Regulation of Intestinal Barrier Function by Microbial Metabolites

Bacillus paralicheniformis-mediated gut microbiota promotes M2 macrophage polarization by inhibiting P38 MAPK signaling to alleviate necrotizing enterocolitis and apoptosis in mice

Clostridial necrotizing enterocolitis is a severe gastrointestinal disease induced by Clostridium, strongly associated with intestinal dysbiosis. Fecal microbiota transplantation (FMT) has proven effective in treating gastrointestinal diseases by remodeling intestinal microbial homeostasis. However, it remains unclear whether FMT from donors with beneficial microbiota can improve the recipient's intestinal function more efficiently. This study found that probiotic Bacillus paralicheniformis SN-6-mediated gut microbiota effectively prevent Clostridial necrotizing enteritis and explored the underlying molecular mechanisms. Data demonstrated that SN-6 altered gut microbiota composition, ameliorated Clostridium perfringens-induced intestinal microbiota dysbiosis and metabolic reprogramming, particularly enhancing tryptophan metabolism. This led to a marked reduction in intestinal barrier damage and inflammation. FMT from SN-6-treated mice reduced jejunal inflammation in Clostridium perfringens-infected mice, strengthened jejunal barrier and enriched beneficial bacteria, such as Lactobacillus, Blautia, Akkermansia. Furthermore, 3-indoleacetic acid (IAA), a metabolite enriched by SN-6, activated aryl hydrocarbon receptor (AhR), suppressed the P38 mitogen-activated protein kinase (P38 MAPK) signaling, and drove macrophage polarization from M0 to M2-type, thereby reducing apoptosis and excessive inflammation. This study highlights Bacillus paralicheniformis SN-6 as a key modulator of intestinal immunomodulation via the gut microbiota-IAA-AhR-P38 MAPK axis, offering a potential therapeutic target for preventing and controlling clostridial necrotizing enteritis.

The role of the gut microbiome in the associations between lead exposure and child neurodevelopment

Lead is highly toxic to the developing brain. Given its persistence in the environment, new intervention strategies are needed to mitigate the impacts of lead on child neurodevelopment. The gut microbiome, referring to the bacteria and microorganisms residing in the gastrointestinal system, may be a viable target for intervention. This short review summarizes recent evidence linking the gut-brain axis to child developmental outcomes. We explore how lead-induced effects to the gut microbiome could indirectly affect child neurodevelopment, such that disrupting or offsetting this mediating process could buffer the effects of lead on child developmental outcomes. Unexpected findings with respect to child microbiota diversity and child cognitive and behavioral outcomes as well as lead exposure and adult microbiota diversity are discussed. When possible, we draw connections between observed changes to relative bacterial abundance, proposed bacterial functions, and downstream effects to brain development. We also explore how the gut microbiome might modify the toxicity of lead by impeding the uptake of lead across the gastrointestinal tract or through indirect mechanisms in such ways that the gut microbiome does not fit within a mediating pathway. In this case, promoting the buffering capacity of the gut microbiome may reduce the impacts of lead on child neurodevelopment. The goal of this short review is to bring attention to the potential role of the gut microbiome in the associations between lead exposure and child neurodevelopment with an eye towards intervention.

Regulation of pancreatic β cells by exosomes from different sources

Diabetes is a chronic metabolic disorder with rising global prevalence, particularly in developed and high-income regions. Central to its pathogenesis is the dysfunction of pancreatic β-cells, alongside impaired glucose and lipid metabolism in peripheral insulin-responsive tissues. Exosomes are nano-sized extracellular vesicles essential for intercellular communication and have emerged as pivotal regulators of metabolic homeostasis. Secreted by virtually all cell types, exosomes encapsulate bioactive cargo that reflects their cellular origin and physiological state, thereby exerting diverse functional effects. Recent evidence highlights the role of exosomes derived from the liver, gut, adipose tissue, skeletal muscle, and mesenchymal stem cells in modulating β-cell proliferation, insulin secretion, and survival. In peripheral tissues exosomes also influence insulin sensitivity by regulating glucose and lipid metabolism, ultimately shaping β-cell responses under hyperglycemic conditions. A more comprehensive understanding of exosome-mediated crosstalk between metabolic organs and pancreatic β-cells could pave the way for the development of exosome-based diagnostic tools and therapeutic strategies aimed at improving early detection, prevention, and treatment of the diabetes.

Diet-Induced mechanical stress promotes immune and metabolic alterations in the Drosophila melanogaster digestive tract

A fundamental query in immunology is how cells recognize danger in the tissue milieu. For many years, standpoints were mainly centered around damaged cells or structures of invading pathogens, like lipopolysaccharide, being the initiators of danger signals to activate immunity. Today, rising evidence presents "biophysical signals" as potential regulators of immune cell functions too. This emerging notion of the ability of tissue mechanotransduction to tune the immunological system appears to likewise exist in other body system, among which is the metabolic system, where startling connection between mechanotransduction and enzymesknown to regulate metabolism have been also reported. Being continuously subjected to mechanical forces, and owing to its multifaceted role in not only absorbing and digesting nutrients, but also in supporting important immunological defense strategies as well as metabolic responses, attention has been lately given to organs making up the gastrointestinal (GI) tract, predominantly the intestine, with growing interest in unravelling the impact of mechanotransduction on the intestinal environment is on the rise. As such, we investigated in this study the impact of mechanical stress introduced by ingesting diet containing the indigestible fiber methylcellulose (MC) on gut immune and metabolic activities using the Drosophila melanogaster model organism. Our findings reveal that feeding on MC-containing diet causes consequential alterations in the fly gut environment manifested by enlargement of the midgut diameter, remodeling of the microbiota community, activation of immune responses, differential regulation of the tachykinin (Tk) peptide hormone expression and modulation of lipometabolism. Particularly, we show that feeding on MC-containing diet promotes a marked increase in the relative abundance of Leuconostocaceae/Leuconostoc, microbiota-dependent Reactive Oxygen Species (ROS) production, IMD pathway activation, and IMD-dependent elevation in Tk expression. We also demonstrate that maintaining flies on MC-containing diet for several days leads to a reduction in body weight and in systemic glucose and triacylglycerol levels and modulates lipid droplets accumulation and storage in the gut and fat body. Taken together, these findings provide novel insight into the effect of diet induced-mechanical forces on the intestinal physiology and pathology.

Cutting-edge insights into the mechanistic understanding of plant-derived exosome-like nanoparticles: Implications for intestinal homeostasis

Plant-derived exosome-like nanoparticles (PDELNs) are extracted from plants such as ginger, garlic, broccoli, and others, attracting attention for their therapeutic potential due to their availability and capacity for large-scale production. Their unique physicochemical properties position PDELNs as ideal candidates for targeted gut delivery, improving intestinal health by modulating mucosal immunity, gut microbiota, and intestinal barrier integrity, all essential for maintaining intestinal homeostasis. PDELNs regulate intestinal barrier function through their bioactive components (e.g. microRNAs, lipids, and proteins). These vesicles enhance the expression of tight junction proteins and stimulate mucin production. Additionally, they promote intestinal stem cell proliferation and increase the secretion of antimicrobial peptides. PDELNs also modulate inflammatory cytokine levels and immune cell activity, fostering a balanced immune response. Further, they support the growth of beneficial gut microbiota and their metabolites, while suppressing the proliferation of pathogenic bacteria. This review summarizes recent advancements in understanding the roles of PDELNs in regulating intestinal homeostasis, focusing on their impact on mucosal immunity, intestinal barrier function, and gut microbiota composition, along with underlying molecular mechanisms and therapeutic implications. Overall, PDELNs show promise as a novel approach for treating and preventing intestinal diseases, paving the way for effective gut health interventions.

