{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T22:17:00Z","timestamp":1790806620143,"version":"4.1.0"},"reference-count":46,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2024,8,16]],"date-time":"2024-08-16T00:00:00Z","timestamp":1723766400000},"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>Amyloid \u03b2 peptide (A\u03b2) aggregation and deposition are considered the main causes of Alzheimer\u2019s disease. In a previous study, we demonstrated that anionic Zn-phthalocyanine (ZnPc) can interact with the A\u03b2 peptide and inhibit the fibril-formation process. However, due to the inability of anionic ZnPc to cross the intact blood\u2013brain barrier, we decided to explore the interaction of cationic methylated Zn-phthalocyanine (cZnPc) with the peptide. Using a ThT fluorescence assay, we observed that cZnPc dose-dependently and time-dependently inhibited A\u03b21-42 fibril levels under in vitro fibril-formation conditions. Electron microscopy revealed that it caused A\u03b21-42 peptides to form small aggregates. Western blotting and dot immunoblot oligomer experiments demonstrated that cZnPc increased rather than decreased the levels of oligomers from the very early stages of incubation. A binding assay confirmed that cZnPc could bind with the peptide. Docking simulations indicated that the oligomer species of A\u03b21-42 had a higher ability to interact with cZnPc. ANS fluorescence assay results indicated that cZnPc did not affect the hydrophobicity of the peptide. However, cZnPc significantly increased intrinsic tyrosine fluorescence of the peptide after 8 h of incubation in fibril-formation conditions. Importantly, cell culture experiments demonstrated that cZnPc did not exhibit any toxicity up to a concentration of 10 \u00b5M. Instead, it protected a neuronal cell line from A\u03b21-42-induced toxicity. Thus, our results suggest that cZnPc can affect the aggregation process of A\u03b21-42, rendering it non-toxic, which could be crucial for the therapy of Alzheimer\u2019s disease.<\/jats:p>","DOI":"10.3390\/ijms25168931","type":"journal-article","created":{"date-parts":[[2024,8,16]],"date-time":"2024-08-16T06:23:20Z","timestamp":1723789400000},"page":"8931","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["A Cationic Zn-Phthalocyanine Turns Alzheimer\u2019s Amyloid \u03b2 Aggregates into Non-Toxic Oligomers and Inhibits Neurotoxicity in Culture"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1221-7787","authenticated-orcid":false,"given":"Abdullah Md.","family":"Sheikh","sequence":"first","affiliation":[{"name":"Department of Laboratory Medicine, Shimane University Faculty of Medicine, 89-1 Enya Cho, Izumo 693-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shatera","family":"Tabassum","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Shimane University Faculty of Medicine, 89-1 Enya Cho, Izumo 693-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9210-2949","authenticated-orcid":false,"given":"Shozo","family":"Yano","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Shimane University Faculty of Medicine, 89-1 Enya Cho, Izumo 693-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fatema Binte","family":"Abdullah","sequence":"additional","affiliation":[{"name":"Department of Neurology, Shimane University Faculty of Medicine, 89-1 Enya Cho, Izumo 693-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruochen","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Neurology, Shimane University Faculty of Medicine, 89-1 Enya Cho, Izumo 693-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takahisa","family":"Ikeue","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9280-8044","authenticated-orcid":false,"given":"Atsushi","family":"Nagai","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Shimane University Faculty of Medicine, 89-1 Enya Cho, Izumo 693-8501, Japan"},{"name":"Department of Neurology, Shimane University Faculty of Medicine, 89-1 Enya Cho, Izumo 693-8501, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,16]]},"reference":[{"key":"ref_1","unstructured":"Rowland, L.P., Pedley, T.A., and Merritt, H.H. 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