Human Milk Samples Research Articles

Human milk 3’-Sialyllactose is positively associated with language development during infancy

ABSTRACTBackgroundGenetic polymorphisms leading to variations in human milk oligosaccharide (HMO) composition have been reported. Alpha-Tetrasaccharide (A-tetra), an HMO, has been shown to only be present (>limit of detection; A-tetra+) in the human milk (HM) of women with blood type A, suggesting genetic origins determining the presence or absence (A-tetra-) of A-tetra in HM.ObjectivesThis study aimed to determine whether associations exist between HMO concentrations and cognitive development, and whether the associations vary between A-tetra+ and A-tetra- groups in children (<25 months old).MethodsWe enrolled typically developing children (2–25 months old; mean, 10 months old) who were at least partially breastfed at the study visit. The Mullen Scales of Early Learning (MSEL) were used as the primary outcome measure to assess early cognitive development. Linear mixed effects models were employed by stratifying children based on A-tetra levels (A-tetra+ or A-tetra-) to assess associations between age-removed HMO concentrations and both MSEL composite scores and the 5 subdomain scores.ResultsA total of 99 mother-child dyads and 183 HM samples were included (A-tetra+: 57 samples, 33 dyads; A-tetra-: 126 samples, 66 dyads). No significant association was observed between HMOs and MSEL when all samples were analyzed together. The composite score and 3’-sialyllactose (3’-SL) levels were positively associated [P = 0.002; effect size (EF), 13.12; 95% CI, 5.36–20.80] in the A-tetra + group. This association was driven by the receptive (adjusted P = 0.015; EF, 9.95; 95% CI, 3.91–15.99) and expressive (adjusted P = 0.048; EF, 7.53; 95% CI, 2.51–13.79) language subdomain scores. Furthermore, there was an interaction between 3’-SL and age for receptive language (adjusted P = 0.03; EF, -14.93; 95% CI, -25.29 to -4.24).ConclusionsOur study reports the association of 3’-SL and cognition, particularly language functions, in typically developing children who received HM containing detectable A-tetra during infancy.

Use of a Portable Point-of-Care Instrumentation to Measure Human Milk Sodium and Potassium Concentrations.

Objective: Human milk (HM) sodium (Na) and potassium (K) concentrations, as well as the Na and K ratio (Na:K), are associated with stages of lactation and breast health. Portable point-of-care instruments to measure HM biomarkers related to secretory activation or tight junction disturbances would supply clinicians immediate information for individualized lactation care. This study compared HM concentrations of Na and K and Na:K measured by a biochemist with inductively coupled plasma optical emission spectrometry (ICP-OES) and measured by a clinician with ion-selective electrode probes (ISEPs). Design: HM samples (n = 92) were participant collected and donated on day 10 postpartum through a convenience sample of breastfeeding women in West Michigan. Na and K concentrations were determined using ICP-OES and ISEPs. Bland-Altman plots, paired sample t-test, and logistic regressions were completed using R 3.4.4 and R Studio 1.2.1335 with package Lattice. Results: Na concentrations were not significantly different with ICP-OES (13.0 ± 14.8 mM) and ISEPs (12.6 ± 13.7 mM, p = 0.06), whereas K concentrations (ICP-OES 16.1 ± 1.9 mM, ISEPs 14.4 ± 2.4 mM, p < 0.001) and Na:K (ICP-OES 0.81 ± 0.92, ISEPs 1.01 ± 1.62, p = 0.011) were significantly different. Between both methods, the Na, K, and Na: K linear relationships were statistically significant. Conclusion: With additional longitudinal and clinical usefulness research clinicians could use ISEPs to collect and interpret relevant lactation data to support individualized lactation interventions.

