Human Milk Oligosaccharides in the Milk of Mothers Delivering Term versus Preterm Infants

Human Milk Oligosaccharides, Growth, and Body Composition in Very Preterm Infants

Human milk oligosaccharides (HMOs) are bioactive factors that benefit neonatal health, but little is known about effects on growth in very preterm infants (<32 weeks' gestation). We aimed to quantify HMO concentrations in human milk fed to very preterm infants during the neonatal hospitalization and investigate associations of HMOs with infant size and body composition at term-equivalent age. In 82 human-milk-fed very preterm infants, we measured HMO concentrations at two time points. We measured anthropometrics and body composition with air displacement plethysmography at term-equivalent age. We calculated means of individual and total HMOs, constructed tertiles of mean HMO concentrations, and assessed differences in outcomes comparing infants in the highest and intermediate tertiles with the lowest tertile using linear mixed effects models, adjusted for potential confounders. The mean (SD) infant gestational age was 28.2 (2.2) weeks, and birthweight was 1063 (386) grams. Exposure to the highest (vs. lowest) tertile of HMO concentrations was not associated with anthropometric or body composition z-scores at term-corrected age. Exposure to the intermediate (vs. lowest) tertile of 3FL was associated with a greater head circumference z-score (0.61, 95% CI 0.15, 1.07). Overall, the results do not support that higher HMO intakes influence growth outcomes in this very preterm cohort.

More than nutrition: Therapeutic potential and mechanism of human milk oligosaccharides against necrotizing enterocolitis

Human milk is the most valuable source of nutrition for infants. The structure and function of human milk oligosaccharides (HMOs), which are key components of human milk, have long been attracting particular research interest. Several recent studies have found HMOs to be efficacious in the prevention and treatment of necrotizing enterocolitis (NEC). Additionally, they could be developed in the future as non-invasive predictive markers for NEC. Based on previous findings and the well-defined functions of HMOs, we summarize potential protective mechanisms of HMOs against neonatal NEC, which include: modulating signal receptor function, promoting intestinal epithelial cell proliferation, reducing apoptosis, restoring intestinal blood perfusion, regulating microbial prosperity, and alleviating intestinal inflammation. HMOs supplementation has been demonstrated to be protective against NEC in both animal studies and clinical observations. This calls for mass production and use of HMOs in infant formula, necessitating more research into the safety of industrially produced HMOs and the appropriate dosage in infant formula.

The Role of Diet and Nutritional Interventions for the Infant Gut Microbiome

The infant gut microbiome plays a key role in the healthy development of the human organism and appears to be influenced by dietary practices through multiple pathways. First, maternal diet during pregnancy and infant nutrition significantly influence the infant gut microbiota. Moreover, breastfeeding fosters the proliferation of beneficial bacteria, while formula feeding increases microbial diversity. The timing of introducing solid foods also influences gut microbiota composition. In preterm infants the gut microbiota development is influenced by multiple factors, including the time since birth and the intake of breast milk, and interventions such as probiotics and prebiotics supplementation show promising results in reducing morbidity and mortality in this population. These findings underscore the need for future research to understand the long-term health impacts of these interventions and for further strategies to enrich the gut microbiome of formula-fed and preterm infants.

Safety of lacto-N-fucopentaose I/2'-fucosyllactose (LNFP-I/2'-FL) mixture as a novel food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on lacto-N-fucopentaose I (LNFP-I)/2'-fucosyllactose (2'-FL) mixture as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is mainly composed of the human-identical milk oligosaccharides (HiMO) LNFP-I and 2'-FL, but it also contains d-lactose, lacto-N-tetraose, difucosyllactose, 3-fucosyllactose, LNFP-I fructose isomer, 2'-fucosyl-d-lactulose, l-fucose and 2'-fucosyl-d-lactitol, and a small fraction of other related saccharides. The NF is produced by fermentation by a genetically modified strain (Escherichia coli K-12 DH1 MDO MP2173b) of E. coli K-12 DH1 (DSM 4235). The information provided on the identity, manufacturing process, composition and specifications of the NF does not raise safety concerns. The applicant intends to add the NF in a variety of foods, including infant formula (IF) and follow-on formula, foods for infants and toddlers, foods for special medical purposes and food supplements (FS). The target population is the general population. The anticipated daily intake of LNFP-I from use in IF is similar to the estimated natural mean highest daily intake in breastfed infants. Overall, the anticipated daily intake of LNFP-I from the NF as a food ingredient at the maximum proposed use levels is unlikely to exceed the intake level of breastfed infants on a body weight basis. The intake in breastfed infants on a body weight basis is expected to be safe also for other population groups. The anticipated 2'-FL intake is generally rather low. The use of the NF in FS is not intended if other foods with added NF components or human milk (for infants and young children) are consumed on the same day. The Panel concludes that the NF, a mixture of LNFP-I and 2'-FL, is safe under the proposed conditions of use.

Human milk oligosaccharides in milk of mothers with term and preterm delivery at different lactation stage

Human milk oligosaccharides (HMOs) are structurally diverse unconjugated glycans, and play crucial roles in protecting infants from infections. Preterm birth is one of the leading causes of neonatal mortality, and preterm infants are particularly vulnerable and are in need of improved outcomes from breast-feeding due to the presence of bioactive HMOs. However, studies on specific difference in HMOs as a function of gestation time have been very limited. We established an approach to extract and analyze HMOs based on 96-well plate extraction and mass spectrometry, and determined maternal phenotypes through distinctive fragments in product-ion spectra. We enrolled 85 women delivering at different gestation times (25-41 weeks), and observed different HMOs correlating with gestation time based on 233 samples from the 85 donors. With the increase of postpartum age, we observed a regular changing trajectory of HMOs in composition and relative abundance, and found significant differences in HMOs secreted at different postpartum times. Preterm delivery induced more variations between participants with different phenotypes compared with term delivery, and more HMOs varied with postpartum age in the population of secretors. The sialylation level in mature milk decreased for women delivering preterm while such decrease was not observed for women delivering on term.

Quantitation of bioactive components in infant formulas: Milk oligosaccharides, sialic acids and corticosteroids

Human milk is considered the optimal food for infants with abundant nutrients and bioactive components, which play key roles in infant health and development. Infant formulas represent appropriate substitutes for human milk. There are many brands of infant formula with different ingredient sources and functions on the market. The present study aims to quantify important bioactive components, i.e., milk oligosaccharides (MOS), sialic acids (Sia) and corticosteroids, in different infant formulas and compare these to human milk. In total, 12 different infant formulas available on the Dutch market were analyzed in this study. The concentrations of MOS and Sia were characterized by UHPLC-FLD and LC-MS, while corticosteroids were determined using established UHPLC-MS/MS methods. Among infant formulas, 15 structures of oligosaccharides were identified, of which 2'-Fucosyllactose (2'FL), 3'-Galactosyllactose (3'GL) and 6'-Galactosyllactose (6́'GL) were found in all infant formulas. The oligosaccharide concentrations differed between milk source and brands and were 3-5 times lower than in human milk. All infant formulas contained Sia, N-acetylneuraminic acid (Neu5Ac) was dominant in bovine milk-based formulas, while N-glycolylneuraminic acid (Neu5Gc) was major in goat milk-based formula. All infant formulas contained corticosteroids, yet, at lower concentrations than human milk. Insight in concentrations of bioactive components in infant formula compared to human milk may give direction to dietary advices and/or novel formula design.

Safety of the extension of use of 2'-fucosyllactose (2'-FL) as a novel food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on the safety of the extension of use of 2'-fucosyllactose (2'-FL) as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is already authorised as ingredient in several food categories, including infant formula (IF) and follow-on formula (FOF). The applicant proposed to increase the maximum use levels of the NF in IF and FOF. EFSA estimated the anticipated daily intake of the NF from the proposed extension of use, including the already authorised conditions of use in other food categories. Additionally, a new intake estimate limited to the already authorised conditions of use of the NF was carried out following EFSA's current approach. The estimated daily intake of the NF from high consumption of IF alone at the proposed maximum use level in infants < 16 weeks of age is similar to the estimated natural highest mean daily intake of 2'-FL from human milk in breastfed infants. The estimated highest P95 daily intakes of the NF from the proposed extension of use in IF and FOF (including the authorised uses in other food categories) and from the already authorised conditions of use, are comparable and both higher than the estimated natural highest mean daily intake of 2'-FL from human milk in infants and to a lesser extent in young children. The Panel considers that the proposed extension of use of the NF in IF and FOF only marginally affects the highest P95 daily intake estimate from the authorised conditions of use, and therefore does not affect the safety of the NF. The Panel concludes that the NF, 2'-FL, is safe under the proposed conditions of use.

