Human Milk Microbiota and Oligosaccharides: A Glimpse into Benefits, Diversity, and Correlations

Human milk oligosaccharide secretion dynamics during breastfeeding and its antimicrobial role: A systematic review

BACKGROUND

Human milk oligosaccharides (HMOs) are bioactive components of breast milk with diverse health benefits, including shaping the gut microbiota, modulating the immune system, and protecting against infections. HMOs exhibit dynamic secretion patterns during lactation, influenced by maternal genetics and environmental factors. Their direct and indirect antimicrobial properties have garnered significant research interest. However, a comprehensive understanding of the secretion dynamics of HMOs and their correlation with antimicrobial efficacy remains underexplored.

AIM

To synthesize current evidence on the secretion dynamics of HMOs during lactation and evaluate their antimicrobial roles against bacterial, viral, and protozoal pathogens.

METHODS

A systematic search of PubMed, Scopus, Web of Science, and Cochrane Library focused on studies investigating natural and synthetic HMOs, their secretion dynamics, and antimicrobial properties. Studies involving human, animal, and in vitro models were included. Data on HMO composition, temporal secretion patterns, and mechanisms of antimicrobial action were extracted. Quality assessment was performed using validated tools appropriate for study design.

RESULTS

A total of 44 studies were included, encompassing human, animal, and in vitro research. HMOs exhibited dynamic secretion patterns, with 2′-fucosyllactose (2′-FL) and lacto-N-tetraose peaking in early lactation and declining over time, while 3-fucosyllactose (3-FL) increased during later stages. HMOs demonstrated significant antimicrobial properties through pathogen adhesion inhibition, biofilm disruption, and enzymatic activity impairment. Synthetic HMOs, including bioengineered 2′-FL and 3-FL, were structurally and functionally comparable to natural HMOs, effectively inhibiting pathogens such as Pseudomonas aeruginosa , Escherichia coli , and Campylobacter jejuni . Additionally, HMOs exhibited synergistic effects with antibiotics, enhancing their efficacy against resistant pathogens.

CONCLUSION

HMOs are vital in antimicrobial defense, supporting infant health by targeting various pathogens. Both natural and synthetic HMOs hold significant potential for therapeutic applications, particularly in infant nutrition and as adjuncts to antibiotics. Further research, including clinical trials, is essential to address gaps in knowledge, validate findings, and explore the broader applicability of HMOs in improving maternal and neonatal health.

Comprehensive review on human Milk oligosaccharides: Biosynthesis, structure, intestinal health benefits, immune regulation, neuromodulation mechanisms, and applications

This review provides a comprehensive analysis of the biosynthetic pathways of various oligosaccharides in Escherichia coli, structural characteristics, and bioactive mechanisms of human milk oligosaccharides (HMOs), with a particular emphasis on their roles in gut health, immune modulation, and neurodevelopment. HMOs primarily function as prebiotics, facilitating the growth of beneficial bacteria such as Bifidobacterium to maintain microbial homeostasis, with a discussion on the synergistic role of carbohydrate-binding modules (CBMs). In immune modulation, HMOs interact with lectins on immune and epithelial cells, influencing immune responses via pathways such as Toll-like receptors (TLRs). Additionally, HMOs have been linked to enhanced cognitive, motor, and language development in infants, influencing genes such as GABRB2, SLC1A7, GLRA4, and CHRM3. The review also examines commercially available HMO-containing products and highlights future research directions and potential applications in nutrition and healthcare.

Exosomes in Breast Milk: Their Impact on the Intestinal Microbiota of the Newborn and Therapeutic Perspectives for High-Risk Neonates

Breast milk exosomes are essential for the nutrition and immune development of the newborn. These 30-150 nm extracellular vesicles contain microRNAs (miRNAs), mesessenger RNAS (mRNA)s, proteins and lipids that facilitate cellular communication and modulate the neonatal immune system. In this article, we analyse the impact of breast milk exosomes on the intestinal microbiota of the newborn, especially in high-risk neonates such as preterm infants or neonates at risk of necrotising enterocolitis (NEC). Exosomes promote the colonisation of beneficial bacteria such as Bifidobacterium and Lactobacillus and strengthen the intestinal barrier. They also regulate the immune response, balancing defence against pathogens and tolerance to non-pathogenic antigens. This effect is key for high-risk infants, who benefit from their anti-inflammatory and preventive properties against complications such as NEC. Research points to their potential therapeutic uses in neonatal care, opening up new opportunities to improve the health of vulnerable newborns through the protective effects of breast milk exosomes.

Effects of 3'-sialyllactose, saliva, and colostrum on Candida albicans biofilms

BACKGROUND

Faria et al. evaluated the initial adhesion and biofilm formation of Candida albicans in vitro in the presence of saliva, human colostrum, and 3'-sialyllactose. Colostrum applied either before or after inoculation with saliva did not differ from that of the control biofilms (p<0.05). In contrast, colostrum applied during C. albicans inoculation resulted in a higher biomass than the control (p<0.05). Saliva without colostrum decreased the biofilm biomass (p<0.05), and the application of 3'- sialyllactose reduced biofilm formation regardless of the timing of application (p<0.05). Candidiasis can present as localized or systemic infections. Disseminated infections in newborns and adults can be life-threatening, with high mortality and morbidity rates (40-60%), and rank as the fourth most common type of nosocomial infection. Oral candidiasis is a local condition affecting 10-15% of children in their first months of life. Saliva and 3'-sialyllactose can disrupt the initial development of Candida albicans biofilm. The effect of colostrum needs to be elucidated because it may hinder initial adhesion but promote fungal proliferation after application.

OBJECTIVE

The aim of this study was to investigate the effects of saliva, human colostrum, and 3'-sialyllactose on the initial adhesion and biofilm formation of Candida albicans in vitro.

METHODS

Colostrum and saliva samples were collected from 30 postpartum mothers and newborns, respectively. An 18h culture of C. albicans was treated with colostrum, 3'-sialyllactose, saliva, or a combination of colostrum and saliva at three different time points: before, during, and 24h after C. albicans inoculation. Biofilm assays were conducted in sterile 96-well flat-bottom microtiter plates for 24h. Biofilms were fixed, washed, stained with crystal violet, and extracted. Absorbance was measured to evaluate biofilm biomass.

RESULTS

The combined application of colostrum and saliva before and after microbial inoculation did not differ from the control biofilms (p<0.05). In contrast, the combined application of colostrum and saliva during C. albicans application resulted in a higher biomass than the control (p<0.05). Saliva alone decreased the biofilm biomass (p<0.05), and the application of 3'-sialyllactose reduced biofilm formation regardless of the timing of application (p<0.05).

CONCLUSION

Saliva contributed to the proliferation of biofilms, while colostrum did not prevent initial adhesion but influenced biofilm accumulation and development. In contrast, 3'-sialyllactose significantly decreased biofilm formation at all application times. These findings underscore the importance of colostrum as a potent oral antimicrobial biofluid.

Comparative analysis of proteomics and transcriptomics reveals novel mechanism underlying the antibacterial activity and immune-enhancing properties of horse milk

Background

Horse milk is a highly valuable organic food that is a promising alternative to cow milk, exhibiting plenty of healthy and immune benefits to human. However, identification of proteins associated human wellness and underlying molecular mechanism in horse milk remain unclear.

Methodology

Label-free mass spectrometry-based protein quantification technology was employed to investigate protein composition of animal milk, including cow, goat, camel and horse milk. Prokaryotic expression and disk diffusion assay were applied to acquire and evaluate in vitro antimicrobial activity of candidate proteins. RAW264.7 macrophage model cell line was used to validate effect of proteins on cytotoxicity, apoptosis and immune induction. ROS probe detected cell ROS change and RT-qPCR verified expression of immune response genes induced by proteins. Microscopy was used to observe the effects of protein on the morphological characteristics of bacteria, further transcriptome analysis was performed to investigate transcriptional changes of bacteria induced by candidate proteins.