Gut Microbiota Disorders and Metabolic Syndrome: Tales of a Crosstalk Process

The microbiota in humans consists of trillions of microorganisms that are involved in the regulation of the gastrointestinal tract and immune and metabolic homeostasis. The gut microbiota (GM) has a prominent impact on the pathogenesis of metabolic syndrome (MetS). This process is reciprocal, constituting a crosstalk process between the GM and MetS. In this review, GM directly or indirectly inducing MetS via the host-microbial metabolic axis has been systematically reviewed. Additionally, the specifically altered GM in MetS are detailed in this review. Moreover, short-chain fatty acids (SCFAs), as unique gut microbial metabolites, have a remarkable effect on MetS, and the role of SCFAs in MetS-related diseases is highlighted to supplement the gaps in this area. Finally, the existing therapeutics are outlined, and the superiority and shortcomings of different therapeutic approaches are discussed, in hopes that this review can contribute to the development of potential treatment strategies.

Ginseng polysaccharides ameliorate colorectal tumorigenesis through Lachnospiraceae-mediated immune modulation

Probiotics and their metabolites play a critical role in immunotherapy for colorectal cancer (CRC) and intestinal damage. Identifying specific probiotics from natural products and elucidating the underlying mechanisms represent promising strategies for CRC research. This study investigated the structural characterization and therapeutic potential of ginseng polysaccharides (GPS) in inhibiting tumor growth. The results showed that the molecular weight of GPS was 2425.512 kDa, which was mainly composed of Man, GluA, Gal, Glc, Xyl, and Ara contained in its structure. GPS (100, 200, and 400 mg/kg) significantly ameliorates colorectal tumorigenesis in AOM/DSS-induced and MC38-induced CRC models. 16S rRNA shows that GPS supplementation significantly increased the abundance of Lachnospiraceae compared to the model group. Mechanistically, GPS supplementation promoted the proliferation of beneficial Lachnospiraceae bacterium (L.B.), leading to increased short-chain fatty acids (SCFAs) production. The effective anti-CRC effects of key probiotics were further substantiated by their ability to inhibit myeloid-derived suppressor cells (MDSCs) and enhance the infiltration and activation of CD8+ T cells. These findings highlight the pivotal role of GPS-induced alterations in the potential probiotics L.B. production in CRC suppression, emphasizing the potential of GPS in immune regulation for microbiome-targeted cancer therapies.

Gut microbiota and their influence in brain cancer milieu

Microbial communities are not simply remnants of the past but dynamic entities that continuously evolve under the selective pressures of nature, reflecting the intricate and adaptive processes of evolution. The microbiota residing in the various regions of the human body has numerous roles in different physiological processes such as nutrition, metabolism, immune regulation, etc. In the zeal of achieving empirical insights into the ambit of the gut microbiome, the research over the years led to the revelation of reciprocal interaction between the gut microbiome and the cognitive functioning of the human body. Dysbiosis in the gut microbial composition disturbs the homeostatic cognitive functioning of the human body. This dysbiosis has been associated with various chronic diseases, including brain cancer, such as glioma, glioblastoma, etc. This review explores the mechanistic role of dysbiosis-mediated progression of brain cancers and their subtypes. Moreover, it demonstrates the regulatory role of microbial metabolites produced by the gut microbiota, such as short-chain fatty acids, amino acids, lipids, etc., in the tumour progression. Further, we also provide valuable insights into the microbiota mediating the efficiency of therapeutic regimens, thereby leveraging gut microbiota as potential biomarkers and targets for improved treatment outcomes.

Apigenin Alleviates Intestinal Ischemia/Reperfusion Injury via Upregulating Nrf2-Mediated Tight Junction Integrity

Epithelial barrier dysfunction, critically involved in intestinal ischemia/reperfusion (I/R) injury, is significantly regulated by Nrf2-mediated oxidative stress. Apigenin, a flavonoid commonly found in fruits and vegetables with diverse biological properties, has an unclear impact on intestinal I/R injury. We hypothesize that apigenin improves intestinal barrier dysfunction by activating Nrf2 signaling. Thirty rats were randomly divided into five groups to establish an I/R model using superior mesenteric artery occlusion. Hypoxia and re-oxygenation (H/R) model was developed utilizing Caco-2 and IEC-6 cells, which were exposed to hypoxic conditions followed by re-oxygenation. Apigenin protected against intestinal mucosal damage by suppressing inflammatory cytokines release (TNF-α, IL-1β, IL-6, MPO, p < 0.01), ameliorating oxidative stress (MDA, SOD, GSH, GSH-Px, p < 0.01), and improving barrier dysfunction (DAO and TEER, p < 0.01) both in vivo and in vitro, without causing significant changes in the corresponding normal controls (p > 0.05). Apigenin up-regulated the protein expression of Nrf2, HO-1, and tight junction (TJ) proteins (p < 0.01). Furthermore, the knockdown of Nrf2 significantly abrogated apigenin-enhanced the TJ expression. Apigenin pretreatment alleviates intestinal I/R-induced barrier damage through Nrf2 activation and TJ upregulation, offering new strategies for preventing or treating I/R-associated intestinal diseases.

Small amounts of misassembly can have disproportionate effects on pangenome-based metagenomic analyses

Individual genes from microbiomes can drive host-level phenotypes. To help identify such candidate genes, several recent tools estimate microbial gene copy numbers directly from metagenomes. These tools rely on alignments to pangenomes, which, in turn, are derived from the set of all individual genomes from one species. While large-scale metagenomic assembly efforts have made pangenome estimates more complete, mixed communities can also introduce contamination into assemblies, and it is unknown how robust pangenome-based metagenomic analyses are to these errors. To gain insight into this problem, we re-analyzed a case-control study of the gut microbiome in cirrhosis, focusing on commensal Clostridia previously implicated in this disease. We tested for differentially prevalent genes in the Lachnospiraceae and then investigated which were likely to be contaminants using sequence similarity searches. Out of 86 differentially prevalent genes, we found that 33 (38%) were probably contaminants originating in taxa such as Veillonella and Haemophilus, unrelated genera that were independently correlated with disease status. Our results demonstrate that even small amounts of contamination in metagenome assemblies, below typical quality thresholds, can threaten to overwhelm gene-level metagenomic analyses. However, we also show that such contaminants can be accurately identified using a method based on gene-to-species correlation. After removing these contaminants, we observe that several flagellar motility gene clusters in the Lachnospira eligens pangenome are associated with cirrhosis status. We have integrated our analyses into an analysis and visualization pipeline, PanSweep, that can automatically identify cases where pangenome contamination may bias the results of gene-resolved analyses.IMPORTANCEMetagenome-assembled genomes, or MAGs, can be constructed without pure cultures of microbes. Large-scale efforts to build MAGs have yielded more complete pangenomes (i.e., sets of all genes found in one species). Pangenomes allow us to measure strain variation in gene content, which can strongly affect phenotype. However, because MAGs come from mixed communities, they can contaminate pangenomes with unrelated DNA; how much this impacts downstream analyses has not been studied. Using a metagenomic study of gut microbes in cirrhosis as our test case, we investigate how contamination affects analyses of microbial gene content. Surprisingly, even small, typical amounts of MAG contamination (<5%) result in disproportionately high levels of false positive associations (38%). Fortunately, we show that most contaminants can be automatically flagged and provide a simple method for doing so. Furthermore, applying this method reveals a new association between cirrhosis and gut microbial motility.

Identifying metabolic biomarkers and pathways in pulpitis: a metabolomic study using ultra-high-performance liquid chromatography/orbitrap mass spectrometry

BACKGROUND

Pulpitis, which is often triggered by caries and trauma, is a significant clinical challenge due to its prevalence. This research aims to uncover potential metabolic biomarkers for pulpitis and map out the implicated metabolic pathways, thereby laying a foundation for enhanced diagnostic and preventive strategies.

METHODOLOGY

We analyzed pulp samples from 12 participants (six who had pulpitis and six who had healthy teeth) using serum metabolomics via ultra-high-performance liquid chromatography coupled with Orbitrap mass spectrometry. Important biomarkers were pinpointed via multivariate analysis and orthogonal partial least squares discriminant analysis. Additionally, correlation and biomarker pathway enrichment analyses were conducted to explore the relations between differentially expressed biomarkers and their associated biological pathways. Specific metabolites of interest were further examined via alkaline phosphatase (ALP) staining, Alizarin Red staining, and RT-qPCR analysis.

