Placental transfer of (3H)-GM1 and its distribution to maternal and fetal tissues of the rat

Supplementation with milk enriched with complex lipids during pregnancy: A double-blind randomized controlled trial

Background

Gangliosides are a class of sphingolipids that are present in the cell membranes of vertebrates. Gangliosides influence a broad range of cellular processes through effects on signal transduction, being found abundantly in the brain, and having a role in neurodevelopment.

Objective

We aimed to assess the effects of maternal daily consumption of ganglioside-enriched milk vs non-enriched milk and a non-supplemented group of pregnant women on maternal ganglioside levels and pregnancy outcomes.

Design

Double-blind parallel randomized controlled trial.

Methods

1,500 women aged 20–40 years were recruited in Chongqing (China) between 11 and 14 weeks of a singleton pregnancy, and randomized into three groups: Control–received standard powdered milk formulation (≥4 mg gangliosides/day); Complex milk lipid-enhanced (CML-E) group–same formulation enriched with complex milk lipids (≥8 mg gangliosides/day) from milk fat globule membrane; Reference–received no milk. Serum ganglioside levels were measured in a randomly selected subsample of 250 women per group.

Results

CML-E milk was associated with marginally greater total gangliosides levels in maternal serum compared to Control (13.02 vs 12.69 μg/ml; p = 0.034) but not to Reference group. CML-E milk did not affect cord blood ganglioside levels. Among the 1500 women, CML-E milk consumption was associated with a lower rate of gestational diabetes mellitus than control milk [relative risk 0.80 (95% CI 0.64, 0.99)], but which was not different to the Reference group. CML-E milk supplementation had no other effects on maternal or newborn health.

Conclusions

Maternal supplementation with milk fat globule membrane, as a source of gangliosides, was not associated with any adverse health outcomes, and did not increase serum gangliosides compared with the non-supplemented reference group.

Trial registration

Chinese Clinical Trial Register (ChiCTR-IOR-16007700).

Clinical trial registration

ChiCTR-IOR-16007700; www.chictr.org.cn/showprojen.aspx?proj=12972.

Effect of supplementation of complex milk lipids in pregnancy on fetal growth: results from the Complex Lipids in Mothers and Babies (CLIMB) randomized controlled trial

BACKGROUND

Gangliosides (GAs) are important for neuronal function and development of the brain, accumulating rapidly in the fetal brain during the last trimester of pregnancy. No study in humans has investigated whether maternal supplementation of GAs during pregnancy has an effect on fetal growth, particularly of the head circumference.

OBJECTIVE

To evaluate the effect of maternal dietary supplementation of complex milk lipids (CML; gangliosides and phospholipids) from the milk fat globule membrane (MFGM) during pregnancy on fetal growth.

DESIGN

Double-blind three-arm parallel randomized controlled trial of 1500 pregnant women from the Chongqing Municipality of China, recruited between 11 and 14 weeks of pregnancy. Intervention was in the form of supplementation with: control maternal milk formulation containing a minimum of 2 mg GA per serving (4 mg GA per day) versus a CML-enriched (CML-E) maternal milk formulation containing a minimum of 4 mg GA per serving (8 mg GA per day) versus no maternal milk supplementation, but with standard obstetric care including prenatal folic acid supplementation. Main outcomes and measures were ultrasonographically-derived estimates of fetal growth in head circumference (HC) & biparietal diameter (BPD) (primary outcomes); and abdominal circumference (AC), femur length (FL) and estimated fetal weight (EFW) (secondary outcomes) (Clinical trial registry: ChiCTR-IOR-16007700).

RESULTS

Supplementation with CML-E milk had no effects on size at midpregnancy or growth trajectories in any of the fetal biometric dimensions.

CONCLUSIONS

Supplementation of CML from the MFGM from the end of the first trimester did not have any effects on fetal growth. The absence of any adverse growth outcomes suggests that maternal MFGM supplementation during pregnancy is safe and using CML-E milk formula can be a method of providing an increased GA and phospholipid supply in early life, which has been associated with neurodevelopmental benefits.

CLINICAL TRIAL REGISTRY

ChiCTR-IOR-16007700 (http://www.chictr.org.cn/enindex.aspx).

