Lactational changes in concentration and distribution of ganglioside molecular species in human breast milk from Chinese mothers

Trajectories of Human Milk Gangliosides during the First Four Hundred Days and Maternal-to-Offspring Transfer of Gangliosides: Results from a Chinese Cohort Study

BACKGROUND

Gangliosides are crucial for early-life cognition and immunity development. However, limited data exist on gangliosides within the Chinese population, and maternal-to-fetal/infant ganglioside transport remains unclear.

OBJECTIVES

This study aimed to investigate gangliosides concentrations and trajectories in Chinese human milk during the first 400 d of lactation, and seek to understand gangliosides transmission between mother and offspring.

METHODS

This study involved 921 cross-sectional participants providing human milk samples across 0-400 d of lactation and 136 longitudinal participants offering maternal plasma, cord plasma, and human milk samples within the first 45 d postpartum. Ultrahigh-performance liquid chromatography-tandem mass spectrometry was used for the quantification of gangliosides.

RESULTS

Human milk GM3 (Neu5Acα2-3Galβ1-4GlcβCer) concentration increased from 2.29 ± 1.87 to 13.93 ± 4.82 μg/mL, whereas GD3 (Neu5Acα2-8Neu5Acα2-3Galβ1-4GlcβCer) decreased from 17.94 ± 6.41 to 0.30 ± 0.50 μg/mL during the first 400 d postpartum (all P < 0.05). Consistent results were observed in cross-sectional and longitudinal participants. GD3 concentration gradually increased from maternal plasma (1.58 μg/mL) through cord plasma (2.05 μg/mL) to colostrum (21.35 μg/mL). Significant positive correlations were observed between maternal and cord plasma for both GM3 (r = 0.30, P < 0.001) and GD3 (r = 0.35, P < 0.001), and maternal plasma GD3 also correlated positively with colostrum concentrations (r = 0.21, P = 0.015). Additionally, in maternal and cord plasma, gangliosides were mainly linked with 16- and 18-carbon fatty acids. However, human milk GM3 showed a broad spectrum of fatty acid chain lengths, whereas GD3 was primarily tied to very long-chain fatty acids (≥20 carbon).

CONCLUSIONS

We identified an increase in GM3 and a decrease in GD3 concentration in human milk, with GD3 notably more concentrated in cord plasma and colostrum. Importantly, ganglioside concentrations in maternal plasma positively correlated with those in cord plasma and colostrum. Our findings contribute to the existing Chinese data on gangliosides and enhance understanding of their transmission patterns from mother to offspring. This trial was registered at chictr.org.cn as ChiCTR1800015387.

Characterization of GM3 Gangliosides in Human Milk throughout Lactation: Insights from the Analysis with the Use of Reversed-Phase Liquid Chromatography Coupled to Quadrupole Time-Of-Flight Mass Spectrometry

Gangliosides are complex lipids found in human milk that play important structural and biological functions. In this study, we utilized reversed-phase liquid chromatography coupled to quadrupole time-of-flight mass spectrometry to evaluate the molecular distribution of GM3 in human milk samples collected at distinct lactation stages, ranging from colostrum to advanced lactation samples. Throughout lactation, GM3 d40:1 emerged as the most abundant GM3 species, except in colostrum, where GM3 d42:2 prevailed. The relative content of GM3 species containing very long N-fatty acyl (N-FA) substituents with >22 carbon atoms decreased, while the content of GM3 species containing 14:0, 18:0, 18:1, and 20:0 N-FA substituents increased in the later months of lactation. These findings highlight the divergence of GM3 profiles across the lactation period. Moreover, considerable interindividual variance was observed among the analyzed samples. The assessment of the GM3 profiles contributes to our understanding of the dynamic composition of human milk.

High-sensitivity qualitative and quantitative analysis of human, bovine and goat milk glycosphingolipids using HILIC-MS/MS with internal standards

