Longitudinal assessment of erythrocyte fatty acid composition throughout pregnancy and post partum

Growth patterns in infants born to women with pregestational overweight/obesity supplemented with docosahexaenoic acid during pregnancy

BACKGROUND

Previous studies of maternal docosahexaenoic acid (DHA) supplementation during pregnancy have controversial and contrasting results on the short and long-term effects on early child growth. The impact of this nutritional intervention on the postnatal growth patterns in the offspring of women with pregestational overweight/obesity (PGO) also remains controversial.

OBJECTIVE

To analyze the postnatal growth patterns during the first 4 months of life in the offspring of women with PGO randomly supplemented with 800 mg/day (PGO-800) compared with normative doses of 200 mg/day (PGO-200) of DHA during pregnancy (<15 weeks of gestation until delivery).

METHODS

This study evaluated the growth patterns during the first 4 months of life of 169 infants of the women that participated in the MIGHT study (NCT02574767). We included the infants of women from the PGO-200 (n = 81) and PGO-800 group (n = 88). The growth patterns (weight, length, and head circumference) and change in z-score (WHO charts) were evaluated.

RESULTS

Throughout the first 4 months of life, the infants of the PGO-800 group had lower weight-for-length z-score (coef. -0.65, 95% confidence interval [CI] -1.07, -0.22, p = 0.003) and lower body mass index-for-age z-score (coef. -0.56, 95% CI -0.99, -0.12, p = 0.012) compared with the PGO-200 group adjusted by maternal body mass index, gestational weight gain, gestational age, insulin in cord blood and infant feeding (exclusive breastfed, not breastfed, and partially breastfed).

CONCLUSIONS

Maternal supplementation with DHA during pregnancy could beneficially limit the offspring's postnatal weight gain during the first 4 months of life.

Docosahexaenoic Acid Supplementation in Lactating Women Increases Breast Milk and Erythrocyte Membrane Docosahexaenoic Acid Concentrations and Alters Infant n-6:n-3 Fatty Acid Ratio

Background

Low concentrations of docosahexaenoic acid (DHA) or high n-6 (ω-6):n-3 ratio in pregnant women is associated with poor fetal growth velocity and suboptimal neurodevelopment. However, there is a lack of data on levels of important n-6 and n-3 fatty acids (FAs) at different time points during pregnancy and lactation from India. Data on how much DHA is transferred during actual supplementation are also scarce.

Objectives

We report the concentrations of n-6 and n-3 FAs in maternal and infant blood and in breast milk following maternal supplementation with DHA or placebo.

Methods

A total of 957 pregnant women (≤20 wk) from Belagavi, Karnataka, were randomly assigned to receive either 400 mg/d of algal DHA or placebo through 6 mo postpartum. Blood samples were collected from the mother at recruitment/baseline, delivery, and 6 mo postpartum and from the infant at birth (cord) and 12 mo (venous). Breast milk samples were collected from a subsample at delivery, 1 mo and 6 mo postpartum. The FA profile was analyzed using gas chromatography.

Results

The concentration of DHA appeared to be higher in erythrocyte and breast milk samples of the DHA-supplemented group at all subsequent time points. The n-6:n-3 ratio was lower among women in the DHA group at delivery [DHA: 4.08 (1.79); placebo: 5.84 (3.57); P < 0.001] and at 6 mo postpartum [DHA: 5.34 (2.64); placebo: 7.69 (2.9); P < 0.001]. Infants of DHA-supplemented mothers also had a lower n-6:n-3 ratio at delivery and 12 mo. The n-6:n-3 ratio of breast milk increased from delivery through 1 to 6 mo but remained lower in the DHA-supplemented group than in the placebo.

Conclusions

Maternal DHA supplementation with 400 mg/d from early pregnancy through 6 mo postpartum significantly increased circulating DHA in breast milk and infant erythrocyte, whereas decreased erythrocyte and breast milk n-6:n-3 ratio. However, maternal supplementation did not get the ratio to the recommended levels.

Serum and diet long-chain omega-3 fatty acid nutritional status in Chinese elite athletes

Omega-3 polyunsaturated fatty acids (omega-3 PUFAs) are essential for improving the health and performance of athletes. The present study aimed to evaluate the nutritional status of omega-3 PUFAs in Chinese elite athletes by both dietary intake analysis and serum biomarker detection. A cross-sectional analysis of data from 54 elite athletes (24 men and 30 women) from Shanghai professional sports teams was conducted. A food frequency questionnaire (FFQ) was employed to analyze dietary intake, and gas chromatography-mass spectrometry (GC-MS/MS) was conducted to measure serum biomarkers of PUFAs. Correlation analysis was performed to investigate the relationships of PUFA biomarkers with diet, inflammation and oxidative stress. The results showed that the median intake of EPA + DHA among athletes was 132 mg/d, which is lower than the minimum value recommended by dietary guidelines (250 mg/d). The average serum EPA + DHA was 4.0 ± 1.1%, and the ratio of omega-6/omega-3 was 7.7 ± 1.7. Most (96.3%) of the athletes were below the targeted value of serum EPA + DHA, which is associated with a reduction in cardiovascular risk. Correlation analysis showed that the serum EPA + DHA was positively correlated with the long-term dietary intake of EPA + DHA and negatively correlated with inflammatory markers. In conclusion, the serum circulating EPA + DHA and omega-6/omega-3 ratio are effective biomarkers reflecting the nutritional status of PUFAs in athletes. Omega-3 PUFAs have a potential effect on inhibiting inflammatory markers. Hence, it is necessary for Chinese athletes to improve their suboptimal nutritional status of PUFAs through dietary intervention.

Complex Interactions Between Circulating Fatty Acid Levels, Desaturase Activities, and the Risk of Gestational Diabetes Mellitus: A Prospective Cohort Study

Objective

Maternal abnormal fatty acid desaturation has previously been linked to gestational diabetes mellitus (GDM). However, few studies have investigated this relationship longitudinally throughout pregnancy. In this study, we investigated the relationship between GDM and desaturase activities across the pregnancy trimesters.

Methods

A total of 661 women (GDM = 189, non-GDM = 472) were selected from the Complex Lipids in Mothers and Babies (CLIMB) cohort study. Clinical information and maternal serum were collected at 11–14, 22–28, and 32–34 weeks of gestation. Totally, 20 serum fatty acids were quantified using gas chromatography–mass spectrometry (GC-MS) analysis at each timepoint. Polyunsaturated fatty acid (PUFA) product-to-precursor ratios were used to estimate desaturase and elongase activities including delta-5 desaturase, delta-6 desaturase, stearoyl-CoA desaturase, and elongase.

Results

After adjusting for major potential confounders including maternal age, BMI, primiparity, smoking, and alcohol consumption, we observed a significant increase in the levels of γ-linolenic acid (GLA) and eicosatrienoic acid (DGLA) in the first trimester of women with GDM, whereas GLA and DGLA were reduced in the third trimester, when compared to the non-GDM group. Arachidonic acid (AA) showed an upward trend in the GDM group throughout pregnancy. Estimated delta-6 desaturase and delta-5 desaturase activity were elevated in the first trimester (OR = 1.40, 95% CI 1.03–1.91; OR = 0.56, 95% CI 0.32–0.96) but attenuated in the third trimester (OR = 0.78, 95% CI 0.58–1.07; OR = 2.64, 95% CI 1.46–4.78) in GDM pregnancies, respective to controls. Estimated delta-9–18 desaturase activity (OR = 3.70, 95% CI 1.49–9.19) was increased in women with GDM in later pregnancy.

Conclusions

Our study highlights the potential importance of fatty acid desaturase activities, particularly estimated delta-5 desaturase and delta-9–18 desaturase in the pathophysiology of GDM. These findings may have applications for the early diagnosis and management of GDM.

Maternal erythrocyte fatty acid composition as a predictive marker for pregnancy health

Pregnancy is accompanied by a surge in demand for fatty acids (FAs) in order to support maternal health, as well as fetal growth and development. Of particular demand is essential for long-chain polyunsaturated FAs. FAs are primarily obtained from dietary sources and are distributed in the body. In comparison with the use of self-reporting approaches, measuring the FA levels within different blood compartments can present a more accurate image of nutritional, and thus tissue, FA composition. Hence, the FA profile of plasma or serum is commonly used for physiological analyses. Nevertheless, plasma and serum FAs are not yet incorporated into cell membranes, and consequently may not be a suitable reflection of the FA status of body tissues. The evaluation of erythrocyte FA levels offers a superior possibility for the following reasons: the biological fluctuation of erythrocyte FA composition is low, phospholipids account for almost all the lipid content of erythrocytes, and the FA profiles of erythrocytes represent those of tissues. Here, we elaborate on whether the status of maternal erythrocyte FAs can serve as a prognostic biomarker for reproductive health and fetomaternal complications, including embryonic and fetoplacental development, gestational length, and preeclampsia. In addition, factors with the potential of altering the maternal erythrocyte FAs such as maternal diet, lifestyle habits, genetics, and body composition are discussed.

