Gut Bacteria Research Articles

Health Benefits of Prebiotics, Probiotics, Synbiotics, and Postbiotics.

The trillions of microbes that constitute the human gut microbiome play a crucial role in digestive health, immune response regulation, and psychological wellness. Maintaining gut microbiota is essential as metabolic diseases are associated with it. Functional food ingredients potentially improving gut health include prebiotics, probiotics, synbiotics, and postbiotics (PPSPs). While probiotics are living bacteria that provide health advantages when ingested sufficiently, prebiotics are non-digestible carbohydrates that support good gut bacteria. Synbiotics work together to improve immunity and intestinal health by combining probiotics and prebiotics. Postbiotics have also demonstrated numerous health advantages, such as bioactive molecules created during probiotic fermentation. According to a recent study, PPSPs can regulate the synthesis of metabolites, improve the integrity of the intestinal barrier, and change the gut microbiota composition to control metabolic illnesses. Additionally, the use of fecal microbiota transplantation (FMT) highlights the potential for restoring gut health through microbiota modulation, reinforcing the benefits of PPSPs in enhancing overall well-being. Research has shown that PPSPs provide several health benefits, such as improved immunological function, alleviation of symptoms associated with irritable bowel disease (IBD), decreased severity of allergies, and antibacterial and anti-inflammatory effects. Despite encouraging results, many unanswered questions remain about the scope of PPSPs' health advantages. Extensive research is required to fully realize the potential of these functional food components in enhancing human health and well-being. Effective therapeutic and prophylactic measures require further investigation into the roles of PPSPs, specifically their immune-system-modulating, cholesterol-lowering, antioxidant, and anti-inflammatory characteristics.

Metabolic outcomes of Cordyceps fungus and Goji plant polysaccharides during in vitro human fecal fermentation

This study was to assess the digestion and colonic fermentation of two bioactive polysaccharides, EPS-LM and LBPS, and the subsequent influences on human gut microbiota through simulated gastrointestinal systems. EPS-LM, an exopolysaccharide isolated from mycelial culture of a medicinal fungus Cordyceps sinensis Cs-HK1, was characterized as a heteropolysaccharide consisting of Man(108):Gal(52.7):Glc(29.2) (molar ratio) with an average molecular weight (MW) 5.513 × 106. LBPS was isolated from a well-known medicinal plant (Lycium barbarum L.) which was also characterized as a heteropolysaccharide (1.236 × 105 MW). Both polysaccharides were highly resistant to saliva, gastric and small-intestine digestion with negligible MW reduction and release of reducing sugars but were quickly degraded to lower MW during in vitro human fecal fermentation. They were consumed as a carbon source by the gut bacteria to produce short-chain fatty acids (SCFAs). In comparison, the carbohydrate content of EPS-LM was more completely consumed than LBPS and there were also notable differences in consumption of specific monosaccharides and production of specific SCFAs, propionic and butyric acid, and relative abundance of gut bacterial populations between EPS-LM and LBPS group. The results suggest that metabolic outcomes and modulating effects of EPS-LM and LBPS on the gut microbiota are highly dependent on their molecular composition.

The Microbiome-Genetics Axis in Autism Spectrum Disorders: A Probiotic Perspective.

Autism spectrum disorder (commonly known as autism) is a complex and prevalent neurodevelopmental condition characterized by challenges in social behavior, restricted interests, and repetitive behaviors. It is projected that the annual cost of autism spectrum disorder in the US will reach USD 461 billion by 2025. However, despite being a major public health problem, effective treatment for the underlying symptoms remains elusive. As numerous literature data indicate the role of gut microbiota in autism prognosis, particularly in terms of alleviating gastrointestinal (GI) symptoms, high hopes have been placed on probiotics for autism treatment. Approximately twenty clinical studies have been conducted using single or mixed probiotic cultures. However, unequivocal results on the effect of probiotics on people with autism have not been obtained. The small sample sizes, differences in age of participants, choice of probiotics, dose and duration of treatment, outcome measures, and analytical methods used are largely inconsistent, making it challenging to draw distinctive conclusions. Here, we discuss the experimental evidence for specific gut bacteria and their metabolites and how they affect autism in light of the phenotypic and etiological complexity and heterogeneity. We propose a personalized medicine approach for using probiotics to increase the quality of life of individuals with autism by selecting specific probiotics to improve particular features of the condition.