Dietary Polar Lipids and Cognitive Development: A Narrative Review

Polar lipids are amphiphilic lipids with a hydrophilic head and a hydrophobic tail. Polar lipids mainly include phospholipids and sphingolipids. They are structural components of neural tissues, with the peak rate of accretion overlapping with neurodevelopmental milestones. The critical role of polar lipids in cognitive development is thought to be mediated through the regulation of signal transduction, myelination, and synaptic plasticity. Animal products (egg, meat, and dairy) are the major dietary sources of polar lipids for children and adults, whereas human milk and infant formula provide polar lipids to infants. Due to the differences observed in both concentration and proportion of polar lipids in human milk, the estimated daily intake in infants encompasses a wide range. In addition, health authorities define neither intake recommendations nor guidelines for polar lipid intake. However, adequate intake is defined for 2 nutrients that are elements of these polar lipids, namely choline and DHA. To date, limited studies exist on the brain bioavailability of dietary polar lipids via either placental transfer or the blood-brain barrier. Nevertheless, due to their role in pre- and postnatal development of the brain, there is a growing interest for the use of gangliosides, which are sphingolipids, as a dietary supplement for pregnant/lactating mothers or infants. In line with this, supplementing gangliosides and phospholipids in wild-type animals and healthy infants does suggest some positive effects on cognitive performance. Whether there is indeed added benefit of supplementing polar lipids in pregnant/lactating mothers or infants requires more clinical research. In this article, we report findings of a review of the state-of-the-art evidence on polar lipid supplementation and cognitive development. Dietary sources, recommended intake, and brain bioavailability of polar lipids are also discussed.

The CLIMB (Complex Lipids In Mothers and Babies) study: protocol for a multicentre, three-group, parallel randomised controlled trial to investigate the effect of supplementation of complex lipids in pregnancy, on maternal ganglioside status and subsequent cognitive outcomes in the offspring

INTRODUCTION

Complex lipids are important constituents of the central nervous system. Studies have shown that supplementation with complex milk lipids (CML) in pregnancy may increase the level of fetal gangliosides (GA), with the potential to improve cognitive outcomes.

METHODS AND ANALYSIS

We aim to recruit approximately 1500 pregnant women in the first trimester (11-14 weeks) and randomise them into one of the three treatment groups: standard maternal milk formulation, CML-enhanced maternal milk formulation or no maternal milk intervention with standard pregnancy advice (ie, the standard care). Maternal lifestyle and demographic data will be collected throughout the pregnancy, as well as biological samples (eg, blood, hair, urine, buccal smear, cord blood, cord and placenta samples). Data from standard obstetric care recorded in hospital maternity notes (eg, ultrasound reports, results of oral glucose tolerance test and pregnancy outcome data) will also be extracted. Postnatal follow-up will be at 6 weeks and 12 months of age, at which point infant cognitive development will be assessed (Bayley Scales of Infant Development I).

ETHICS AND DISSEMINATION

This project was approved by the Ethics Committee of Chongqing Medical University. Dissemination of findings will take the form of publications in peer-reviewed journals and presentations at national and international conferences.

TRIAL REGISTRATION NUMBER

ChiCTR-IOR-16007700; Pre-results.

The role of gangliosides in neurodevelopment

Gangliosides are important components of neuronal cell membranes and it is widely accepted that they play a critical role in neuronal and brain development. They are functionally involved in neurotransmission and are thought to support the formation and stabilization of functional synapses and neural circuits required as the structural basis of memory and learning. Available evidence, as reviewed herein, suggests that dietary gangliosides may impact positively on cognitive functions, particularly in the early postnatal period when the brain is still growing. Further, new evidence suggests that the mechanism of action may be through an effect on the neuroplasticity of the brain, mediated through enhanced synaptic plasticity in the hippocampus and nigro-striatal dopaminergic pathway.