Glycosphingolipids (GSLs) in human milk regulate the immune system, support intestinal maturation, and prevent gut pathogens. The structural complexity and low abundance of GSLs limits their systematic analysis. Here, we coupled the use of monosialoganglioside 1-2-amino-N-(2-aminoethyl) benzamide (GM1-AEAB) derivatives as internal standards with HILIC-MS/MS to qualitatively and quantitatively compare GSLs in human, bovine, and goat milk. One neutral glycosphingolipid (GB) and 33 gangliosides were found in human milk, of which 22 were newly detected and three were fucosylated. Five GB and 26 gangliosides were identified in bovine milk, of which 21 were newly discovered. Four GB and 33 gangliosides were detected in goat milk, 23 of them newly reported. GM1 was the main GSL in human milk; whereas disialoganglioside 3 (GD3) and monosialogangloside 3 (GM3) were dominant in bovine and goat milk, respectively; N-acetylneuraminic acid (Neu5Ac) was detected in >88 % of GSLs in bovine and goat milk. N-hydroxyacetylneuraminic acid (Neu5Gc)-modified GSLs were 3.5 times more abundant in goat than in bovine milk; whereas GSLs modified with both Neu5Ac and Neu5Gc were 3 times more abundant in bovine than in goat milk. Given the health benefits of different GSLs, these results will facilitate the development of custom-designed human milk-based infant formula.

Ganglioside analysis in body fluids by liquid-phase separation techniques hyphenated to mass spectrometry

The expression of gangliosides in central nervous system is a few times higher than in the extraneural tissue, a characteristic highlighting their major role at this level. Although in very low amounts, gangliosides are ubiquitously distributed in body fluids too, where, depending on many factors, including pathological states, their composition fluctuates, thus having diagnostic value. Ganglioside investigation in biological fluids, which, except for cerebrospinal fluid (CSF), may be sampled noninvasively, was for years impeded by the limited sensitivity of the analytical instrumentation available in glycomics. However, because the last decade has witnessed significant developments in biological mass spectrometry (MS) and the hyphenated separation techniques, marked by a major increase in sensitivity, reproducibility, and data reliability, ganglioside research started to be focused on biofluid analysis by separation techniques coupled to MS. In this context, our review presents the achievements in this emerging field of gangliosidomics, with a particular emphasis on modern liquid chromatography (LC), thin-layer chromatography, hydrophilic interaction LC, and ion mobility separation coupled to high-performance MS, as well as the results generated by these systems and allied experimental procedures in profiling and structural analysis of gangliosides in healthy or diseased body fluids, such as CSF, plasma/serum, and milk.

Joint analyses of human milk fatty acids, phospholipids, and choline in association with cognition and temperament traits during the first 6 months of life

Early dietary exposure via human milk nutrients offers a window of opportunity to support cognitive and temperament development. While several studies have focused on associations of few pre-selected human milk nutrients with cognition and temperament, it is highly plausible that human milk nutrients synergistically and jointly support cognitive and behavioral development in early life. We aimed to discern the combined associations of three major classes of human milk nutrients with cognition and temperament during the first 6 months of life when human milk is the primary source of an infant’s nutrition and explore whether there were persistent effects up to 18 months old. The Mullen Scales of Early Learning and Infant Behavior Questionnaires—Revised were used to assess cognition and temperament, respectively, of 54 exclusively/predominantly breastfed infants in the first 6 months of life, whose follow-ups were conducted at 6–9, 9–12, and 12–18 months old. Human milk samples were obtained from the mothers of the participants at less than 6 months of age and analyzed for fatty acids [total monounsaturated fatty acids, polyunsaturated fatty acid, total saturated fatty acid (TSFA), arachidonic acid (ARA), docosahexaenoic acid (DHA), ARA/DHA, omega-6/omega-3 polyunsaturated fatty acids ratio (n-6/n-3)], phospholipids [phosphatidylcholine, phosphatidylethanolamine (PE), phosphatidylinositol (PI), sphingomyelin], and choline [free choline, phosphocholine (PCho), glycerophosphocholine]. Feature selection was performed to select nutrients associated with cognition and temperament. The combined effects of selected nutrients were analyzed using multiple regression. A positive association between the arachidonic acid (ARA) and surgency was observed (p = 0.024). A significant effect of DHA, n-6/n-3, PE, and TSFA concentrations on receptive language (R² = 0.39, p = 0.025) and the elevated ARA, PCho, and PI with increased surgency (R² = 0.43, p = 0.003) was identified, suggesting that DHA and ARA may have distinct roles for temperament and language functions. Furthermore, the exploratory association analyses suggest that the effects of human milk nutrients on R.L. and surgency may persist beyond the first 6 months of life, particularly surgency at 12–18 months (p = 0.002). Our study highlighted that various human milk nutrients work together to support the development of cognition and temperament traits during early infancy.

