Search Results (120)

Background/Objectives: The establishment of early gut microbiota is crucial for host health. Lactoferrin (LF), which is present in breast milk, positively impacts gut microbiota composition. However, the effect of lactation LF on the establishment and composition of early gut microbiota in different disease models in adulthood remains unclear. Methods: Lactation-LF-deficient mice were established using systemically LF–knocked-out maternal mice. This study assessed the maturity of the gut microbiota in LF feeding-deficient mice in relation to age and changes in the gut microbiota in adult high-fat diet (HFD)-induced obesity, dextran sodium sulfate (DSS)-induced acute colitis, and chronic unpredictable mild stress (CUMS)-induced depression models. Results: Compared to LF intake during lactation, LF deficiency during lactation increased the abundance of potentially pathogenic bacteria in the gut, resulting in abnormal microbial maturation. LF intake during lactation aggravated gut microbiota dysbiosis induced via HFD, DSS, and CUMS in adulthood and may change the function of Enterorhabdus, GCA-900066575, Peptococcus, Tuzzerella, Akkermansia, and Desulfovibrio. Comparing the different models revealed that bacteria that were jointly upregulated via HFD and DSS exhibited increased levels of inflammation and oxidation. LF deficiency during lactation may weaken the association between an HFD and inflammatory bowel disease (IBD). The changing trends in many gut microbes caused by DSS and HFD were opposite to those that changed with age. Conclusions: Lactoferrin deficiency increases the abundance of potential pathogens and disrupts microbial maturation. This lack of LF exacerbates dysbiosis in models of obesity, colitis, and depression. Regulating the gut microbiota according to the rules of microbial succession during the maturation process of gut microbiota may improve gut microbiota dysbiosis in patients with obesity and IBD. Full article

This review explores current knowledge on the environmental, oxidative, and genomic effects of sucralose (E955), an artificial sweetener widely used in food products, including those for children, and known to cross both the placental barrier and into breast milk. Although initially considered safe, research conducted over the past two decades has presented conflicting evidence regarding its long-term impact, particularly on ecosystems and biological systems. Structurally similar to chlorinated compounds such as perfluoralkyl substances (PFAS), sucralose is highly persistent in the environment, which complicates its degradation and removal, especially from aquatic systems. Several studies have reported behavioral, metabolic, and even genomic alterations in aquatic organisms exposed to sucralose, raising concerns about its broader ecological safety. In addition, its presence has been linked to shifts in microbiota composition in both environmental and human contexts. Reports of sucralose-induced oxidative stress further highlight the need for caution in its continued use, particularly in sensitive formulations. Given its widespread presence and resistance to degradation, further investigation into the environmental and biological safety of sucralose is urgently needed. Full article

Mastitis, an inflammatory condition of the breast, significantly affects breastfeeding women and can lead to the early cessation of lactation. This article explores the pathophysiology of mastitis, distinguishing between acute mastitis (AM) and subacute mastitis (SAM), with a focus on the microbial dynamics involved. AM is primarily associated with Staphylococcus aureus, while SAM is linked to a dysbiotic milk microbiota characterized by an imbalance of microbial species, including increased levels of opportunistic pathogens. The role of inflammation and the gut–breast axis in the development of mastitis are discussed, emphasizing the importance of maintaining a healthy microbiota. Recent studies highlight the potential of probiotics as a preventive and therapeutic measure against mastitis, showing promising results in reducing incidence and recurrence. However, further research is necessary to optimize probiotic strains, dosages, and treatment protocols. This review underscores the need for a comprehensive understanding of the microbiological, immunological, and inflammatory factors involved in mastitis to develop effective prevention and treatment strategies. Full article