Safety of 2'-fucosyllactose (2'-FL) produced by a derivative strain (Escherichia coli SGR5) of E. coli W (ATCC 9637) as a Novel Food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on 2'-fucosyllactose (2'-FL) as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is mainly composed of the human-identical milk oligosaccharide (HiMO) 2'-FL, but it also contains d-lactose, l-fucose, fucosylgalactose, difucosyllactose, d-glucose and d-galactose, and a small fraction of other related saccharides. The NF is produced by fermentation by a genetically modified strain (Escherichia coli SGR5) of E. coli W (ATCC 9637). The information provided on the identity, manufacturing process, composition and specifications of the NF does not raise safety concerns. The applicant applies for the same use and use levels as already authorised for 2'-FL and included in the Union list of NFs, with the general population as target population. The Panel noted that the available intake estimate is not recent (2015) and based on a different database (2008-2010 UK data) than that used by EFSA. For this reason, the Panel decided to perform a new intake estimate according to the current EFSA approach. The Panel notes that the highest P95 daily intake of the NF from the use as food ingredient is higher than the estimated natural highest mean daily intake in breastfed infants and marginally higher in young children. The applicant also proposes to extend the use of 2'-FL in food supplements (FS) for infants at the use level of 1.2 g/day. The resulting estimated intake in infants from the proposed use in FS is within the natural intake of 2'-FL in breastfed infants. FS are not intended to be used if other foods with added 2'-FL or human milk are consumed on the same day. The Panel concludes that the NF is safe under the proposed conditions of use.

Development and validation of a versatile analytical method for absolute quantification of seven oligosaccharides in human, bovine, and goat milk

Oligosaccharides are significant in mammalian milk, where they serve as prebiotics that promote the growth of beneficial gut bacteria in infants. Comprehensive research of milk oligosaccharides requires precise and validated analytical methods for compositional studies. To address this need, the focus of our study was to develop and validate an analytical method using UPLC-MS/MS to quantify seven specific oligosaccharides found in mammalian milk. The developed and optimized method has adequate linearity, accuracy, and precision parameters. The detection (LOD) and quantification (LOQ) limits for the seven compounds ranged from 0.0018 to 0.0030 μg/mL and 0.0054-0.0063 μg/mL, respectively. The sample preparation method yielded recovery rates above 90.5 %. Furthermore, no significant matrix effect was observed. The validated method was successfully applied to human, goat, and bovine milk samples, demonstrating its proficiency in identifying variances in the concentration of oligosaccharides across different mammals. This versatile method will allow future research about factors affecting oligosaccharide composition.

Factors Influencing Neonatal Gut Microbiome and Health with a Focus on Necrotizing Enterocolitis

Maturational changes in the gut start in utero and rapidly progress after birth, with some functions becoming fully developed several months or years post birth including the acquisition of a full gut microbiome, which is made up of trillions of bacteria of thousands of species. Many factors influence the normal development of the neonatal and infantile microbiome, resulting in dysbiosis, which is associated with various interventions used for neonatal morbidities and survival. Extremely low gestational age neonates (<28 weeks' gestation) frequently experience recurring arterial oxygen desaturations, or apneas, during the first few weeks of life. Apnea, or the cessation of breathing lasting 15-20 s or more, occurs due to immature respiratory control and is commonly associated with intermittent hypoxia (IH). Chronic IH induces oxygen radical diseases of the neonate, including necrotizing enterocolitis (NEC), the most common and devastating gastrointestinal disease in preterm infants. NEC is associated with an immature intestinal structure and function and involves dysbiosis of the gut microbiome, inflammation, and necrosis of the intestinal mucosal layer. This review describes the factors that influence the neonatal gut microbiome and dysbiosis, which predispose preterm infants to NEC. Current and future management and therapies, including the avoidance of dysbiosis, the use of a human milk diet, probiotics, prebiotics, synbiotics, restricted antibiotics, and fecal transplantation, for the prevention of NEC and the promotion of a healthy gut microbiome are also reviewed. Interventions directed at boosting endogenous and/or exogenous antioxidant supplementation may not only help with prevention, but may also lessen the severity or shorten the course of the disease.

Biological Relevance of Goat Milk Oligosaccharides to Infant Health

Milk is often regarded as the gold standard for the nourishment of all mammalian offspring. The World Health Organization (WHO) recommends exclusive breastfeeding for the first 6 months of the life of the infant, followed by a slow introduction of complementary foods to the breastfeeding routine for a period of approximately 2 years, whenever this is possible ( Global Strategy for Infant and Young Child Feeding; WHO, 2003). One of the most abundant components in all mammals' milk, which is associated with important health benefits, is the oligosaccharides. The milk oligosaccharides (MOS) of humans and other mammals differ in terms of their concentration and diversity. Among those, goat milk contains more oligosaccharides (gMOS) than other domesticated dairy animals, as well as a greater range of structures. This review summarizes the biological functions of MOS found in both human and goat milk to identify the possible biological relevance of gMOS in human health and development. Based on the existing literature, seven biological functions of gMOS were identified, namely, MOS action as prebiotics, immune modulators, and pathogen traps; their modulation of intestinal cells; protective effect against necrotizing enterocolitis; improved brain development; and positive effects on stressor exposure. Overall, goat milk is a viable alternate supply of functional MOS that could be employed in a newborn formula.

Lactational and geographical variation in the concentration of six oligosaccharides in Chinese breast milk: a multicenter study over 13 months postpartum

Introduction

Understanding the variations of oligosaccharide in breast milk contribute to better study how human milk oligosaccharides (HMOs) play a role in health-promoting benefits in infants.

Methods

Six abundant HMOs, 2'-fucosyllactose (2'-FL), 3-fucosyllactose (3-FL), Lacto-N-tetraose (LNT), Lacto-N-neotetraose (LNnT), 3'-sialyllactose (3'-SL) and 6'-sialyllactose (6'-SL), in breast milk collected at 0-5 days, 10-15 days, 40-45 days, 200-240 days, and 300-400 days postpartum from six locations across China were analyzed using high-performance anion-exchange chromatography-pulsed amperometric detector.

Results

The concentration of individual HMO fluctuated dynamically during lactational stages. The median ranges of 2'-FL, 3-FL, LNT, LNnT, 3'-SL, and 6'-SL across the five lactational stages were 935-2865 mg/L, 206-1325 mg/L, 300-1473 mg/L, 32-317 mg/L, 106-228 mg/L, and 20-616 mg/L, respectively. The prominent variation was observed in the content of 6'-SL, which demonstrates a pattern of initial increase followed by a subsequent decrease. Among the five lactational stages, the transitional milk has the highest concentration, which was 31 times greater than the concentration in mature milk at 300-400 days postpartum, where the content is the lowest. Geographical location also influenced the content of HMOs. LNT and LNnT were the highest in mature milk of mothers from Lanzhou among the six sites at 40-240 days postpartum. Breast milks were categorized into two groups base on the abundance of 2'-FL (high and low). There was no significant difference in the proportions of high and low 2'-FL phenotypes among the six sites, and the percentages of high and low 2'-FL phenotypes were 79% and 21%, respectively, across all sites in China.

Discussion

This study provided a comprehensive dataset on 6 HMOs concentrations in Chinese breast milk during the extended postpartum period across a wide geographic range and stratified by high and low 2'-FL phenotypes.

Human Milk Oligosaccharide Profiles and the Secretor and Lewis Gene Status of Indonesian Lactating Mothers

Purpose

Human milk oligosaccharides (HMOs) may be genetically determined based on the secretor and Lewis status of the mother. This study aims to determine the HMO profile and the secretor and Lewis gene status of Indonesian lactating mothers.

Methods

Baseline data of 120 mother-infant pairs between 0-4 months post-partum obtained from a prospective longitudinal study was used. The concentrations of 2'-fucosyllactose (2'FL), lacto-N-fucopentaose I (LNFP I), lacto-N-tetraose (LNT), lacto-N-neotetraose (LNnT), 3'-sialyllactose (3'SL), and 6'-sialyllactose (6'SL) were measured. Genetic analysis was performed for mothers using targeted next-generation sequencing and Sanger sequencing. Wild-type AA with the rs1047781 (A385T) polymorphism was categorized as secretor positive, while heterozygous mutant AT was classified as a weak secretor. The presence of rs28362459 (T59G) heterozygous mutant AC and rs3745635 (G508A) heterozygous mutant CT genes indicated a Lewis negative status, and the absence of these genes indicated a positive status. Subsequently, breast milk was classified into various groups, namely Group 1: Secretor+Lewis+ (Se+Le+), Group 2: Secretor-Lewis+ (Se-Le+), Group 3: Secretor+Lewis- (Se+Le-), and Group 4: Secretor-Lewis- (Se-Le-). Data were analyzed using the Mann-Whitney and Kruskal-Wallis rank tests, and a p-value of 0.05 indicated statistical significance.

