Fatty acid status and antioxidant defense system in mothers and their newborns after salmon intake during late pregnancy.

OBJECTIVE: The aim of the present study was to assess the maternal and newborn status of erythrocyte fatty acids and the antioxidant defense system after the intake of two portions of salmon per week during late pregnancy. METHODS: Pregnant women (N = 123) were randomly assigned to continue their habitual diet, which was low in oily fish (control group, n = 61) or to consume two 150-g salmon portions per week (salmon group, n = 62) beginning at 20 wk of gestation and lasting until delivery. Fatty acids, selenium, and glutathione concentrations and antioxidant defense enzyme activities were measured in maternal erythrocytes at 20, 34, and 38 wk of pregnancy, and in cord erythrocytes collected at birth. Plasma concentrations of antioxidant molecules were measured. RESULTS: Compared with the control group, consuming salmon had little effect on erythrocyte fatty acids in either mothers or newborns. Components of the antioxidant defense system did not differ between groups. Glutathione peroxidase activity and the concentrations of tocopherols, retinol, and coenzyme Q10 were significantly lower in cord blood compared with maternal blood at week 38 in both groups. CONCLUSION: Maternal and newborn erythrocyte fatty acids are not strongly affected by the intake of two portions of salmon per week during the second half of pregnancy, although erythrocyte docosahexaenoic acid might be increased in newborns. Maternal and newborn antioxidant defense systems are not impaired by intake of salmon from 20 wk gestation.

Increased intake of oily fish in pregnancy: effects on neonatal immune responses and on clinical outcomes in infants at 6 mo.

BACKGROUND: Long-chain n-3 PUFAs found in oily fish may have a role in lowering the risk of allergic disease. OBJECTIVE: The objective was to assess whether an increased intake of oily fish in pregnancy modifies neonatal immune responses and early markers of atopy. DESIGN: Women (n = 123) were randomly assigned to continue their habitual diet, which was low in oily fish, or to consume 2 portions of salmon per week (providing 3.45 g EPA plus DHA) from 20 wk gestation until delivery. In umbilical cord blood samples (n = 101), we measured n-3 fatty acids, IgE concentrations, and immunologic responses. Infants were clinically evaluated at age 6 mo (n = 86). RESULTS: Cord blood mononuclear cell (CBMC) production of interleukin (IL)-2, IL-4, IL-5, IL-10, and tumor necrosis factor-α in response to phytohemagglutinin (PHA) and of IL-2 in response to Dermatophagoides pteronyssinus allergen 1 (Derp1) was lower in the salmon group (all P ≤ 0.03). In the subgroup of CBMCs in which an allergic phenotype was confirmed in the mother or father, IL-10 production in response to Toll-like receptor 2, 3, and 4 agonists, ovalbumin, salmon parvalbumin, or Derp1 and prostaglandin E(2) production in response to lipopolysaccharide or PHA was lower in the salmon group (all P ≤ 0.045). Total IgE at birth and total IgE, incidence and severity of atopic dermatitis, and skin-prick-test positivity at 6 mo of age were not different between the 2 groups. CONCLUSION: Oily fish intervention in pregnancy modifies neonatal immune responses but may not affect markers of infant atopy assessed at 6 mo of age. This trial is registered at clinicaltrials.gov as NCT00801502.

Does consumption of two portions of salmon per week enhance the antioxidant defense system in pregnant women?

Salmon is a rich source of marine n-3 fatty acids, which may increase oxidative stress and, in turn, could affect the antioxidant defense system in blood plasma and erythrocytes of pregnant women. The Salmon in Pregnancy Study provided two meals of salmon per week to pregnant women from week 20 of gestation; the control group maintained their habitual diet low in oily fish. Higher selenium and retinol plasma concentrations were observed after dietary salmon supplementation. Besides, a concomitant increase in selenium and glutathione concentration as well as glutathione peroxidase and reductase activities were detected as pregnancy progressed. However, tocopherols, retinol, ß-carotene, and coenzyme Q(10) decreased in late pregnancy. Collectively, our findings lead to the hypothesis that increased farmed salmon intake may increase antioxidant defenses during pregnancy. Clinical trials identifier NCT00801502.

Phenotypic analysis of circulating dendritic cells during the second half of human gestation.

Dendritic cells (DCs) have been characterized as having an immature phenotype in infants when compared with adults; but it is unclear whether the phenotype or function of these populations changes during human intrauterine development. Three-colour flow cytometry was used to phenotype fetal/neonatal circulating DCs during the second half (>20-wk gestation) of pregnancy, (n = 34) and adults (n = 9). DCs were identified from peripheral blood mononuclear cells (PBMCs) or cord blood mononuclear cells (CBMCs) as staining brightly for HLA-DR but negative for T cell, B cell, monocyte, and NK cell lineage markers. The surface molecule of interest was detected in a third colour. During gestation CD34, a marker of immaturity was significantly higher, and CD4, a differentiation marker, was significantly lower than adult levels. The percentage of CD11c+ cells did not differ significantly at any age, although a trend to reduced intensity of expression at earlier stages of gestation was observed. Significantly fewer DCs expressed the IgG receptors CD32 and CD64 at all gestations. The percentage of HLA-DR+/lin- cells expressing CD40 was lowest at 20-23 wks and was always significantly lower on DCs from cord blood vs. adult blood. Similarly, the percentage of CD86+ and CD54+ DCs was significantly lower than adults throughout gestation. Thus, immaturity of cord blood DCs is likely to arise as a consequence of decreased ability to take up antigen (at least via IgG-mediated mechanisms) and reduced provision of co-stimulation.