Plasma Fatty Acids, Not Dietary Fatty Acids, Associated with Obesity in Four Ethnic Minority Groups Unique to Southwest China: A Cross-Sectional Study

BACKGROUND

Dietary fatty acids (DFAs) and plasma fatty acids (PFAs) are linked to obesity. However, whether this association exists among ethnic minorities remains lacking. The present cross-sectional study was designed to investigate the correlation between DFAs, PFAs and obesity in four ethnic minority groups to Southwest China.

METHODS

A total of 166 obese people, and 166 normal-BMI subjects matched based on their age-, sex-, and ethnicity- were recruited from four different ethnic minority groups. DFAs were obtained through food frequency questionnaires. PFAs were assayed by GC/MS method. Binary and multiple regression analyses were performed to evaluate the correlation among DFAs, PFAs and obesity. Canonical correlation analysis (CCA) was conducted to assess the relationship between DFAs and PFAs.

RESULTS

FAs were found to be highest in the Naxi people and lowest in the Hani people. Multiple logistic regression analysis revealed that plasma C16:0 (OR = 1.310; 95% CI, 1.028-1.669) in the Hani people; plasma C20:3 n-6 (OR = 6.250; 95% CI, 1.224-31.927) and dietary C20:1 (OR = 9.231; 95% CI, 1.253-68.016) in the Wa people; plasma C18:0 (OR = 0.788; 95% CI, 0.681-0.912) in the Naxi people were seen to be independent predictive factors for obesity. CCA showed that DFAs were positively correlated with PFAs in the Naxi (r: 0.676; P < 0.05) and Bulang people (r: 0.897; P < 0.05), but there was no correlation in the Hani and Wa people.

CONCLUSION

In this study, PFAs but not DFAs were independently associated with obesity, and different among the four ethnic minorities.

Changes in fatty acid levels (saturated, monounsaturated and polyunsaturated) during pregnancy

BACKGROUND

During pregnancy a high amount of fatty acids (FA) is necessary to meet foetus demands, which vary during gestation. The present study describes the changes in maternal fatty acid concentrations during pregnancy in a sample of pregnant women.

METHODS

This is a longitudinal study of 479 pregnant women who were monitored from the first trimester to third trimester of pregnancy. Data on maternal characteristics were recorded and a serum sample was collected in each trimester. The fatty acid profile (saturated (SFA: total, lauric acid, myristic acid, palmitic acid, stearic acid), monounsaturated (MUFA: total, palmitoleic acid, oleic acid) and polyunsaturated fatty acids (PUFA: total omega-6 (n-6), linoleic acid, dihomo-γ-linolenic acid, arachidonic acid (AA), total omega-3 (n-3), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA)) was analysed with a gas chromatography-mass spectrometry combination.

RESULTS

From the first trimester to third trimester of pregnancy, a significant increase in total SFA, total MUFA and total n-6 PUFA was found. (p < 0.001). Nevertheless, the serum concentration of arachidonic acid (AA), eicosapentaenoic acid (EPA) and total n-3 PUFA decreased during gestation (p < 0.001). A statistically non-significant result was observed for the docosahexaenoic acid (DHA) serum concentration between the first and third trimesters of pregnancy. Significant correlations were observed between each total fatty acid concentrations of the first and third trimesters.

CONCLUSION

The circulating serum concentration of SFA, MUFA and n-6 PUFA increases during pregnancy, whereas essential fatty acids such as AA and EPA decrease, and DHA remains unchanged. Further research is necessary to understand the role played by FA throughout gestation.

Maternal DHA Supplementation during Pregnancy and Lactation in the Rat Protects the Offspring against High-Calorie Diet-Induced Hepatic Steatosis

Maternal supplementation during pregnancy with docosahexaenoic acid (DHA) is internationally recommended to avoid postpartum maternal depression in the mother and improve cognitive and neurological outcomes in the offspring. This study was aimed at determining whether this nutritional intervention, in the rat, protects the offspring against the development of obesity and its associated metabolic disorders. Pregnant Wistar rats received an extract of fish oil enriched in DHA or saline (SAL) as placebo by mouth from the beginning of gestation to the end of lactation. At weaning, pups were fed standard chow or a free-choice, high-fat, high-sugar (fc-HFHS) diet. Compared to animals fed standard chow, rats exposed to the fc-HFHS diet exhibited increased body weight, liver weight, body fat and leptin in serum independently of saline or DHA maternal supplementation. Nevertheless, maternal DHA supplementation prevented both the glucose intolerance and the rise in serum insulin resulting from consumption of the fc-HFHS diet. In addition, animals from the DHA-fc-HFHS diet group showed decreased hepatic triglyceride accumulation compared to SAL-fc-HFHS rats. The beneficial effects on glucose homeostasis declined with age in male rats. Yet, the preventive action against hepatic steatosis was still present in 6-month-old animals of both sexes and was associated with decreased hepatic expression of lipogenic genes. The results of the present work show that maternal DHA supplementation during pregnancy programs a healthy phenotype into the offspring that was protective against the deleterious effects of an obesogenic diet.

Maternal Metabolic Biomarkers are Associated with Obesity and Excess Gestational Weight Gain

OBJECTIVE

The purpose of this study was to evaluate the independent contribution of maternal obesity and gestational weight gain (GWG) in excess of the Institute of Medicine's guidelines on levels of maternal serum inflammatory and metabolic measures.

STUDY DESIGN

Banked maternal serum samples from 120 subjects with documented prepregnancy or first trimester body mass index (BMI) were utilized for analyte analyses. Validated, BMI-specific formulas were utilized to categorize GWG as either insufficient, at goal or excess based on the Institute of Medicine guidelines with gestational age adjustments. Serum was analyzed for known inflammatory or metabolic pathway intermediates using the Luminex xMap system with the MILLIPLEX Human Metabolic Hormone Magnetic Bead Panel. Measured analytes included interleukin-6, monocyte chemoattractant protein-1, and tumor necrosis factor-α and metabolic markers amylin, c-peptide, ghrelin, gastric inhibitory polypeptide, glucagon-like peptide-1, glucagon, insulin, leptin, pancreatic polypeptide, and peptide YY. Kruskal-Wallis ANOVA and Pearson's correlation coefficients were calculated for each marker.

RESULTS

C-peptide, insulin, and leptin all varied significantly with both obesity and GWG while glucagon-like peptide-1 varied by BMI but not GWG. These analytes covaried with other metabolic analytes, but not with inflammatory analytes.

CONCLUSION

Maternal metabolic biomarkers at delivery vary significantly with both obesity and GWG. Taken together, these findings suggest that GWG (with and without comorbid obesity) is an important mediator of measurable metabolites in pregnancy but is not necessarily accompanied by inflammatory measures in serum. These findings are consistent with GWG being an independent risk factor for metabolic disturbances during pregnancy.

Long-chain polyunsaturated fatty acid (LC-PUFA) status in severe preeclampsia and preterm birth: a cross sectional study

Long-Chain Polyunsaturated Fatty Acid (LCPUFA) is essential throughout pregnancy, since deficiency of LPUFA may linked to obstetrical complications. This study aimed to investigate LCPUFA status in severe preeclampsia and preterm birth. A cross sectional study was conducted in 104 pregnant women, which divided into normal pregnancy, severe preeclampsia and preterm birth groups. Serum percentage and concentration of total LCPUFA, omega-3, alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), omega-6, linoleic acid (LA), and arachidonic acid (AA) were measured using gas chromatography/mass spectrometry. Receiver operating characteristic (ROC), bivariate and multivariate analysis were performed. Severe preeclampsia showed the highest concentration of total PUFA and the lowest DHA percentage, with significantly higher Omega-6/Omega-3 ratio (p = 0.004) and lower omega-3 index (p < 0.002) compared to control. Preterm birth showed the least omega-3 concentrations, with significantly low omega-6 derivates (LA (p = 0.014) and AA (p = 0.025)) compared to control. LCPUFA parameters have shown to increase the risk in both conditions, particularly ALA ≤ 53 µmol/L in preeclampsia with OR 5.44, 95%CI 1.16-25.42 and preterm birth with OR 4.68, 95%CI 1.52-14.38. These findings suggest that severe preeclampsia and preterm birth have an imbalance in LCPUFA status.