Human milk imparts higher insulin concentration in infants born to women with type 2 diabetes mellitus

Objective Human milk (HM) insulin plays many roles for the infant, especially for the newborn. We hypothesized HM insulin in women with type 2 diabetes (T2DM) would be higher than BMI-matched women with either gestational diabetes (GDM) or normal glucose tolerance (NGT). In T2DM, we also assessed macronutrient composition and relationships between maternal glycemic control and HM insulin. Study design HM was characterized at 2-weeks postpartum among three BMI-matched groups: T2DM (n= 12), diet-controlled GDM (n= 12), and NGT (n= 12). In T2DM, additional fasting and postprandial HM samples were collected while wearing a continuous glucose monitor (CGM), as well as fasting and 90-minute postprandial samples after a standardized meal at 1–2 weeks postpartum. Results Fasting HM insulin was two times higher in T2DM compared to GDM and NGT (p < .001), which were not different from each other. Among T2DM, fasting (p < .001) and postprandial (p = .01) HM insulin levels were between 2 and 5× higher than plasma. Postprandial HM insulin (p = .03) and glucose (p < .001) were increased compared to fasting. Mean nocturnal glucose (p < .01) and maternal hemoglobin A1c (p < .01) positively associated with fasting HM insulin. Conclusions These data are the first to show HM insulin concentrations are doubled in T2DM compared to BMI-matched GDM and NGT. In HM of T2DM, insulin increases postprandially, may be concentrated relative to plasma, and is influenced by maternal glycemic control, with potential clinical implications that merit further study.

Human Milk Antibodies Against SARS-CoV-2: A Longitudinal Follow-Up Study.

Human milk contains antibodies against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) following Coronavirus Disease 2019 (COVID-19). These antibodies may serve as protection against COVID-19 in infants. However, the evolution of these human milk antibodies over time is unclear. To elucidate the evolution of immunoglobulin A (IgA) against SARS-CoV-2 in human milk after a SARS-CoV-2 infection. This longitudinal follow-up study included lactating mothers (N = 24) who had participated in the COVID MILK study. To assess the evolution of SARS-CoV-2 antibodies, serum and human milk samples were collected 14-143 days after the onset of clinical symptoms related to COVID-19. Enzyme-Linked ImmunoSorbent Assay was used to detect antibodies against the ectodomain of the SARS-CoV-2 spike protein. SARS-CoV-2 antibodies remain present up to 5 months (143 days) in human milk after onset of COVID-19 symptoms. Overall, SARS-CoV-2 IgA in human milk seems to gradually decrease over time. Human milk from SARS-CoV-2 convalescent lactating mothers contains specific IgA antibodies against SARS-CoV-2 spike protein up to at least 5 months post-infection. Passive viral immunity can be transferred via human milk and may serve as protection for infants against COVID-19.

Analysis of the composition and antioxidant status of breast milk in women giving birth prematurely and on time.

BackgroundBreastfeeding with mother’s milk is the best form of nutrition not only for newborn babies, but especially for premature babies, due to the health benefits of taking human food.ObjectivesThe aim of the study was to examine the basic composition, cortisol concentration and antioxidant status of breast milk samples from women giving birth before 37 weeks of pregnancy and comparing it with milk samples from women giving birth after 37 weeks of pregnancy.MethodsThe material for the study was milk taken from women giving birth before and after 37 weeks of pregnancy. The basic composition of breast milk was determined using a MIRIS analyzer, cortisol concentration in samples by an enzyme-linked immunosorbent test and their total antioxidant status was assessed by DPPH and FRAP methods.ResultsIt has been shown that the concentration of cortisol in samples of human milk in the group of women giving birth before 37 weeks was 13.95 ng / ml [4,71–86,84], while in the group of women giving birth after week 37 of pregnancy—10.31 ng / ml [2.35-39-02] (p = 0.014), while% inhibition of DPPH was 65.46% and 58.30%, respectively (p = 0.014).ConclusionsMilk from women giving birth prematurely is qualitatively different from the milk of women giving birth on time. The total antioxidant status of preterm milk is higher than term milk, which promotes the development of premature babies. Higher cortisol levels in samples from women giving birth before 37 weeks of pregnancy may stimulate the digestive system.

