Browsing by Author "Young W"
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- ItemAdaptation of the infant gut microbiome during the complementary feeding transition(PLOS, 2022-07-14) McKeen S; Roy NC; Mullaney JA; Eriksen H; Lovell A; Kussman M; Young W; Fraser K; Wall CR; McNabb WC; xia YThe infant gut microbiome progresses in composition and function during the introduction of solid foods throughout the first year of life. The purpose of this study was to characterize changes in healthy infant gut microbiome composition, metagenomic functional capacity, and associated metabolites over the course of the complementary feeding period. Fecal samples were obtained at three 'snapshot' timepoints from infants participating in the 'Nourish to Flourish' pilot study: before the introduction of solid foods at approximately 4 months of age, after introducing solid foods at 9 months of age, and after continued diet diversification at 12 months of age. KEGG and taxonomy assignments were correlated with LC-MS metabolomic profiles to identify patterns of co-abundance. The composition of the microbiome diversified during the first year of life, while the functional capacity present in the gut microbiome remained stable. The introduction of solid foods between 4 and 9 months of age corresponded to a larger magnitude of change in relative abundance of sequences assigned to KEGG pathways and taxonomic assignments, as well as to stronger correlations with metabolites, compared to the magnitude of changes and number of correlations seen during continued diet diversification between 9 and 12 months of age. Changes in aqueous fecal metabolites were more strongly correlated with KEGG pathway assignments, while changes in lipid metabolites associated with taxonomic assignments, particularly between 9 and 12 months of age. This study establishes trends in microbiome composition and functional capacity occurring during the complementary feeding period and identifies potential metabolite targets for future investigations.
- ItemComplete Annotated Genome Sequence of Limosilactobacillus fermentum AGR1487.(American Society for Microbiology, 2021-01-07) Bailie MA; Altermann E; Young W; Roy NC; McNabb WC; Putonti CLimosilactobacillus fermentum is a probiotic species; however, L. fermentum AGR1487 increases colon inflammation in germfree mice and decreases barrier integrity in Caco-2 cells. The AGR1487 genome was sequenced to explore these phenotypes. The genome is a single, circular, 1,939,032-bp chromosome with a G+C content of 52.17% and no plasmids.
- ItemComplete Genome Sequence of Lactobacillus fermentum Strain AGR1485, a Human Oral Isolate.(American Society for Microbiology, 2020-09-03) Bailie MA; Altermann E; Young W; Roy NC; McNabb WC; Gill SRLactobacillus fermentum is found in food products and is generally considered safe. L. fermentum AGR1485 promotes barrier integrity in Caco-2 cells and has genetic similarities to other known probiotic L. fermentum strains. L. fermentum AGR1485 has potential as a probiotic and was sequenced to explore these probiotic properties. The genome is a 2.2-Mbp circular chromosome with no plasmids and a GC content of 51.15%.
- ItemConcentrations of Fecal Bile Acids in Participants with Functional Gut Disorders and Healthy Controls(MDPI (Basel, Switzerland), 2021-09-09) James SC; Fraser K; Young W; Heenan PE; Gearry RB; Keenan JI; Talley NJ; Joyce SA; McNabb WC; Roy NC; Apidianakis Y; Agapiou ABile acids are metabolites involved in nutrient absorption and signaling with levels influenced by dietary intake, metabolic processes, and the gut microbiome. We aimed to quantify 23 bile acids in fecal samples to ascertain if concentrations differed between healthy participants and those with functional gut disorders. Fecal bile acids were measured using liquid chromatography-mass spectrometry (LC-MS) in the COMFORT (The Christchurch IBS cohort to investigate mechanisms for gut relief and improved transit) cohort of 250 participants with Rome IV IBS (IBS-constipation (C), IBS-diarrhea (D), IBS-mixed (M)), functional gut disorders (functional constipation (FC), functional diarrhea (FD)) and healthy controls (FC n = 35, FD n = 13, IBS-C n = 24, IBS-D n = 52, IBS-M n = 29, and control n = 97). Dietary information was recorded to ascertain three-day dietary intake before fecal samples were collected. Fecal bile acid concentrations, predominantly primary bile acids, were significantly different between all functional gut disorder participants and healthy controls (CDCA p = 0.011, CA p = 0.003) and between constipation (FC + IBS-C) and diarrhea (FD + IBS-D) groups (CDCA p = 0.001, CA p = 0.0002). Comparison of bile acids between all functional groups showed four metabolites were significantly different, although analysis of combined groups (FC + IBS-C vs. FD + IBS-D) showed that 10 metabolites were significantly different. The bile acid profiles of FD individuals were similar to those with IBS-D, and likewise, those with FC were similar to IBS-C. Individuals with a diarrhea phenotype (FD + IBS-D) had higher concentrations of bile acids compared to those with constipation (FC + IBS-C). Bile acid metabolites distinguish between individuals with functional gut disorders and healthy controls but are similar in constipation (or diarrhea) whether classified as IBS or not.
- ItemConcentrations of Plasma Amino Acids and Neurotransmitters in Participants with Functional Gut Disorders and Healthy Controls(MDPI (Basel, Switzerland), 2023-02-20) James SC; Fraser K; Cooney J; Günther CS; Young W; Gearry RB; Heenan PE; Trower T; Keenan JI; Talley NJ; McNabb WC; Roy NC; Jang CAmino acids are important in several biochemical pathways as precursors to neurotransmitters which impact biological processes previously linked to functional gastrointestinal disorders (FGIDs). Dietary protein consumption, metabolic host processes, and the gut microbiome can influence the plasma concentration of amino acids and neurotransmitters, and their uptake by tissues. The aim of this analysis was to quantify 19 proteogenic and 4 non-proteogenic amino acids and 19 neurotransmitters (including precursors and catabolites, herein referred to as neurotransmitters) to ascertain if their circulating concentrations differed between healthy participants and those with FGIDs. Plasma proteogenic and non-proteogenic amino acids and neurotransmitters were measured using ultra-performance liquid chromatography and liquid chromatography-mass spectrometry, respectively, from 165 participants (Rome IV: irritable bowel syndrome (IBS-constipation, IBS-diarrhea), functional constipation, functional diarrhea, and healthy controls). There were significant differences (p < 0.05) in pairwise comparisons between healthy controls and specific FGID groups for branched-chain amino acids (BCAAs), ornithine, and alpha-aminobutyric acid. No other significant differences were observed for the neurotransmitters or any other amino acids analyzed. Multivariate and bivariate correlation analyses between proteogenic and non-proteogenic amino acids and neurotransmitters for constipation (constipation (IBS-C and functional constipation) and phenotypes diarrhea (IBS-D and functional diarrhea)) and healthy controls suggested that associations between BCAAs, 5-hydroxytryptophan, and kynurenine in combination with tyrosine, 3,4-dihydroxyphenylalanine, and 3,4-dihydroxyphenylacetic acid and associations with gamma-aminobutyric acid, glutamate, asparagine, and serine are likely disrupted in FGID phenotypes. In conclusion, although correlations were evident between some proteogenic and non-proteogenic amino acids and neurotransmitters, the results showed minor concentration differences in plasma proteogenic and non-proteogenic amino acids, amino acid-derived metabolites, and neurotransmitters between FGID phenotypes and healthy controls.
- ItemDietary format alters fecal bacterial populations in the domestic cat (Felis catus)(John Wiley and Sons, 2013) Bermingham EN; Young W; Kittelmann S; Kerr KR; Swanson KS; Roy NC; Thomas DGThe effects of short-term (5-week) exposure to wet or dry diets on fecal bacterial populations in the cat were investigated. Sixteen mixed-sex, neutered, domestic short-haired cats (mean age = 6 years; mean bodyweight = 3.4 kg) were randomly allocated to wet or dry diets in a crossover design. Fecal bacterial DNA was isolated and bacterial 16S rRNA gene amplicons generated and analyzed by 454 Titanium pyrosequencing. Cats fed dry diets had higher abundances (P < 0.05) of Actinobacteria (16.5% vs. 0.1%) and lower abundances of Fusobacteria (0.3% vs. 23.1%) and Proteobacteria (0.4% vs. 1.1%) compared with cats fed the wet diet. Of the 46 genera identified, 30 were affected (P < 0.05) by diet, with higher abundances of Lactobacillus (31.8% vs. 0.1%), Megasphaera (23.0% vs. 0.0%), and Olsenella (16.4% vs. 0.0%), and lower abundances of Bacteroides (0.6% vs. 5.7%) and Blautia (0.3% vs. 2.3%) in cats fed the dry diet compared with cats fed the wet diet. These results demonstrate that short-term dietary exposure to diet leads to large shifts in fecal bacterial populations that have the potential to affect the ability of the cat to process macronutrients in the diet.
- ItemEffects of early postnatal life nutritional interventions on immune-microbiome interactions in the gastrointestinal tract and implications for brain development and function(Frontiers Media S A, 2022-11-23) Mullaney JA; Roy NC; Halliday C; Young W; Altermann E; Kruger MC; Dilger RN; McNabb WC; Wang HThe gastrointestinal (GI) microbiota has co-evolved with the host in an intricate relationship for mutual benefit, however, inappropriate development of this relationship can have detrimental effects. The developing GI microbiota plays a vital role during the first 1,000 days of postnatal life, during which occurs parallel development and maturation of the GI tract, immune system, and brain. Several factors such as mode of delivery, gestational age at birth, exposure to antibiotics, host genetics, and nutrition affect the establishment and resultant composition of the GI microbiota, and therefore play a role in shaping host development. Nutrition during the first 1,000 days is considered to have the most potential in shaping microbiota structure and function, influencing its interactions with the immune system in the GI tract and consequent impact on brain development. The importance of the microbiota-GI-brain (MGB) axis is also increasingly recognized for its importance in these developmental changes. This narrative review focuses on the importance of the GI microbiota and the impact of nutrition on MGB axis during the immune system and brain developmental period in early postnatal life of infants.
- ItemGlycan Utilisation and Function in the Microbiome of Weaning Infants(MDPI (Basel, Switzerland), 2019-07-04) McKeen S; Young W; Fraser K; Roy NC; McNabb WCGlycans are present exogenously in the diet, expressed and secreted endogenously by host cells, and produced by microbes. All of these processes result in them being available to the gut microbiome, firmly placing glycans at the interface of diet-microbe-host interactions. The most dramatic shift in dietary sources of glycans occurs during the transition from the milk-based neonatal diet to the diverse omnivorous adult diet, and this has profound effects on the composition of the gut microbiome, gene expression by microbes and host cells, mucin composition, and immune development from innate towards adaptive responses. Understanding the glycan-mediated interactions occurring during this transitional window may inform dietary recommendations to support gut and immune development during a vulnerable age. This review aims to summarise the current state of knowledge on dietary glycan mediated changes that may occur in the infant gut microbiome and immune system during weaning.
- ItemGut Microbial Metabolites and Biochemical Pathways Involved in Irritable Bowel Syndrome: Effects of Diet and Nutrition on the Microbiome(Elsevier Inc on behalf of the American Society for Nutrition, 2020-05) James SC; Fraser K; Young W; McNabb WC; Roy NCThe food we consume and its interactions with the host and their gut microbiota affect normal gut function and health. Functional gut disorders (FGDs), including irritable bowel syndrome (IBS), can result from negative effects of these interactions, leading to a reduced quality of life. Certain foods exacerbate or reduce the severity and prevalence of FGD symptoms. IBS can be used as a model of perturbation from normal gut function with which to study the impact of foods and diets on the severity and symptoms of FGDs and understand how critical processes and biochemical mechanisms contribute to this impact. Analyzing the complex interactions between food, host, and microbial metabolites gives insights into the pathways and processes occurring in the gut which contribute to FGDs. The following review is a critical discussion of the literature regarding metabolic pathways and dietary interventions relevant to FGDs. Many metabolites, for example bile acids, SCFAs, vitamins, amino acids, and neurotransmitters, can be altered by dietary intake, and could be valuable for identifying perturbations in metabolic pathways that distinguish a "normal, healthy" gut from a "dysfunctional, unhealthy" gut. Dietary interventions for reducing symptoms of FGDs are becoming more prevalent, but studies investigating the underlying mechanisms linked to host, microbiome, and metabolite interactions are less common. Therefore, we aim to evaluate the recent literature to assist with further progression of research in this field.
- ItemGut-Brain Axis in the Early Postnatal Years of Life: A Developmental Perspective(Frontiers Media S.A., 2020-08-05) Jena A; Montoya CA; Mullaney JA; Dilger RN; Young W; McNabb WC; Roy NC; Cammarota MEmerging evidence suggests that alterations in the development of the gastrointestinal (GI) tract during the early postnatal period can influence brain development and vice-versa. It is increasingly recognized that communication between the GI tract and brain is mainly driven by neural, endocrine, immune, and metabolic mediators, collectively called the gut-brain axis (GBA). Changes in the GBA mediators occur in response to the developmental changes in the body during this period. This review provides an overview of major developmental events in the GI tract and brain in the early postnatal period and their parallel developmental trajectories under physiological conditions. Current knowledge of GBA mediators in context to brain function and behavioral outcomes and their synthesis and metabolism (site, timing, etc.) is discussed. This review also presents hypotheses on the role of the GBA mediators in response to the parallel development of the GI tract and brain in infants.
- ItemIn Vitro Assessment of Hydrolysed Collagen Fermentation Using Domestic Cat (Felis catus) Faecal Inocula(MDPI (Basel, Switzerland), 2022-02-17) Butowski CF; Thomas DG; Cave NJ; Bermingham EN; Rosendale DI; Hea S-Y; Stoklosinski HM; Young W; Ebani VVThe gastrointestinal microbiome has a range of roles in the host, including the production of beneficial fermentation end products such as butyrate, which are typically associated with fermentation of plant fibres. However, domestic cats are obligate carnivores and do not require carbohydrates. It has been hypothesised that in the wild, collagenous parts of prey-the so-called animal-derived fermentable substrates (ADFS) such as tendons and cartilage-may be fermented by the cat's gastrointestinal microbiome. However, little research has been conducted on ADFS in the domestic cat. Faecal inoculum was obtained from domestic cats either consuming a high carbohydrate (protein:fat:carbohydrate ratio of 35:20:28 (% dry matter basis)) or high protein (protein:fat:carbohydrate ratio of 75:19:1 (% dry matter basis)) diet. ADFS (hydrolysed collagen, cat hair, and cartilage) were used in a series of static in vitro digestions and fermentations. Concentrations of organic acids and ammonia were measured after 24 h of fermentation, and the culture community of microbes was characterised. The type of inoculum used affected the fermentation profile produced by the ADFS. Butyrate concentrations were highest when hydrolysed collagen was fermented with high protein inoculum (p < 0.05). In contrast, butyrate was not detectable when hydrolysed collagen was fermented in high carbohydrate inoculum (p < 0.05). The microbiome of the domestic cat may be able to ferment ADFS to provide beneficial concentrations of butyrate.
- ItemIn vitro Fermentation of Digested Milk Fat Globule Membrane From Ruminant Milk Modulates Piglet Ileal and Caecal Microbiota(Frontiers Media S.A., 2020-07-09) Thum C; Young W; Montoya CA; Roy NC; McNabb WC; Benítez-Páez ALipids in milk are secreted as a triacylglycerol core surrounded by a trilayer membrane, the milk fat globule membrane (MFGM). This membrane, known to have important roles in infant brain and intestinal development, is composed of proteins, glycoproteins, and complex lipids. We hypothesized that some of the beneficial properties of MFGM are due to its effects on the gastrointestinal microbiota. This study aimed to determine the effect of a commercial phospholipid concentrate (PC) and enriched bovine, caprine, and ovine MFGM fractions on ileal and hindgut microbiota in vitro. Digestion of PC and MFGMs was conducted using an in vitro model based on infant gastric and small intestine conditions. The recovered material was then in vitro fermented with ileal and caecal inocula prepared from five piglets fed a commercial formula for 20 days before ileal and caecal digesta were collected. After each fermentation, samples were collected to determine organic acid production and microbiota composition using 16S rRNA sequencing. All substrates, except PC (5%), were primarily fermented by the ileal microbiota (8-14%) (P < 0.05). PC and caprine MFGM reduced ileal microbiota alpha diversity compared to ileal inoculum. Caprine MFGM increased and PC reduced the ileal ratio of firmicutes:proteobacteria (P < 0.05), respectively, compared to the ileal inoculum. Bovine and ovine MFGMs increased ileal production of acetic, butyric, and caproic acids compared to other substrates and reduced the proportions of ileal proteobacteria (P < 0.0001). There was a limited fermentation of bovine (3%), caprine (2%), and ovine (2%) MFGMs by the caecal microbiota compared to PC (14%). In general, PC and all MFGMs had a reduced effect on caecal microbiota at a phylum level although MFG source-specific effects were observed at the genus level. These indicate that the main effects of the MFGM in the intestinal microbial population appears to occur in the ileum.
- ItemIn Vitro Fermentation of Sheep and Cow Milk Using Infant Fecal Bacteria(MDPI (Basel, Switzerland), 2020-06-17) Ahlborn N; Young W; Mullaney J; Samuelsson LMWhile human milk is the optimal food for infants, formulas that contain ruminant milk can have an important role where breastfeeding is not possible. In this regard, cow milk is most commonly used. However, recent years have brought interest in other ruminant milk. While many similarities exist between ruminant milk, there are likely enough compositional differences to promote different effects in the infant. This may include effects on different bacteria in the large bowel, leading to different metabolites in the gut. In this study sheep and cow milk were digested using an in vitro infant digestive model, followed by fecal fermentation using cultures inoculated with fecal material from two infants of one month and five months of age. The effects of the cow and sheep milk on the fecal microbiota, short-chain fatty acids (SCFA), and other metabolites were investigated. Significant differences in microbial, SCFA, and metabolite composition were observed between fermentation of sheep and cow milk using fecal inoculum from a one-month-old infant, but comparatively minimal differences using fecal inoculum from a five-month-old infant. These results show that sheep milk and cow milk can have differential effects on the gut microbiota, while demonstrating the individuality of the gut microbiome.
- ItemIncreasing Evidence That Irritable Bowel Syndrome and Functional Gastrointestinal Disorders Have a Microbial Pathogenesis(Frontiers Media S.A., 2020-09-09) Carco C; Young W; Gearry RB; Talley NJ; McNabb WC; Roy NC; Ianiro GThe human gastrointestinal tract harbors most of the microbial cells inhabiting the body, collectively known as the microbiota. These microbes have several implications for the maintenance of structural integrity of the gastrointestinal mucosal barrier, immunomodulation, metabolism of nutrients, and protection against pathogens. Dysfunctions in these mechanisms are linked to a range of conditions in the gastrointestinal tract, including functional gastrointestinal disorders, ranging from irritable bowel syndrome, to functional constipation and functional diarrhea. Irritable bowel syndrome is characterized by chronic abdominal pain with changes in bowel habit in the absence of morphological changes. Despite the high prevalence of irritable bowel syndrome in the global population, the mechanisms responsible for this condition are poorly understood. Although alterations in the gastrointestinal microbiota, low-grade inflammation and immune activation have been implicated in the pathophysiology of functional gastrointestinal disorders, there is inconsistency between studies and a lack of consensus on what the exact role of the microbiota is, and how changes to it relate to these conditions. The complex interplay between host factors, such as microbial dysbiosis, immune activation, impaired epithelial barrier function and motility, and environmental factors, including diet, will be considered in this narrative review of the pathophysiology of functional gastrointestinal disorders.
- ItemInfant Complementary Feeding of Prebiotics for the Microbiome and Immunity(MDPI (Basel, Switzerland), 2019-02-09) McKeen S; Young W; Mullaney J; Fraser K; McNabb WC; Roy NCComplementary feeding transitions infants from a milk-based diet to solid foods, providing essential nutrients to the infant and the developing gut microbiome while influencing immune development. Some of the earliest microbial colonisers readily ferment select oligosaccharides, influencing the ongoing establishment of the microbiome. Non-digestible oligosaccharides in prebiotic-supplemented formula and human milk oligosaccharides promote commensal immune-modulating bacteria such as Bifidobacterium, which decrease in abundance during weaning. Incorporating complex, bifidogenic, non-digestible carbohydrates during the transition to solid foods may present an opportunity to feed commensal bacteria and promote balanced concentrations of beneficial short chain fatty acid concentrations and vitamins that support gut barrier maturation and immunity throughout the complementary feeding window.
