Integrated Role of Bifidobacterium animalis subsp. lactis Supplementation in Gut Microbiota, Immunity, and Metabolism of Infant Rhesus Monkeys

Impact of Formula Protein Quantity and Source on Infant Metabolism: Serum, Urine and Fecal Metabolomes of a Randomized Controlled Study

BACKGROUND

Human milk offers significant health benefits for infants; however, when not feasible, infant formula serves as an alternative. The higher protein content in infant formula is thought to contribute to the distinct metabolic profiles observed in formula-fed infants compared to those fed human milk.

OBJECTIVES

This study investigates the impact of formula protein quantity and whey protein types on the serum, urine, and fecal metabolomes of infants.

METHODS

A secondary analysis was performed on a random subset of 200 well-characterized per-protocol infants who completed a prospective, randomized, double-blind controlled trial. Infants were randomly assigned to one of three groups: standard formula, protein-reduced formula with α-lactalbumin-enriched whey, or protein-reduced formula with casein glycomacropeptide-reduced whey, along with an observational reference group of exclusively human milk-fed infants. Serum, urine, and fecal metabolites were quantified using 1H NMR spectroscopy at baseline (1-2 months), 4, and 6 months of age. Dietary intake was assessed monthly up to 6 months of age.

RESULTS

Formula protein content and type of whey protein used significantly influenced the amino acid profile and associated catabolic markers in serum and urine but had minimal impact on the fecal metabolome. Reduced protein formulas yielded metabolome profiles closer to those of human milk-fed infants compared to standard formula. Despite these improvements, infants fed human milk still demonstrated enhanced branched-chain amino acid (BCAA) oxidation and a greater capacity to eliminate catabolic waste products from BCAA metabolism over infants consuming protein-reduced formulas.

CONCLUSIONS

Comprehensive metabolomics profiling of serum, urine and feces captures molecular-level changes and informs potential strategies for formula optimization. Both the quantity and source of protein significantly influenced the metabolic profiles of formula-fed infants. However, modifications in protein alone cannot fully resolve the metabolic differences between formula-fed and human milk-fed infants, highlighting the complexity of mimicking the human milk feeding-associated metabolic profile.

CLINICAL TRIAL REGISTRATION

This study was registered at ClinicalTrials.gov as NCT02410057.

Gut microbiome: New perspectives for type 2 diabetes prevention and treatment

Type 2 diabetes mellitus (T2DM), which is distinguished by increased glucose levels in the bloodstream, is a metabolic disease with a rapidly increasing incidence worldwide. Nevertheless, the etiology and characteristics of the mechanism of T2DM remain unclear. Recently, abundant evidence has indicated that the intestinal microbiota is crucially involved in the initiation and progression of T2DM. The gut microbiome, the largest microecosystem, engages in material and energy metabolism in the human body. In this review, we concentrated on the correlation between the gut flora and T2DM. Meanwhile, we summarized the pathogenesis involving the intestinal flora in T2DM, as well as therapeutic approaches aimed at modulating the gut microbiota for the management of T2DM. Through the analysis presented here, we draw attention to further exploration of these research directions.

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.

Composition of the intestinal microbiota of infant rhesus macaques at different ages before and after weaning

Background

Rhesus macaques and humans are closely related genetically and share similar physiological and pathological characteristics. Exploring the impact of diet on the early establishment of gut microbiota in non-human primates can provide relevant clinical models for healthy infant growth and development. At present, few writers have focused on the composition and changes of the intestinal microbes of infant rhesus macaques throughout their progression from birth to formula feeding after weaning. In this study, we used 16S rRNA sequencing technology to explore the composition of the intestinal flora of rhesus macaques at different ages and analyzed the trends in the microbial changes.

