{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,12]],"date-time":"2026-06-12T07:20:04Z","timestamp":1781248804651,"version":"3.54.1"},"reference-count":40,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2025,10,18]],"date-time":"2025-10-18T00:00:00Z","timestamp":1760745600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Over the past five decades, the emergence and re-emergence of multiple flaviviruses have triggered significant global outbreaks, posing serious threats to public health. Among them, West Nile virus (WNV) is a major cause of mosquito-borne illness, typically presenting as an acute systemic febrile disease and, in some cases, progressing to the central nervous system involvement. No specific antiviral therapies or effective vaccines are available for WNV infections. In this context, antimicrobial peptides (AMPs) with antiviral properties\u2014known as antiviral peptides (AVPs)\u2014have gained attention as potential therapeutic agents due to their ability to interfere with various stages of the viral life cycle. Two frog-derived melittin-like peptides, AR-23 and RV-23, were synthesized and purified, and their hemolytic activity was assessed on human erythrocytes. Antiviral activity against WNV was evaluated in Vero cells using cytopathic effect reduction assays and real-time PCR quantification of viral RNA. Time-of-addition experiments were conducted to explore the stage of viral inhibition. In silico molecular docking studies were performed to examine interactions between the peptides and the viral E glycoprotein. Both peptides displayed strong antiviral effects during the early phases of infection, likely through direct interaction with viral particles and disruption of virus\u2013host interactions. Compared with melittin, AR-23 and RV-23 showed greater efficacy and lower cytotoxicity, highlighting their potential as promising therapeutic candidates for flavivirus infections.<\/jats:p>","DOI":"10.3390\/ijms262010148","type":"journal-article","created":{"date-parts":[[2025,10,20]],"date-time":"2025-10-20T08:18:54Z","timestamp":1760948334000},"page":"10148","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Structure\u2013Function Insights into Frog Skin Peptides Reveal Potent Inhibition of West Nile Virus Entry"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7991-8700","authenticated-orcid":false,"given":"Carla","family":"Zannella","sequence":"first","affiliation":[{"name":"Department of Experimental Medicine, University of Campania Luigi Vanvitelli, 80138 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1648-4519","authenticated-orcid":false,"given":"Annalisa","family":"Chianese","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, University of Campania Luigi Vanvitelli, 80138 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9923-3194","authenticated-orcid":false,"given":"Rosa","family":"Giugliano","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, University of Campania Luigi Vanvitelli, 80138 Naples, Italy"},{"name":"Department of Veterinary Medicine and Animal Production, University of Naples Federico II, 80137 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0516-5683","authenticated-orcid":false,"given":"Valeria","family":"Stefanizzi","sequence":"additional","affiliation":[{"name":"Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6789-7057","authenticated-orcid":false,"given":"Alessandra","family":"Monti","sequence":"additional","affiliation":[{"name":"Institute of Biostructures and Bioimaging (IBB), National Research Council (CNR), 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2952-6658","authenticated-orcid":false,"given":"Nunzianna","family":"Doti","sequence":"additional","affiliation":[{"name":"Institute of Biostructures and Bioimaging (IBB), National Research Council (CNR), 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emilia","family":"Palazzotto","sequence":"additional","affiliation":[{"name":"Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties \u201cG. D\u2019Alessandro\u201d, University of Palermo, 90127 Palermo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9293-5924","authenticated-orcid":false,"given":"Floriana","family":"Bonura","sequence":"additional","affiliation":[{"name":"Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties \u201cG. D\u2019Alessandro\u201d, University of Palermo, 90127 Palermo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7874-6289","authenticated-orcid":false,"given":"Giovanni M.","family":"Giammanco","sequence":"additional","affiliation":[{"name":"Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties \u201cG. D\u2019Alessandro\u201d, University of Palermo, 90127 Palermo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0338-6450","authenticated-orcid":false,"given":"Antonio","family":"Mastino","sequence":"additional","affiliation":[{"name":"The Institute of Translational Pharmacology (IFT), National Research Council (CNR), 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7748-0880","authenticated-orcid":false,"given":"Simona","family":"De Grazia","sequence":"additional","affiliation":[{"name":"Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties \u201cG. D\u2019Alessandro\u201d, University of Palermo, 90127 Palermo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7898-583X","authenticated-orcid":false,"given":"Francesca","family":"Marino-Merlo","sequence":"additional","affiliation":[{"name":"Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1576-6290","authenticated-orcid":false,"given":"Massimiliano","family":"Galdiero","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, University of Campania Luigi Vanvitelli, 80138 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0395-7962","authenticated-orcid":false,"given":"Anna","family":"De Filippis","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, University of Campania Luigi Vanvitelli, 80138 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"796","DOI":"10.1038\/s41564-020-0714-0","article-title":"The continued threat of emerging flaviviruses","volume":"5","author":"Pierson","year":"2020","journal-title":"Nat. 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