Results

A total of 58.3% and 41.7% of the samples had positive and weak secretor statuses, respectively. The proportion of those in Group 1 was 85%, while 15% were Group 3. The results showed that only 2'FL significantly differed according to the secretor status (p-value=0.018).

Conclusion

All Indonesian lactating mothers in this study were secretor positive, and most of them had a Lewis-positive status.

Safety of 3-fucosyllactose (3-FL) produced by a derivative strain of Escherichia coli K-12 DH1 as a novel food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on 3-fucosyllactose (3-FL) as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is mainly composed of the human-identical milk oligosaccharide (HiMO) 3-FL, but it also contains d-lactose, l-fucose, 3-fucosyllactulose and a small fraction of other related saccharides. The NF is produced by fermentation by a genetically modified strain (Escherichia coli K-12 DH1 MDO MAP1834) of E. coli K-12 DH1 (DSM 4235). The information provided on the manufacturing process, composition and specifications of the NF does not raise safety concerns. The applicant intends to add the NF to a variety of foods, including infant formula and follow-on formula, food for special medical purposes and food supplements (FS). The target population is the general population. The anticipated daily intake of 3-FL from both proposed and combined (authorised and proposed) uses at their respective maximum use levels in all population categories does not exceed the highest intake level of 3-FL from human milk in infants on a body weight basis. The intake of 3-FL in breastfed infants on a body weight basis is expected to be safe also for other population groups. The intake of other carbohydrate-type compounds structurally related to 3-FL is also considered of no safety concern. FS are not intended to be used if other foods with added 3-FL or human milk are consumed on the same day. The Panel concludes that the NF is safe under the proposed conditions of use.

Prebiotics to prevent necrotising enterocolitis in very preterm or very low birth weight infants

BACKGROUND

Dietary supplementation with prebiotic oligosaccharides to modulate the intestinal microbiome has been proposed as a strategy to reduce the risk of necrotising enterocolitis (NEC) and associated mortality and morbidity in very preterm or very low birth weight (VLBW) infants.

OBJECTIVES

To assess the benefits and harms of enteral supplementation with prebiotics (versus placebo or no treatment) for preventing NEC and associated morbidity and mortality in very preterm or VLBW infants.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, the Maternity and Infant Care database and the Cumulative Index to Nursing and Allied Health Literature (CINAHL), from the earliest records to July 2022. We searched clinical trials databases and conference proceedings, and examined the reference lists of retrieved articles.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs comparing prebiotics with placebo or no prebiotics in very preterm (< 32 weeks' gestation) or VLBW (< 1500 g) infants. The primary outcomes were NEC and all-cause mortality, and the secondary outcomes were late-onset invasive infection, duration of hospitalisation since birth, and neurodevelopmental impairment.

DATA COLLECTION AND ANALYSIS

Two review authors separately evaluated risk of bias of the trials, extracted data, and synthesised effect estimates using risk ratio (RR), risk difference (RD), and mean difference (MD), with associated 95% confidence intervals (CIs). The primary outcomes of interest were NEC and all-cause mortality; our secondary outcome measures were late-onset (> 48 hours after birth) invasive infection, duration of hospitalisation, and neurodevelopmental impairment. We used the GRADE approach to assess the level of certainty of the evidence.

MAIN RESULTS

We included seven trials in which a total of 705 infants participated. All the trials were small (mean sample size 100). Lack of clarity on methods to conceal allocation and mask caregivers or investigators were potential sources of bias in three of the trials. The studied prebiotics were fructo- and galacto-oligosaccharides, inulin, and lactulose, typically administered daily with enteral feeds during birth hospitalisation. Meta-analyses of data from seven trials (686 infants) suggest that prebiotics may result in little or no difference in NEC (RR 0.97, 95% CI 0.60 to 1.56; RD none fewer per 1000, 95% CI 50 fewer to 40 more; low-certainty evidence), all-cause mortality (RR 0.43, 95% CI 0.20 to 0.92; 40 per 1000 fewer, 95% CI 70 fewer to none fewer; low-certainty evidence), or late-onset invasive infection (RR 0.79, 95% CI 0.60 to 1.06; 50 per 1000 fewer, 95% CI 100 fewer to 10 more; low-certainty evidence) prior to hospital discharge. The certainty of this evidence is low because of concerns about the risk of bias in some trials and the imprecision of the effect size estimates. The data available from one trial provided only very low-certainty evidence about the effect of prebiotics on measures of neurodevelopmental impairment (Bayley Scales of Infant Development (BSID) Mental Development Index score < 85: RR 0.84, 95% CI 0.25 to 2.90; very low-certainty evidence; BSID Psychomotor Development Index score < 85: RR 0.24, 95% 0.03 to 2.00; very low-certainty evidence; cerebral palsy: RR 0.35, 95% CI 0.01 to 8.35; very low-certainty evidence).

AUTHORS' CONCLUSIONS

The available trial data provide low-certainty evidence about the effects of prebiotics on the risk of NEC, all-cause mortality before discharge, and invasive infection, and very low-certainty evidence about the effect on neurodevelopmental impairment for very preterm or VLBW infants. Our confidence in the effect estimates is limited; the true effects may be substantially different. Large, high-quality trials are needed to provide evidence of sufficient validity to inform policy and practice decisions.

Human Milk Oligosaccharide Profile across Lactation Stages in Israeli Women-A Prospective Observational Study

Human milk oligosaccharides (HMOs) stimulate the growth of gut commensals, prevent the adhesion of enteropathogens and modulate host immunity. The major factors influencing variations in the HMO profile are polymorphisms in the secretor (Se) or Lewis (Le) gene, which affect the activity of the enzymes fucoslytransferase 2 and 3 (FUT2 and FUT3) that lead to the formation of four major fucosylated and non-fucosylated oligosaccharides (OS). This pilot study aimed to determine the HMO profile of Israeli breastfeeding mothers of 16 term and 4 preterm infants, from a single tertiary center in the Tel Aviv area. Fifty-two human milk samples were collected from 20 mothers at three-time points: colostrum, transitional milk and mature milk. The concentrations of nine HMOs were assessed using liquid chromatography coupled with mass spectra chromatograms. Fifty-five percent of the mothers were secretors and 45% were non-secretors. Infant sex affected HMO levels depending on the maternal secretor status. Secretor mothers to boys had higher levels of FUT2-dependent OS and higher levels of disialyllacto-N-tetraose in the milk of mothers to girls, whereas non-secretor mothers to girls had higher levels of 3'-sialyllactose. In addition, the season at which the human milk samples were obtained affected the levels of some HMOs, resulting in significantly lower levels in the summer. Our findings provide novel information on the irregularity in the HMO profile among Israeli lactating women and identify several factors contributing to this variability.

Clinical NEC prevention practices drive different microbiome profiles and functional responses in the preterm intestine

Preterm infants with very low birthweight are at serious risk for necrotizing enterocolitis. To functionally analyse the principles of three successful preventive NEC regimens, we characterize fecal samples of 55 infants (<1500 g, n = 383, female = 22) longitudinally (two weeks) with respect to gut microbiome profiles (bacteria, archaea, fungi, viruses; targeted 16S rRNA gene sequencing and shotgun metagenomics), microbial function, virulence factors, antibiotic resistances and metabolic profiles, including human milk oligosaccharides (HMOs) and short-chain fatty acids (German Registry of Clinical Trials, No.: DRKS00009290). Regimens including probiotic Bifidobacterium longum subsp. infantis NCDO 2203 supplementation affect microbiome development globally, pointing toward the genomic potential to convert HMOs. Engraftment of NCDO 2203 is associated with a substantial reduction of microbiome-associated antibiotic resistance as compared to regimens using probiotic Lactobacillus rhamnosus LCR 35 or no supplementation. Crucially, the beneficial effects of Bifidobacterium longum subsp. infantis NCDO 2203 supplementation depends on simultaneous feeding with HMOs. We demonstrate that preventive regimens have the highest impact on development and maturation of the gastrointestinal microbiome, enabling the establishment of a resilient microbial ecosystem that reduces pathogenic threats in at-risk preterm infants.

Fact-based nutrition for infants and lactating mothers-The NUTRISHIELD study

Background

Human milk (HM) is the ideal source of nutrients for infants. Its composition is highly variable according to the infant's needs. When not enough own mother's milk (OMM) is available, the administration of pasteurized donor human milk (DHM) is considered a suitable alternative for preterm infants. This study protocol describes the NUTRISHIELD clinical study. The main objective of this study is to compare the % weight gain/month in preterm and term infants exclusively receiving either OMM or DHM. Other secondary aims comprise the evaluation of the influence of diet, lifestyle habits, psychological stress, and pasteurization on the milk composition, and how it modulates infant's growth, health, and development.

