Maternal-fetal in vivo transfer of [13C]docosahexaenoic and other fatty acids across the human placenta 12 h after maternal oral intake

A co-ordinated transcriptional programme in the maternal liver supplies long chain polyunsaturated fatty acids to the conceptus using phospholipids

The long and very long chain polyunsaturated fatty acids (LC-PUFAs) are preferentially transported by the mother to the fetus. Failure to supply LC-PUFAs is strongly linked with stillbirth, fetal growth restriction, and impaired neurodevelopmental outcomes. However, dietary supplementation during pregnancy is unable to simply reverse these outcomes, suggesting imperfectly understood interactions between dietary fatty acid intake and the molecular mechanisms of maternal supply. Here we employ a comprehensive approach combining untargeted and targeted lipidomics with transcriptional profiling of maternal and fetal tissues in mouse pregnancy. Comparison of wild-type mice with genetic models of impaired lipid metabolism allows us to describe maternal hepatic adaptations required to provide LC-PUFAs to the developing fetus. A late pregnancy-specific, selective activation of the Liver X Receptor signalling pathway dramatically increases maternal supply of LC-PUFAs within circulating phospholipids. Crucially, genetic ablation of this pathway in the mother reduces LC-PUFA accumulation by the fetus, specifically of docosahexaenoic acid (DHA), a critical nutrient for brain development.

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 (World health Organization 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.

Polar lipid-enriched milk fat globule membrane supplementation in maternal high-fat diet promotes intestinal barrier function and modulates gut microbiota in male offspring

Intestinal development plays a critical role in physiology and disease in early life and has long-term effects on the health status throughout the lifespan. Maternal high-fat diet (HFD) fuels the inflammatory reaction and metabolic syndrome, disrupts intestinal barrier function, and alters gut microbiota in offspring. The aim of this study was to evaluate whether polar lipid-enriched milk fat globule membrane (MFGM-PL) supplementation in maternal HFD could promote intestinal barrier function and modulate gut microbiota in male offspring. Obese female rats induced by HFD were supplemented with MFGM-PL during pregnancy and lactation. The offspring were fed HFD for 11 weeks after weaning. MFGM-PL supplementation to dams fed HFD decreased the body weight gain and ameliorated abnormalities of serum insulin, lipids, and inflammatory cytokines in offspring at weaning. Maternal MFGM-PL supplementation promoted the intestinal barrier by increasing the expression of Ki-67, lysozyme, mucin 2, zonula occludens-1, claudin-3, and occludin. Additionally, MFGM-PL supplementation to HFD dams improved gut dysbiosis in offspring. MFGM-PL increased the relative abundance of Akkermansiaceae, Ruminococcaceae, and Blautia. Concomitantly, maternal MFGM-PL treatment increased short-chain fatty acids of colonic contents and G-protein-coupled receptor (GPR) 41 and GPR 43 expressions in the colon of offspring. Importantly, the beneficial effects of maternal MFGM-PL intervention persisted to offspring's adulthood, as evidenced by increased relative abundance of norank_f_Muribaculaceae, Peptostreptococcaceae and Romboutsia and modulated the taxonomic diversity of gut microbiota in adult offspring. In summary, maternal MFGM-PL supplementation improved intestinal development in the offspring of dams fed with HFD, which exerted long-term beneficial effects on offspring intestinal health.

Fetal sex differences in placental LCPUFA ether and plasmalogen phosphatidylethanolamine and phosphatidylcholine contents in pregnancies complicated by obesity

BACKGROUND

We have previously reported that maternal obesity reduces placental transport capacity for lysophosphatidylcholine-docosahexaenoic acid (LPC-DHA), a preferred form for transfer of DHA (omega 3) to the fetal brain, but only in male fetuses. Phosphatidylethanolamine (PE) and phosphatidylcholine (PC), have either sn-1 ester, ether or vinyl ether (plasmalogen) linkages to primarily unsaturated and monounsaturated fatty acids and DHA or arachidonic acid (ARA, omega 6) in the sn-2 position. Whether ether and plasmalogen PC and PE metabolism in placenta impacts transfer to the fetus is unexplored. We hypothesized that ether and plasmalogen PC and PE containing DHA and ARA are reduced in maternal-fetal unit in pregnancies complicated by obesity and these differences are dependent on fetal sex.

METHODS

In maternal, umbilical cord plasma and placentas from obese women (11 female/5 male infants) and normal weight women (9 female/7 male infants), all PC and PE species containing DHA and ARA were analyzed by LC-MS/MS. Placental protein expression of enzymes involved in phospholipid synthesis, were determined by immunoblotting. All variables were compared between control vs obese groups and separated by fetal sex, in each sample using the Benjamini-Hochberg false discovery rate adjustment to account for multiple testing.

RESULTS

Levels of ester PC containing DHA and ARA were profoundly reduced by 60-92% in male placentas of obese mothers, while levels of ether and plasmalogen PE containing DHA and ARA were decreased by 51-84% in female placentas. PLA2G4C abundance was lower in male placentas and LPCAT4 abundance was lower solely in females in obesity. In umbilical cord, levels of ester, ether and plasmalogen PC and PE with DHA were reduced by 43-61% in male, but not female, fetuses of obese mothers.

CONCLUSIONS

We found a fetal sex effect in placental PE and PC ester, ether and plasmalogen PE and PC containing DHA in response to maternal obesity which appears to reflect an ability of female placentas to adapt to maintain optimal fetal DHA transfer in maternal obesity.

Lactoferrin/sialic acid prevents adverse effects of intrauterine growth restriction on neurite length: investigations in an in vitro rabbit neurosphere model

Introduction

Intrauterine growth restriction (IUGR) is a well-known cause of impaired neurodevelopment during life. In this study, we aimed to characterize alterations in neuronal development underlying IUGR and discover strategies to ameliorate adverse neurodevelopment effects by using a recently established rabbit in vitro neurosphere culture.

Methods

IUGR was surgically induced in pregnant rabbits by ligation of placental vessels in one uterine horn, while the contralateral horn remained unaffected for normal growth (control). At this time point, rabbits were randomly assigned to receive either no treatment, docosahexaenoic acid (DHA), melatonin (MEL), or lactoferrin (LF) until c-section. Neurospheres consisting of neural progenitor cells were obtained from control and IUGR pup's whole brain and comparatively analyzed for the ability to differentiate into neurons, extend neurite length, and form dendritic branching or pre-synapses. We established for the very first time a protocol to cultivate control and IUGR rabbit neurospheres not only for 5 days but under long-term conditions up to 14 days under differentiation conditions. Additionally, an in vitro evaluation of these therapies was evaluated by exposing neurospheres from non-treated rabbits to DHA, MEL, and SA (sialic acid, which is the major lactoferrin compound) and by assessing the ability to differentiate neurons, extend neurite length, and form dendritic branching or pre-synapses.

Results

We revealed that IUGR significantly increased the neurite length after 5 days of cultivation in vitro, a result in good agreement with previous in vivo findings in IUGR rabbits presenting more complex dendritic arborization of neurons in the frontal cortex. MEL, DHA, and SA decreased the IUGR-induced length of primary dendrites in vitro, however, only SA was able to reduce the total neurite length to control level in IUGR neurospheres. After prenatal in vivo administration of SAs parent compound LF with subsequent evaluation in vitro, LF was able to prevent abnormal neurite extension.

Discussion

We established for the first time the maintenance of the rabbit neurosphere culture for 14 days under differentiation conditions with increasing complexity of neuronal length and branching up to pre-synaptic formation. From the therapies tested, LF or its major compound, SA, prevents abnormal neurite extension and was therefore identified as the most promising therapy against IUGR-induced changes in neuronal development.

