Placental transfer of long-chain polyunsaturated fatty acids (LC-PUFA)

Considerable evidence exists for marked beneficial effects of omega-3 long-chain polyunsaturated fatty acids (LC-PUFA) during pregnancy. The omega-3 LCPUFA docosahexaenoic acid (DHA) is incorporated in large amounts in fetal brain and other tissues during the second half of pregnancy, and several studies have provided evidence for a link between early DHA status of the mother and visual and cognitive development of her child after birth. Moreover, the supplementation of omega-3 LC-PUFA during pregnancy increases slightly infant size at birth, and significantly reduces early preterm birth before 34 weeks of gestation by 31%. In our studies using stable isotope methodology in vivo, we demonstrated active and preferential materno-fetal transfer of DHA across the human placenta and found the expression of human placental fatty acid binding and transport proteins. From the correlation of DHA values with placental fatty acid transport protein 4 (FATP 4), we conclude that this protein is of key importance in mediating DHA transport across the human placenta. Given the great importance of placental DHA transport for infant outcome, further studies are needed to fully appreciate the effects and optimal strategies of omega-3 fatty acid interventions in pregnancy, dose response relationships, and the potential differences between subgroups of subjects such as women with gestational diabetes or other gestational pathology. Such studies should contribute to optimize substrate intake during pregnancy and lactation that may improve pregnancy outcome as well as fetal growth and development

Essential fatty acids and their long-chain polyunsaturated metabolites in maternal and cord plasma triglycerides during late gestation

The fatty acid composition of plasma lipids was determined in 41 pairs of mothers and their term infants at time of birth (38-42 postmenstrual weeks) by high-resolution capillary gas-liquid chromatography, Linoleic and alpha-linolenic acids were found at smaller concentrations in cord than in maternal triglycerides, in contrast to strikingly higher proportions of their long-chain polyunsaturated metabolites (IC-PUFA), which indicates a preferential maternofetal transport for certain physiologically important LC-PUFA. While no significant gestational age-dependent changes occurred in maternal plasma triglycerides, the values for most of the fetal long-chain n-3 metabolites increased with the duration of gestation, possibly reflecting an increased transplacental fatty acid passage during late pregnancy or a maturation of desaturation in the fetal liver, Copyright (C) 2000 S. Karger AG, Basel

Oxidation of an oil rich in docosahexaenoic acid compared to linoleic acid in lactating women

Background: We studied the oxidation of an oil rich in docosahexaenoic acid (DHA; DHASCO(R)) in lactating mothers receiving a dietary DHA supplement or a placebo. The results were compared with the oxidation of linoleic acid. Methods: Breast-feeding mothers received a dietary supplement (DHASCO; 200 mg DHA/day, n = 5) or a placebo (n = 5) for 14 days. Six weeks post partum all 10 mothers received a single dose of 2 mg/kg body weight uniformly C-13-labeled DHASCO. In a previously reported study 6 mothers received 1 mg/kg body weight uniformly C-13-labeled linoleic acid. Breath samples were collected over 48 h after tracer application. The total CO2 production was measured by indirect calorimetry and the C-13 isotopic enrichment of labeled CO2 by isotopic ratio mass spectrometry. Results: The oxidation of C-13-labeled DHASCO in the supplemented and placebo groups was similar. Maximal C-13 enrichment was reached earlier in the group receiving C-13-DHASCO (median 1.0 vs. 3.0 h in the linoleic acid group). The cumulative C-13 recovery in breath was higher in the DHASCO versus the linoleic acid group until 10 h after tracer application and comparable thereafter. Conclusions: The difference in oxidation of DHASCO versus linoleic acid after tracer ingestion might be partly due to a faster absorption and oxidation of shorter chain saturated fatty acids contained in DHASCO. The cumulative oxidation of DHASCO and linoleic acid 24 and 48 h after tracer ingestion is similar. Copyright (C) 2000 S. Karger AG, Basel

High-Throughput Analysis of Total Plasma Fatty Acid Composition with Direct In Situ Transesterification

Plasma fatty acid (FA) composition reflects dietary intake and endogenous turnover and is associated with health outcomes on a short and long term basis. The total plasma FA pool represents the composition of all FA containing lipid fractions. We developed a simplified and affordable high-throughput method for the analysis of total plasma FA composition, suitable for large studies. The total lipid FA from 100 microl plasma is transferred in situ into methyl esters, avoiding initial extraction and drying steps. The fatty acid methyl esters are extracted once and analyzed by gas chromatography. For the new direct in situ transesterification method optimal, reaction parameters were determined. Intra-assay analysis (n=8) revealed coefficients of variation below 4% for FA contributing more than 1% to total FA. The results show good agreement with FA concentrations obtained by a reference method. The new direct in situ transesterification method is robust and simple. Sample preparation time and analysis costs are reduced to a minimum. This method is an economically and ecologically superior alternative to conventional methods for assessing plasma FA status in large studies