Methods and design

NUTRISHIELD is a prospective mother-infant birth cohort in the Spanish-Mediterranean area including three groups: preterm infants <32 weeks of gestation (i) exclusively receiving (i.e., >80% of total intake) OMM, and (ii) exclusively receiving DHM, and (iii) term infants exclusively receiving OMM, as well as their mothers. Biological samples and nutritional, clinical, and anthropometric characteristics are collected at six time points covering the period from birth and until six months of infant's age. The genotype, metabolome, and microbiota as well as the HM composition are characterized. Portable sensor prototypes for the analysis of HM and urine are benchmarked. Additionally, maternal psychosocial status is measured at the beginning of the study and at month six. Mother-infant postpartum bonding and parental stress are also examined. At six months, infant neurodevelopment scales are applied. Mother's concerns and attitudes to breastfeeding are registered through a specific questionnaire.

Discussion

NUTRISHIELD provides an in-depth longitudinal study of the mother-infant-microbiota triad combining multiple biological matrices, newly developed analytical methods, and ad-hoc designed sensor prototypes with a wide range of clinical outcome measures. Data obtained from this study will be used to train a machine-learning algorithm for providing dietary advice to lactating mothers and will be implemented in a user-friendly platform based on a combination of user-provided information and biomarker analysis. A better understanding of the factors affecting milk's composition, together with the health implications for infants plays an important role in developing improved strategies of nutraceutical management in infant care.

Clinical trial registration

https://register.clinicaltrials.gov, identifier: NCT05646940.

Safety of 6'-sialyllactose (6'-SL) sodium salt produced by derivative strains of Escherichia coli BL21 (DE3) as a novel food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on 6'-sialyllactose (6'-SL) sodium salt as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is mainly composed of the human-identical milk oligosaccharide (HiMO) 6'-SL, but it also contains d-lactose, 6'-sialyllactulose, sialic acid, N-acetyl-d-glucosamine and a small fraction of other related oligosaccharides. The NF is produced by fermentation with two genetically modified strains of Escherichia coli BL21 (DE3), the production strain and the optional degradation strain. The information provided on the identity, manufacturing process, composition and specifications of the NF does not raise safety concerns. The applicant intends to add the NF to a variety of foods, including infant formula and follow-on formula, food for special medical purposes and food supplements. The target population is the general population. In some scenarios at the maximum use levels, the estimated intakes per kg body weight were higher than the high average natural intake of 6'-SL from human milk. However, given the intrinsic nature of human milk oligosaccharides (HMOs), the wide range of intakes from human milk, and considering that infants are naturally exposed to similar amounts of these substances, the Panel considers that the consumption of the NF at the proposed conditions of use does not raise safety concerns. The intake of 6'-SL in breastfed infants on a body weight basis is also expected to be safe for other population groups. The intake of other carbohydrate-type compounds structurally related to 6'-SL is also considered of no safety concern. Food supplements are not intended to be used if other foods with added 6'-SL or human milk are consumed on the same day. The Panel concludes that the NF is safe under the proposed conditions of use.

Dynamics of human milk oligosaccharides in early lactation and relation with growth and appetitive traits of Filipino breastfed infants

Human milk oligosaccharides play a key role in the maturation of the infant gut microbiome and immune system and are hypothesized to affect growth. This study examined the temporal changes of 24 HMOs and their associations to infant growth and appetitive traits in an exploratory, prospective, observational, study of 41 Filipino mother-infant dyads. Exclusively breastfed, healthy, term infants were enrolled at 21-26 days of age (≈ 0.75 mo) and followed for 6 months. Infant growth measures and appetitive traits were collected at visit 1 (V1) (≈ 0.75 mo), V2 (≈ 1.5 mo), V3 (2.5 mo), V4 (2.75 mo), V5 (4 mo), and V6 (6 mo), while HMOs were measured at V1, V2, V3 and V5. Overall exposure to each HMO was summarized as area under the curve from baseline to 4 months of age and examined in association with each measure of growth at 6 months using linear regression adjusted for maternal age at birth, infant sex, birth weight, and mode of delivery. We saw modest associations between several HMOs and infant growth parameters. Our results suggest that specific HMOs, partly as proxy for milk groups (defined by Secretor and Lewis status), may be associated with head circumference and length, increasing their relevance especially in populations at the lower end of the WHO growth curve. We did not identify the same HMOs associated with infant appetitive traits, indicating that at least in our cohort, changes in appetite were not driving the observed associations between HMOs and growth.Clinical trial registration: NCT03387124.

Effects of Antioxidants in Human Milk on Bronchopulmonary Dysplasia Prevention and Treatment: A Review

Bronchopulmonary dysplasia (BPD) is a severe chronic lung illness that affects neonates, particularly premature infants. It has far-reaching consequences for infant health and their families due to intractable short- and long-term repercussions. Premature infant survival and long-term quality of life are severely harmed by BPD, which is characterized by alveolarization arrest and hypoplasia of pulmonary microvascular cells. BPD can be caused by various factors, with oxidative stress (OS) being the most common. Premature infants frequently require breathing support, which results in a hyperoxic environment in the developing lung and obstructs lung growth. OS can damage the lungs of infants by inducing cell death, inhibiting alveolarization, inducing inflammation, and impairing pulmonary angiogenesis. Therefore, antioxidant therapy for BPD relieves OS and lung injury in preterm newborns. Many antioxidants have been found in human milk, including superoxide dismutase, glutathione peroxidase, glutathione, vitamins, melatonin, short-chain fatty acids, and phytochemicals. Human milk oligosaccharides, milk fat globule membrane, and lactoferrin, all unique to human milk, also have antioxidant properties. Hence, human milk may help prevent OS injury and improve BPD prognosis in premature infants. In this review, we explored the role of OS in the pathophysiology of BPD and related signaling pathways. Furthermore, we examined antioxidants in human milk and how they could play a role in BPD to understand whether human milk could prevent and treat BPD.

The Complex Link and Disease Between the Gut Microbiome and the Immune System in Infants

The human gut microbiome is important for human health. The development of stable microbial communities in the gastrointestinal tract is closely related to the early growth and development of host immunity. After the birth of a baby, immune cells and the gut microbiome mature in parallel to adapt to the complex gut environment. The gut microbiome is closely linked to the immune system and influences each other. This interaction is associated with various diseases in infants and young children, such as asthma, food allergies, necrotizing colitis, obesity, and inflammatory bowel disease. Thus, the composition of the infant gut microbiome can predict the risk of disease development and progression. At the same time, the composition of the infant gut microbiome can be regulated in many ways and can be used to prevent and treat disease in infants by modulating the composition of the infant gut microbiome. The most important impacts on infant gut microbiota are maternal, including food delivery and feeding. The differences in the gut microbiota of infants reflect the maternal gut microbiota, which in turn reflects the gut microbiota of a given population, which is clinically significant.

Infant Formula With a Specific Blend of Five Human Milk Oligosaccharides Drives the Gut Microbiota Development and Improves Gut Maturation Markers: A Randomized Controlled Trial

Background

Human milk oligosaccharides (HMOs) have important biological functions for a healthy development in early life.

Objective

This study aimed to investigate gut maturation effects of an infant formula containing five HMOs (2′-fucosyllactose, 2′,3-di-fucosyllactose, lacto-N-tetraose, 3′-sialyllactose, and 6′-sialyllactose).

Methods

In a multicenter study, healthy infants (7–21 days old) were randomly assigned to a standard cow’s milk-based infant formula (control group, CG); the same formula with 1.5 g/L HMOs (test group 1, TG1); or with 2.5 g/L HMOs (test group 2, TG2). A human milk-fed group (HMG) was enrolled as a reference. Fecal samples collected at baseline (n∼150/formula group; HMG n = 60), age 3 (n∼140/formula group; HMG n = 65) and 6 (n∼115/formula group; HMG n = 60) months were analyzed for microbiome (shotgun metagenomics), metabolism, and biomarkers.

Results

At both post-baseline visits, weighted UniFrac analysis indicated different microbiota compositions in the two test groups (TGs) compared to CG (P < 0.01) with coordinates closer to that of HMG. The relative abundance of Bifidobacterium longum subsp. infantis (B. infantis) was higher in TGs vs. CG (P < 0.05; except at 6 months: TG2 vs. CG P = 0.083). Bifidobacterium abundance was higher by ∼45% in TGs vs. CG at 6-month approaching HMG. At both post-baseline visits, toxigenic Clostridioides difficile abundance was 75–85% lower in TGs vs. CG (P < 0.05) and comparable with HMG. Fecal pH was significantly lower in TGs vs. CG, and the overall organic acid profile was different in TGs vs. CG, approaching HMG. At 3 months, TGs (vs. CG) had higher secretory immunoglobulin A (sIgA) and lower alpha-1-antitrypsin (P < 0.05). At 6 months, sIgA in TG2 vs. CG remained higher (P < 0.05), and calprotectin was lower in TG1 (P < 0.05) vs. CG.

