Environmental determinants of serum selenoproteins concentrations and composition in the Aragon Workers Health Study - SelenOmics project.

Background: Identifying potencial determinants of serum selenoproteins and selenometabolites can help understanding selenium-related metabolism and health consequences. We evaluated the cross-sectional association between environmental factors and serum selenoproteins and total selenometabolites concentration and composition in the Aragon Workers Health Study (AWHS), a participating cohort in the SelenOmics project. Materials and methods. Serum selenoproteins (glutathione peroxidase [GPx], selenoprotein P [SeP], selenoalbumin [SeAlb]), selenometabolites (Se-metabolites) and total selenium and urine metals were measured using HPLC/ICP-MS in 862 AWHS participants. We estimated a Healthy Lifestyle Score (HLS), which included diet, physical activity, smoking, BMI and alcohol consumption. Selenoproteins and Se-metabolites concentrations (log-transformed) and composition (logit-transformed specific species proportion) were introduced as dependent variables in linear regression models adjusted by age, sex and education. Results. Serum GPx, SeP, SeAlb, total Se-metabolites and selenium median concentrations were, 15.82, 66.07, 14.04, 0.07 and 96.44 µg/L, respectively. We observed statistically significant associations [GMR (95% CI), two-fold change for continuous variables] between ever smoking [0.96(0.93,0.99)], HLS [1.02(1.00,1.05)], total serum selenium [1.08(1.04,1.13)] and tungsten [1.03(1.01,1.05)] with GPx and tungsten with GPx% [1.04(1.02,1.06)]; arsenobetain-corrected arsenic [1.01(1.00,1.02)], chromium [0.98(0.97,1.00)] and total selenium [1.13(1.09,1.16)] with SeP, and age[1.07(1.01,1.13], ever smoking [1.04(1.00,1.07)] and HLS [0.98(0.95,1.00)] for SeP%; ever smoking [0.93(0.90,0.97)], HLS [1.03(1.01,1.06)], BMI [0.81(0.69,0.94)], arsenic [1.02(1.00,1.03)], chromium [1.03(1.00,1.05)] and total selenium [1.10(1.05,1.15)] with SeAlb, and ever smoking [0.95(0.92,0.99)], chromium [1.04(1.01,1.07)] and vanadium [0.96(0.93,1.00)] with SelAlb%; and sex [1.80(1.13,2.89)], physical activity [1.17(1.01,1.38)] and tungsten [0.91(0.85,0.97)] with Se-metabolites and sex[1.68(1.04,2.69)], tungsten [0.92(0.86,0.98)] and selenium[0.84(0.73,0.96)] with Se-metabolites%. The association of tungsten with GPx, selenium with SeP, smoking and BMI with SeAlb, and sex with Se-metabolites, remained after additional adjustment for statistically significant determinants. Conclusion. Serum selenoproteins and selenometabolites concentrations and composition were associated with several environmental determinants, which support that the environment play a relevant role in selenium-related metabolic pathways. Keywords: selenium, selenoproteins, selenometabolites, environmental determinants