Early Effect of Supplemented Infant Formulae on Intestinal Biomarkers and Microbiota: A Randomized Clinical Trial

Unlocking the power of Lactoferrin: Exploring its role in early life and its preventive potential for adult chronic diseases

Nutrition during the early postnatal period exerts a profound impact on both infant development and later-life health. Breast milk, which contains lactoferrin, a dynamic protein, plays a crucial role in the growth of various biological systems and in preventing numerous chronic diseases. Based on the relationship between early infant development and chronic diseases later in life, this paper presents a review of the effects of lactoferrin in early life on neonates intestinal tract, immune system, nervous system, adipocyte development, and early intestinal microflora establishment, as well as the preventive and potential mechanisms of early postnatal lactoferrin against adult allergy, inflammatory bowel disease, depression, cancer, and obesity. Furthermore, we summarized the application status of lactoferrin in the early postnatal period and suggested directions for future research.

Two human milk-like synthetic bacterial communities displayed contrasted impacts on barrier and immune responses in an intestinal quadricellular model

The human milk (HM) microbiota, a highly diverse microbial ecosystem, is thought to contribute to the health benefits associated with breast-feeding, notably through its impact on infant gut microbiota. Our objective was to further explore the role of HM bacteria on gut homeostasis through a "disassembly/reassembly" strategy. HM strains covering the diversity of HM cultivable microbiota were first characterized individually and then assembled in synthetic bacterial communities (SynComs) using two human cellular models, peripheral blood mononuclear cells and a quadricellular model mimicking intestinal epithelium. Selected HM bacteria displayed a large range of immunomodulatory properties and had variable effects on epithelial barrier, allowing their classification in functional groups. This multispecies characterization of HM bacteria showed no clear association between taxonomy and HM bacteria impacts on epithelial immune and barrier functions, revealing the entirety and complexity of HM bacteria potential. More importantly, the assembly of HM strains into two SynComs of similar taxonomic composition but with strains exhibiting distinct individual properties, resulted in contrasting impacts on the epithelium. These impacts of SynComs partially diverged from the predicted ones based on individual bacteria. Overall, our results indicate that the functional properties of the HM bacterial community rather than the taxonomic composition itself could play a crucial role in intestinal homeostasis of infants.

Milk-derived small extracellular vesicles: a new perspective on dairy nutrition

Milk contains bioactive compounds that have multiple essential benefits. Milk-derived small extracellular vesicles (M-sEVs) have emerged as novel bioactive milk components with various beneficial biological functions and broad applications. The M-sEVs from different mammalian sources have similar composition and bioactive functions. The digestive stability and biocompatibility of the M-sEVs provide a good foundation for their physiological functions. Evidence suggests that M-sEVs promote intestinal, immune, bone, neural, liver, and heart health and show therapeutic effects against cancer, indicating their potential for use in functional foods. In addition, M-sEVs can be developed as natural delivery carriers owing to their superior structural characteristics. Further studies are needed to elucidate the relationship between the specific components and functions of M-sEVs, standardize their extraction processes, and refine relevant clinical trials to advance the future applications of M-sEVs. This review summarizes the structure and composition of M-sEVs isolated from different milk sources and discusses several common extraction methods. Since the introduction of M-sEVs for digestion and absorption, studies have been conducted on their biological functions. Furthermore, we outline the theoretical industrial production route, potential application scenarios of M-sEVs, and the future perspectives of M-sEV research.

Infant Feeding, Gut Permeability, and Gut Inflammation Markers

OBJECTIVES

Increased gut permeability and gut inflammation have been linked to the development of type 1 diabetes. Little is known on whether and how intake of different foods is linked to these mechanisms in infancy. We investigated whether the amount of breast milk and intake of other foods are associated with gut inflammation marker concentrations and permeability.