Conclusion

Infant formula with a specific blend of five HMOs supports the development of the intestinal immune system and gut barrier function and shifts the gut microbiome closer to that of breastfed infants with higher bifidobacteria, particularly B. infantis, and lower toxigenic Clostridioides difficile.

Clinical Trial Registration

[https://clinicaltrials.gov/ct2/show/], identifier [NCT03722550].

Structure and function of non-digestible carbohydrates in the gut microbiome

Together with proteins and fats, carbohydrates are one of the macronutrients in the human diet. Digestible carbohydrates, such as starch, starch-based products, sucrose, lactose, glucose and some sugar alcohols and unusual (and fairly rare) α-linked glucans, directly provide us with energy while other carbohydrates including high molecular weight polysaccharides, mainly from plant cell walls, provide us with dietary fibre. Carbohydrates which are efficiently digested in the small intestine are not available in appreciable quantities to act as substrates for gut bacteria. Some oligo- and polysaccharides, many of which are also dietary fibres, are resistant to digestion in the small intestines and enter the colon where they provide substrates for the complex bacterial ecosystem that resides there. This review will focus on these non-digestible carbohydrates (NDC) and examine their impact on the gut microbiota and their physiological impact. Of particular focus will be the potential of non-digestible carbohydrates to act as prebiotics, but the review will also evaluate direct effects of NDC on human cells and systems.

Current Advances in Structure-Function Relationships and Dose-Dependent Effects of Human Milk Oligosaccharides

HMOs (human milk oligosaccharides) are the third most important nutrient in breast milk. As complex glycans, HMOs play an important role in regulating neonatal intestinal immunity, resisting viral and bacterial infections, displaying anti-inflammatory characteristics, and promoting brain development. Although there have been some previous reports of HMOs, a detailed literature review summarizing the structure-activity relationships and dose-dependent effects of HMOs is lacking. Hence, after introducing the structures and synthetic pathways of HMOs, this review summarizes and categorizes identified structure-function relationships of HMOs. Differential mechanisms of different structural HMOs utilization by microorganisms are summarized. This review also emphasizes the recent advances in the interactions between different health benefits and the variance of dosage effect based on in vitro cell tests, animal experiments, and human intervention studies. The potential relationships between the chemical structure, the dosage selection, and the physiological properties of HMOs as functional foods are vital for further understanding of HMOs and their future applications.

Dietary Fiber to Starch Ratio Affects Bovine Milk Oligosaccharide Profiles

Background

Bovine milk oligosaccharides (BMOs) have several demonstrated and hypothesized benefits including roles in cognitive development and antipathogenic activities, making them promising ingredients for infant formulas and nutraceutical applications. BMO extraction from bovine milk is challenged by low concentrations relative to nonbioactive simple sugars like lactose. BMO abundances are known to vary with a cow's lactation stage, breed, and parity, but these characteristics are difficult to modify in existing dairy herds. In contrast, diet modification is an accessible target, and is already known to influence milk yield, lipid content, protein levels, and monosaccharide compositions.

Objectives

To determine the impact of a low starch high fiber versus a high starch low fiber diet on overall BMO profiles and individual BMO abundances in Holstein dairy cattle.

Methods

Milk samples were collected from 59 midlactation Holsteins in a crossover study featuring dietary modification with either a low starch high fiber or high starch low fiber feed. BMO profiles were evaluated by nano-LC quadrupole time-of-flight tandem MS, and differences in BMO abundances between diets were evaluated using linear mixed effects modeling.

Results

A total of 19 BMOs were identified across the sample set, including 4 large fucosylated compounds. Seven BMOs were found to have significantly more positive percent changes in yield-adjusted abundance from the pre-experiment baseline period for milk samples collected during feeding with the low starch high fiber diet compared with the high starch low fiber diet.

Conclusions

Consuming the low starch high fiber diet promoted greater overall BMO production than the high starch low fiber diet in a population of midlactation Holsteins. Additionally, this study afforded the opportunity to investigate the impact of other factors potentially influencing BMO abundances, furthering understanding of how dairy herd management practices can positively impact milk composition and support the potential use of BMOs as functional ingredients.

Sialic acid, the secret gift for the brain

The human brain grows rapidly in early life which requires adequate nutrition. Human milk provides optimal nutrition for the developing brain, and breastfeeding significantly improves the cognition development of infants. These benefits have been largely attributed to human milk oligosaccharides (HMOS), associated with sialic acid (Sia). Subsequently, sialylated HMOS present a vital source of exogenous Sia to infants. Sialic acid is a key molecule essential for proper development of gangliosides, and therefore critical in brain development and function. Recent pre-clinical studies suggest dietary supplementation with Sia or sialylated oligosaccharides enhances intelligence and cognition performance in early and later life. Furthermore, emerging evidence suggests the involvement of Sia in brain homeostasis and disbalance correlates with common pathologies such as Alzheimer's disease (AD). Therefore, this review will discuss early brain health and development and the role of Sia in this process. Additionally, studies associating breastfeeding and specific HMOS to benefits in cognitive development are critically assessed. Furthermore, the review will assess studies implying the potential role of HMOS and microbiota in brain development via the gut-brain axis. Finally, the review will summarize recent advances regarding the role of Sia in neurodegenerative disease in later life and potential roles of dietary Sia sources.

Safety of 3-fucosyllactose (3-FL) produced by a derivative strain of Escherichia coli BL21 (DE3) as a Novel Food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on 3‐fucosyllactose (3‐FL) as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is mainly composed of the human‐identical milk oligosaccharide (HiMO) 3‐FL, but it also contains d‐lactose, l‐fucose, d‐glucose and d‐galactose, and a small fraction of other related saccharides. The NF is produced by fermentation with a genetically modified strain of Escherichia coli BL21 (DE3). The information provided on the manufacturing process, composition and specifications of the NF does not raise safety concerns. The applicant intends to add the NF to a variety of foods, including infant formula and follow‐on formula, food for infants and young children, food for special medical purposes and food supplements. The target population is the general population. The anticipated daily intake of 3‐FL from both proposed and combined (authorised and proposed) uses at their respective maximum use levels in all population categories does not exceed the highest intake level of 3‐FL from human milk in infants on a body weight basis. The intake of 3‐FL in breastfed infants on a body weight basis is expected to be safe also for other population groups. The intake of other carbohydrate‐type compounds structurally related to 3‐FL is also considered of no safety concern. Food supplements are not intended to be used if other foods with added 3‐FL or human milk are consumed on the same day. The Panel concludes that the NF is safe under the proposed conditions of use.

Safety of lacto‐N‐tetraose (LNT) produced by derivative strains of Escherichia coli BL21 (DE3) as a Novel Food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on lacto‐N‐tetraose (LNT) as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is a powdered mixture mainly composed of the human‐identical milk oligosaccharide (HiMO) LNT, but it also contains d‐lactose, lacto‐N‐triose II and para‐lacto‐N‐hexaose, and a small fraction of other related saccharides. The NF is produced by fermentation with two genetically modified strains of Escherichia coli BL21 (DE3), the production strain and the optional degradation strain. The information provided on the manufacturing process, composition and specifications of the NF does not raise safety concerns. The applicant intends to add the NF to a variety of foods, including infant and follow‐on formula, food for infants and young children, food for special medical purposes and food supplements. The target population is the general population. The anticipated daily intake of LNT from the NF at the maximum proposed use levels does not exceed the intake level of naturally occurring LNT in breastfed infants on a body weight basis. The intake of LNT in breastfed infants on a body weight basis is expected to be safe also for other population groups. The intake of other carbohydrate‐type compounds structurally related to LNT is also considered of no safety concern. Food supplements are not intended to be used if other foods with added LNT or human milk are consumed on the same day. The Panel concludes that the NF is safe under the proposed conditions of use.

Safety of 3’‐sialyllactose (3’‐SL) sodium salt produced by derivative strains of Escherichia coli BL21 (DE3) as a Novel Food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on 3’‐sialyllactose (3’‐SL) sodium salt as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is mainly composed of the human‐identical milk oligosaccharide (HiMO) 3’‐SL, but it also contains d‐lactose, 3’‐sialyllactulose, sialic acid, N‐acetyl‐d‐glucosamine and a small fraction of other related oligosaccharides. The NF is produced by fermentation with two genetically modified strains of Escherichia coli BL21 (DE3), the production strain and the optional degradation strain. The information provided on the manufacturing process, composition and specifications of the NF does not raise safety concerns. The applicant intends to add the NF to a variety of foods, including infant formula and follow‐on formula, food for infants and young children, food for special medical purposes and food supplements. The target population is the general population. The anticipated daily intake of 3’‐SL from both proposed and combined (authorised and proposed) uses at their respective maximum use levels in all population categories does not exceed the highest intake level of 3’‐SL from human milk in infants on a body weight basis. The intake of 3’‐SL in breastfed infants on a body weight basis is expected to be safe also for other population groups. The intake of other carbohydrate‐type compounds structurally related to 3’‐SL is also considered of no safety concern. Food supplements are not intended to be used if other foods with added 3’‐SL or human milk are consumed on the same day. The Panel concludes that the NF is safe under the proposed conditions of use.