Results

A total of 1,335 proteins was identified in cow, goat, camel and horse milk. GO enrichment analysis showed that the proteins related to protein degradation were highly expressed in horse milk compared to other three types of milk, contributing to easier assimilation and palatability. KEGG analysis showed that horse milk contained abundant antimicrobial associated proteins relevant to pathogenic bacterial resistance, leading to the decreased risk of pathogenic diseases. A higher accumulation of proteins associated with caffeine metabolism, amino acid biosynthesis, and glycolysis/gluconeogenesis in horse milk contributes to its distinctive flavor. Notably, highly expressed proteins in horse milk were closely linked to immune signaling pathways, functioning as immune modulators. Importantly, we identified four highly expressed antimicrobial associated proteins in horse milk including LPO, B2M, CD14 and PGL, among them, PGL functioned dually by in vitro antibacterial activity and immune activation. Further transcriptome analysis demonstrated that PGL exerted significant transcriptional changes to bacteria. Enrichment analysis showed PGL could inhibit growth of P. aeruginosa and E. coli by repressing the biosynthesis of secondary metabolites.

Conclusion

Comparative proteomics revealed immune enhancement and nutrient composition of horse milk compared to cow, goat and camel milk. Identification of PGL showed antibacterial activity and potential medicinal value.

Engineering glycolytic pathway for improved Lacto-N-neotetraose production in pichia pastoris

Lacto-N-neotetraose (LNnT) is a primary solid component of human milk oligosaccharides (HMOs) with various promising health effects for infants. LNnT production by GRAS (generally recognized as safe) microorganisms has attracted considerable attention. However, few studies have emphasized Pichia Pastoris as a cell factory for LNnT's production. Here, we have reported the first-ever synthesis of LNnT employing P. pastoris as the host. Initially, LNnT biosynthetic pathway genes β-1,3-N-acetylglucosaminyltransferase (lgtA) and β-1,4-galactostltransferase (lgtB) along with lactose permease (lac12) and galactose epimerase (gal10) were integrated into the genome of P. pastoris, but only 0.139 g/L LNnT was obtained. Second, the titer of LNnT was improved to 0.162 g/L via up-regulating genes to strengthen the supply of precursors, UDP-GlcNAc (Uridine diphosphate N-acetylglucosamine) and UDP-Gal (Uridine diphosphate galactose), for LNnT biosynthesis. Third, by knocking out critical mediator pfk (6-phosphofructokinase) genes in glycolysis, the major glucose metabolic flux was rewired to the LNnT biosynthesis pathway. As a result, the strain accumulated 0.867 g/L LNnT in YPG medium supplemented with glucose and lactose. Finally, LNnT production was increased to 1.24 g/L in a 3 L bioreactor. The work aimed to explore the potential of P. pastoris as a for LNnT production.

Integrating the milk microbiome signatures in mastitis: milk-omics and functional implications

Mammalian milk contains a variety of complex bioactive and nutritional components and microorganisms. These microorganisms have diverse compositions and functional roles that impact host health and disease pathophysiology, especially mastitis. The advent and use of high throughput omics technologies, including metagenomics, metatranscriptomics, metaproteomics, metametabolomics, as well as culturomics in milk microbiome studies suggest strong relationships between host phenotype and milk microbiome signatures in mastitis. While single omics studies have undoubtedly contributed to our current understanding of milk microbiome and mastitis, they often provide limited information, targeting only a single biological viewpoint which is insufficient to provide system-wide information necessary for elucidating the biological footprints and molecular mechanisms driving mastitis and milk microbiome dysbiosis. Therefore, integrating a multi-omics approach in milk microbiome research could generate new knowledge, improve the current understanding of the functional and structural signatures of the milk ecosystem, and provide insights for sustainable mastitis control and microbiome management.

Comparative study of the oligosaccharide profile in goat, bovine, sheep, and human milk whey

Milk oligosaccharides are high added value compounds that could be obtained by exploiting cheese whey, a byproduct of dairy industry. The objective was to compare the abundance and diversity of oligosaccharides in whey samples from domestic animals and humans. During fresh cheese making, whey samples were collected and analyzed by untargeted and targeted small molecule analysis using high-resolution mass-spectrometry. A great similarity in the metabolite profile between goat and sheep was observed. Up to 11 oligosaccharides were observed in the sheep whey from those typically found in humans. The concentration of 2'-Fucosyllactose (0.136 ± 0.055 g/L) and 3-Fucosyllactose (0.079 ± 0.009 g/L) were significantly higher (p-value <0.01) in sheep whey, while the concentration of 3'-Sialyllactose (0.826 ± 0.638 g/L) was higher in goat whey. No significant differences were observed between goat and sheep whey for the other oligosaccharides (p-value >0.05). Therefore, sheep and goat whey could become an important source of oligosaccharides through their revalorization.

Free oligosaccharides in serum

Glycans are sugars/sugar chains that are usually linked to proteins or lipids. The attachment of glycans often results in alterations of physicochemical/physiological properties of the carrier molecules, e.g., glycosylation of proteins can modulate their fate, intracellular localization, or interaction with cells/other proteins. On the other hand, unconjugated N-glycans (free N-glycans; FNGs) have been identified in the cytosol of eukaryotic cells. The processing pathway of intracellular FNGs has been clarified in recent years, but their biological functions remain unclear. Free oligosaccharides have also been identified in the sera of various animals. Structurally, these extracellular free glycans can be classified into three types: sialyl FNGs, oligomannose-type FNGs, and sialyl lactose/N-acetyllactosamine-type glycans. The extracellular FNGs show different structural features from intracellular FNGs, implying that their mechanism of formation is distinct. This mini-review summarizes current knowledge about the structures and formation mechanisms of free oligosaccharides in serum, and suggests their possible biological functions.

Human Milk Archaea Associated with Neonatal Gut Colonization and Its Co-Occurrence with Bacteria

Archaea have been identified as early colonizers of the human intestine, appearing from the first days of life. It is hypothesized that the origin of many of these archaea is through vertical transmission during breastfeeding. In this study, we aimed to characterize the archaeal composition in samples of mother-neonate pairs to observe the potential vertical transmission. We performed a cross-sectional study characterizing the archaeal diversity of 40 human colostrum-neonatal stool samples by next-generation sequencing of V5-V6 16S rDNA libraries. Intra- and inter-sample analyses were carried out to describe the Archaeal diversity in each sample type. Human colostrum and neonatal stools presented similar core microbiota, mainly composed of the methanogens Methanoculleus and Methanosarcina. Beta diversity and metabolic prediction results suggest homogeneity between sample types. Further, the co-occurrence network analysis showed associations between Archaea and Bacteria, which might be relevant for these organisms' presence in the human milk and neonatal stool ecosystems. According to relative abundance proportions, beta diversity, and co-occurrence analyses, the similarities found imply that there is vertical transmission of archaea through breastfeeding. Nonetheless, differential abundances between the sample types suggest other relevant sources for colonizing archaea to the neonatal gut.

Associations of Maternal Salivary Cortisol and Psychological Symptoms With Human Milk's Microbiome Composition

OBJECTIVE

Human milk (HM) is considered the best source of infant nutrition with many benefits for the infant. However, pregnancy changes can lead to increased stress in some women, which might affect HM composition. Although studies have demonstrated a link between maternal psychopathology and child development, it remains unclear how maternal psychobiological changes can be intergenerationally transmitted. We aimed to investigate the associations of maternal stress, depressive symptoms, and anxiety symptoms with the HM microbiome; to analyze these parameters in relation to HM glucocorticoid concentrations; and to explore the influence of HM glucocorticoids on HM bacterial composition.

METHODS

One hundred women completed psychological questionnaires (e.g., EPDS, STAI, GAS) at 34-36 weeks' gestation and in the early postpartum period and provided saliva at 34-36 and 38 weeks' gestation. HM samples were collected in the early postpartum. Microbiota were analyzed using 16S rRNA amplicon sequencing.

RESULTS

Birth anxiety was negatively correlated with Alphaproteobacteria (τ = -0.20, FDR = 0.01), whereas in the postpartum period, anxiety symptoms were negatively correlated with different taxa. The sum of postpartum-related symptoms was linked to lower Propionibacteriales. Salivary cortisol AUCg at 34-36 weeks was negatively correlated with Stenotrophomonas (τ = -0.24, FDR = 0.05), whereas HM cortisol was positively correlated with Streptococcus mitis (τ = 0.26, FDR = 0.03) and Gemella haemolysans (τ = 0.24, FDR = 0.02). No associations emerged between psychobiological parameters and HM glucocorticoids.