Maternal Plasma Glycerophospholipids LC-PUFA Levels Have a Sex-Specific Association with the Offspring's Cord Plasma Glycerophospholipids-Fatty Acid Desaturation Indices at Birth

Fatty acid desaturases, the enzymes responsible for the production of unsaturated fatty acids (FA) in fetal tissues, are known to be influenced by maternal-placental supply of nutrients and hormones for their function. We hypothesize that there could be a gender-specific regulation of unsaturated FA metabolism at birth, dependent on the maternal fatty acid levels. In this study, 153 mother-newborn pairs of uncomplicated and 'full-term' pregnancies were selected and the FA composition of plasma glycerophospholipids (GP) was quantified by gas chromatography. The FA composition of mother blood plasma (MB) was compared with the respective cord blood plasma (CB) of male newborns or female newborns. Product to substrate ratios were estimated to calculate delta 5 desaturase (D5D), delta 6 desaturase (D6D) and delta 9 stearoyl-CoA-desaturase (D9D/SCD) indices. Pearson correlations and linear regression analyses were employed to determine the associations between MB and CB pairs. In the results, the male infant's MB-CB association was positively correlated with the SCD index of carbon-16 FA, while no correlation was seen for the SCD index of carbon-18 FA. Unlike for males, the CB-D5D index of female neonates presented a strong positive association with the maternal n-6 long chain-polyunsaturated FA (LC-PUFA), arachidonic acid. In addition, the lipogenic desaturation index of SCD18 in the CB of female new-borns was negatively correlated with their MB n-3 DHA. In conclusion, sex-related differences in new-borns' CB desaturation indices are associated with maternal LC-PUFA status at the time of the birth. This examined relationship appears to predict the origin of sex-specific unsaturated FA metabolism seen in later life.

Altered Cord Blood Lipid Concentrations Correlate with Birth Weight and Doppler Velocimetry of Fetal Vessels in Human Fetal Growth Restriction Pregnancies

Fetal growth restriction (FGR) is associated with short- and long-term morbidity, often with fetal compromise in utero, evidenced by abnormal Doppler velocimetry of fetal vessels. Lipids are vital for growth and development, but metabolism in FGR pregnancy, where fetuses do not grow to full genetic potential, is poorly understood. We hypothesize that triglyceride concentrations are increased in placentas and that important complex lipids are reduced in cord plasma from pregnancies producing the smallest babies (birth weight &lt; 5%) and correlate with ultrasound Dopplers. Dopplers (umbilical artery, UA; middle cerebral artery, MCA) were assessed longitudinally in pregnancies diagnosed with estimated fetal weight (EFW) &lt; 10% at ≥29 weeks gestation. For a subset of enrolled women, placentas and cord blood were collected at delivery, fatty acids were extracted and targeted lipid class analysis (triglyceride, TG; phosphatidylcholine, PC; lysophosphatidylcholine, LPC; eicosanoid) performed by LCMS. For this sub-analysis, participants were categorized as FGR (Fenton birth weight, BW ≤ 5%) or SGA "controls" (Fenton BW &gt; 5%). FGRs (n = 8) delivered 1 week earlier (p = 0.04), were 29% smaller (p = 0.002), and had 133% higher UA pulsatility index (PI, p = 0.02) than SGAs (n = 12). FGR plasma TG, free arachidonic acid (AA), and several eicosanoids were increased (p &lt; 0.05); docosahexaenoic acid (DHA)-LPC was decreased (p &lt; 0.01). Plasma TG correlated inversely with BW (p &lt; 0.05). Plasma EET, non-esterified AA, and DHA correlated inversely with BW and directly with UA PI (p &lt; 0.05). Placental DHA-PC and AA-PC correlated directly with MCA PI (p &lt; 0.05). In fetuses initially referred for inadequate fetal growth (EFW &lt; 10%), those with BW ≤ 5% demonstrated distinctly different cord plasma lipid profiles than those with BW &gt; 5%, which correlated with Doppler PIs. This provides new insights into fetal lipidomic response to the FGR in utero environment. The impact of these changes on specific processes of growth and development (particularly fetal brain) have not been elucidated, but the relationship with Doppler PI may provide additional context for FGR surveillance, and a more targeted approach to nutritional management of these infants.

Measurement of lipid flux to advance translational research: evolution of classic methods to the future of precision health

Over the past 70 years, the study of lipid metabolism has led to important discoveries in identifying the underlying mechanisms of chronic diseases. Advances in the use of stable isotopes and mass spectrometry in humans have expanded our knowledge of target molecules that contribute to pathologies and lipid metabolic pathways. These advances have been leveraged within two research paths, leading to the ability (1) to quantitate lipid flux to understand the fundamentals of human physiology and pathology and (2) to perform untargeted analyses of human blood and tissues derived from a single timepoint to identify lipidomic patterns that predict disease. This review describes the physiological and analytical parameters that influence these measurements and how these issues will propel the coming together of the two fields of metabolic tracing and lipidomics. The potential of data science to advance these fields is also discussed. Future developments are needed to increase the precision of lipid measurements in human samples, leading to discoveries in how individuals vary in their production, storage, and use of lipids. New techniques are critical to support clinical strategies to prevent disease and to identify mechanisms by which treatments confer health benefits with the overall goal of reducing the burden of human disease.

Personalized tracking of how lipid (fat) metabolism changes over time could lead to improvements in the diagnosis and treatment of several diseases. Elizabeth Parks and colleagues from the University of Missouri, Columbia, USA, discuss the ways in which researchers use stable isotope labeling to monitor the kinetics of fatty acids and other lipids in the body. Usually, lipid quantities are measured only at a single timepoint, however the tracking of lipid turnover over time provides further diagnostic information. Aided by new techniques such as high-throughput mass spectrometry and machine learning, researchers are now able to continuously map total lipid contents in individual patients. The transition of measurements of lipid flux from the research laboratory to the doctor’s office will likely play a role in a new era of precision medicine.

Docosahexaenoic Acid and Melatonin Prevent Impaired Oligodendrogenesis Induced by Intrauterine Growth Restriction (IUGR)

In this study, our aims were to characterize oligodendrogenesis alterations in fetuses with intrauterine growth restriction (IUGR) and to find therapeutic strategies to prevent/treat them using a novel rabbit in vitro neurosphere culture. IUGR was surgically induced in one uterine horn of pregnant rabbits, while the contralateral horn served as a control. Neural progenitor cells (NPCs) were obtained from pup’s whole brain and cultured as neurospheres mimicking the basic processes of brain development including migration and cell differentiation. Five substances, chosen based on evidence provided in the literature, were screened in vitro in neurospheres from untreated rabbits: Docosahexaenoic acid (DHA), melatonin (MEL), zinc, 3,3′,5-Triiodo-L-thyronine (T3), and lactoferrin (LF) or its metabolite sialic acid (SA). DHA, MEL and LF were further selected for in vivo administration and subsequent evaluation in the Neurosphere Assay. In the IUGR culture, we observed a significantly reduced percentage of oligodendrocytes (OLs) which correlated with clinical findings indicating white matter injury in IUGR infants. We identified DHA and MEL as the most effective therapies. In all cases, our in vitro rabbit neurosphere assay predicted the outcome of the in vivo administration of the therapies and confirmed the reliability of the model, making it a powerful and consistent tool to select new neuroprotective therapies.

Associations of Maternal Consumption of Dairy Products during Pregnancy with Perinatal Fatty Acids Profile in the EDEN Cohort Study

Maternal diet is the main source of fatty acids for developing offspring in-utero and in breastfed infants. Dairy products (DP) are important sources of fat in the European population diet. C15:0 and C17:0 fatty acids have been suggested as biomarkers of dairy fat consumption. This study’s aim is to describe the associations between maternal DP (milk included) consumption during pregnancy and C15:0, C17:0 and polyunsaturated fatty acid (PUFA) levels in perinatal biofluids. Study populations were composed of 1763, 1337 and 879 French mothers from the EDEN (“Étude des Déterminants pre- et post-natals de la santé de l’ENfant”) study, with data on maternal and cord red blood cells’ (RBC) membrane and colostrum, respectively. Associations were assessed using linear regression models adjusted for recruitment center, maternal age, healthy dietary pattern or fish consumption. Greater adherence to a ”cheese” consumption pattern was associated with lower linoleic acid level in colostrum and higher C15:0 and C17:0 levels but in a less consistent manner for C17:0 across biofluids. Greater adherence to “semi-skimmed milk, yogurt” and “reduced-fat DP” patterns was related to higher docosahexaenoic acid and total n-3 PUFA levels and lower n-6/n-3 long-chain PUFA ratio in maternal and cord RBC. Our results suggest that C15:0 could be a good biomarker of maternal dairy fat consumption in perinatal biofluids.