METHODS

Seventy-three infants were followed from birth to 12 months of age. Their diet was assessed with structured questionnaires and 3-day weighed food records at the age of 3, 6, 9, and 12 months. Gut permeability was assessed with the lactulose/mannitol test and fecal calprotectin and human β-defensin-2 (HBD-2) concentrations were analyzed from stool samples at the age of 3, 6, 9, and 12 months. The associations between foods and gut inflammation marker concentrations and permeability were analyzed using generalized estimating equations.

RESULTS

Gut permeability and gut inflammation marker concentrations decreased during the first year of life. Intake of hydrolyzed infant formula ( P = 0.003) and intake of fruits and juices ( P = 0.001) were associated with lower intestinal permeability. Intake of fruits and juices ( P < 0.001), vegetables ( P < 0.001), and oats ( P = 0.003) were associated with lower concentrations of HBD-2. Higher intake of breast milk was associated with higher fecal calprotectin concentrations ( P < 0.001), while intake of fruits and juices ( P < 0.001), vegetables ( P < 0.001), and potatoes ( P = 0.007) were associated with lower calprotectin concentrations.

CONCLUSIONS

Higher intake of breast milk may contribute to higher calprotectin concentration, whereas several complementary foods may decrease gut permeability and concentrations of calprotectin and HBD-2 in infant gut.

Effect of Lacticaseibacillus paracasei N1115 on Immunomodulatory and Gut Microbial Composition in Young Children: A Randomized, Placebo-Controlled Study

Lactobacillus paracasei N1115 (Lp N1115) was isolated from fermented milk products. The administration of Lp N1115 is safe and well tolerated in Chinese children, but its effectiveness among young Chinese children is still unclear. To investigate the efficacy of Lp N1115 as a probiotic to enhance gut development in Chinese infants and toddlers born by cesarean section, 109 healthy and cesarean-delivered infants aged 6-24 months were recruited for a 12-week randomized, placebo-controlled trial, with 101 finally completing the study. Saliva and stool samples were collected and detected at weeks 0, 4, 8, and 12 of the intervention. Statistical analyses were performed by using a per-protocol (PP) approach. After 12 weeks of intervention, the fecal pH in the control group increased (p = 0.003), while the fecal pH in the experimental group did not change. Salivary cortisol decreased from baseline in the experimental group (p = 0.023), while the control group showed little change. In addition, Lp N1115 increased the fecal sIgA content of infants aged 6-12 months (p = 0.044) but had no obvious effect on fecal calprotectin and saliva sIgA. At week 4, the increase in Lactobacillus relative to baseline was higher in the experimental group than in the control group (p = 0.019). Further analysis showed a trend toward a higher detection rate of Lactobacillus in the experimental group than in the control group (p = 0.039). In conclusion, Lp N1115 was able to enhance the content of Lactobacillus and maintain fecal pH levels. Its beneficial effects on gut development were more obvious in 6-12-month-old infants.

Pre-, pro-, syn-, and Postbiotics in Infant Formulas: What Are the Immune Benefits for Infants?

The first objective of infant formulas is to ensure the healthy growth of neonates and infants, as the sole complete food source during the first months of life when a child cannot be breastfed. Beyond this nutritional aspect, infant nutrition companies also try to mimic breast milk in its unique immuno-modulating properties. Numerous studies have demonstrated that the intestinal microbiota under the influence of diet shapes the maturation of the immune system and influences the risk of atopic diseases in infants. A new challenge for dairy industries is, therefore, to develop infant formulas inducing the maturation of immunity and the microbiota that can be observed in breastfed delivered vaginally, representing reference infants. Streptococcus thermophilus, Lactobacillus reuteri DSM 17938, Bifidobacterium breve (BC50), Bifidobacterium lactis Bb12, Lactobacillus fermentum (CECT5716), and Lactobacillus rhamnosus GG (LGG) are some of the probiotics added to infant formula, according to a literature review of the past 10 years. The most frequently used prebiotics in published clinical trials are fructo-oligosaccharides (FOSs), galacto-oligosaccharides (GOSs), and human milk oligosaccharides (HMOs). This review sums up the expected benefits and effects for infants of pre-, pro-, syn-, and postbiotics added to infant formula regarding the microbiota, immunity, and allergies.

