Consumption of Different Combinations of Human Milk Oligosaccharides in the First 6 Months of Infancy is Positively Associated with Early Cognition at 2 Years of Age in a Longitudinal Cohort of Latino Children.

BACKGROUND: Lactation has been widely associated with optimal neurocognitive development, but the underlying mechanism remains unknown. Human milk oligosaccharides (HMOs) are complex sugars that support brain development, but prior studies examining their associations with cognition have yielded inconsistent findings. OBJECTIVE: To provide a broader understanding of how HMOs jointly influence cognition. METHODS: We used data from an ongoing longitudinal cohort of Latino mother-infant dyads. Human milk samples from 1-month (n = 157) and 6-months (n = 107) postpartum were assessed for the 19 most abundant HMOs. Cognitive performance was assessed at 2-years using the Bayley Scale of Infant and Toddler Development. A partial least squares model identified HMO combinations predictive of cognitive scores. RESULTS: At 1-month, the combination of higher levels of Lacto-N-neotetraose (LNnT), Lacto-N-tetraose (LNT), Lacto-N-fucopentaose III (LNFP-III), 6`Sialyllactose (6`SL), and 2`Fucosyllactose (2`FL) with lower levels of Sialyllacto-N-tetraose b (LSTb), Lacto-N-fucopentaose II (LNFP-II), Fucodisialyllacto-N-hexaose (FDSLNH), and 3-Fucosyllactose (3FL) significantly predicted higher cognitive scores (ß = 0.61 [0.30, 0.92]), explaining an additional 8% of the variance over a model with only nuisance covariates (11%). Additional analyses revealed that the combination of higher LNFP-III and lower LSTb alone explained 5% more of the variation in cognitive scores (ß = 0.66 [0.24, 1.09]). At 6-months (n = 107), higher LNnT, LNT, and LNFP-III and lower 3-fucosyllactose (3FL) and LSTb explained an extra 6% of the variance in cognitive scores (ß = 0.43 [0.12 - 0.75]). CONCLUSIONS: This study highlights specific HMO combinations in early life influencing cognitive performance at 2 years.

Maternal Diet Associated with Oligosaccharide Abundances in Human Milk from Latina Mothers.

Growing evidence indicates that human milk oligosaccharides (HMOs) are important bioactive compounds that enhance health and developmental outcomes in breastfed babies. Maternal dietary intake likely contributes to variation in HMO composition, but studies identifying diet-HMO relationships are few and inconsistent. This study aimed to investigate how the maternal intake of macronutrients and micronutrients-specifically proteins, fats, vitamins, and minerals-associated with HMOs at 1 month (n = 210), 6 months (n = 131), and 12 months postpartum (n = 84). Several associations between maternal dietary factors and HMO profiles were identified utilizing partial correlation analysis. For example, maternal free sugar (rho = -0.02, p < 0.01), added sugar (rho = -0.22, p < 0.01), and sugary sweetened beverage (rho = -0.22, p < 0.01) intake were negatively correlated with the most abundant HMO, 2'-fucosyllactose (2'-FL), at 1 month, suggesting that higher sugar consumption was associated with reduced levels of 2'-FL. Further, vitamins D, C, K, and the minerals zinc and potassium were positively correlated with 2'-FL at 1 month (pAll < 0.05). For the longitudinal analysis, a mixed-effects linear regression model revealed significant associations between maternal vitamin intake and HMO profiles over time. For example, for each unit increase in niacin intake, there was a 31.355 nmol/mL increase in 2'-FL concentration (p = 0.03). Overall, the results provide additional evidence supporting a role for maternal nutrition in shaping HMO profiles, which may inform future intervention strategies with the potential of improving infant growth and development through optimal HMO levels in mothers' milk.

Multimodal machine learning for modeling infant head circumference, mothers' milk composition, and their shared environment.

