{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T19:16:11Z","timestamp":1785784571443,"version":"3.56.0"},"reference-count":58,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2024,9,7]],"date-time":"2024-09-07T00:00:00Z","timestamp":1725667200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Alkaptonuria (AKU) is a rare autosomal recessive metabolic disorder caused by mutations in the homogentisate 1,2-dioxygenase (HGD) gene, leading to the accumulation of homogentisic acid (HGA), causing severe inflammatory conditions. Recently, the presence of serum amyloid A (SAA) has been reported in AKU tissues, classifying AKU as novel secondary amyloidosis; AA amyloidosis is characterized by the extracellular tissue deposition of fibrils composed of fragments of SAA. AA amyloidosis may complicate several chronic inflammatory conditions, like rheumatoid arthritis, ankylosing spondylitis, inflammatory bowel disease, chronic infections, neoplasms, etc. Treatments of AA amyloidosis relieve inflammatory disorders by reducing SAA concentrations; however, no definitive therapy is currently available. SAA regulation is a crucial step to improve AA secondary amyloidosis treatments. Here, applying a comprehensive in vitro and in silico approach, we provided evidence that HGA is a disruptor modulator of SAA, able to enhance its polymerization, fibril formation, and aggregation upon SAA\/SAP colocalization. In silico studies deeply dissected the SAA misfolding molecular pathway and SAA\/HGA binding, suggesting novel molecular insights about it. Our results could represent an important starting point for identifying novel therapeutic strategies in AKU and AA secondary amyloidosis-related diseases.<\/jats:p>","DOI":"10.3390\/cells13171501","type":"journal-article","created":{"date-parts":[[2024,9,9]],"date-time":"2024-09-09T03:04:18Z","timestamp":1725851058000},"page":"1501","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["HGA Triggers SAA Aggregation and Accelerates Fibril Formation in the C20\/A4 Alkaptonuria Cell Model"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-5369-3950","authenticated-orcid":false,"given":"Pierfrancesco","family":"Mastroeni","sequence":"first","affiliation":[{"name":"ONE-HEALTH Lab, Department of Biotechnology, Chemistry and Pharmacy, University of Siena Via Aldo Moro, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alfonso","family":"Trezza","sequence":"additional","affiliation":[{"name":"ONE-HEALTH Lab, Department of Biotechnology, Chemistry and Pharmacy, University of Siena Via Aldo Moro, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6910-0056","authenticated-orcid":false,"given":"Michela","family":"Geminiani","sequence":"additional","affiliation":[{"name":"ONE-HEALTH Lab, Department of Biotechnology, Chemistry and Pharmacy, University of Siena Via Aldo Moro, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4031-3066","authenticated-orcid":false,"given":"Luisa","family":"Frusciante","sequence":"additional","affiliation":[{"name":"ONE-HEALTH Lab, Department of Biotechnology, Chemistry and Pharmacy, University of Siena Via Aldo Moro, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9281-034X","authenticated-orcid":false,"given":"Anna","family":"Visibelli","sequence":"additional","affiliation":[{"name":"ONE-HEALTH Lab, Department of Biotechnology, Chemistry and Pharmacy, University of Siena Via Aldo Moro, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6976-9086","authenticated-orcid":false,"given":"Annalisa","family":"Santucci","sequence":"additional","affiliation":[{"name":"ONE-HEALTH Lab, Department of Biotechnology, Chemistry and Pharmacy, University of Siena Via Aldo Moro, 53100 Siena, Italy"},{"name":"MetabERN, Department of Biotechnology, Chemistry and Pharmacy, University of Siena Via Aldo Moro, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1038\/s41572-024-00498-x","article-title":"Alkaptonuria","volume":"10","author":"Bernardini","year":"2024","journal-title":"Nat. Rev. Dis. Primers"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Milella, M.S., Geminiani, M., Trezza, A., Visibelli, A., Braconi, D., and Santucci, A. (2024). Alkaptonuria: From Molecular Insights to a Dedicated Digital Platform. Cells, 13.","DOI":"10.3390\/cells13121072"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.compbiomed.2018.10.002","article-title":"A new integrated and interactive tool applicable to inborn errors of metabolism: Application to alkaptonuria","volume":"103","author":"Spiga","year":"2018","journal-title":"Comput. Biol. Med."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"e27475","DOI":"10.4161\/rdis.27475","article-title":"Alkaptonuria","volume":"1","author":"Mistry","year":"2013","journal-title":"Rare Dis."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Bernini, A., Petricci, E., Atrei, A., Baratto, M.C., Manetti, F., and Santucci, A. (2021). A molecular spectroscopy approach for the investigation of early phase ochronotic pigment development in Alkaptonuria. Sci. Rep., 11.","DOI":"10.1038\/s41598-021-01670-z"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1682","DOI":"10.1016\/j.bbadis.2012.07.011","article-title":"Alkaptonuria is a novel human secondary amyloidogenic disease","volume":"1822","author":"Millucci","year":"2012","journal-title":"Biochim. Biophys. Acta."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"797","DOI":"10.1007\/s10545-015-9842-8","article-title":"Amyloidosis in alkaptonuria","volume":"38","author":"Millucci","year":"2015","journal-title":"J. Inherit. Metab. Dis."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1007\/s11883-020-00901-4","article-title":"High-Density Lipoproteins and Serum Amyloid A (SAA)","volume":"23","author":"Webb","year":"2021","journal-title":"Curr. Atheroscler. Rep."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"745","DOI":"10.1146\/annurev-biochem-072611-130030","article-title":"Systemic amyloidoses","volume":"82","year":"2013","journal-title":"Annu. Rev. Biochem."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"66","DOI":"10.5527\/wjn.v5.i1.66","article-title":"Secondary amyloidosis in autoinflammatory diseases and the role of inflammation in renal damage","volume":"5","author":"Scarpioni","year":"2016","journal-title":"World J. Nephrol."},{"key":"ref_11","first-page":"369","article-title":"Systemic AA amyloidosis: Epidemiology, diagnosis, and management","volume":"6","author":"Costa","year":"2014","journal-title":"Clin. Epidemiol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"16115","DOI":"10.1073\/pnas.1306621110","article-title":"Pathogenetic mechanisms of amyloid A amyloidosis","volume":"110","author":"Simons","year":"2013","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Haines, M.S., Ramirez, E., Moore, K.B., and Fortin, J.S. (2022). Revisiting misfolding propensity of serum amyloid A1, Special focus on the signal peptide region. Biochem. Biophys. Rep., 31.","DOI":"10.1016\/j.bbrep.2022.101284"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"48","DOI":"10.1016\/j.gene.2016.02.044","article-title":"Serum amyloid A1, Structure, function and gene polymorphism","volume":"583","author":"Sun","year":"2016","journal-title":"Gene"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1186\/s10020-018-0047-0","article-title":"Serum amyloid A\u2014A review","volume":"24","author":"Sack","year":"2018","journal-title":"Mol. Med."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Tanaka, M., Takarada, T., Nadanaka, S., Kojima, R., Hosoi, K., Machiba, Y., Kitagawa, H., and Yamada, T. (2023). Influences of amino-terminal modifications on amyloid fibril formation of human serum amyloid A. Arch. Biochem. Biophys., 742.","DOI":"10.1016\/j.abb.2023.109615"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1016\/j.abb.2017.12.016","article-title":"Acceleration of amyloid fibril formation by carboxyl-terminal truncation of human serum amyloid A","volume":"639","author":"Tanaka","year":"2018","journal-title":"Arch. Biochem. Biophys."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"808","DOI":"10.1136\/ard.2004.030429","article-title":"Proteolysis of serum amyloid A and AA amyloid proteins by cysteine proteases: Cathepsin B generates AA amyloid proteins and cathepsin L may prevent their formation","volume":"64","author":"Menard","year":"2005","journal-title":"Ann. Rheum. Dis."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"561","DOI":"10.1016\/S0002-9440(10)61727-0","article-title":"Proteolysis of AA Amyloid Fibril Proteins by Matrix Metalloproteinases-1,-2, and-3","volume":"159","author":"Stix","year":"2001","journal-title":"Am. J. Pathol."},{"key":"ref_20","unstructured":"UniProt Consortium (2023). UniProt: The Universal Protein Knowledgebase in 2023. Nucleic Acids Res., 51, D523\u2013D531."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"5189","DOI":"10.1073\/pnas.1322357111","article-title":"Structural mechanism of serum amyloid A-mediated inflammatory amyloidosis","volume":"111","author":"Lu","year":"2014","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1471","DOI":"10.1093\/bioinformatics\/btaa849","article-title":"PyMod 3, A complete suite for structural bioinformatics in PyMOL","volume":"37","author":"Janson","year":"2021","journal-title":"Bioinformatics"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"283","DOI":"10.1107\/S0021889892009944","article-title":"PROCHECK: A program to check the stereochemical quality of protein structures","volume":"26","author":"Laskowski","year":"1993","journal-title":"J. Appl. Crystallogr."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1859","DOI":"10.1002\/jcc.20945","article-title":"CHARMM-GUI: A web-based graphical user interface for CHARMM","volume":"29","author":"Jo","year":"2008","journal-title":"J. Comput. Chem."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1701","DOI":"10.1002\/jcc.20291","article-title":"GROMACS: Fast, flexible, and free","volume":"26","author":"Lindahl","year":"2005","journal-title":"J. Comput. Chem."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"174778","DOI":"10.1016\/j.ejphar.2022.174778","article-title":"Functional, electrophysiology, and molecular dynamics analysis of quercetin-induced contraction of rat vascular musculature","volume":"918","author":"Trezza","year":"2022","journal-title":"Eur. J. Pharmacol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"583","DOI":"10.1038\/s41586-021-03819-2","article-title":"Highly accurate protein structure prediction with AlphaFold","volume":"596","author":"Jumper","year":"2021","journal-title":"Nature"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"D1373","DOI":"10.1093\/nar\/gkac956","article-title":"PubChem 2023 update","volume":"51","author":"Kim","year":"2023","journal-title":"Nucleic Acids Res."},{"key":"ref_29","first-page":"1","article-title":"Open Babel: An Open chemical toolbox","volume":"3","author":"Banck","year":"2011","journal-title":"J. Cheminform."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1033","DOI":"10.1007\/s00210-016-1266-y","article-title":"In vitro and in silico analysis of the vascular effects of asymmetrical N,N-bis(alkanol)amine aryl esters, novel multidrug resistance-reverting agents","volume":"389","author":"Fusi","year":"2016","journal-title":"Naunyn. Schmiedebergs Arch. Pharmacol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"4233","DOI":"10.1093\/bioinformatics\/btac452","article-title":"DockingPie: A consensus docking plugin for PyMOL","volume":"38","author":"Rosignoli","year":"2022","journal-title":"Bioinformatics"},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Trezza, A., Geminiani, M., Cutrera, G., Dreassi, E., Frusciante, L., Lamponi, S., Spiga, O., and Santucci, A. (2024). A Drug Discovery Approach to a Reveal Novel Antioxidant Natural Source: The Case of Chestnut Burr Biomass. Int. J. Mol. Sci., 25.","DOI":"10.3390\/ijms25052517"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"455","DOI":"10.1002\/jcc.21334","article-title":"AutoDock Vina: Improving the speed and accuracy of docking with a new scoring function, efficient optimization and multithreading","volume":"31","author":"Trott","year":"2010","journal-title":"J. Comput. Chem."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Carullo, G., Ahmed, A., Trezza, A., Spiga, O., Brizzi, A., Saponara, S., Fusi, F., and Aiello, F. (2021). A multitarget semi-synthetic derivative of the flavonoid morin with improved in vitro vasorelaxant activity: Role of CaV1.2 and KCa1.1 channels. Biochem. Pharmacol., 185.","DOI":"10.1016\/j.bcp.2021.114429"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"W443","DOI":"10.1093\/nar\/gkv315","article-title":"PLIP: Fully automated protein\u2013ligand interaction profiler","volume":"43","author":"Salentin","year":"2015","journal-title":"Nucleic Acids Res."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1016\/j.bcp.2017.05.020","article-title":"Cav1.2 channel current block by the PKA inhibitor H-89 in rat tail artery myocytes via a PKA-independent mechanism: Electrophysiological, functional, and molecular docking studies","volume":"140","author":"Fusi","year":"2017","journal-title":"Biochem. Pharmacol."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"362","DOI":"10.1136\/annrheumdis-2014-206033","article-title":"Suitability Of Nitisinone In Alkaptonuria 1 (SONIA 1): An international, multicentre, randomised, open-label, no-treatment controlled, parallel-group, dose-response study to investigate the effect of once daily nitisinone on 24-h urinary homogentisic acid excretion in patients with alkaptonuria after 4 weeks of treatment","volume":"75","author":"Ranganath","year":"2016","journal-title":"Ann. Rheum. Dis."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1093\/rheumatology\/keq246","article-title":"Development of an in vitro model to investigate joint ochronosis in alkaptonuria","volume":"50","author":"Tinti","year":"2011","journal-title":"Rheumatology"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"3103","DOI":"10.1002\/jcp.25761","article-title":"Smoothened-antagonists reverse homogentisic acid-induced alterations of Hedgehog signaling and primary cilium length in alkaptonuria","volume":"232","author":"Gambassi","year":"2017","journal-title":"J. Cell. Physiol."},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Galderisi, S., Milella, M.S., Rossi, M., Cicaloni, V., Rossi, R., Giustarini, D., Spiga, O., Tinti, L., Salvini, L., and Tinti, C. (2022). Homogentisic acid induces autophagy alterations leading to chondroptosis in human chondrocytes: Implications in Alkaptonuria. Arch. Biochem. Biophys., 717.","DOI":"10.1016\/j.abb.2022.109137"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"6011","DOI":"10.1002\/jcp.30284","article-title":"Homogentisic acid induces cytoskeleton and extracellular matrix alteration in alkaptonuric cartilage","volume":"236","author":"Galderisi","year":"2021","journal-title":"J. Cell. Physiol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1728","DOI":"10.1002\/jcp.25500","article-title":"Cytoskeleton Aberrations in Alkaptonuric Chondrocytes","volume":"232","author":"Geminiani","year":"2017","journal-title":"J. Cell. Physiol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"1148","DOI":"10.1002\/jcp.24850","article-title":"Chondroptosis in alkaptonuric cartilage","volume":"230","author":"Millucci","year":"2015","journal-title":"J. Cell. Physiol."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"213","DOI":"10.1111\/j.1365-2818.2006.01706.x","article-title":"A guided tour into subcellular colocalization analysis in light microscopy","volume":"224","author":"Bolte","year":"2006","journal-title":"J. Microsc."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"995","DOI":"10.1038\/nmeth947","article-title":"Direct observation of individual endogenous protein complexes in situ by proximity ligation","volume":"3","author":"Gullberg","year":"2006","journal-title":"Nat. Methods"},{"key":"ref_46","first-page":"4299","article-title":"Serum amyloid P component prevents proteolysis of the amyloid fibrils of Alzheimer disease and systemic amyloidosis","volume":"92","author":"Tennent","year":"1995","journal-title":"Med. Sci."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1080\/13506120500032196","article-title":"Nomenclature Committee of the International Society of Amyloidosis. Amyloid: Toward terminology clarification. Report from the Nomenclature Committee of the International Society of Amyloidosis","volume":"12","author":"Westermark","year":"2005","journal-title":"Amyloid"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/j.bbagen.2016.11.026","article-title":"Homogentisic acid induces aggregation and fibrillation of amyloidogenic proteins","volume":"1861","author":"Braconi","year":"2017","journal-title":"Biochim. Biophys. Acta Gen. Subj."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"209","DOI":"10.3121\/cmr.2.4.209","article-title":"Alkaptonuric Ochronosis with Aortic Valve and Joint Replacements and Femoral Fracture: A Case Report and Literature Review","volume":"2","author":"Fisher","year":"2004","journal-title":"Clin. Med. Res."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"107","DOI":"10.1016\/j.coph.2015.04.002","article-title":"Lessons from rare diseases of cartilage and bone","volume":"22","author":"Gallagher","year":"2015","journal-title":"Curr. Opin. Pharmacol."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"922","DOI":"10.1002\/jcb.22780","article-title":"Proteomic and redox-proteomic evaluation of homogentisic acid and ascorbic acid effects on human articular chondrocytes","volume":"111","author":"Braconi","year":"2010","journal-title":"J. Cell Biochem."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"258471","DOI":"10.1155\/2014\/258471","article-title":"Amyloidosis, inflammation, and oxidative stress in the heart of an alkaptonuric patient","volume":"2014","author":"Millucci","year":"2014","journal-title":"Mediators Inflamm."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"3333","DOI":"10.1002\/jcp.24033","article-title":"Biochemical and proteomic characterization of alkaptonuric chondrocytes","volume":"227","author":"Braconi","year":"2012","journal-title":"J. Cell Physiol."},{"key":"ref_54","doi-asserted-by":"crossref","unstructured":"Lee, J., and Beatty, G.L. (2021). Serum Amyloid A Proteins and Their Impact on Metastasis and Immune Biology in Cancer. Cancers, 13.","DOI":"10.3390\/cancers13133179"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1186\/s12935-019-0783-4","article-title":"The prognostic value of serum amyloid A in solid tumors: A meta-analysis","volume":"19","author":"Lin","year":"2019","journal-title":"Cancer Cell Int."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1007\/s00018-008-8321-x","article-title":"Serum amyloid A: An acute-phase protein involved in tumour pathogenesis","volume":"66","author":"Malle","year":"2009","journal-title":"Cell. Mol. Life Sci."},{"key":"ref_57","first-page":"339","article-title":"Why do cancer cells produce serum amyloid A acute-phase protein?","volume":"77","author":"Moshkovskii","year":"2012","journal-title":"Biochemistry"},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1021\/bi0620959","article-title":"Plasticity of amyloid fibrils","volume":"46","author":"Wetzel","year":"2007","journal-title":"Biochemistry"}],"container-title":["Cells"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4409\/13\/17\/1501\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T15:50:14Z","timestamp":1760111414000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4409\/13\/17\/1501"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,9,7]]},"references-count":58,"journal-issue":{"issue":"17","published-online":{"date-parts":[[2024,9]]}},"alternative-id":["cells13171501"],"URL":"https:\/\/doi.org\/10.3390\/cells13171501","relation":{},"ISSN":["2073-4409"],"issn-type":[{"value":"2073-4409","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,9,7]]}}}