Exploring the potential of prebiotic and polyphenol-based dietary interventions for the alleviation of cognitive and gastrointestinal perturbations associated with military specific stressors

Active military personnel are often subject to extreme stressors, whether psychological or physical. Such stressors often result in soldiers having severe gastrointestinal diseases and cognitive perturbations such as Post Traumatic Stress Disorder (PTSD). Whilst pharmaceutical treatments are available, they are not always the most viable option, either because of poor efficacy, side effects, availability or economic detriment. By exploring the potential of beneficial nutritional interventions, it may be possible to establish whether the increased intake of certain nutraceuticals (such as polyphenols and prebiotics) could improve psychological and gut health in combat soldiers, and reduce the effects that PTSD and related gastrointestinal issues have on health and wellbeing. This report investigates the link between prebiotics, polyphenols and cognitive and gastrointestinal health

Inulin‐type fructans and short‐chain fructooligosaccharides—their role within the food industry as fat and sugar replacers and texture modifiers—what needs to be considered!

Inulin and oligofructose are classes of prebiotics belonging to a group of nondigestible carbohydrates referred to as inulin‐type fructans. While short‐chain fructooligosaccharides are enzymatically synthesized from the hydrolysis and transglycosylation of sucrose. Inulin‐type fructans and short‐chain fructooligosaccharides act as carbon sources for selective pathways supporting digestive health including altering the composition of the gut microbiota along with improving transit time. Due to their physicochemical properties, inulin‐type fructans and short‐chain fructooligosaccharides have been widely used in the food industry as partial replacements for both fat and sugar. Yet, levels of replacement need to be carefully considered as it may result in changes to physical and sensory properties that could be detected by consumers. Furthermore, it has been reported depending on the processing parameters used during production that inulin‐type fructans and short‐chain fructooligosaccharides may or may not undergo structural alterations. Therefore, this paper reviews the role of inulin‐type fructans and short‐chain fructooligosaccharides within the food industry as fat and sugar replacers and texture modifiers, their impact on final sensory properties, and to what degree processing parameters are likely to impact their functional properties

Oligofructose alone and in combination with 2'fucosyllactose induces physiologically relevant changes in γ-aminobutyric acid and organic acid production compared to sole 2'fucosyllactose supplementation: an in vitro study

We explored the potential for the prebiotic oligofructose and prebiotic candidate 2'fucosyllactose, alone and in combination (50:50 blend) to induce physiologically relevant increases in neurotransmitter (γ-aminobutyric acid, serotonin, tryptophan, and dopamine) and organic acid (acetate, propionate, butyrate, lactate, and succinate) production as well as microbiome changes using anaerobic pH-controlled in vitro batch culture fermentations over 48 h. Changes in organic acid and neurotransmitter production were assessed by gas chromatography and liquid chromatography and, bacterial enumeration using fluorescence in situ hybridization, respectively. Both oligofructose and oligofructose/2'fucosyllactose combination fermentations induced physiologically relevant concentrations of γ-aminobutyric acid, acetate, propionate, butyrate, and succinate at completion (all P ≤ .05). A high degree of heterogeneity was seen amongst donors in both neurotransmitter and organic acid production in sole 2'FL fermentations suggesting a large responder/nonresponder status exists. Large increases in Bifidobacterium, Lactobacillus, and Bacteroides numbers were detected in oligofructose fermentation, smallest increases being detected in 2'fucosyllactose fermentation. Bacterial numbers in the combined oligofructose/2'fucosyllactose fermentation were closer to that of sole oligofructose. Our results indicate that oligofructose and oligofructose/2'fucosyllactose in combination have the potential to induce physiologically relevant increases in γ-aminobutyric and organic acid production along with offsetting the heterogenicity seen in response to sole 2'fucosyllactose supplementation

Food for thought! Inulin-type fructans: does the food matrix matter?