Maternal supplementation with a complex milk lipid mixture during pregnancy and lactation alters neonatal brain lipid composition but lacks effect on cognitive function in rats

Complex milk lipids (CMLs) provide a critical nutritional source for generating both energy and essential nutrients for the growth of the newborn. The present study investigated nutritional supplementation with a CML containing gangliosides and phospholipids in pregnant and lactating rats on learning behavior and postnatal growth in male offspring. Wistar female rats were supplemented during pregnancy and lactation with either control or CML to provide gangliosides at a dose of 0.01% (low) and 0.05% (high) based on total food intake. The CML-supplemented dams showed no differences in comparison to controls regarding growth, food intake, and litter characteristics. There were significant differences in brain composition in male offspring at postnatal day 2 (P2) with higher concentrations of gangliosides (high dose, P < .05) and lower concentrations of phospholipids (low and high dose, P < .05) in the CML-supplemented groups. The distribution of individual ganglioside species was not significantly different between treatment groups. Brain weight at P2 was also significantly higher in the CML groups. Differences in the brain composition and weight were not significant by weaning (P21). As adults (P80), adiposity was reduced in the low CML-supplemented group compared to controls. No significant differences were detected between any of the treatment groups in any of the behavioral tasks (water maze, object recognition, and operant learning). These data suggest that maternal supplementation with a CML during pregnancy and lactation is safe and has a significant early impact on brain weight and ganglioside and phospholipid content in offspring but did not alter long-term behavioral function using standard behavioral techniques.

Maternal fumonisin exposure and risk for neural tube defects: mechanisms in an in vivo mouse model

BACKGROUND

Fumonisin B1 (FB1) is a mycotoxin produced by the fungus Fusarium verticillioides, a common contaminant of corn worldwide. FB1 disrupts sphingolipid biosynthesis by inhibiting the enzyme ceramide synthase, resulting in an elevation of free sphingoid bases and depletion of downstream glycosphingolipids. A relationship between maternal ingestion of FB1-contaminated corn during early pregnancy and increased risk for neural tube defects (NTDs) has recently been proposed in human populations around the world where corn is a dietary staple. The current studies provide an in vivo mouse model of FB1 teratogenicity.

METHODS

Pregnant LM/Bc mice were injected with increasing doses of FB1 on GD 7.5 and 8.5, and exposed fetuses were examined for malformations. Sphingolipid profiles and (3)H-folate concentrations were measured in maternal and fetal tissues. Immunohistochemical expression of the GPI-anchored folate receptor (Folbp1) and its association with the lipid raft component, ganglioside GM1, were characterized. Rescue experiments were performed with maternal folate supplementation or administration of gangliosides.

RESULTS

Maternal FB1 administration (20 mg/kg of body weight) during early gestation resulted in 79% NTDs in exposed fetuses. Sphingolipid profiles were significantly altered in maternal and embryonic tissues following exposure, and (3)H-folate levels and immunohistochemical expression of Folbp1 were reduced. Maternal folate supplementation partially rescued the NTD phenotype, whereas GM1 significantly restored folate concentrations and afforded almost complete protection against FB1-induced NTDs.

CONCLUSIONS

Maternal FB1 exposure altered sphingolipid metabolism and folate concentrations in LM/Bc mice, resulting in a dose-dependent increase in NTDs that could be prevented when adequate folate levels were maintained.

What research with animals is telling us about alcohol-related neurodevelopmental disorder

The substantial advances in understanding fetal alcohol syndrome over the past 20 years were made in large part because of research with animals. This review illustrates recent progress in animal research by focusing primarily on the central nervous system effects of prenatal alcohol exposure. Current findings suggest further progress in understanding consequences, risk factors, mechanisms, prevention and treatment will depend on continued research with animals.

Cortical cell plasma membrane alterations after in vitro alcohol exposure: prevention by GM1 ganglioside

Using choleratoxin/antitoxin immunohistochemistry, this study examined the effects of in vitro alcohol exposure on the morphology of cell plasma membranes in mixed fetal rat cortical cultures, and assessed the neuroprotective effects of exogenous monosialoganglioside (GM1). Gangliosides are involved in critical biological functions, including maintenance of membrane integrity. Plasma membranes are directly affected by alcohol exposure through multiple mechanisms. Results indicate that exposure to alcohol altered plasma membrane morphology as assessed by staining for the surface distribution of membrane GM1. Pretreatment with endogenous GM1 ameliorated the alcohol-induced alterations.