Links between human milk (HM) and infant development are poorly understood and often focus on individual HM components. Here we apply multi-modal predictive machine learning to study HM and head circumference (a proxy for brain development) among 1022 mother-infant dyads of the CHILD Cohort. We integrated HM data (19 oligosaccharides, 28 fatty acids, 3 hormones, 28 chemokines) with maternal and infant demographic, health, dietary and home environment data. Head circumference was significantly predictable at 3 and 12 months. Two of the most associated features were HM n3-polyunsaturated fatty acid C22:6n3 (docosahexaenoic acid, DHA; p = 9.6e-05) and maternal intake of fish (p = 4.1e-03), a key dietary source of DHA with established relationships to brain function. Thus, using a systems biology approach, we identified meaningful relationships between HM and brain development, which validates our statistical approach, gives credence to the novel associations we observed, and sets the foundation for further research with additional cohorts and HM analytes.

Associations between human milk oligosaccharides and infant growth in a Bangladeshi mother-infant cohort.

BACKGROUND: We aimed to estimate associations between human milk oligosaccharides (HMOs) and infant growth (length-for-age (LAZ) and weight-for-length (WLZ) z-scores) at 12 months postnatal age. METHODS: In this secondary analysis of data from a maternal vitamin D trial in Dhaka, Bangladesh (N = 192), absolute concentrations of HMOs were measured in 13 ± 1 week(s) postpartum milk samples, infant anthropometric measurements were obtained soon after birth and at 12 months postpartum, and infant feeding was classified during 6 months postpartum. Associations between individual HMOs or HMO groups and LAZ or WLZ were estimated by multivariable linear regression adjusting for infant feeding pattern, maternal secretor status, and other potential confounders. RESULTS: The concentrations of 6'sialyllactose, lacto-N-neotetraose, and the non-fucosylated non-sialylated HMOs were inversely associated with LAZ at 12 months of age, whereas the fucosylated non-sialylated HMO concentration was positively associated with LAZ at 12 months. These associations were robust in analyses restricted to infants who were primarily exclusively/predominantly fed human milk during the first 3 (or 6) months. CONCLUSIONS: Since HMOs are both positively and negatively associated with postnatal growth, there is a need for randomized trials to estimate the causal benefits and risks of exogenously administered HMOs on infant growth and other health outcomes. IMPACT: 6'sialyllactose, lacto-N-neotetraose, and the non-fucosylated non-sialylated human milk oligosaccharides (HMOs) were inversely associated with length-for-age z-scores (LAZ) at 12 months, whereas the fucosylated non-sialylated HMO concentration was positively associated with LAZ at 12 months among Bangladeshi infants. Associations between individual and grouped HMOs with infant length growth at 12 months were as strong or stronger in analyses restricted to infants who were exclusively or predominantly fed human milk up to 3 (or 6) months. Randomized trials are needed to characterize the effects of specific HMOs on infant growth, particularly in countries where postnatal linear growth faltering is common.

Residential green environments are associated with human milk oligosaccharide diversity and composition.

Increased exposure to greener environments has been suggested to lead to health benefits in children, but the associated mechanisms in early life, particularly via biological mediators such as altered maternal milk composition, remain largely unexplored. We investigated the associations between properties of the mother's residential green environment, measured as (1) greenness (Normalized Difference Vegetation index, NDVI), (2) Vegetation Cover Diversity (VCDI) and (3) Naturalness Index (NI), and human milk oligosaccharides (HMOs), known for their immune- and microbiota-related health effects on the infant (N = 795 mothers). We show that HMO diversity increases and concentrations of several individual HMOs and HMO groups change with increased VCDI and NI in residential green environments. This suggests that variation in residential green environments may influence the infant via maternal milk through modified HMO composition. The results emphasize the mediating role of breastfeeding between the residential green environments and health in early life.

Stability of Human-Milk Oligosaccharide Concentrations Over 1 Week of Lactation and Over 6 Hours Following a Standard Meal.

