Infant Gastrointestinal Microbiota Research Articles

P20-016-23 Effects of an Apiaceous or Cruciferous Vegetable on the Infant Gastrointestinal Microbiota and MicroRNA Expression: A Randomized Control Feasibility Trial

P20-016-23 Effects of an Apiaceous or Cruciferous Vegetable on the Infant Gastrointestinal Microbiota and MicroRNA Expression: A Randomized Control Feasibility Trial

A specific synbiotic-containing amino acid-based formula restores gut microbiota in non-IgE mediated cow\u2019s milk allergic infants: a randomized controlled trial

BackgroundAltered gut microbiota is implicated in cow’s milk allergy (CMA) and differs markedly from healthy, breastfed infants. Infants who suffer from severe CMA often rely on cow’s milk protein avoidance and, when breastfeeding is not possible, on specialised infant formulas such as amino-acid based formulas (AAF). Herein, we report the effects of an AAF including specific synbiotics on oral and gastrointestinal microbiota of infants with non-IgE mediated CMA with reference to healthy, breastfed infants.MethodsIn this prospective, randomized, double-blind controlled study, infants with suspected non-IgE mediated CMA received test or control formula. Test formula was AAF with synbiotics (prebiotic fructo-oligosaccharides and probiotic Bifidobacterium breve M-16V). Control formula was AAF without synbiotics. Healthy, breastfed infants were used as a separate reference group (HBR). Bacterial compositions of faecal and salivary samples were analysed by 16S rRNA-gene sequencing. Faecal analysis was complemented with the analysis of pH, short-chain fatty acids (SCFAs) and lactic acids.ResultsThe trial included 35 test subjects, 36 controls, and 51 HBR. The 16S rRNA-gene sequencing revealed moderate effects of test formula on oral microbiota. In contrast, the gut microbiota was substantially affected across time comparing test with control. In both groups bacterial diversity increased over time but was characterised by a more gradual increment in test compared to control. Compositionally this reflected an enhancement of Bifidobacterium spp. and Veillonella sp. in the test group. In contrast, the control-fed infants showed increased abundance of adult-like species, mainly within the Lachnospiraceae family, as well as within the Ruminococcus and Alistipes genus. The effects on Bifidobacterium spp. and Lachnospiraceae spp. were previously confirmed through enumeration by fluorescent in situ hybridization and were shown for test to approximate the proportions observed in the HBR. Additionally, microbial activity was affected as evidenced by an increase of l-lactate, a decrease of valerate, and reduced concentrations of branched-chain SCFAs in test versus control.ConclusionsThe AAF including specific synbiotics effectively modulates the gut microbiota and its metabolic activity in non-IgE mediated CMA infants bringing it close to a healthy breastfed profile.Trial registration Registered on 1 May 2013 with Netherlands Trial Register Number NTR3979.

Characterization of microbial communities in the chicken oviduct and the origin of chicken embryo gut microbiota

The transferred microbiota from mother to baby constitutes the initial infant gastrointestinal microbiota and has an important influence on the development and health of infants in human. However, the reproductive tract microbiota of avian species and its inheritance have rarely been studied. We aimed to characterize the microbial community in the chicken reproductive tract and determine the origin of the chicken embryo gut microbiota. Microbiota in four different portions of chicken oviduct were determined using 16S rRNA metagenomic approach with the IonTorrent platform. Additionally, we analyzed the mother hen’s magnum and cloaca, descendent egg, and embryo gut microbiota. The microbial composition and relative abundance of bacterial genera were stable throughout the entire chicken reproductive tract, without significant differences between the different parts of the oviduct. The chicken reproductive tract showed a relatively high abundance of Lactobacillus species. The number of bacterial species in the chicken reproductive tract significantly increased following sexual maturation. Core genera analysis detected 21 of common genera in the maternal magnum and cloaca, descendent egg shell, egg white, and embryo gut. Some elements of the maternal oviduct microbiota appear to be transferred to the embryo through the egg white and constitute most of the embryo gut bacterial population.

Profiling of Sialylated Oligosaccharides in Mammalian Milk Using Online Solid Phase Extraction-Hydrophilic Interaction Chromatography Coupled with Negative-Ion Electrospray Mass Spectrometry.