Milk polar lipids composition and functionality: a systematic review

Polar lipids including glycerophospholipids and sphingophospholipids are important nutrients and milk is a major source, particularly for infants. This systematic review describes the human and bovine milk polar lipid composition, structural organization, sources for formulation, and physiological functionality. A total of 2840 records were retrieved through Scopus, 378 were included. Bovine milk is a good source of polar lipids, where yield and composition are highly dependent on the choice of dairy streams and processing. In milk, polar lipids are organized in the milk fat globule membrane as a tri-layer encapsulating triglyceride. The overall polar lipid concentration in human milk is dependent on many factors including lactational stage and maternal diet. Here, reasonable ranges were determined where possible. Similar for bovine milk, where differences in milk lipid concentration proved the largest factor determining variation. The role of milk polar lipids in human health has been demonstrated in several areas and critical review indicated that brain, immune and effects on lipid metabolism are best substantiated areas. Moreover, insights related to the milk fat globule membrane structure-function relation as well as superior activity of milk derived polar lipid compared to plant-derived sources are emerging areas of interest regarding future research and food innovations.

Safety and tolerance assessment of milk fat globule membrane-enriched infant formulas in healthy term Chinese infants: a randomised multicenter controlled trial

Background

Milk fat globule membrane (MFGM), natural to breast milk, is essential for neonatal development, but lacking from standard infant formulas.

Objectives

To evaluate the safety and tolerability of MFGM supplementation in formula for infants 0 to 12 months.

Methods

In a prospective, multicentre, double-blind, randomized trial, healthy term infants were randomized to a standard formula (SF, n = 104) or an MFGM-enriched formula (MF, n = 108) for 6 months and a corresponding follow-on formula until 12 months. Exclusively breast-fed infants (n = 206) were recruited as the reference group (BFR). Tolerance and safety events were recorded continuously. Anthropometric measurements were assessed at enrolment, 42 days and 4, 6, 8 and 12 months.

Results

Infants (n = 375) completed the study with average dropout of < 20%. Stool frequency, color, and consistency between SF and MF were not significantly different throughout, except the incidence of loose stools in MF at 6 months being lower than for SF (odds ratio 0.216, P < 0.05) and the frequency of green-colored stools at 12 months being higher in MF (CI 95%, odds ratio 8.92, P < 0.05). The BFR had a higher frequency of golden stools and lower rate of green stools (4–6 months) than the two formula-fed groups (P < 0.05). SF displayed more diarrhoea (4.8%) than MF (1%) and BFR (1%) at the 8-month visit (P < 0.05). BFR (0–1%) had significantly less (P < 0.05) lower respiratory infections than MF (4.6–6.5%) and SF (2.9–5.8%) at 6- and 8-months, respectively. Formula intake, frequency of spit-up/vomiting or poor sleep were similar between SF and MF. Growth rate (g/day) was similar at 4, 6, 8 and 12 months between the 3 groups, but growth rate for BFR was significantly higher than for SF and MF at 42 days (95% CI, P = 0.001).

Conclusions

MFGM-enriched formula was safe and well-tolerated in healthy term infants between 0 and 12 months, and total incidences of adverse events were similar to that for the SF group. A few differences in formula tolerance were observed, however these differences were not in any way related to poor growth.

Changes in Human Milk Fat Globule Composition Throughout Lactation: A Review

There has been a growing interest in understanding how the relative levels of human milk fat globule (MFG) components change over the course of lactation, how they differ between populations, and implications of these changes for the health of the infant. In this article, we describe studies published over the last 30 years which have investigated components of the MFG in term milk, focusing on changes over the course of lactation and highlighting infant and maternal factors that may influence these changes. We then consider how the potential health benefits of some of the milk fat globule membrane (MFGM) components and derived ingredients relate to compositional and functional aspects and how these change throughout lactation. The results show that the concentrations of phospholipids, gangliosides, cholesterol, fatty acids and proteins vary throughout lactation, and such changes are likely to reflect the changing requirements of the growing infant. There is a lack of consistent trends for changes in phospholipids and gangliosides across lactation which may reflect different methodological approaches. Other factors such as maternal diet and geographical location have been shown to influence human MFGM composition. The majority of research on the health benefits of MFGM have been conducted using MFGM ingredients derived from bovine milk, and using animal models which have clearly demonstrated the role of the MFGM in supporting cognitive and immune health of infants at different stages of growth and development.