BACKGROUND: Our previous studies revealed that human-milk oligosaccharides (HMOs) have health benefits for nursing infants and their concentrations change dynamically over 24 mo of lactation. Yet, the extent to which HMOs vary over the short term (days) and in response to acute factors such as maternal diet is unclear. OBJECTIVE: The purpose of this study was to determine the stability of HMO concentrations over 7 d and in response to a standard meal and sugar-sweetened beverage (SSB) over 6 h. METHODS: In this ancillary study, lactating mothers were enrolled at 6 wk postpartum. Participants received in-person instructions and materials to complete procedures at home. In the 1-wk experiment (n = 11), mothers pumped a milk sample at 07:00 h for 7 consecutive days. In the 6-h experiment (n = 35), mothers pumped a milk sample after an overnight fast at 06:00 h and then consumed a standard meal plus SSB provided by the study team. Mothers pumped a milk sample every hour for 6 consecutive hours. Samples were analyzed for the 19 most abundant HMOs. Repeated-measures ANOVA was used to test changes in HMO concentrations over time, reported as F(dftime, dferror) = F value, P value. RESULTS: Concentrations of all assayed HMOs were stable over 7 consecutive days, including, for example, the most widely studied HMOs in relation to infant health: 2'-fucosyllactose (2'FL) [F(2,17) = 0.39, P = 0.65], disialyl-lacto-N-tetraose (DSLNT) [F(4, 37) = 0.60, P = 0.66], and lacto-N-neotetraose (LNnT) [F(3, 32) = 1.5, P = 0.23]. Concentrations of all assayed HMOs were stable in response to a standard meal plus SSB. For example, fasted baseline concentrations of 2'FL, DSLNT, and LNnT were 2310 ± 1620 µg/mL, 560 ± 290 µg/mL, and 630 ± 290 µg/mL, respectively, and there were no changes in 2'FL [F(4, 119) = 1.9, P = 0.13], DSLNT [F(4, 136) = 0.39, P = 0.83], and LNnT [F(4, 120) = 0.64, P = 0.63] over 6 consecutive hours. CONCLUSIONS: HMO concentrations are stable over 1 wk of lactation and are not acutely affected by a standard meal plus SSB in mothers.

Associations of Human Milk Oligosaccharides with Infant Brain Tissue Organization and Regional Blood Flow at 1 Month of Age.

Animal studies have shown that human milk oligosaccharides (HMOs) are important in early brain development, yet their roles have not been assessed in humans. The purpose of this study was to determine the associations of HMOs with MRI indices of tissue microstructure and regional cerebral blood flow (rCBF) in infants. Mother-infant pairs (N = 20) were recruited at 1 month postpartum. Milk was assayed for the concentrations of the HMOs 2'-fucosyllactose (2'FL), 3-fucosyllactose (3FL), 3'-sialyllactose (3'SL), and 6'-sialyllactose (6'SL). Diffusion and arterial spin labeling measures were acquired using a 3.0-Tesla MRI scanner. Multiple linear regression was used to assess the voxel-wise associations of HMOs with fractional anisotropy (FA), mean diffusivity (MD), and rCBF values across the brain. After adjusting for pre-pregnancy BMI, sex, birthweight, and postmenstrual age at time of scan, a higher 2'FL concentration was associated with reduced FA, increased MD, and reduced rCBF in similar locations within the cortical mantle. Higher 3FL and 3'SL concentrations were associated with increased FA, reduced MD, and increased rCBF in similar regions within the developing white matter. The concentration of 6'SL was not associated with MRI indices. Our data reveal that fucosylated and sialylated HMOs differentially associate with indices of tissue microstructure and rCBF, suggesting specific roles for 2'FL, 3FL, and 3'SL in early brain maturation.

Traditional Farming Lifestyle in Old Older Mennonites Modulates Human Milk Composition.