RESULTS

We identified 22 significant biomarkers (13 increased, nine decreased) related to 18 metabolic pathways in pulpitis cases. Key biomarkers included ascorbic acid, inosine, allopurinol riboside, and L-asparagine, in which ascorbic acid and inosine showed the most substantial downregulation and strongest association with pulpitis. Notably, aminoacyl-tRNA biosynthesis and retrograde endocannabinoid signaling pathways were closely linked with pulpitis. Ascorbic acid enhanced the osteogenic differentiation, calcium deposition, as well as the expression of osteogenic genes of human dental pulp stem cells (DPSCs).Conclusions: The identified biomarkers and metabolic pathways offer insights into the pathogenesis of pulpitis and have potential applications in developing preventive treatments.

Improvement of the inflammation-damaged intestinal barrier and modulation of the gut microbiota in ulcerative colitis after FMT in the SHIME® model

BACKGROUND

Fecal microbiota transplantation (FMT) seems to be a promising approach in ulcerative colitis (UC) management with the aim of repopulating a patient's dysbiotic microbiota with beneficial bacteria and restore its metabolic activity to its healthy characteristics. Metabolites present after FMT may improve the function and integrity of the intestinal barrier, reduce inflammation, and thus induce remission in an UC patient. In this study we evaluated whether the Simulator of the Human Intestinal Microbial Ecosystem (SHIME®) model may be a suitable non-invasive alternative for studying and modifying the dysbiotic microbiota in UC by FMT application.

METHODS

SHIME® model was used to investigate microbial and metabolic changes in the gut microbiota of UC patient induced by FMT application. FMT-modified metabolites from SHIME® were applied to an in vitro model of the intestinal barrier (differentiated Caco-2 and HT-29-MTX-E12 cell lines) compromised by pro-inflammatory cytokines to study the effect of FMT on the intestinal barrier.

RESULTS

Qualitative and quantitative microbial analyses showed that FMT increased the diversity and variability of the microbiota in UC patient associated with a significant increase in total bacteria, Bacteroidota and Lactobacillus, as well as an increase in butyrate levels. In addition, an increase in the relative abundance of some important species such as Faecalibacterium prausnitzii and Bifidobacterium longum was observed, and there was also an enrichment of the microbiota with new species such as Blautia obeum, Roseburia faecis, Bifidobacterium adolescentis, Fusicatenibacter saccharivorans and Eubacterium rectale. Furthermore, microbial metabolites modulated by FMT from the SHIME® model prevented intestinal barrier damage and inhibited interleukin 8 (IL-8) and monocyte chemoattractant protein 1 (MCP-1) secretion when cell barriers were pretreated with FMT medium for 24 h. In summary, this study confirmed that a single dose of FMT beneficially modulated the composition and metabolic activity of the UC microbiota in the SHIME® model.

CONCLUSIONS

FMT favorably modulates the gut microbiota of UC patient cultured in the SHIME® model. FMT-modulated SHIME-derived microbial metabolites improve intact and inflamed intestinal barrier properties in vitro. Repeated applications are necessary to maintain the beneficial effect of FMT in SHIME® model.

Bioactive Polysaccharides from Hericium erinaceus: Extraction, Structure, Bioactivities, and Applications

Hericium erinaceus, an edible fungus belonging to the family Odontaceae, is predominantly found in Western Europe, North America, and East Asia. In China, it primarily thrives in the mountainous and forested regions in the northeast, north, and southwest. Historically, Hericium erinaceus has served as a medicinal and nutritional entity. Its mycelia and fruiting bodies are the products of its vegetative growth stage and reproductive growth stage, respectively. The principal active components are different Hericium erinaceus polysaccharides (HEPs), which are a group of polysaccharides primarily composed of galactose, glucose, and a small amount of mannose and fucose. An extremely small number of HEPs contain fructose, glucuronic acid, xylose, arabinose, and other components. The common extraction method employed is water extraction followed by alcohol precipitation. HEPs exhibit a diverse array of biological activities, including immune enhancement, anti-tumor effects, anti-inflammatory properties, antioxidant capabilities, and antiviral functions. This paper provides a comprehensive review of recent advancements in the extraction, separation, purification, structural analysis, biological activity, and toxicity assessments of HEPs. Additionally, it discusses the opportunities and challenges associated with scientific research and practical applications in this field.

Studies on the changes in rectal permeability and intestinal microbiota with developmental age in young rats

Introduction

The gut contains a diverse array of commensal microorganisms, forming a vital biological barrier within the intestine that contributes to the overall intestinal mucosal barrier. However, research on the rectal barrier during early development remains limited. This study aims to investigate the relationship between intestinal microbiota and rectal barrier function in young rats.

Methods

We evaluated the rectal barrier structure and function in rats at 2-, 4-, and 10-week-old. Methodology included histological analysis, Muc2 expression quantification, immunofluorescence localization of tight junction proteins (ZO-1, Occludin, Claudins), blood glucose monitoring after rectal insulin administration, and 16S rDNA sequencing of rectal microbiota. Spearman correlation analysis was used to explore mechanisms linking age-dependent changes in rectal permeability to microbiota dynamics.

Results

Physiological rectal permeability was significantly higher in 2-week-old rats compared to 4- and 10-week-old rats (p < 0.01), although systemic biomarkers (LPS, D-LA, and LBP) showed no significant differences. The rectal microbiota exhibited marked age-dependent shifts in composition, α/β-diversity, and metabolic pathways, with increased abundance of beneficial taxa (e.g., Muribaculaceae, Akkermansia) in older rats. Correlation analysis revealed strong associations between reduced permeability, elevated Occludin expression, and microbiota maturation (R = 0.65, p < 0.001).

Conclusion

This study demonstrates that age-dependent maturation of the rectal barrier is closely linked to microbiota composition and tight junction protein expression, providing insights into developmental mechanisms and potential strategies for pediatric rectal drug delivery.

Bacteroides thetaiotaomicron: A symbiotic ally against diarrhea along with modulation of gut microbial ecological networks via tryptophan metabolism and AHR-Nrf2 signaling

INTRODUCTION

Bacteroides is a crucial mucosal symbiotic bacterium in mammals, with Bacteroides thetaiotaomicron (B. thetaiotaomicron) being particularly noteworthy as a glyco-specialist due to its significant nutritional impact. However, the potential effects of B. thetaiotaomicron on host health remain underexplored.

OBJECTIVES

This study aimed to investigate the patterns of microbial community changes and the molecular mechanisms mediated by microbial metabolites in alleviating piglet diarrhea through B. thetaiotaomicron intervention.

METHODS

Cold stress was induced in piglets to trigger stress-induced diarrhea. The control group and B group were administered a blank medium and 1 × 108 CFU of B. thetaiotaomicron, respectively, on days 1, 3, and 5. The diarrhea rate and growth performance of the piglets were recorded during the experimental period. Based on 16S rRNA gene amplicon sequencing, microbial ecological networks analysis, and metabolomics analysis, the composition and changes of the colonic microbiota and metabolites were analyzed. The antibacterial capacity and anti-inflammatory molecular mechanisms of B. thetaiotaomicron metabolites were analyzed through in vitro antibacterial assays and inflammatory cell models.

RESULTS

B. thetaiotaomicron administration alleviated diarrhea and improved the growth performance of piglets. It modulated the composition and interactions of the intestinal microbiota, with microbial metabolites primarily enriched in the tryptophan metabolism pathway-especially indole and its derivatives, which were closely associated with host phenotypes. In vitro co-culture experiments showed that B. thetaiotaomicron metabolites inhibited the growth of pathogenic bacteria. Further experiments demonstrated that these metabolites, including indole, enhanced epithelial barrier function and attenuated TNF-α-induced inflammation and apoptosis in Caco-2 cells, highlighting the involvement of the AHR-Nrf2 signaling pathway in mediating these protective effects.

