Early Intestinal Microbiota Research Articles

Characterization of the intestinal microbiota in MSM with HIV infection

BackgroundHIV-infected persons demonstrate notable disturbances in their intestinal microbiota; however, the impact of intestinal microbiota on HIV susceptibility in men who have sex with men (MSM), as well as the effects of HIV and antiretroviral therapy (ART) on their gut microbiota, remains under active study. Thus, our research focuses on clarifying the distinctions in intestinal microbiota composition among uninfected MSM and non-MSM healthy controls, investigating the alterations in early-stage intestinal microbial communities following HIV infection, and assessing how ART affects the intestinal microbiota.MethodsThis study enrolled four participant groups: uninfected MSM, Recent HIV-1 infection (RHI) MSM, MSM on ART, and non-MSM healthy controls, with 30 individuals in each group. We utilized 16S ribosomal DNA (16S rDNA) amplicon sequencing to analyze fecal microbiota and employed Luminex multiplex assays to measure plasma markers for microbial translocation (LBP, sCD14) and the inflammatory marker CRP.FindingsComparing uninfected MSM to non-MSM healthy controls, no substantial variances were observed in α and β diversity. Uninfected MSM had higher average relative abundances of Bacteroidetes, Prevotella, and Alloprevotella, while Bacteroides, Firmicutes, and Faecalibacterium had lower average relative abundances. MSM on ART had lower intestinal microbiota diversity than RHI MSM and uninfected MSM. In MSM on ART, Megasphaera and Fusobacterium increased, while Faecalibacterium and Roseburia decreased at genus level. Additionally, treatment with a non-nucleoside reverse transcriptase inhibitor (NNRTI) led to significant alterations in intestinal microbiota diversity and composition compared to RHI MSM. The random forest model showed that HIV infection biomarkers effectively distinguished between newly diagnosed HIV-infected MSM and HIV-negative MSM, with an ROC AUC of 76.24% (95% CI: 61.17-91.31%).ConclusionsMSM showed early intestinal microbiota imbalances after new HIV infection. MSM on ART experienced worsened dysbiosis, indicating a combined effect of HIV and ART. NNRTI-based treatment notably changed intestinal microbiota, suggesting a potential direct impact of NNRTI drugs on intestinal microbiota.

The impact of formula-fed feeding in comparison with breastfeeding to the infant’s intestinal microbiota: a literature review

Child health outcomes are related to the mother's nutrition during pregnancy and the baby's diet throughout infancy. The child's intestinal microbiome is the main source of postnatal immunological activation, which is linked to both health and disease in children. Nursing exclusively is advised for the first six months of a baby's life; otherwise, dairy-based infant formula is a supplement to breastfeeding. Numerous studies have shown that breastfed newborns have a different makeup of gut flora compared to infants fed formula. To highlight the important differences between human milk and infant formula in the development of the early intestinal microbiota and immune system, this study attempts to ignore any plausible explanations for some of the risks and benefits associated with human milk and infant formula. The approach was a literature review. A comprehensive search was done on the Pubmed Central® search engine. Using the Boolean operators "AND" and "OR," the search terms used are "breastfeeding," "formula," "microbiota," "intestinal," "human milk," and "infant." Among all the publications purchased, articles comprising various types of studies relevant to the literature review topic were picked. Breastfeeding is the preferred baby-feeding strategy. If exclusive breastfeeding is not preferred, infant formula prepared from cow's milk should be altered to promote the development of the infant's gut flora. Formulations could be modified by adding probiotic or prebiotic oligosaccharide agents.

Early intestinal microbiota changes in aged and adult mice with sepsis.