Impact of Maternal Obesity on the Metabolism and Bioavailability of Polyunsaturated Fatty Acids during Pregnancy and Breastfeeding

Prenatal and postnatal development are closely related to healthy maternal conditions that allow for the provision of all nutritional requirements to the offspring. In this regard, an appropriate supply of fatty acids (FA), mainly n-3 and n-6 long-chain polyunsaturated fatty acids (LCPUFA), is crucial to ensure a normal development, because they are an integral part of cell membranes and participate in the synthesis of bioactive molecules that regulate multiple signaling pathways. On the other hand, maternal obesity and excessive gestational weight gain affect FA supply to the fetus and neonate, altering placental nutrient transfer, as well as the production and composition of breast milk during lactation. In this regard, maternal obesity modifies FA profile, resulting in low n-3 and elevated n-6 PUFA levels in maternal and fetal circulation during pregnancy, as well as in breast milk during lactation. These modifications are associated with a pro-inflammatory state and oxidative stress with short and long-term consequences in different organs of the fetus and neonate, including in the liver, brain, skeletal muscle, and adipose tissue. Altogether, these changes confer to the offspring a higher risk of developing obesity and its complications, as well as neuropsychiatric disorders, asthma, and cancer. Considering the consequences of an abnormal FA supply to offspring induced by maternal obesity, we aimed to review the effects of obesity on the metabolism and bioavailability of FA during pregnancy and breastfeeding, with an emphasis on LCPUFA homeostasis.

In pregnancy, maternal HDL is specifically enriched in, and carries the highest proportion of, DHA in plasma

Arachidonic acid (AA) and docosahexaenoic acid (DHA) are important for neurological development. The aim was to determine the distribution and relative enrichment of AA and DHA among lipoprotein fractions prior to pregnancy, throughout gestation and in the post-partum period. Our hypothesis was that in pregnancy, in contrast to the non-pregnant state, AA and DHA are carried in highest concentration in the very low density lipoprotein (VLDL) fraction secondary to increased gestational liver triglyceride secretion. Two independent prospective, observational cohort studies carried out in Glasgow were combined; one early in pregnancy and one later in pregnancy with post-partum follow up. Across the pregnancy timeline plasma lipoproteins were isolated using sequential ultracentrifugation and lipoprotein fatty acids were extracted and analysed by gas chromatography. High density lipoprotein (HDL) had the highest concentration of AA and DHA compared to other lipoproteins. HDL became progressively enriched in the proportion of triglycerides at 16 weeks of gestation, which peaked at 35 weeks and returned to baseline at 13 weeks postpartum. HDL DHA per HDL-cholesterol and HDL DHA per apoA-I became progressively enriched at 16 weeks of gestation, peaked at 25 weeks and returned to baseline at 13 weeks postpartum, whereas HDL AA (per HDL-C or HDL-apoA-I) did not differ. DHA is carried primarily in HDL rather than VLDL. HDL has anti-oxidant properties that might afford DHA protection against oxidation.

Five serum fatty acids are associated with subclinical hypothyroidism in a Chinese pregnant population

Subclinical hypothyroidism (SCH) is a common endocrine disorder affecting women of reproductive age. Although SCH and abnormal fatty acid composition are often associated with adverse pregnancy outcomes and metabolic syndrome later in maternal and fetal life, the longitudinal relationship between SCH and serum fatty acids during pregnancy has rarely been studied. Therefore, the aim of this study was to investigate the association between SCH and maternal serum fatty acids throughout gestation. A total of 240 women enrolled in the Complex Lipids in Mothers and Babies (CLIMB) study in Chongqing, China were included in our study. Clinical information and maternal serum samples were collected at three time points during pregnancy: 11-14th, 22-28th, and 32-34th weeks of gestation. Twenty serum fatty acids were quantified using gas chromatography-mass spectrometry (GC-MS) analysis. A majority of the 20 serum fatty acids increased as gestation progressed in women with a normal pregnancy and women experiencing SCH. Levels of arachidic acid, docosahexaenoic acid, and eicosenoic acid were significantly higher in the serum of women with SCH when compared to women with a normal pregnancy, in the second trimester. On the other hand, the levels of eicosadienoic acid and octadecanoic acid were significantly higher in SCH in the third trimester. Our findings demonstrate that serum fatty acid composition during the second and third trimesters was significantly associated with SCH in pregnant Chinese women.

Maternal Adipose Tissue Expansion, A Missing Link in the Prediction of Birth Weight Centile

CONTEXT

Maternal body mass index (BMI) is associated with increased birth weight but does not explain all the variance in fetal adiposity.

OBJECTIVE

To assess the contribution of maternal body fat distribution to offspring birth weight and adiposity.

DESIGN

Longitudinal study throughout gestation and at delivery.

SETTING

Women recruited at 12 weeks of gestation and followed up at 26 and 36 weeks. Cord blood was collected at delivery.

PATIENTS

Pregnant women (n = 45) with BMI 18.0 to 46.3 kg/m2 and healthy pregnancy outcome.

METHODS

Maternal first trimester abdominal subcutaneous and visceral adipose tissue thickness (SAT and VAT) was assessed by ultrasound.

MAIN OUTCOME MEASURES

Maternal body fat distribution, maternal and cord plasma glucose and lipid concentrations, placental weight, birth weight, and fetal adiposity assessed by cord blood leptin.

RESULTS

VAT was the only anthropometric measure independently associated with birth weight centile (r2 adjusted 15.8%, P = .002). BMI was associated with trimester 2 and trimesters 1 through 3 area under the curve (AUC) glucose and insulin resistance (Homeostatic Model Assessment). SAT alone predicted trimester 2 lipoprotein lipase (LPL) mass (a marker of adipocyte insulin sensitivity) (11.3%, P = .017). VAT was associated with fetal triglyceride (9.3%, P = .047). Placental weight was the only independent predictor of fetal adiposity (48%, P < .001). Maternal trimester 2 and AUC LPL were inversely associated with fetal adiposity (r = -0.69, P = .001 and r = -0.58, P = .006, respectively).

CONCLUSIONS

Maternal VAT provides additional information to BMI for prediction of birth weight. VAT may be a marker of reduced SAT expansion and increased availability of maternal fatty acids for placental transport.

Influence of clinical characteristics on maternal DHA and other polyunsaturated fatty acid status in pregnancy: A systematic review

INTRODUCTION

Omega-3 DHA is important for the prevention of preterm birth, however there is limited knowledge of the determinants of omega-3 status during pregnancy. The primary objective of this systematic review was to synthesise data from existing studies assessing relationships between clinical factors and maternal DHA status.

MATERIALS AND METHODS

The Medline, Embase, Amed, and CINAHL databases were searched for studies reporting measures of maternal omega-3 status and one or more clinical characteristics.

RESULTS

Eighteen studies were included in the final analyses. Factors associated with a higher BMI (overweight, higher gestational weight gain, gestational diabetes), or lower parity were each associated with higher omega-3 status in the majority of studies, with mixed findings for other comparisons.

DISCUSSION

Inconsistent findings between studies make it difficult to draw clear conclusions about the relationship between clinical factors and maternal omega-3 DHA status. However, maternal overweight and associated metabolic conditions may increase lipid metabolism.

A High-Throughput Method for the Analysis of Erythrocyte Fatty Acids and the Omega-3 Index

Omega-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) have several health benefits. In particular, low n-3 LCPUFA status is associated with cardiovascular disease (CVD) and led to the development of the omega-3 index that is the proportion of eicosapentaenoic acid and docosahexaenoic acid in the erythrocyte membranes, as a marker of CVD risk. Most methods used to measure the omega-3 index are laborious and time consuming. Therefore, the aim of this study was to develop a high-throughput method for the extraction and measurement of erythrocyte fatty acids and the omega-3 index. For sample extraction and quantification, two methods were used; a single-step extraction, degradation, and derivatization method by Lepage and Roy, followed by gas chromatography flame ionization detection (GC-FID), which is commonly used and a high-throughput method using an automated methyl tert-butyl ether extraction followed by electrospray ionization mass spectrometry. Both methods were first applied to the analysis of known concentrations of synthetic phospholipid (PL) mixtures to determine recovery and precision prior to their application in the analysis of human erythrocytes. The range of recoveries over five synthetic PL mixtures were 86.4-108.9% and the coefficient of variation was <10% (within-run) and ≤15.2% (between-run). Both methods showed high correlation (R = 0.993) for the omega-3 index and there was no systematic bias in the detection of omega-3 index using either method. The new high-throughput method described here offers considerable advantages in terms of simplicity and throughput compared to the GC-FID method and provides additional information on molecular PL concentrations.