Results

The results showed that the relative abundance of Bifidobacterium and Lactobacillus in the intestinal flora of infant rhesus macaques significantly decreased, and Prevotella increased with age. Bifidobacterium longum and Bifidobacterium breve are effective biomarkers to predict grouping. The metabolic pathways enriched in early life mainly concentrated in glycosphingolipid biosynthesis (lacto and neolacto series) and the degradation and metabolism of alcohols and esters.

Conclusions

We found that age was an important factor that affected the changes in the intestinal flora. This study revealed the change trend of flora in breastfed and formula-fed infant rhesus monkeys in different growth months, and found that the dominant flora changed greatly. This research provides a medically relevant theoretical basis for understanding the healthy development of infants.

Assessment of the role and mechanism of Bifidobacterium animalis subsp. lactis isolated from neonates' feces in protecting neonatal rats from Salmonella infection

OBJECTIVES

It is now well known that Bifidobacterium animalis subsp. lactis (B. lactis), an important early-life colonizer of the gut, provides immune-related benefits to infants. The aim of the work is to explore the intraspecific resistance to Salmonella infection of B. lactis isolated from neonatal feces, and to learn more insights into how B. lactis mediates beneficial roles in early-life infection resistance.

METHODS

Five strains of B. lactis (NFBAL11/NFBAL23/NFBAL44/NFBAL63/NFBAL92) were screened from fecal samples of neonates born within fifteen days and pretreated neonatal rats prior to infection with Salmonella typhimurium (S. typhimurium) SL1344. The survival rate, fecal occult blood, diarrhea and hepatosplenomegaly were detected to assess the ability of B. lactis to prevent S. typhimurium infection. Furthermore, the structure of mucus layer, gene expression, cytokine levels, antioxidant levels and intestinal microflora composition were detected to explore the mechanism.

RESULTS

All strains showed activity against S. typhimurium, with B. lactis NFBAL23 being the most active, followed by NFBAL63 and NFBAL92. And these advantages weren't attained by enhancing physical growth and development. Mechanistically, the neonatal rats treated with B. lactis (NFBAL23/NFBAL63/NFBAL92) had improved intestinal barrier function involving physical, chemical, immune and biological barriers in the face of challenges posed by S. typhimurium.

CONCLUSIONS

These findings revealed the intraspecific difference, beneficial roles and mechanisms of action of B. lactis against Salmonella infection early in life, which highlighted the necessity of supplementing appropriate B. lactis, and provided several potential B. lactis candidates for Salmonella infection treatment.

New Strategies for Enhancement of Infant Milk Formulas Composition

This article covers the issues of remodeling breast milk’s protective properties during creating infant milk formulas. First of all, this concerns the conditions for normal intestinal microbiota development in growing organism. Its quantitative and qualitative features are the trigger of either sanogenetic, or pathological immune and metabolic reactions, and also determine gut-brain axis functioning. The protective significance of prebiotic composition diversity of mammalian milk and the inductive role of breast milk oligosaccharides are shown. The modern concept of synbiotics role in gastrointestinal tract and other systems functioning, as well as the use of modern synbiotics in the creation of infant formulas (available Russian formula included) are presented.

Metabolic Phenotype and Microbiome of Infants Fed Formula Containing Lactobacillus paracasei Strain F-19

Early childhood nutrition drives the development of the gut microbiota. In contrast to breastfeeding, feeding infant formula has been shown to impact both the gut microbiota and the serum metabolome toward a more unfavorable state. It is thought that probiotics may alter the gut microbiota and hence create a more favorable metabolic outcome. To investigate the impact of supplementation with Lactobacillus paracasei spp. paracasei strain F-19 on the intestinal microbiota and the serum metabolome, infants were fed a formula containing L. paracasei F19 (F19) and compared to a cohort of infants fed the same standard formula without the probiotic (SF) and a breast-fed reference group (BF). The microbiome, as well as serum metabolome, were compared amongst groups. Consumption of L. paracasei F19 resulted in lower community diversity of the gut microbiome relative to the SF group that made it more similar to the BF group at the end of the intervention (4 months). It also significantly increased lactobacilli and tended to increase bifidobacteria, also making it more similar to the BF group. The dominant genus in the microbiome of all infants was Bifidobacterium throughout the intervention, which was maintained at 12 months. Although the serum metabolome of the F19 group was more similar to the group receiving the SF than the BF group, increases in serum TCA cycle intermediates and decreases in several amino acids in the metabolome of the F19 group were observed, which resulted in a metabolome that trended toward the BF group. Overall, L. paracasei F19 supplementation did not override the impact of formula-feeding but did impact the microbiome and the serum metabolome in a way that may mitigate some unfavorable metabolic impacts of formula-feeding.