Sialylated oligosaccharides are important components in mammalian milk. They play a key role in the health and growth of infants by helping to shape up infant's gastrointestinal microbiota and defense against infection by various pathogenic agents. A detailed knowledge of the structures, compositions, and quantities of the sialylated milk oligosaccharides (SMOs) is a prerequisite for understanding their biological roles. However, because of the presence of very large amounts of lactose and neutral oligosaccharides, accurate analysis of SMOs is difficult. A pretreatment step is required to remove lactose and neutral oligosaccharides but conventional off-line pretreatment methods are time-consuming and of poor reproducibility. In this presentation, we linked solid-phase extraction (SPE) with hydrophilic interaction chromatography (HILIC) followed by mass spectrometry (MS) identification for the analysis of SMOs. A SPE column with electrostatic repulsion function was used for removal of lactose and neutral oligosaccharides, a HILIC analytical column for separation of the SMOs, and negative-ion electrospray ionization tandem MS was used for their identification and sequencing. The success of the established online SPE-HILIC-MS method was demonstrated by profiling of SMOs in human to investigate detailed SMO changes during lactation period and in animals to compare the difference in SMO contents among the different species.

Association of Chorioamnionitis with Aberrant Neonatal Gut Colonization and Adverse Clinical Outcomes.

ObjectiveChorioamnionitis (inflammation of the placenta and fetal membranes) and abnormal gastrointestinal colonization have been associated with an increased risk of sepsis and death in preterm infants, but whether chorioamnionitis causes abnormal pioneering gastrointestinal colonization in infants is not known. We determined the relationship between chorioamnionitis, altered infant fecal microbiome indicating abnormal gastrointestinal colonization, and adverse outcomes.Study DesignPreterm infants ≤ 28 weeks at birth were enrolled from 3 level III NICUs in Cincinnati, Ohio and Birmingham, Alabama. Sequencing for 16S microbial gene was performed on stool samples in the first 3 weeks of life. Chorioamnionitis was diagnosed by placental histology. Late onset sepsis and death outcomes were analyzed in relation to fecal microbiota and chorioamnionitis with or without funisitis (inflammation of the umbilical cord).ResultsOf the 106 enrolled infants, 48 infants had no chorioamnionitis, 32 infants had chorioamnionitis but no funisitis (AC), and 26 infants had chorioamnionitis with funisitis (ACF). The fecal samples from ACF infants collected by day of life 7 had higher relative abundance of family Mycoplasmataceae (phylum Tenericutes), genus Prevotella (phylum Bacteroidetes) and genus Sneathia (phylum Fusobacteria). Further, AC and ACF infants had higher incidence of late-onset sepsis/death as a combined outcome. Presence of specific clades in fecal samples, specifically, order Fusobacteria, genus Sneathia or family Mycoplasmataceae, were significantly associated with higher risk of sepsis or death.ConclusionThe results support the hypothesis that specific alterations in the pioneering infant gastrointestinal microbiota induced by chorioamnionitis predispose to neonatal sepsis or death.

Antagonistic activities of some Bifidobacterium sp. strains isolated from resident infant gastrointestinal microbiota on Gram-negative enteric pathogens

The gastrointestinal microbiota contributes to the consolidation of the anti-infectious barrier against enteric pathogens. The purpose of this study was to investigate the influence of Bifidobacterium sp. strains, recently isolated from infant gastrointestinal microbiota on the in vitro growth and virulence features expression of enteropathogenic bacterial strains.The antibacterial activity of twelve Bifidobacterium sp. strains isolated from human feces was examined in vitro against a wide range of Gram negative pathogenic strains isolated from 30 infant patients (3 days to 5 years old) with diarrhea. Both potential probiotic strains (Bifidobacterium longum, Bifidobacterium pseudocatenulatum, Bifidobacterium catenulatum, Bifidobacterium breve, Bifidobacterium ruminantium) and enteropathogenic strains (EPEC, EIEC, Klebsiella pneumoniae, Salmonella sp., Yersinia enterocolitica, Pseudomonas aeruginosa) were identified by MALDI-TOF and confirmed serologically when needed. The bactericidal activity, growth curve, adherence to the cellular HEp-2 substratum and production of soluble virulence factors have been assessed in the presence of different Bifidobacterium sp. cultures and fractions (whole culture and free-cell supernatants).Among the twelve Bifidobacterium sp. strains, the largest spectrum of antimicrobial activity against 9 of the 18 enteropathogenic strains was revealed for a B. breve strain recently isolated from infant intestinal feces. The whole culture and free-cell supernatant of B. breve culture decreased the multiplication rate, shortened the log phase and the total duration of the growth curve, with an earlier entrance in the decline phase and inhibited the adherence capacity to a cellular substratum and the swimming/swarming motility too. These results indicate the significant probiotic potential of the B. breve strain.