Salinity mediates the damage caused by acute and chronic ammonia stress in largemouth bass (Micropterus salmoides)

Ammonia is a critical pollutant in aquatic environments, posing significant risks to aquaculture by accumulating in culture systems due to fish excretion and organic matter decomposition. This study investigated the effects of ammonia toxicity on juvenile largemouth bass (Micropterus salmoides) under varying salinity conditions (0 and 5 psu), focusing on physiological responses and gut microbiota changes. Results indicated that ammonia exposure led to increased mortality, oxidative stress, liver damage, and significant shifts in gut microbial communities, especially under freshwater conditions. Elevated salinity mitigated these effects by reducing the bioavailability of toxic un-ionized ammonia (UIA) and enhancing the fish's physiological resilience, particularly in the kidney and intestine. Ammonia exposure significantly increased the IBR index values in all three organs, with the gills showing the most pronounced stress response, followed by the kidney and intestine. Salinity had a significant mitigating effect by reducing the oxidative stress response in comparison to freshwater conditions. However, in the gills, the protective effect of salinity was not enough to fully counteract the oxidative stress induced by ammonia. Ammonia exposure in freshwater favored pathogenic gut bacteria genera such as Aeromonas, while higher salinity enriched stress-resistant genera like Ralstonia and Klebsiella. These findings contribute to a better understanding of the interaction between salinity and ammonia toxicity, suggesting that moderate salinity increases within the fish's tolerance range could be an effective strategy in aquaculture to reduce ammonia toxicity and promote fish health.

Sugar Composition of Thai Desserts and Their Impact on the Gut Microbiome in Healthy Volunteers: A Randomized Controlled Trial.

The relationship between consuming Thai desserts-predominantly composed of carbohydrates-and gut microbiome profiles remains unclear. This study aimed to evaluate the effects of consuming various Thai desserts with different GI values on the gut microbiomes of healthy volunteers. This open-label, parallel randomized clinical trial involved 30 healthy individuals aged 18 to 45 years. Participants were randomly assigned to one of three groups: Phetchaburi's Custard Cake (192 g, low-GI group, n = 10), Saraburi's Curry Puff (98 g, medium-GI group, n = 10), and Lampang's Crispy Rice Cracker (68 g, high-GI group, n = 10), each consumed alongside their standard breakfast. Fecal samples were collected at baseline and 24 h post-intervention for metagenomic analysis of gut microbiome profiles using 16S rRNA gene sequencing. After 24 h, distinct trends in the relative abundance of various gut microbiota were observed among the dessert groups. In the high-GI dessert group, the abundance of Collinsella and Bifidobacterium decreased compared to the low- and medium-GI groups, while Roseburia and Ruminococcus showed slight increases. Correlation analysis revealed a significant negative relationship between sugar intake and Lactobacillus abundance in the medium- and high-GI groups, but not in the low-GI group. Additionally, a moderately negative association was observed between Akkermansia abundance and sugar intake in the high-GI group. These bacteria are implicated in energy metabolism and insulin regulation. LEfSe analysis identified Porphyromonadaceae and Porphyromonas as core microbiota in the low-GI group, whereas Klebsiella was enriched in the high-GI group, with no predominant bacteria identified in the medium-GI group. The findings suggest that Thai desserts with varying GI levels can influence specific gut bacteria, though these effects may be temporary.

Gut microbial composition differs among FUNAAB Alpha broiler chicken genotypes raised in a tropical environment