Food matrices can be described as the final composition of a food product which results from complex interactions between compounds found within different ingredients and the processing parameters used in production. These factors, not only impact on the final structure of a product, but also have the potential to alter both the structural integrity and bioavailability of potentially beneficial compounds present, for example, dietary fibres. As a result, there is growing curiosity amongst the scientific community on whether the food matrix may impact on the prebiotic efficacy of inulin-type fructans. Therefore, the purpose of this review is to explore previous food-based inulin-type fructan supplementation studies to determine whether the food matrix directly impacts on their prebiotic efficacy. Our working hypothesis is that other potentially prebiotic ingredients and components present within the food may alter inulin-type fructans prebiotic effect

Breast milk-derived human milk oligosaccharides promote Bifidobacterium interactions within a single ecosystem

Diet-microbe interactions play an important role in modulating the early-life microbiota, with Bifidobacterium strains and species dominating the gut of breast-fed infants. Here, we sought to explore how infant diet drives distinct bifidobacterial community composition and dynamics within individual infant ecosystems. Genomic characterisation of 19 strains isolated from breast-fed infants revealed a diverse genomic architecture enriched in carbohydrate metabolism genes, which was distinct to each strain, but collectively formed a pangenome across infants. Presence of gene clusters implicated in digestion of human milk oligosaccharides (HMOs) varied between species, with growth studies indicating that within single infants there were differences in the ability to utilise 2'FL and LNnT HMOs between strains. Cross-feeding experiments were performed with HMO degraders and non-HMO users (using spent or 'conditioned' media and direct co-culture). Further H-NMR analysis identified fucose, galactose, acetate, and N-acetylglucosamine as key by-products of HMO metabolism; as demonstrated by modest growth of non-HMO users on spend media from HMO metabolism. These experiments indicate how HMO metabolism permits the sharing of resources to maximise nutrient consumption from the diet and highlights the cooperative nature of bifidobacterial strains and their role as 'foundation' species in the infant ecosystem. The intra- and inter-infant bifidobacterial community behaviour may contribute to the diversity and dominance of Bifidobacterium in early life and suggests avenues for future development of new diet and microbiota-based therapies to promote infant health

The potential role of human milk oligosaccharides in irritable bowel syndrome

Irritable Bowel Syndrome (IBS) is the most common gastrointestinal (GI) disorder in Western populations and therefore a major public health/economic concern. However, despite extensive research, psychological and physiological factors that contribute to the aetiology of IBS remain poorly understood. Consequently, clinical management of IBS is reduced to symptom management through various suboptimal options. Recent evidence has suggested human milk oligosaccharides (HMOs) as a potential therapeutic option for IBS. Here, we review literature concerning the role of HMOs in IBS, including data from intervention and in vitro trials. HMO supplementation shows promising results in altering the gut microbiota and improving IBS symptoms, for instance by stimulating bifidobacteria. Further research in adults is required into HMO mechanisms, to confirm the preliminary results available to date and recommendations of HMO use in IBS

Multiplatform characterization of dynamic changes in breast milk during lactation

The multicomponent analysis of human breast milk (BM) by metabolic profiling is a new area of study applied to determining milk composition, and is capable of associating BM composition with maternal characteristics, and subsequent infant health outcomes. A multiplatform approach combining HPLC‐MS and ultra‐performance LC‐MS, GC‐MS, CE‐MS, and 1H NMR spectroscopy was used to comprehensively characterize metabolic profiles from seventy BM samples. A total of 710 metabolites spanning multiple molecular classes were defined. The utility of the individual and combined analytical platforms was explored in relation to numbers of metabolites identified, as well as the reproducibility of the methods. The greatest number of metabolites was identified by the single phase HPLC‐MS method, while CE‐MS uniquely profiled amino acids in detail and NMR was the most reproducible, whereas GC‐MS targeted volatile compounds and short chain fatty acids. Dynamic changes in BM composition were characterized over the first 3 months of lactation. Metabolites identified as altering in abundance over lactation included fucose, di‐ and triacylglycerols, and short chain fatty acids, known to be important for infant immunological, neurological, and gastrointestinal development, as well as being an important source of energy. This extensive metabolic coverage of the dynamic BM metabolome provides a baseline for investigating the impact of maternal characteristics, as well as establishing the impact of environmental and dietary factors on the composition of BM, with a focus on the downstream health consequences this may have for infants

