{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T14:28:20Z","timestamp":1779373700057,"version":"3.53.1"},"reference-count":39,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T00:00:00Z","timestamp":1774483200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China\n\t\t\t\t\t\t\t\t\t              https:\/\/ror.org\/01h0zpd94","doi-asserted-by":"publisher","award":["32501130"],"award-info":[{"award-number":["32501130"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Open Fund of the Guangdong Provincial Key Laboratory of Utilization and Conservation of Food and Medicinal Resources in Northern Region","award":["FMR2023001Z"],"award-info":[{"award-number":["FMR2023001Z"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Natural anthraquinones possess a wide range of biological activities, including antibacterial, antiviral, antitumor, and antioxidant effects. However, studies on their ability to inhibit amyloid protein aggregation remain relatively limited. In this study, we used insulin as a model protein to investigate the anti-amyloidogenic potential of several natural anthraquinones. Specifically, the inhibitory mechanisms of five anthraquinones (emodin, anthraflavin, aloe-emodin, alizarin, and purpurin) on insulin amyloid fibrillation were explored in both dilute and crowded environments (PEG 2000 and PEG 4000). Multidisciplinary analytical results demonstrated that all five anthraquinones could effectively inhibit insulin amyloid fibrillation in both dilute and crowded environments. Simultaneously, crowded agents themselves also exhibited inhibitory effects on insulin amyloid aggregation. However, the inhibitory efficacy of anthraquinones was weaker in crowded environments than in dilute solutions, indicating that although crowded agents themselves suppressed insulin aggregation, they may interfere with the regulatory roles of anthraquinones on insulin aggregation behavior. Interestingly, purpurin showed stronger inhibitory activity in crowded environments compared to dilute solutions. Furthermore, fluorescence spectral analysis suggested that the quenching mechanism of insulin by all these anthraquinones was identified as static quenching mode. Molecular simulation studies revealed that anthraquinones could bind to the aggregation-prone regions of insulin via hydrogen bonding and hydrophobic interactions, thereby inhibiting insulin amyloid aggregation. Notably, the inhibitory capacity of these compounds was correlated with their structural features and the binding affinities to insulin. Collectively, this study explored the anti-amyloid activity of anthraquinones, which held significant research value for the development of potential therapeutic agents for amyloid-associated proteinopathies.<\/jats:p>","DOI":"10.3390\/molecules31071092","type":"journal-article","created":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T15:10:24Z","timestamp":1774537824000},"page":"1092","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Anthraquinones Inhibit Insulin Amyloidosis in Crowded Environments"],"prefix":"10.3390","volume":"31","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4104-6657","authenticated-orcid":false,"given":"Jiaxing","family":"Zhang","sequence":"first","affiliation":[{"name":"Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China"},{"name":"State Key Laboratory of Chemical Engineering and Low-Carbon Technology, Tianjin University, Tianjin 300072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wen","family":"Wang","sequence":"additional","affiliation":[{"name":"Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zubiyan","family":"Yibula","sequence":"additional","affiliation":[{"name":"School of Life Sciences, Faculty of Medicine, Tianjin University, Tianjin 300072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1654-2130","authenticated-orcid":false,"given":"Xin","family":"Peng","sequence":"additional","affiliation":[{"name":"School of Life Sciences, Faculty of Medicine, Tianjin University, Tianjin 300072, China"},{"name":"Guangdong Provincial Key Laboratory of Utilization and Conservation of Food and Medicinal Resources in Northern Region, Shaoguan University, Shaoguan 512005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rongxin","family":"Su","sequence":"additional","affiliation":[{"name":"Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China"},{"name":"Collaborative Innovation Centre of Chemical Science and Engineering (Tianjin), Tianjin 300072, China"},{"name":"Tianjin Key Laboratory of Membrane Science and Desalination Technology, Tianjin University, Tianjin 300072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7378-1392","authenticated-orcid":false,"given":"Wei","family":"Qi","sequence":"additional","affiliation":[{"name":"Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China"},{"name":"State Key Laboratory of Chemical Engineering and Low-Carbon Technology, Tianjin University, Tianjin 300072, China"},{"name":"Collaborative Innovation Centre of Chemical Science and Engineering (Tianjin), Tianjin 300072, China"},{"name":"Tianjin Key Laboratory of Membrane Science and Desalination Technology, Tianjin University, Tianjin 300072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Rosetti, B., and Marchesan, S. 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