CONCLUSION

In conclusion, this study offers a theoretical framework for understanding the role of the symbiotic bacterium B. thetaiotaomicron in the gut microbiota ecosystem during diarrhea and its interactions with the host's intestinal tract.

Matrix Dynamics and Microbiome Crosstalk: Matrix Metalloproteinases as Key Players in Disease and Therapy

Matrix metalloproteinases (MMPs) are key enzymes involved in extracellular matrix (ECM) remodeling, regulating a wide range of cellular and immune processes in both homeostatic and pathological conditions. Host-microbiota interactions play a critical role in maintaining ECM balance; however, during dysbiosis, this regulation is disrupted, leading to compromised barrier integrity, pathogen translocation into circulation, and the development of systemic diseases and cancer. This review highlights the bidirectional relationship between MMP expression/activity and microbiota dysbiosis, emphasizing tissue-specific alterations in MMP activity that contribute to disease progression. In addition, it integrates interdisciplinary evidence to illustrate the MMP-dependent mechanisms underlying various pathologies associated with oral and gut microbiome dysbiosis, including long-range effects through the gut-skin and gut-brain axes. Thus, this review introduces the emerging field of MatrixBiome, which explores the complex interactions between the ECM, microbiota, and host tissues. Finally, it also outlines therapeutic strategies to modulate MMP levels, either indirectly through microbiome-targeted approaches (e.g., prebiotics, probiotics, and postbiotics) or directly using MMP inhibitors, offering promising avenues for future clinical interventions.

TASTY trial: protocol for a study on the triad of nutrition, intestinal microbiota and rheumatoid arthritis

BACKGROUND

The gut microbiota has been implicated in the onset and progression of Rheumatoid Arthritis (RA). It has been proposed that gut dysbiosis impairs gut barrier function, leading to alterations in mucosal integrity and immunity. This disruption allows bacterial translocation, contributing to the perpetuation of the inflammatory process. Since diet is recognised as a key environmental factor influencing the gut microbiota, nutritional interventions targeting RA activity are currently being explored. This study aims to investigate whether a dietary intervention based on a typical Mediterranean Diet enriched with fermented foods (MedDiet +) can impact the gut microbiota, intestinal permeability, and RA-related outcomes.

METHODS

One hundred RA patients are being recruited at Unidade Local de Saúde (ULS) Santa Maria in Lisbon, Portugal, and randomly assigned to either the intervention (MedDiet +) or the control group. The 12-week nutritional intervention includes a personalised dietary plan following the MedDiet + pattern, along with educational resources, food basket deliveries, and clinical culinary workshops, all developed and monitored weekly by registered dietitians. The control group receives standardised general healthy diet recommendations at baseline. The intervention's effects will be assessed by evaluating disease activity, functional status, quality of life, intestinal permeability, endotoxemia, inflammatory biomarkers, intestinal and oral microbiota, serum proteomics, and serum glycome profile characterisation.

DISCUSSION

We anticipate obtaining integrative insights into the interplay between diet, the gut, and RA, while also exploring the underlying mechanisms driving these changes. This study, conducted by a multidisciplinary research team of registered dietitians, rheumatologists, biologists, and immunologists, aims to bridge the current gap between nutrition-related knowledge and RA.

TRIAL REGISTRATION

Registered in ClinicalTrials.gov (NCT06758817; date of registry: January 6th 2025).

Feeding the future: A new potential nutritional impact of Lactiplantibacillus plantarum and its promising interventions in future for poultry industry

The increasing demand for sustainable and efficient chicken production has intensified the interest in functional feed additives such as probiotics. Lactiplantibacillus plantarum (formerly known as Lactobacillus plantarum) is an important probiotic bacterium that has become an essential component in poultry nutrition owing to its diverse advantages. This bacterium improves gut health by regulating the intestinal microbiota, increasing food absorption, and strengthening the immune system. It also alleviates the detrimental impacts of pathogenic bacteria, thereby reducing the reliance on antibiotics and promoting antibiotic-free poultry production. Additionally, Lactobacillus plantarum enhances growth performance, feed conversion efficiency, and total flock productivity. Adding Lactobacillus plantarum to chicken feed helps the gut microbiota by encouraging good bacterial communities (e.g., Eubacterium, Faecalibacterium, Ligilactobacillus, Limosilactobacillus, Blautia and Clostridium). This leads to increased growth in chickens and helps maintain the balance of their gut flora. Lactobacillus plantarum has been extensively investigated as a potential feed additive to replace in-feed antibiotics. Published literature have revealed that a dietary additive of Lactobacillus plantarum improved the health and growth of broilers by improving the balance of bacteria and the metabolism of nutrients in the gut. This study explores the incorporation of Lactobacillus plantarum into poultry diets and its importance in sustainable and healthy poultry production. This study will encourage poultry scientists to investigate further before encapsulation. Innovations in Lactiplantibacillus plantarum, including its intestine colonization methods and novel strategies to improve its colonization, have the potential to transform the industry. Rapid development of tools and techniques (microencapsulated, nanotechnology, metagenomics, and transcriptome for L. plantarum) could help cover research and application shortages.

Anti-Inflammatory Effect of Dendrobium officinale Extract on High-Fat Diet-Induced Obesity in Rats: Involvement of Gut Microbiota, Liver Transcriptomics, and NF-κB/IκB Pathway

The growing prevalence of obesity is being increasingly acknowledged as a major public health issue. This mainly stems from the excessive intake of dietary fats. Dendrobium officinale (DO), recognized as an herb with dual roles of food and medicine, is renowned for its diverse health-promoting effects. Nevertheless, the specifics of its antiobesity and anti-inflammatory properties and the underlying mechanisms are still obscure. The present study shows that treatment with Dendrobium officinale extract (DOE) alleviates obesity, liver steatosis, inflammation, and oxidative stress in rats that are obese due to a high-fat diet (HFD). Firstly, with respect to HFD obese rats, higher doses of DOE significantly reduced TG, TC, LDL-C, blood glucose, and liver AST and ALT, along with lipid droplets. Meanwhile, DOE supplementation significantly reduced oxidative stress induced by ROS and MDA and increased the levels of GSH-Px and SOD in liver tissues. Furthermore, integrated analysis of transcriptomic and microbiomic data revealed that DOE modulated inflammatory responses through the NF-κB/IκB pathway. This regulatory mechanism was evidenced by corresponding changes in the protein expression levels of both NF-κB and IκB. Additionally, DOE was found to modulate gut microbiota composition in obese rats, specifically reducing the relative abundance of Bilophila while increasing beneficial bacterial populations, particularly the genera Akkermansia and Roseburia. These findings suggest that DOE may help retain the homeostasis of the gut microbiota and improve metabolic health by regulating inflammation in the liver and intestine, thereby providing protection against obesity and related metabolic syndromes. Our study demonstrates that DOE, as a natural botanical extract, can effectively facilitate the prevention or treatment of metabolic syndrome through precision dietary interventions.

Restorative Effects of Short-Chain Fatty Acids on Corneal Homeostasis Disrupted by Antibiotic-Induced Gut Dysbiosis

The gut microbiota plays a crucial regulatory role in various physiological processes, yet its impact on corneal homeostasis remains insufficiently understood. Here, the effects of antibiotic-induced gut dysbiosis (AIGD) and germ-free conditions were investigated on circadian gene expression, barrier integrity, nerve density, and immune cell activity in the corneas of mice. Both AIGD and germ-free conditions significantly disrupted the overall transcriptomic profile and circadian transcriptomic oscillations in the cornea, as indicated by RNA sequencing. These molecular disturbances were accompanied by a reduction in corneal epithelial thickness, nerve density, corneal sensitivity, and compromised barrier function. Notably, supplementation with short-chain fatty acids (SCFAs) significantly restored corneal integrity in AIGD mice. Further single-cell sequencing revealed that SCFA receptors G-protein-coupled receptor 109A (Hcar2), olfactory receptor 78 (Olfr78), and G-protein-coupled receptor 43 (Ffar2) are expressed in corneal epithelial basal cells, embryonically derived macrophages, perivascular cells, and γδ T cells, respectively. In conclusion, this study demonstrated that the gut microbiota plays a critical role in corneal physiology by regulating circadian gene expression and maintaining barrier function. These findings enhance our understanding of the gut-eye axis, highlighting the cornea as a target for microbiota-derived metabolic signals and underlining the potential therapeutic value of SCFAs in treating corneal dysfunction.