The gut microbiota of FUNAAB Alpha chickens plays a crucial role in determining their overall health and performance. Understanding the various types and diversity of microbiota in the gut of different genotypes of chickens is crucial for enhancing their well-being, productivity, and disease resistance. This study employed 16S rRNA and metagenomics analysis to examine the gut bacteria of three genotypes of FUNAAB Alpha broiler chickens, namely Naked neck, Frizzle, and Normal feather. There were three phyla observed in the three genotypes: Bacteroidetes, Actinobacteria, and Firmicutes. Through the utilisation of 16S rRNA sequencing, we successfully identified and categorised the various microbiota present within the gastrointestinal tract. Our study revealed notable variations in the composition and quantity of microbiota across the three genotypes, suggesting that each genotype possesses a distinct collection of gut bacteria. A wide range of microbiological diversity was observed within the community. Interestingly, the Normal feather chicken exhibited a greater number of operational taxonomic units (OTUs) compared to the Naked neck and Frizzle feather chicken. This study presents significant findings regarding the ceacal microbiota of FUNAAB Alpha chickens, emphasising the variations observed among different genotypes. It is crucial to study composition-modification techniques to enhance host health and performance, as well as to control zoonotic pathogens that can contaminate poultry products and threaten consumers’ health.

Mapping Pesticide-Induced Metabolic Alterations in Human Gut Bacteria.

Pesticides can modulate gut microbiota (GM) composition, but their specific effects on GM remain largely elusive. Our study demonstrated that pesticides inhibit or promote growth in various GM species, even at low concentrations, and can accumulate in GM to prolong their presence in the host. Meanwhile, the pesticide induced changes in GM composition are associated with significant alterations in gut bacterial metabolism that reflected by the changes of hundreds of metabolites. We generated a pesticide-GM-metabolites (PMM) network that not only reveals pesticide-sensitive gut bacteria species but also report specific metabolic changes in 306 pesticide-GM pairs (PGPs). Using an in vivo mice model, we further demonstrated a PGP's interactions and verified the inflammation-inducing effects of pesticides on the host through dysregulated lipid metabolism of microbes. Taken together, our findings generate a PMM interactions atlas, and shed light on the molecular level of how pesticides impact host health by modulating GM metabolism.

Intestinal Insights: The Gut Microbiome's Role in Atherosclerotic Disease: A Narrative Review.

Recent advances have highlighted the gut microbiota as a significant contributor to the development and progression of atherosclerosis, which is an inflammatory cardiovascular disease (CVD) characterized by plaque buildup within arterial walls. The gut microbiota, consisting of a diverse collection of microorganisms, impacts the host's metabolism, immune responses, and lipid processing, all of which contribute to atherosclerosis. This review explores the complex mechanisms through which gut dysbiosis promotes atherogenesis. We emphasize the potential of integrating microbiota modulation with traditional cardiovascular care, offering a holistic approach to managing atherosclerosis. Important pathways involve the translocation of inflammatory microbial components, modulation of lipid metabolism through metabolites such as trimethylamine-N-oxide (TMAO), and the production of short-chain fatty acids (SCFAs) that influence vascular health. Studies reveal distinct microbial profiles in atherosclerosis patients, with increased pathogenic bacteria (Megamonas, Veillonella, Streptococcus) and reduced anti-inflammatory genera (Bifidobacterium, Roseburia), highlighting the potential of these profiles as biomarkers and therapeutic targets. Probiotics are live microorganisms that have health benefits on the host. Prebiotics are non-digestible dietary fibers that stimulate the growth and activity of beneficial gut bacteria. Interventions targeting microbiota, such as probiotics, prebiotics, dietary modifications, and faecal microbiota transplantation (FMT), present effective approaches for restoring microbial equilibrium and justifying cardiovascular risk. Future research should focus on longitudinal, multi-omics studies to clarify causal links and refine therapeutic applications.

A nested case-control study on the association of gut virome in early pregnancy and gestational diabetes mellitus.

Recent studies have increasingly shown the connection between gut microbiome and gestational diabetes mellitus (GDM). However, no studies have explored the relationship between the gut virome and GDM, and the underlying mechanism remains unknown. We performed a nested case-control study within a follow-up cohort, enrolling 51 patients with GDM and 51 healthy controls. Shotgun metagenomics sequencing was used to explore gut virome profiles during early pregnancy. Diversity analysis revealed no difference in the overall gut virome composition between two groups, however, we found greater abundance of Escherichia phage SH2026Stx1 (Q = 0.23), Enterobacteria phage mEp043 c-1 (Q = 0.21), crAssphage cr50_1 (Q = 0.21), Enterobacteria phage phi80 (Q = 0.21), and Escherichia phage HK106 (Q = 0.23) in GDM patients. Cross-kingdom correlation analysis showed the negative correlation between the gut bacterium Eubacterium eligens and three bacteriophages (Escherichia phage SH2026Stx1, Enterobacteria phage mEp043 c-1, and Escherichia phage HK106) in GDM group (r < 0, P < 0.05). Based on gut microbial features and clinical indicators, we constructed a new prediction model using random forest method for GDM with good predictive performance (AUC of 0.893, 95% CI: 0.736 ∼ 0.990). This study is the first to investigate the relationship between the gut virome and GDM as well as the cross-kingdom correlation between gut viruses and bacteria in GDM. Our findings could enhance strategies for preventing and treating GDM from the perspective of gut microbiome, offering valuable insights into its pathogenesis.