Human milk: From complex tailored nutrition to bioactive impact on child cognition and behavior

Human milk is a highly complex liquid food tailor-made to match an infant's needs. Beyond documented positive effects of breastfeeding on infant and maternal health, there is increasing evidence that milk constituents also impact child neurodevelopment. Non-nutrient milk bioactives would contribute to the (long-term) development of child cognition and behavior, a process termed 'Lactocrine Programming'. In this review we discuss the current state of the field on human milk composition and its links with child cognitive and behavioral development. To promote state-of-the-art methodologies and designs that facilitate data pooling and meta-analytic endeavors, we present detailed recommendations and best practices for future studies. Finally, we determine important scientific gaps that need to be filled to advance the field, and discuss innovative directions for future research. Unveiling the mechanisms underlying the links between human milk and child cognition and behavior will deepen our understanding of the broad functions of this complex liquid food, as well as provide necessary information for designing future interventions.

Weighted analysis of 2'-fucosylactose, 3-fucosyllactose, lacto-N-tetraose, 3'-sialyllactose, and 6'-sialyllactose concentrations in human milk

Over 150 human milk oligosaccharides (HMOs) have been identified and their concentrations in human milk vary depending on Secretor and Lewis blood group status, environmental and geographical factors, lactation stage, gestational period, and maternal health. Quantitation of HMOs in human milk has been the focus of numerous studies, however, comprehensive and weighted statistical analyses of their levels in human milk are lacking. Therefore, weighted means, standard deviations, medians, interquartile ranges, and 90th percentiles for 2'-fucosyllactose (2'-FL), 3-fucosyllactose (3-FL), lacto-N-tetraose (LNT), 3'-sialyllactose (3'-SL) and 6'-sialyllactose (6'-SL) were calculated using random sampling and the levels of these HMOs in human milk reported in the literature. Probability distributions of the reported levels were also constructed. Although the levels reported in the published studies varied, the weighted means for 2'-FL, 3-FL, LNT, 3'-SL, and 6'-SL were calculated to be 2.58, 0.57, 0.94, 0.28, and 0.39 g/L, respectively, which are consistent with those that have been previously determined in other systematic analyses. Likely due to the use of weighting, the 90th percentiles were greater than the 95% confidence limits that have been previously calculated. Our study therefore provides accurate and important statistical data to help support the level of appropriate HMO supplementation in infant formula.

Safety and efficacy of a probiotic-containing infant formula supplemented with 2'-fucosyllactose: a double-blind randomized controlled trial

BACKGROUND

Human milk oligosaccharides (HMOs) have important and diverse biological functions in early life. This study tested the safety and efficacy of a starter infant formula containing Limosilactobacillus (L.) reuteri DSM 17938 and supplemented with 2'-fucosyllactose (2'FL).

METHODS

Healthy infants < 14 days old (n = 289) were randomly assigned to a bovine milk-based formula containing L. reuteri DSM 17938 at 1 × 10⁷ CFU/g (control group; CG) or the same formula with added 1.0 g/L 2'FL (experimental group; EG) until 6 months of age. A non-randomized breastfed group served as reference (BF; n = 60). The primary endpoint was weight gain through 4 months of age in the formula-fed infants. Secondary endpoints included additional anthropometric measures, gastrointestinal tolerance, stooling characteristics, adverse events (AEs), fecal microbiota and metabolism, and gut immunity and health biomarkers in all feeding groups.

RESULTS

Weight gain in EG was non-inferior to CG as shown by a mean difference [95% CI] of 0.26 [-1.26, 1.79] g/day with the lower bound of the 95% CI above the non-inferiority margin (-3 g/day). Anthropometric Z-scores, parent-reported stooling characteristics, gastrointestinal symptoms and associated behaviors, and AEs were comparable between formula groups. Redundancy analysis indicated that the microbiota composition in EG was different from CG at age 2 (p = 0.050) and 3 months (p = 0.052), approaching BF. Similarly, between sample phylogenetic distance (weighted UniFrac) for BF vs EG was smaller than for BF vs CG at 3-month age (p = 0.045). At age 1 month, Clostridioides difficile counts were significantly lower in EG than CG. Bifidobacterium relative abundance in EG tracked towards that in BF. Fecal biomarkers and metabolic profile were comparable between CG and EG.

CONCLUSION

L. reuteri-containing infant formula with 2'FL supports age-appropriate growth, is well-tolerated and may play a role in shifting the gut microbial pattern towards that of breastfed infants.

TRIAL REGISTRATION

The trial was registered on ClinicalTrials.gov ( NCT03090360 ) on 24/03/2017.

Human milk oligosaccharide profiles and child atopic dermatitis up to 2 years of age: The Ulm SPATZ Health Study

BACKGROUND

Human milk oligosaccharides (HMOs) have several biological functions. Yet, very few studies have investigated the effect of HMOs on the development of allergies and even fewer on their specific associations with atopic dermatitis (AD) during early childhood.

OBJECTIVE

This study investigated whether individual HMO concentrations, measured at two time points of lactation, were associated with reported diagnosis of AD in children up to two years of age.

METHOD

Outcome data were available for HMOs measured in human milk samples collected at 6 weeks (n = 534) and 6 months (n = 356) of lactation. Associations of HMOs with AD, ascertained from parents and pediatricians at ages one and two years, were assessed in crude and adjusted logistic regression models.

RESULTS

Few associations were statistically significant at the conventional level (p < .05), for example, 6-week Lacto-N-neotetraose with 2-year AD [OR 95%CI: 0.82 (0.66, 1.00)] and 6-month 3'-sialyllactose among non-secretor mothers with 1-year AD [2.59 (1.53, 6.81)]. Importantly, accounting for multiple testing, these and all further associations were not statistically significant (all p > .0031, which is the threshold for statistical significance after correction for multiple testing).

CONCLUSION

Our findings suggest that the intake of different levels (or even absence) of the individual HMOs measured at 6 weeks and 6 months of lactation, in the current study, is not significantly associated with the development of AD in early childhood. Given the exploratory nature of our study and the limited sample size, these results should be interpreted with caution. The specific HMOs for which we show plausible associations at conventional level may warrant further research and investigation.

NMR Metabonomic Profile of Preterm Human Milk in the First Month of Lactation: From Extreme to Moderate Prematurity

Understanding the composition of human milk (HM) can provide important insights into the links between infant nutrition, health, and development. In the present work, we have longitudinally investigated the metabolome of milk from 36 women delivering preterm at different gestational ages (GA): extremely (<28 weeks GA), very (29–31 weeks GA) or moderate (32–34 weeks GA) premature. Milk samples were collected at three lactation stages: colostrum (3–6 days post-partum), transitional milk (7–15 days post-partum) and mature milk (16–26 days post-partum). Multivariate and univariate statistical data analyses were performed on the ¹H NMR metabolic profiles of specimens in relation to the degree of prematurity and lactation stage. We observed a high impact of both the mother’s phenotype and lactation time on HM metabolome composition. Furthermore, statistically significant differences, although weak, were observed in terms of GA when comparing extremely and moderately preterm milk. Overall, our study provides new insights into preterm HM metabolome composition that may help to optimize feeding of preterm newborns, and thus improve the postnatal growth and later health outcomes of these fragile patients.

Untangling human milk oligosaccharides and infant gut microbiome

The developing gut microbiome in infancy plays a key role in shaping the host immune system and metabolic state, and human milk is the main factor influencing its composition. Human milk does not only serve to feed the baby, but also to help the new-born adapt to its new environment and microbial exposures. Human milk protects the infant by providing multiple bioactive molecules, including human milk oligosaccharides (HMOs), which are the third most abundant solid component after lipids and lactose. The infant is unable to digest HMOs, so they reach the small and large intestines intact where they have many roles, including acting as prebiotics. Bifidobacterium spp. are the main, but not the only, commensals equipped with genes for HMO degradation. In this review we will outline the HMOs structures and functions, list the genes needed for their digestion, and describe the main strategies adopted by bacteria for their utilization.

Biology of human milk oligosaccharides: from Basic Science to Clinical Evidence

Human milk oligosaccharides (HMOs) have been researched by scientists for over 100 years, driven by the substantial evidence for the nutritional and health benefits of mother's milk. Yet research has truly bloomed during the last decade, thanks to the progress in biotechnology, which allowed the production of large amounts of bona fide HMOs. The availability of HMOs has been particularly crucial for the renewed interest in HMO research because of the low abundance or even absence of HMOs in farmed animal milk. This interest is reflected in the increasing number of original research publications and reviews on HMOs. Here, we provide an overview and critical discussion on structure function relations of HMOs that highlight why they are such interesting and important components of human milk. Clinical observations in breastfed infants backed by basic research from animal models provide guidance as to what physiological roles for HMOs are to be expected. From an evidence-based nutrition viewpoint, we discuss the current data supporting clinical relevance of specific HMOs based on randomized placebo controlled clinical intervention trials in formula-fed infants. This article is protected by copyright. All rights reserved.

