{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,15]],"date-time":"2026-08-15T17:32:11Z","timestamp":1786815131837,"version":"build-2736575974"},"reference-count":33,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2022,5,31]],"date-time":"2022-05-31T00:00:00Z","timestamp":1653955200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"American University of Sharjah (RS) and University of Sharjah (NAK)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Naegleria\u00a0fowleri and Balamuthia mandrillaris are pathogenic free-living amoebae that infect the central nervous system with over 95% mortality rates. Although several compounds have shown promise in vitro but associated side effects and\/or prolonged approval processes for clinical applications have led to limited success. To overcome this, drug repurposing of marketed compounds with known mechanism of action is considered a viable approach that has potential to expedite discovery and application of anti-amoebic compounds. In fact, many of the drugs currently employed in the treatment of N. fowleri and B. mandrillaris, such as amphotericin B, fluconazole, rifampin and miltefosine, are repurposed drugs. Here, we evaluated a range of clinical and laboratory compounds including metformin, quinclorac, indaziflam, inositol, nateglinide, 2,6-DNBT, trans-cinnamic acid, terbuthylazine, acarbose, glimepiride, vildagliptin, cellulase, thaxtomin A, repaglinide and dimethyl peptidase (IV) inhibitor against N. fowleri and B. mandrillaris. Anti-amoebic assays revealed that indaziflam, nateglinide, 2,6-DNBT, terbuthylazine, acarbose and glimepiride exhibited potent amoebicidal properties against both N. fowleri and B. mandrillaris. Notably, all compounds tested showed minimal human (HaCaT) cell cytotoxicity as determined by lactate dehydrogenase release. Prospective research using animal models is warranted to determine the potential of these repurposed compounds, as well as the need for investigating the intranasal route of delivery to treat these devastating infections.<\/jats:p>","DOI":"10.3390\/antibiotics11060749","type":"journal-article","created":{"date-parts":[[2022,5,31]],"date-time":"2022-05-31T09:24:29Z","timestamp":1653989069000},"page":"749","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Antiamoebic Properties of Laboratory and Clinically Used Drugs against Naegleria\u00a0fowleri and Balamuthia mandrillaris"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9646-6208","authenticated-orcid":false,"given":"Ruqaiyyah","family":"Siddiqui","sequence":"first","affiliation":[{"name":"College of Arts and Sciences, American University of Sharjah, Sharjah 26666, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammad Ridwane","family":"Mungroo","sequence":"additional","affiliation":[{"name":"College of Arts and Sciences, American University of Sharjah, Sharjah 26666, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tengku Shahrul","family":"Anuar","sequence":"additional","affiliation":[{"name":"Centre for Medical Laboratory Technology, Faculty of Health Sciences, Puncak Alam Campus, Universiti Teknologi MARA, Shah Alam 40450, Selangor, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ahmad M.","family":"Alharbi","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Taif University, Taif 21944, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hasan","family":"Alfahemi","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology, Faculty of Medicine, Al-Baha University, Al-Baha 65799, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adel B.","family":"Elmoselhi","sequence":"additional","affiliation":[{"name":"Department of Basic Medical Sciences, College of Medicine, University of Sharjah, Sharjah 27272, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7667-8553","authenticated-orcid":false,"given":"Naveed Ahmed","family":"Khan","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah 27272, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,31]]},"reference":[{"key":"ref_1","unstructured":"Martinez, A.J. 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