Hyperandrogenism diminishes maternal-fetal fatty acid transport by increasing FABP 4-mediated placental lipid accumulation

Long-chain polyunsaturated fatty acids (LCPUFAs) are critical for fetal brain development. Infants born to preeclamptic mothers or those born growth restricted due to placental insufficiency have reduced LCPUFA, and are at higher risk for developing neurodevelopmental disorders. Since plasma levels of testosterone (T) and fatty acid-binding protein 4 (FABP4) are elevated in preeclampsia, we hypothesized that elevated T induces the expression of FABP4 in the placenta leading to compromised transplacental transport of LCPUFAs. Increased maternal T in pregnant rats significantly decreased n-3 and n-6 LCPUFA levels in maternal and fetal circulation, but increased their placental accumulation. Dietary LCPUFAs supplementation in T dams increased LCPUFA levels in the maternal circulation and further augmented placental storage, while failing to increase fetal levels. The placenta in T dams exhibited increased FABP4 mRNA and protein levels. In vitro, T dose-dependently upregulated FABP4 transcription in trophoblasts. T stimulated androgen receptor (AR) recruitment to the androgen response element and trans-activated FABP4 promoter activity, both of which were abolished by AR antagonist. T in pregnant rats and cultured trophoblasts significantly reduced transplacental transport of C14-docosahexaenoic acid (DHA) and increased C14-DHA accumulation in the placenta. Importantly, FABP4-overexpression by itself in pregnant rats and trophoblasts increased transplacental transport of C14-DHA with no significant placental accumulation. T exposure, in contrast, inhibited this FABP4-mediated effect by promoting C14-DHA placental accumulation. In summary, our studies show that maternal hyperandrogenism increases placental FABP4 expression via transcriptional upregulation and preferentially routes LCPUFAs toward cellular storage in the placenta leading to offspring lipid deficiency.

The Nutrition in Early Life and Asthma (NELA) birth cohort study: Rationale, design, and methods

BACKGROUND

Primary prevention strategies for asthma are lacking. Its inception probably starts in utero and/or during the early postnatal period as the developmental origins of health and disease (DOHaD) paradigm suggests.

OBJECTIVES

The main objective of Nutrition in Early Life and Asthma (NELA) cohort study is to unravel whether the following factors contribute causally to the developmental origins of asthma: (1) maternal obesity/adiposity and foetal growth; (2) maternal and child nutrition; (3) outdoor air pollution; (4) endocrine disruptors; and (5) maternal psychological stress. Maternal and offspring biological samples are used to assess changes in offspring microbiome, immune system, epigenome and volatilome as potential mechanisms influencing disease susceptibility.

POPULATION

Randomly selected pregnant women from three health areas of Murcia, a south-eastern Mediterranean region of Spain, who fulfilled the inclusion criteria were invited to participate at the time of the follow-up visit for routine foetal anatomy scan at 19-22 weeks of gestation, at the Maternal-Fetal Medicine Unit of the "Virgen de la Arrixaca" University Clinical Hospital over a 36-month period, from March 2015 to April 2018.

DESIGN

Prospective, population-based, maternal-child, birth cohort study.

METHODS

Questionnaires on exposures and outcome variables were administered to mothers at 20-24 gestation week; 32-36 gestation week; and delivery. Children were surveyed at birth, 3 and 18 months of age and currently at 5 years. Furthermore, physical examinations were performed; and different measurements and biological samples were obtained at these time points.

PRELIMINARY RESULTS

Among the 1350 women invited to participate, 738 (54%) were finally enrolled in the study and 720 of their children were eligible at birth. The adherence was high with 612 children (83%) attending the 3 months' visit and 532 children (72%) attending the 18 months' visit.

CONCLUSION

The NELA cohort will add original and unique knowledge to the developmental origins of asthma.

Short-term supplementation of EPA-enriched ethanolamine plasmalogen increases the level of DHA in the brain and liver of n-3 PUFA deficient mice in early life after weaning

A lack of n-3 polyunsaturated fatty acids (PUFAs) in mothers' diet significantly reduced the amount of docosahexaenoic acid (DHA) in the brains of offspring, which might affect their brain function. Our previous research has proven multiple benefits of eicosapentaenoic acid (EPA)-enriched ethanolamine plasmalogen (pPE) in enhancing the learning and memory ability. However, the effect of dietary supplementation with EPA-pPE on the DHA content in the brain and liver of offspring lacking n-3 PUFAs in early life is still unclear. Female ICR mice were fed with n-3 PUFA-deficient diets throughout the gestation and lactation periods to get n-3 PUFA-deficient offspring. The lipid profiles in the cerebral cortex and liver of offspring were analyzed using lipidomics after dietary supplementation with EPA-pPE (0.05%, w/w) and EPA-phosphatidylcholine (PC) (0.05%, w/w) for 2 weeks after weaning. Dietary supplementation with EPA could significantly change fatty acid composition in a variety of phospholipid molecular species compared with the n-3 deficient group. EPA-pPE and EPA-PC remarkably increased the DHA content in the brain PC, ether-linked phosphatidylcholine (ePC), and phosphatidylethanolamine plasmalogen (pPE) and liver triglyceride (TG), lyso-phosphatidylcholine (LPC), ePC, phosphatidylethanolamine (PE), and pPE molecular species, in which EPA-pPE showed more significant effects on the increase of DHA in cerebral cortex PC, ePC and liver PC compared with EPA-PC. Both EPA-phospholipids could effectively increase the DHA levels, and the pPE form was superior to PC in the contribution of DHA content in the cerebral cortex PC, ePC and liver PC molecular species. EPA-enriched ethanolamine plasmalogen might be a good nutritional supplement to increase DHA levels in the brains of n-3 PUFA-deficient offspring.

How the placenta-brain lipid axis impacts the nutritional origin of child neurodevelopmental disorders: Focus on attention deficit hyperactivity disorder and autism spectrum disorder

Dietary fish is a rich source of omega-3 (n-3) fatty acids, and as such, is believed to have played an important role in the evolution of the human brain and its advanced cognitive function. The long chain polyunsaturated fatty acids, particularly the n-3 docosahexanoic acid (DHA), are critical for proper neurological development and function. Both low plasma DHA and obesity in pregnancy are associated with neurodevelopmental disorders such as attention deficit and hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) in childhood, and n-3 supplementation has been shown to improve symptoms, as reviewed herein. The mechanisms underlying the connection between maternal obesity, n-3 fatty acid levels and offspring's neurological outcomes are poorly understood, but we review the evidence for a mediating role of the placenta in this relationship. Despite promising data that n-3 fatty acid supplementation mitigates the effect of maternal obesity on placental lipid metabolism, few clinical trials or animal studies have considered the neurological outcomes of offspring of mothers with obesity supplemented with n-3 FA in pregnancy.

Placental 13C-DHA metabolism and relationship with maternal BMI, glycemia and birthweight

BACKGROUND

Fetal docosahexaenoic acid (DHA) supply relies on preferential transplacental transfer, which is regulated by placental DHA lipid metabolism. Maternal hyperglycemia and obesity associate with higher birthweight and fetal DHA insufficiency but the role of placental DHA metabolism is unclear.

METHODS

Explants from 17 term placenta were incubated with 13C-labeled DHA for 48 h, at 5 or 10 mmol/L glucose treatment, and the production of 17 individual newly synthesized 13C-DHA labeled lipids quantified by liquid chromatography mass spectrometry.

RESULTS

Maternal BMI positively associated with 13C-DHA-labeled diacylglycerols, triacylglycerols, lysophospholipids, phosphatidylcholine and phosphatidylethanolamine plasmalogens, while maternal fasting glycemia positively associated with five 13C-DHA triacylglycerols. In turn, 13C-DHA-labeled phospholipids and triacylglycerols positively associated with birthweight centile. In-vitro glucose treatment increased most 13C-DHA-lipids, but decreased 13C-DHA phosphatidylethanolamine plasmalogens. However, with increasing maternal BMI, the magnitude of the glucose treatment induced increase in 13C-DHA phosphatidylcholine and 13C-DHA lysophospholipids was curtailed, with further decline in 13C-DHA phosphatidylethanolamine plasmalogens. Conversely, with increasing birthweight centile glucose treatment induced increases in 13C-DHA triacylglycerols were exaggerated, while glucose treatment induced decreases in 13C-DHA phosphatidylethanolamine plasmalogens were diminished.