The application of lactoferrin in infant formula: The past, present and future

Human milk is universally regarded as the gold standard to fulfill nutrition needs of infants. Lactoferrin (LF) is a major multiple bioactive glycoprotein in human milk but little is presented in infant formula. LF can resist digestion in the infant gastrointestinal tract and is absorbed into the bloodstream in an intact form to perform physiological functions. Evidence suggest that LF prevents pathogen infection, promotes immune system development, intestinal development, brain development and bone health, as well as ameliorates iron deficiency anemia. However, more clinical studies of LF need to be further elucidated to determine an appropriate dosage for application in infant formula. LF is sensitive to denaturation induced by processing of infant formula such as heat treatments and spay drying. Thus, further studies should be focus on maximizing the retention of LF activity in the infant formula process. This review summarizes the structural features of LF. Then the digestion, absorption and metabolism of LF in infants are discussed, followed by the function of LF for infants. Further, we summarize LF in infant formula and effects of processing of infant formula on bioactivities of LF, as well as future perspectives of LF research.

Infant feeding practice and gastrointestinal tolerance: a real-world, multi-country, cross-sectional observational study

BACKGROUND

Signs of feeding intolerance, such as gastrointestinal (GI) symptoms, are frequently observed in otherwise healthy formula-fed infants in the first months of life. The primary objective of this observational study was to examine GI tolerance in formula-fed infants (FFI) vs. breastfed infants (BFI) in a real-world setting with a secondary objective being the comparison of infants fed formula with pre- and/or probiotics (FFI_PP) and those fed formula without any pre- and/or probiotics (FFI_noPP) as well as BFI.

METHODS

A six-country, cross-sectional study in full-term exclusively/predominantly FFI (n = 2036) and BFI (n = 760) aged 6-16 weeks was conducted using the validated Infant Gastrointestinal Symptom Questionnaire (IGSQ) and a Feeding Practice and Gut Comfort Questionnaire.

RESULTS

The IGSQ composite score in FFI was non-inferior compared to BFI (mean difference [95%CI]: 0.17 [-0.34, 0.67]; non-inferiority p-value < 0.0001) and scores for BFI and FFI were below the threshold of 23, indicating no GI discomfort. Adjusted mean IGSQ scores ± SE were similar in FFI_PP (22.1 ± 0.2) and BFI (22.3 ± 0.3) while FFI_noPP (23.4 ± 0.3) was significantly higher and above 23 indicating some GI discomfort (mean differences [95%CI] FFI_noPP minus FFI_PP and FFI_noPP minus BFI were 1.28 [0.57, 1.98] and 1.09 [0.38, 1.80], respectively; both p < 0.01). Hard stools and difficulty in passing stool were more common in FFI compared to BFI (p < 0.01) but were less common in FFI_PP compared to FFI_noPP (p < 0.01). FFI_PP showed significantly less crying than FFI_noPP and was similar to BFI. Significantly fewer physician-confirmed colic episodes (Rome IV criteria) were reported in FFI_PP compared with FFI_noPP or BFI.

CONCLUSIONS

In this real-world observational study, FFI had non-inferior overall GI tolerance compared to BFI. Within FFI, infants receiving formulas with pre- and/or probiotics had a better GI tolerance, improved stooling and less infantile colic compared to those receiving formula without any pre- and/or probiotics and were more similar to BFI.

TRIAL REGISTRATION

NCT03703583, 12/10/2018 ( https://clinicaltrials.gov/ct2/show/NCT03703583 ).