Background: In addition to farming exposures in childhood, maternal farming exposures provide strong protection against allergic disease in their children; however, the effect of farming lifestyle on human milk (HM) composition is unknown. Objective: This study aims to characterize the maternal immune effects of Old Order Mennonite (OOM) traditional farming lifestyle when compared with Rochester (ROC) families at higher risk for asthma and allergic diseases using HM as a proxy. Methods: HM samples collected at median 2 months of lactation from 52 OOM and 29 ROC mothers were assayed for IgA1 and IgA2 antibodies, cytokines, endotoxin, HM oligosaccharides (HMOs), and targeted fatty acid (FA) metabolites. Development of early childhood atopic diseases in children by 3 years of age was assessed. In addition to group comparisons, systems level network analysis was performed to identify communities of multiple HM factors in ROC and OOM lifestyle. Results: HM contains IgA1 and IgA2 antibodies broadly recognizing food, inhalant, and bacterial antigens. OOM HM has significantly higher levels of IgA to peanut, ovalbumin, dust mites, and Streptococcus equii as well TGF-ß2, and IFN-λ3. A strong correlation occurred between maternal antibiotic use and levels of several HMOs. Path-based analysis of HMOs shows lower activity in the path involving lactoneohexaose (LNH) in the OOM as well as higher levels of lacto-N-neotetraose (LNnT) and two long-chain FAs C-18OH (stearic acid) and C-23OH (tricosanoic acid) compared with Rochester HM. OOM and Rochester milk formed five different clusters, e.g., butyrate production was associated with Prevotellaceae, Veillonellaceae, and Micrococcaceae cluster. Development of atopic disease in early childhood was more common in Rochester and associated with lower levels of total IgA, IgA2 to dust mite, as well as of TSLP. Conclusion: Traditional, agrarian lifestyle, and antibiotic use are strong regulators of maternally derived immune and metabolic factors, which may have downstream implications for postnatal developmental programming of infant's gut microbiome and immune system.

Oligosaccharides and Microbiota in Human Milk Are Interrelated at 3 Months Postpartum in a Cohort of Women with a High Prevalence of Gestational Impaired Glucose Tolerance.

BACKGROUND: Human milk is a rich source of human milk oligosaccharides (HMOs) and bacteria. It is unclear how these components interact within the breast microenvironment. OBJECTIVES: The objectives were first, to investigate the association between maternal characteristics and HMOs, and second, to assess the association between HMOs and microbial community composition and predicted function in milk from women with high rates of gestational glucose intolerance. METHODS: This was an exploratory analysis of a previously completed prospective cohort study (NCT01405547) where milk samples (n = 107) were collected at 3 mo postpartum. Milk microbiota composition was analyzed by V4-16S ribosomal RNA gene sequencing and HMOs by rapid high-throughput HPLC. Data were stratified and analyzed by maternal secretor status phenotype and associations between HMOs and microbiota were determined using linear regression models (ɑ-diversity), Adonis (B-diversity), Poisson regression models (differential abundance), and general linear models (predicted microbial function). RESULTS: Prepregnancy BMI, race, and frequency of direct breastfeeding, but not gestational glucose intolerance, were found to be significantly associated with a number of HMOs among secretors and non-secretors. Fucosyllacto-N-hexaose was negatively associated with microbial richness (Chao1) among secretors [B-estimate (SE): -9.3 × 102 (3.4 × 102); P = 0.0082] and difucosyllacto-N-hexaose was negatively associated with microbiota diversity (Shannon index) [-1.7 (0.78); P = 0.029] among secretors. Lacto-N-neotetraose (LNnT) was associated with both microbial B-diversity (weighted UniFrac R2 = 0.040, P = 0.036) and KEGG ortholog B-diversity (Bray-Curtis R2 = 0.039, P = 0.043) in secretors. Additionally, difucosyllactose in secretors and disialyllacto-N-hexaose and LNnT in non-secretors were associated with enrichment of predicted microbial genes encoding for metabolism- and infection-related pathways (P-false discovery rate < 0.1). CONCLUSIONS: HMOs are associated with the microbial composition and predicted microbial functions in human milk at 3 mo postpartum. Further research is needed to investigate the role these relations play in maternal and infant health.

Associations Between Human Milk Oligosaccharides at 1 Month and Infant Development Throughout the First Year of Life in a Brazilian Cohort.