CONCLUSIONS

Maternal BMI and glycemia increased the production of different placental DHA lipids implying impact on different metabolic pathways. Glucose-induced elevation in placental DHA metabolism is moderated with higher maternal BMI. In turn, findings of associations between many DHA lipids with birthweight suggest that BMI and glycemia promote fetal growth partly through changes in placental DHA metabolism.

Perinatal Dietary Polyunsaturated Fatty Acids in Brain Development, Role in Neurodevelopmental Disorders

n-3 and n-6 polyunsaturated fatty acids (PUFAs) are essential fatty acids that are provided by dietary intake. Growing evidence suggests that n-3 and n-6 PUFAs are paramount for brain functions. They constitute crucial elements of cellular membranes, especially in the brain. They are the precursors of several metabolites with different effects on inflammation and neuron outgrowth. Overall, long-chain PUFAs accumulate in the offspring brain during the embryonic and post-natal periods. In this review, we discuss how they accumulate in the developing brain, considering the maternal dietary supply, the polymorphisms of genes involved in their metabolism, and the differences linked to gender. We also report the mechanisms linking their bioavailability in the developing brain, their transfer from the mother to the embryo through the placenta, and their role in brain development. In addition, data on the potential role of altered bioavailability of long-chain n-3 PUFAs in the etiologies of neurodevelopmental diseases, such as autism, attention deficit and hyperactivity disorder, and schizophrenia, are reviewed.

Systematic Literature Review and Meta-Analysis of the Relationship Between Polyunsaturated and Trans Fatty Acids During Pregnancy and Offspring Weight Development

Eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and trans fatty acids (TFAs) may have an impact on offspring weight development. We conducted a systematic review and meta-analysis according to PRISMA guidelines to evaluate whether levels of these fatty acids during pregnancy influenced offspring weight development. Randomized controlled trials (RCTs) with DHA and/or EPA supplementation or cohort studies, which examined levels of DHA, EPA, or TFAs in maternal or neonatal blood samples and recorded offspring weight, were included. Overall, 27 RCTs and 14 observational studies were identified. The results showed that DHA and/or EPA supplementation doses >650 mg/day resulted in slightly higher birth weight (MD 87.5 g, 95% CI 52.3-122.6, n = 3,831) and combined BMI and BMI z score at 5-10 years (SMD 0.11, 95% CI 0.04-0.18, n = 3,220). These results were rated as moderate quality. Results from the observational studies were generally inconsistent. High TFA levels during pregnancy seemed to be associated with lower birth weight. Finally, this review and meta-analysis supports a relationship between high maternal or neonatal DHA and/or EPA levels and higher offspring birth weight and weight in childhood. More high-quality long-term studies are still needed.

Towards an Optimized Fetal DHA Accretion: Differences on Maternal DHA Supplementation Using Phospholipids vs. Triglycerides during Pregnancy in Different Models

Docosahexaenoic acid (DHA) supplementation during pregnancy has been recommended by several health organizations due to its role in neural, visual, and cognitive development. There are several fat sources available on the market for the manufacture of these dietary supplements with DHA. These fat sources differ in the lipid structure in which DHA is esterified, mainly phospholipids (PL) and triglycerides (TG) molecules. The supplementation of DHA in the form of PL or TG during pregnancy can lead to controversial results depending on the animal model, physiological status and the fat sources utilized. The intestinal digestion, placental uptake, and fetal accretion of DHA may vary depending on the lipid source of DHA ingested by the mother. The form of DHA used in maternal supplementation that would provide an optimal DHA accretion for fetal brain development, based on the available data obtained most of them from different animal models, indicates no consistent differences in fetal accretion when DHA is provided as TG or PL. Other related lipid species are under evaluation, e.g., lyso-phospholipids, with promising results to improve DHA bioavailability although more studies are needed. In this review, the evidence on DHA bioavailability and accumulation in both maternal and fetal tissues after the administration of DHA supplementation during pregnancy in the form of PL or TG in different models is summarized.

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.

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.

Supplementation of polar lipids-enriched milk fat globule membrane in high-fat diet-fed rats during pregnancy and lactation promotes brown/beige adipocyte development and prevents obesity in male offspring

Promoting brown adipose tissue (BAT) function or browning of white adipose tissue (WAT) provides a defense against obesity. The aim of the study was to investigate whether maternal polar lipids-enriched milk fat globule membrane (MFGM-PL) supplementation to high-fat diet (HFD) rats during pregnancy and lactation could promote brown/beige adipogenesis and protect against HFD-induced adiposity in offspring. Female SD rats were fed a HFD for 8 weeks to induce obesity and, then, fed a HFD during pregnancy and lactation with or without MFGM-PL. Male offspring were weaned at postnatal Day 21 and then fed a HFD for 9 weeks. MFGM-PL treatment to HFD dams decreased the body weight gain and WAT mass as well as lowered the serum levels of insulin and triglycerides in male offspring at weaning. MFGM-PL+HFD offspring showed promoted thermogenic function in BAT and inguinal WAT through the upregulation of UCP1 and other thermogenic genes. In adulthood, maternal MFGM-PL supplementation reduced adiposity and increased oxygen consumption, respiratory exchange ratio, and heat production in male offspring. The enhancement of energy expenditure was correlated with elevated BAT activity and inguinal WAT thermogenic program. In conclusion, maternal MFGM-PL treatment activated thermogenesis in offspring, which exerted long-term beneficial effects against HFD-induced obesity in later life.

Associations of erythrocyte fatty acid compositions with FADS1 gene polymorphism in Japanese mothers and infants

Long-chain polyunsaturated fatty acids (LC-PUFAs) are involved in the fetal growth in utero, and are essential for the development of visual and cognitive functions during infancy. The purpose of this study was to examine the associations of erythrocyte fatty acid compositions with FADS1 gene polymorphism in Japanese mothers and infants. The subjects were 383 mothers who participated in an adjunct birth cohort study of the Japan Environment and Children's Study (JECS). In maternal FADS1 SNP genotypes, the precursor fatty acids composition of the Δ5 desaturase in the maternal blood showed significant differences in levels among the groups, and showed increasing values in the order of TT < TC < CC genotype groups. On the other hand, many product fatty acids levels were significantly reduced in the order of TT > TC > CC genotype groups, and DHA levels were significantly lower in the CC genotype group relative to the other groups. Likewise, the relationship between fetal genotype group and fatty acid composition in cord blood was very similar to the maternal relationship. These results indicate the maternal and fetal blood fatty acid compositions are strongly influenced by the FADS1 genotypes. With respect to the cord blood DHA composition, the levels in the fetal CC genotype group showed a trend toward lower values in the maternal CC genotype group pair (p = 0.066) compared to the maternal TC genotype group pair. However, in the fetal TT and TC genotype groups (p = 0.131, p = 0.729, respectively), the maternal genotype did not have a significant effect. The DHA composition was more influenced by the maternal genotype in the fetal CC genotype group than in the fetal TT and TC genotype groups. It was shown that DHA transport via the placenta from the mother might be promoted in the fetal CC genotype compared to the other fetal genotype groups. In conclusion, differences in the FADS1 SNP genotypes of pregnant women and their children may greatly affect the supply of LC-PUFAs. Further studies on the involvement of the FADS1 polymorphisms and the fetal LC-PUFA levels in the fetal growth and development are warranted.

The significant role of carnitine and fatty acids during pregnancy, lactation and perinatal period. Nutritional support in specific groups of pregnant women

BACKGROUND & AIMS

Pregnancy is characterized by a complexity of metabolic processes that may impact fetal health and development. Women's nutrition during pregnancy and lactation is considered important for both mother and infant. This review aims to investigate the significant role of fatty acids and carnitine during pregnancy and lactation in specific groups of pregnant and lactating women.

METHODS

The literature was reviewed using relevant data bases (e.g. Pubmed, Scopus, Science Direct) and relevant articles were selected to provide information and data for the text and associated Tables.

RESULTS

Dynamic features especially of plasma carnitine profile during pregnancy and lactation, indicate an extraordinarily active participation of carnitine in the intermediary metabolism both in pregnant woman and in neonate and may also have implications for health and disease later in life. Maternal diets rich in trans and saturated fatty acids can lead to impairments in the metabolism and development of the offspring, whereas the consumption of long chain-polyunsaturated fatty acids during pregnancy plays a beneficial physiologic and metabolic role in the health of offspring.