Infant nutrition affects the microbiota-gut-brain axis: Comparison of human milk vs. infant formula feeding in the piglet model

Early nutrition plays a dominant role in infant development and health. It is now understood that the infant diet impacts the gut microbiota and its relationship with gut function and brain development. However, its impact on the microbiota-gut-brain axis has not been studied in an integrative way. The objective here was to evaluate the effects of human milk (HM) or cow’s milk based infant formula (IF) on the relationships between gut microbiota and the collective host intestinal-brain axis. Eighteen 10-day-old Yucatan mini-piglets were fed with HM or IF. Intestinal and fecal microbiota composition, intestinal phenotypic parameters, and the expression of genes involved in several gut and brain functions were determined. Unidimensional analyses were performed, followed by multifactorial analyses to evaluate the relationships among all the variables across the microbiota-gut-brain axis. Compared to IF, HM decreased the α-diversity of colonic and fecal microbiota and modified their composition. Piglets fed HM had a significantly higher ileal and colonic paracellular permeability assessed by ex vivo analysis, a lower expression of genes encoding tight junction proteins, and a higher expression of genes encoding pro-inflammatory and anti-inflammatory immune activity. In addition, the expression of genes involved in endocrine function, tryptophan metabolism and nutrient transport was modified mostly in the colon. These diet-induced intestinal modifications were associated with changes in the brain tissue expression of genes encoding the blood-brain barrier, endocrine function and short chain fatty acid receptors, mostly in hypothalamic and striatal areas. The integrative approach underlined specific groups of bacteria (Veillonellaceae, Enterobacteriaceae, Lachnospiraceae, Rikenellaceae, and Prevotellaceae) associated with changes in the gut-brain axis. There is a clear influence of the infant diet, even over a short dietary intervention period, on establishment of the microbiota-gut-brain axis.

Exploring the Potential of Human Milk and Formula Milk on Infants’ Gut and Health

Early-life gut microbiota plays a role in determining the health and risk of developing diseases in later life. Various perinatal factors have been shown to contribute to the development and establishment of infant gut microbiota. One of the important factors influencing the infant gut microbial colonization and composition is the mode of infant feeding. While infant formula milk has been designed to resemble human milk as much as possible, the gut microbiome of infants who receive formula milk differs from that of infants who are fed human milk. A diverse microbial population in human milk and the microbes seed the infant gut microbiome. Human milk contains nutritional components that promote infant growth and bioactive components, such as human milk oligosaccharides, lactoferrin, and immunoglobulins, which contribute to immunological development. In an attempt to encourage the formation of a healthy gut microbiome comparable to that of a breastfed infant, manufacturers often supplement infant formula with prebiotics or probiotics, which are known to have a bifidogenic effect and can modulate the immune system. This review aims to elucidate the roles of human milk and formula milk on infants’ gut and health.

The gut microbiota - a vehicle for the prevention and treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) arises principally against a background of cirrhosis and these two diseases are responsible globally for over 2 million deaths a year. There are few treatment options for liver cirrhosis and HCC, so it is vital to arrest these pathologies early in their development. To do so, we propose dietary and therapeutic solutions that involve the gut microbiota and its consequences. Integrated dietary, environmental and intrinsic signals result in a bidirectional connection between the liver and the gut with its microbiota, known as the gut-liver axis. Numerous lifestyle factors can result in dysbiosis with a change in the functional composition and metabolic activity of the microbiota. A panoply of metabolites can be produced by the microbiota, including ethanol, secondary bile acids, trimethylamine, indole, quinolone, phenazine and their derivatives and the quorum sensor acyl homoserine lactones that may contribute to HCC but have yet to be fully investigated. Gram-negative bacteria can activate the pattern recognition receptor toll-like receptor 4 (TLR4) in the liver leading to nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling, which can contribute to HCC initiation and progression. The goal in preventing HCC should be to ensure a healthy gut microbiota using probiotic supplements containing beneficial bacteria and prebiotic plant fibers such as oligosaccharides that stimulate their growth. The clinical development of TLR4 antagonists is urgently needed to counteract the pathological effects of dysbiosis on the liver and other organs. Further nutrigenomic studies are required to understand better how the diet influences the gut microbiota and its adverse effects on the liver.