Combined probiotics attenuate chronic unpredictable mild stress-induced depressive-like and anxiety-like behaviors in rats

Increasing evidence indicated that probiotics can be effective in improving behaviors similar to depression and anxiety disorders. However, the underlying mechanisms remain unclear, as is the effects of single vs. combined probiotics on depression and anxiety. This study aimed to determine whether combined probiotics could attenuate depressive-like and anxiety-like behavior induced by chronic unpredictable mild stress (CUMS) and its potential mechanisms. Rats underwent CUMS treatment and then administered Lactobacillus rhamnosus HN001 (HN001) or Bifidobacterium animalis subsp. lactis HN019 (HN019), alone or in combination. Levels of neurotransmitters, inflammatory factors, and the gut microbiota were measured. HN001 and (or) HN019 treatment improved depressive-like and anxiety-like behavior in rats, including increased moving distance and exploratory behavior (p < 0.05). In addition, altered gut microbiota structure induced by CUMS was amended by HN001 and/or HN019 (p < 0.05). HN001 and/or HN019 intervention also remarkably normalized levels of 5-HT, DA, NE, HVA, DOPAC, HIAA, TNF-α, IL-6, IL-18 and IL-1β in CUMS rats (p < 0.05). Furthermore, the effects of combined probiotics on decreasing inflammation and improved gut microbiota (Chao1 index and ACE index, p < 0.05) were superior to the single probiotics. Moreover, spearman analysis showed a certain correlation between the different microbiota, such as Firmicutes, Bacteroidetes, Verrucomicrobias, Proteobacterias and Actinobacterias, and inflammation and neurotransmitters. These findings suggested that CUMS induced depressive and anxiety-like behaviors can be alleviated by the combination of probiotics, which was possibly associated with the alterations in the gut microbiota composition and increased neurotransmitters and decreased inflammatory factors.

Neonatal Immune System Ontogeny: The Role of Maternal Microbiota and Associated Factors. How Might the Non-Human Primate Model Enlighten the Path?

Interactions between the immune system and the microbiome play a crucial role on the human health. These interactions start in the prenatal period and are critical for the maturation of the immune system in newborns and infants. Several factors influence the composition of the infant's microbiota and subsequently the development of the immune system. They include maternal infection, antibiotic treatment, environmental exposure, mode of delivery, breastfeeding, and food introduction. In this review, we focus on the ontogeny of the immune system and its association to microbial colonization from conception to food diversification. In this context, we give an overview of the mother-fetus interactions during pregnancy, the impact of the time of birth and the mode of delivery, the neonate gastrointestinal colonization and the role of breastfeeding, weaning, and food diversification. We further review the impact of the vaccination on the infant's microbiota and the reciprocal case. Finally, we discuss several potential therapeutic interventions that might help to improve the newborn and infant's health and their responses to vaccination. Throughout the review, we underline the main scientific questions that are left to be answered and how the non-human primate model could help enlighten the path.