BACKGROUND: Human milk oligosaccharides (HMOs) are unconjugated glycans associated with infant health and development. OBJECTIVES: To investigate the associations between HMO concentrations at 1 month and infant development throughout the first year of life. METHODS: A prospective cohort of Brazilian women between 18-40 years of age and their infants was studied from baseline (between 28-35 gestational weeks) and followed at 1 (n = 73), 6 (n = 51), and 12 months (n = 45). A total of 19 HMOs were quantified by HPLC with fluorescence detection. Infant development was evaluated by the Brazilian Ages and Stages Questionnaire. A directed acyclic graph was used to define the minimally sufficient adjustment (gestational age at birth, gestational weight gain, prepregnancy BMI, maternal age, parity, and the mode of breastfeeding at 1 month). Cox regression models with HRs and Benjamini-Hochberg multiple corrections were performed to estimate associations of HMOs with the cumulative risk of inadequate development for 5 developmental domains or for ≥2 developmental domains in all women and in the subset of secretor women (defined as the presence or near absence of 2'-fucosyllactose and lacto-N-fucopentaose I). RESULTS: The multivariate models with multiple corrections revealed an inverse association between lacto-N-tetrose (LNT) and the risk of inadequate development for personal-social skills (0.06; 95% CI: 0.01-0.76) and for ≥2 developmental domains (0.06; 95% CI: 0.01-0.59). The secretor mothers analysis also showed inverse associations with slightly different results for personal-social skills (0.09; 95% CI: 0.02-0.84) and ≥2 developmental domains (0.05; 95% CI: 0.01-0.70). CONCLUSIONS: Higher concentrations of LNT HMOs in Brazilian women are associated with their infants being less likely to be at risk of inadequate development for personal-social skills or for ≥2 developmental domains during the first year of life.

Infant gut microbiome is enriched with Bifidobacterium longum ssp. infantis in Old Order Mennonites with traditional farming lifestyle.

BACKGROUND: Growing up on traditional, single-family farms is associated with protection against asthma in school age, but the mechanisms against early manifestations of atopic disease are largely unknown. We sought determine the gut microbiome and metabolome composition in rural Old Order Mennonite (OOM) infants at low risk and Rochester, NY urban/suburban infants at high risk for atopic diseases. METHODS: In a cohort of 65 OOM and 39 Rochester mother-infant pairs, 101 infant stool and 61 human milk samples were assessed by 16S rRNA gene sequencing for microbiome composition and qPCR to quantify Bifidobacterium spp. and B. longum ssp. infantis (B. infantis), a consumer of human milk oligosaccharides (HMOs). Fatty acids (FAs) were analyzed in 34 stool and human 24 milk samples. Diagnoses and symptoms of atopic diseases by 3 years of age were assessed by telephone. RESULTS: At a median age of 2 months, stool was enriched with Bifidobacteriaceae, Clostridiaceae, and Aerococcaceae in the OOM compared with Rochester infants. B. infantis was more abundant (p < .001) and prevalent, detected in 70% of OOM compared with 21% of Rochester infants (p < .001). Stool colonized with B. infantis had higher levels of lactate and several medium- to long/odd-chain FAs. In contrast, paired human milk was enriched with a distinct set of FAs including butyrate. Atopic diseases were reported in 6.5% of OOM and 35% of Rochester children (p < .001). CONCLUSION: A high rate of B. infantis colonization, similar to that seen in developing countries, is found in the OOM at low risk for atopic diseases.

Longitudinal Changes in Human Milk Oligosaccharides (HMOs) Over the Course of 24 Months of Lactation.