Neonatal Programming of Microbiota Composition: A Plausible Idea That Is Not Supported by the Evidence

Underpinning the theory “developmental origins of health and disease” (DOHaD), evidence is accumulating to suggest that the risks of adult disease are in part programmed by exposure to environmental factors during the highly plastic “first 1,000 days of life” period. An elucidation of the mechanisms involved in this programming is challenging as it would help developing new strategies to promote adult health. The intestinal microbiome is proposed as a long-lasting memory of the neonatal environment. This proposal is supported by indisputable findings such as the concomitance of microbiota assembly and the first 1,000-day period, the influence of perinatal conditions on microbiota composition, and the impact of microbiota composition on host physiology, and is based on the widely held but unconfirmed view that the microbiota is long-lastingly shaped early in life. In this review, we examine the plausibility of the gut microbiota being programmed by the neonatal environment and evaluate the evidence for its validity. We highlight that the capacity of the pioneer bacteria to control the implantation of subsequent bacteria is supported by both theoretical principles and statistical associations, but remains to be demonstrated experimentally. In addition, our critical review of the literature on the long-term repercussions of selected neonatal modulations of the gut microbiota indicates that sustained programming of the microbiota composition by neonatal events is unlikely. This does not exclude the microbiota having a role in DOHaD due to a possible interaction with tissue and organ development during the critical windows of neonatal life.

Infant formula containing bovine milk-derived oligosaccharides supports age-appropriate growth and improves stooling pattern

BACKGROUND

Adding bovine milk-derived oligosaccharides (MOS) enhances the oligosaccharide profile of infant formula. This study aimed to evaluate the safety and efficacy of a MOS-supplemented infant formula.

METHODS

In this double-blind randomized controlled trial, healthy infants 21-26 days old were either assigned to bovine milk-based, alpha-lactalbumin, and sn-2 palmitate enriched infant formula (control, n = 115) or the same formula with 7.2 g MOS/L (test, n = 115) until aged 6 months. Co-primary endpoints were weight gain through 4 months and stool consistency (validated scale: 1 = watery to 5 = hard). Secondary endpoints included parent-reported GI tolerance, health-related quality of life (HRQoL), and adverse events (AEs).

RESULTS

Weight gain was similar (p = 0.695); the difference between test and control (mean; 95% CI: 0.29; -1.15, 1.73 g/day) was above the non-inferiority margin (-3 g/day). Test had softer stools than control (mean difference in stool consistency score: -0.31; 95% CI: -0.42, -0.21; P < 0.0001); fewer parental reports of harder stools (OR = 0.32, 95% CI: 0.20, 0.49; P < 0.0001) and less difficulties in passing stool (OR = 0.25, 95% CI: 0.09, 0.65; P = 0.005). Parent-reported GI tolerance and HRQoL were similar between groups as were the overall low AEs.

CONCLUSIONS

MOS-supplemented infant formula is safe and well-tolerated while supporting normal infant growth and promotes softer stooling pattern without increasing parent-reported and physician-confirmed adverse health concerns.

IMPACT

This is the first study investigating the addition of bovine milk-derived oligosaccharides to an infant formula enriched with alpha-lactalbumin and elevated levels of sn-2 palmitate, providing safety and efficacy data for such a formula. Term infant formula supplemented with 7.2 g bovine milk-derived oligosaccharides per liter supported normal infant growth, was well-tolerated and safe. Addition of bovine milk-derived oligosaccharides to term infant formula promoted softer stooling pattern and reduced difficulties in passing stool. The study shows that bovine milk-derived oligosaccharide supplemented infant formula is a safe and effective option for healthy term infants who are formula-fed.