Metagenomics analysis of bacterial community structure from wood- and soil-feeding termites: metabolic pathways and functional structures toward the degradation of lignocellulose and recalcitrant compounds.

Some essential information on gut bacterial profiles and their unique contributions to food digestion in wood-feeding termites (WFT) and soil-feeding termites (SFT) is still inadequate. The feeding type of termites is hypothesized to influence their gut bacterial composition and its functionality in degrading lignocellulose or other organic chemicals. This could potentially provide alternative approaches for the degradation of some recalcitrant environmental chemicals. Therefore, metagenomic analysis can be employed to examine the composition and functional profiles of gut bacterial symbionts in WFT and SFT. Based on the metagenomic analysis of the 16S rRNA gene sequences of gut bacterial symbionts in the WFT, Microcerotermes sp., and the SFT, Pericapritermes nitobei, the findings revealed a total of 26 major bacterial phyla, with 18 phyla commonly represented in both termites, albeit in varying abundances. Spirochaetes dominated the bacterial symbionts in Microcerotermes sp. at 55%, followed by Fibrobacters, while Firmicutes dominated the gut bacteria symbionts in P. nitobei at 95%, with Actinobacteria coming in second at 2%. Furthermore, the Shannon and phylogenetic tree diversity indices, as well as the observed operational taxonomic units and Chao 1 richness indices, were all found to be higher in the WFT than in the SFT deduced from the alpha diversity analysis. Based on the principal coordinate analysis, exhibited a significant distance dissimilarity between the gut bacterial symbionts. The results showed that the gut bacterial composition differed significantly between the WFT and SFT. Furthermore, Tax4Fun analysis evaluated bacterial functions, revealing the predominance of carbohydrate metabolism, followed by amino acid metabolism and energy metabolism in both Microcerotermes sp. and P. nitobei termites. The results implicated that bacterial symbionts inhabiting the guts of both termites were actively involved in the degradation of lignocellulose and other recalcitrant compounds.

A review on the interaction between gut microbiome and the brain moleculer and medical microbiology department

Abstract. The gut microbiome, comprised of trillions of microorganisms residing in the gastrointestinal tract, plays a crucial role in maintaining human health and influencing the onset of diseases. This paper delves into the intricate relationship between the gut microbiome and the brain, providing insight into how gut bacteria influence neurological function and mental health. And it examines recent advancements in research on the gut-brain axis, highlighting the mechanisms by which microbiota affect brain chemistry and behavior. In addition, this paper discusses potential therapeutic strategies that target the gut microbiome for treating neurological and psychological disorders. By synthesizing current findings, the research aims to provide a comprehensive understanding of this complex interaction, thereby shedding light on future research directions in neuroscience and mental health.

Propionic Acid Impact on Multiple Sclerosis: Evidence and Challenges.

Accumulating evidence suggests that multiple sclerosis (MS) is an environmentally influenced disorder with contributions from life-time exposure to factors including Epstein-Barr virus infection or shifts in microbiome, diet and lifestyle. One suggested factor is a deficiency in propionic acid, a short-chain fatty acid produced by gut bacteria that may contribute to the disease pathology both in animal models and in human cases of MS. Propionate appears to exert beneficial effects on the immune, peripheral and central nervous systems of people with MS (pwMS), showing immunoregulatory, neuroprotective and neurogenerative effects. These functions are crucial, given that MS is characterized by immune-mediated damage of myelin in the central nervous system. Accordingly, propionate supplementation or a modulated increase in its levels through the microbiome and diet may help counteract the pro-inflammatory state in MS by directly regulating immune system and/or by decreasing permeability of gut barrier and blood-brain barrier. This could potentially improve outcomes when used with immune-modulating therapy. However, while its broad effects are promising, further large clinical trials are necessary to evaluate its efficacy and safety in pwMS and clarify its role as a complementary therapeutic strategy. This review provides a comprehensive analysis of the evidence, challenges and limitations concerning propionic acid supplementation in MS.