Cow’s milk allergy is one of the most prevalent food allergies in infancy. Exclusive breastfeeding is the recommended source of nutrition for the first six months of life, but some infants may develop cow’s milk allergy due to the transfer of milk proteins such as β-lactoglobulin through breast milk. There are still many uncertainties about cow’s milk allergy in breastfed babies. The purpose of this review is to summarize the latest findings mainly focused on immunological mechanisms and challenges in diagnosis. We pointed out which clinical signs in breastfed infants are associated with immediate IgE responses and which are linked to delayed non-IgE mechanisms or mixed IgE/non-IgE-mediated reactions. Since standard IgE tests are often useless in non-IgE cases, diagnosis typically involves dietary elimination and cow’s milk challenge. This study addresses the controversial topic of maternal elimination diets, assessing the nutritional risks to both mothers and infants in relation to their possible benefits. It has also been discussed whether the microbiota signature could be a potential factor in both tolerance development and the risk of cow’s milk allergy in early life. Overall, accurate diagnosis and personalized treatment plans are vital to prevent overdiagnosis and ensure proper growth while maintaining the practice of breastfeeding. Full article

Breast milk is vital for infant survival, protecting against infections and strengthening the immune system. In addition to nutrients, breast milk contains beneficial microorganisms, antimicrobial peptides and proteins (APPs), including lactoferrin and lysozyme, and peptides such as defensins and cathelicidins that destroy harmful bacteria and regulate the neonatal immune response. Breast milk also promotes the growth of beneficial gut bacteria (Bacteroidaceae and Bifidobacteriaceae) while reducing harmful pathogens, fostering a healthy gut microbiome, and supporting long-term infant health. Traditionally, research on antimicrobial proteins and milk microbiota has been conducted in isolation. However, at the molecular level, these components do not function independently; they interact synergistically, influencing immunomodulation, inflammation, and the composition of the gut microbiome. Therefore, this review aims to provide an overview of the discovery and identification of APPs in breast milk, the dynamic relationship between the breast milk microbiota, and the potentiation of artificial feeding with supplemented formulas when breastfeeding is impossible, benefits on newborn immune systems, and even the benefits to breast tissue. Full article

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. Full article

The human milk (HM) microbiome is variable and depends on maternal, perinatal, and cultural–environmental factors. The diversity of the HM microbiome is crucial in the development of the child. The aim of the study was to assess the prevalence of bacteria (using culture-based methods) of Polish women with normal BMI, giving birth on time through vaginal delivery. Methods: The research material consisted of human milk and swabs from the areola and nipple, before and after breastfeeding, derived from Polish women (n = 86). Classic culture methods were used to obtain multiple bacteria. Species identification of the grown colonies was performed using MALDI TOF MS (Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry). Results: 120 species of bacteria were isolated, mainly from the genus Streptococcus and Staphylococcus. Species specific only to human milk were identified (belonging to the following genera: Microbacterium, Shewanella, Psychrobacter, Aeromonas, Serratia, Buttiauxella, Lactobacillus, Bifidobacterium) as well as species specific only to areola and nipple swabs after breastfeeding (Acinetobacter lactucae, Moraxella catarrhalis, Corynebacterium pseudodiphtheriticum, Corynebacterium propinquim). It was confirmed that most species were present in all tested materials collected from one patient. Conclusions: The analysis carried out showed the presence of bacteria in the human milk of Polish women, including strains of lactic acid bacteria. The human milk microbiota may significantly influence the formation of the infant’s intestinal microbiota, including some key genera, i.e., Lactobacillus, Bifidobacterium, and Limosilactobacillus, which were also isolated from the tested samples. The data presented here provide new data on culturable bacterial species isolated from breast milk from Polish women giving birth via vaginal delivery and potential routes of transmission from the neonate’s oral cavity. Full article

Background/Objectives: Breast milk is a complex fluid crucial for infant development, nutrition, and immunological and neurodevelopmental support. Recent findings suggest that factors regarding mental health, such as stress, anxiety, and postpartum depression (PPD), may influence the composition of breast milk. This review aims to synthesize current knowledge regarding the relationship between a mother’s mental state and the biochemical profile of human milk, focusing mainly on nutrients, hormones, immune factors, and microbiota. Methods: A systematic literature search was conducted in PubMed and the Web of Science using predefined keywords related to psychological factors and milk composition. Studies involving validated psychological assessment tools and only human subjects were included, in accordance with PRISMA guidelines. Results: Findings indicated that maternal stress and PPD are associated with alterations in breast milk composition. Elevated cortisol and changes in melatonin and prolactin levels have been observed. Immune components, such as secretory immunoglobulin A and transforming growth factor beta 2, exhibit variable responses depending on stress type and duration. Lower concentrations of docosahexaenoic acid and polyunsaturated fatty acid have been observed among mothers diagnosed with depression. Additionally, maternal psychological distress may influence infants’ gut microbiota composition, potentially affecting long-term health outcomes. Conclusions: The maternal psychological state plays an essential role in shaping the composition of human breast milk. Understanding these associations highlights the need for mental health support during the postpartum period to optimize infant development. Future research should focus on the molecular mechanisms underlying these changes and potential interventions to mitigate adverse effects. Full article