- ItemLipidomics of Brain Tissues in Rats Fed Human Milk from Chinese Mothers or Commercial Infant Formula(MDPI (Basel, Switzerland), 2019-10-28) Su M; Subbaraj AK; Fraser K; Qi X; Jia H; Chen W; Gomes Reis M; Agnew M; Day L; Roy NC; Young WHolistic benefits of human milk to infants, particularly brain development and cognitive behavior, have stipulated that infant formula be tailored in composition like human milk. However, the composition of human milk, especially lipids, and their effects on brain development is complex and not fully elucidated. We evaluated brain lipidome profiles in weanling rats fed human milk or infant formula using non-targeted UHPLC-MS techniques. We also compared the lipid composition of human milk and infant formula using conventional GC-FID and HPLC-ELSD techniques. The sphingomyelin class of lipids was significantly higher in brains of rats fed human milk. Lipid species mainly comprising saturated or mono-unsaturated C18 fatty acids contributed significantly higher percentages to their respective classes in human milk compared to infant formula fed samples. In contrast, PUFAs contributed significantly higher percentages in brains of formula fed samples. Differences between human milk and formula lipids included minor fatty acids such as C8:0 and C12:0, which were higher in formula, and C16:1 and C18:1 n11, which were higher in human milk. Formula also contained higher levels of low- to medium-carbon triacylglycerols, whereas human milk had higher levels of high-carbon triacylglycerols. All phospholipid classes, and ceramides, were higher in formula. We show that brain lipid composition differs in weanling rats fed human milk or infant formula, but dietary lipid compositions do not necessarily manifest in the brain lipidome.
- ItemMetabolite profiling of peripheral blood plasma in pigs in early postnatal life fed whole bovine, caprine or ovine milk(Frontiers Media S.A., 2023-09-26) Jena A; Montoya CA; Fraser K; Giezenaar C; Young W; Mullaney JA; Dilger RN; Roy D; McNabb WC; Roy NC; Leroux CRuminants' milk is commonly used for supplying nutrients to infants when breast milk is unavailable or limited. Previous studies have highlighted the differences between ruminants' milk composition, digestion, absorption, and fermentation. However, whether consuming different ruminants' milk impact the appearance of the circulatory blood metabolites in the early postnatal life is not well understood. The analysis conducted here aimed to determine the effect of feeding exclusively whole milk from bovine, caprine or ovine species to pigs, approximately 7 days-old for 15 days, on circulatory blood plasma metabolites. Relative intensities of plasma metabolites were detected using a liquid chromatography-mass spectrometry based metabolomic approach. Seven polar and 83 non-polar (lipids) metabolites in plasma were significantly different (false discovery rate < 0.05) between milk treatments. These included polar metabolites involved in amino acid metabolism and lipids belonging to phosphatidylcholine, lysophosphatidylcholine, sphingomyelin, and triglycerides. Compared to the caprine or bovine milk group, the relative intensities of polar metabolites and unsaturated triglycerides were higher in the peripheral circulation of the ovine milk group. In contrast, relative intensities of saturated triglycerides and phosphatidylcholine were higher in the bovine milk group compared to the ovine or caprine milk group. In addition, correlations were identified between amino acid and lipid intake and their appearance in peripheral blood circulation. The results highlighted that consuming different ruminants' milk influences the plasma appearance of metabolites, especially lipids, that may contribute to early postnatal life development in pigs.
- ItemMetabolome and microbiome profiling of a stress-sensitive rat model of gut-brain axis dysfunction(Springer Nature Limited, 2019-10-01) Bassett SA; Young W; Fraser K; Dalziel JE; Webster J; Ryan L; Fitzgerald P; Stanton C; Dinan TG; Cryan JF; Clarke G; Hyland N; Roy NCStress negatively impacts gut and brain health. Individual differences in response to stress have been linked to genetic and environmental factors and more recently, a role for the gut microbiota in the regulation of stress-related changes has been demonstrated. However, the mechanisms by which these factors influence each other are poorly understood, and there are currently no established robust biomarkers of stress susceptibility. To determine the metabolic and microbial signatures underpinning physiological stress responses, we compared stress-sensitive Wistar Kyoto (WKY) rats to the normo-anxious Sprague Dawley (SD) strain. Here we report that acute stress-induced strain-specific changes in brain lipid metabolites were a prominent feature in WKY rats. The relative abundance of Lactococcus correlated with the relative proportions of many brain lipids. In contrast, plasma lipids were significantly elevated in response to stress in SD rats, but not in WKY rats. Supporting these findings, we found that the greatest difference between the SD and WKY microbiomes were the predicted relative abundance of microbial genes involved in lipid and energy metabolism. Our results provide potential insights for developing novel biomarkers of stress vulnerability, some of which appear genotype specific.