Impact of resistant starch type 3 on fecal microbiota and stool frequency in Thai adults with chronic constipation randomized clinical trial

Constipation poses a significant health concern affecting individuals of varying ages and geographic locations worldwide. While the impacts of numerous probiotics on constipation are well-characterized, there has been limited assessment of the potential prebiotic effects of resistant starches. We therefore conducted a randomized, double-blind and placebo-controlled, clinical trial of resistant starch type 3 (RS-3) in Thai adults with self-reported chronic constipation. The effects of these mixed natural starch fibers on beneficial gut bacteria, bowel movements and stool consistency were evaluated after 6- and 12-week periods. Regardless of subject age, consumption of RS-3 compared to placebo resulted in significant improvements in gut health by dramatically increasing levels of beneficial bacteria (Bifidobacterium, Prevotella, Akkermansia and Megamonas) in the gut and relieving constipation. RS-3 consumption was associated with a significantly increased frequency of bowel movements, with subjects reporting these as healthy stools. Our findings provide important insights into the therapeutic advantages of RS-3 for constipation, and propose RS-3 as a feasible alternative strategy for management of constipation.

Visual and Quantitative Analysis of Dietary Fiber-Microbiota Interactions via Metabolic Labeling In Vivo.

Dietary fiber (DF)-based interventions are crucial in establishing a health-promoting gut microbiota. However, directly investigating DFs' in vivo interactions with intestinal bacteria remains challenging due to the lack of suitable tools. Here, we develop an in vivo metabolic labeling-based strategy, which enables not only imaging and identifying the bacteria that bind with specific DF in the intestines, but also quantifying DF's impact on their metabolic status. Four DFs, including galactan, rhamnogalacturonan and two inulins, are fluorescently derivatized and used for in vivo labeling to visually record DFs' interactions with gut bacteria. The subsequent cell-sorting, 16S rDNA sequencing, and fluorescence in situ hybridization identify the taxa that bind each DF. We then select a DF-binding species newly identified herein and verify its DF-catabolizing capability in vitro. Furthermore, we find that the indigenous metabolic status of Gram-positive bacteria, whether inulin-binders or not, is significantly enhanced by the inulin supplement. This trend isn't observed in Gram-negative microbiota, even for the inulin-binders, demonstrating the ability of our methods in differentiating the primary, secondary DF-degraders from cross-feeders, a question that is difficult to answer by using other methods. Our strategy provides a novel chemical biology tool for deciphering the complex DF-bacteria interactions in the gut.

Arenicolide Family Macrolides Provide a New Therapeutic Lead Combating Multidrug‐Resistant Tuberculosis

AbstractThe emergence of multidrug‐resistant (MDR) and extensively drug‐resistant (XDR) strains of Mycobacterium tuberculosis (Mtb) poses a significant threat to health globally. During searching for new chemical entities regulating MDR‐ and XDR‐Mtb, chemical investigation of the black oil beetle gut bacterium Micromonospora sp. GR10 led to the discovery of eight new members of arenicolides along with the identification of arenicolide A (Ar−A, 1), which was a previously reported macrolide with incomplete configuration. Genomic analysis of the bacterial strain GR10 revealed their putative biosynthetic pathway. Quantum mechanics‐based computation, chemical derivatizations, and bioinformatic analysis established the absolute stereochemistry of Ar−A and arenicolides D−K (Ar−D−K, 2–9) completely for the first time. Biological studies of 1–9 revealed their antimicrobial activity against MDR and XDR strains of Mtb. Ar−A had the most potent in vitro antimicrobial efficacy against MDR‐ and XDR‐Mtb. Mechanistically, Ar−A induced ATP depletion and destabilized Mtb cell wall, thereby inhibiting growth. Notably, Ar−A exerted a significant antimicrobial effect against Mtb in macrophages, was effective in the treatment of Mtb infections, and showed a synergistic effect with amikacin (AMK) in a mouse model of MDR‐Mtb lung infection. Collectively, our findings indicate Ar−A to be a promising drug lead for drug‐resistant tuberculosis.

