{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T02:37:15Z","timestamp":1780454235647,"version":"3.54.1"},"reference-count":34,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2024,4,27]],"date-time":"2024-04-27T00:00:00Z","timestamp":1714176000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"IOF","award":["F2020\/IOF-StarTT\/034"],"award-info":[{"award-number":["F2020\/IOF-StarTT\/034"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Age-related macular degeneration (AMD) is an age-related disorder that is a global public health problem. The non-enzymatic Maillard reaction results in the formation of advanced glycation end products (AGEs). Accumulation of AGEs in drusen plays a key role in AMD. AGE-reducing drugs may contribute to the prevention and treatment of AGE-related disease. Fructosamine oxidase (FAOD) acts on fructosyl lysine and fructosyl valine. Based upon the published results of fructosamine 3-kinase (FN3K) and FAOD obtained in cataract and presbyopia, we studied ex vivo FAOD treatment as a non-invasive AMD therapy. On glycolaldehyde-treated porcine retinas, FAOD significantly reduced AGE autofluorescence (p = 0.001). FAOD treatment results in a breakdown of AGEs, as evidenced using UV fluorescence, near-infrared microspectroscopy on stained tissue sections of human retina, and gel permeation chromatography. Drusen are accumulations of AGEs that build up between Bruch\u2019s membrane and the retinal pigment epithelium. On microscopy slides of human retina affected by AMD, a significant reduction in drusen surface to 45 \u00b1 21% was observed following FAOD treatment. Enzymatic digestion followed by mass spectrometry of fructose- and glucose-based AGEs (produced in vitro) revealed a broader spectrum of substrates for FAOD, as compared to FN3K, including the following: fructosyllysine, carboxymethyllysine, carboxyethyllysine, and imidazolone. In contrast to FN3K digestion, agmatine (4-aminobutyl-guanidine) was formed following FAOD treatment in vitro. The present study highlights the therapeutic potential of FAOD in AMD by repairing glycation-induced damage.<\/jats:p>","DOI":"10.3390\/ijms25094779","type":"journal-article","created":{"date-parts":[[2024,5,3]],"date-time":"2024-05-03T08:02:22Z","timestamp":1714723342000},"page":"4779","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Fructosyl Amino Oxidase as a Therapeutic Enzyme in Age-Related Macular Degeneration"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5702-6792","authenticated-orcid":false,"given":"Joris R.","family":"Delanghe","sequence":"first","affiliation":[{"name":"Department of Diagnostic Sciences, Ghent University, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7733-2941","authenticated-orcid":false,"given":"Jose","family":"Diana Di Mavungu","sequence":"additional","affiliation":[{"name":"Department of Green Chemistry and Technology, MSsmall Expertise Centre, Mass Spectrometry Analysis of Small Organic Molecules, Ghent University, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6608-0443","authenticated-orcid":false,"given":"Koen","family":"Beerens","sequence":"additional","affiliation":[{"name":"Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonas","family":"Himpe","sequence":"additional","affiliation":[{"name":"Department of Diagnostic Sciences, Ghent University, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nezahat","family":"Bostan","sequence":"additional","affiliation":[{"name":"Antwerp Biobank, Antwerp University Hospital, 2650 Antwerp, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9183-4390","authenticated-orcid":false,"given":"Marijn M.","family":"Speeckaert","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine and Pediatrics, Ghent University, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4861-9630","authenticated-orcid":false,"given":"Henk","family":"Vrielinck","sequence":"additional","affiliation":[{"name":"Department of Solid State Sciences, Ghent University, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anne","family":"Vral","sequence":"additional","affiliation":[{"name":"Department of Human Structure and Repair, Ghent University, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Caroline","family":"Van Den Broeke","sequence":"additional","affiliation":[{"name":"Department of Pathology, Ghent University Hospital, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5331-9486","authenticated-orcid":false,"given":"Manon","family":"Huizing","sequence":"additional","affiliation":[{"name":"Antwerp Biobank, Antwerp University Hospital, 2650 Antwerp, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2418-701X","authenticated-orcid":false,"given":"Elisabeth","family":"Van Aken","sequence":"additional","affiliation":[{"name":"Department of Head and Skin, Ghent University, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e106","DOI":"10.1016\/S2214-109X(13)70145-1","article-title":"Global prevalence of age-related macular degeneration and disease burden projection for 2020 and 2040: A systematic review and meta-analysis","volume":"2","author":"Wong","year":"2014","journal-title":"Lancet Glob. 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