Relationships between docosahexaenoic acid compositions of maternal and umbilical cord erythrocytes in pregnant Japanese women

Previous reports have shown that the transfer of docosahexaenoic acid (DHA) from mother to fetus during pregnancy is important for development of the child's nervous and visual functions. The amount of DHA passing through the placenta varies depending on the relative DHA compositions of the erythrocytes in the maternal blood and the umbilical cord. Prior research has reported that if the DHA composition of the maternal erythrocytes is over 5.6 g%, DHA in the erythrocytes of the child undergoes bioattenuation, whereas it undergoes biomagnification if the maternal erythrocyte composition is lower than 5.6 g%. The relationship between DHA levels in maternal erythrocytes during pregnancy and in umbilical cord erythrocytes at delivery was assessed in Japanese pregnant women. This study was performed as an adjunct study of the Japan Environment and Children's Study. DHA compositions of maternal erythrocytes at 24-30 weeks of pregnancy and of umbilical cord erythrocytes at delivery were determined in 1368 mother-infant pairs. Median DHA values were 7.41% in the maternal erythrocytes and 6.84% in the umbilical cord erythrocytes, indicating significantly lower levels in the umbilical cord. When DHA composition in maternal erythrocytes was lower than 6.6%, DHA was theoretically higher in umbilical cord erythrocytes than in maternal erythrocytes. Conversely, when DHA composition in maternal erythrocytes was higher than 6.6%, DHA in umbilical cord erythrocytes was theoretically lower than in maternal erythrocytes. We therefore consider that there is a turning point of around 6% in the DHA composition of maternal and umbilical cord blood that is exchanged between mother and fetus: if the composition in the maternal blood is higher, then bioattenuation in DHA transfer from the maternal circulation to the umbilical cord occurs, while if it is lower, then biomagnification occurs. This corroborates the findings of previous research.

Non-dietary factors associated with n-3 long-chain PUFA levels in humans - a systematic literature review

Numerous health benefits are attributed to the n-3 long-chain PUFA (n-3 LCPUFA); EPA and DHA. A systematic literature review was conducted to investigate factors, other than diet, that are associated with the n-3 LCPUFA levels. The inclusion criteria were papers written in English, carried out in adult non-pregnant humans, n-3 LCPUFA measured in blood or tissue, data from cross-sectional studies, or baseline data from intervention studies. The search revealed 5076 unique articles of which seventy were included in the qualitative synthesis. Three main groups of factors potentially associated with n-3 LCPUFA levels were identified: (1) unmodifiable factors (sex, genetics, age), (2) modifiable factors (body size, physical activity, alcohol, smoking) and (3) bioavailability factors (chemically bound form of supplements, krill oil v. fish oil, and conversion of plant-derived α-linolenic acid (ALA) to n-3 LCPUFA). Results showed that factors positively associated with n-3 LCPUFA levels were age, female sex (women younger than 50 years), wine consumption and the TAG form. Factors negatively associated with n-3 LCPUFA levels were genetics, BMI (if erythrocyte EPA and DHA levels are &lt;5·6 %) and smoking. The evidence for girth, physical activity and krill oil v. fish oil associated with n-3 LCPUFA levels is inconclusive. There is also evidence that higher ALA consumption leads to increased levels of EPA but not DHA. In conclusion, sex, age, BMI, alcohol consumption, smoking and the form of n-3 LCPUFA are all factors that need to be taken into account in n-3 LCPUFA research.

Exposure to a Farm Environment During Pregnancy Increases the Proportion of Arachidonic Acid in the Cord Sera of Offspring

Growing up in a farm environment is protective against allergy development. Various explanations have been put forward to explain this association. Fatty acids are regulators of immune function and the composition of fatty acids in the circulation system may affect immune development. Here, we investigate whether the fatty acid composition of cord serum differs for infants born to Farm (n = 26) or non-Farm mothers (n =29) in the FARMFLORA birth-cohort. For comparison, the levels of fatty acids in the maternal diet, serum and breast milk around 1 month post-partum were recorded. The fatty acids in the cord sera from infants born to Farm mothers had higher proportions of arachidonic acid (20:4 n-6) and adrenic acid (22:4 n-6) than those from infants born to non-Farm mothers. No differences were found for either arachidonic acid or adrenic acid in the diet, samples of the serum, or breast milk from Farm and non-Farm mothers obtained around 1 month post-partum. The arachidonic and adrenic acid levels in the cord blood were unrelated to allergy outcome for the infants. The results suggest that a farm environment may be associated with the fatty acid composition to which the fetus is exposed during pregnancy.

Dietary ALA, EPA and DHA have distinct effects on oxylipin profiles in female and male rat kidney, liver and serum

There is much data on the effects of dietary n-3 fatty acids on tissue fatty acid compositions, but comparable comprehensive data on their oxygenated metabolites (oxylipins) is limited. The effects of providing female and male rats with diets high in α-linolenic acid (ALA), EPA or DHA for 6 weeks on oxylipins and fatty acids in kidney, liver and serum were therefore examined. The oxylipin profile generally reflected fatty acids, but it also revealed unique effects of individual n-3 fatty acids that were not apparent from fatty acid data alone. Dietary ALA increased renal and serum DHA oxylipins even though DHA itself did not increase, while dietary EPA did not increase DHA oxylipins in kidney or liver, suggesting that high EPA may inhibit this conversion. Oxylipin data generally corroborated fatty acid data that indicated that DHA can be retroconverted to EPA and that further retroconversion to ALA is limited. Dietary n-3 fatty acids decreased n-6 fatty acids and their oxylipins (except linoleic acid and its oxylipins), in order of effectiveness of DHA > EPA > ALA, with some exceptions: several arachidonic acid oxylipins modified at carbon 15 were not lower in all three sites, and EPA had a greater effect on 12-hydroxy-eicosatetraenoic acid and its metabolites in the liver. Oxylipins were predominantly higher in males, which was not reflective of fatty acids. Tissue-specific oxylipin profiles, therefore, provide further information on individual dietary n-3 fatty acid and sex effects that may help explain their unique physiological effects and have implications for dietary recommendations.

Low omega-3 index values and monounsaturated fatty acid levels in early pregnancy: an analysis of maternal erythrocytes fatty acids

Background

It is unanimously recognized that the maternal nutritional status at the pregnancy onset influence both short-term and long-term health of the mother and offspring. Among several nutrients, LCPUFA, particularly from the omega-3 family, are of utmost importance. This study was carried out to determine fatty acids profile of maternal erythrocyte membranes in early pregnancy and to identify potential determinants impacting on this status.

Methods

A cohort of 122 healthy women with a singleton pregnancy was included. Fatty acids were analyzed using gas chromatography. Because of the lack of cutoff values, reference ranges were used to determine fatty acids categories.

Results

Of concern, our data revealed low monounsaturated and long-chain omega-3 fatty acid status in most participants. More than 75% of Belgian pregnant women exhibited Pal, AO and EPA levels as well as IOM3 values below the laboratory reference ranges. Higher DHA concentrations and IOM3 values were found among foreign-nationality participants, non-smokers and physically active women. With regard to dietary factors, omega-3 supplements and diet seem to be complementary since DHA from supplements (but not from diet) and EPA from diet (but not from supplements) were found to be associated with higher concentrations of DHA and EPA, respectively.

Conclusions

Our study presents evidence demonstrating that the fatty acid status of most early pregnant women is far from being optimal based on the admitted general reference values. Clinicians should be advice to carefully evaluate and improve this status to guarantee the best possible outcome for both the mother and the baby.

Electronic supplementary material

The online version of this article (10.1186/s12944-018-0716-6) contains supplementary material, which is available to authorized users.