The development of the human immune system starts during the fetal period in a largely, but probably not completely, sterile environment. During and after birth, the immune system is exposed to an increasingly complex microbiota. The first microbiota encountered during passage through the birth canal colonize the infant gut and induce the tolerance of the immune system. Transplacentally derived maternal IgG as well as IgA from breast milk protect the infant from infections during the first 100 days, during which the immune system further develops and immunological memory is formed. The Weaning and introduction of solid food expose the immune system to novel (food) antigens and allow for other microbiota to colonize. The cells and molecules involved in the mutual and intricate interactions between microbiota and the developing immune system are now beginning to be recognized. These include bacterial components such as polysaccharide A from Bacteroides fragilis, as well as bacterial metabolites such as the short-chain fatty acid butyrate, indole-3-aldehyde, and indole-3-propionic acid. All these, and probably more, bacterial metabolites have specific immunoregulatory functions which shape the development of the human immune system during the first 1000 days of life. Full article

Breast milk is rich in bioactive components, especially human milk oligosaccharides (HMOs), which are crucial for establishing gut microbiota. The 2′-FL (2-Fucosyllactose), one of the most abundant oligosaccharides in breast milk, functions as a selective prebiotic. Objective: To examine the effect of adding 2′-FL (2-Fucosyllactose) to an infant formula containing prebiotic galacto-oligosaccharides (GOSs) and fructo-oligosaccharides (FOSs) on the gut microbiome of healthy formula-fed infants. Methods: This study enrolled infants from three groups: an HMO experimental group (n = 29), a GOS/FOS control group (n = 30), and an exclusively breastfed (breast milk [BM]) reference group (n = 28). Fecal samples from the three groups in the first and fourth months of life were analyzed. The V3 and V4 regions of the 16S rRNA gene were amplified and sequenced on the Illumina MiSeq. ANOVA, Kruskal–Wallis, richness indices (Chao1, Shannon), UniFrac distances, and the Adonis tests were used to perform statistical analyses on the relative abundance of phyla and genera, as well as the alpha and beta-diversity of the gut microbiota. Results: After intervention, Actinobacteriota emerged as the predominant phylum in both the HMO (60.4%) and BM (46.6%) groups. Bifidobacterium and Escherichia-Shigella were identified as the two most abundant bacterial genera in both groups. Nevertheless, the statistical analysis showed that the relative abundance of Bifidobacterium in the HMO formula-fed group after intervention was similar to that in the BM group (p > 0.05). Infants in the HMO and GOS/FOS groups showed higher relative abundance of [Ruminococcus]_gnavus_group bacteria compared to those in the BM group. Groups fed with infant formula demonstrated higher alpha-diversity of gut microbiota compared to breastfed infants (p < 0.05), at the time of admission as well as after the intervention. Beta-diversity was significantly different among the three groups, according to type of feeding. Infants fed a 2′-FL-supplemented infant formula exhibited growth comparable to that of breastfed infants throughout the intervention period, demonstrating that the formula was both safe and well tolerated. Conclusions: Adding 2′-FL to an infant formula containing 4 g/L of GOS + FOS resulted in a stronger bifidogenic effect compared to the formula without 2′-FL. Full article

The calcium-binding S100B protein is concentrated in glial cells (including enteroglial cells) in the nervous system. Its conformation and amino acid composition are significantly conserved in different species; this characteristic suggests conserved biological role(s) for the protein. The biological activity is concentration-dependent: low physiological concentrations exert a neurotrophic effect, while high concentrations exert a proinflammatory/toxic role. The proinflammatory/toxic role of S100B currently attracts the scientific community’s primary attention, while the protein’s physiological action remains unraveled—yet remarkably interesting. This is now a topical issue due to the recently consolidated notion that S100B is a natural trophic nutrient available in breast milk and/or other aliments, possibly interacting with other body districts through its impact on microbiota. These recent data may offer novel clues to understanding the role of this challenging protein. Full article