A critical review of antibiotic resistance in probiotic bacteria

Probiotics are defined as live microorganisms that, when administered in adequate amounts, confer a health benefit upon the host. At present, probiotics are gaining popularity worldwide and are widely used in food and medicine. Consumption of probiotics is increasing with further in-depth research on the relationship between intestinal flora and host health. Most people pay more attention to the function of probiotics but ignore their potential risks, such as infection and antibiotic resistance transfer to pathogenic microbes. Physiological functions, effects and mechanisms of action of probiotics were covered in this review, as well as the antibiotic resistance phenotypes, mechanisms and genes found in probiotics. Typical cases of antibiotic resistance of probiotics were also highlighted, as well as the potential risks (including pathogenicity, infectivity and excessive immune response) and corresponding strategies (dosage, formulation, and administration route). This timely study provides an avenue for further research, development and application of probiotics.

Fecal microbiome and metabolome of infants fed bovine MFGM supplemented formula or standard formula with breast-fed infants as reference: a randomized controlled trial

Human milk delivers an array of bioactive components that safeguard infant growth and development and maintain healthy gut microbiota. Milk fat globule membrane (MFGM) is a biologically functional fraction of milk increasingly linked to beneficial outcomes in infants through protection from pathogens, modulation of the immune system and improved neurodevelopment. In the present study, we characterized the fecal microbiome and metabolome of infants fed a bovine MFGM supplemented experimental formula (EF) and compared to infants fed standard formula (SF) and a breast-fed reference group. The impact of MFGM on the fecal microbiome was moderate; however, the fecal metabolome of EF-fed infants showed a significant reduction of several metabolites including lactate, succinate, amino acids and their derivatives from that of infants fed SF. Introduction of weaning food with either human milk or infant formula reduces the distinct characteristics of breast-fed- or formula-fed- like infant fecal microbiome and metabolome profiles. Our findings support the hypothesis that higher levels of protein in infant formula and the lack of human milk oligosaccharides promote a shift toward amino acid fermentation in the gut. MFGM may play a role in shaping gut microbial activity and function.

Probiotic mechanisms of action

Intestinal dysbiosis is associated with a large number of disease processes including necrotizing enterocolitis and late-onset sepsis in preterm infants and colic and antibiotic-associated diarrhea in term infants. Probiotic microbes are increasingly administered to infants with the intent of decreasing risk of these acute diseases as well as chronic diseases of childhood such as asthma and atopic disease. The mechanisms by which probiotics decrease inflammation, decrease intestinal permeability, alter the intestinal microbiota, and influence metabolism have been discovered through both in vitro studies and in vivo in animal models. We review key mechanisms by which probiotic microbes improve health with emphasis on recent discoveries in the field.

Mixed Spices at Culinary Doses Have Prebiotic Effects in Healthy Adults: A Pilot Study

Spices were used as food preservatives prior to the advent of refrigeration, suggesting the possibility of effects on microbiota. Previous studies have shown prebiotic activities in animals and in vitro, but there has not been a demonstration of prebiotic or postbiotic effects at culinary doses in humans. In this randomized placebo-controlled study, we determined in twenty-nine healthy adults the effects on the gut microbiota of the consumption daily of capsules containing 5 g of mixed spices at culinary doses by comparison to a matched control group consuming a maltodextrin placebo capsule. The 16S ribosomal RNA sequencing data were used for microbial characterization. Spice consumption resulted in a significant reduction in Firmicutes abundance (p < 0.033) and a trend of enrichment in Bacteroidetes (p < 0.097) compared to placebo group. Twenty-six operational taxonomic units (OTUs) were different between the spice and placebo groups after intervention. Furthermore, there was a significant negative correlation between fecal short-chain fatty acid propionate concentration and Firmicutes abundance in spice intervention group (p < 0.04). The production of individual fecal short-chain fatty acid was not significantly changed by spice consumption in this study. Mixed spices consumption significantly modified gut microbiota, suggesting a prebiotic effect of spice consumption at culinary doses.