A Bacillus subtilis xylanase improves nutrient digestibility, intestinal health and growth performance of broiler chickens undergoing an intestinal challenge

The objective of this experiment was to evaluate the effects of a Bacillus subtilis xylanase on nutrient digestibility, intestinal health, and growth performance of broiler chickens undergoing an intestinal challenge. Nine hundred one-day-old Cobb 500 male chicks were randomly distributed into three dietary treatments with 10 replicates (30 birds/pen) until 42 d. Treatments were: Control (CT) diet, energy reduction (ER) diet, and the ER diet supplemented with B. subtilis endo 1,4-β-xylanase at 100 g/t (ER+xylanase). The ER diets had metabolizable energy reductions as per manufacturer guidelines: 80, 82, 87, and 92 kcal/kg for pre-starter, starter, grower, and finisher, respectively. All birds were challenged with Eimeria spp. on d 1 and Clostridium perfringens on d 12-14. Feed intake, body weight gain (BWG), and feed conversion ratio (FCR) were evaluated weekly. On d 17, the intestinal permeability was determined using fluorescein isothiocyanate-dextran (FITC-d) as marker. On d 21, I See Inside (ISI) methodology assessed intestinal alterations. On days 21 and 42, nutrient digestibility and cecal short-chain fatty acids (SCFA) concentrations were calculated. Data underwent ANOVA or Kruskal-Wallis tests, followed by Fisher or Dunn tests, respectively. From 0 to 42 d, broilers fed the ER+xylanase diet had greater (P = 0.046) BWG than birds fed the ER diet, while FCR showed improvements in CT and ER+xylanase diets. Broilers fed the ER+xylanase diet had improved intestinal integrity with the lowest (P = 0.017) serum FITC-d concentration and highest (P = 0.057) Mucin-2. Pancreas ISI scores were worsened (P = 0.034) in CT and ER diets compared to ER+xylanase diet. Ileal digestibility of DM and energy, and SCFA were greater (P ≤ 0.006) in broilers fed the ER+xylanase diet compared to ER diet. In conclusion, the B. subtilis xylanase supplementation improved nutrient digestibility, enhanced intestinal barrier integrity and increased SCFA concentrations which improved growth performance in broilers undergoing an intestinal challenge. Results indicated that this xylanase was able to compensate the energy reduction in corn-soy diets fed to broiler chickens.

Recent Insights into the Evolving Role of the Gut Microbiome in Critical Care

This review explores the evolving understanding of gut microbiota's role in critical illness, focusing on how acute illness and exposures in intensive care unit (ICU) environment negatively impact the gut microbiota and the implications of these changes on host responses in critically-ill patients. Focusing on recent findings from clinical and preclinical studies, we discuss the effects of inflammation, enteral nutrient deprivation, and antibiotics on gut microbial dynamics. This review aims to enhance comprehension of microbial dynamics in the ICU and their implications for clinical outcomes and therapeutic strategies.

Dynamic alterations of depressive-like behaviors, gut microbiome, and fecal metabolome in social defeat stress mice

Gut microbiome is implicated in the onset and progression of major depressive disorder (MDD), but the dynamic alterations of depressive symptoms, gut microbiome, and fecal metabolome across different stages of stress exposure remain unclear. Here, we modified the chronic social defeat stress (CSDS) model to evaluate mice subjected to social defeat stress for 1, 4, 7, and 10 days. Behavioral tests, 16S rRNA, metagenomics, and fecal metabolomics were conducted to investigate the impact of stress exposure on behaviors, gut microbiota and fecal metabolites. We observed that depressive-like behaviors, such as anhedonia and social avoidance, worsened significantly as stress exposure increased. The microbial composition, function, and fecal metabolites exhibited distinct separations across the different social defeat stress groups. Mediation analysis identified key bacteria, such as Lachnospiraceae_UCG-001 and Bacteroidetes, and fecal metabolites like valeric acid and N-acetylaspartate. In our clinical depression cohort, we confirmed that fecal valeric acid levels, were significantly lower in depressive-like mice and MDD patients, correlating closely with stress exposure and anhedonia in mice. Further analysis of serum and brain metabolites in mice revealed sustained changes of N-acetylaspartate abundance in fecal, serum, and cortical samples following increasing stress exposure. Together, this study elucidated the characteristics of depressive-like behaviors, gut microbiome, and fecal metabolome across various social defeat stress exposure, and identified key bacteria and fecal metabolites potentially involved in modulating social defeat stress response and depressive-like behaviors, providing new insights into the pathogenesis and intervention of depression.

Supplementation with the Probiotic Strains Bifidobacterium longum and Lactiplantibacillus rhamnosus Alleviates Glucose Intolerance by Restoring the IL-22 Response and Pancreatic Beta Cell Dysfunction in Type 2 Diabetic Mice

Type 2 diabetes (T2D) is known as adult-onset diabetes, but recently, T2D has increased in the number of younger people, becoming a major clinical burden in human society. The objective of this study was to determine the effects of Bifidobacterium and Lactiplantibacillus strains derived from the feces of 20 healthy humans on T2D development and to understand the mechanism underlying any positive effects of probiotics. We found that Bifidobacterium longum NBM7-1 (Chong Kun Dang strain 1; CKD1) and Lactiplantibacillus rhamnosus NBM17-4 (Chong Kun Dang strain 2; CKD2) isolated from the feces of healthy Korean adults (n = 20) have anti-diabetic effects based on the insulin sensitivity. During the oral gavage for 8 weeks, T2D mice were supplemented with anti-diabetic drugs (1.0-10 mg/kg body weight) to four positive and negative control groups or four probiotics (200 uL; 1 × 109 CFU/mL) to groups separately or combined to the four treatment groups (n = 6 per group). While acknowledging the relatively small sample size, this study provides valuable insights into the potential benefits of B. longum NBM7-1 and L. rhamnosus NBM17-4 in mitigating T2D development. The animal gene expression was assessed using a qRT-PCR, and metabolic parameters were assessed using an ELISA assay. We demonstrated that B. longum NBM7-1 in the CKD1 group and L. rhamnosus NBM17-4 in the CKD2 group alleviate T2D development through the upregulation of IL-22, which enhances insulin sensitivity and pancreatic functions while reducing liver steatosis. These findings suggest that B. longum NBM7-1 and L. rhamnosus NBM17-4 could be the candidate probiotics for the therapeutic treatments of T2D patients as well as the prevention of type 2 diabetes.

Fucoidan from Apostichopus japonicus enhances intestinal barrier function and promotes intestinal immunity via regulating the gut microbiota and tryptophan metabolism

Apostichopus japonicus is one of the most popular types of sea cucumber among consumers in Southeast Asia. Fucoidan from Apostichopus japonicus (Aj-FUC) has attracted considerable attention because of its immunomodulatory activities. Aj-FUC is indigestible in the human upper gastrointestinal tract but can be utilized by the gut microbiota. Thus, we suspect that Aj-FUC interacts with the gut to enhance immunefunction. This study showed that after a three-week intervention with Aj-FUC (100 mg/kg/d), the gut microbiota in mice developed a new homeostasis. Subsequently, in the condition of intestinal flora homeostasis, the effects of Aj-FUC on intestinal health in normal mice and the prevention of intestinal mucosal damage in cyclophosphamide-induced mice were investigated. Aj-FUC preserved intestinal structural integrity, increased the number of goblet cells, upregulated the expression of ZO-1 and Occludin, stimulated the secretion of sIgA and IgA, and maintained the Th1/Th2 balance. Importantly, beneficial bacteria were enriched, and tryptophan metabolism-related metabolites such as 5-hydroxyindole-3-acetic acid, and indole-3-lactic acid were upregulated following Aj-FUC administration. In summary, a three-week Aj-FUC intervention could result in the formation of a new homeostasis in intestinal flora, while the effect of Aj-FUC on intestinal immunity was related to the regulation of tryptophan metabolism by gut microbiota.