The Potential for Sialic Acid and Sialylated Glycoconjugates as Feed Additives to Enhance Pig Health and Production

Simple Summary

This review discusses the current challenges in the pig industry and the potential nutritional significance of sialic acid (Sia) and glycoconjugates (Sia-GC’s) for pig health and nutrition. Sia is a nine-carbon acidic sugar which is present in various organs and body fluids of humans and animals. Sias contribute to many beneficial biological functions including pathogen resistance, immunomodulation, gut microbiota development, gut maturation, anti-inflammation and neurodevelopment. The role of Sias in regulating the metabolism of pigs has seldom been reported. However, we have documented significant beneficial effects of specific Sia-GC’s on health and production performance of sows and piglets. These findings are reviewed in relation to other studies while noting the beneficial effects of the inclusion of Sia, Sia containing oligosaccharide or the sialo-protein lactoferrin in the diets of gilts and sows. The importance of the passive transfer of of Sia and Sia-GC’s through milk to the young and the implications for their growth and development is also reviewed. This information will assist in optimizing the composition of sow/gilt milk replacers designed to increases the survival of IUGR piglets or piglets with dams suffering from agalactia, a common problem in pig production systems worldwide.

Abstract

Swine are one of the most important agricultural species for human food production. Given the significant disease challenges confronting commercial pig farming systems, introduction of a new feed additive that can enhance animal performance by improving growth and immune status represents a major opportunity. One such candidate is sialic acid (Sia), a diverse family of nine-carbon acidic sugar, present in various organs and body fluid, as well as an essential structural and functional constituent of brain ganglioside of humans and animals. Sias are key monosaccharide and biomarker of sialylated milk oligosaccharide (Sia-MOS’s), sialylated glycoproteins and glycolipids in milk and all vertebrate cells. Sias accomplish many critical endogenous functions by virtue of their physiochemical properties and via recognition by intrinsic receptors. Human milk sialylated glycoconjugates (Sia-GC’s) are bioactive compounds known to act as prebiotics that promote gut microbiota development, gut maturation, pathogen resistance, immunomodulation, anti-inflammation and neurodevelopment. However, the importance of Sia in pig health, especially in the growth, development, immunity of developing piglet and in pig production remains unknown. This review aims to critically discuss the current status of knowledge of the biology and nutritional role of Sia and Sia-GC’s on health of both female sow and newborn piglets.

The Impact of Dietary Sphingolipids on Intestinal Microbiota and Gastrointestinal Immune Homeostasis

The large surfaces of gastrointestinal (GI) organs are well adapted to their diverse tasks of selective nutritional uptake and defense against the external environment. To maintain a functional balance, a vast number of immune cells is located within the mucosa. A strictly regulated immune response is required to impede constant inflammation and to maintain barrier function. An increasing prevalence of GI diseases has been reported in Western societies over the past decades. This surge in GI disorders has been linked to dietary changes followed by an imbalance of the gut microbiome, leading to a chronic, low grade inflammation of the gut epithelium. To counteract the increasing health care costs associated with diseases, it is paramount to understand the mechanisms driving immuno-nutrition, the associations between nutritional compounds, the commensal gut microbiota, and the host immune response. Dietary compounds such as lipids, play a central role in GI barrier function. Bioactive sphingolipids (SLs), e.g. sphingomyelin (SM), sphingosine (Sph), ceramide (Cer), sphingosine-1- phosphate (S1P) and ceramide-1-phosphate (C1P) may derive from dietary SLs ingested through the diet. They are not only integral components of cell membranes, they additionally modulate cell trafficking and are precursors for mediators and second messenger molecules. By regulating intracellular calcium levels, cell motility, cell proliferation and apoptosis, SL metabolites have been described to influence GI immune homeostasis positively and detrimentally. Furthermore, dietary SLs are suggested to induce a shift in the gut microbiota. Modes of action range from competing with the commensal bacteria for intestinal cell attachment to prevention from pathogen invasion by regulating innate and immediate defense mechanisms. SL metabolites can also be produced by gut microorganisms, directly impacting host metabolic pathways. This review aims to summarize recent findings on SL signaling and functional variations of dietary SLs. We highlight novel insights in SL homeostasis and SL impact on GI barrier function, which is directly linked to changes of the intestinal microbiota. Knowledge gaps in current literature will be discussed to address questions relevant for understanding the pivotal role of dietary SLs on chronic, low grade inflammation and to define a balanced and healthy diet for disease prevention and treatment.

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.