BACKGROUND: Human milk oligosaccharides (HMOs) are complex glycans that are highly abundant in human milk. While over 150 HMOs have been identified, it is unknown how individual HMOs change in concentration over 24 months of lactation. OBJECTIVES: To understand how HMO concentrations change over 24 months of lactation. METHODS: Breast milk samples were collected from participants in a longitudinal cohort study of Hispanic mother-infant pairs at 1, 6, 12, 18, and 24 months postpartum. Concentrations of 19 of the most abundant HMOs were measured using HPLC. Because the parent study is ongoing and not all participants have finished all time points yet, the sample sizes ranged per time point (n = 207 at 1 month; n = 109 at 6 months; n = 83 at 12 months; n = 59 at 18 months; and n = 28 at 24 months). Approximately 88% of participants were classified as HMO secretors-a genetic factor that affects concentrations of HMOs such as 2'fucosyllactose (2'FL) and lacto-N-fucopentaose I-while the remaining 12% were classified as nonsecretors. Mixed models were used to examine changes in HMO concentrations and relative abundances over the course of lactation. RESULTS: The majority of HMOs significantly decreased in concentration over the course of lactation. The exceptions were 2'FL, sialyl-lacto-N-tetraose b, and disialyl-lacto-N-tetraose, which did not change with time, and 3-fucosyllactose (3FL) and 3'-sialyllactose (3'SL), which significantly increased. The concentration of 3FL increased 10-fold, from 195 (IQR 138-415) µg/mL at 1 month to 1930 (1100-2630) µg/mL at 24 months, while 3'SL increased 2-fold, from 277 (198-377) µg/mL to 568 (448-708) µg/mL over the same time period. CONCLUSIONS: These results indicate that HMOs do not decrease in concentration uniformly across lactation. In particular, 3FL and 3'SL increased over the course of lactation in this cohort. Future studies are required to fully understand the functions of these HMOs.

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.

Maternal milk microbiota and oligosaccharides contribute to the infant gut microbiota assembly.

Breastfeeding protects against diseases, with potential mechanisms driving this being human milk oligosaccharides (HMOs) and the seeding of milk-associated bacteria in the infant gut. In a cohort of 34 mother-infant dyads we analyzed the microbiota and HMO profiles in breast milk samples and infant's feces. The microbiota in foremilk and hindmilk samples of breast milk was compositionally similar, however hindmilk had higher bacterial load and absolute abundance of oral-associated bacteria, but a lower absolute abundance of skin-associated Staphylococcus spp. The microbial communities within both milk and infant's feces changed significantly over the lactation period. On average 33% and 23% of the bacterial taxa detected in infant's feces were shared with the corresponding mother's milk at 5 and 9 months of age, respectively, with Streptococcus, Veillonella and Bifidobacterium spp. among the most frequently shared. The predominant HMOs in feces associated with the infant's fecal microbiota, and the dominating infant species B. longum ssp. infantis and B. bifidum correlated inversely with HMOs. Our results show that breast milk microbiota changes over time and within a feeding session, likely due to transfer of infant oral bacteria during breastfeeding and suggest that milk-associated bacteria and HMOs direct the assembly of the infant gut microbiota.

Human Milk Oligosaccharides and Hispanic Infant Weight Gain in the First 6 Months.

OBJECTIVE: The aim of this study was to determine whether human milk oligosaccharides (HMOs) at 1 month predicted infant weight gain at 6 months and whether associations varied by HMO secretor status. METHODS: Participants were 157 Hispanic mother-infant pairs. Human milk samples were collected at 1 month. Nineteen individual HMOs were analyzed using high-performance liquid chromatography, and secretor status was determined by the presence of 2'-fucosyllactose or lacto-N-fucopentaose (LNFP) I. Infant weight was measured at 1 and 6 months. Path analysis was used to test effects of HMO composition on infant weight gain, adjusting for maternal age, prepregnancy BMI, and infant age, sex, and birth weight. RESULTS: In the total sample, higher LNFPII predicted lower infant weight gain (g1 = -4.1, P = 0.004); this was observed in both nonsecretor (g1 = -3.0, P = 0.006) and secretor groups (g1 = -4.7, P = 0.014). In the nonsecretor group, higher lacto-N-neotetraose (g1 = 7.6, P = 0.011) and disialyllacto-N-tetraose (g1 = 14.3, P = 0.002) predicted higher infant weight gain. There were no other associations in the secretor group. CONCLUSIONS: Our data suggest that higher LNFPII in human milk may decrease obesity risk across all infants, whereas higher lacto-N-neotetraose and disialyllacto-N-tetraose may increase obesity risk in infants of nonsecretors only.