CONCLUSIONS

Pregnant women who are underweight, overweight or obese, with gestational diabetes mellitus or diabetes mellitus and those who choose vegan/vegetarian diets or are coming from socially disadvantaged areas, should be nutritionally supported to achieve a higher quality diet during pregnancy and/or lactation.

The effect of high glucose on lipid metabolism in the human placenta

Diabetes mellitus (DM) during pregnancy can result in fetal overgrowth, likely due to placental dysfunction, which has health consequences for the infant. Here we test our prediction from previous work using a placental cell line that high glucose concentrations affect placental lipid metabolism. Placentas from women with type 1 (n = 13), type 2 (n = 6) or gestational (n = 12) DM, BMI-matched to mothers without DM (n = 18), were analysed for lipase and fatty acid transport proteins and fatty acid and triglyceride content. Explants from uncomplicated pregnancies (n = 6) cultured in physiological or high glucose were similarly analysed. High glucose levels did not alter placental lipase or transporter expression or the profile and abundance of fatty acids, but triglyceride levels were higher (p < 0.05), suggesting reduced β- oxidation. DM did not affect placental protein expression or fatty acid profile. Triglyceride levels of placentas from mothers with pre-existing DM were similar to controls, but higher in obese women with gestational DM. Maternal hyperglycemia may not affect placental fatty acid uptake and transport. However, placental β-oxidation is affected by high glucose and reduced in a subset of women with DM. Abnormal placental lipid metabolism could contribute to increased maternal-fetal lipid transfer and excess fetal growth in some DM pregnancies.

Prolonged Prepregnant Maternal High-Fat Feeding Reduces Fetal and Neonatal Blood Glucose Concentrations by Enhancing Fetal β-Cell Development in C57BL/6 Mice

The main objective of this study was to investigate the effect of maternal obesity on offspring's glucose metabolism during the perinatal period. Maternal obesity was established by feeding C57BL/6 mice with a high-fat (HF) diet before or during pregnancy. Our results showed that prolonged prepregnant HF feeding but not HF feeding during pregnancy significantly reduced fetal and neonatal blood glucose concentrations. Remarkably, elevated blood insulin concentrations and increased activation of insulin signaling were observed in fetuses and neonates from prepregnant HF-fed dams. In addition, significantly larger β-cell areas were observed in pancreases of fetuses and neonates from prepregnant HF-fed dams. Although there was no significant change in placental cross-sectional area or GLUT 1 expression, prepregnant HF feeding significantly enhanced the expression of genes that control placental fatty acid supply. Interestingly, reducing fatty acid supply to the placenta and fetus by placental-specific knockout of adipose triglyceride lipase not only reduced fetal β-cell area and blood insulin concentration but also attenuated prepregnant HF feeding-induced reduction in offspring blood glucose concentrations during the perinatal period. Together, these results indicate that placental and fetal fatty acid supply plays an important role in fetal β-cell development, insulin secretion, and glucose metabolism. Prolonged prepregnant maternal HF feeding resembles pregravid maternal obesity in mice, which reduces fetal and neonatal blood glucose concentrations by enhancing fetal β-cell development and insulin secretion.

In vivo kinetic study of materno-fetal fatty acid transfer in obese and normal weight pregnant women

KEY POINTS

Placental structure and function can be modified as a result of maternal obesity affecting materno-fetal fatty acids (FA) transport. We report for the first time, in humans and in vivo, the kinetics of placental FA transfer in normo-weight and in normolipemic obese pregnant women using stable isotopes. The administration of different tracer FA with similar behaviour to the mother at different time points allows the collection of kinetic information on materno-fetal transfer of FA despite only one sample of placenta and cord can be collected per subject. Computational modelling showed a good fit to the data when considering all maternal plasma lipid classes but not when based only on non-esterified FA. The novel approach using multiple tracer FA administration combined with computational modelling shows a consistent time course of placental tracer FA and predicted total FA accumulation.

ABSTRACT

We analyse for the first time the in vivo materno-fetal kinetic transfer of fatty acids (FA) labelled with stable isotopes in control and obese (OB) pregnant women. Labelled FA with a similar metabolism (stearic acid: ¹³ C-SA; palmitic acid: ¹³ C-PA; oleic acid: ¹³ C-OA) were orally administered at -4 h, -8 h and -12 h, respectively prior to elective caesarean section to 10 pregnant women with a body mass index >30 (OB) and 10 with a body mass index in the range 20-25 (NW). Placenta, venous and arterial cord blood were collected obtaining a wide range of FA enrichments. A combined experimental and computational modelling analysis was applied. FA fractional synthesis rate (FSR) in placenta was 11-12% h^-1 . No differences were observed between NW and normo-lipidemic OB. It was not possible to estimate FA FSR in cord blood with this oral bolus dose approach. Computational modelling demonstrated a good fit to the data when all maternal plasma lipid classes were included but not with modelling based only on the non-esterified FA fraction. The estimated materno-fetal ¹³ C-FA transfer was ∼1%. In conclusion, our approach using multiple ¹³ C-FA tracers allowed us to estimated FSR in placental/maternal plasma but not in fetal/maternal compartments. Computational modelling showed a consistent time course of placental ¹³ C-FA transfer and predicted total fetal FA accumulation during the experiment. We conclude that, in addition to non-esterified FA fraction in the maternal circulation, maternal plasma very low-density lipoprotein and other lipoproteins are important contributors to placental FA transfer to the fetus.

Metabolism of 13C-Labeled Fatty Acids in Term Human Placental Explants by Liquid Chromatography-Mass Spectrometry

Placental lipid transport and metabolism are poorly understood despite the importance for fetal development and lifelong health. We aimed to explore fatty acid (FA) processing in human villous placental explants from seven uncomplicated term singleton pregnancies delivered by elective cesarean section. Explants were treated with stable isotope-labeled palmitic acid (13C-PA), oleic acid (13C-OA), or docosahexaenoic acid (13C-DHA) for 3, 24, or 48 hours. Stable isotope-labeled lipids synthesized by placental explants from labeled FA were quantified, alongside endogenous unlabeled placental lipids, by liquid chromatography-mass spectrometry. Labeled phosphatidylcholines (PCs), triacylglycerols (TAGs), and phosphatidylethanolamines were detected in explants, whereas labeled lysophosphatidylcholines were found in both explants and conditioned media. 13C-PA was primarily directed into PC synthesis (74% of 13C-PA-labeled lipids), whereas 13C-OA was directed almost equally into PC and TAG synthesis (45% and 53%, respectively, of 13C-OA-labeled lipids). 13C-DHA was only detectable in TAGs. TAGs demonstrated the highest isotopic enrichment for all 13C-FAs with 13C-OA-TAGs comprising >50% of total OA-TAGs (unlabeled and labeled), consistent with TAGs being a labile and accessible reservoir for FA storage. Variations in lipid incorporation were correlated to maternal glycemia and body mass index, suggesting that this experimental model could be used to investigate the effect of maternal factors on placental lipid metabolism. We conclude that lipid metabolic partitioning of freshly imported FAs into labile and less labile lipid reservoirs in placenta is FA dependent. This process may partly mediate the physiological preferential transplacental transfer of particular FAs to the fetus, but may also be implicated in the fetoplacental pathophysiology of maternal metabolic dysfunction.

Maternal obesity results in decreased syncytiotrophoblast synthesis of palmitoleic acid, a fatty acid with anti-inflammatory and insulin-sensitizing properties

The fetus is dependent on delivery of fatty acids (FAs) by the syncytiotrophoblast, the transporting epithelium of the human placenta. Obese pregnant women have dyslipidemia; however, whether obesity impacts placental lipid transport and metabolism remains to be fully established. Palmitoleic acid (POA), an FA with anti-inflammatory and insulin-sensitizing properties, is synthesized from palmitic acid (PA) catalyzed by stearoyl-coenzyme A desaturase (SCD) activity. We hypothesized that the uptake and incorporation of FAs and POA synthesis are reduced in primary human trophoblasts (PHTs) isolated from pregnancies complicated by maternal obesity. Villous cytotrophoblasts were isolated from 7 placentas of obese [body mass index (BMI) = 37.5 ± 1.9] and 12 normal (BMI = 23.6 ± 0.6) mothers. FA uptake and incorporation were assessed using uniformly labeled (U[13C])-FA mixtures of PA, oleic acid (OA), linoleic acid, and docosahexaenoic acid. Cellular [13C] FAs were quantified both in total cellular lipids and in lipid classes by GC-MS. Uptake and incorporation of [13C] FAs in total cellular lipids were not different in PHTs isolated from obese mothers compared with normal mothers. Only the concentration of OA was increased in the triglyceride fraction (P < 0.05) if the mother was obese. We found an isotopic enrichment of POA after U[13C]-PA treatment, demonstrating SCD activity in PHT cells. Labeled POA content and the POA:PA ratio were significantly lower in PHTs isolated from placentas of obese mothers compared with normal, healthy controls. Decreased syncytiotrophoblast POA synthesis may contribute to insulin resistance and low-grade inflammation in the mother, placenta, or fetus (or a combination of the 3) in pregnancies complicated by obesity.-Ferchaud-Roucher, V., Barner, K., Jansson, T., Powell, T. L. Maternal obesity results in decreased syncytiotrophoblast synthesis of palmitoleic acid, a fatty acid with anti-inflammatory and insulin-sensitizing properties.