Edgeworthia gardneri (Wall.) Meisn protects against HFD-induced murine atherosclerosis through improving gut microbiota-mediated intestinal barrier integrity

BACKGROUND

Gut microbiota plays a crucial role in the development and progression of atherosclerosis. Edgeworthia gardneri (Wall.) Meisn, a member of the Thymelaeaceae family and the Edgeworthia genus, has been previously shown in our studies to attenuate atherogenesis when administered orally as an ethanolic extract (EEEG). However, the interaction between EEEG and gut microbiota, and the mechanism by which gut microbiota exerts anti-atherosclerotic effects, remains unclear.

AIMS

This study aims to determine whether the anti-atherosclerotic properties of EEEG are associated with gut microbiota remodeling.

METHOD

Atherosclerosis was induced in ApoE-/- mice using a high-fat diet (HFD). The mice were treated with EEEG or Lactobacillus plantarum for 16 weeks. The composition of gut microbiota was analyzed through 16S rDNA sequencing. To assess whether the anti-atherosclerotic effects of EEEG depend on the gut microbiota, HFD-fed mice were treated with a cocktail of antibiotics or underwent fecal microbiota transplantation (FMT). Simultaneously, plaque areas in the aortic roots and whole aortas of apolipoprotein E deficient (ApoE-/-) mice were evaluated using oil red O staining and hematoxylin-eosin staining. Serum levels of LPS, fluorescein isothiocyanate-dextran, and expression levels of tight junction proteins were measured to identify the effects of EEEG on gut barrier dysfunction in HFD-fed ApoE-/- mice.

RESULTS

The results revealed that EEEG treatment significantly reduced atherosclerotic lesions by ameliorating lipid accumulation and preserving gut barrier integrity. The protective effects were abrogated by antibiotics administration, concomitant with an increase in gut barrier permeability by decreasing expression of tight junction proteins. The microbial analysis indicated an augmented abundance of Lactobacillus, Turicibacter, Faecalibacterium, Akkermansia, and Desulfovibrio following EEEG treatment. Meanwhile, transplantation of fecal microbiota from EEEG-treated mice exerted the anti-atherosclerotic effect in the high-fat diet (HFD)-fed ApoE-/- recipient mice, accompanied by improvement of gut barrier integrity through upregulation of tight junction protein expression. Furthermore, exogenous supplementation of Lactobacillus plantarum mitigated AS in ApoE-/- mice and improved the gut epithelial barrier function by increasing the expression level of Zo-1.

CONCLUSION

These results suggest that the anti-atherosclerotic efficacy of EEEG is attributed to the preservation of gut barrier integrity mediated by gut microbiota. EEEG and its enriched Lactobacillus plantarum may be promising adjuncts for AS management.

IMPORTANCE

Atherosclerosis (AS) is the primary pathological basis of cardiovascular disease (CVD). The gut microbiota is known to play an important role in the development and progression of atherosclerosis. In the clinical management of AS, pharmacological classes such as antioxidants, lipid-lowering drugs, and antiplatelet agents are commonly utilized. Despite their ability to decelerate the progression of AS, complications and adverse reactions still limit their application. Edgeworthia gardneri (Wall.) Meisn, a member of the Thymelaeaceae family and Edgeworthia Meisn genus, has been shown in previous studies to attenuate atherogenesis when orally administered as an ethanolic extract (EEEG). However, the interaction between EEEG and the gut microbiota, as well as the mechanism by which the gut microbiota exerts its anti-atherosclerotic effects, remain unclear. The significance of our research lies in identifying the mechanism behind the anti-atherosclerotic effect of Edgeworthia gardneri. The expected results will provide an important scientific basis for the clinical development and application of Edgeworthia gardneri in the prevention and treatment of AS.

Ellagic Acid and Gut Microbiota: Interactions, and Implications for Health

Ellagic acid (EA), a widely distributed natural polyphenolic acid existing in many kinds of plant-based foods, undergoes complex physical and chemical transformations during digestion and biotransformation. Particularly, EA is metabolized by gut microbiota and transformed into urolithins in the colon. These metabolites exhibit enhanced bioavailability and bioactivity. This review explores the intricate interactions between EA and gut microbiota, emphasizing their implications for human health. We discuss the role of gut microbiota in EA metabolism, resulting in distinct metabolic phenotypes associated with varying urolithin production profiles. EA and its gut-derived metabolites, urolithins, have been reported to have the potential to modulate the microbial community composition and function of gut microbiota, promoting beneficial bacteria while reducing harmful ones. Furthermore, EA and urolithins exhibit a spectrum of beneficial biological activities, including antioxidant, anti-inflammatory, and anticancer properties, along with enhancements to intestinal barrier function and modulatory effects on metabolic and cardiovascular systems, through molecular mechanisms such as activating Nrf2 and inhibiting NF-κB pathways. The review highlights and compares the potential of EA and its gut microbial metabolites in the prevention and treatment of various diseases. However, further studies are required to elucidate the underlying mechanisms of the interactions between EA and gut microbiota and their health benefits. Continued investigation into EA and its metabolites is essential for advancing our understanding of their role in promoting human health and developing novel therapeutic applications.

Best Practices and Considerations for Conducting Research on Diet-Gut Microbiome Interactions and Their Impact on Health in Adult Populations: An Umbrella Review

Diet modulates gut microbiome composition and function. However, determining causal links between diet-gut microbiome interactions and human health is complicated by inconsistencies in the evidence, arising partially from variability in research methods and reporting. Widespread adoption of standardized best practices would advance the field but require those practices to be identified, consolidated, and discussed. This umbrella review aimed to identify recommended best practices, define existing gaps, and collate considerations for conducting research on diet-gut microbiome interactions and their impact on human health outcomes. Reviews meeting inclusion criteria and published after 2013 were identified using a systematic search. Recommendations, considerations, and gaps relating to the best practices associated with study design, participant selection, dietary intervention/assessment, biological sample collection, and data analysis and reporting were extracted and consolidated. Eight narrative reviews were included. Several general points of agreement were identified, and a recurring theme was that best practices are dependent upon the research aims, outcomes, and feasibility. Multiple gaps were also identified. Some, such as suboptimal diet assessment methods and lack of validated dietary intake biomarkers, are particularly relevant to nutrition science. Others, including defining a "healthy" gut microbiome and the absence of standardized sample and data collection/analysis protocols, were relevant specifically to gut microbiome research. Gaps specific to diet-gut microbiome research include the underrepresentation of microbiome-modulating dietary components in food databases, lack of knowledge regarding interventions eliciting changes in the gut microbiome to confer health benefits, lack of in situ measurement methods, and the need to further develop and refine statistical approaches for integrating diet and gut microbiome data. Future research and cross-disciplinary exchange will address these gaps and evolve the best practices. In the interim, the best practices and considerations discussed herein, and the publications from which that information was extracted provide a roadmap for conducting diet-gut microbiome research. This trial was registered at PROSPERO as CRD42023437645.

De-coding the complex role of microbial metabolites in cancer

The human microbiome, an intricate ecosystem of trillions of microbes residing across various body sites, significantly influences cancer, a leading cause of morbidity and mortality worldwide. Recent studies have illuminated the microbiome's pivotal role in cancer development, either through direct cellular interactions or by secreting bioactive compounds such as metabolites. Microbial metabolites contribute to cancer initiation through mechanisms such as DNA damage, epithelial barrier dysfunction, and chronic inflammation. Furthermore, microbial metabolites exert dual roles on cancer progression and response to therapy by modulating cellular metabolism, gene expression, and signaling pathways. Understanding these complex interactions is vital for devising new therapeutic strategies. This review highlights microbial metabolites as promising targets for cancer prevention and treatment, emphasizing their impact on therapy responses and underscoring the need for further research into their roles in metastasis and therapy resistance.

Regulation of innate lymphoid cell by microbial metabolites

Innate lymphoid cells (ILCs) are a unique category of immune cell that lack antigen-specific receptors yet possess the capacity to detect signals from the surrounding tissue. The majority of ILCs reside in the lymphoid and mucosal tissues, maintaining close associations with the microbiota. Beyond the contributions of accessory cells and adaptive immune cells, accumulating studies demonstrate that microbial metabolites serve a crucial role in mediating the relationship between ILCs and the microbiota. In this review, we highlight and summarize the roles of microbial metabolites from different sources in modulating ILC subsets, proposing these metabolites as potential therapeutic mechanisms in ILC-mediated diseases.

Betaine regulates the gut-liver axis: a therapeutic approach for chronic liver diseases

Chronic liver disease is defined by persistent harm to the liver that might result in decreased liver function. The two prevalent chronic liver diseases are alcohol-associated liver disease (ALD) and metabolic dysfunction-associated steatotic liver disease (MASLD). There is ample evidence that the pathogenesis of these two chronic liver diseases is closely linked to gastrointestinal dysfunctions that alters the gut-liver crosstalk. These alterations are mediated through the imbalances in the gut microbiota composition/function that combined with disruption in the gut barrier integrity allows for harmful gut microbes and their toxins to enter the portal circulation and reach the liver to elicit an inflammatory response. This leads to further recruitment of systemic inflammatory cells, such as neutrophils, T-cells, and monocytes into the liver, which perpetuate additional inflammation and the development of progressive liver damage. Many therapeutic modalities, currently used to prevent, attenuate, or treat chronic liver diseases are aimed at modulating gut dysbiosis and improving intestinal barrier function. Betaine is a choline-derived metabolite and a methyl group donor with antioxidant, anti-inflammatory and osmoprotectant properties. Studies have shown that low betaine levels are associated with higher levels of organ damage. There have been several publications demonstrating the role of betaine supplementation in preventing the development of ALD and MASLD. This review explores the protective effects of betaine through its role as a methyl donor and its capacity to regulate the protective gut microbiota and maintain intestinal barrier integrity to prevent the development of these chronic liver diseases. Further studies are needed to enhance our understanding of its therapeutic potential that could pave the way for targeted interventions in the management of not only chronic liver diseases, but other inflammatory bowel diseases or systemic inflammatory conditions.

Modulation of intestinal signal transduction pathways: Implications on gut health and disease

The gastrointestinal (GI) tract is essential for nutrient absorption and protection against pathogens and toxins. Its epithelial lining undergoes continuous renewal every 3-5 days, driven by intestinal stem cells (ISCs). ISCs are primarily of two types: actively proliferating crypt base columnar cells (CBCs), marked by Lgr5 expression, and quiescent label-retaining cells (+4 LRCs), which act as reserves during stress or injury. Key signaling pathways, such as Wnt/β-catenin, Notch, bone morphogenetic proteins (BMPs), and epidermal growth factor (EGF), are crucial in maintaining epithelial homeostasis. These pathways regulate ISCs proliferation and their differentiation into specialized epithelial cells, including goblet cells, paneth cells, enteroendocrine cells, and enterocytes. Disruptions in ISCs signaling can arise from extrinsic factors (e.g., dietary additives, heavy metals, pathogens) or intrinsic factors (e.g., genetic mutations, metabolic changes). Such disruptions impair tight junction integrity, induce inflammation, and promote gut dysbiosis, often perpetuating a cycle of intestinal dysfunction. Chronic ISCs dysregulation is linked to severe intestinal disorders, including colorectal cancer (CRC) and inflammatory bowel disease (IBD). This review emphasizes the critical role of ISCs in maintaining epithelial renewal and how various factors disrupt their signaling pathways, jeopardizing intestinal health and contributing to diseases. It also underscores the importance of protecting ISCs function to mitigate the risk of inflammation-related disorders. It highlights how understanding these regulatory mechanisms could guide therapeutic strategies for preserving GI tract integrity and treating related conditions.

Role of Mushroom Polysaccharides in Modulation of GI Homeostasis and Protection of GI Barrier

Edible and medicinal mushroom polysaccharides (EMMPs) have been widely studied for their various biological activities. It has been shown that EMMPs could modulate microbiota in the large intestine and improve intestinal health. However, the role of EMMPs in protecting the gastric barrier, regulating gastric microbiota, and improving gastric health cannot be ignored. Hence, this review will elucidate the effect of EMMPs on gastric and intestinal barriers, with emphasis on the interaction of EMMPs with microbiota in maintaining overall gastrointestinal health. Additionally, this review highlights the gastroprotective effects and underlying mechanisms of EMMPs against gastric mucosa injury, gastritis, gastric ulcer, and gastric cancer. Furthermore, the effects of EMMPs on intestinal diseases, including inflammatory bowel disease, colorectal cancer, and intestinal infection, are also summarized. This review will also discuss the future perspective and challenges in the use of EMMPs as a dietary supplement or a nutraceutical in preventing and treating gastrointestinal diseases.

Crosstalk between bile acids and gut microbiota: a potential target for precancerous lesions of gastric cancer

As a critical juncture in the pathological continuum from gastritis to gastric cancer, precancerous lesions of gastric cancer (PLGC) are increasingly prevalent, significantly undermining the health of the global population. The primary constituents of bile, specifically bile acids (BAs), disrupt the equilibrium of gastric hormone secretion and compromise the structural integrity of the gastric mucosa, thereby facilitating gastric oncogenesis. Moreover, gut microbiota modulate host physiological and pathological processes through immune response regulation, metabolic pathway interference, and direct interaction with gastric tumor cells. Extensive research has elucidated that the metabolic dysregulation of BAs and gut microbiota, in concert with the resultant impairment of the gastric mucosa, are central to the pathogenesis of PLGC. In anticipation of future clinical preventive and therapeutic strategies, this review collates recent insights into the roles of BAs and gut bacteria in PLGC, examining their interplay and significance in the pathogenic mechanism of PLGC.

An In Vitro Cell Model of Intestinal Barrier Function Using a Low-Cost 3D-Printed Transwell Device and Paper-Based Cell Membrane

Current in vitro methods for intestinal barrier assessment predominantly utilize two-dimensional (2D) membrane inserts in standard culture plates, which are widely recognized for their inability to replicate the microenvironment critical to intestinal barrier functionality. Our study focuses on creating an alternative method for intestinal barrier function by integrating a 3D-printed transwell device with a paper-based membrane. Caco-2 cells were grown on a Matrigel-modified paper membrane, in which the tight junction formation was evaluated using TEER measurements. Neutrophil-like dHL-60 cells were employed for neutrophil extracellular trap (NET) formation experiments. Furthermore, intestinal barrier dysfunction was demonstrated using NET-isolated and Staurosporine interventions. Intestinal barrier characteristics were investigated through immunofluorescence staining of specific proteins and scanning electron microscopy (SEM). Our paper-based intestinal barrier exhibited an increased resistance in a time-dependent manner, consistent with immunofluorescence images of Zonulin Occludens-1 (ZO-1) expression. Interestingly, immunofluorescence analysis revealed changes in the morphology of the intestinal barrier and the formation of surface villi. These disruptions were found to alter the localization of tight junctions, impacting epithelial polarization and surface functionality. Moreover, we successfully demonstrated the permeability of a paper-based intestinal barrier using FITC-dextran assay. Hence, the 3D-printed transwell device integrated with a paper membrane insert presents a straightforward, cost-effective, and sustainable platform for an in vitro cell model to evaluate intestinal barrier function.