Pre-conception maternal erythrocyte saturated to unsaturated fatty acid ratio predicts pregnancy after natural cycle frozen embryo transfer

The environment for embryo implantation and fetal growth and development is affected by maternal nutritional, metabolic and health status. The aim of this prospective, cohort study was to test whether plasma metabolic and inflammatory biomarkers can predict pregnancy resulting from in vitro fertilisation (IVF). Women with a natural menstrual cycle undergoing frozen embryo transfer (FET) were recruited and fasting baseline blood samples were collected a mean of 3.4 days prior to the luteinising hormone (LH) surge and a non-fasting blood sample was taken on the day of FET. Ongoing pregnancy was defined by positive fetal heartbeat on ultrasound scan at day 45 post LH surge. Thirty-six pregnancies resulted from FET in 143 women. In an overall stepwise multivariable analysis, erythrocyte saturated to unsaturated fatty acid ratio was positively associated with ongoing pregnancy. A similar model incorporating day of FET covariates found that erythrocyte saturated to unsaturated fatty acid ratio, erythrocyte fatty acid average chain length and plasma log-triglycerides predicted ongoing pregnancy. In conclusion, a higher peri-conceptional saturated to unsaturated fatty acid ratio predicted ongoing pregnancy after natural cycle frozen embryo transfer and may reflect a maternal nutritional status that facilitates pregnancy success in this assisted conception scenario.

DHA supplementation during pregnancy as phospholipids or TAG produces different placental uptake but similar fetal brain accretion in neonatal piglets

The great variety of n-3 long-chain PUFA sources raises the question of the most adequate for using as a DHA supplement during pregnancy. Placental and fetal availability of different DHA sources remains unclear. We investigated DHA availability in maternal lipoproteins, placenta and fetal tissues in pregnant sows fed DHA as phospholipid (PL) or TAG to identify the best DHA source during this period. Pregnant Iberian sows were fed diets containing 0·8 % DHA of total fatty acids as PL from egg yolk or TAG from algae oil during the last third of gestation (40 d). Maternal tissues, placentas and fetal tissues were obtained at delivery and DHA quantified by GC. Major Facilitator Superfamily Domain Containing 2a (MFSD2a) carrier expression was analysed in both placenta and fetal brain by Western blotting. Sows fed the DHA–PL diet showed higher DHA incorporation in plasma LDL but not in plasma total lipids. No differences were found in DHA content between groups in maternal liver, adipose tissue or brain. Placental tissue incorporated more DHA in both total lipids and PL fraction in sows fed DHA–PL. However, this did not lead to an enhanced DHA accretion either in fetal plasma, fetal liver or fetal brain. MFSD2a expression was similar between both experimental groups. Maternal DHA supplementation during pregnancy in sow either as PL or TAG produces similar DHA accretion in fetal tissues but not in placenta. Both fat sources are equally available for fetal brain.

Relationship between Changes in Fatty Acid Composition of the Erythrocyte Membranes and Fatty Acid Intake during Pregnancy in Pregnant Japanese Women

OBJECTIVE

Docosahexaenoic acid (DHA) is an important nutrient required by pregnant women and fetuses. Several studies suggest that fatty acid composition changes during pregnancy. However, the association of longitudinal changes in erythrocyte fatty acid composition and dietary fatty acid intake during pregnancy is not well understood. We assessed the relationship between fatty acid composition of the erythrocyte membranes and fatty acid intake at each trimester in pregnant Japanese women.

METHODS

We conducted a prospective hospital-based cohort study. We investigated fatty acid composition of the erythrocyte membranes and intake of fatty acids during the three trimesters in 178 healthy, pregnant Japanese women.

RESULTS

The eicosapentaenoic acid and arachidonic acid percentage of the erythrocyte membranes significantly decreased. The percentages of linoleic acid and α-linolenic acid significantly increased during pregnancy. The DHA percentage in the erythrocyte membranes decreased from the second to the third trimester. The DHA percentage in the erythrocyte membranes positively correlated with DHA intake in the third trimester.

CONCLUSION

In pregnant Japanese women, the fatty acid composition of the erythrocyte membranes markedly changed throughout pregnancy. The DHA intake in the third trimester may be insufficient to maintain DHA percentage in the maternal erythrocyte membranes.

Serum n-3 polyunsaturated fatty acids are inversely associated with longitudinal changes in depressive symptoms during pregnancy

BACKGROUNDS

N-3 polyunsaturated fatty acids (PUFAs) have been hypothesised to be protective for depression during pregnancy. However, there are few data and no consensus regarding this association. In this line, we aim to evaluate if the concentration of n-3 and n-6 PUFAs, and their ratio, are associated with depressive symptoms throughout pregnancy.

METHOD

A prospective cohort of 172 Brazilian women was followed at 5-13th, 20-26th and 30-36th weeks of gestation. The presence of depressive symptoms was evaluated using the Edinburgh Postnatal Depression Scale (EPDS) at each pregnancy trimester. Depression was defined as an EPDS score ≥11. The concentrations of n-3 [α-linolenic acid; eicosapentaenoic acid (EPA); docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA)] and n-6 PUFAs [linoleic acid; γ linolenic acid; eicosadienoic acid; eicosatrienoic acid; arachidonic acid; docosatetraenoic acid and docosapentaenoic acid] were expressed as absolute (μg/ml) values. The total n-6/n-3 ratio was calculated. Statistical analyses were performed using univariate and adjusted random intercept logistic model for each fatty acid (FA) considering the longitudinal nature of data. Covariates were selected as potential confounders based on their biological plausibility of having an association with the concentration of FA and depressive symptoms during pregnancy.

RESULTS

The prevalence of depressive symptoms was high in all pregnancy trimesters (1st = 33.7%; 2nd = 18.9%; 3rd = 17.4%). We did not find differences in means FA concentrations by depressive symptom classification, for each follow-up visit. The women presented a 5% decrease in the odds of having depressive symptoms for each one-week increase in the gestational age. As individual women progressed through pregnancy, higher concentrations of EPA (odds ratio (OR) = 0.92; 95% CI: 0.86-0.99), DHA (OR = 0.96; 95% CI: 0.93-0.99), DPA (OR = 0.87; 95% CI: 0.77-0.99) and total n-3 (OR = 0.98; 95% CI: 0.96-0.99) were associated with a lower odds of depressive symptoms, while higher total n-6/n-3 ratio were associated with greater odds of depressive symptoms (OR = 1.40; 95% CI: 1.09-1.79). We detected a decrease in the probability of depressive symptoms as concentrations of total n-3 FA, α-linolenic acid, DPA, and DHA increased. We also observed a sharper decline for women with initial greater chance of depressive symptoms compared with those with lower chance of having these symptoms.

CONCLUSIONS

We found a high prevalence of depressive symptoms in low-income Brazilian pregnant women and no significant associations between n-6 FA and depressive symptoms. Lower serum concentrations of DHA, EPA and DPA and a higher n-6/n-3 ratio at each pregnancy trimester were associated with higher odds of depressive symptoms throughout pregnancy.

Polyunsaturated Fatty Acid Levels in Maternal Erythrocytes of Japanese Women during Pregnancy and after Childbirth

Background: The transport of polyunsaturated fatty acids (PUFAs), such as arachidonic acid (ARA, 20:4n-6) and docosahexaenoic acid (DHA, 22:6n-3), to the fetus from maternal stores increases depending on the fetal requirements for PUFA during the last trimester of pregnancy. Therefore, maternal blood PUFA changes physiologically with gestational age. However, the changes in PUFA levels in maternal blood erythrocytes during pregnancy and after childbirth have not been fully investigated in a fish-eating population. Objective: To examine the changes of ARA and DHA levels in maternal erythrocytes with the progress of pregnancy and the relationship between maternal and umbilical cord erythrocyte PUFA levels in pregnant Japanese women who habitually eat fish and shellfish. Design: This study was performed as a part of the adjunct study of the Japan Environment and Children’s Study (JECS). The participants were 74 pregnant women. The maternal blood samples were collected at 27, 30, and 36 weeks of pregnancy, and 2 days and 1 month after delivery, and umbilical cord blood was collected at delivery. The fatty acid levels of erythrocytes in these blood samples were determined. Results: ARA and DHA levels in maternal erythrocytes tended to decrease with the progress of pregnancy. While the DHA level decreased further after delivery, the ARA level returned to the value at 27 weeks of pregnancy within 1 month after delivery. The n-3 and n-6 PUFA levels in maternal erythrocytes at 27, 30, and 36 weeks of pregnancy were significantly positively correlated with the corresponding fatty acid levels in umbilical cord erythrocytes. Conclusion: The present findings showed a significant change in erythrocyte PUFA levels during pregnancy and after childbirth in a fish-eating population. The PUFA levels of maternal blood after the second trimester may be a reliable marker for predicting PUFA levels in infants’ circulating blood.

Both maternal and offspring Elovl2 genotypes determine systemic DHA levels in perinatal mice

The molecular details relevant to dietary supplementation of the omega-3 fatty acid DHA in mothers as well as in their offspring are not clear. The PUFA elongase, elongation of very long-chain fatty acid (ELOVL)2, is a critical enzyme in the formation of DHA in mammals. In order to address the question regarding the origin of DHA during perinatal life, we have used DHA-deficient Elovl2-ablated mice as a model system to analyze the maternal impact on the DHA level in their offspring of various genotypes. Elovl2^-/- mothers maintained on control diet had significantly lower systemic levels of DHA compared with the Elovl2^+/- and Elovl2^+/+ mothers. Dietary DHA administration during the pregnancy and lactation periods led to increased DHA accretion in maternal tissues and serum of all genotypes. The proportion of DHA in the liver and serum of the Elovl2^-/- offspring was significantly lower than in the Elovl2^+/+ offspring. Remarkably, the DHA level in the Elovl2^+/- offspring nursed by DHA-free-fed Elovl2^-/- mothers was almost as high as in +/+ pups delivered by +/+ mothers, suggesting that endogenous synthesis in the offspring can compensate for maternal DHA deficiency. Maternal DHA supplementation had a strong impact on offspring hepatic gene expression, especially of the fatty acid transporter, Mfsd2a, suggesting a dynamic interplay between DHA synthesis and DHA uptake in the control of systemic levels in the offspring.

Maternal Plasma DHA Levels Increase Prior to 29 Days Post-LH Surge in Women Undergoing Frozen Embryo Transfer: A Prospective, Observational Study of Human Pregnancy

CONTEXT

Docosahexaenoic acid (DHA) is an important fatty acid required for neurological development but its importance during early fetal neurological organogenesis is unknown.

OBJECTIVE

This study aimed to assess plasma fatty acid changes in early pregnancy in women undergoing natural cycle-frozen embryo transfer as a means of achieving accurately timed periconceptual sampling.

DESIGN

Women undergoing frozen embryo transfer were recruited and serial fasting blood samples were taken pre-luteinizing hormone (LH) surge, and at 18, 29, and 45 d post-LH surge and fatty acids were analyzed using gas chromatography.

SETTING

This study took place at the Assisted Conception Unit, Glasgow Royal Infirmary, Scotland.

MAIN OUTCOME MEASURES

Plasma fatty acid concentrations and influence of twin pregnancies on DHA plasma concentration were measured.

RESULTS

In pregnant women, there was a rapid, early increase in the maternal rate of change of plasma DHA concentration observed by 29 d post-LH surge (mean ± SD, from 0.1 ± 1.3 to 1.6 ± 2.9 nmol DHA per mL plasma per day). This early pressure to increase plasma DHA concentration was further emphasized in twin pregnancies where the increase in DHA concentration over 45 d was 2-fold higher than in singleton pregnancies (mean ± SD increase, 74 ± 39 nmol/mL vs 36 ± 40 nmol/mL). An index of delta-6 desaturase activity increased 30% and positively correlated with the rate of change of DHA concentration between 18 and 29 d post-LH surge (R2 adjusted = 41%; P = .0002). DHA was the only fatty acid with a continual accelerated increase in plasma concentration and a positive incremental area under the curve (mean ± SD, 632 ± 911 nmol/mL × d) during the first 45 d of gestation.

CONCLUSIONS

An increase in maternal plasma DHA concentration is initiated in human pregnancy prior to neural tube closure which occurs at 28 d gestation.

DHA in Pregnant and Lactating Women from Coastland, Lakeland, and Inland Areas of China: Results of a DHA Evaluation in Women (DEW) Study

Few studies have examined docosahexaenoic acid (DHA) in pregnant and lactating women in developing countries like China, where DHA-enriched supplements are increasingly popular. We aimed to assess the DHA status among Chinese pregnant and lactating women residing areas differing in the availability of aquatic products. In total, 1211 women in mid-pregnancy (17 ± 2 weeks), late pregnancy (39 ± 2 weeks), or lactation (42 ± 7 days) were enrolled from Weihai (coastland), Yueyang (lakeland), and Baotou (inland) city, with approximately 135 women in each participant group by region. DHA concentrations were measured using capillary gas chromatography, and are reported as weight percent of total fatty acids. Mean plasma DHA concentrations were higher in coastland (mid-pregnancy 3.19%, late pregnancy 2.54%, lactation 2.24%) and lakeland women (2.45%, 1.95%, 2.26%) than inland women (2.25%, 1.67%, 1.68%) (p values < 0.001). Similar differences were observed for erythrocyte DHA. We conclude that DHA concentrations of Chinese pregnant and lactating women are higher in coastland and lakeland regions than in inland areas. DHA status in the study population appears to be stronger than populations from other countries studied to date.

Lower inter-partum interval and unhealthy life-style factors are inversely associated with n-3 essential fatty acids changes during pregnancy: a prospective cohort with Brazilian women

OBJECTIVE

To analyze serum fatty acids concentrations during healthy pregnancy and evaluate whether socioeconomic, demographic, obstetric, nutritional, anthropometric and lifestyle factors are associated with their longitudinal changes.

STUDY DESIGN

A prospective cohort of 225 pregnant women was followed in the 5th-13th, 20th-26th and 30th-36th weeks of gestation. Serum samples were collected in each trimester of pregnancy and analyzed to determine the fatty acids composition using a high-throughput robotic direct methylation method coupled with fast gas-liquid chromatography. The independent variables comprised the subjects' socioeconomic and demographic status, obstetric history, early pregnancy body mass index (BMI), dietary and lifestyle parameters. Analyses were performed using linear mixed-effects models.

RESULTS

The overall absolute concentrations of fatty acids increased from the 1st to the 2nd trimester and slightly increased from the 2nd to the 3rd trimester. Early pregnancy BMI, inter-partum interval and weekly fish intake were the factors associated with changes in eicosapentaenoic + docosahexaenoic acids (EPA+DHA) and total n-3 polyunsaturated fatty acids (PUFAs). Early pregnancy BMI, age and monthly per-capita income were inversely associated with the changes in the n-6/n-3 ratio. Alcohol consumption was positively associated with the n-6/n-3 ratio.

CONCLUSION

Early pregnancy BMI was positively associated with EPA+DHA and total n-3 PUFAs, while presenting a reduced weekly fish intake and a lower inter-partum interval were associated with lower levels of n-3 PUFAs. A lower per-capita family income and a drinking habit were factors that were positively associated with a higher n-6/n-3 ratio.

Treatment of ovariectomized rats with 17β-estradiol increases hepatic delta-6 desaturase enzyme expression and docosahexaenoic acid levels in hepatic and plasma phospholipids

Higher docosahexaenoic acid (DHA) in females compared with males suggests ovarian hormones increase DHA production. Eight-week old rats were ovariectomized or sham operated (SHAM), and ovariectomized rats were treated with implanted pellets providing 17β-estradiol (OVX+E), progesterone (OVX+P), both (OVX+PE) or neither (OVX) for 14 days. Immunoblot and fatty acid analysis were performed on all samples, and microarray analysis was performed on OVX and SHAM groups. Increased Δ6-desaturase in OVX relative to SHAM was observed by microarray (12% higher) and immunoblot (31% higher). OVX+E and OVX+PE rats had 39% and 42% higher Δ6-desaturase content, respectively, compared with OVX. OVX+E and OVX+PE also increased phospholipid DHA concentrations in liver (increase of 34% and 40%, respectively) and plasma (increase of 70% and 74%, respectively) relative to OVX. Progesterone exerted no effect on Δ6-desaturase or DHA. These results indicate that 17β-estradiol increases DHA through increased Δ6-desaturase, possibly explaining sex differences in DHA.

Total Serum Fatty Acid Analysis by GC-MS: Assay Validation and Serum Sample Stability

Analysis of n3 fatty acids in serum samples has clinical applications in supplementation trials, but the analysis can be challenging due to low levels, stability issues and intra-individual variation. This study presents the single laboratory validation of a gas chromatographic-mass spectral (GC-MS) assay for analysis of fatty acid methyl esters (FAME) using sensitive single ion monitoring and provides data on fatty acid stability under different sample handling conditions. Recovery of total fatty acids from serum with Folch extraction was optimized and parallelism tests with spiked samples indicated that the serum matrix did not interfere with mass spectral quantitation. Precision and accuracy of the assay at the lowest limit of quantitation and at low, medium and high levels met with accepted guidelines for single laboratory validation. Several storage conditions that can be encountered with clinical samples also were evaluated for impact on fatty acid levels in serum. Serum from blood that was stored refrigerated for 3 days yielded similar results as serum that was prepared and frozen at -80°C immediately. Serum storage at room temperature for 3-24 hours and serum subjected to one freeze/thaw cycle had minimal effects on fatty acid levels. The intra-individual variability in pregnant women was reasonably small, with significant correlation coefficients ranging from 0.35 to 0.76 for blood drawn between 12-20 weeks versus 34-36 weeks of gestation. These results indicate that GC-MS with single ion monitoring is valid for the analysis of total fatty acids in clinical samples, even when blood processing cannot be performed in a timely manner.

A prospective study of maternal fatty acids, micronutrients and homocysteine and their association with birth outcome

Our earlier studies both in animals and in humans have indicated that micronutrients (folic acid, vitamin B12) and long-chain polyunsaturated fatty acids, especially docosahexaenoic acid (DHA), are interlinked in the one-carbon cycle, which plays an important role in fetal 'programming' of adult diseases. The present study examines the levels of maternal and cord plasma fatty acids, maternal folate, vitamin B12 and homocysteine in healthy mothers at various time points during pregnancy and also examine an association between them. A longitudinal study of 106 normal pregnant women was carried out, and maternal blood was collected at three time points, viz., T1 = 16-20th week, T2 = 26-30th week and T3 = at delivery. Cord blood was collected at delivery. Fatty acids were estimated using a gas chromatograph. Levels of folate, vitamin B12 and homocysteine were estimated by the chemiluminescent microparticle immunoassay (CMIA) technology. Maternal plasma folate (P < 0.05), vitamin B12 (P < 0.01) and DHA (P < 0.05) levels were lowest, while maternal homocysteine levels were highest (P < 0.01) at T3. There was a negative association between maternal DHA and homocysteine at T2 (P < 0.05) and T3 (P < 0.01). There was a positive association between plasma DHA in maternal blood at T3 and cord blood. Furthermore, there was a positive association between maternal folate and vitamin B12 at T3 and baby weight, whereas maternal homocysteine at T1 were inversely associated with baby weight at delivery. Our study provides evidence for the associations of folic acid, vitamin B12, homocysteine with DHA and baby weight, suggesting that a balanced dietary supplementation of folate-vitamin B12-DHA during pregnancy may be beneficial.

Tissue-specific sex differences in docosahexaenoic acid and Δ6-desaturase in rats fed a standard chow diet

Docosahexaenoic acid (DHA, 22:6n-3) is higher in the blood and tissues of females relative to males, but the underlying mechanism is not clear. The present study examined the expression of enzymes involved in the biosynthesis of DHA from short-chain n-3 polyunsaturated fatty acids in male and female rats (n = 6 for each sex). Rats were maintained on an AIN-93G diet and sacrificed at 14 weeks of age after an overnight fast. Plasma, erythrocytes, liver, heart, and brain were collected for fatty acid composition analysis and the determination of enzyme and transcription factor expression by RT-PCR and immunoblotting. Females had higher DHA concentrations in the total lipids of liver, plasma, erythrocyte, and heart (53%, 75%, 36%, and 25% higher, respectively, compared with males) with no sex differences in brain DHA concentrations. The mRNA content of Δ5-desaturase, Δ6-desaturase, and elongase 2 was 1.0-, 1.4-, and 1.1-fold higher, respectively, in the livers of female rats compared with males, with no differences in the hearts or brains. The protein content of Δ6-desaturase was also higher in females. Higher hepatic mRNA of sterol-regulatory element-binding protein 1-c and estrogen receptor α in the females suggests that lipogenic and estrogen signaling mechanisms are involved. The sex difference in DHA concentration is tissue specific and is associated with higher Δ6-desaturase expression in females relative to males, which appears to be limited to the liver.

Preeclampsia is associated with compromised maternal synthesis of long-chain polyunsaturated fatty acids, leading to offspring deficiency

Obesity and excessive lipolysis are implicated in preeclampsia (PE). Intrauterine growth restriction is associated with low maternal body mass index and decreased lipolysis. Our aim was to assess how maternal and offspring fatty acid metabolism is altered in mothers in the third trimester of pregnancy with PE (n=62) or intrauterine growth restriction (n=23) compared with healthy pregnancies (n=164). Markers of lipid metabolism and erythrocyte fatty acid concentrations were measured. Maternal adipose tissue fatty acid composition and mRNA expression of adipose tissue fatty acid-metabolizing enzymes and placental fatty acid transporters were compared. Mothers with PE had higher plasma triglyceride (21%, P<0.001) and nonesterified fatty acid (50%, P<0.001) concentrations than controls. Concentrations of major n-6 and n-3 long-chain polyunsaturated fatty acids in erythrocytes were 23% to 60% lower (all P<0.005) in PE and intrauterine growth restriction mothers and offspring compared with controls. Subcutaneous adipose tissue Δ-5 and Δ-6 desaturase and very long-chain fatty acid elongase mRNA expression was lower in PE than controls (respectively, mean [SD] control 3.38 [2.96] versus PE 1.83 [1.91], P=0.030; 3.33 [2.25] versus 1.03 [0.96], P<0.001; 0.40 [0.81] versus 0.00 [0.00], P=0.038 expression relative to control gene [square root]). Low maternal and fetal long-chain polyunsaturated fatty acid concentrations in PE may be the result of decreased maternal synthesis.

Omega 3 fatty acids, gestation and pregnancy outcomes

Pregnancy is associated with a reduction in maternal serum docosahexaenoic acid (DHA, 22:6 n-3) percentage and its possible depletion in the maternal store. Since the synthesis of long chain polyunsaturated fatty acids (LCPUFA) in the fetus and placenta is low, both the maternal LCPUFA status and placental function are critical for their supply to the fetus. Maternal supplementation with DHA up to 1 g/d or 2·7 g n-3 LCPUFA did not have any harmful effect. DHA supplementation in large studies slightly the enhanced length of gestation (by about 2 days), which may increase the birth weight by about 50 g at delivery. However no advice can be given on their general using to avoid preterm deliveries in low or high risk pregnancies. Several studies, but not all, reported improvements of the offspring in some neurodevelopmental tests as a result of DHA supplementation during gestation, or, at least, positive relationships between maternal or cord serum DHA percentages and cognitive skills in young children. The effect seems more evident in children with low DHA proportions, which raises the question of how to identify those mothers who might have a poor DHA status and who could benefit from such supplementation. Most studies on the effects of n-3 LCPUFA supplementation during pregnancy on maternal depression were judged to be of low-to-moderate quality, mainly due to small sample sizes and failure to adhere to Consolidated Standards of Reporting Trials guidelines. In contrast, the effects of n-3 LCPUFA supplementation on reducing allergic diseases in offspring are promising.

Changes in rat n-3 and n-6 fatty acid composition during pregnancy are associated with progesterone concentrations and hepatic FADS2 expression

The mechanisms responsible for changes to long-chain polyunsaturated fatty acid (LC PUFA) status during pregnancy have not been fully elucidated. Tissue samples were collected from virgin and pregnant (day 12 and 20) female rats. LC PUFA status, sex hormone concentrations and hepatic mRNA expression of FADS1, FADS2 and elongase were assessed. Day 20 gestation females had higher plasma and liver docosahexaenoic acid and lower arachidonic acid content than virgin females (P<0.05). There was higher FADS2 mRNA expression during pregnancy (P=0.051). Progesterone and oestradiol concentrations positively correlated with hepatic FADS2 mRNA expression (P=0.043, P=0.004). Progesterone concentration positively correlated with hepatic n-6 docosapentaenoic acid content (P=0.006), and inversely correlated with intermediates in LC PUFA synthesis including n-3 docosapentaenoic acid, γ-linolenic acid and 20:2n-6 (P<0.05). Changes in progesterone and oestradiol during pregnancy may promote the synthesis of LC PUFA via increased FADS2 expression.

Dietary (n-6 : n-3) fatty acids alter plasma and tissue fatty acid composition in pregnant Sprague Dawley rats

The objective of this paper is to study the effects of varying dietary levels of n-6 : n-3 fatty acid ratio on plasma and tissue fatty acid composition in rat. The treatment groups included control rats fed chow diet only, rats fed 50% soybean oil (SBO): 50% cod liver oil (CLO) (1 : 1), 84% SBO: 16% CLO (6 : 1), 96% SBO: 4% CLO (30 : 1). Blood samples were taken at day 15 of pregnancy, and the plasma and tissue were analyzed for fatty acid profile. The n-3 PUFA in plasma of Diet 1 : 1 group was significantly higher than the other diet groups, while the total n-6 PUFA in plasma was significantly higher in Diet 30 : 1 group as compared to the control and Diet 1 : 1 groups. The Diet 1 : 1 group showed significantly greater percentages of total n-3 PUFA and docosahexaenoic acid in adipose and liver tissue, and this clearly reflected the contribution of n-3 fatty acids from CLO. The total n-6 PUFA, linoleic acid, and arachidonic acid were significantly difference in Diet 30 : 1 as compared to Diet 1 : 1 and control group. These results demonstrated that the dietary ratio of n-6 : n-3 fatty acid ratio significantly affected plasma and tissue fatty acids profile in pregnant rat.

Mechanisms involved in the selective transfer of long chain polyunsaturated Fatty acids to the fetus

The concentration of long chain polyunsaturated fatty acid (LCPUFA) in the fetal brain increases dramatically from the third trimester until 18 months of life. Several studies have shown an association between the percentage of maternal plasma docosahexaenoic acid (DHA) during gestation and development of cognitive functions in the neonate. Since only very low levels of LCPUFA are synthesized in the fetus and placenta, their primary source for the fetus is the maternal circulation. Both in vitro and human in vivo studies using labeled fatty acids have shown preferential transfer of LCPUFA from the placenta to the fetus compared with other fatty acids, although the mechanisms involved are still uncertain. The placenta takes up circulating maternal non-esterified fatty acids (NEFA) and fatty acids released mainly by maternal lipoprotein lipase and endothelial lipase. These NEFA may enter the cell by passive diffusion or by means of membrane carrier proteins. Once in the cytosol, NEFA bind to cytosolic fatty acid-binding proteins for transfer to the fetal circulation or can be oxidized within the trophoblasts, and even re-esterified and stored in lipid droplets. Although trophoblast cells are not specialized for lipid storage, LCPUFA may up-regulate peroxisome proliferator activated receptor-γ (PPARγ) and hence the gene expression of fatty acid transport carriers, fatty acid acyl-CoA-synthetases and adipophilin or other enzymes involved in lipolysis, modifying the rate of placental transfer, and metabolism. The placental transfer of LCPUFA during pregnancy seems to be a key factor in the neurological development of the fetus. Increased knowledge of the factors that modify placental transfer of fatty acids would contribute to our understanding of this complex process.

Balancing the benefits of n-3 polyunsaturated fatty acids and the risks of methylmercury exposure from fish consumption

Fish and shellfish are widely available foods that provide important nutrients, particularly n-3 polyunsaturated fatty acids (n-3 PUFAs), to many populations globally. These nutrients, especially docosahexaenoic acid, confer benefits to brain and visual system development in infants and reduce risks of certain forms of heart disease in adults. However, fish and shellfish can also be a major source of methylmercury (MeHg), a known neurotoxicant that is particularly harmful to fetal brain development. This review documents the latest knowledge on the risks and benefits of seafood consumption for perinatal development of infants. It is possible to choose fish species that are both high in n-3 PUFAs and low in MeHg. A framework for providing dietary advice for women of childbearing age on how to maximize the dietary intake of n-3 PUFAs while minimizing MeHg exposures is suggested.

Long chain polyunsaturated fatty acids in mothers of preterm babies

AIMS

to examine the levels of docosahexaenoic acid (DHA) and arachidonic acid (AA) in both plasma and erythrocytes of maternal and cord blood as well as in breast milk of mothers of preterm babies.

METHODS

a total of 63 mothers of preterm babies were recruited from the Bharati Medical Hospital, Pune, India.

RESULTS

plasma and erythrocyte DHA and AA levels were higher (P<0.001) in cord blood than in maternal blood. Maternal plasma DHA and AA were positively (P<0.01) associated with their respective maternal erythrocyte levels. There was a positive association (P<0.01) between maternal DHA (both plasma and erythrocyte) and cord DHA. Maternal plasma omega 3 and 6 fatty acids were positively (P<0.01) associated with their respective milk fatty acids.

CONCLUSIONS

higher DHA and AA levels in cord blood compared to the mothers suggests a special mechanism to meet the increased demand of the fetus. Higher levels of milk DHA reflect the increased postnatal requirement of preterm babies suggesting a vital role for maternal milk. Lower maternal erythrocyte DHA concentrations in mothers delivering preterm as compared to term suggest that increased oxidative stress may be responsible for reduced DHA levels. This may alter the uterotonic factors like prostaglandins leading to premature triggering of labor.

Do pregnant women and those at risk of developing post-natal depression consume lower amounts of long chain omega-3 polyunsaturated fatty acids?

The aims were to compare intakes of long chain omega-3 polyunsaturated fatty acid (LC n-3 PUFA) in pregnant and non-pregnant women in Australia and to compare these intakes to the Australian National Nutrition Survey of 1995 (NNS95) [1] and to determine if the LC n-3 PUFA intakes differed in women who may be ‘at risk’ compared with women ‘not at risk’ of developing post-natal depression (PND). A validated LC n-3 PUFA food frequency questionnaire and pregnant women’s Edinburgh Postnatal Depression Scale (EPDS) scores were used. LC n-3 PUFA intakes were comparable to the NNS95 but did not differ due to pregnancy or whether or not a woman is at risk of developing PND.

Elevated production of docosahexaenoic acid in females: potential molecular mechanisms

Observational evidence suggests that in populations consuming low levels of n-3 highly unsaturated fatty acids, women have higher blood levels of docosahexaenoic acid (DHA; 22:3n-6) as compared with men. Increased conversion of alpha-linolenic acid (ALA; 18:3n-3) to DHA by females has been confirmed in fatty acid stable isotope studies. This difference in conversion appears to be associated with estrogen and some evidence indicates that the expression of enzymes involved in synthesis of DHA from ALA, including desaturases and elongases, is elevated in females. An estrogen-associated effect may be mediated by peroxisome proliferator activated receptor-alpha (PPARalpha), as activation of this nuclear receptor increases the expression of these enzymes. However, because estrogens are weak ligands for PPARalpha, estrogen-mediated increases in PPARalpha activity likely occur through an indirect mechanism involving membrane-bound estrogen receptors and estrogen-sensitive G-proteins. The protein kinases activated by these receptors phosphorylate and increase the activity of PPARalpha, as well as phospholipase A(2) and cyclooxygenase 2 that increase the intracellular concentration of PPARalpha ligands. This review will outline current knowledge regarding elevated DHA production in females, as well as highlight interactions between estrogen signaling and PPARalpha activity that may mediate this effect.

Long chain polyunsaturated fatty acids in mothers and term babies

AIM

To establish the levels of docosahexaenoic acid (DHA) and arachidonic acid (AA) in both plasma and erythrocytes of maternal and cord blood as well as in breast milk of mothers delivering babies at term.

METHODS

A total of 148 mothers delivering babies at term were recruited from Bharati Medical Hospital, Pune, India.

RESULTS

Levels of DHA and AA in both plasma and erythrocyte were higher in cord blood compared to levels in maternal blood (P<0.001). Maternal plasma and erythrocyte DHA levels had a positive association with the respective levels in cord blood (P<0.001). However, such an association was not seen for AA levels. Maternal plasma omega 3 and omega 6 fatty acids were positively associated with the respective milk fatty acids (P<0.01).

CONCLUSIONS

Our results indicate that milk long-chain polyunsaturated fatty acids (LCPUFA) status reflects the concentrations of maternal LCPUFA in women delivering babies at term. Improving the maternal LCPUFA status throughout pregnancy and lactation may improve the milk LCPUFA status and ultimately benefit the infant.

Associations of maternal prenatal dietary intake of n-3 and n-6 fatty acids with maternal and umbilical cord blood levels

Maternal n-3 and n-6 polyunsaturated fatty acid (PUFA) status may influence birth outcomes and child health. We assessed second trimester maternal diet with food frequency questionnaires (FFQs) (n=1666), mid-pregnancy maternal erythrocyte PUFA concentrations (n=1550), and umbilical cord plasma PUFA concentrations (n=449). Mean (SD) maternal intake of total n-3 PUFA was 1.17 g/d (0.43), docosahexaenoic and eicosapentaenoic acids (DHA+EPA) 0.16 g/d (0.17), and total n-6 PUFA 12.25 g/d (3.25). Mean maternal erythrocyte and cord plasma PUFA concentrations were 7.0% and 5.2% (total n-3), 5.0% and 4.6% (DHA+EPA), and 27.9% and 31.4% (total n-6). Mid-pregnancy diet-blood and blood-blood correlations were strongest for DHA+EPA (r=0.38 for diet with maternal blood, r=0.34 for diet with cord blood, r=0.36 for maternal blood with cord blood), and less strong for n-6 PUFA. The FFQ is a reliable measure of elongated PUFA intake, although inter-individual variation is present.