Development of a pipeline for exploratory metabolic profiling of infant urine

Numerous metabolic profiling pipelines have been developed to characterize the composition of human biofluids and tissues, the vast majority of these being for studies in adults. To accommodate limited sample volume and to take into account the compositional differences between adult and infant biofluids, we developed and optimized sample handling and analytical procedures for studying urine from newborns. A robust pipeline for metabolic profiling using NMR spectroscopy was established, encompassing sample collection, preparation, spectroscopic measurement, and computational analysis. Longitudinal samples were collected from five infants from birth until 14 months of age. Methods of extraction and effects of freezing and sample dilution were assessed, and urinary contaminants from breakdown of polymers in a range of diapers and cotton wool balls were identified and compared, including propylene glycol, acrylic acid, and tert-butanol. Finally, assessment of urinary profiles obtained over the first few weeks of life revealed a dramatic change in composition, with concentrations of phenols, amino acids, and betaine altering systematically over the first few months of life. Therefore, neonatal samples require more stringent standardization of experimental design, sample handling, and analysis compared to that of adult samples to accommodate the variability and limited sample volume

Role of government financial support and vulnerability char-acteristics associated with food insecurity during the COVID-19 pandemic among young Peruvians

Peruvian households have experienced one of the most prevalent economic shocks due to COVID-19, significantly increasing their vulnerability to food insecurity (FI). To understand the vulnerability characteristics of these households among the Peruvian young population, including the role of the government’s response through emergency cash transfer, we analysed longitudinal data from the Young Lives study (n=2026) - a study that follows the livelihoods of two birth cohorts currently aged 18 to 27 years old. FI was assessed using the Food Insecurity Experience Scale. Household characteristics were collected before and during the COVID-19 outbreak in Peru to characterize participants’ vulnerability to FI. Multivariate logistic regression was used to evaluate the association between government support and participants’ vulnerability characteristics to FI. During the period under study (March to December 2020), 24% (95% CI:22.1- 25.9%) of the participants experienced FI. Families in the top wealth tercile were 49% less likely to experience FI. Larger families (>5 members) and those with increased household expenses and de-creased income due to COVID-19, were more likely to experience FI (by 35%, 39% and 42%, respectively). There was no significant association between government support and FI (p=0.768). We conclude that pre-pandemic socioeconomic status, family size and the economic disruption during COVID-19 contribute to the risk of FI among the Peruvian young population, while government support insufficiently curtailed the risk to these households

Multi-compartment profiling of cacterial and host metabolites identifies intestinal dysbiosis and its functional consequences in the critically ill child

Adverse physiology and antibiotic exposure devastate the intestinal microbiome in critical illness. Time and cost implications limit the immediate clinical potential of microbial sequencing to identify or treat intestinal dysbiosis. Here, we examined whether metabolic profiling is a feasible method of monitoring intestinal dysbiosis in critically ill children. Prospective multicenter cohort study. Three U.K.-based PICUs. Mechanically ventilated critically ill (n = 60) and age-matched healthy children (n = 55). Collection of urine and fecal samples in children admitted to the PICU. A single fecal and urine sample was collected in healthy controls. Untargeted and targeted metabolic profiling using 1H-nuclear magnetic resonance spectroscopy and liquid chromatography-mass spectrometry or urine and fecal samples. This was integrated with analysis of fecal bacterial 16S ribosomal RNA profiles and clinical disease severity indicators. We observed separation of global urinary and fecal metabolic profiles in critically ill compared with healthy children. Urinary excretion of mammalian-microbial co-metabolites hippurate, 4-cresol sulphate, and formate were reduced in critical illness compared with healthy children. Reduced fecal excretion of short-chain fatty acids (including butyrate, propionate, and acetate) were observed in the patient cohort, demonstrating that these metabolites also distinguished between critical illness and health. Dysregulation of intestinal bile metabolism was evidenced by increased primary and reduced secondary fecal bile acid excretion. Fecal butyrate correlated with days free of intensive care at 30 days (r = 0.38; p = 0.03), while urinary formate correlated inversely with vasopressor requirement (r = -0.2; p = 0.037). Disruption to the functional activity of the intestinal microbiome may result in worsening organ failure in the critically ill child. Profiling of bacterial metabolites in fecal and urine samples may support identification and treatment of intestinal dysbiosis in critical illness.This is an open access article distributed under the Creative Commons Attribution License 4.0 (CCBY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited