Predictors of oxylipins in a healthy pediatric population

BACKGROUND: Oxylipins are formed from oxidation of omega-6 (n6) and omega-3 (n3) fatty-acids (FA). Evidence for inflammatory effects comes mostly from adults. METHODS: Oxylipins from n6-FA (27 n6-oxylipins) and n3-FA (12 n3-oxylipins) were measured through ultra-high-performance liquid chromatography-mass spectrometry (LC-MS/MS) in plasma from 111 children at risk of type 1 diabetes (age 1–17 years) studied longitudinally. Oxylipin precursor FA (arachidonic acid, linoleic acid, alpha-linolenic acid, docosahexaenoic acid, and eicosapentaenoic acid) were measured in red blood cell (RBC) membrane and plasma. Precursor FA dietary intake was measured through food frequency questionnaire and environmental tobacco smoke (ETS) through questionnaires. Linear mixed models were used to test oxylipins with predictors. RESULTS: Age associated with 15 n6- and 6 n3-oxylipins; race/ethnicity associated with 3 n6- and 1 n3-oxylipins; sex associated with 2 n6-oxylipins. ETS associated with lipoxin-A4. Oxylipins associated with precursor FA in plasma more often than RBC. RBC levels and dietary intake of precursor FA more consistently associated with n3- than n6-oxylipins. CONCLUSIONS: In healthy children, oxylipin levels change with age. Oxylipins are associated with precursor FA more often in plasma than RBC or diet, suggesting that inflammatory regulation leading to FA release into plasma may also be a determinant of oxylipin generation