Term Infant Formulas Influencing Gut Microbiota: An Overview

Intestinal colonization of the neonate is highly dependent on the term of pregnancy, the mode of delivery, the type of feeding [breast feeding or formula feeding]. Postnatal immune maturation is dependent on the intestinal microbiome implementation and composition and type of feeding is a key issue in the human gut development, the diversity of microbiome, and the intestinal function. It is well established that exclusive breastfeeding for 6 months or more has several benefits with respect to formula feeding. The composition of the new generation of infant formulas aims in mimicking HM by reproducing its beneficial effects on intestinal microbiome and on the gut associated immune system (GAIS). Several approaches have been developed currently for designing new infant formulas by the addition of bioactive ingredients such as human milk oligosaccharides (HMOs), probiotics, prebiotics [fructo-oligosaccharides (FOSs) and galacto-oligosaccharides (GOSs)], or by obtaining the so-called post-biotics also known as milk fermentation products. The aim of this article is to guide the practitioner in the understanding of these different types of Microbiota Influencing Formulas by listing and summarizing the main concepts and characteristics of these different models of enriched IFs with bioactive ingredients.

Term infant formula supplemented with milk-derived oligosaccharides shifts the gut microbiota closer to that of human milk-fed infants and improves intestinal immune defense: a randomized controlled trial

BACKGROUND

Bovine milk-derived oligosaccharides (MOS) containing primarily galacto-oligosaccharides with inherent concentrations of sialylated oligosaccharides can be added to infant formula to enhance the oligosaccharide profile.

OBJECTIVE

To investigate the effects of an MOS-supplemented infant formula on gut microbiota and intestinal immunity.

METHODS

In a double-blind, randomized, controlled trial, healthy term formula-fed infants aged 21-26 d either received an intact protein cow milk-based formula (control group, CG, n = 112) or the same formula containing 7.2 g MOS/L (experimental group, EG, n = 114) until the age of 6 mo. Exclusively human milk-fed infants (HFI, n = 70) from an observational study served as the reference. Fecal samples collected at baseline, and the ages of 2.5 and 4 mo were assessed for microbiota (16S ribosomal RNA-based approaches), metabolites, and biomarkers of gut health and immune response.

RESULTS

Aged 2.5 and 4 mo, redundancy analysis (P = 0.002) and average phylogenetic distance (P < 0.05) showed that the overall microbiota composition in EG was different from CG and closer to that of HFI. Similarly, EG caesarean-born infants were different from CG caesarean- or vaginally born infants and approaching HFI vaginally born infants. Relative bifidobacteria abundance was higher in EG compared with CG (P < 0.05) approaching HFI. At the age of 4 mo, counts of Clostridioides difficile and Clostridium perfringens were ∼90% (P < 0.001) and ∼65% (P < 0.01) lower in EG compared with CG, respectively. Geometric LS mean (95% CI) fecal secretory IgA in EG was twice that of CG [70 (57, 85) compared with 34 (28, 42) mg/g, P < 0.001] and closer to HFI. Fecal oral polio vaccine-specific IgA was ∼50% higher in EG compared with CG (P = 0.065). Compared with CG, EG and HFI had lower fecal calcium excretion (by ∼30%, P < 0.005) and fecal pH (P < 0.001), and higher lactate concentration (P < 0.001).

CONCLUSIONS

Infant formula with MOS shifts the gut microbiota and metabolic signature closer to that of HFI, has a strong bifidogenic effect, reduces fecal pathogens, and improves the intestinal immune response.

Nurturing the Early Life Gut Microbiome and Immune Maturation for Long Term Health

Early life is characterized by developmental milestones such as holding up the head, turning over, sitting up and walking that are typically achieved sequentially in specific time windows. Similarly, the early gut microbiome maturation can be characterized by specific temporal microorganism acquisition, colonization and selection with differential functional features over time. This orchestrated microbial sequence occurs from birth during the first years of age before the microbiome reaches an adult-like composition and function between 3 and 5 years of age. Increasingly, these different steps of microbiome development are recognized as crucial windows of opportunity for long term health, primarily linked to appropriate immune and metabolic development. For instance, microbiome disruptors such as preterm and Cesarean-section birth, malnutrition and antibiotic use are associated with increased risk to negatively affect long-term immune and metabolic health. Different age discriminant microbiome taxa and functionalities are used to describe age-appropriate microbiome development, and advanced modelling techniques enable an understanding and visualization of an optimal microbiome maturation trajectory. Specific microbiome features can be related to later health conditions, however, whether such features have a causal relationship is the topic of intense research. Early life nutrition is an important microbiome modulator, and 'Mother Nature' provides the model with breast milk as the sole source of nutrition for the early postnatal period, while dietary choices during the prenatal and weaning period are to a large extent guided by tradition and culture. Increasing evidence suggests prenatal maternal diet and infant and child nutrition impact the infant microbiome trajectory and immune competence development. The lack of a universal feeding reference for such phases represents a knowledge gap, but also a great opportunity to provide adequate nutritional guidance to maintain an age-appropriate microbiome for long term health. Here, we provide a narrative review and perspective on our current understanding of age-appropriate microbiome maturation, its relation to long term health and how nutrition shapes and influences this relationship.