The mortality rate associated with sepsis in elderly individuals is higher than that in younger individuals. The intestinal microbiota has been demonstrated to play an important role in the occurrence and development of sepsis. The purpose of this study was to investigate the differences in the intestinal microbiota between aged and adult mice with sepsis. Thirty male C57BL mice were randomly divided into two groups: 15 in the adult group (AD group) and 15 in the age group (Age group). All the mice underwent caecal ligation and puncture to induce sepsis. Mice faeces were collected, and analysed using 16S rRNA sequencing. The liver and colon tissues were collected. There were significant differences in intestinal microbiota composition between the two groups. Compared with adult sepsis mice, the diversity of intestinal microbiota in the aged group was significantly reduced and the structure of dominant intestinal microbiota was changed. In the Age group, the microbiota associated with inflammatory factors increased, and the microbiota associated with the production of SCFAs (Ruminiclostridium, Prevotellaceae_UCG-001, Rikenella, Parabacteroides, Oscillibacter, Odoribacter, Muribaculum, Lachnoclostridium, Intestinimonas, Faecalibaculum, Anaerotruncus, Alloprevotella and Absiella) decreased. The metabolic pathways related to the microbiota also changed. Moreover, the proportion of inflammatory factors in Age group was higher than that in AD group. Our results showed that there were significant differences in the abundance and structure of microbiota between aged and adult sepsis mice, Aged sepsis mice have more severe intestinal microbiota destruction and liver tissue inflammation than adult sepsis mice.

The Maternal-Fetal Gut Microbiota Axis: Physiological Changes, Dietary Influence, and Modulation Possibilities.

The prenatal period and the first years of life have a significant impact on the health issues and life quality of an individual. The appropriate development of the immune system and the central nervous system are thought to be major critical determining events. In parallel to these, establishing an early intestinal microbiota community is another important factor for future well-being interfering with prenatal and postnatal developmental processes. This review aims at summarizing the main characteristics of maternal gut microbiota and its possible transmission to the offspring, thereby affecting fetal and/or neonatal development and health. Since maternal dietary factors are potential modulators of the maternal–fetal microbiota axis, we will outline current knowledge on the impact of certain diets, nutritional factors, and nutritional modulators during pregnancy on offspring’s microbiota and health.

Infant gut bacterial community composition and food-related manifestation of atopy in early childhood.

Background:Immunoglobulin E–mediated food allergy (IgE-FA) has emerged as a global public health concern. Immune dysregulation is an underlying mechanism for IgE-FA, caused by “dysbiosis” of the early intestinal microbiota. We investigated the association between infant gut bacterial composition and food-related atopy at age 3–5 years using a well-characterized birth cohort.Methods:The study definition of IgE-FA to egg, milk, or peanut was based on physician panel retrospective review of clinical and questionnaire data collected from birth through age 3–5 years. Using 16S rRNA sequencing, we profiled the bacterial gut microbiota present in stool specimens collected at 1 and 6 months of age.Results:Of 447 infants with data for analysis, 44 (9.8%) met physician panel review criteria for IgE-FA to ≥1 of the three allergens. Among children classified as IgE-FA at 3–5 years, infant stool samples showed significantly less diversity of the gut microbiota compared with the samples of children classified as no IgE-FA at age 3–5 years, especially for milk and peanut (all covariate-adjusted p’s for alpha metrics <.007). Testing of individual operational taxonomic units (OTUs) revealed 6-month deficiencies in 31 OTUs for IgE-FA compared with no IgE-FA, mostly in the orders Lactobacillales, Bacteroidales, and Clostridiales.Conclusions:Variations in gut microbial composition in infant stool were associated with a study definition of IgE-FA at 3–5 years of age. This included evidence of a lack of bacterial diversity, deficiencies in specific OTUs, and delayed microbial maturation. Results support dysbiosis in IgE-FA pathogenesis.

Proper Immune Response Depends on Early Exposure to Gut Microbiota in Broiler Chicks

The successional changes in the early intestinal microbiota occur concomitantly with the development, expansion, and education of the mucosal immune system. Although great attention of researchers has been focused on understanding the linkage between microbiota and immune functions, many essential details of the symbiotic relationship between the intestinal pioneer microbiota and the avian immune system remain to be discovered. This study was conducted to understand the impact of different early life intestinal colonizers on innate and adaptive immune processes in chicks and further identify immune-associated proteins expressed in the intestinal tissue. To accomplish it, we performed an in ovo application of two apathogenic Enterobacteriaceae isolates and lactic acid bacteria (L) to determine their influences on the intestinal proteome profile of broilers at the day of hatch (DOH) and at 10 days old. The results indicated that there were predicted biological functions of L-treated chicks associated with the activation and balanced function of the innate and adaptive immune systems. At the same time, the Enterobacteriaceae-exposed birds presented dysregulated immunological mechanisms or downregulated processes related to immune development. Those findings suggested that a proper immune function was dependent on specific gut microbiota exposure, in which the prenatal probiotic application may have favored the fitting programming of immune functions in chicks.