Arenicolide Family Macrolides Provide a New Therapeutic Lead Combating Multidrug-Resistant Tuberculosis.

The emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains of Mycobacterium tuberculosis (Mtb) poses a significant threat to health globally. During searching for new chemical entities regulating MDR- and XDR-Mtb, chemical investigation of the black oil beetle gut bacterium Micromonospora sp. GR10 led to the discovery of eight new members of arenicolides along with the identification of arenicolide A (Ar-A, 1), which was a previously reported macrolide with incomplete configuration. Genomic analysis of the bacterial strain GR10 revealed their putative biosynthetic pathway. Quantum mechanics-based computation, chemical derivatizations, and bioinformatic analysis established the absolute stereochemistry of Ar-A and arenicolides D-K (Ar-D-K, 2-9) completely for the first time. Biological studies of 1-9 revealed their antimicrobial activity against MDR and XDR strains of Mtb. Ar-A had the most potent in vitro antimicrobial efficacy against MDR- and XDR-Mtb. Mechanistically, Ar-A induced ATP depletion and destabilized Mtb cell wall, thereby inhibiting growth. Notably, Ar-A exerted a significant antimicrobial effect against Mtb in macrophages, was effective in the treatment of Mtb infections, and showed a synergistic effect with amikacin (AMK) in a mouse model of MDR-Mtb lung infection. Collectively, our findings indicate Ar-A to be a promising drug lead for drug-resistant tuberculosis.

Appearance of green tea compounds in plasma following acute green tea consumption is modulated by the gut microbiome in mice.

Studies have suggested that phytochemicals in green tea have systemic anti-inflammatory and neuroprotective effects. However, the mechanisms behind these effects are poorly understood, possibly due to differential metabolism of phytochemicals resulting from variation in gut microbiome composition. To unravel this complex relationship, our team utilized a novel combined microbiome analysis and metabolomics approach applied to low complexity microbiome (LCM) and human colonized (HU) gnotobiotic mice treated with an acute dose of powdered matcha green tea. A total of 20 LCM mice received 10 distinct human fecal slurries for an n=2 mice per human gut microbiome; 9 LCM mice remained un-colonized with human slurries throughout the experiment. We performed untargeted metabolomics on green tea and plasma to identify green tea compounds that were found in plasma of LCM and HU mice that had consumed green tea. 16S ribosomal RNA gene sequencing was performed on feces of all mice at study end to assess microbiome composition. We found multiple green tea compounds in plasma associated with microbiome presence and diversity (including acetylagmatine, lactiflorin, and aspartic acid negatively associated with diversity). Additionally, we detected strong associations between bioactive green tea compounds in plasma and specific gut bacteria, including associations between spiramycin and Gemmiger, and between wildforlide and Anaerorhabdus. Additionally, some of the physiologically relevant green tea compounds are likely derived from plant-associated microbes, highlighting the importance of considering foods and food products as meta-organisms. Overall, we describe a novel workflow for discovering relationships between individual food compounds and composition of the gut microbiome.

Biotransformation of Tetrabromobisphenol A and Its Analogs by Selected Gut Bacteria Strains: Implications for Human Health.

