen-Liang","family":"Wu","sequence":"additional","affiliation":[{"name":"School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung 404, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3642-8047","authenticated-orcid":false,"given":"Jaung-Geng","family":"Lin","sequence":"additional","affiliation":[{"name":"School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung 404, Taiwan"},{"name":"Chinese Medicine Research Center, China Medical University, Taichung 404, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9822-3485","authenticated-orcid":false,"given":"Guan-Jhong","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Food Nutrition and Health Biotechnology, Asia University, Taichung 413, Taiwan"},{"name":"Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, College of Chinese Medicine, China Medical University, Taichung 404, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,15]]},"reference":[{"key":"ref_1","unstructured":"(2025, November 10). 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