{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T02:47:21Z","timestamp":1792464441045,"version":"4.5.0"},"reference-count":0,"publisher":"S. Karger AG","issue":"1","license":[{"start":{"date-parts":[[2018,8,15]],"date-time":"2018-08-15T00:00:00Z","timestamp":1534291200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.karger.com\/Services\/SiteLicenses"},{"start":{"date-parts":[[2018,8,15]],"date-time":"2018-08-15T00:00:00Z","timestamp":1534291200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.karger.com\/Services\/SiteLicenses"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Neuropsychobiology"],"published-print":{"date-parts":[[2019]]},"abstract":"<b><i>Background:<\/i><\/b> Some previous studies found decreased concentrations of L-tryptophan (TRY) and increased L-kynurenine (KYN), or its metabolites, in the body fluids of subjects with major depressive disorder (MDD), sometimes in association with suicidal behavior. Such changes might indicate a shift of TRY away from serotonin production, possibly via the effects of inflammatory peptides which activate indoleamine-2,3-dioxygenase. However, these findings have been inconsistent and require replication. <b><i>Methods:<\/i><\/b> We used sensitive liquid-chromatography mass spectrometry methods to assay plasma concentrations of TRY, 5-hydroxyindoleacetic acid (5-HIAA), and KYN and its metabolites (anthranilic acid and xanthurenic acid). We compared 49 hospitalized, depressed subjects diagnosed with MDD (<i>n<\/i> = 37) or bipolar disorder (BD, <i>n<\/i> = 12), with (<i>n<\/i> = 22) or without (<i>n<\/i> = 27) previous suicide attempts, to 78 healthy, ambulatory controls of similar age and sex (total <i>n<\/i> = 127). <b><i>Findings:<\/i><\/b> Contrary to expectation, TRY plasma concentrations were higher, KYN plasma concentrations were lower, and their ratio much higher in depressed subjects, with no relationship to suicidal history. Concentrations of 5-HIAA and the kynurenine metabolites did not differ between depressed and healthy subjects. <b><i>Conclusions:<\/i><\/b> These findings are opposite to expectations and not consistent with a hypothesized increased conversion from TRY to KYN in depressed subjects. In addition, we found no evidence of altered production of serotonin as 5-HIAA concentration was unchanged. None of the observed changes was associated with a history of suicide attempt.<\/jats:p>","DOI":"10.1159\/000491604","type":"journal-article","created":{"date-parts":[[2018,8,16]],"date-time":"2018-08-16T21:01:22Z","timestamp":1534453282000},"page":"23-28","source":"Crossref","is-referenced-by-count":37,"title":["Tryptophan and Kynurenine Metabolites: Are They Related to Depression?"],"prefix":"10.1159","volume":"77","author":[{"given":"Maurizio","family":"Pompili","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luana","family":"Lionetto","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martina","family":"Curto","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto","family":"Forte","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Denise","family":"Erbuto","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Franco","family":"Montebovi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria\u00a0Elena","family":"Seretti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Isabella","family":"Berardelli","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gianluca","family":"Serafini","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marco","family":"Innamorati","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mario","family":"Amore","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ross\u00a0J.","family":"Baldessarini","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paolo","family":"Girardi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maurizio","family":"Simmaco","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"127","published-online":{"date-parts":[[2018,8,15]]},"container-title":["Neuropsychobiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.karger.com\/Article\/Pdf\/491604","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.karger.com\/Article\/Pdf\/491604","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,4,23]],"date-time":"2025-04-23T16:46:58Z","timestamp":1745426818000},"score":1,"resource":{"primary":{"URL":"https:\/\/karger.com\/article\/doi\/10.1159\/000491604"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,8,15]]},"references-count":0,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2018,11,22]]},"published-print":{"date-parts":[[2018,11,27]]}},"URL":"https:\/\/doi.org\/10.1159\/000491604","archive":["Portico"],"relation":{},"ISSN":["0302-282X","1423-0224"],"issn-type":[{"value":"0302-282X","type":"print"},{"value":"1423-0224","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,8,15]]}}}