Methods to Assess the Antioxidative Properties of Probiotics

Probiotics prove useful in correcting and preventing numerous health conditions, including those having severe impact on society, e.g., obesity and cancer. Notably, these capabilities of probiotics appear to be associated with their antioxidant properties. The mechanisms of antioxidant action of probiotics range from immediate biochemical scavenging of reactive substances to induction of signaling events leading to increased capacity of the host's cytoprotective systems. Since the antioxidant effects of probiotics significantly vary in types and details, a broad selection of methods of assessment of these properties is required in order to identify, characterize, and develop novel probiotics for medical purposes, as well as to explain the mechanisms of action of probiotics already in use in healthcare. This review revises the versatile toolbox, which can be used to assess the antioxidant properties of probiotics.

Metabolic phenotype of breast-fed infants, and infants fed standard formula or bovine MFGM supplemented formula: a randomized controlled trial

Formula-fed (FF) infants exhibit a different metabolic profile than breast-fed (BF) infants. Two potential mechanisms are the higher protein level in formula compared with breast milk and the removal of the milk fat and associated milk fat globule membranes (MFGM) during production of infant formula. To determine whether MFGM may impact metabolism, formula-fed infants were randomly assigned to receive either an MFGM isolate-supplemented experimental formula (EF) or a standard formula (SF) from 2 until 6 months and compared with a BF reference group. Infants consuming EF had higher levels of fatty acid oxidation products compared to infants consuming SF. Although the protein level in the study formula was approximately 12 g/L (lower than most commercial formulas), a metabolic difference between FF and BF remained such that FF infants had higher levels of amino acid catabolism by-products and a low efficiency of amino acid clearance (preference for protein metabolism). BF infants had higher levels of fatty acid oxidation products (preference for fat metabolism). These unique, energy substrate-driven metabolic outcomes did not persist after diet was shifted to weaning foods and appeared to be disrupted by complementary feeding. Our results suggest that MFGM may have a role in directing infant metabolism.

Using probiotics for type 2 diabetes mellitus intervention: Advances, questions, and potential

Type 2 diabetes mellitus (T2DM) has become one of the most prevalent diseases on earth and several treatments have been developed. However, the current intervention approaches have not been as effective as expected. One promising supplementary strategy is the use of probiotics through direct or indirect approaches. Probiotics are microbial food cultures conferring health-promoting properties. In this review, we summarized the current theories and mechanisms of T2DM intervention using probiotics and hypothesize that probiotics intervene T2DM during its onsetting, developing, and complicating. For the first time, we comprehensively analyzed T2DM intervention in animal models using both wide-type probiotics in different forms and using recombinant probiotics. Then, probiotic intervention in T2DM patients was reviewed and the main results were compared with that obtained from animal studies. Finally yet importantly, remaining questions that are important such as in which form and in which state, as well as the future potential of probiotic intervention in T2DM were discussed from a perspective of food microbiologists. In conclusion, probiotic intervention in T2DM is promising but there are still many important issues unsolved yet. Critical review of the advances, questions, and potential of probiotic intervention in T2DM promotes the development of this approach for further application in humans.

The Fecal Metagenomics of Malayan Pangolins Identifies an Extensive Adaptation to Myrmecophagy