The critical roles of iron during the journey from fetus to adolescent: Developmental aspects of iron homeostasis

Iron is indispensable for human life. However, it is also potentially toxic, since it catalyzes the formation of harmful oxidative radicals in unbound form and may facilitate pathogen growth. Therefore, iron homeostasis needs to be tightly regulated. Rapid growth and development require large amounts of iron, while (especially young) children are vulnerable to infections with iron-dependent pathogens due to an immature immune system. Moreover, unbalanced iron status early in life may have effects on the nervous system, immune system and gut microbiota that persist into adulthood. In this narrative review, we assess the critical roles of iron for growth and development and elaborate how the body adapts to physiologically high iron demands during the journey from fetus to adolescent. As a first step towards the development of clinical guidelines for the management of iron disorders in children, we summarize the unmet needs regarding the developmental aspects of iron homeostasis.

The gut microbiota is associated with the small intestinal paracellular permeability and the development of the immune system in healthy children during the first two years of life

BACKGROUND

The intestinal barrier plays an important role in the defense against infections, and nutritional, endocrine, and immune functions. The gut microbiota playing an important role in development of the gastrointestinal tract can impact intestinal permeability and immunity during early life, but data concerning this problem are scarce.

METHODS

We analyzed the microbiota in fecal samples (101 samples in total) collected longitudinally over 24 months from 21 newborns to investigate whether the markers of small intestinal paracellular permeability (zonulin) and immune system development (calprotectin) are linked to the gut microbiota. The results were validated using data from an independent cohort that included the calprotectin and gut microbiota in children during the first year of life.

RESULTS

Zonulin levels tended to increase for up to 6 months after childbirth and stabilize thereafter remaining at a high level while calprotectin concentration was high after childbirth and began to decline from 6 months of life. The gut microbiota composition and the related metabolic potentials changed during the first 2 years of life and were correlated with zonulin and calprotectin levels. Faecal calprotectin correlated inversely with alpha diversity (Shannon index, r = - 0.30, FDR P (Q) = 0.039). It also correlated with seven taxa; i.a. negatively with Ruminococcaceae (r = - 0.34, Q = 0.046), and Clostridiales (r = - 0.34, Q = 0.048) and positively with Staphylococcus (r = 0.38, Q = 0.023) and Staphylococcaceae (r = 0.35, Q = 0.04), whereas zonulin correlated with 19 taxa; i.a. with Bacillales (r = - 0.52, Q = 0.0004), Clostridiales (r = 0.48, Q = 0.001) and the Ruminococcus (torques group) (r = 0.40, Q = 0.026). When time intervals were considered only changes in abundance of the Ruminococcus (torques group) were associated with changes in calprotectin (β = 2.94, SE = 0.8, Q = 0.015). The dynamics of stool calprotectin was negatively associated with changes in two MetaCyc pathways: pyruvate fermentation to butanoate (β = - 4.54, SE = 1.08, Q = 0.028) and Clostridium acetobutylicum fermentation (β = - 4.48, SE = 1.16, Q = 0.026).