- Item"Nourish to Flourish": complementary feeding for a healthy infant gut microbiome-a non-randomised pilot feasibility study.(Springer Nature Limited., 2022-05-18) Lovell AL; Eriksen H; McKeen S; Mullaney J; Young W; Fraser K; Altermann E; Gasser O; Kussmann M; Roy NC; McNabb WC; Wall CRBACKGROUND: The introduction of complementary foods and changes in milk feeding result in modifications to gastrointestinal function. The interplay between indigestible carbohydrates, host physiology, and microbiome, and immune system development are areas of intense research relevant to early and later-life health. METHODS: This 6-month prospective non-randomised feasibility study was conducted in Auckland, New Zealand (NZ), in January 2018. Forty parents/caregivers and their infants were enrolled, with 30 infants allocated to receive a prebiotic NZ kūmara (flesh and skin; a type of sweet potato) prepared as a freeze-dried powder, and ten infants allocated to receive a commercially available probiotic control known to show relevant immune benefits (109 CFU Bifidobacterium lactis BB-12®). The primary outcome was the study feasibility measures which are reported here. RESULTS: Recruitment, participant retention, and data collection met feasibility targets. Some limitations to biological sample collection were encountered, with difficulties in obtaining sufficient plasma sample volumes for the proposed immune parameter analyses. Acceptability of the kūmara powder was met with no reported adverse events. CONCLUSION: This study indicates that recruiting infants before introducing complementary foods is feasible, with acceptable adherence to the food-based intervention. These results will inform the protocol of a full-scale randomised controlled trial (RCT) with adjustments to the collection of biological samples to examine the effect of a prebiotic food on the prevalence of respiratory tract infections during infancy. Trial registration Australia New Zealand Clinical Trials Registry ACTRN12618000157279 . Prospectively registered on 02/01/2018.
- ItemNourishing the Infant Gut Microbiome to Support Immune Health: Protocol of SUN (Seeding Through Feeding) Randomized Controlled Trial.(JMIR Publications, 2024-09-02) Wall CR; Roy NC; Mullaney JA; McNabb WC; Gasser O; Fraser K; Altermann E; Young W; Cooney J; Lawrence R; Jiang Y; Galland BC; Fu X; Tonkie JN; Mahawar N; Lovell AL; Ma SBackground: The introduction of complementary foods during the first year of life influences the diversity of the gut microbiome. How this diversity affects immune development and health is unclear. Objective: This study evaluates the effect of consuming kūmara or kūmara with added banana powder (resistant starch) compared to a reference control at 4 months post randomization on the prevalence of respiratory tract infections and the development of the gut microbiome. Methods: This study is a double-blind, randomized controlled trial of mothers and their 6-month-old infants (up to n=300) who have not yet started solids. Infants are randomized into one of 3 groups: control arm (C), standard kūmara intervention (K), and a kūmara intervention with added banana powder product (K+) to be consumed daily for 4 months until the infant is approximately 10 months old. Infants are matched for sex using stratified randomization. Data are collected at baseline (prior to commencing solid food) and at 2 and 4 months after commencing solid food (at around 8 and 10 months of age). Data and samples collected at each timepoint include weight and length, intervention adherence (months 2 and 4), illness and medication history, dietary intake (months 2 and 4), sleep (diary and actigraphy), maternal dietary intake, breast milk, feces (baseline and 4 months), and blood samples (baseline and 4 months). Results: The trial was approved by the Health and Disability Ethics Committee of the Ministry of Health, New Zealand (reference 20/NTA/9). Recruitment and data collection did not commence until January 2022 due to the COVID-19 pandemic. Data collection and analyses are expected to conclude in January 2024 and early 2025, respectively. Results are to be published in 2024 and 2025. Conclusions: The results of this study will help us understand how the introduction of a specific prebiotic complementary food affects the microbiota and relative abundances of the microbial species, the modulation of immune development, and infant health. It will contribute to the expanding body of research that aims to deepen our understanding of the connections between nutrition, gut microbiota, and early-life postnatal health. Trial Registration: Australian New Zealand Clinical Trials Registry ACTRN12620000026921; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=378654 International Registered Report Identifier (IRRID): DERR1-10.2196/56772 JMIR Res Protoc 2024;13:e56772