{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T01:20:32Z","timestamp":1790644832984,"version":"4.1.0"},"reference-count":79,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2020,4,8]],"date-time":"2020-04-08T00:00:00Z","timestamp":1586304000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004587","name":"Instituto de Salud Carlos III","doi-asserted-by":"publisher","award":["PI18\/00118"],"award-info":[{"award-number":["PI18\/00118"]}],"id":[{"id":"10.13039\/501100004587","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010774","name":"Consejer\u00eda de Educaci\u00f3n e Investigaci\u00f3n","doi-asserted-by":"publisher","award":["S2017\/BMD-3700"],"award-info":[{"award-number":["S2017\/BMD-3700"]}],"id":[{"id":"10.13039\/501100010774","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004837","name":"Ministerio de Ciencia e Innovaci\u00f3n","doi-asserted-by":"publisher","award":["CTQ2011-29163-C03-01"],"award-info":[{"award-number":["CTQ2011-29163-C03-01"]}],"id":[{"id":"10.13039\/501100004837","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>Kynurenic acid (KYNA) is a product of the tryptophan (TRP) metabolism via the kynurenine pathway (KP). This pathway is activated in neurodegenerative disorders, such as Alzheimer\u00b4s disease (AD). KYNA is primarily produced by astrocytes and is considered neuroprotective. Thus, altered KYNA levels may suggest an inflammatory response. Very recently, significant increases in KYNA levels were reported in cerebrospinal fluid (CSF) from AD patients compared with normal controls. In this study, we assessed the accuracy of KYNA in CSF for the classification of patients with AD, cognitively healthy controls, and patients with a variety of other neurodegenerative diseases, including frontotemporal dementia (FTD), amyotrophic lateral sclerosis (ALS), and progressive supranuclear palsy (PSP). Averaged KYNA concentration in CSF was higher in patients with AD when compared with healthy subjects and with all the other differentially diagnosed groups. There were no significant differences in KYNA levels in CSF between any other neurodegenerative groups and controls. These results suggest a specific increase in KYNA concentration in CSF from AD patients not seen in other neurodegenerative diseases.<\/jats:p>","DOI":"10.3390\/biom10040571","type":"journal-article","created":{"date-parts":[[2020,4,9]],"date-time":"2020-04-09T03:40:19Z","timestamp":1586403619000},"page":"571","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":80,"title":["Kynurenic Acid Levels are Increased in the CSF of Alzheimer\u2019s Disease Patients"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9155-1438","authenticated-orcid":false,"given":"Marta","family":"Gonz\u00e1lez-S\u00e1nchez","sequence":"first","affiliation":[{"name":"Group of Neurodegenerative Diseases, Hospital 12 de Octubre Research Institute (imas12), 28041 Madrid, Spain"},{"name":"Biomedical Research Networking Center in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Javier","family":"Jim\u00e9nez","sequence":"additional","affiliation":[{"name":"Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcal\u00e1, 28871 Alcal\u00e1 de Henares, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arantzazu","family":"Narv\u00e1ez","sequence":"additional","affiliation":[{"name":"Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcal\u00e1, 28871 Alcal\u00e1 de Henares, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Desiree","family":"Antequera","sequence":"additional","affiliation":[{"name":"Group of Neurodegenerative Diseases, Hospital 12 de Octubre Research Institute (imas12), 28041 Madrid, Spain"},{"name":"Biomedical Research Networking Center in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sara","family":"Llamas-Velasco","sequence":"additional","affiliation":[{"name":"Group of Neurodegenerative Diseases, Hospital 12 de Octubre Research Institute (imas12), 28041 Madrid, Spain"},{"name":"Biomedical Research Networking Center in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alejandro Herrero-San","family":"Mart\u00edn","sequence":"additional","affiliation":[{"name":"Group of Neurodegenerative Diseases, Hospital 12 de Octubre Research Institute (imas12), 28041 Madrid, Spain"},{"name":"Biomedical Research Networking Center in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jose Antonio","family":"Molina Arjona","sequence":"additional","affiliation":[{"name":"Group of Neurodegenerative Diseases, Hospital 12 de Octubre Research Institute (imas12), 28041 Madrid, Spain"},{"name":"Biomedical Research Networking Center in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9509-4032","authenticated-orcid":false,"given":"Adolfo","family":"L\u00f3pez de Munain","sequence":"additional","affiliation":[{"name":"Biomedical Research Networking Center in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain"},{"name":"Neurosciences Research Area, Biodonostia Health Research Institute, 20014 San Sebastian, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto","family":"Lle\u00f3 Bisa","sequence":"additional","affiliation":[{"name":"Biomedical Research Networking Center in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain"},{"name":"Neurology Department, Hospital de la Santa Creu i Sant Pau, 08041 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M.-Pilar","family":"Marco","sequence":"additional","affiliation":[{"name":"Nanobiotechnology for Diagnostics (Nb4D) Group, Institute for Advanced Chemistry of Catalonia (IQAC), Spanish National Research Council (CSIC), 08034 Barcelona, Spain"},{"name":"Centro de Investigaci\u00f3n Biom\u00e9dica en Red (CIBER) de Bioingenier\u00eda, Biomateriales y Nanomedicina (CIBER-BBN), 08034 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Montserrat","family":"Rodr\u00edguez-N\u00fa\u00f1ez","sequence":"additional","affiliation":[{"name":"Nanobiotechnology for Diagnostics (Nb4D) Group, Institute for Advanced Chemistry of Catalonia (IQAC), Spanish National Research Council (CSIC), 08034 Barcelona, Spain"},{"name":"Centro de Investigaci\u00f3n Biom\u00e9dica en Red (CIBER) de Bioingenier\u00eda, Biomateriales y Nanomedicina (CIBER-BBN), 08034 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David Andr\u00e9s","family":"P\u00e9rez-Mart\u00ednez","sequence":"additional","affiliation":[{"name":"Group of Neurodegenerative Diseases, Hospital 12 de Octubre Research Institute (imas12), 28041 Madrid, Spain"},{"name":"Biomedical Research Networking Center in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6834-7620","authenticated-orcid":false,"given":"Alberto","family":"Villarejo-Galende","sequence":"additional","affiliation":[{"name":"Group of Neurodegenerative Diseases, Hospital 12 de Octubre Research Institute (imas12), 28041 Madrid, Spain"},{"name":"Biomedical Research Networking Center in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9322-8933","authenticated-orcid":false,"given":"Fernando","family":"Bartolome","sequence":"additional","affiliation":[{"name":"Group of Neurodegenerative Diseases, Hospital 12 de Octubre Research Institute (imas12), 28041 Madrid, Spain"},{"name":"Biomedical Research Networking Center in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"Dom\u00ednguez","sequence":"additional","affiliation":[{"name":"Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, University of Alcal\u00e1, 28871 Alcal\u00e1 de Henares, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eva","family":"Carro","sequence":"additional","affiliation":[{"name":"Group of Neurodegenerative Diseases, Hospital 12 de Octubre Research Institute (imas12), 28041 Madrid, Spain"},{"name":"Biomedical Research Networking Center in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"657","DOI":"10.14740\/jocmr2106w","article-title":"The Epidemiological Scale of Alzheimer\u2019s Disease","volume":"7","author":"Cornutiu","year":"2015","journal-title":"J. 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