Estudio de calidad de la pasteurización Holder de leche materna donada en una unidad de nutrición personalizada neonatal

ObjectiveHolder pasteurization is the technique used most frequently in milk banks to minimize the risk of transmission of infectious agents. Different pasteurization devices have been described that generally use hot water or air as heat sources. In our study, we analysed the quality of pasteurization achieved with a new automated water-free pasteurizer in a neonatal personalized nutrition unit in which donated milk from mothers of infants delivered at different gestational ages and of different postnatal ages is pasteurized. Material and methodsWe analysed the temperatures of different phases of pasteurization with 8 external probes distributed evenly throughout the pasteurizer. We applied the optimal range criteria established by the European Milk Bank Association (EMBA) to assess the quality of pasteurization. We also analysed the macronutrient composition of 8 samples of donor human milk of different volumes before and after automated pasteurization. ResultsWe did not find no significant differences in the following parameters under study: time from 58°C to 62.5°C, duration of plateau, highest temperature during plateau and length of exposure to temperatures over 58°C. The macronutrient analysis showed significant changes in fat content but not in protein or lactose content. ConclusionsHolder pasteurization of human milk with a water-free pasteurizer met the quality standards recommended by the European Milk Bank Association independently of the quantity of milk pasteurized in each bottle and with significant changes in the fat content but not in the protein or lactose content.

Potential sex differences in human milk leptin and their association with asthma and wheeze phenotypes: Results of the Ulm Birth Cohorts.

The hormone leptin has been suggested to play a role in the respiratory and immune systems. Evidence on sex-specific concentrations of leptin in human milk and sex-specific associations with the development of asthma and wheeze has been put forward but is still scarce. To investigate whether male and female infants receive different levels of leptin through human milk and whether leptin is implicated in the development of asthma and wheeze in a sex-dependent manner using data from the two Ulm Birth Cohort studies. Leptin data were available from human milk samples collected at 6weeks (Ulm Birth Cohort Study [UBCS, n=678; Ulm SPATZ Health Study, n=587]), and, in SPATZ only, at 6months (n=377) and 12months (n=66) of lactation. Sex-specific associations with doctor-diagnosed asthma and wheeze phenotypes were assessed in crude and adjusted models using logistic regression. Adjustments were made for maternal allergy, exclusive breastfeeding, infant age at the time of milk sampling, and child BMI z-score. At 6weeks, leptin levels (median [min, max], in ng/L) were higher in the milk for girls (197 [0.100, 4120]) than in milk for boys (159 [1.02, 3280], p=.045) in UBCS. No significant sex differences were observed in SPATZ (p=.152). There were no significant associations of leptin with asthma or wheeze in both studies, even in a sex-dependent manner (p>.05). It remains unclear whether male and female infants receive different levels of leptin through human milk. However, leptin in human milk may not be associated with history and development of asthma and wheeze in a sex-specific manner.

Bacterial Diversity of Breast Milk in Healthy Spanish Women: Evolution from Birth to Five Years Postpartum.

The objective of this work was to characterize the microbiota of breast milk in healthy Spanish mothers and to investigate the effects of lactation time on its diversity. A total of ninety-nine human milk samples were collected from healthy Spanish women and were assessed by means of next-generation sequencing of 16S rRNA amplicons and by qPCR. Firmicutes was the most abundant phylum, followed by Bacteroidetes, Actinobacteria, and Proteobacteria. Accordingly, Streptococcus was the most abundant genus. Lactation time showed a strong influence in milk microbiota, positively correlating with Actinobacteria and Bacteroidetes, while Firmicutes was relatively constant over lactation. 16S rRNA amplicon sequencing showed that the highest alpha-diversity was found in samples of prolonged lactation, along with wider differences between individuals. As for milk nutrients, calcium, magnesium, and selenium levels were potentially associated with Streptococcus and Staphylococcus abundance. Additionally, Proteobacteria was positively correlated with docosahexaenoic acid (DHA) levels in breast milk, and Staphylococcus with conjugated linoleic acid. Conversely, Streptococcus and trans-palmitoleic acid showed a negative association. Other factors such as maternal body mass index or diet also showed an influence on the structure of these microbial communities. Overall, human milk in Spanish mothers appeared to be a complex niche shaped by host factors and by its own nutrients, increasing in diversity over time.