Use of a Liquid Supplement Containing 2 Human Milk Oligosaccharides: The First Double-Blind, Randomized, Controlled Trial in Pre-term Infants

There is growing evidence supporting the benefit of human milk oligosaccharides (HMOs) on reducing risk of illnesses and improving immune function in newborn infants, but evidence in pre-term infants is lacking. This randomized, double-blind, placebo-controlled trial (NCT03607942) of pre-term infants evaluated the effects of HMO supplementation on feeding tolerance, growth, and safety in 7 neonatal units in France. Pre-term infants (27-33 weeks' gestation, birth weight <1,700 g) were randomized early after birth to receive HMO supplement (n = 43) [2'-fucosyllactose (2'FL) and lacto-N-neotetraose (LNnT) in a 10:1 ratio (0.374 g/kg body weight/day)] or an isocaloric placebo (n = 43) consisting of only glucose (0.140 g/kg/day) until discharge from the neonatal unit. Anthropometric z-scores were calculated using Fenton growth standards. Primary outcome was feeding tolerance, measured by non-inferiority (NI) in days to reach full enteral feeding (FEF) from birth in HMO vs. placebo group (NI margin = 4+ days). Mean number of days on intervention prior to FEF was 8.9 and 10.3 days in HMO and placebo, respectively. Non-inferiority in time to reach FEF in HMO (vs. placebo) was achieved [LS mean difference (95% CI) = -2.16 (-5.33, 1.00); upper bound of 95% CI < NI margin] in full analysis set and similar for per protocol. Adjusted mean time to reach FEF from birth was 2 days shorter in HMO (12.2) vs. placebo (14.3), although not statistically significant (p = 0.177). There was no difference in weight-for-age z-scores between groups throughout the FEF period until discharge. Length-for-age z-scores were higher in HMO at FEF day 14 [0.29 (0.02, 0.56), p = 0.037] and 21 [0.31 (0.02, 0.61), p = 0.037]. Head circumference-for-age z-score was higher in HMO vs. placebo at discharge [0.42 (0.12, 0.71), p = 0.007]. Occurrence of adverse events (AEs) was similar in both groups and relatively common in this population, whereas 2.3 and 14.3%, respectively, experienced investigator-confirmed, related AEs. HMO supplementation is safe and well-tolerated in pre-term infants. After 9 days of supplementation, the HMO group reached FEF 2 days earlier vs. placebo, although the difference was not statistically significant. In addition, HMO supplementation supports early postnatal growth, which may have a positive impact on long-term growth and developmental outcomes.

Studies and Application of Sialylated Milk Components on Regulating Neonatal Gut Microbiota and Health

Breast milk is rich in sialic acids (SA), which are commonly combined with milk oligosaccharides and glycoconjugates. As a functional nutrient component, SA-containing milk components have received increasing attention in recent years. Sialylated human milk oligosaccharides (HMOs) have been demonstrated to promote the growth and metabolism of beneficial gut microbiota in infants, bringing positive outcomes to intestinal health and immune function. They also exhibit antiviral and bacteriostatic activities in the intestinal mucosa of new-borns, thereby inhibiting the adhesion of pathogens to host cells. These properties play a pivotal role in regulating the intestinal microbial ecosystem and preventing the occurrence of neonatal inflammatory diseases. In addition, some recent studies also support the promoting effects of sialylated HMOs on neonatal bone and brain development. In addition to HMOs, sialylated glycoproteins and glycolipids are abundant in milk, and are also critical to neonatal health. This article reviews the current research progress in the regulation of sialylated milk oligosaccharides and glycoconjugates on neonatal gut microbiota and health.

Human milk oligosaccharide DSLNT and gut microbiome in preterm infants predicts necrotising enterocolitis

OBJECTIVE

Necrotising enterocolitis (NEC) is a devastating intestinal disease primarily affecting preterm infants. The underlying mechanisms are poorly understood: mother's own breast milk (MOM) is protective, possibly relating to human milk oligosaccharide (HMO) and infant gut microbiome interplay. We investigated the interaction between HMO profiles and infant gut microbiome development and its association with NEC.

DESIGN

We performed HMO profiling of MOM in a large cohort of infants with NEC (n=33) with matched controls (n=37). In a subset of 48 infants (14 with NEC), we also performed longitudinal metagenomic sequencing of infant stool (n=644).

RESULTS

Concentration of a single HMO, disialyllacto-N-tetraose (DSLNT), was significantly lower in MOM received by infants with NEC compared with controls. A MOM threshold level of 241 nmol/mL had a sensitivity and specificity of 0.9 for NEC. Metagenomic sequencing before NEC onset showed significantly lower relative abundance of Bifidobacterium longum and higher relative abundance of Enterobacter cloacae in infants with NEC. Longitudinal development of the microbiome was also impacted by low MOM DSLNT associated with reduced transition into preterm gut community types dominated by Bifidobacterium spp and typically observed in older infants. Random forest analysis combining HMO and metagenome data before disease accurately classified 87.5% of infants as healthy or having NEC.

CONCLUSION

These results demonstrate the importance of HMOs and gut microbiome in preterm infant health and disease. The findings offer potential targets for biomarker development, disease risk stratification and novel avenues for supplements that may prevent life-threatening disease.

The Human-Milk Oligosaccharide Profile of Lactating Women in Dhaka, Bangladesh

BACKGROUND

Human-milk oligosaccharides (HMOs) are an abundant component of human milk that have health-related effects on breastfeeding infants. Since variation in HMO composition can be explained by maternal and environmental factors, understanding the diversity in HMOs across settings and identifying context-specific factors associated with HMO abundances is important.

OBJECTIVES

The aim was to describe the HMO profile of Bangladeshi women and to estimate the effect of maternal vitamin D supplementation on HMO composition.

METHODS

In a cross-sectional analysis of data and samples from the Maternal Vitamin D for Infant Growth trial in Dhaka, Bangladesh (clinicaltrials.gov; NCT01924013), 192 participants were randomly selected including 96 from each of the placebo and highest-dose vitamin D supplementation groups. In mid-feed breast milk samples collected at a mean (±SD) postpartum age of 93 ± 7 d, absolute and relative abundances of 19 HMOs were analyzed by HPLC. "Secretors" were defined as participants with 2'fucosyllactose concentrations >350 nmol/mL. Associations between HMO concentrations and selected maternal or environmental factors were estimated by multivariable linear regression, adjusting for vitamin D group allocation and secretor status. HMO profiles of Bangladeshi women were compared with data from other international cohorts.

RESULTS

Overall, 34% (65/192) of participants were nonsecretors. Secretor status was associated with the concentrations of total HMOs and 79% (15/19) of individual HMOs. Vitamin D supplementation did not affect the total or individual concentration of any measured HMO. 3-Fucosyllactose concentration was significantly higher in breast milk samples collected in December to February compared with samples collected in March to May. HMO composition was similar to other previously reported cohorts.

CONCLUSIONS

The HMO profile of Bangladeshi women is predominantly determined by secretor status. Context-specific HMO data may improve understanding of the effects of HMOs on the infant microbiome and health and guide the development of HMO-containing interventions.

Oligodendrocyte Development and Implication in Perinatal White Matter Injury

Perinatal white matter injury (WMI) is the most common brain injury in premature infants and can lead to life-long neurological deficits such as cerebral palsy. Preterm birth is typically accompanied by inflammation and hypoxic-ischemic events. Such perinatal insults negatively impact maturation of oligodendrocytes (OLs) and cause myelination failure. At present, no treatment options are clinically available to prevent or cure WMI. Given that arrested OL maturation plays a central role in the etiology of perinatal WMI, an increased interest has emerged regarding the functional restoration of these cells as potential therapeutic strategy. Cell transplantation and promoting endogenous oligodendrocyte function are two potential options to address this major unmet need. In this review, we highlight the underlying pathophysiology of WMI with a specific focus on OL biology and their implication for the development of new therapeutic targets.

