Increased vitamin E intake is associated with higher alpha-tocopherol concentration in the maternal circulation but higher alpha-carboxyethyl hydroxychroman concentration in the fetal circulation.

摘要

BACKGROUND: The transfer of vitamin E across the placenta is limited, but no data exist on the concentrations of vitamin E metabolites carboxyethyl hydroxychromans (alpha- and gamma-CEHCs) in the fetal circulation. OBJECTIVE: We measured alpha- and gamma-CEHC concentrations in maternal and umbilical cord blood pairs and examined their relations to circulating vitamin E (alpha- and gamma-tocopherol) and maternal dietary vitamin E intake. DESIGN: Healthy, pregnant women were enrolled from Oregon Health and Science University's obstetric clinic (<22 wk gestation), and at least one fasting blood sample and a previous day's 24-h diet recall were collected during their pregnancy (n = 19). Umbilical cord blood samples were obtained at the time of delivery and were analyzed for alpha- and gamma-tocopherol, alpha- and gamma-CEHC, and total lipid concentrations. RESULTS: Mean (+/-SD) concentrations of umbilical cord blood alpha-CEHC (30.2 +/- 28.9 nmol/L) and gamma-CEHC (104.5 +/- 61.3 nmol/L) were not significantly different from maternal concentrations (P = 0.07 and 0.08, respectively), but metabolite:tocopherol ratios were significantly higher in cord blood (P < 0.01 and 0.001, respectively). Maternal alpha-tocopherol:total lipids ratios were correlated with cord blood alpha-CEHCs (r = 0.67, P = 0.004), and higher vitamin E intakes were associated with higher cord blood alpha-CEHC concentrations (r = 0.75, P < 0.003). CONCLUSION: Higher maternal intake of vitamin E during pregnancy may result in increased metabolite concentrations in the fetal circulation, suggesting increased maternal or fetal liver metabolism of vitamin E. This trial was registered at clinicaltrials.gov as NCT00632476.