Altered materno-fetal transfer of 13C-polyunsaturated fatty acids in obese pregnant women

BACKGROUND & AIMS

Maternal obesity at conception is considered a major predictor of offspring obesity. This could by driven at least in part by an altered placental fat transfer. However, the pathophysiological mechanisms involved are not fully understood. We investigated the in vivo materno-fetal transfer of fatty acids (FAs) in obese pregnant women using stable isotopes.

METHODS

Ten obese and ten normo-weight pregnant women (control) received orally a bolus of ¹³C-labeled FAs 12 h before elective caesarean section: oleic acid (¹³C-OA), linoleic acid (¹³C-LA) and docosahexaenoic acid (¹³C-DHA). Maternal blood samples were collected at -12 (basal), -8, -4, -2, 0 h relative to the time of cesarean section. At the time of birth, arterial and venous cord bloods as well as placental tissue were collected. FAs composition was determined by gas-liquid chromatography and isotopic enrichment by gas chromatography-combustion-isotope ratio mass spectrometry.

RESULTS

Maternal plasma insulin and placental weight tended to higher values in obese pregnant women although they did not present serum hyperlipidemia. Higher concentrations of ¹³C-LA and ¹³C-DHA were found in non-esterified FAs fraction in maternal plasma of obese mothers. The ratio of placental uptake for ¹³C-LA and ¹³C-DHA was lower in obese women compared to normal weight pointing toward a limited capacity of FA placental transfer, especially of essential FAs. Maternal insulin was associated to this lower placenta/maternal plasma ratio for both ¹³C-LA (R = -0.563, P = 0.012) and ¹³C-DHA (R = -0.478, P = 0.033). In addition, the ratio cord/maternal plasma of ¹³C-LA was significantly lower in obese women compared to controls.

CONCLUSIONS

In conclusion, obese mothers without hyperlipidemia showed a reduced materno-fetal transfer of polyunsaturated FAs which could affect fetal development. This affect dietary recommendation for obese pregnant women.

TRIAL REGISTRY NUMBER

ISRCTN69794527.

Perinatal nutrition impacts on the functional development of the visual tract in infants

BACKGROUND AND OBJECTIVE

We investigated the associations of maternal diet and serum fatty acids during pregnancy and in early infancy on infantile neurodevelopment.

METHODS

Pattern-reversal visual evoked potentials (pVEP) as depictors of central nervous system maturation were recorded from 56 children when they were 2 years old. Maternal nutrient intakes were calculated from food diaries and fish consumption from questionnaires collected during pregnancy. Serum phospholipid fatty acids were determined by gas chromatography in late pregnancy and from infants at 1 month of age.

RESULTS

The children of the women who consumed fish three or more times per week during the last trimester of pregnancy had a higher pVEP component P100 amplitude for 60' (mean 23.4, SD 8.1) and 30' (mean 20.4, SD 6.7) of arcminute check sizes compared to those who consumed fish 0-2 times per week (mean 15.0, SD 4.8, p = 0.023, adjusted for birth weight and gender p = 0.058 and mean 13.4, SD 2.0, respectively, p = 0.028, adjusted p = 0.072). Maternal and child serum phospholipid fatty acids correlated with child pVEP measurements.

CONCLUSION

The results of this small-scale study suggest that fish consumption during pregnancy and perinatal serum fatty acid status may associate with neurodevelopment within visual system during infancy.

Maternal obesity leads to long-term altered levels of plasma ceramides in the offspring as revealed by a longitudinal lipidomic study in children

BACKGROUND/OBJECTIVES

Maternal obesity is associated with increased risk of obesity and other symptoms of the metabolic syndrome in the offspring. Nevertheless, the molecular mechanisms and cellular factors underlying this enhanced disease susceptibility remain to be determined. Here, we aimed at identifying changes in plasma lipids in offspring of obese mothers that might underpin, and serve as early biomarkers of, their enhanced metabolic disease risk.

SUBJECTS/METHODS

We performed a longitudinal lipidomic profiling in plasma samples from normal weight, overweight, and obese pregnant women and their children that participated in the Prenatal Omega-3 Fatty Acid Supplementation, Growth, and Development trial conducted in Mexico. At recruitment women were aged between 18 and 35 years and in week 18-22 of pregnancy. Blood samples were collected at term delivery by venipuncture from mothers and from the umbilical cord of their newborns and from the same infants at 4 years old under non-fasting conditions. Lipidomic profiling was done using ultra-performance liquid chromatography high-resolution mass spectrometry.

RESULTS

Analysis of the lipidomic data showed that overweight and obese mothers exhibited a significant reduction in the total abundance of ceramides (Cer) in plasma, mainly of Cer (d18:1/20:0), Cer (d18:1/22:0), Cer (d18:1/23:0), and Cer (d18:1/24:0), compared with mothers of normal body weight. This reduction was confirmed by the direct quantification of these and other ceramide species. Similar quantitative differences in the plasma concentration of Cer (d18:1/22:0), Cer (d18:1/23:0), and Cer (d18:1/24:0), were also found between 4-year-old children of overweight and obese mothers compared with children of mothers of normal body weight. Noteworthy, children exhibited equal daily amounts of energy and food intake independently of the BMI of their mothers.

CONCLUSIONS

Maternal obesity results in long-lasting changes in plasma ceramides in the offspring suggesting that these lipids might be used as early predictors of metabolic disease risk due to maternal obesity.

Insights into major facilitator superfamily domain-containing protein-2a (Mfsd2a) in physiology and pathophysiology. What do we know so far?

Major facilitator superfamily domain-containing protein-2a (Mfsd2a) which was considered as an orphan transporter has recently gained attention for its regulatory role in the maintenance of proper functioning of the blood-brain barrier. Besides the major role of Mfsd2a in maintaining the barrier function, increasing evidence has emerged with regard to the contributions of Mfsd2a to various biological processes such as transport, cell fusion, cell cycle, inflammation and regeneration, managing tumor growth, functioning of other organs with barrier functions or responses to injury. The purpose of this article is to review the different roles of Mfsd2a and its involvement in the physiological and pathophysiological processes primarily in the central nervous system and throughout the mammalian body under the lights of the current literature.

A diet enriched in longer chain omega-3 fatty acids reduced placental inflammatory cytokines and improved fetal sustainability of C57BL/6 mice

Omega (n)-3 polyunsaturated fatty acids (PUFA) are important regulators of inflammatory response that may impact pregnancy outcome. The effects of breeding chow diets containing n-3 PUFA from either fish oil (FO) or soybean oil (SO) were investigated on tissue fatty acid composition, inflammatory cytokines and pregnancy outcome. Female C57BL/6 mice (7 weeks old) were fed FO or SO diets for 2 weeks before mating and throughout pregnancy. Animals were sacrificed before and during pregnancy at day 6.5, 12.5 and 18.5. The FO diet increased the incorporation of n-3 PUFA in placenta, with a concomitant decrease in the concentration of pro-inflammatory cytokines. The FO diet increased the mRNA expression of placental specific PUFA transporter, which coincided with accretion of n-3 PUFA in fetal brain. Sites of fetal resorption were noticeable in the SO group but not in the FO group. N-3 PUFA may improve fetal sustainability via altering cytokine levels.