The purpose of this study was to investigate the degradation mechanism of Bifidobacterium on breast milk oligosaccharides (HMOs) and its application in infant nutrition. The composition and characteristics of HMOs were introduced, and the degradation mechanism of HMOs by Bifidobacterium was described, including intracellular and extracellular digestion and species-specific differences. The interaction between Bifidobacterium and Bacteroides in the process of degrading HMOs and its effect on intestinal microecology were analyzed. The effects of HMO formula milk powder on the intestinal microbiota of infants were discussed, including simulating breast milk composition, regulating intestinal flora and immune function, infection prevention, and brain development. Finally, the research results are summarized, and future research directions are proposed to provide directions for research in the field of infant nutrition. Full article

Breast milk is a fluid of vital importance during the first stages of life of the newborn since, in addition to providing nutrients, it also contains cells and molecules of the immune system, which protect the neonate from infection and, at the same time, modulate the establishment of the microbiota. Bactericidal/permeability-increasing protein (BPI) is relevant in preventing disease and sepsis in neonates. Therefore, the following work aimed to demonstrate the presence of BPI in the different stages of breast milk and its possible immune functions. Our results demonstrate for the first time the presence of soluble BPI and leukocytes and epithelial cells containing it, primarily in the colostrum stage. Using BPI at concentrations typical of colostrum, we observed that it reduces the growth of two distinct E. coli strains, enhances the uptake of these bacteria by monocytes, and suppresses the secretion of the proinflammatory cytokine interleukin (IL)-8 in infected intestinal cells. These findings suggest that BPI transferred via colostrum from mother to newborn may play a significant role in providing antimicrobial and anti-inflammatory protection during the early stages of life. Full article

Breastfeeding is fundamental for the development and protection of the newborn, and microorganisms present in breast milk are associated with the development of the infant’s intestinal microbiota. However, there are factors that interfere with breastfeeding, resulting in the need to supply donated milk to milk banks for these children. Even though there is a restriction on medications prescribed for pregnant and breastfeeding women, some antimicrobials are accepted, as long as they are used correctly and as they can increase the selection pressure for resistant bacteria. The microorganisms present in breast milk from a human milk bank were evaluated and the resistance of the isolates to antimicrobials was phenotypically characterized. In total, 184 microbial isolates were identified by mass spectrometry, of 12 bacterial genera and 1 yeast genus. There was a high prevalence of bacteria of the genus Staphylococcus, mainly S. epidermidis (33%). Resistance to antimicrobials varied among species, with a higher percentage of isolates resistant to penicillins and macrolides. Multidrug resistance was identified in 12.6% of 143 isolates. Breast milk contains a wide variety of microorganisms, mainly those of the Staphylococcus and Enterobacter genera. There was a high percentage of resistant isolates, and multidrug resistance in Klebsiella oxytoca (66.7%; 4/6) and S. epidermidis (15.0%; 9/60) isolates, which increases the public health concern. Full article

Breastfeeding supplies nutrition, immunity, and hormonal cues to infants. Feeding expressed breast milk may result in de-phased milk production and feeding times, which distort the real-time circadian cues carried by breast milk. We hypothesized that providing expressed breast milk alters the microbiotas of both breast milk and the infant’s gut. To test this hypothesis, we analyzed the microbiota of serial breast milk and infant fecal samples obtained from 14 mother–infant dyads who were lactating, half of which were providing expressed breast milk. Infant fecal microbiota showed lower α-diversity than breast milk microbiota. Bacterial amplicon sequence variant sharing occurred between breast milk and infant feces with no feeding group differences. However, the age-dependent gain in breast milk α-diversity was only significant in the expressed breast milk group and not in the direct breastfeeding group, suggesting that decreased contact with the infant’s mouth influences the milk microbiota. Trending lower connectivity was also noted with breast milk microbes in the direct breastfeeding group, consistent with regular perturbations of the developing baby’s oral microbiota by latching on the breast. The results of this preliminary study urge further research to independently confirm the effects of providing expressed breast milk and their health significance. Full article