Legacy brominated flame retardants in human milk from the general population in Beijing, China: Biomonitoring, temporal trends from 2011 to 2018, and nursing infant's exposure assessment

Three kinds of legacy brominated flame retardants (BFRs), including eight polybrominated diphenyl ether (PBDE) congeners, tetrabromobisphenol A (TBBPA), and three hexabromocyclododecane (HBCDD) isomers, were analyzed in 105 human milk samples collected in 2018 from Beijing, China. The tested BFRs all showed high detection frequencies, and HBCDD was the most abundant BFR, with a median level of 7.64 × 103 pg/g lipid, followed by BDE-153 (389 pg/g lipid), BDE-209 (283 pg/g lipid), and TBBPA (271 pg/g lipid). By comparing the results of the present study with those of our previous Beijing human milk surveys conducted in 2014 and 2011, the contamination of TBBPA and HBCDD increased steadily from 2011 to 2018, whereas that of PBDEs decreased sharply during this period. Our results suggested that the production and consumption of BFRs in China have shifted from PBDEs to other FRs. Education level and the consumption of animal-derived foods such as eggs and meat were identified as major influencing factors for some BFRs. For nursing infants, the median levels of lower bound BFR daily intake via human milk ingestion ranged from 4.62 × 10−2 ng/kg bw/day for BDE-154 to 30.6 ng/kg bw/day for HBCDD. The daily intake of most BFRs by breastfeeding is unlikely to pose significant health risks for Beijing nursing infants. However, the minimum margin of exposure (MOE) of HBCDD was below its threshold value, which indicated that its daily intake might raise health concerns for some breastfed infants.

Comprehensive Human Milk Patterns Are Related to Infant Growth and Allergy in the CHMP Study.

The aim of the present study is to identify human milk pattern using multi-omics datasets and to explore association between patterns, infant growth, and allergy using data from the Chinese Human Milk Project (CHMP) study. Three patterns are identified from integrative analysis of proteome, lipidome, and glycome profiles of 143 mature human milk samples. Factor 1 is positively associated with 128 proteins, phospholipids, and human milk oligosaccharides (HMOs) including lacto N-neohexaose (LNnH) and lacto-N-difucohexaose II (LNDFH II); factor 2 is negatively associated with as1 -casein, phospholipids while positively associates with HMOs including LNnH, lactosialyl tetrasaccharide c (LSTc), and 2'-fucosyllactose (2'FL); factor 3 is positively associated with lysophospholipids while negatively associates with 27 proteins, triglycerides with two saturated fatty acids, 6'-sialyllactose (6'SL) and 2'FL. In general, factor 1 and factor 2 are associated with slower while factor 3 is associated with faster growth rate (p <0.044). One unit higher in loadings of factor 2 is associated with 34% lower risk of allergies (p ≤ 0.017). Associations are not significant after adjustment for city except for factor 1. Three possible human milk patterns with varying degree of stability are identified. Future work is needed to understand these patterns in terms of generalization, biologic mechanisms, and genotype influences.

COVID-19 Vaccine mRNABNT162b2 Elicits Human Antibody Response in Milk of Breastfeeding Women.