Real-time microscopic assessment of fatty acid uptake kinetics in the human term placenta

INTRODUCTION

The placenta employs an efficient and selective fatty acid transport system to supply lipids for fetal development. Disruptions in placental fatty acid transport lead to restricted fetal growth along with cardiovascular and neurologic deficits. Nevertheless, little is known about the molecular mechanisms involved in human placental fatty acid trafficking during the initial steps of uptake, or the importance of fatty acid chain length in determining uptake rates.

METHODS

We employed BODIPY fluorophore conjugated fatty acid analogues of three chain lengths, medium (BODIPY-C5), long (BODIPY-C12), and very-long (BODIPY-C16), to study fatty acid uptake in isolated human trophoblast and explants using confocal microscopy. The three BODIPY-labeled fatty acids were added to freshly isolated explants and tracked for up to 30 min. Fatty acid uptake kinetics were quantified in trophoblast (cytotrophoblast and syncytiotrophoblast together) and the fetal capillary lumen.

RESULTS

Long- (BODIPY-C12) and Very long-chain (BODIPY-C16) fatty acids accumulated more rapidly in the trophoblast layer than did medium-chain (BODIPY-C5) whereas BODIPY-C5 accumulated more rapidly in the fetal capillary than did the longer chain length fatty acids. The long-chain fatty acids, BODIPY-C12 and BODIPY-C16, are esterified and stored in lipid droplets in the cytotrophoblast layer, but medium-chain fatty acid, BODIPY-C5, is not.

DISCUSSION

Fatty acids accumulate in trophoblast and fetal capillaries inversely according to their chain length. BODIPY-C5 accumulates in the fetal capillary in concentrations far greater than in the trophoblast, suggesting that medium-chain length BODIPY-labeled fatty acids are capable of being transported against a concentration gradient.

Distribution of Fatty Acids and Lipids During Pregnancy

Maternal fatty acid and lipid metabolism undergoes changes during pregnancy to facilitate fetal growth and development. Different types of fatty acids have different roles in maintaining a successful pregnancy and they are incorporated into different forms of lipids for the purpose of storage and transport. This chapter aims to provide an understanding of the distribution and metabolism of fatty acids and lipids in the maternal, placental, and fetal compartments. We further describe how this distribution is altered in maternal obesity, preterm birth, and pregnancy complications such as gestational diabetes mellitus, preeclampsia, and intrauterine growth restriction.

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.

Supplementation of docosahexaenoic acid (DHA) / Eicosapentaenoic acid (EPA) in a ratio of 1/1.3 during the last trimester of pregnancy results in EPA accumulation in cord blood

Omega-3 fatty acids (n-3 FA), specifically DHA, are associated with fetal growth and development. We aimed to determine the levels of DHA and EPA in cord serum after n-3 FA supplementation during the last trimester of pregnancy. Among 55 women, 23 were administered daily one capsule of n-3 FA supplement, involving DHA/EPA in a ratio of 1/1.3. Twenty nine women were enrolled as control group. Blood samples were collected at 22-24 weeks of gestation and at delivery. Fatty acids were analyzed with the method of GC-MS. Cord DHA level increased and EPA level decreased in both groups between the days of 22-24 and delivery. However, decrease in cord EPA level was significant in control group (p < 0.001) but not in supplement group (p > 0.05). Supplementation of DHA/EPA in a ratio of 1/1.3 during the last trimester of pregnancy caused higher cord EPA level compared to control group indicating an accumulation in umbilical cord.

Fatty acid profile of maternal and fetal erythrocytes and placental expression of fatty acid transport proteins in normal and intrauterine growth restriction pregnancies

Long-chain polyunsaturated fatty acids (LC-PUFA), mainly docosahexaenoic (DHA) and arachidonic acids (AA), are critical for adequate fetal growth and development. We investigated mRNA expression of proteins involved in hydrolysis, uptake and/or transport of fatty acids in placenta of fifteen full term normal pregnancies and eleven pregnancies complicated by intrauterine growth restriction (IUGR) with normal umbilical blood flows. The mRNA expression of LPL, FATPs (-1, -2 and -4) and FABPs (-1 and -3) was increased in IUGR placentas, however, tissue profile of LC-PUFA was not different between groups. Erythrocytes from both mothers and fetuses of the IUGR group showed lower concentrations of AA and DHA and inferior DHA/ALA ratio compared to normal pregnancies (P < 0.05). We hypothesize that reduced circulating levels of AA and DHA could up-regulate mRNA expression of placental fatty acids transporters, as a compensatory mechanism, however this failed to sustain normal LC-PUFA supply to the fetus in IUGR.

Docosahexaenoic acid (DHA) accretion in the placenta but not the fetus is matched by plasma unesterified DHA uptake rates in pregnant Long Evans rats

Maternal delivery of docosahexaenoic acid (DHA, 22:6n-3) to the developing fetus via the placenta is required for fetal neurodevelopment, and is the only mechanism by which DHA can be accreted in the fetus. The aim of the current study was to utilize a balance model of DHA accretion combined with kinetic measures of serum unesterified DHA uptake to better understand the mechanism by which maternal DHA is delivered to the fetus via the placenta. Female rats maintained on a 2% α-linolenic acid diet free of DHA for 56 days were mated, and for balance analysis, sacrificed at 18 days of pregnancy, and fetus, placenta and maternal carcass fatty acid concentration were determined. For tissue DHA uptake, pregnant dams (14-18 days) were infused for 5 min with radiolabeled ¹⁴C-DHA and kinetic modeling was used to determine fetal and placental serum unesterified DHA uptake rates. DHA accretion rates in the fetus were determined to be 38 ± 2 nmol/d/g, 859 ± 100 nmol/d/litter and 74 ± 3 nmol/d/pup, which are all higher (P < 0.05) than the fetal serum unesterified DHA uptake rates of 16 ± 6 nmol/d/g, 239 ± 145 nmol/d/litter and 14 ± 8 nmol/d/pup. No differences (p > 0.05) in placental DHA accretion rates versus serum unesterified DHA uptake rates were observed as values varied only 6-35% between studies. No differences in placental accretion and uptake rates suggests that serum unesterified DHA is a significant pool for the maternal-placental transfer of DHA, and lower fetal DHA uptake compared to accretion supports remodeling of placental DHA for delivery to the fetus.

Fatty acid and lipid profiles in primary human trophoblast over 90h in culture

Little is known about the mechanisms underlying the preferential transport of long chain polyunsaturated fatty acids (LCPUFA) to the fetus by the syncytiotrophoblast and the role of cytotrophoblasts in placental lipid metabolism and transport. We studied primary human trophoblast (PHT) cells cultured for 90h to determine the fatty acid and lipid composition of cytotrophoblast (18h culture) and syncytiotrophoblast (90h culture) cells. In cultured PHT total lipid fatty acids were significantly (P < 0.05) reduced at 90h compared to 18h in culture including lower levels of palmitic acid (PA, 16:0, -37%), palmitoleic acid (POA, 16:1n-7, -30%), oleic acid (OA, 18:1n-9, -31%), LCPUFA arachidonic acid (AA, 20:4n-6, -28%) and α-linolenic acid (ALA, 18:3n-3, -55%). In major lipid classes, OA and most of the n-3 and n-6 LCPUFA were markedly lower at 90h in TG (-57 to -76%; p < 0.05). In the cellular NEFA, n-6 LCPUFA, dihomo-γ-linolenic acid (DGLA, 20:3n-6) and AA were both reduced by -51% and DHA was -55% lower (p < 0.05) at 90h. In contrast, phospholipid FA content did not change between cytotrophoblasts and syncytiotrophoblast except for OA, which decreased by -62% (p < 0.05). Decreasing PHT TG and NEFA lipid content at 90h in culture is likely due to processes related to differentiation such as alterations in lipase activity that occur as cytotrophoblast cells differentiate. We speculate that syncytiotrophoblast prioritizes PL containing AA and DHA for transfer to the fetus by mobilizing FA from storage lipids.