Breastmilk Feeding Practices Are Associated with the Co-Occurrence of Bacteria in Mothers' Milk and the Infant Gut: the CHILD Cohort Study.

Gut microbiota play a critical role in infant health. It is now accepted that breastmilk contains live bacteria from endogenous and exogenous sources, but it remains unclear whether these bacteria transfer to the infant gut and whether this process is influenced by breastmilk feeding practices. Here, we show that certain bacteria, including Streptococcus spp. and Veillonella dispar, co-occur in mothers' milk and their infants' stool, and co-occurrence is reduced when infants receive pumped breastmilk. The relative abundances of commonly shared species are positively correlated between breastmilk and stool. Overall, gut microbiota composition is strongly associated with breastfeeding exclusivity and duration but not breastmilk feeding mode (nursing versus pumping). Moreover, breastmilk bacteria contributed to overall gut microbiota variation to a similar extent as other modifiers of the infant microbiome, such as birth mode. These results provide evidence that breastmilk may transfer bacteria to the infant gut and influence microbiota development.

Associations between human milk oligosaccharides (HMOs) and eating behaviour in Hispanic infants at 1 and 6 months of age.

BACKGROUND: Human milk oligosaccharides (HMOs) are naturally occurring glycans in human breast milk that act as prebiotics in the infant gut. Prebiotics have been demonstrated to suppress appetite in both adults and children. Therefore, HMOs may affect infant eating behaviour. OBJECTIVE: To determine if HMOs in breast milk are associated with eating behaviour in Hispanic infants. METHODS: Cross-sectional analysis of a prospective cohort of Hispanic mother-infant dyads (1-month, n = 157; 6-months, n = 69). Breast milk samples were screened for 19 HMOs using high pressure liquid chromatography, and eating behaviour was assessed using the Baby Eating Behaviour Questionnaire (BEBQ). We conducted multiple linear regressions to examine associations between HMOs and BEBQ scores, adjusted for maternal pre-pregnancy BMI, infant sex, birthweight, delivery mode and number of breastfeedings per day. We stratified by HMO secretor status-a genetic determinant of the types of HMOs produced. RESULTS: At 1 month, LNnT (lacto-N-neotetraose; P = .04) was negatively associated with food responsiveness in the total sample, while DFLNT (difucosyllacto-N-tetrose; P = .03) and DSLNT (disialyl-LNT; P = .04) were negatively associated with food responsiveness in secretors only. At 6 months, LSTc (sialyllacto-N-tetraose c; P = .01), FLNH (fucosyllacto-N-hexaose; P = .03), LNH (lacto-N-hexaose; P = .006) and DSLNH (disialyllacto-N-hexaose; P = .05) were positively associated with food responsiveness in both the total sample and secretors only. CONCLUSIONS: We found several HMOs that were both positively and negatively associated with infant food responsiveness, which is a measure of drive to eat.

Human milk oligosaccharides and their association with late-onset neonatal sepsis in Peruvian very-low-birth-weight infants.