CONCLUSIONS

Higher perinatal psychological symptoms and prenatal salivary cortisol AUCg were associated with lower relative abundances of different bacteria, whereas higher HM cortisol was linked to higher Gemella and Streptococcus. These findings suggest a negative association between high maternal psychobiological symptoms and relative abundances of the milk microbiota.

2'-Fucosyllactose and 3'-Sialyllactose Reduce Mortality in Neonatal Enteroaggregative Escherichia coli Infection by Improving the Construction of Intestinal Mucosal Immunity

Human milk oligosaccharides could prevent pathogenic bacterial infections in neonates; however, direct in vivo anti-infection evidence was still lacking. Here, we systematically evaluated the effects of 2'-fucosyllactose (2'-FL) and 3'-sialyllactose (3'-SL) on the structural development and functional maturation in neonates and their defense against enteroaggregative Escherichia coli infection. It was found that supplementation with 2'-FL and 3'-SL improved the resistance of weaned mice to enteroaggregative E. coli. The mechanism related to the promotion of 2'-FL and 3'-SL in the maturation of intestinal mucosal immunity by promoting stem cell differentiation, mucus layer integrity, and tight junction formation. 2'-FL and 3'-SL significantly increased the ratio of Th1 and Treg cells in the lamina propria, contents of short-chain fatty acids, as well as the serum content of IgA. This study lays a theoretical basis for the application of 2'-FL and 3'-SL in infant formula, as well as the development of intestinal health products.

The Impact of Complementary Feeding on Fecal Microbiota in Exclusively Breast-Fed Infants with Cystic Fibrosis (A Descriptive Study)

BACKGROUND/OBJECTIVES

Early life gut microbiota plays a pivotal role in shaping immunity, metabolism, and overall health outcomes. This is relevant in healthy infants but may be even more crucial in infants with chronic devastating diseases, such as cystic fibrosis (CF). While the introduction of solid foods in healthy infants modifies the composition of colonic microbiota, less knowledge is available on those with CF. The aim of this descriptive observational study was to assess the composition of fecal microbiota in six exclusively breast-fed infants with CF, and then explore the changes induced upon the introduction of different foods.

METHODS

two types of fecal samples were collected from each subject: one during the exclusive-breastfeeding period, and the other after incorporating each new food in the ad libitum diet. The microbiota composition was analyzed by 16S rRNA amplicon sequencing.

RESULTS

Wide heterogenicity in the composition at the phylum level (variable proportions of Actinobacteriota, Proteobacteria, and Firmicutes, and the absence of Bacteroidota in all subjects) was found, and different enterotypes were characterized in each subject by the main presence of one genus: Bifidobacterium in Subject 1 (relative abundance of 54.4%), Klebsiella in Subject 3 (49.1%), Veillonella in Subjects 4 and 5 (32.7% and 36.9%, respectively), and Clostridium in Subject 6 (48.9%). The transition to complementary feeding induced variable changes in microbiota composition, suggesting a subject-specific response and highlighting the importance of inter-individual variation.

CONCLUSIONS

Further studies are required to identify which foods contribute to shaping colonic microbiota in the most favorable way for patients with CF using a personalized approach.

Influence of Nutrition on Growth and Development of Metabolic Syndrome in Children

Obesity is currently an increasing public health burden due to its related metabolic and cardiovascular complications. In Western countries, a significant number of people are overweight or obese, and this trend is, unfortunately, becoming increasingly common even among the pediatric population. In this narrative review, we analyzed the role of nutrition during growth and its impact on the risk of developing metabolic syndrome and cardiovascular complications later in life. An impactful role in determining the phenotypic characteristics of the offspring is the parental diet carried out before conception. During intrauterine growth, the main risk factors are represented by an unbalanced maternal diet, excessive gestational weight gain, and impaired glycemic status. Breastfeeding, on the other hand, has many beneficial effects, but at the same time the quality of breast milk may be modified if maternal overweight or obesity subsists. Complementary feeding is likewise pivotal because an early introduction before 4 months of age and a high protein intake contribute to weight gain later. Knowledge of these mechanisms may allow early modification of risk factors by implementing targeted preventive strategies.

Multi-omics analysis of five species of milk and specific composition links within each species

The gold standard of milk is human milk, not cow milk. The present study expects to explored the comprehensive nutritional value of different kinds of milk and the differences between them through multi-omics analysis and found functional components that are more similar to human milk. This study employed untargeted LC-MS/MS metabolomics, untargeted LC-MS/MS lipidomics, and 4D label-free proteomics analysis techniques. The findings revealed substantial disparities in metabolites, lipids, and proteins among the five types of milk. Notably, pig milk exhibited a remarkable abundance of N-acetylneuraminic acid (Neu5Ac) and specific polar lipids. Yak milk stood out with significantly elevated levels of creatine and lipoprotein lipase (LPL) compared to other species. Buffalo milk boasted the highest concentrations of L-isoleucine, echinocystic acid, and alkaline phosphatase, tissue-nonspecific isozyme (ALPL). The concentrations of iminostilbene and osteopontin (OPN) were higher in cow milk.

The Association Between Maternal Psychological Health and Human Milk Oligosaccharide Composition

Background and Objective: Human milk oligosaccharides (HMOs) are carbohydrates abundant in human breast milk. Their composition varies widely among women, and prior research has identified numerous factors contributing to this variation. However, the relationship between maternal psychological health and HMO levels is currently unknown. Thus, our objective was to identify whether maternal stress, anxiety, or depressive symptoms are associated with HMOs. Methods: Data originated from 926 lactating individuals from the UC San Diego Human Milk Biorepository. Nineteen prevalent HMOs were assayed using high-performance liquid chromatography. Participants self-reported measures of the Edinburgh Postnatal Depression Scale (n = 495), State-Trait Anxiety Inventory S-Scale (n = 486), and/or Perceived Stress Scale (n = 493) within 60 days of their milk collection; their results were categorized using standard screening cutoffs. HMOs were assessed individually and grouped by principal component analysis (PCA), and associations with maternal psychological symptoms were analyzed using multivariable linear regression adjusted for covariates. Results: After Bonferroni correction (p < 0.002), the following HMOs significantly varied with maternal psychological distress in multivariate analysis: lacto-N-fucopentaose III (LNFP III) and lacto-N-hexaose (LNH) among Secretors with depressive symptoms and difucosyllactose (DFLac), LNFP III, and disialyl-LNH (DSLNH) among Secretors with stress. In PCA, depressive symptoms and stress were associated with one principal component among Secretors. No HMOs varied with anxiety symptoms. Conclusions: Several HMOs varied with maternal depressive symptoms and stress, suggesting a relationship between maternal psychological health and breast milk composition. Additional studies are needed to determine the impact of this variation on infant health.

Exploring the Prebiotic Potentials of Hydrolyzed Pectins: Mechanisms of Action and Gut Microbiota Modulation

The intestinal microbiota is a complex ecosystem where the microbial community (including bacteria) can metabolize available substrates via metabolic pathways specific to each species, often related in symbiotic relations. As a consequence of using available substrates and microbial growth, specific beneficial metabolites can be produced. When this reflects the health benefits for the host, these substrates can be categorized as prebiotics. Given that most prebiotic candidates must have a low molecular weight to be further metabolized by the microbiota, the role in the preliminary biological pretreatment is crucial. To provide proper substrates to the intestinal microbiota, a strategy could be to decrease the complexity of polysaccharides and reduce the levels of polymerization to low molecular weight for the target molecules, driving better solubilization and the consequent metabolic use by intestinal bacteria. When high molecular weight pectin is degraded (partially depolymerized), its solubility increases, thereby improving its utilization by gut microbiota. With regards to application, prebiotics have well-documented advantages when applied as food additives, as they improve gut health and can enhance drug effects, all shown by in vitro, in vivo, and clinical trials. In this review, we aim to provide systematic evidence for the mechanisms of action and the modulation of gut microbiota by the pectin-derived oligosaccharides produced by decreasing overall molecular weight after physical and/or chemical treatments and to compare with other types of prebiotics.