Maternal and fetal lipid metabolism under normal and gestational diabetic conditions

Maternal lipids are strong determinants of fetal fat mass. Here we review the overall lipid metabolism in normal and gestational diabetes mellitus (GDM) pregnancies. During early pregnancy, the increase in maternal fat depots is facilitated by insulin, followed by increased adipose tissue breakdown and subsequent hypertriglyceridemia, mainly as a result of insulin resistance (IR) and estrogen effects. The response to diabetes is variable as a result of greater IR but decreased estrogen levels. The vast majority of fatty acids (FAs) in the maternal circulation are esterified and associated with lipoproteins. These are taken up by the placenta and hydrolyzed by lipases. The released FAs enter various metabolic routes and are released into fetal circulation. Although these determinants are modified in maternal GDM, the fetus does not seem to receive more FAs than in non-GDM pregnancies. Long-chain polyunsaturated FAs are essential for fetal development and are obtained from the mother. Mitochondrial FA oxidation occurs in fetal tissue and in placenta and contributes to energy production. Fetal fat accretion during the last weeks of gestation occurs very rapidly and is sustained not only by FAs crossing the placenta, but also by fetal lipogenesis. Fetal hyperinsulinemia in GDM mothers promotes excess accretion of adipose tissue, which gives rise to altered adipocytokine profiles. Fetal lipoproteins are low at birth, but the GDM effects are unclear. The increase in body fat in neonates of GDM women is a risk factor for obesity in early childhood and later life.

Should Women Providing Milk to Their Preterm Infants Take Docosahexaenoic Acid Supplements?

Based on the available data, a high milk docosahexaenoic acid supply to very low-birth-weight infants and to extremely low-birth-weight infants at levels that support tissue accretion rates similar to the high rates of intrauterine deposition has the potential to enhance the early visual and cognitive development, and to reduce the occurrence of adverse events, such as severe developmental delay, bronchopulmonary dysplasia, necrotizing enterocolitis, and allergic manifestations in infancy and early childhood. Possibly subgroups of preterm infants achieve greater benefits as well as infants with genotypes predicting a low rate of endogenous long-chain polyunsaturated fatty acids formation.

Trans fatty acid accumulation in the human placenta

Trans fatty acid may impair fetal growth and infant neurodevelopment, but the quantity in a placenta and human tissues remains unknown. To address the issue, a simple and reliable method of quantification is needed. We established a method of quantifying trans-octadecenoic acids (trans-6,8,9,11 18:1 fatty acids, TOAs), a major component of trans fatty acid, in human tissue samples, and then determined the TOAs level in the placenta. Oleic acid (OA) (C18:1(9c)) was measured by isotope dilution gas chromatography-mass spectrometry, and the TOAs level was subsequently calculated based on the ratio of the peak areas for TOAs and OA (TOAs/OA) in the mass chromatogram. Lipids were extracted from 28 human placentas at different gestational ages from 28 to 41 weeks, and the TOAs and OA levels were measured. In method validation, the limit of detection for elaidic acid (trans-9,18:1 fatty acid), a major component of TOAs, was 0.57 ng, and linearity of calibration ranging from 7.7 to 68.0 μg/g placenta for TOAs. In human placenta analysis, the TOAs level was significantly higher in term (n = 15, 40.2 ± 9.7 μg/g placenta) than in preterm placentas (n = 13, 18.9 ± 7.4 μg/g placenta) (p < 0.001), while OA levels were similar in term (n = 15, 863 ± 132 μg/g placenta) and preterm (n = 13, 743 ± 283 μg/g placenta) placentas (p = 0.15). TOAs accumulate in the placenta as pregnancy progresses and have a fate different from that of OA in vivo. To our knowledge, this is the first report of TOA quantification in human tissue samples. Copyright © 2017 John Wiley & Sons, Ltd.

Opportunities for probiotics and polyunsaturated fatty acids to improve metabolic health of overweight pregnant women

Overweight during pregnancy predisposes both the mother and foetus to health complications. Maternal complications include gestational diabetes, obstetric problems and type 2 diabetes later in life. Complications for the offspring are not only restricted to the foetal period or birth, such as prematurity and foetal macrosomia, but may also have long-term metabolic health implications through the mechanism of early nutrition programming. One of the key metabolic components characterising overweight in the non-pregnant state is low-grade inflammation manifested by elevated levels of circulatory pro-inflammatory cytokines. In pregnancy, in addition to adipose tissue and placenta, inflammatory response may originate from the gut. The extent to which overweight induces metabolic maladaptation during pregnancy and further compromises maternal and child health is currently poorly understood. In this review, we evaluate recent scientific literature and describe the suggested links between overweight, gut and low-grade inflammation associated metabolic disorders. We focus on overweight pregnant women and gestational diabetes, and discuss how specific dietary factors, probiotics and long-chain polyunsaturated fatty acids (fish oil), might confer health benefits in combatting against metabolic risk factors.

Docosahexaenoic acid supplementation during pregnancy as phospholipids did not improve the incorporation of this fatty acid into rat fetal brain compared with the triglyceride form

Prenatal docosahexaenoic acid (DHA) supply is important to ensure an adequate infant neurodevelopment. Several fat supplements with DHA under different chemical structures are available. There is an increased placental phospholipase activity at the end of pregnancy. The hypothesis of this study was to discern whether DHA consumption during pregnancy as phospholipids (PLs) could be more available for placental DHA uptake and fetal accretion than triglycerides (TGs) form. We aimed to evaluate maternofetal DHA status in pregnant rats fed with DHA as PL from egg yolk or TG from algae oil to determine which source might be most effective during pregnancy. Three experimental diets were tested: 2.5% DHA-TG (n = 10), 2.5% DHA-PL (n = 9), and 9% DHA-PL (n = 9). The total PL content of these diets was 2%, 12%, and 38%, respectively. We determined dietary fat absorption and quantified fatty acids by gas chromatography in maternal and fetal tissues. Dietary PL enhanced significantly dietary fat absorption. However, animals fed the highest PL-content diet (38% PL and 9% DHA-PL) stored most of the absorbed fat in maternal liver, promoting hepatic steatosis, which was not observed in the lower PL-content diets (12% and 2%). Despite higher fat absorption of PL-containing diets, maternal and fetal tissues (including fetal brain) did not show major differences in DHA content between the 2.5% DHA-PL and 2.5% DHA-TG-fed groups. We conclude that the chemical form of DHA consumed by the rat during gestation (PL or TG) does not differentially affect DHA accretion into fetal brain, and both lipid sources can be equally used for maternal DHA supplementation during pregnancy.

Lipid metabolism is associated with developmental epigenetic programming

Maternal diet and metabolism impact fetal development. Epigenetic reprogramming facilitates fetal adaptation to these in utero cues. To determine if maternal metabolite levels impact infant DNA methylation globally and at growth and development genes, we followed a clinical birth cohort of 40 mother-infant dyads. Targeted metabolomics and quantitative DNA methylation were analyzed in 1st trimester maternal plasma (M1) and delivery maternal plasma (M2) as well as infant umbilical cord blood plasma (CB). We found very long chain fatty acids, medium chain acylcarnitines, and histidine were: (1) stable in maternal plasma from pregnancy to delivery, (2) significantly correlated between M1, M2, and CB, and (3) in the top 10% of maternal metabolites correlating with infant DNA methylation, suggesting maternal metabolites associated with infant DNA methylation are tightly controlled. Global DNA methylation was highly correlated across M1, M2, and CB. Thus, circulating maternal lipids are associated with developmental epigenetic programming, which in turn may impact lifelong health and disease risk. Further studies are required to determine the causal link between maternal plasma lipids and infant DNA methylation patterns.

Real-Time Tracking of BODIPY-C12 Long-Chain Fatty Acid in Human Term Placenta Reveals Unique Lipid Dynamics in Cytotrophoblast Cells

While the human placenta must provide selected long-chain fatty acids to support the developing fetal brain, little is known about the mechanisms underlying the transport process. We tracked the movement of the fluorescently labeled long-chain fatty acid analogue, BODIPY-C₁₂, across the cell layers of living explants of human term placenta. Although all layers took up the fatty acid, rapid esterification of long-chain fatty acids and incorporation into lipid droplets was exclusive to the inner layer cytotrophoblast cells rather than the expected outer syncytiotrophoblast layer. Cytotrophoblast is a progenitor cell layer previously relegated to a repair role. As isolated cytotrophoblasts differentiated into syncytialized cells in culture, they weakened their lipid processing capacity. Syncytializing cells suppress previously active genes that regulate fatty-acid uptake (SLC27A2/FATP2, FABP4, ACSL5) and lipid metabolism (GPAT3, LPCAT3). We speculate that cytotrophoblast performs a previously unrecognized role in regulating placental fatty acid uptake and metabolism.