Qualitative and Quantitative Study of Glycosphingolipids in Human Milk and Bovine Milk Using High Performance Liquid Chromatography-Data-Dependent Acquisition-Mass Spectrometry

Cerebrosides (Crb; including glucosylceramide and galactosylceramide) and lactosylceramide (LacCer) are structurally complex lipids found in many eukaryotic cell membranes, where they play important roles in cell growth, apoptosis, cell recognition and signaling. They are also found in mammalian milk as part of the milk fat globule membrane (MFGM), making milk an important dietary component for the rapidly growing infant. This study reports the development of a robust analytical method for the identification and characterization of 44 Crb and 23 LacCer molecular species in milk, using high performance liquid chromatography-tandem mass spectrometry in data-dependent acquisition mode. For the first time, it also compares the distributions of these species in human and bovine milks, a commercial MFGM-enriched dairy ingredient (MFGM Lipid 100) and commercial standards purified from bovine milk. A method for quantifying Crb and LacCer in milk using mass spectrometry in neutral loss scan mode was developed and validated for human milk, bovine milk and MFGM Lipid 100. Human milk was found to contain approximately 9.9-17.4 µg Crb/mL and 1.3-3.0 µg LacCer/mL, whereas bovine milk (pooled milk from a Friesian herd) contained 9.8-12.0 and 14.3-16.2 µg/mL of these lipids, respectively. The process used to produce MFGM Lipid 100 was shown to have enriched these components to 448 and 1036 µg/g, respectively. No significant changes in the concentrations of both Crb and LacCer were observed during lactation.

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.

Milk Glycans and Their Interaction with the Infant-Gut Microbiota

Human milk is a unique and complex fluid that provides infant nutrition and delivers an array of bioactive molecules that serve various functions. Glycans, abundant in milk, can be found as free oligosaccharides or as glycoconjugates. Milk glycans are increasingly linked to beneficial outcomes in neonates through protection from pathogens and modulation of the immune system. Indeed, these glycans influence the development of the infant and the infant-gut microbiota. Bifidobacterium species commonly are enriched in breastfed infants and are among a limited group of bacteria that readily consume human milk oligosaccharides (HMOs) and milk glycoconjugates. Given the importance of bifidobacteria in infant health, numerous studies have examined the molecular mechanisms they employ to consume HMOs and milk glycans, thus providing insight into this unique enrichment and shedding light on a range of translational opportunities to benefit at-risk infants.

Human Milk Oligosaccharide, Phospholipid, and Ganglioside Concentrations in Breast Milk from United Arab Emirates Mothers: Results from the MISC Cohort

Human milk oligosaccharides (HMOs), phospholipids (PLs), and gangliosides (GAs) are components of human breast milk that play important roles in the development of the rapidly growing infant. The differences in these components in human milk from the United Arab Emirates (UAE) were studied in a cross-sectional trial. High-performance liquid chromatography‒mass spectrometry was used to determine HMO, PL, and GA concentrations in transitional (5-15 days) and mature (at 6 months post-partum) breast milk of mothers of the United Arab Emirates (UAE). The results showed that the average HMO (12 species), PL (7 species), and GA (2 species) concentrations quantified in the UAE mothers' transitional milk samples were (in mg/L) 8204 ± 2389, 269 ± 89, and 21.18 ± 11.46, respectively, while in mature milk, the respective concentrations were (in mg/L) 3905 ± 1466, 220 ± 85, and 20.18 ± 9.75. The individual HMO concentrations measured in this study were all significantly higher in transitional milk than in mature milk, except for 3 fucosyllactose, which was higher in mature milk. In this study, secretor and non-secretor phenotype mothers showed no significant difference in the total HMO concentration. For the PL and GA components, changes in the individual PL and GA species distribution was observed between transitional milk and mature milk. However, the changes were within the ranges found in human milk from other regions.

Application of industrial treatments to donor human milk: influence of pasteurization treatments, storage temperature, and time on human milk gangliosides

Donor milk is the best option when mother’s own milk is unavailable. Heat treatments are applied to ensure donor milk safety. The effects of heat treatments on milk gangliosides—bioactive compounds with beneficial antibacterial, anti-inflammatory, and prebiotic roles—have not been studied. The most abundant gangliosides in non-homogenized human milk were characterized and quantified by liquid chromatography–mass spectrometry (LC–MS)/MS before and after pasteurization treatments mimicking industrial conditions (63 °C/30 min, 72 °C/15 s, 127 °C/5 s, and 140 °C/6 s). Ganglioside stability over a 3-month period was assessed following the storage at 4 and 23 °C. Independent of the heat treatment applied, gangliosides were stable after 3 months of storage at 4 or 23 °C, with only minor variations in individual ganglioside structures. These findings will help to define the ideal processing and storage conditions for donor milk to maximize the preservation of the structure of bioactive compounds to enhance the health of fragile newborns. Moreover, these results highlight the need for, and provide a basis for, a standardized language enabling biological and food companies, regulatory agencies, and other food stakeholders to both annotate and compute the ways in which production, processing, and storage conditions alter or maintain the nutritive, bioactive, and organoleptic properties of ingredients and foods, as well as the qualitative effects these foods and ingredients may have on conferring phenotype in the consuming organism.