The Influence of Maternal Lifestyle Factors on Human Breast Milk Microbial Composition: A Narrative Review

Human breast milk (HBM) is considered the gold standard for infant nutrition due to its optimal nutrient profile and complex composition of cellular and non-cellular components. Breastfeeding positively influences the newborn's gut microbiota and health, reducing the risk of conditions like gastrointestinal infections and chronic diseases (e.g., allergies, asthma, diabetes, and obesity). Research has revealed that HBM contains beneficial microbes that aid gut microbiota maturation through mechanisms like antimicrobial production and pathogen exclusion. The HBM microbiota composition can be affected by several factors, including gestational age, delivery mode, medical treatments, lactation stage, as well as maternal lifestyle habits (e.g., diet, physical activity, sleep quality, smoking, alcohol consumption, stress level). Particularly, lifestyle factors can play a significant role in shaping the HBM microbiota by directly modulating the microbial composition or influencing the maternal gut microbiota and influencing the HBM microbes through the enteromammary pathway. This narrative review of current findings summarized how maternal lifestyle influences HBM microbiota. While the influence of maternal diet on HBM microbiota is well-documented, indicating that dietary patterns, especially those rich in plant-based proteins and complex carbohydrates, can positively influence HBM microbiota, the impact of other lifestyle factors is poorly investigated. Maintaining a healthy lifestyle during pregnancy and breastfeeding is crucial for the health of both mother and baby. Understanding how maternal lifestyle factors influence microbial colonization of HBM, along with their interactions and impact, is key to developing new strategies that support the beneficial maturation of the infant's gut microbiota.

Sociodemographic and Psychological Factors Influencing Human Milk Donation: A Cross-Sectional Study of 420 Lactating Mothers in Vijayapura

Background Breastfeeding is crucial for infant health, but not all mothers can breastfeed due to various constraints. Making human milk banks (HMBs) is essential for providing donor milk to preterm and sick infants. Methods  This is a cross-sectional study at Shri BM Patil Medical College Hospital and Research Centre in Vijayapura involving 420 lactating mothers. Convenience sampling and semi-standardized interviews were used to assess socio-demographics, maternal factors, and attitudes toward milk donation. Results Among the 420 lactating mothers surveyed, urban mothers were significantly more likely to have received breastfeeding counseling (56.7% vs. 41.4%) and were more aware of milk bank donations (20.0% vs. 11.4%) than rural mothers. Logistic regression analysis revealed that urban residence, higher education, and prior knowledge of milk donation were significant predictors of willingness to donate breast milk. Conclusion The findings emphasize the importance of education and awareness, particularly in rural areas, to promote milk donation. Addressing socio-economic disparities and sharing personal experiences can also encourage donations. Targeted educational programs are crucial for enhancing donation rates and improving newborn health outcomes, making milk donation a vital area for public health initiatives.

Maternal influences on offspring food allergy

The prevalence of allergies has been globally escalating. While allergies could appear at any age, they often develop in early life. However, the significant knowledge gap in the field is the mechanisms by which allergies affect certain people but not others. Investigating early factors and events in neonatal life that have a lasting impact on determining the susceptibilities of children to develop allergies is a significant area of the investigation as it promotes the understanding of neonatal immune system that mediates tolerance versus allergies. This review focuses on the research over the recent 10 years regarding the potential maternal factors that influence offspring allergies with a view to food allergy, a potentially life-threatening cause of anaphylaxis. The role of breast milk, maternal diet, maternal antibodies, and microbiota that have been suggested as key maternal factors regulating offspring allergies are discussed here. We also suggest future research area to expand our knowledge of maternal-offspring interactions on the pathogenesis of food allergy.

Human Milk Oligosaccharides in Combination with Galacto- and Long-Chain Fructo-Oligosaccharides Enhance Vaccination Efficacy in a Murine Influenza Vaccination Model

Early-life nutrition significantly impacts vaccination efficacy in infants, whose immune response to vaccines is weaker compared to adults. This study investigated vaccination efficacy in female C57Bl/6JOlaHsd mice (6 weeks old) fed diets with 0.7% galacto-oligosaccharides (GOS)/long-chain fructo-oligosaccharides (lcFOS) (9:1), 0.3% human milk oligosaccharides (HMOS), or a combination (GFH) for 14 days prior to and during vaccination. Delayed-type hypersensitivity (DTH) was measured by assessing ear swelling following an intradermal challenge. Influvac-specific IgG1 and IgG2a levels were assessed using ELISAs, while splenic T and B lymphocytes were analyzed for frequency and activation via flow cytometry. Additionally, cytokine production was evaluated using murine splenocytes co-cultured with influenza-loaded dendritic cells. Mice on the GFH diet showed a significantly enhanced DTH response (p < 0.05), increased serological IgG1 levels, and a significant rise in memory B lymphocytes (CD27+ B220+ CD19+). GFH-fed mice also exhibited more activated splenic Th1 cells (CD69+ CXCR3+ CD4+) and higher IFN-γ production after ex vivo restimulation (p < 0.05). These findings suggest that GOS/lcFOS and HMOS, particularly in combination, enhance vaccine responses by improving memory B cells, IgG production, and Th1 cell activation, supporting the potential use of these prebiotics in infant formula for better early-life immune development.

Relationship between Infant Feeding and the Microbiome: Implications for Allergies and Food Intolerances

Childhood is a critical period for immune system development, which is greatly influenced by the gut microbiome. Likewise, a number of factors affect the gut microbiome composition and diversity, including breastfeeding, formula feeding, and solid foods introduction. In this regard, several studies have previously demonstrated that breastfeeding promotes a favorable microbiome. In contrast, formula feeding and the early incorporation of certain solid foods may adversely affect microbiome development. Additionally, there is increasing evidence that disruptions in the early microbiome can lead to allergic conditions and food intolerances. Thus, developing strategies to promote optimal infant nutrition requires an understanding of the relationship between infant nutrition and long-term health. The present review aims to examine the relationship between infant feeding practices and the microbiome, as well as its implications on allergies and food intolerances in infants. Moreover, this study synthesizes existing evidence on how different eating habits influence the microbiome. It highlights their implications for the prevention of allergies and food intolerances. In conclusion, introducing allergenic solid foods before six months, alongside breastfeeding, may significantly reduce allergies and food intolerances risks, being also associated with variations in gut microbiome and related complications.

Assessment of 2'-Fucosyllactose and Lacto-N-Neotetraose Solution as an Irrigant in E. faecalis-Infected Root Canals: An In Vitro Study

BACKGROUND

Given the lack of an ideal endodontic irrigant on the market, this study evaluates the antimicrobial potential of a formulated solution of 2'-fucosyllactose and lacto-N-neotetraose against E. faecalis within infected root canals, and explores any associated impacts related to the duration of irrigation.

METHODS

32 single-rooted teeth extracted for periodontal reasons were infected with Enterococcus faecalis, and subsequently subjected to endodontic treatment with two different irrigation systems: sodium hypochlorite or a solution of 2'-fucosyllactose and lacto-N-neotetraose. These samples were then incubated in sterile culture media at 37 °C to observe microbial activity through turbidity. The culture broth of each individual sample was assessed as positive or negative by observing the turbidity or lack of turbidity in the culture at the time of evaluation.

RESULTS

the analysis of the results obtained from the comparison of groups irrigated with sodium hypochlorite or a solution of 2'-fucosyllactose and lacto-N-neotetraose demonstrates that the case solution has no bactericidal effect against E. faecalis inoculated in the endodontic system.

CONCLUSIONS

the HMOs used in this study do not have a bactericidal effect on E. faecalis inoculated in an endodontic system.

Age-specific composition of milk microbiota in Tibetan sheep and goats

This study investigates the dynamic changes in milk nutritional composition and microbial communities in Tibetan sheep and goats during the first 56 days of lactation. Milk samples were systematically collected at five time points (D0, D7, D14, D28, D56) post-delivery. In Tibetan sheep, milk fat, protein, and casein contents were highest on D0, gradually decreased, and stabilized after D14, while lactose and galactose levels showed the opposite trend. Goat milk exhibited similar initial peaks, with significant changes particularly between D0, D7, D14, and D56. 16S rRNA gene sequencing revealed increasing microbial diversity in both species over the lactation period. Principal coordinates analysis identified distinct microbial clusters corresponding to early (D0-D7), transitional (D14-D28), and mature (D56) stages. Core phyla, including Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria, dominated the milk microbiota, with significant temporal shifts. Core microbes like Lactobacillus, Leuconostoc, and Streptococcus were common in both species, with species-specific taxa observed (e.g., Pediococcus in sheep, Shewanella in goats). Furthermore, we observed a highly shared core microbiota in sheep and goat milk, including Lactobacillus, Leuconostoc, and Streptococcus. Spearman correlation analysis highlighted significant relationships between specific microbial genera and milk nutrients. For instance, Lactobacillus positively correlated with total solids, non-fat milk solids, protein, and casein, while Mannheimia negatively correlated with protein content. This study underscores the complex interplay between milk composition and microbial dynamics in Tibetan sheep and goats, informing strategies for livestock management and nutritional enhancement. KEY POINTS: • The milk can be classified into three types based on the microbiota composition • The changes of milk microbiota are closely related to the variations in nutrition • Filter out microbiota with species specificity and age specificity in the milk.