The Role of Intestinal Microbiota in Atopic Dermatitis

The early intestinal microbiota plays an important role in immune regulation, and the unbalanced composition may increase the occurrence of allergic diseases, including atopic dermatitis. This review summarizes the latest studies in the occurrence and development of intestinal microflora and its relationship with atopic dermatitis. These results are conducive to understand the differences in the composition of intestinal microbiota between patients with atopic dermatitis and healthy people, and provide a potential intervention for prevention or treatment of atopic dermatitis.

Effect of diet composition, a probiotic and a symbiotic treatment on the ileal microbiota composition of one-week-old broiler chickens

A healthy microbiota present in the small intestine contributes significantly to small intestinal function, including digestion, nutrient absorption and health. The current study investigated the effects of a prebiotic, a probiotic and a symbiotic supplementation on ileal microbiota composition of broilers at 7 days of age. In a total of 574 male Ross 308 day-old chickens were divided into four groups using six replicate pens and 24 chickens per pen. A maise-soybean based control diet (C), a control diet supplemented with probiotics (Broilact; Br), a control diet supplemented with symbiotic (inulin, yeast, Bacillus subtilis; Sy) and a wheat based diet supplemented with wheat bran (W) were formulated. On day 7 of life, two chickens per pen were slaughtered and ileal chymus samples were collected. For microbiota analysis 16S rRNA (V3-V4 region) gene targeted Illumina MiSeq sequencing was used. Feeding all diets supplemented increased the diversity to varying degrees compared to the control (C) diet (p=0.006). As a conclusion, all supplementation substantially influenced ileal microbiota of broiler chickens at an early age. All these results could offer some information for the future study on the relationship between early intestinal microbiota and the compounds of the feed.

Distinct gut microbiota and metabolite profiles induced by delivery mode in healthy Chinese infants

Delivery mode is recognized as an important determinant of gut microbiota composition. Vaginally delivered infants were colonized by maternal vaginal and fecal microbiota, while those delivered by cesarean section were colonized by environmental microorganisms. To reveal differences induced by delivery mode, we determined fecal microbiota and fecal metabolome from 60 infants in Northeast China region. Bacterial gene sequence analysis showed that the feces of vaginally delivered infants had the highest abundance of Bifidobacterium, Lactobacillus, Bacteroides and Parabacteroides, while the feces of cesarean section delivered infants were more enriched in Klebsiella. LC-MS-based metabolomics data demonstrated that the feces of vaginally delivered infants were associated with high abundance of DL-norvaline and DL-citrulline, while the feces of cesarean section delivered infants were abundant in trans-vaccenic acid and cis-aconitic acid. Moreover, the feces of vaginally delivered infants was significantly in positive correlation with tryptophan metabolism and pyruvate metabolism, however, the feces of cesarean section delivered infants was positively correlated with ABC transporters. Collectively, our study demonstrated that gut microbiota and metabolite profiles were significantly different between vaginally delivered and cesarean section delivered infants, and provided the theoretical basis for restoring the intestinal environment of cesarean section infants birthed in the study region. SignificanceThe intestinal microbiota and metabolites play important roles in infant development. To validate whether delivery modes influence the gut environment, we performed a detailed analysis of the earliest microbial colonization of the infant gut using a combination of 16S rRNA gene amplicon sequencing and LC-MS-based metabolomics. We found that the gut microbiota and metabolite composition were significantly different between vaginally delivered infants and cesarean section delivered infants. Our findings establish a vital baseline for studies tracking the infant gut microbiota and metabolite development following different delivery modes, and their associated effects on infant health. This study provides preliminary evidence that the observed differences due to delivery modes highlight their importance in shaping the early intestinal microbiota and metabolites.

Bile acids drive the newborn\u2019s gut microbiota maturation

Following birth, the neonatal intestine is exposed to maternal and environmental bacteria that successively form a dense and highly dynamic intestinal microbiota. Whereas the effect of exogenous factors has been extensively investigated, endogenous, host-mediated mechanisms have remained largely unexplored. Concomitantly with microbial colonization, the liver undergoes functional transition from a hematopoietic organ to a central organ of metabolic regulation and immune surveillance. The aim of the present study was to analyze the influence of the developing hepatic function and liver metabolism on the early intestinal microbiota. Here, we report on the characterization of the colonization dynamics and liver metabolism in the murine gastrointestinal tract (n = 6–10 per age group) using metabolomic and microbial profiling in combination with multivariate analysis. We observed major age-dependent microbial and metabolic changes and identified bile acids as potent drivers of the early intestinal microbiota maturation. Consistently, oral administration of tauro-cholic acid or β-tauro-murocholic acid to newborn mice (n = 7–14 per group) accelerated postnatal microbiota maturation.

