{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T04:34:28Z","timestamp":1791174868681,"version":"4.1.0"},"reference-count":42,"publisher":"Oxford University Press (OUP)","issue":"1","license":[{"start":{"date-parts":[[2013,6,6]],"date-time":"2013-06-06T00:00:00Z","timestamp":1370476800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"funder":[{"DOI":"10.13039\/501100005416","name":"Norwegian Research Council","doi-asserted-by":"crossref","award":["204650"],"award-info":[{"award-number":["204650"]}],"id":[{"id":"10.13039\/501100005416","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Foundation to Promote Research into Functional Vitamin B12 Deficiency"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2013,6,6]]},"abstract":"<jats:title>Summary<\/jats:title>\n               <jats:p>Circulating neopterin and kynurenine\/tryptophan ratio (KTR) increase during inflammation and serve as markers of cellular immune activation, but data are sparse on other determinants of these markers and metabolites of the kynurenine pathway. We measured neopterin, tryptophan, kynurenine, anthranilic acid, kynurenic acid, 3-hydroxykynurenine, 3-hydroxyanthranilic acid and xanthurenic acid in plasma in two age groups, 45\u201346 years (n\u2009=\u20093723) and 70\u201372 years (n\u2009=\u20093329). Differences across categories of the potential determinants, including age, gender, renal function, body mass index (BMI), smoking and physical activity, were tested by Mann\u2013Whitney U-test and multiple linear regression including age group, gender, renal function and lifestyle factors. In this multivariate model, neopterin, KTR and most kynurenines were 20\u201330% higher in the older group, whereas tryptophan was 7% lower. Men had 6\u201319% higher concentrations of tryptophan and most kynurenines than women of the same age. Compared to the fourth age-specific estimated glomerular filtration rate (eGFR) quartile, the first quartile was associated with higher concentrations of neopterin (25%) and KTR (24%) and 18\u201336% higher concentrations of kynurenines, except 3-hydroxyanthranilic acid. Additionally, KTR, tryptophan and all kynurenines, except anthranilic acid, were 2\u20138% higher in overweight and 3\u201317% higher in obese, than in normal-weight individuals. Heavy smokers had 4\u201314% lower levels of tryptophan and most kynurenines than non-smokers. Age and renal function were the strongest determinants of plasma neopterin, KTR and most kynurenines. These findings are relevant for the design and interpretation of studies investigating the role of plasma neopterin, KTR and kynurenines in chronic diseases.<\/jats:p>","DOI":"10.1111\/cei.12092","type":"journal-article","created":{"date-parts":[[2013,2,25]],"date-time":"2013-02-25T07:04:52Z","timestamp":1361775892000},"page":"121-130","source":"Crossref","is-referenced-by-count":120,"title":["A community-based study on determinants of circulating markers of cellular immune activation and kynurenines: the Hordaland Health Study"],"prefix":"10.1093","volume":"173","author":[{"given":"D","family":"Theofylaktopoulou","sequence":"first","affiliation":[{"name":"Section for Pharmacology, Institute of Medicine, University of Bergen, Norway"},{"name":"Department of Public Health and Primary Health Care, University of Bergen, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"\u00d8","family":"Midttun","sequence":"additional","affiliation":[{"name":"Bevital AS, Bergen, 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