Food, nutrition, and autism: from soil to fork

Food and nutrition-related factors have the potential to impact development of autism spectrum disorder (ASD) and quality of life for people with ASD, but gaps in evidence exist. On 10 November 2022, Tufts University's Friedman School of Nutrition Science and Policy and Food and Nutrition Innovation Institute hosted a 1-d meeting to explore the evidence and evidence gaps regarding the relationships of food and nutrition with ASD. This meeting report summarizes the presentations and deliberations from the meeting. Topics addressed included prenatal and child dietary intake, the microbiome, obesity, food-related environmental exposures, mechanisms and biological processes linking these factors and ASD, food-related social factors, and data sources for future research. Presentations highlighted evidence for protective associations with prenatal folic acid supplementation and ASD development, increases in risk of ASD with maternal gestational obesity, and the potential for exposure to environmental contaminants in foods and food packaging to influence ASD development. The importance of the maternal and child microbiome in ASD development or ASD-related behaviors in the child was reviewed, as was the role of discrimination in leading to disparities in environmental exposures and psychosocial factors that may influence ASD. The role of child diet and high prevalence of food selectivity in children with ASD and its association with adverse outcomes were also discussed. Priority evidence gaps identified by participants include further clarifying ASD development, including biomarkers and key mechanisms; interactions among psychosocial, social, and biological determinants; interventions addressing diet, supplementation, and the microbiome to prevent and improve quality of life for people with ASD; and mechanisms of action of diet-related factors associated with ASD. Participants developed research proposals to address the priority evidence gaps. The workshop findings serve as a foundation for future prioritization of scientific research to address evidence gaps related to food, nutrition, and ASD.

Preparation, structural characterization, biological activity, and nutritional applications of oligosaccharides

Oligosaccharides are low-molecular-weight carbohydrates between monosaccharides and polysaccharides. They can be extracted directly from natural products by physicochemical methods or obtained by chemical synthesis or enzymatic reaction. Oligosaccharides have important physicochemical and physiological properties. Their research and production involve many disciplines such as medicine, chemical industry, and biology. Functional oligosaccharides, as an excellent functional food base, can be used as dietary fibrer and prebiotics to enrich the diet; improve the microecology of the gut; exert antitumour, anti-inflammatory, antioxidant, and lipid-lowering properties. Therefore, the industrial applications of oligosaccharides have increased rapidly in the past few years. It has great prospects in the field of food and medicinal chemistry. This review summarized the preparation, structural features and biological activities of oligosaccharides, with particular emphasis on the application of functional oligosaccharides in the food industry and human nutritional health. It aims to inform further research and development of oligosaccharides and food chemistry.

Difference in the Intestinal Microbiota between Breastfeed Infants and Infants Fed with Artificial Milk: A Systematic Review

The gut microbiota (GM) plays a crucial role in human health, particularly during the first years of life. Differences in GM between breastfed and formula (F)-fed infants may influence long-term health outcomes. This systematic review aims to compare the gut microbiota of breastfed infants with that of F-fed infants and to evaluate the clinical implications of these differences. We searched databases on Scopus, Web of Science, and Pubmed with the following keywords: "gut microbiota", "gut microbiome", and "neonatal milk". The inclusion criteria were articles relating to the analysis of the intestinal microbiome of newborns in relation to the type of nutrition, clinical studies or case series, excluding reviews, meta-analyses, animal models, and in vitro studies. The screening phase ended with the selection of 13 publications for this work. Breastfed infants showed higher levels of beneficial bacteria such as Bifidobacterium and Lactobacillus, while F-fed infants had a higher prevalence of potentially pathogenic bacteria, including Clostridium difficile and Enterobacteriaceae. Infant feeding type influences the composition of oral GM significantly. Breastfeeding promotes a healthier and more diverse microbial ecosystem, which may offer protective health benefits. Future research should explore strategies to improve the GM of F-fed infants and understand the long-term health implications.

Post Natal Microbial and Metabolite Transmission: The Path from Mother to Infant

The entero-mammary pathway is a specialized route that selectively translocates bacteria to the newborn's gut, playing a crucial role in neonatal development. Previous studies report shared bacterial and archaeal taxa between human milk and neonatal intestine. However, the functional implications for neonatal development are not fully understood due to limited evidence. This study aimed to identify and characterize the microbiota and metabolome of human milk, mother, and infant stool samples using high-throughput DNA sequencing and FT-ICR MS methodology at delivery and 4 months post-partum. Twenty-one mothers and twenty-five infants were included in this study. Our results on bacterial composition suggest vertical transmission of bacteria through breastfeeding, with major changes occurring during the first 4 months of life. Metabolite chemical characterization sheds light on the growing complexity of the metabolites. Further data integration and network analysis disclosed the interactions between different bacteria and metabolites in the biological system as well as possible unknown pathways. Our findings suggest a shared bacteriome in breastfed mother-neonate pairs, influenced by maternal lifestyle and delivery conditions, serving as probiotic agents in infants for their healthy development. Also, the presence of food biomarkers in infants suggests their origin from breast milk, implying selective vertical transmission of these features.

Preventive effect of prenatal maternal oral probiotic supplementation on neonatal jaundice (POPS Study): A protocol for the randomised double-blind placebo-controlled clinical trial

INTRODUCTION

Neonatal jaundice is a common and life-threatening health problem in neonates due to overaccumulation of circulating unconjugated bilirubin. Gut flora has a potential influence on bilirubin metabolism. The infant gut microbiome is commonly copied from the maternal gut. During pregnancy, due to changes in dietary habits, hormones and body weight, maternal gut dysbiosis is common, which can be stabilised by probiotics supplementation. However, whether probiotic supplements can reach the baby through the mother and reduce the incidence of neonatal jaundice has not been studied yet. Therefore, we aim to evaluate the effect of prenatal maternal probiotic supplementation on the incidence of neonatal jaundice.

METHODS AND ANALYSIS

This is a randomised double-blind placebo-controlled clinical trial among 94 pregnant women (47 in each group) in a tertiary hospital in Hong Kong. Voluntary eligible participants will be recruited between 28 and 35 weeks of gestation. Computer-generated randomisation and allocation to either the intervention or control group will be carried out. Participants will take either one sachet of Vivomixx (450 billion colony-forming units per sachet) or a placebo per day until 1 week post partum. Neither the study participants nor researchers will know the randomisation and allocation. The intervention will be initiated at 36 weeks of gestation. Neonatal bilirubin level will be measured to determine the primary outcome (hyperbilirubinaemia) while the metagenomic microbiome profile of breast milk and maternal and infant stool samples as well as pregnancy outcomes will be secondary outcomes. Binary logistic and linear regressions will be carried out to assess the association of the microbiome data with different clinical outcomes.

ETHICS AND DISSEMINATION

Ethics approval is obtained from the Joint CUHK-NTEC Clinical Research Ethics Committee, Hong Kong (CREC Ref: 2023.100-T). Findings will be published in peer-reviewed journals and presented at international conferences.

TRIAL REGISTRATION NUMBER

NCT06087874.

Residents or Tourists: Is the Lactating Mammary Gland Colonized by Residential Microbiota?

The existence of the human milk microbiome has been widely recognized for almost two decades, with many studies examining its composition and relationship to maternal and infant health. However, the richness and viability of the human milk microbiota is surprisingly low. Given that the lactating mammary gland houses a warm and nutrient-rich environment and is in contact with the external environment, it may be expected that the lactating mammary gland would contain a high biomass microbiome. This discrepancy raises the question of whether the bacteria in milk come from true microbial colonization in the mammary gland ("residents") or are merely the result of constant influx from other bacterial sources ("tourists"). By drawing together data from animal, in vitro, and human studies, this review will examine the question of whether the lactating mammary gland is colonized by a residential microbiome.

Human Milk Microbiome-A Review of Scientific Reports

One of the most important bioactive components of breast milk are free breast milk oligosaccharides, which are a source of energy for commensal intestinal microorganisms, stimulating the growth of Bifidobacterium, Lactobacillus, and Bacteroides in a child's digestive tract. There is some evidence that maternal, perinatal, and environmental-cultural factors influence the modulation of the breast milk microbiome. This review summarizes research that has examined the composition of the breast milk microbiome and the factors that may influence it. The manuscript highlights the potential importance of the breast milk microbiome for the future development and health of children. The origin of bacteria in breast milk is thought to include the mother's digestive tract (entero-mammary tract), bacterial exposure to the breast during breastfeeding, and the retrograde flow of breast milk from the infant's mouth to the woman's milk ducts. Unfortunately, despite increasingly more precise methods for assessing microorganisms in human milk, the topic of the human milk microbiome is still quite limited and requires scientific research that takes into account various conditions.

Bovine milk microbiota: Key players, origins, and potential contributions to early-life gut development

BACKGROUND

Bovine milk is a significant substitute for human breast milk and holds great importance in infant nutrition and health. Apart from essential nutrients, bovine milk also contains bioactive compounds, including a microbiota derived from milk itself rather than external sources of contamination.

AIM OF REVIEW

Recognizing the profound impact of bovine milk microorganisms on future generations, our review focuses on exploring their composition, origins, functions, and applications.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Some of the primary microorganisms found in bovine milk are also present in human milk. These microorganisms are likely transferred to the mammary gland through two pathways: the entero-mammary pathway and the rumen-mammary pathway. We also elucidated potential mechanisms by which milk microbiota contribute to infant intestinal development. The mechanisms include the enhancing of the intestinal microecological niche, promoting the maturation of immune system, strengthening the intestinal epithelial barrier function, and interacting with milk components (e.g., oligosaccharides) via cross-feeding effect. However, given the limited understanding of bovine milk microbiota, further studies are necessary to validate hypotheses regarding their origins and to explore their functions and potential applications in early intestinal development.

Beliefs and views of breastfeeding mothers regarding human milk banking: A qualitative study

OBJECTIVE

The aim of the study was to determine the beliefs and opinions of breastfeeding mothers about human milk banking.

METHODS

This study was conducted as a case study, which is a qualitative research method. The population researched consisted of women who applied to the Gaziantep Health Care Family Health Center between June and December 2022. The sample included 30 mothers selected through purposive sampling. The data were collected using a descriptive characteristics form and a semistructured interview form. Ethical committee and institutional approvals were obtained. The data were analyzed using the MAXQDA qualitative research software program.

RESULTS

The majority of the breastfeeding mothers had limited knowledge about human milk banking and considered it religiously problematic. They held the belief that breastfeeding siblings should not marry each other on religious grounds. The mothers were willing to act as wet nurses in case of necessity, but they expressed a preference against having their own baby nursed by another woman. They also stated that they would consider using milk banks only if the information provided was limited to the mother and baby. Additionally, it was observed that if they found themselves in a difficult situation, they would only seek a wet nurse from their immediate social circle.

CONCLUSION

The breastfeeding mothers expressed that milk banking was a beneficial practice; however, they had religious reservations about it. It was observed that they would be willing to donate their milk to these banks and use them in times of need under certain conditions. These conditions included ensuring that the milk is not mixed, providing information about the mother and baby to families, having babies of the same sex, and adhering to strict cleanliness and hygiene measures.

An optimized culturomics strategy for isolation of human milk microbiota

Viable microorganisms and a diverse microbial ecosystem found in human milk play a crucial role in promoting healthy immune system and shaping the microbial community in the infant's gut. Culturomics is a method to obtain a comprehensive repertoire of human milk microbiota. However, culturomics is an onerous procedure, and needs expertise, making it difficult to be widely implemented. Currently, there is no efficient and feasible culturomics method specifically designed for human milk microbiota yet. Therefore, the aim of this study was to develop a more efficient and feasible culturomics method specifically designed for human milk microbiota. We obtained fresh samples of human milk from healthy Chinese mothers and conducted a 27-day enrichment process using blood culture bottles. Bacterial isolates were harvested at different time intervals and cultured on four different types of media. Using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis, we identified a total of 6601 colonies and successfully obtained 865 strains, representing 4 phyla, 21 genera, and 54 species. By combining CBA and MRS media, we were able to cultivate over 94.4% of bacterial species with high diversity, including species-specific microorganisms. Prolonged pre-incubation in blood culture bottles significantly increased the number of bacterial species by about 33% and improved the isolation efficiency of beneficial bacteria with low abundance in human milk. After optimization, we reduced the pre-incubation time in blood culture bottles and selected optimal picking time-points (0, 3, and 6 days) at 37°C. By testing 6601 colonies using MALDI-TOF MS, we estimated that this new protocol could obtain more than 90% of bacterial species, reducing the workload by 57.0%. In conclusion, our new culturomics strategy, which involves the combination of CBA and MRS media, extended pre-incubation enrichment, and optimized picking time-points, is a feasible method for studying the human milk microbiota. This protocol significantly improves the efficiency of culturomics and allows for the establishment of a comprehensive repertoire of bacterial species and strains in human milk.

2'-Fucosyllactose restores the intestinal mucosal barrier in ulcerative colitis by inhibiting STAT3 palmitoylation and phosphorylation

BACKGROUND & AIMS

2'-Fucosyllactose (2'-FL), the primary constituent of human milk oligosaccharides, has been identified as a potential regulator of inflammation in inflammatory bowel disease. Despite this recognition, the specific mechanisms through which 2'-FL alleviates ulcerative colitis (UC) remain ambiguous. This study seeks to investigate the potential anti-inflammatory properties of 2'-FL concerning intestinal inflammation and uncover the associated mechanisms.

METHODS

C57BL/6J mice were orally administered a daily dose of 500 mg/kg 2'-FL for 11 consecutive days, followed by the induction of colitis using 3 % (wt/vol) dextran sulfate sodium (DSS) for the final 6 days. Subsequently, a comprehensive range of techniques, including an Acyl-biotin exchange assay, fluorescein-isothiocyanate-labeled dextran assay, histopathology, ELISA, quantitative real-time PCR, Western blot, immunofluorescence staining, immunohistochemistry staining, Alcian blue-periodic acid schiff staining, TdT-mediated dUTP nick end labeling, transmission electron microscopy, iTRAQ quantitative proteomics, bioinformatics analysis, and the generation of signal transducer and activator of transcription 3 (STAT3) knockout mice, were employed to explore the relevant molecular mechanisms.

RESULTS

Administration of 2'-FL significantly ameliorated DSS-induced colitis in mice and enhanced the integrity of the intestinal mucosal barrier. 2'-FL downregulated the phosphorylation of STAT3 and inhibited STAT3-related signaling pathways in colon tissues, which, in turn, reduced inflammatory responses. Interestingly, knockdown of STAT3 attenuated the protective effects of 2'-FL, highlighting that 2'-FL-mediated inflammatory attenuation is dependent on STAT3 expression. Additionally, 2'-FL could influence STAT3 activation by modulating the palmitoylation and depalmitoylation of STAT3.

CONCLUSIONS

2'-FL promotes the recovery of the intestinal mucosal barrier and suppresses inflammation in ulcerative colitis by inhibiting the palmitoylation and phosphorylation of STAT3.

Screening competition and cross-feeding interactions during utilization of human milk oligosaccharides by gut microbes

Background: The infant gut microbiome is a complex community that influences short- and long-term health. Its assembly and composition are governed by variables such as the feeding type. Breast milk provides infants an important supply of human milk oligosaccharides (HMO), a broad family of carbohydrates comprising neutral, fucosylated, and sialylated molecules. There is a positive association between HMOs and the overrepresentation of Bifidobacterium species in the infant gut, which is sustained by multiple molecular determinants present in the genomes of these species. Infant-gut-associated Bifidobacterium species usually share a similar niche and display similar HMO inclinations, suggesting they compete for these resources. There is also strong evidence of cross-feeding interactions between HMO-derived molecules and bifidobacteria. Methods: In this study, we screened for unidirectional and bidirectional interactions between Bifidobacterium and other species using individual HMO. Bifidobacterium bifidum and Bacteroides thetaiotaomicron increased the growth of several other species when their supernatants were used, probably mediated by the partial degradation of HMO. In contrast, Bifidobacterium longum subsp. infantis. supernatants did not exhibit positive growth. Results: Bifidobacterium species compete for lacto-N-tetraose, which is associated with reduced bidirectional growth. The outcome of these interactions was HMO-dependent, in which the two species could compete for one substrate but cross-feed on another. 2'-fucosyllactose and lacto-N-neotetraose are associated with several positive interactions that generally originate from the partial degradation of these HMOs. Conclusion: This study presents evidence for complex interactions during HMO utilization, which can be cooperative or competitive, depending on the nature of the HMO. This information could be useful for understanding how breast milk supports the growth of some Bifidobacterium species, shaping the ecology of this important microbial community.

Gastrointestinal barrier function, immunity, and neurocognition: The role of human milk oligosaccharide (hMO) supplementation in infant formula

Breastmilk is seen as the gold standard for infant nutrition as it provides nutrients and compounds that stimulate gut barrier, immune, and brain development to the infant. However, there are many instances where it is not possible for an infant to be fed with breastmilk, especially for the full 6 months recommended by the World Health Organization. In such instances, infant formula is seen as the next best approach. However, infant formulas do not contain human milk oligosaccharides (hMOs), which are uniquely present in human milk as the third most abundant solid component. hMOs have been linked to many health benefits, such as the development of the gut microbiome, the immune system, the intestinal barrier, and a healthy brain. This paper reviews the effects of specific hMOs applied in infant formula on the intestinal barrier, including the not-often-recognized intestinal alkaline phosphatase system that prevents inflammation. Additionally, impact on immunity and the current proof for effects in neurocognitive function and the corresponding mechanisms are discussed. Recent studies suggest that hMOs can alter gut microbiota, modulate intestinal immune barrier function, and promote neurocognitive function. The hMOs 2'-fucosyllactose and lacto-N-neotetraose have been found to have positive effects on the development of infants and have been deemed safe for use in formula. However, their use has been limited due to their cost and complexity of synthesis. Thus, although many benefits have been described, complex hMOs and combinations of hMOs with other oligosaccharides are the best approach to stimulate gut barrier, immune, and brain development and for the prevention of disease.

Effects of human donor milk on gut barrier function and inflammation: in vitro study of the beneficial properties to the newborn

Introduction

The gastrointestinal and immune systems of premature infants are not fully developed, rendering them more vulnerable to severe complications like necrotizing enterocolitis. Human milk offers a rich array of bioactive factors that collectively contribute to reducing the incidence of gut infections and inflammatory conditions. When a mother's milk is unavailable, preterm infants are often provided with donor human milk processed in Human Milk Banks. However, it remains uncertain whether pasteurized milk confers the same level of risk reduction as unprocessed milk. This uncertainty may stem from the well-documented adverse effects of heat treatment on milk composition. Yet, our understanding of the comprehensive impact on protective mechanisms is limited.

Methods

In this study, we conducted a comparative analysis of the effects of raw versus pasteurized milk and colostrum versus mature milk on cellular functions associated with the gut epithelial barrier and responses to inflammatory stimuli. We utilized THP-1 and HT-29 cell lines, representing monocyte/macrophages and gut epithelial cells, respectively.

Results

Our observations revealed that all milk types stimulated epithelial cell proliferation. However, only raw colostrum increased cell migration and interfered with the interaction between E. coli and epithelial cells. Furthermore, the response of epithelial and macrophage cells to lipopolysaccharide (LPS) was enhanced solely by raw colostrum, with a milder effect observed with mature milk. In contrast, both raw and pasteurized milk diminished the LPS induced response in monocytes. Lastly, we examined how milk affected the differentiation of monocytes into macrophages, finding that milk reduced the subsequent inflammatory response of macrophages to LPS.

Discussion

Our study sheds light on the impact of human milk on certain mechanisms that potentially account for its protective effects against necrotizing enterocolitis, highlighting the detrimental influence of pasteurization on some of these mechanisms. Our findings emphasize the urgency of developing alternative pasteurization methods to better preserve milk properties. Moreover, identifying the key components critically affected by these protective mechanisms could enable their inclusion in donor milk or formula, thereby enhancing immunological benefits for vulnerable newborns.

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.

The First 1000 Days of Life: How Changes in the Microbiota Can Influence Food Allergy Onset in Children

BACKGROUND

Allergic disease, including food allergies (FA)s, has been identified as a major global disease. The first 1000 days of life can be a "window of opportunity" or a "window of susceptibility", during which several factors can predispose children to FA development. Changes in the composition of the gut microbiota from pregnancy to infancy may play a pivotal role in this regard: some bacterial genera, such as Lactobacillus and Bifidobacterium, seem to be protective against FA development. On the contrary, Clostridium and Staphylococcus appear to be unprotective.

METHODS

We conducted research on the most recent literature (2013-2023) using the PubMed and Scopus databases. We included original papers, clinical trials, meta-analyses, and reviews in English. Case reports, series, and letters were excluded.

RESULTS

During pregnancy, the maternal diet can play a fundamental role in influencing the gut microbiota composition of newborns. After birth, human milk can promote the development of protective microbial species via human milk oligosaccharides (HMOs), which play a prebiotic role. Moreover, complementary feeding can modify the gut microbiota's composition.

CONCLUSIONS

The first two years of life are a critical period, during which several factors can increase the risk of FA development in genetically predisposed children.

"Better start": promoting breastfeeding through demarketing

BACKGROUND

This paper explores how demarketing strategies impact women's breastfeeding attitudes, intentions, and behaviors under the moderation of time pressure and breastfeeding knowledge.

METHODS

A cross-sectional questionnaire-based survey among 369 respondents is used to test the proposed hypotheses. The study's population includes all breastfeeding women in Palestine. Snowball and convenience sampling were used to choose study participants through personal connections and social media. Every respondent was encouraged to share the survey with their social media contacts.

RESULTS

The data results confirm the positive effects of promotion, place, price, and product demarketing, respectively, on women's attitudes, intentions, and behavior toward breastfeeding. These effects were reinforced by reduction in time pressure and breastfeeding knowledge. Furthermore, demarketing effects are stronger for younger, more educated, unemployed, and lower-income women.

CONCLUSION

The study is a primer on promoting breastfeeding instead of formula by means of demarketing strategies.

Genetic strategies for sex-biased persistence of gut microbes across human life

Although compositional variation in the gut microbiome during human development has been extensively investigated, strain-resolved dynamic changes remain to be fully uncovered. In the current study, shotgun metagenomic sequencing data of 12,415 fecal microbiomes from healthy individuals are employed for strain-level tracking of gut microbiota members to elucidate its evolving biodiversity across the human life span. This detailed longitudinal meta-analysis reveals host sex-related persistence of strains belonging to common, maternally-inherited species, such as Bifidobacterium bifidum and Bifidobacterium longum subsp. longum. Comparative genome analyses, coupled with experiments including intimate interaction between microbes and human intestinal cells, show that specific bacterial glycosyl hydrolases related to host-glycan metabolism may contribute to more efficient colonization in females compared to males. These findings point to an intriguing ancient sex-specific host-microbe coevolution driving the selective persistence in women of key microbial taxa that may be vertically passed on to the next generation.

Factors associated with exclusive breastfeeding in Israel during the COVID-19 pandemic: a subset of the IMAgiNE EURO cross-sectional study

BACKGROUND

Evidence has shown that restrictions during the COVID-19 pandemic have negatively affected breastfeeding support and outcomes in hospitals in many countries. The aims of the study were to describe exclusive breastfeeding rates and identify factors associated with exclusive breastfeeding at hospital discharge among women who gave birth during the COVID-19 pandemic in Israel.

METHODS

A cross-sectional online anonymous survey based on WHO standards for improving quality of maternal and newborn care in health facilities was conducted among a sample of women who gave birth to a healthy singleton infant in Israel during the pandemic (between March 2020 and April 2022). The socio-ecological approach was employed to examine intrapersonal, interpersonal, organizational, and community/society factors associated with exclusive breastfeeding at hospital discharge according to women perspectives.

RESULTS

Among the 235 Israeli participants, 68.1% exclusively breastfed, 27.7% partially breastfed, and 4.2% did not breastfeed at discharge. Results of the adjusted logistic regression model showed that factors significantly associated with exclusive breastfeeding were the intrapersonal factor of multiparity (adjusted OR 2.09; 95% Confidence Interval 1.01,4.35) and the organizational factors of early breastfeeding in the first hour (aOR 2.17; 95% CI 1.06,4.45), and rooming-in (aOR 2.68; 95% CI 1.41,5.07).

CONCLUSIONS

Facilitating early breastfeeding initiation and supporting rooming-in are critical to promoting exclusive breastfeeding. These factors, reflecting hospital policies and practices, along with parity, are significantly associated with breastfeeding outcomes and highlight the influential role of the maternity environment during the COVID-19 pandemic. Maternity care in hospitals should follow evidence-based breastfeeding recommendations also during the pandemic, promoting early exclusive breastfeeding and rooming-in among all women, with particular attention to providing lactation support to primiparous women.

TRIAL REGISTRATION

Clinical Trials NCT04847336.

The Impact of the Human Milk Microbiota in the Prevention of Disease and Infant Health

Background: Human milk is recognized as an ideal food for newborns and infants owing to the presence of various nutritive factors, including healthy bacteria. Aim/Objective: This review aimed to understand the effects of human milk microbiota in both the prevention of disease and the health of infants. Methods: Data were obtained from PubMed, Scopus, Web of Science, clinical trial registries, Dergipark, and Türk Atıf Dizini up to February 2023 without language restrictions. Results: It is considered that the first human milk microbiota ingested by the newborn creates the initial microbiome of the gut system, which in turn influences the development and maturation of immunity. Bacteria present in human milk modulate the anti-inflammatory response by releasing certain cytokines, protecting the newborn against certain infections. Therefore, certain bacterial strains isolated from human milk could serve as potential probiotics for various therapeutic applications. Conclusions: In this review, the origin and significance of human milk bacteria have been highlighted along with certain factors influencing the composition of human milk microbiota. In addition, it also summarizes the health benefits of human milk as a protective agent against certain diseases and ailments.

Human Milk Microbiota Profile Affected by Prematurity in Argentinian Lactating Women

To study (16S rRNA-sequencing) the impact of gestational and corrected ages on the microbiota profile of human milk (HM) of mothers that delivered full-term and pre-term children, HM samples were obtained and classified according to the gestational age as group T (full-term births ≥37 weeks), and group P (pre-term births <37 weeks). Group P was longitudinally followed, and the samples were collected at the full-term corrected gestational age: when the chronological age plus the gestational age were ≥37 weeks (PT group). The HM microbiota composition differed depending on the gestational age (T vs. P). Group T had lower levels of Staphylococcus and higher levels of Rothia and Streptococcus, as compared to group P. The alpha Simpson diversity value was higher in group T than in P, whereas no differences were found between groups T and PT, suggesting a microbial evolution of the composition of group P towards group T over chronological age. Full-term delivery was associated with a greater diversity of microbes in HM. The microbial composition of pre-term HM, at the corrected age, did not show significant differences, as compared to the samples obtained from the full-term group, suggesting that it would be appropriate to consider the corrected age in terms of the composition and the diversity of the milk in future studies.

Evidence for human milk as a biological system and recommendations for study design-a report from "Breastmilk Ecology: Genesis of Infant Nutrition (BEGIN)" Working Group 4

Human milk contains all of the essential nutrients required by the infant within a complex matrix that enhances the bioavailability of many of those nutrients. In addition, human milk is a source of bioactive components, living cells and microbes that facilitate the transition to life outside the womb. Our ability to fully appreciate the importance of this matrix relies on the recognition of short- and long-term health benefits and, as highlighted in previous sections of this supplement, its ecology (i.e., interactions among the lactating parent and breastfed infant as well as within the context of the human milk matrix itself). Designing and interpreting studies to address this complexity depends on the availability of new tools and technologies that account for such complexity. Past efforts have often compared human milk to infant formula, which has provided some insight into the bioactivity of human milk, as a whole, or of individual milk components supplemented with formula. However, this experimental approach cannot capture the contributions of the individual components to the human milk ecology, the interaction between these components within the human milk matrix, or the significance of the matrix itself to enhance human milk bioactivity on outcomes of interest. This paper presents approaches to explore human milk as a biological system and the functional implications of that system and its components. Specifically, we discuss study design and data collection considerations and how emerging analytical technologies, bioinformatics, and systems biology approaches could be applied to advance our understanding of this critical aspect of human biology.

Programming Factors of Neonatal Intestinal Dysbiosis as a Cause of Disease

The intestinal microbiota consists of trillions of bacteria, viruses, and fungi that achieve a perfect symbiosis with the host. They perform immunological, metabolic, and endocrine functions in the body. The microbiota is formed intrauterine. Dysbiosis is a microbiome disorder characterized by an imbalance in the composition of the microbiota, as well as changes in their functional and metabolic activities. The causes of dysbiosis include improper nutrition in pregnant women, hormone therapy, the use of drugs, especially antibiotics, and a lack of exposure to the mother's vaginal microbiota during natural birth. Changes in the intestinal microbiota are increasingly being identified in various diseases, starting in the early neonatal period into the adult period. Conclusions: In recent years, it has become more and more obvious that the components of the intestinal microbiota are crucial for the proper development of the immune system, and its disruption leads to disease.

Necrotizing enterocolitis in premature infants-A defect in the brakes? Evidence from clinical and animal studies

A key aspect of postnatal intestinal adaptation is the establishment of symbiotic relationships with co-evolved gut microbiota. Necrotizing enterocolitis (NEC) is the most severe disease arising from failure in postnatal gut adaptation in premature infants. Although pathological activation of intestinal Toll-like receptors (TLRs) is believed to underpin NEC pathogenesis, the mechanisms are incompletely understood. We postulate that unregulated aberrant TLR activation in NEC arises from a failure in intestinal-specific mechanisms that tamponade TLR signaling (the brakes). In this review, we discussed the human and animal studies that elucidate the developmental mechanisms inhibiting TLR signaling in the postnatal intestine (establishing the brakes). We then evaluate evidence from preclinical models and human studies that point to a defect in the inhibition of TLR signaling underlying NEC. Finally, we provided a framework for the assessment of NEC risk by screening for signatures of TLR signaling and for NEC prevention by TLR-targeted therapy in premature infants.

Effects of Human Milk Oligosaccharides in Infant Health Based on Gut Microbiota Alteration

The primary active components of breast milk are human milk oligosaccharides (HMOs). HMOs provide many benefits to infants, including regulating their metabolism, immune system, and brain development. Recent studies have emphasized that HMOs act as prebiotics by the metabolism of intestinal microorganisms to produce short-chain fatty acids, which are crucial for infant development. In addition, HMOs with different structural characteristics can form different microbial compositions. HMOs-induced predominant microbes, including Bifidobacterium infantis, B. bifidum, B. breve, and B. longum, and their metabolites demonstrated pertinent health-promoting properties. Meanwhile, HMOs could also directly reduce the occurrence of diseases through the effects of preventing pathogen infection. In this review, we address the probable function of HMOs inside the HMOs-gut microbiota-infant network, by describing the physiological functions of HMOs and the implications of diet on the HMOs-gut microbiota-infant network.

Benefits of breastfeedinig for mother and child

Breastfeeding is the best way to feed a child from the first six months until the end of the second year. The unbreakable bond during pregnancy between a mother and her child continues during the lactation process, providing numerous benefits for both the mother and the child. Due to the effects of many hormones after childbirth, lactation offers numerous advantages for the mother. Oxytocin causes reduction of the uterus and bleeding, absence of menstruation, faster return of body weight, lower risk of cancer of the reproductive organs, and prevents the occurrence of osteoporosis and the development of the metabolic syndrome. Breastfeeding certainly ensures a better emotional bond with the child. Specificity in the composition of human milk provides the newborn with short-term and long-term protective effects. Thanks to human oligosaccharides, immunoglobulins, and polyunsaturated fatty acids that influence the composition of the microbiome of the newborn's intestine, as well as the formation of its immune response, breastfed children suffer less from respiratory and digestive infections, food allergies, autoimmune diseases and have been proven to have a higher IQ. Breastfeeding is the best form of feeding for mother and child. The specificity of the composition of human milk ensures optimal growth and development of the child and a healthier life for its mother.