{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T05:15:27Z","timestamp":1788412527714,"version":"build-2803163510"},"reference-count":32,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,10,18]],"date-time":"2023-10-18T00:00:00Z","timestamp":1697587200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Innlandet Hospital Trust, Brumunddal, Norway and Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>Background: APOE polymorphism and the Kynurenine pathway (KP) are associated with many disorders, but little is known about associations between APOE polymorphism and the KP. This study explored the associations between the KP and APOE polymorphism in disorders associated with APOE polymorphism and changes in the KP. Methods: Subjects with morbid obesity before and after bariatric surgery (numbers 139 and 95, respectively), depression (number 49), and unspecified neurological symptoms (number 39) were included. The following grouping of the APOE genotypes was used: E2 = \u025b2\u025b2 + \u025b2\u025b3, E3 = \u025b3\u025b3 + \u025b2\u025b4, and E4 = \u025b3\u025b4 + \u025b4\u025b4. The KP metabolites Tryptophan, Kynurenine, Kynurenic acid, Quinolinic acid, and Xanthurenic acid were quantified in serum. Results: The main findings were a significant positive association between E3 and Quinolinic acid (difference between E3 and E2E4: 12.0 (3.5; 18.6) ng\/mL); p = 0.005), and a negative association between E4 and Kynurenine (difference between E4 and E2E3: \u221231.3 (\u221254.2; \u22123.2) ng\/mL; p = 0.008). Quinolinic acid has been ascribed neurotoxic and inflammatory effects, and Kynurenine is a marker of inflammation. Conclusions: The findings indicate that APOE polymorphism might cause changes in the KP that contribute to the disease. Inflammation could be the link between APOE and the KP.<\/jats:p>","DOI":"10.3390\/genes14101955","type":"journal-article","created":{"date-parts":[[2023,10,18]],"date-time":"2023-10-18T09:55:06Z","timestamp":1697622906000},"page":"1955","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["APOE Polymorphism Is Associated with Changes in the Kynurenine Pathway"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5627-1641","authenticated-orcid":false,"given":"Per G.","family":"Farup","sequence":"first","affiliation":[{"name":"Department of Research, Innlandet Hospital Trust, 2381 Brumunddal, Norway"},{"name":"Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, 7491 Trondheim, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5862-1745","authenticated-orcid":false,"given":"Helge","family":"Rootwelt","sequence":"additional","affiliation":[{"name":"Department of Medical Biochemistry, Oslo University Hospital, 0424 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Knut","family":"Hestad","sequence":"additional","affiliation":[{"name":"Department of Research, Innlandet Hospital Trust, 2381 Brumunddal, Norway"},{"name":"Department of Psychology, Faculty of Social and Educational Sciences, Norwegian University of Science and Technology, 7491 Trondheim, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Hubkova, B., Valko-Rokytovska, M., Cizmarova, B., Zabavnikova, M., Marekova, M., and Birkova, A. 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