Objective: The objective of this research is to demonstrate the release of SARS-CoV-2 Spike (S) antibodies in human milk samples obtained by patients who have been vaccinated with mRNABNT162b2 vaccine. Methods: Milk and serum samples were collected in 10 volunteers 20 days after the first dose and 7 seven days after the second dose of the mRNABNT162b2 vaccine. Anti-SARS-CoV-2 S antibodies were measured by the Elecsys® Anti-SARS-CoV-2 S ECLIA assay (Roche Diagnostics AG, Rotkreuz, Switzerland), a quantitative electrochemiluminescence immunometric method. Results: At first sample, anti-SARS-CoV-2 S antibodies were detected in all serum samples (103.9 ± 54.9 U/mL) and only in two (40%) milk samples with a low concentration (1.2 ± 0.3 U/mL). At the second sample, collected 7 days after the second dose, anti-SARS-CoV-2 S antibodies were detected in all serum samples (3875.7 ± 3504.6 UI/mL) and in all milk samples (41.5 ± 47.5 UI/mL). No correlation was found between the level of serum and milk antibodies; the milk antibodies/serum antibodies ratio was on average 2% (range: 0.2–8.4%). Conclusion: We demonstrated a release of anti-SARS-CoV-2 S antibodies in the breast milk of women vaccinated with mRNABNT162b2. Vaccinating breastfeeding women could be a strategy to protect their infants from COVID-19 infection.

Presence and Levels of Galactosyllactoses and Other Oligosaccharides in Human Milk and Their Variation during Lactation and According to Maternal Phenotype.

Among the human milk oligosaccharides (HMOS), the galactosyllactoses (GLs) are only limitedly studied. This study aims to describe the presence and relative levels of HMOS, including GLs, in human milk (HM) according to maternal Secretor and Lewis (SeLe) phenotype and lactation stage. Relative levels of 19 HMOS were measured in 715 HM samples collected in the first 4 months postpartum from 371 donors participating in the PreventCD study. From a subset of 24 Dutch women (171 HM samples), samples were collected monthly up to 12 months postpartum and were additionally analyzed for relative and absolute levels of β6′-GL, β3′-GL and α3′-GL. Maternal SeLe phenotype or HM group was assigned based on the presence of specific fucosylated HMOS. Most HMOS, including β6′- and β3′-GL, were present in the vast majority (≥75%) of HM samples, whereas others (e.g., LNDFH II, 2′-F-LNH and α3′-GL) only occurred in a low number (<25%) of samples. Clear differences were observed between the presence and relative levels of the HMOS according to the maternal phenotype and lactation stage. Absolute concentrations of β6′-GL and β3′-GL were higher in HM group IV samples compared to samples of the other three HM groups. β3′-GL was also higher in HM group II samples compared to HM group I samples. β3′-GL and β6′-GL were stable over lactation stages. In conclusion, presence and levels of HMOS vary according to HM group and lactation stage. Not all HMOS behave similarly: some HMOS depend strongly on maternal phenotype and/or lactation stage, whereas others do not. β3′-GL and β6′-GL were present in low concentrations in over 75% of the analyzed HM samples and showed differences between HM groups, but not between the lactation stages.

Quality study of Holder pasteurization of donor human milk in a neonatal personalized nutrition unit

ObjectiveHolder pasteurization is the technique used most frequently in milk banks to minimize the risk of transmission of infectious agents. Different pasteurization devices have been described that generally use hot water or air as heat sources. In our study, we analysed the quality of pasteurization achieved with a new automated water-free pasteurizer in a neonatal personalized nutrition unit in which donated milk from mothers of infants delivered at different gestational ages and of different postnatal ages is pasteurized. Material and methodsWe analysed the temperatures of different phases of pasteurization with 8 external probes distributed evenly throughout the pasteurizer. We applied the optimal range criteria established by the European Milk Bank Association (EMBA) to assess the quality of pasteurization. We also analysed the macronutrient composition of 8 samples of donor human milk of different volumes before and after automated pasteurization. ResultsWe did not find significant differences in the following parameters under study: time from 58 °C to 62.5 °C, duration of plateau, highest temperature during plateau and length of exposure to temperatures over 58 °C. The macronutrient analysis showed significant changes in fat content but not in protein or lactose content. ConclusionsHolder pasteurization of human milk with a water-free pasteurizer met the quality standards recommended by the European Milk Bank Association independently of the quantity of milk pasteurized in each bottle and with significant changes in the fat content but not in the protein or lactose content.

The Levels of SARS-CoV-2 Specific Antibodies in Human Milk Following Vaccination.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines are being administered around the world; however, lactating women were excluded from SARS-CoV-2 vaccine trials. Therefore, knowledge about the effect of vaccination in this specific group is limited. This information is essential to empower lactating women to make a well-informed decision on their choice for vaccination. After natural infection, SARS-CoV-2 specific antibodies are present in human milk, which might offer protection for her newborn. The dynamics of these antibodies in human milk following vaccination remain to be elucidated. To determine the effect of vaccination with BNT162b2 on the levels of SARS-CoV-2 specific IgA in human milk. In this prospective longitudinal study, we included lactating women who received the BNT162b2 vaccine. Human milk samples were collected prior to vaccination and 3, 5, 7, 9, 11, 13, and 15 days after both vaccine doses. Samples were analyzed using enzyme-linked immunosorbent assay against the spike protein of SARS-CoV-2. In total, 366 human milk samples from 26 lactating women were analyzed. A biphasic response was observed, with SARS-CoV-2 specific immunoglobulin A (IgA) starting to increase between day 5 and 7 after the first dose of the vaccine. After the second dose, an accelerated IgA antibody response was observed. After vaccination with the mRNA-based BNT162b2 vaccine, a SARS-CoV-2 specific antibody response was observed in human milk. The presence of SARS-CoV-2 specific IgA after vaccination is important as antibodies are transferred via human milk, and thereby might provide protection to infants against COVID-19.

Novel Class of Human Milk Oligosaccharides Based on 6'-Galactosyllactose Containing N-Acetylglucosamine Branches Extended by Oligogalactoses.

Human milk oligosaccharides (HMOs) have attracted much attention in recent years not only as a prebiotic factor but also in particular as an essential component of infant nutrition in relation to their impact on innate immunity. The backbone structures of complex HMOs generally contain single or repetitive lacto-N-biose (type 1) or lactosamine (type 2) units in either linear or branched chains extending from a lactose core. While all known branched structures originate from the 3,6-substitution of the lactosyl core galactose, we here describe a new class of HMOs that tentatively branch at the terminal galactose of 6'-galactosyllactose. Another novel feature of this class of HMOs was found in linear oligo-galactosyl chains linked to one of the N-acetylglucosamine (GlcNAc) branches. The novel structures exhibit general formulas with hexose versus hexosamine contents of 5/2 to 8/2 and can be designated as high-galactose (HG)-HMOs. In addition, up to three fucosyl residues are linked to the octa- to dodecasaccharides, which were detected in two human milk samples from the Lewis blood-group-defined donors. Structural analyses of methylated glycans and their alditols comprised matrix-assisted laser desorption ionization mass spectrometry, electrospray-(collision-induced dissociation) mass spectrometry and linkage analyses by gas chromatography-mass spectrometry of the derived partially methylated alditol acetates. Enzymatic degradation by the application of β1-3,4-specific galactosidase supported the presence of terminal galactose-linked β1-6 to one of the two GlcNAc branches. The mass spectrometry glycomic data have been deposited at the GlycoPOST archive with the data set identifier GPST000191 (Username: franz.hanisch@uni-koeln.de; Password: Soma1Dita2Carb. Watanabe, Y. GlycoPOST realizes FAIR principles for glycomics mass spectrometry data. Nucleic Acids Res.2021,49, D1523-D1528).

Maternal dietary patterns are associated with human milk composition in Chinese lactating women

ObjectivesDietary patterns are a useful tool to study the impact of overall maternal diet on human milk (HM) composition beyond single foods or nutrients. The present study aimed to identify dietary patterns among Chinese lactating women and assess their associations with HM macronutrient composition. MethodsDietary intake data and HM samples were collected from 122 Chinese mothers at three to five study visits during the first 52 d postpartum. Dietary patterns were derived using principal component analysis. Cross-sectional associations of dietary patterns and HM macronutrients were assessed using multivariable linear regression models adjusted for total energy intake. All analyses were done separately for colostrum (postpartum days 0-7) and mature milk (postpartum days 8-52). ResultsFour dietary patterns were identified: high-in-animal-foods, high-in-eggs, high-in-plant-foods, and high-in-fruits. Compared with the lowest tertile (T1), participants in the highest tertile (T3) of the high-in-animal-foods and high-in-plant-foods patterns had lower protein (respectively, T3 − T1 = −1.09 g/100 mL, Ptrend = 0.002; T3 − T1 = −0.54 g/100 mL, Ptrend = 0.001) and higher fat (respectively, T3 − T1 = 0.86 g/100 mL, Ptrend = 0.040; T3 − T1 = 0.40 g/100 mL, Ptrend = 0.004) concentrations in colostrum. In contrast, in mature milk the high-in-animal-foods pattern was positively associated with carbohydrates (T3 − T1 = 0.53 g/100 mL, Ptrend = 0.008) and the high-in-plant-foods pattern was negatively associated with fat (T3 − T1 = −0.64 g/100 mL, Ptrend = 0.002). The high-in-eggs pattern was weakly positively associated with protein concentration in mature milk (T3 − T1 = 0.10 g/100 mL, Ptrend = 0.023). ConclusionsMaternal dietary patterns with high proportions of animal and plant-based foods were associated with higher fat and lower protein concentrations in colostrum. Different associations were found in mature milk. Dietary-pattern analysis provides an opportunity to characterize total diet and may be more predictive of HM composition than single foods or nutrients.

Macronutrient analysis of human milk and factors associated with its composition in mothers of preterm infants ≤ 32 weeks.

We conducted an exploratory longitudinal study to evaluate the macronutrient composition of human milk in mothers delivering very preterm infants ≤ 32 weeks over the first 4 weeks of lactation and the association of human milk composition with maternal and neonatal factors A total of 213 human milk samples collected in the morning between 8 am and 12 pm from 60 eligible mothers were analyzed on 7 (n = 60), 14 (n = 60), 21 (n = 52), and 28 (n = 41) days of lactation by infrared transmission spectroscopy. The true protein content decreased significantly over 4 weeks (mean difference (95% confidence interval)) (MD (95% CI)) week 1 and week 4 = 0.2 g (0.037 to 0.363, P = 0.009)). On the contrary, the mean fat and calorie content showed significant increase over time (MD (95% CI)) = - 1.03 g (- 1.719 to - 0.343, P = 0.001) and - 9.0 kcal/dl (- 15.170 to - 2.830, P = 0.001), respectively). There was no difference in the carbohydrate content of human milk over 4 weeks. Macronutrient composition was independent of maternal parity, mode of delivery, pre-pregnancy body mass index, umbilical artery Doppler flows, previous breast feeding experience, neonatal centile status, gestation, and infant's weight at birth. Multiple regression analysis of human milk composition with mother's dietary components showed no significant association. CONCLUSION : We conclude that in mothers who deliver very preterm infants ≤ 32 weeks, true protein content decreased, fat and calorie content increased, and carbohydrate content remained stable in human milk during first 4 weeks of lactation. Human milk macronutrient composition was independent of various maternal and neonatal factors including maternal body mass index and dietary intake. TRIAL REGISTRATION : CTRI/2017/02/007895 What is Known: • Preterm human milk has high temporal and inter-individual variation in the macronutrient composition. What is New: • In mothers who deliver very preterm infants < 32 weeks, true protein content decreases, fat and calorie content increases, and carbohydrate content remains stable in human milk during first 4 weeks of lactation. • Human milk macronutrient composition is independent of various maternal and neonatal factors including maternal body mass index and dietary intake.

Human Milk Oligosaccharide Profiles over 12 Months of Lactation: The Ulm SPATZ Health Study.