BACKGROUND: Oligosaccharides are the third most abundant component in human milk. They are a potential protective agent against neonatal sepsis. OBJECTIVES: We aimed to explore the association between human milk oligosaccharides (HMOs) and late-onset sepsis in very-low-birth-weight infants, and to describe the composition and characteristics of HMOs in Peruvian mothers of these infants. METHODS: This is a secondary data analysis of a randomized clinical trial. We conducted a retrospective cohort study of mothers and their very-low-birth-weight (<1500 g) infants with ≥1 milk sample and follow-up data for >30 d. HMOs were measured by high performance liquid chromatography (HPLC). We used factor analysis and the Mantel-Cox test to explore the association between HMOs and late-onset neonatal sepsis. RESULTS: We included 153 mother-infant pairs and 208 milk samples. Overall, the frequency of the secretor phenotype was 93%. Secretors and nonsecretors were defined by the presence and near-absence of α1-2-fucosylated HMOs, respectively. The most abundant oligosaccharides were 2'-fucosyllactose, lacto-N-fucopentaose (LNFP) I, and difucosyllacto-N-tetraose in secretors and lacto-N-tetraose and LNFP II in nonsecretors. Secretors had higher amounts of total oligosaccharides than nonsecretors (11.45 g/L; IQR: 0.773 g/L compared with 8.04 g/L; IQR: 0.449 g/L). Mature milk samples were more diverse in terms of HMOs than colostrum (Simpson's Reciprocal Diversity Index). We found an association of factor 3 in colostrum with a reduced risk of late-onset sepsis (HR: 0.63; 95% CI: 0.41, 0.97). Fucosyl-disialyllacto-N-hexose (FDSLNH) was the only oligosaccharide correlated to factor 3. CONCLUSIONS: These findings suggest that concentrations of different HMOs vary from one individual to another according to their lactation period and secretor status. We also found that FDSLNH might protect infants with very low birth weight from late-onset neonatal sepsis. Confirming this association could prove 1 more mechanism by which human milk protects infants against infections and open the door to clinical applications of HMOs.This trial was registered at clinicaltrials.gov as NCT01525316.

Investigating bifidobacteria and human milk oligosaccharide composition of lactating mothers.

Human milk is known to carry its own microbiota, of which the precise origin remains obscure. Breastfeeding allows mother-to-baby transmission of microorganisms as well as the transfer of many other milk components, such as human milk oligosaccharides (HMOs), which act as metabolizable substrates for particular bacteria, such as bifidobacteria, residing in infant intestinal tract. In the current study, we report the HMO composition of 249 human milk samples, in 163 of which we quantified the abundance of members of the Bifidobacterium genus using a combination of metagenomic and flow cytometric approaches. Metagenomic data allowed us to identify four clusters dominated by Bifidobacterium adolescentis and Bifidobacterium pseudolongum, Bifidobacterium crudilactis or Bifidobacterium dentium, as well as a cluster represented by a heterogeneous mix of bifidobacterial species such as Bifidobacterium breve and Bifidobacterium longum. Furthermore, in vitro growth assays on HMOs coupled with in silico glycobiome analyses allowed us to elucidate that members of the Bifidobacterium bifidum and B. breve species exhibit the greatest ability to degrade and grow on HMOs. Altogether, these findings indicate that the bifidobacterial component of the human milk microbiota is not strictly correlated with their ability to metabolize HMOs.

Human Milk Oligosaccharide Profile Variation Throughout Postpartum in Healthy Women in a Brazilian Cohort.

Human milk oligosaccharide (HMO) composition varies throughout lactation and can be influenced by maternal characteristics. This study describes HMO variation up to three months postpartum and explores the influences of maternal sociodemographic and anthropometric characteristics in a Brazilian prospective cohort. We followed 101 subjects from 28-35 gestational weeks (baseline) and throughout lactation at 2-8 (visit 1), 28-50 (visit 2) and 88-119 days postpartum (visit 3). Milk samples were collected at visits 1, 2 and 3, and 19 HMOs were quantified usinghigh-performance liquid chromatography with fluorescence detection (HPLC-FL). Friedman post-hoc test, Spearman rank correlation for maternal characteristics and HMOs and non-negative matrix factorization (NMF) were used to define the HMO profile. Most women were secretors (89.1%) and presented high proportion of 2'-fucosyllactose (2ꞌFL) at all three sample times, while lacto-N-tetraose (LNT, 2-8 days) and lacto-N-fucopentaose II (LNFPII, 28-50 and 88-119 days) were the most abundant HMOs in non-secretor women. Over the course of lactation, total HMO weight concentrations (g/L) decreased, but total HMO molar concentrations (mmol/L) increased, highlighting differential changes in HMO composition over time. In addition, maternal pre-pregnancy body mass index (BMI) and parity influence the HMO composition in healthy women in this Brazilian cohort.