In utero ethanol exposure retards growth and alters morphology of cortical cultures: GM1 reverses effects

Ethanol, a developmental neurotoxin, alters plasma membranes' physicochemical properties affecting embryogenesis, cell migration, differentiation, and synaptogenesis. In a previous study using a model for fetal alcohol effects, GM1 ganglioside treatment was shown to reduce ethanol-induced accumulation of endogenous GM1 and fatty acid ethyl esters in rat fetuses. The present study was initiated to define further the in utero effects of ethanol and the capacity of GM1 treatment to ameliorate such effects. Wistar dams were exposed to ethanol (intragastrically) on gestation day (GD) 7 and GD8 and GD13 and GD14. GM1 ganglioside (10 mg/kg, im) was given 24 hr before ethanol administration. Cortical cultures were derived from GD15 and GD20 fetuses. GM1, which is highly localized on the cellular plasma membrane outer surface of CNS cells, was used as a marker molecule to assess cell integrity. Cholera toxin/antitoxin/fluorescence immunohistochemistry was used to localize GM1. Results indicate that the brief in utero exposure to ethanol affected cell growth and morphology. A marked retardation of cell development and arborization was observed as early as 24 hr after plating. Ethanol-exposed cells evidenced considerably altered GM1 localization. Such alterations likely reflect losses of membrane integrity. These in utero ethanol-induced pathologies are remarkably diminished in cultures derived from ethanol-exposed fetuses of dams treated with GM1.

Reduction of fatty acid ethyl ester accumulation by ganglioside GM1 in rat fetus exposed to ethanol

The biochemical mechanism of alcohol teratogenicity is not known. We have demonstrated that alcohol administration to pregnant rats during gestation days (GD) 6 and 7 and/or 13 and 14 leads to significant accumulation of ethyl esters of long chain fatty acids (FAEEs) in both maternal and fetal organs. This observation extends the report of Bearer et al. (Pediat Res 31: 492-495, 1992) who detected the presence of metabolites in maternal and fetal organs of pregnant C57B1/6J mice exposed to alcohol on GD 7 and/or GD 14. The ethyl esters of arachidonic, linoleic, oleic, stearic and palmitic acids were major metabolites detected in both maternal and fetal organs. It was also demonstrated that detectable levels of FAEEs remain 14 days (GD 20) after initial exposure to alcohol on GD 7. Ganglioside GM1 treatment 1 and 24 hr prior to alcohol exposure on both GD 7 and/or GD 14 reduced the accumulation of FAEEs. A similar regimen was shown to prevent development of tolerance to alcohol in the adult pups exposed to alcohol in utero in our previous studies. Thus, the ganglioside GM1 may have therapeutic value in reducing neurobehavioral effects of alcohol exposure in utero.

Ganglioside GM1 reduces fetal alcohol effects in rat pups exposed to ethanol in utero

We have investigated the effect of in utero ethanol exposure and ganglioside GM1 pretreatment on the endogenous ganglioside profile of the rat fetal brain. Prenatal ethanol exposure on gestation day (GD) 7 and GD8 and/or GD13 and GD14 leads to a very significant increase in the ganglioside GM1 content in at least 50% of the pup brains when assayed on GD20. This treatment protocol also results in significant decrease in the content of polysialogangliosides GD1a, GT1b, and GQ1b. GM1 treatment of pregnant dams before ethanol administration prevented this alteration in pup brain ganglioside profile. Ganglioside GM1 pretreatment appears to block the cellular membrane changes associated with fetal alcohol effects and thereby minimizes alterations in brain maturation and associated behavioral dysfunction.

Ganglioside GM1 reduces ethanol induced phospholipase A2 activity in synaptosomal preparations from mice

The adaptation (tolerance) to chronic EtOH exposure was explained by the development of resistance to the disordering of the membrane phospholipids (PL). This phenomenon may be associated with changes in enzymes such as phospholipase A2 (PLA2) that govern PL metabolism. The data presented here, using the mouse inhalation model, supports and confirms previously reported findings that chronic exposure to EtOH substantially increased PLA2 activity in synaptosomal preparations from rat brain. We have previously reported that pretreatment with ganglioside GM1 reduced the intoxicating effect of EtOH in mice. The present study indicates that GM1 pretreatment both in vivo and in vitro reduced the EtOH-induced activation of PLA2 in synaptosomal preparations. Thus GM1 may exert its neuroprotective effects by influencing deacylation/reacylation of membrane phospholipids.