CONCLUSIONS

The small intestinal paracellular permeability, immune system-related markers and gut microbiota change dynamically during the first 2 years of life. The Ruminococcus (torques group) seems to be especially involved in controlling paracellular permeability. Staphylococcus, Staphylococcaceae, Ruminococcaceae, and Clostridiales, may be potential biomarkers of the immune system. Despite observed correlations their clear causation and health consequences were not proven. Mechanistic studies are required.

Bovine Milk Oligosaccharides and Human Milk Oligosaccharides Modulate the Gut Microbiota Composition and Volatile Fatty Acid Concentrations in a Preclinical Neonatal Model

Milk oligosaccharides (OS) shape microbiome structure and function, but their relative abundances differ between species. Herein, the impact of the human milk oligosaccharides (HMO) (2′-fucosyllactose [2′FL] and lacto-N-neotetraose [LNnT]) and OS isolated from bovine milk (BMOS) on microbiota composition and volatile fatty acid (VFA) concentrations in ascending colon (AC) contents and feces was assessed. Intact male piglets received diets either containing 6.5 g/L BMOS (n = 12), 1.0 g/L 2′FL + 0.5 g/L LNnT (HMO; n = 12), both (HMO + BMOS; n = 10), or neither (CON; n = 10) from postnatal day (PND) 2 to 34. Microbiota were assessed by 16S rRNA gene sequencing and real-time PCR, and VFA were measured by gas chromatography. The microbiota was affected by OS in an intestine region-specific manner. BMOS reduced (p < 0.05) microbial richness in the AC, microbiota composition in the AC and feces, and acetate concentrations in AC, regardless of HMO presence. HMO alone did not affect overall microbial composition, but increased (p < 0.05) the relative proportion of specific taxa, including Blautia, compared to other groups. Bacteroides abundance was increased (p < 0.05) in the AC by BMOS and synergistically by BMOS + HMO in the feces. Distinct effects of HMO and BMOS suggest complementary and sometimes synergistic benefits of supplementing a complex mixture of OS to formula.

Host Factors of Favorable Intestinal Microbial Colonization

Gut microbial colonization starts with birth and initiates a complex process between the host and the microbiota. Successful co-development of both establishes a symbiotic mutual relationship and functional homeostasis, while alterations thereof predispose the individual life-long to inflammatory and metabolic diseases. Multiple data have been provided how colonizing microbes induce a reprogramming and maturation of immunity by providing crucial instructing information to the newborn immune system. Less is known about what host factors have influence on the interplay between intestinal immunity and the composition of the gut microbial ecology. Here we review existing evidence regarding host factors that contribute to a favorable development of the gut microbiome and thereby successful maturation of gut mucosal immunity.

Can phytotherapy with polyphenols serve as a powerful approach for the prevention and therapy tool of novel coronavirus disease 2019 (COVID-19)?

Much more serious than the previous severe acute respiratory syndrome (SARS) coronavirus (CoV) outbreaks, the novel SARS-CoV-2 infection has spread speedily, affecting 213 countries and causing ∼17,300,000 cases and ∼672,000 (∼+1,500/day) deaths globally (as of July 31, 2020). The potentially fatal coronavirus disease (COVID-19), caused by air droplets and airborne as the main transmission modes, clearly induces a spectrum of respiratory clinical manifestations, but it also affects the immune, gastrointestinal, hematological, nervous, and renal systems. The dramatic scale of disorders and complications arises from the inadequacy of current treatments and absence of a vaccine and specific anti-COVID-19 drugs to suppress viral replication, inflammation, and additional pathogenic conditions. This highlights the importance of understanding the SARS-CoV-2 mechanisms of actions and the urgent need of prospecting for new or alternative treatment options. The main objective of the present review is to discuss the challenging issue relative to the clinical utility of plants-derived polyphenols in fighting viral infections. Not only is the strong capacity of polyphenols highlighted in magnifying health benefits, but the underlying mechanisms are also stressed. Finally, emphasis is placed on the potential ability of polyphenols to combat SARS-CoV-2 infection via the regulation of its molecular targets of human cellular binding and replication, as well as through the resulting host inflammation, oxidative stress, and signaling pathways.