A Proteomic View of the Cross-Talk Between Early Intestinal Microbiota and Poultry Immune System.

Proteomics has been used to investigate cross-talk between the intestinal microbiome and host biological processes. In this study, an in ovo technique and a proteomics approach was used to address how early bacterial colonization in the gastrointestinal tract (GIT) could modulate inflammatory and immune responses in young broilers. Embryos at 18 embryogenic days were inoculated with saline (S), 102 CFU of Citrobacter freundii (CF), Citrobacter species (C2), or lactic acid bacteria mixture (L) into the amnion. At 10 days posthatch, ileum samples from 12 birds per treatment were selected for tandem mass spectrometry analysis. Our further findings indicated that treatment-specific influences on early GIT microbiota resulted in different immune responses in mature broilers. Predicted functional analyses revealed activation of inflammation pathways in broilers treated in ovo with L and CF. Exposure to L enhanced functional annotation related to activation, trafficking of immune cells, and skeletal growth based-network, while CF inhibited biological functions associated with immune cell migration and inflammatory response. These results highlighted that proper immune function was dependent on specific GIT microbiota profiles, in which early-life exposure to L-based probiotic may have modulated the immune functions, whereas neonatal colonization of Enterobacteriaceae strains may have led to immune dysregulation associated with chronic inflammation.

Newcastle Disease Virus Infection Interferes With the Formation of Intestinal Microflora in Newly Hatched Specific-Pathogen-Free Chicks

Newcastle disease virus (NDV) infection leads to disproportion of intestinal tract microbiol population in chickens. Whether vertical infection of NDV affects the formation of a healthy and diverse intestinal community in newly hatched chicks, which might further perturb the establishment of a normal intestinal mucosal immunity, is unclear. This study examined the effects of NDV infection of chick embryos on the formation of the intestinal microbiome of chicks at hatch using 16S rRNA genes pyrosequencing. Eleven-day-old specific-pathogen-free chicken eggs were inoculated via intra-allantoic way with Class I NDV strain. At hatch, chicks were randomly selected and their duodenal and cecal contents were extracted and examined for the composition of gut microflora by Illumina sequencing of the V3+V4 region of the 16S rRNA genes. The results showed that the duodenal flora possesses a greater sample richness and higher microbial diversity as compared with the ceca flora in newly hatched chicks. In addition, there is a clear association with loss of important bacterial population in concert with an enrichment of potentially pathogenic population and NDV infections, both in the duodenum and ceca. It is also increasingly observed that the NDV infection may be associated with the dysbiosis of gut flora. This study presented a profile of the early intestinal microbiota in specific-pathogen-free chicks at hatch and strongly indicates that NDV infection interferes with the formation of intestinal microbiome in newly hatched chicks.

TERM INFANT FORMULA SUPPLEMENTED WITH HUMAN MILK OLIGOSACCHARIDES (2'FUCOSYLLACTOSE AND LACTO‐NEOTETRAOSE) SHIFTS STOOM MICROBIOTA AND METABOLIC SIGNATURES CLOSER TO THAT OF BREASTFED INFANTS.