The characteristics of flora in the intestine of an animal, including the number and abundance of different microbial species and their functions, are closely related to the diets of the animal and affect the physical condition of the host. The Malayan pangolin (Manis javanica) is an endangered species that specializes in myrmecophagy. Analyzing the microbiome in the intestine of the pangolin is imperative to protect this species. By sequencing the metagenomes of the feces of four pangolins, we constructed a non-redundant catalog of 211,868 genes representing 1,811 metagenomic species. Taxonomic annotation revealed that Bacteroidetes (49.9%), Proteobacteria (32.2%), and Firmicutes (12.6%) are the three main phyla. The annotation of gene functions identified 5,044 genes from 88 different glycoside hydrolase (GH) families in the Carbohydrate-Active enZYmes database and 114 gene modules related to chitin-degrading enzymes, corresponding to the catalytic domains of GH18 family enzymes, containing chitinase genes of classes III and V in the dataset. Fourteen gene modules corresponded to the catalytic domains of GH19 family enzymes, containing chitinase genes of classes I, II, and IV. These genes were found in 37 species belonging to four phyla: Bacteroidetes, Cyanobacteria, Firmicutes, and Proteobacteria. Moreover, when the metabolic pathways of these genes were summarized, 41,711 genes were associated with 147 unique KEGG metabolic pathways, and these genes were assigned to two Gene Ontology terms: metabolic process and catalytic activity. We also found several species that likely play roles in the digestion of cellulose and may be able to degrade chitin, including Enterobacter cloacae, Lactococcus lactis, Chitinimonas koreensis, and Chitinophaga pinensis. In addition, we identified some intestinal microflora and genes related to diseases in pangolins. Twenty-seven species were identified by STAMP analysis as differentially abundant in healthy and diseased animals: 20 species, including Cellulosilyticum lentocellum and Lactobacillus reuteri, were more abundant in healthy pangolins, while seven species, including Odoribacter splanchnicus, Marinilabilia salmonicolor, Xanthomonas citri, Xanthomonas vasicola, Oxalobacter formigenes, Prolixibacter bellariivorans, and Clostridium bolteae, were more abundant in diseased pangolins. These results will support the efforts to conserve pangolins.

Establishment of a Macaca fascicularis gut microbiome gene catalog and comparison with the human, pig, and mouse gut microbiomes

Macaca fascicularis, the cynomolgus macaque, is a widely used model in biomedical research and drug development as its genetics and physiology are close to those of humans. Detailed information on the cynomolgus macaque gut microbiota, the functional interplay between the gut microbiota and host physiology, and possible similarities to humans and other mammalians is very limited. The aim of this study was to construct the first cynomolgus macaque gut microbial gene catalog and compare this catalog to the human, pig, and mouse gut microbial gene catalogs. We performed metagenomic sequencing on fecal samples from 20 cynomolgus macaques and identified 1.9 million non-redundant bacterial genes of which 39.49% and 25.45% are present in the human and pig gut bacterial gene catalogs, respectively, whereas only 0.6% of the genes are present in the mouse gut bacterial gene catalog. By contrast, at the functional levels, more than 76% Kyoto Encyclopedia of Genes and Genomes orthologies are shared between the gut microbiota of all four mammalians. Thirty-two highly abundant bacterial genera could be defined as core genera of these mammalians. We demonstrated significant differences in the composition and functional potential of the gut microbiota as well as in the distribution of predicted bacterial phage sequences in cynomolgus macaques fed either a low-fat/high-fiber diet or a high-fat/low-fiber diet. Interestingly, the gut microbiota of cynomolgus macaques fed the high-fat/low-fiber diet became more similar to the gut microbiota of humans.

Association between the gut microbiota and mineral metabolism

The aim of this review is to present the most recent scientific evidence of interactions between the intestinal microbiota and minerals, and the effect of this interaction on the health of the host. The Web of Science database from the years 2013-2017 on this topic was reviewed. Numerous in vitro studies have shown that iron significantly affects the intestinal microbiota. However, Bifidobacteriaceae are capable of binding iron in the large intestine, thereby limiting the formation of free radicals synthesized in the presence of iron, and thus reducing the risk of colorectal cancer. Animal studies have revealed that supplementation with probiotics, prebiotics and synbiotics has a significant effect on bone calcium, phosphate and bone metabolism. The dynamic interaction between microbiota and zinc was shown. Human studies have provided evidence of the influence of probiotic bacteria on parathormone, calcium and phosphate levels and thus on bone resorption. Recent studies have produced new information mainly on the impact of the intestinal bacteria on the metabolism of calcium and iron. From a scientific perspective, the most urgent fields that remain to be investigated are the identification of all human gut microbes and new therapies targeting the interaction between intestinal bacteria and minerals. © 2017 Society of Chemical Industry.