Donor human milk, the best alternative to mother’s own milk, usually needs to be pasteurized before use out of safety concerns. Daniela Barile at University of California Davis, USA, and colleagues studied the effects of heat treatment and storage temperature and time on milk gangliosides, a class of sugar-derived compounds important for neural and brain development of newborns, among other bioactivities. They found that, while there were minor structural changes during mimicked industrial pasteurization processes, gangliosides remain stable for at least three months either in the refrigerator or at room temperature. These results may help standardize the processing protocols and storage conditions for donor milk, and the methods can be extended to other bioactive components.

Temporal Changes of Human Breast Milk Lipids of Chinese Mothers

Fatty acids (FA), phospholipids (PL), and gangliosides (GD) play a central role in infant growth, immune and inflammatory responses. The aim of this study was to determine FA, PL, and GD compositional changes in human milk (HM) during lactation in a large group of Chinese lactating mothers (540 volunteers) residing in Beijing, Guangzhou, and Suzhou. HM samples were collected after full expression from one breast and while the baby was fed on the other breast. FA were assessed by direct methylation followed by gas chromatography (GC) analysis. PL and GD were extracted using chloroform and methanol. A methodology employing liquid chromatography coupled with an evaporative light scattering detector (ELSD) and with time of flight (TOF) mass spectrometry was used to quantify PL and GD classes in HM, respectively. Saturated FA (SFA), mono-unsaturated FA (MUFA), and PL content decreased during lactation, while polyunsaturated FA (PUFA) and GD content increased. Among different cities, over the lactation time, HM from Beijing showed the highest SFA content, HM from Guangzhou the highest MUFA content and HM from Suzhou the highest n-3PUFA content. The highest total PL and GD contents were observed in HM from Suzhou. In order to investigate the influence of the diet on maternal milk composition, a careful analyses of dietary habits of these population needs to be performed in the future.

Ganglioside Composition in Beef, Chicken, Pork, and Fish Determined Using Liquid Chromatography-High-Resolution Mass Spectrometry

Gangliosides (GA) are found in animal tissues and fluids, such as blood and milk. These sialo-glycosphingolipids have bioactivities in neural development, the gastrointestinal tract, and the immune system. In this study, a high-performance liquid chromatography-mass spectrometry (HPLC-MS) method was validated to characterize and quantitate the GA in beef, chicken, pork, and fish species (turbot, snapper, king salmon, and island mackerel). For the first time, we report the concentration of GM3, the dominant GA in these foods, as ranging from 0.35 to 1.1 mg/100 g and 0.70 to 5.86 mg/100 g of meat and fish, respectively. The minor GAs measured were GD3, GD1a, GD1b, and GT1b. Molecular species distribution revealed that the GA contained long- to very-long-chain acyl fatty acids attached to the ceramide moiety. Fish GA contained only N-acetylneuraminic acid (NeuAc) sialic acid, while beef, chicken, and pork contained GD1a/b species that incorporated both NeuAc and N-glycolylneuraminic acid (NeuGc) and hydroxylated fatty acids.

Effect of Dietary Complex Lipids on the Biosynthesis of Piglet Brain Gangliosides

Gangliosides, found in mammalian milk, are known for their roles in brain development of the newborn. However, the mechanism involved in the impact of dietary gangliosides on brain metabolism is not fully understood. The impact of diets containing complex lipids rich in milk-derived ganglioside GD3 on the biosynthesis of gangliosides (assessed from the incorporation of deuterium) in the frontal lobe of a piglet model is reported. Higher levels of incorporation of deuterium was observed in the GM1 and GD1a containing stearic acid in samples from piglets fed milk containing 18.2 μg/mL of GD3 compared to that in those fed milk containing 25 μg/mL of GD3. This could suggest that the gangliosides from the diet may be used as a precursor for de novo biosynthesis of brain gangliosides or lead to the reduction of de novo biosynthesis of these gangliosides. This effect was more pronounced in the left compared to that in the right brain hemisphere.