Human milk oligosaccharides (HMOs) are thought to influence early intestinal microbiota establishment and may thereby provide benefits to formula‐fed infants. We evaluated the effect of infant formula with 2 HMOs (2'Fucosyllactose [2'FL] and Lacto‐N‐neotetraose [LNnT]) on the establishment of the intestinal microbiota in infants (ClinicalTrials.gov NCT01715246).Healthy term infants, who were 0–14 days old at enrolment, were randomized to intact protein cow's milk‐based infant formula (Control, n 87) or the same formula with 1.0 g/L 2'FL and 0.5 g/L LNnT (Test, n 88). Fully breastfed infants were also studied as a reference group (n 38). Stool samples were collected at 3 months of age for microbiota assessment using 16S rRNA gene sequencing and metagenomics; metabolic signature in stool was assessed using proton NMR.The global average microbial composition profile was established for infants from whom stool samples were available and who adhered to the protocol. A similar formula‐fed pattern for Control (n 65) and Test (n 58) was seen at the genus level, although Test appeared closer to breastfed (n 34) than Control. Calculation of microbial alpha diversity and comparison of the global microbiota composition using random permutations of the redundancy analysis (RDA) confirmed that Test was different from Control at genus level (p &lt; 0.001) and closer to the breastfed group. By statistical analyses we identified several taxa differentially present in Control and Test. These were Bifidobacterium (p = 0.01), Escherichia (p = 0.008), unclassified Coprobacillaceae (p = 0.01), unclassified Peptostreptococcaceae (p = 0.026), Dorea (p = 0.033), and Megamonas (p = 0.035). Correction for False Discovery Rate confirmed the first three taxa. Main discriminants between Test and Control by random forest analysis were Bifidobacterium, Escherichia and Peptostreptococcaceae. Clinically relevant pathogens were very rarely found; however, Clostridium difficile toxin A/B was detected in 14% of Test and 26% Control (OR 0.47, CI 0.17–1.27, p = 0.15). Multivariate stool metabolite analysis identified influential metabolites that discriminate between Test, Control and breastfed group. These were the amino acids phenylalanine, isoleucine, tyrosine, fecal organic acids and fucosylated compounds. Globally, the metabolic signatures observed in Test were more similar to those observed in stool of breastfed infants than Control. The observed profiles may indicate reduced protein fermentation in Test compared to Control.Together the stool microbiota and metabolic signature show that the addition of 2'FL and LNnT to a starter infant formula shift the stool microbiota towards that observed in breastfed infants, both in composition and function. Further studies are warranted to evaluate whether such a shift in gut ecology towards the breastfed standard leads to health benefits.

The Early Intestinal Microbiota of Healthy Korean Newborns.

Background:The microflora hypothesis may be the underlying explanation for the growth of inflammatory disease. In addition to many known affecting factors, knowing the gut microbiota of healthy newborns can help to understand the gut immunity and modulate it.Objectives:This study examined the microbiota of healthy newborns from urban regions.Patients and Methods:We enrolled 128 full-term newborns, born at Seoul St. Mary and St. Paul hospital from January 2009 to February 2010. All 143 samples of feces were cultivated in six culture plates to determine the amounts of total bacteria, anaerobes, gram-positive bacteria, coliforms, lactobacilli, and bifidobacteria. The samples were evaluated with a bivariate correlation between coliforms and lactobacilli. Terminal restriction fragment length polymorphism (T-RFLP) analysis with HhaI and MspI and a clustering analysis were performed for determination of diversity.Results:Bacteria were cultured in 61.5% of feces in the following order: anaerobes, gram-positive bacteria, lactobacilli, coliform, and bifidobacteria. The growth of total bacteria and lactobacilli increased in feces defecated after 24 hours of birth (P < 0.001, P = 0.008) and anaerobes decreased (P = 0.003). A negative correlation between the growth of lactobacilli and coliforms was found (r = -463, P < 0.001).Conclusions:This study confirms that bacterial colonization of healthy newborns born in cities is non-sterile, but has early diversification and inter-individuality.

The HLA-DQ2 genotype selects for early intestinal microbiota composition in infants at high risk of developing coeliac disease

ObjectiveIntestinal dysbiosis has been associated with coeliac disease (CD), but whether the alterations are cause or consequence of the disease is unknown. This study investigated whether the human leukocyte antigen...

Decreased gut microbiota diversity, delayed Bacteroidetes colonisation and reduced Th1 responses in infants delivered by Caesarean section

ObjectiveThe early intestinal microbiota exerts important stimuli for immune development, and a reduced microbial exposure as well as caesarean section (CS) has been associated with the development of allergic disease....

Diverse early intestinal microbiota as a key factor in necrotizing enterocolitis

Diverse early intestinal microbiota as a key factor in necrotizing enterocolitis

Probiotics for the prevention of allergic disease

Probiotics for the prevention of allergic disease

Diverse Early Intestinal Microbiota as a Contributing Factor in Necrotizing Enterocolitis

Diverse Early Intestinal Microbiota as a Contributing Factor in Necrotizing Enterocolitis