Human milk oligosaccharides (HMOs) have specific dose-dependent effects on child health outcomes. The HMO profile differs across mothers and is largely dependent on gene expression of specific transferase enzymes in the lactocytes. This study investigated the trajectories of absolute HMO concentrations at three time points during lactation, using a more accurate, robust, and extensively validated method for HMO quantification. We analyzed human milk sampled at 6 weeks (n = 682), 6 months (n = 448), and 12 months (n = 73) of lactation in a birth cohort study conducted in south Germany, using label-free targeted liquid chromatography mass spectrometry (LC-MS2). We assessed trajectories of HMO concentrations over time and used linear mixed models to explore the effect of secretor status and milk group on these trajectories. Generalized linear model-based analysis was used to examine associations between HMOs measured at 6 weeks of lactation and maternal characteristics. Results: Overall, 74%, 18%, 7%, and 1% of human milk samples were attributed to milk groups I, II, III, and IV, respectively. Most HMO concentrations declined over lactation, but some increased. Cross-sectionally, HMOs presented high variations within milk groups and secretor groups. The trajectories of HMO concentrations during lactation were largely attributed to the milk group and secretor status. None of the other maternal characteristics were associated with the HMO concentrations. The observed changes in the HMO concentrations at different time points during lactation and variations of HMOs between milk groups warrant further investigation of their potential impact on child health outcomes. These results will aid in the evaluation and determination of adequate nutrient intakes, as well as further (or future) investigation of the dose-dependent impact of these biological components on infant and child health outcomes.

Changes in Antisecretory Factor in Human Milk During the Postpartum and Length of Gestation.

BackgroundPreterm infants are more susceptible to inflammatory complications than term infants. Human milk contains numerous bioactive components protecting the newborn infant. Antisecretory factor, a protein regulating secretory and inflammatory processes by complex binding with complement factors, is present in human milk.Research AimsTo describe antisecretory factor (1) in mother’s own milk in term and preterm infants; and (2) in donor milk before and after Holder pasteurization.MethodsThe study was prospective, longitudinal, explorative, and descriptive. Antisecretory factor-compleasome was determined using sandwich enzyme-linked immunosorbent assay in longitudinal human milk samples over 12 weeks from mothers (N = 87) of term (n = 41) and of preterm (n = 46) infants and 20 anonymized donor human milk samples before and after Holder pasteurization.ResultsAntisecretory factor-compleasome was overall higher in colostrum versus mature milk (p < .001) and no difference was found in term or preterm colostrum (p = .82). In mature milk, compleasome was higher and more variable in the preterm group (p = .01). After Holder pasteurization, compleasome levels increased (p < .001).ConclusionAntisecretory factor followed the pattern of other immunological factors with high levels in colostrum. After preterm birth, levels of antisecretory factor were higher and more variable in mature milk. Holder pasteurization did not degrade antisecretory factor, indicating preserved anti-inflammatory properties in donor human milk.

Combining HPAEC-PAD, PGC-LC-MS, and 1D 1H NMR to Investigate Metabolic Fates of Human Milk Oligosaccharides in 1-Month-Old Infants: a Pilot Study.

A solid-phase extraction procedure was optimized to extract 3-fucosyllactose and other human milk oligosaccharides (HMOs) from human milk samples separately, followed by absolute quantitation using high-performance anion-exchange chromatography-pulsed amperometric detection and porous graphitized carbon-liquid chromatography–mass spectrometry, respectively. The approach developed was applied on a pilot sample set of 20 human milk samples and paired infant feces collected at around 1 month postpartum. One-dimensional 1H nuclear magnetic resonance spectroscopy was employed on the same samples to determine the relative levels of fucosylated epitopes and sialylated (Neu5Ac) structural elements. Based on different HMO consumption patterns in the gastrointestinal tract, the infants were assigned to three clusters as follows: complete consumption; specific consumption of non-fucosylated HMOs; and, considerable levels of HMOs still present with consumption showing no specific preference. The consumption of HMOs by infant microbiota also showed structure specificity, with HMO core structures and Neu5Ac(α2-3)-decorated HMOs being most prone to degradation. The degree and position of fucosylation impacted HMO metabolization differently.