Knowledge of the biotransformation of tetrabromobisphenol A (TBBPA) and its related contaminants by human gut microbiota (GM) remains unexplored. Here, TBBPA and its four analogs were incubated with mixed GM strains, and nine rhamnosylated or debrominated transformation products (TPs) were discovered. Remarkably, rhamnosylation was identified as a common and unique microbial transformation pathway for these contaminants, and six of the seven rhamnosylated TPs were reported for the first time. Additionally, a kinetic transformation study also showed a rapid and strong bioaccumulation of TBBPA and TPs by Clostridium manihotivorum. Genomic analysis and phylogenetic studies identified C1.1_02053 as the gene encoding the C. manihotivorum working rhamnosyltransferase (CmRT), showing elevated gene expression with higher TBBPA exposure. Molecular docking identified five critical amino acid residues in CmRT that catalyze TBBPA rhamnosylation, and molecular dynamics simulations further confirmed the stability of the CmRT-TBBPA complex. Dynamic metabolomics analysis showed microbial growth-dependent disturbing effects in C. manihotivorum upon TBBPA exposure, and key metabolic pathways related to rhamnosyltransferase showed changes closely related to the transformation process. These findings provide insights into the unique transformation of environmental contaminants by the GM and highlight the disturbing effects of exogenous chemicals on the GM, as well as the potential impacts on overall human health.

Immunoglobulin-coating patterns reveal altered humoral responses to gut bacteria in pediatric cow milk allergies

BackgroundPediatric cow milk allergies (CMA) can occur in immunoglobulin (Ig) E and non-IgE-mediated forms. Unlike IgE-mediated allergies, the mechanisms of disease pathogenesis in non-IgE-mediated food allergy and an association with microbiome has not been well established. Previous studies have identified the presence of altered humoral responses to gut bacteria in IgE mediated allergies. Here, we analyzed IgA, IgE and IgG responses to gut bacteria in subjects with either IgE or non-IgE mediated CMA to identify relative proportions of Ig-coated bacteria and characterize unique disease specific microbial signatures.MethodsMulti-parametric flow cytometry analysis was used to identify IgA, IgE and IgG responses to gut bacteria in CMA patients. Cell sorting of Ig coated gut bacteria was subsequently performed followed by high throughput 16S rRNA gene sequencing and specific patterns of humoral responses to gut bacteria assessed in each study group.ResultsWe identified significant alterations in IgA and IgG gut bacterial coating patterns in CMA subjects. Proportions of IgA-coated bacteria were decreased in IgE mediated CMA subjects without atopic dermatitis (ALL) and non-IgE mediated CMA subjects (ENP), compared to healthy controls (CON). In comparison, IgG-coated bacteria was significantly elevated in CMA subjects with atopic dermatitis (AD). Alpha and beta diversities displayed significant differences in IgA-, IgE-, and IgG-coated bacteria in AD and ENP groups. Significant differences in bacteria coated by IgA, IgE and IgG were detected at Phyla, Genus and Species levels and associated bacterial dysbiosis in IgE and non-IgE mediated allergies were identified. Linear discriminant analysis (LDA) effect size (LEFse) revealed unique disease associated bacterial signatures, including several pathogenic bacteria namely Bacteroides fragilis, Ruminococcus gnavus, Eubacterium dolichum, Fusobacterium, Clostridium neonatale and Robinsoniella peoriensis. Receiver operating characteristic curve analysis confirmed the efficiency of using the bacterial signatures identified as biomarkers for disease.ConclusionsAltered IgA and IgG responses to gut bacteria were identified in CMA subjects. The disease-specific responses were associated with alterations in bacterial diversity and concomitant dysbiosis of Ig-coated bacteria in IgE-mediated and non-IgE-mediated CMA pediatric subjects. The identification of pathogenic bacteria uniquely associated with different classes of allergic disease indicates a role of these bacteria in driving disease-specific pathological phenotypes.

Allergy Modulation: Exploring the Role of Prebiotics, Probiotics, and Synbiotics in Enhancing Health Outcomes - A Literature Review

This literature review explores the role of prebiotics, probiotics, and synbiotics in the prevention and management of allergic diseases, including eczema, asthma, allergic rhinitis, and food allergies. The review delves into the mechanisms by which these dietary interventions modulate the gut microbiome, influence immune system responses, and enhance the epithelial barrier. While prebiotics promote the growth of beneficial gut bacteria and the production of short-chain fatty acids, probiotics introduce live microorganisms that restore balance in the gut ecosystem. Synbiotics combine both approaches to synergistically improve gut health. Despite the promising potential of these interventions, the evidence remains mixed, with their efficacy varying across different allergic conditions. This review underscores the need for further research to clarify the effectiveness of prebiotics, probiotics, and synbiotics in allergy prevention and management, highlighting the complexities involved in translating these findings into clinical practice.