The Influence of Milk Oligosaccharides on Microbiota of Infants: Opportunities for Formulas

In addition to a nutritive role, human milk also guides the development of a protective intestinal microbiota in the infant. Human milk possesses an overabundance of complex oligosaccharides that are indigestible by the infant yet are consumed by microbial populations in the developing intestine. These oligosaccharides are believed to facilitate enrichment of a healthy infant gastrointestinal microbiota, often associated with bifidobacteria. Advances in glycomics have enabled precise determination of milk glycan structures as well as identification of the specific glycans consumed by various gut microbes. Furthermore, genomic analysis of bifidobacteria from infants has revealed specific genetic loci related to milk oligosaccharide import and processing, suggesting coevolution between the human host, milk glycans, and the microbes they enrich. This review discusses the current understanding of how human milk oligosaccharides interact with the infant microbiota and examines the opportunities for translating this knowledge to improve the functionality of infant formulas.

Human milk glycobiome and its impact on the infant gastrointestinal microbiota

Human milk glycobiome and its impact on the infant gastrointestinal microbiota

Human milk glycobiome and its impact on the infant gastrointestinal microbiota.

Human milk contains an unexpected abundance and diversity of complex oligosaccharides apparently indigestible by the developing infant and instead targeted to its cognate gastrointestinal microbiota. Recent advances in mass spectrometry-based tools have provided a view of the oligosaccharide structures produced in milk across stages of lactation and among human mothers. One postulated function for these oligosaccharides is to enrich a specific "healthy" microbiota containing bifidobacteria, a genus commonly observed in the feces of breast-fed infants. Isolated culture studies indeed show selective growth of infant-borne bifidobacteria on milk oligosaccharides or core components therein. Parallel glycoprofiling documented that numerous Bifidobacterium longum subsp. infantis strains preferentially consume small mass oligosaccharides that are abundant early in the lactation cycle. Genome sequencing of numerous B. longum subsp. infantis strains shows a bias toward genes required to use mammalian-derived carbohydrates by comparison with adult-borne bifidobacteria. This intriguing strategy of mammalian lactation to selectively nourish genetically compatible bacteria in infants with a complex array of free oligosaccharides serves as a model of how to influence the human supraorganismal system, which includes the gastrointestinal microbiota.

Development of a Six-Stage Culture System for Simulating the Gastrointestinal Microbiota of Weaned Infants

The development of a six-stage culture system simulating the microbial community present in the intestine of weaned infants is described. Plate counts of selected fecal indicator-organisms revealed high concentrations in the culture liquid of the simulator and these data paralleled those in infant feces. The metabolic patterns of the microbiota present in the model and the infant feces, compared by means of BIOLOG, revealed similar carbon utilization profiles. A genetic ? ngerprinting by means of Denaturing Gradient Gel Electrophoresis generated a more complex banding pattern in the culture system than in infant feces. The three vessels representing the colon showed similar DGGE patterns, indicating a high stability of the dominant microbial species. Yet, high variability in terms of the dominant bacteria was observed in infant stools. The fermentative capacity of the in vitro system, characterized by the concentration of volatile fatty acids and ammonium, was in accordance with the in vivo data. The enhanced production of propionate in vitro is probably due to the high concentration of fermentable sugars in the culture medium and hence, a high fermentation rate. The elevated concentration of propionate, as well as valerate and caproate in vitro suggests conditions favoring Megasphaera sp. fermentation. The data concerning microbial diversity and activity warrants further exploration of the in vitro model as a tool for studying the impact of newly developed infant formulas, functional foods and pharmaceuticals on the gastrointestinal microbiota of infants. Keywords: intestinal microbiota, gut fermentation, infant, culture system.

Development of a Six-Stage Culture System for Simulating the Gastrointestinal Microbiota of Weaned Infants

The development of a six-stage culture system simulating the microbial community present in the intestine of weaned infants is described. Plate counts of selected fecal indicator-organisms revealed high concentrations in the culture liquid of the simulator and these data paralleled those in infant feces. The metabolic patterns of the microbiota present in the model and the infant feces, compared by means of BIOLOG, revealed similar carbon utilization profiles. A genetic fingerprinting by means of Denaturing Gradient Gel Electrophoresis generated a more complex banding pattern in the culture system than in infant feces. The three vessels representing the colon showed similar DGGE patterns, indicating a high stability of the dominant microbial species. Yet, high variability in terms of the dominant bacteria was observed in infant stools. The fermentative capacity of the in vitro system, characterized by the concentration of volatile fatty acids and ammonium, was in accordance with the in vivo data. The enhanced production of propionate in vitro is probably due to the high concentration of fermentable sugars in the culture medium and hence, a high fermentation rate. The elevated concentration of propionate, as well as valerate and caproate in vitro suggests conditions favoring Megasphaera sp. fermentation. The data concerning microbial diversity and activity warrants further exploration of the in vitro model as a tool for studying the impact of newly developed infant formulas, functional foods and pharmaceuticals on the gastrointestinal microbiota of infants.