A one-year study of human milk oligosaccharide profiles in the milk of healthy UK mothers and their relationship to maternal FUT2 genotype

Human milk oligosaccharides (HMOs) are indigestible carbohydrates with prebiotic, pathogen decoy and immunomodulatory activities that are theorized to substantially impact infant health. The objective of this study was to monitor HMO concentrations over 1 year to develop a long-term longitudinal dataset. HMO concentrations in the breast milk of healthy lactating mothers of the Cambridge Baby Growth and Breastfeeding Study (CBGS-BF) were measured at birth, 2 weeks, 6 weeks, 3 months, 6 months and 12 months postpartum. HMO quantification was conducted by high-performance anion-exchange chromatography with pulsed amperometric detection using a newly validated "dilute-and-shoot" method. This technique minimizes sample losses and expedites throughput, making it particularly suitable for the analysis of large sample sets. Varying patterns of individual HMO concentrations were observed with changes in lactation timepoint and maternal secretor status, with the most prominent temporal changes occurring during the first 3 months. These data provide valuable information for the development of human milk banks in view of targeted distribution of donor milk based on infant age. Maternal FUT2 genotype was determined based on identification at single-nucleotide polymorphism rs516246 and compared with the genotype expected based on phenotypic markers in the HMO profile. Surprisingly, two mothers genotyped as secretors produced milk that displayed very low levels of 2'-fucosylated moieties. This unexpected discrepancy between genotype and phenotype suggests that differential enzyme expression may cause substantial variation in HMO profiles between genotypically similar mothers, and current genotypic methods of secretor status determination may require validation with HMO markers from milk analysis.

Comparison of Different Labeling Techniques for the LC-MS Profiling of Human Milk Oligosaccharides

Human milk oligosaccharides (HMOs) exhibit various biological activities for infants, such as serving as prebiotics, blocking pathogens, and aiding in brain development. HMOs are a complex mixture of hetero-oligosaccharides that are generally highly branched, containing multiple structural isomers and no intrinsic chromophores, presenting a challenge to both their resolution and quantitative detection. While liquid chromatography-mass spectrometry (LC-MS) has become the primary strategy for analysis of various compounds, the very polar and chromophore-free properties of native glycans hinder their separation in LC and ionization in MS. Various labeling approaches have been developed to achieve separation of glycans with higher resolution and greater sensitivity of detection. Here, we compared five commonly used labeling techniques [by 2-aminobenzamide, 2-aminopyridine, 2-aminobenzoic acid (2-AA), 2,6-diaminopyridine, and 1-phenyl-3-methyl-5-pyrazolone] for analyzing HMOs specifically under hydrophilic-interaction chromatography-mass spectrometry (HILIC-MS) conditions. The 2-AA labeling showed the most consistent deprotonated molecular ions, the enhanced sensitivity with the least structural selectivity, and the sequencing-informative tandem MS fragmentation spectra for the widest range of HMOs; therefore, this labeling technique was selected for further optimization under the porous graphitized carbon chromatography-mass spectrometry (PGC-MS) conditions. The combination strategy of 2-AA labeling and PGC-MS techniques provided online decontamination (removal of excess 2-AA, salts, and lactose) and resolute detection of many HMOs, enabling us to characterize the profiles of complicated HMO mixtures comprehensively in a simple protocol.

Human milk oligosaccharides alleviate stress-induced visceral hypersensitivity and associated microbiota dysbiosis

Pain-related functional gastrointestinal disorders (FGIDs) are characterized by visceral hypersensitivity (VHS) associated with alterations in the microbiota-gut-brain axis. Since human milk oligosaccharides (HMOs) modulate microbiota, gut and brain, we investigated whether HMOs impact VHS, and explored the role of gut microbiota. To induce VHS, C57BL/6JRj mice received hourly water avoidance stress (WAS) sessions for 10 d, or antibiotics (ATB) for 12 d. Challenged and unchallenged (Sham) animals were fed AIN93M diet (Cont) or AIN93M containing 1% of a 6-HMO mix (HMO6). VHS was assessed by monitoring the visceromotor response to colorectal distension. Fecal microbiome was analyzed by shotgun metagenomics. The effect of HMO6 sub-blends on VHS and nociceptive pathways was further tested using the WAS model. In mice fed Cont, WAS and ATB increased the visceromotor response to distension. HMO6 decreased WAS-mediated electromyographic rise at most distension volumes and overall Area Under Curve (AUC=6.12±0.50 in WAS/HMO6 vs. 9.46±0.50 in WAS/Cont; P<.0001). In contrast, VHS in ATB animals was not improved by HMO6. In WAS, HMO6 promoted most microbiota taxa and several functional pathways associated with low VHS and decreased those associated with high VHS. Among the sub-blends, 2'FL+DFL and LNT+6'SL reduced visceromotor response close to Sham/Cont values and modulated serotoninergic and CGRPα-related pathways. This research further substantiates the capacity of HMOs to modulate the microbiota-gut-brain communication and identifies mitigation of abdominal pain as a new HMO benefit. Ultimately, our findings suggest the value of specific HMO blends to alleviate pain associated FGIDs such as infantile colic or Irritable Bowel Syndrome.

Human Milk, More Than Simple Nourishment

Human breast milk not only has nutritional properties but also holds a functional role. It contains various bioactive factors (lactoferrin, lysozyme, leukocytes, immunoglobulins, cytokines, hormones, human milk oligosaccharides, microbiome, microRNAs and stem cells) shown to contribute to several short- and long-term health outcomes. Some of these factors appear to be involved in the infant's neuro-cognitive development, anti-oncogenic processes, cellular communication and differentiation. Furthermore, breast milk is increasingly recognized to have dynamic characteristics and to play a fundamental role in the cross-talking mother-neonate. This narrative review aims to provide a summary and an update on these bioactive substances, exploring their functions mainly on immunomodulation, microbiome and virome development. Although the knowledge about breast milk potentiality has significantly improved, leading to discovering unexpected functions, the exact mechanisms with which breast milk exercises its bioactivity have not been completely clarified. This can represent a fertile ground for exploring and understanding the complexity behind these functional elements to develop new therapeutic strategies.

Human milk oligosaccharides, infant growth, and adiposity over the first 4 months of lactation

BACKGROUND

The relationship between human milk oligosaccharides (HMOs) and infant growth and adiposity is not fully understood and comprehensive studies are missing from the current literature.

METHODS

We screened and recruited 370 healthy, pregnant women and their infants from seven European countries. Breastmilk samples were collected using standardized procedures at six time points over 4 months, as were infant parameters. Correlations and associations between HMO area under the curve, anthropometric data, and fat mass at 4 months were tested.

RESULTS

Lacto-N-neotetraose had a negative correlation with the change in length (rs = -0.18, P = 0.02). Sialyllacto-N-tetraose c (LSTc) had a positive correlation with weight for length (rs = 0.19, P = 0.015). Infants at the 25th upper percentile were fed milk higher in 3'-sialyllactose and LSTc (P = 0.017 and P = 0.006, respectively) compared to the lower 25th percentile of the weight-for-length z-score gain over 4 months of lactation. No significant associations between growth and body composition and Lewis or secretor-dependent HMOs like 2'-fucosyllactose were identified.

CONCLUSIONS

Changes in the HMO composition of breastmilk during the first 4 months appear to have little influence on infant growth and body composition in this cohort of healthy mothers and infants.

IMPACT

Modest associations exist between individual HMO and infant growth outcomes at least in healthy growing populations. Our study provides a comprehensive investigation of associations between all major HMO and infant growth and adiposity including several time points. Certain groups of HMOs, like the sialylated, may be associated with adiposity during the first months of lactation. HMO may modulate the risk of future metabolic disease. Future population studies need to address the role of specific groups of HMOs in the context of health and disease to understand the long-term impact.

Clinical Evaluation of 16-Week Supplementation with 5HMO-Mix in Healthy-Term Human Infants to Determine Tolerability, Safety, and Effect on Growth

Human milk oligosaccharides (HMOs) are complex sugars that occur naturally in human breast milk and provide many beneficial functions. Most formula products lack HMOs or contain only the most abundant HMO, 2′-fucosyllactose; however, benefits of HMOs come from multiple sugars. We therefore developed a mixture of five HMOs (5HMO-Mix) mimicking the natural concentrations of the top five HMOs (5.75 g/L total, comprising 52% 2′-fucosyllactose, 13% 3-fucosyllactose, 26% lacto-N-tetraose, 4% 3′-sialyllactose, and 5% 6′-sialyllactose) representing the groups of neutral, neutral-fucosylated, and sialylated HMOs. We conducted the first multicenter, randomized, controlled, parallel-group clinical study assessing the safety, tolerability, and effect on growth of formula containing the 5HMO-Mix in healthy infants. We enrolled 341 subjects aged ≤14 days; 225 were randomized into groups fed either with infant formula containing 5HMO-Mix (5HMO-Mix) or infant formula without HMOs (IF) for 4 months, with the others exclusively breastfed. There were no differences in weight, length, or head circumference gain between the two formula groups. The 5HMO-Mix was well tolerated, with 5HMO-Mix and breastfed infants producing softer stools at a higher stool frequency than the control formula group. Adverse events were equivalent in all groups. We conclude that the 5HMO-Mix at 5.75 g/L in infant formula is safe and well tolerated by healthy term infants during the first months of life.