The intestinal barrier: a pivotal role in health, inflammation, and cancer

The intestinal barrier serves as a boundary between the mucosal immune system in the lamina propria and the external environment of the intestinal lumen, which contains a diverse array of microorganisms and ingested environmental factors, including pathogens, food antigens, toxins, and other foreign substances. This barrier has a central role in regulating the controlled interaction between luminal factors and the intestinal immune system. Disruptions of intestinal epithelial cells, which serve as a physical barrier, or the antimicrobial peptides and mucins they produce, which act as a chemical barrier, can lead to a leaky gut. In this state, the intestinal wall is unable to efficiently separate the intestinal flora and luminal contents from the intestinal immune system. The subsequent activation of the immune system has an important role in the pathogenesis of inflammatory bowel disease, as well as in metabolic dysfunction-associated steatohepatitis, primary sclerosing cholangitis, and colorectal cancer. Dysregulated intestinal barrier integrity has also been described in patients with chronic inflammatory diseases outside the gastrointestinal tract, including rheumatoid arthritis and neurodegenerative disorders. Mechanistic studies of barrier dysfunction have revealed that the subsequent local activation and systemic circulation of activated immune cells and the cytokines they secrete, as well as extracellular vesicles, promote proinflammatory processes within and outside the gastrointestinal tract. In this Review, we summarise these findings and highlight several new therapeutic concepts currently being developed that attempt to control inflammatory processes via direct or indirect modulation of intestinal barrier function.

Cordyceps militaris extract and cordycepin ameliorate LPS-challenged colonic damage in piglets by modulating the microbiota and metabolite profiles

Introduction

Cordyceps militaris extract (CME) and cordycepin (CPN) are biomolecules with a wide range of biological activities, including anti-inflammatory, antioxidant and anti-tumour effects. The research objective wasto investigate the influences of CME and cordycepin CPN on colonic morphology, microbiota composition and colonic metabolomics in lipopolysaccharide (LPS)-challenged piglets.

Methods

Twenty-four weaned castrated piglets were randomly divided into four groups: control group (fed basal diets), LPS group (fed basal diets), CPN-LPS group (basal diets + 60 mg/kg cordycepin), and CME-LPS group (basal diets + 60 mg/kg C. militarisextract). On the 21st day, the LPS, CPN-LPS, and CME-LPS groups received an injection of 100 μg/kg BW LPS, while the control group was given sterile saline.

Results

The findings demonstrated that CPN or CME attenuated intestinal morphology damage with LPS-challenged piglets. CPN and CME alleviated intestinal microbiota dysbiosis and metabolic disorders under LPS-challenged by enriching serum protein levels, regulating of inflammatory cytokine secretion and altering colonic microbial composition. Colonic microbiota analysis that the CPN improved the relative abundance of Acidobacteriota and inhibited Faecalibacterium, CME promoted the relative abundance of Prevotella and Lachnospiraceae NK4A136group. Meanwhile, the alleviation of colonic damage is achieved through modulation of metabolic pathways linked to tryptophan metabolism, biosynthesis of amino acids and butanoate metabolism.

Discussion

Conclusively, our preliminary findings reveal that CPN or CME could serve as a beneficial dietary supplement to alleviate gut diseases in weaning piglets.

Short-term subacute di(2-ethylhexyl) phthalate exposure disrupts gut microbiota, metabolome, liver transcriptome, immunity, and induces liver injury in rats

Di(2-ethylhexyl) phthalate (DEHP) is recognised as a pollutant with multiple health risks. In this study, multi-omics approaches were used to examine the alterations in immunity, gut microbiota and metabolome, and liver transcriptome in the rats with DEHP-induced subacute liver injury. Following short-term subacute DEHP exposure, the rats exhibited decreased body weight, increased liver weight, impaired liver function and immunity, and signs of liver injury. DEHP exposure reduced the richness, diversity, and evenness of gut microbiota, resulting in elevated levels of Lactobacillus, Romboutsia, and Alistipes and decreased levels of unclassified Muribaculaceae, Oscillibacter, and Akkermansia in the intestine. Multiple gut metabolic pathways were altered by DEHP, among which sphingolipid metabolism was enriched with the most differentially expressed metabolites. In the liver tissues of rats exposed to DEHP, lipid metabolism-related pathways were altered, including downregulated steroid biosynthesis and upregulated fatty acid degradation. In conclusion, the relevant findings suggest that DEHP can cause immune alteration, gut microbiota dysbiosis, gut metabolome disruption, liver transcriptome dysregulation, and result in liver injury in rats. These results could benefit the clinical diagnosis of DEHP-induced subacute liver injury.

Is there dietary macronutrient malabsorption in children with environmental enteropathy?

Assessing the digestive and absorptive capacity of the gastro-intestinal tract (GIT) using minimally- or non-invasive methods, particularly in children, has been difficult owing to the complex physiology and variability in functional measurements. However, measuring GIT function is increasingly important with the emerging relevance of childhood environmental enteropathy (EE) as a mediating factor in linear growth faltering, severe acute malnutrition, poor oral vaccine uptake and impaired cognition. In EE, sub-optimal nutrient digestion and absorption (malabsorption) forms the critical link to the conditions mentioned above. The present narrative review discusses probable mechanisms that can cause malabsorption of macronutrients, along with mechanistic and experimental evidence, in children (if not, in adults) with EE. The strengths and limitations of the human experimental studies are examined in relation to a battery of existing and potential tests that are used to measure malabsorption. From the available studies conducted in children, lactose and fat malabsorption are more likely to occur in EE. Breath tests (non-invasive) measuring carbohydrate (13C-starch/sucrose/lactose), fat (13C-mixed triglyceride) and dipeptide (benzoyl-L-tyrosyl-L-1-13C-alanine) malabsorption with modifications to the existing protocols seem suitable for use in children with EE. Future research should focus on understanding the degree of macronutrient malabsorption using these tests, in different settings, and link them to functional outcomes (such as growth, muscle strength, cognition).

Aryl hydrocarbon receptor (AHR) and nuclear factor erythroid-derived 2-like 2 (NRF2): An important crosstalk in the gut-liver axis

The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor, mainly involved in detoxification. However, in the intestine, metabolites derived from the diet, which are converted by a wide range of bacteria can also activate the AHR. This intestinal AHR activation plays a key role in maintaining the gut barrier by, for example, upregulating antimicrobial peptides and anti-inflammatory cytokines. Since the gut barrier influences the gut-liver axis by regulating the leaking of metabolites, bacteria, and endotoxins into circulation and particularly into the liver, the AHR is a key factor in the gut-liver axis. Vice versa, certain liver pathologies also influence the gut microbiome, thereby altering bacteria-derived activation of the AHR. Additionally, bile acids can impact the gut via the liver and thereby also affect the AHR. The aryl hydrocarbon receptor (AHR) interacts with several molecular factors, one of which is the nuclear factor erythroid-derived 2-like 2 (NRF2), a transcription factor primarily associated with regulating antioxidant stress responses. The interplay between AHR and NRF2 has been investigated in the context of various diseases; this review highlights the significance of this interaction within the framework of the gut-liver axis.

Pleurotus eryngii Mushrooms Fermented with Human Fecal Microbiota Protect Intestinal Barrier Integrity: Immune Modulation and Signalling Pathways Counter Deoxycholic Acid-Induced Disruption in Healthy Colonic Tissue

Background: This study explores the potential of the Pleurotus eryngii mushroom fermentation supernatant (FS-PEWS) as an intervention for mitigating sodium deoxycholate (SDC)-induced intestinal barrier dysfunction and inflammation. Methods: FS-PEWS was assessed for its protective effects against SDC-induced barrier dysfunction and inflammation using an in vitro Caco-2 cell model and ex vivo colonic biopsies from healthy adult donors, where barrier integrity, permeability, immunomodulation and receptor-mediated pathways were evaluated. Results: In Caco-2 cells, SDC exposure downregulated ZO-1, occludin, and claudin-1 expression, with FS-PEWS restoring ZO-1 and claudin-1 levels while maintaining cell viability. In colonic biopsies from healthy adults, FS-PEWS maintained tissue integrity and selectively mitigated transcellular permeability without affecting paracellular permeability when combined with the stressor. Additionally, FS-PEWS exhibited potent anti-inflammatory effects, reducing pro-inflammatory cytokines, e.g., TNF-α, IL-6, and IL-1β and modulating receptor-mediated pathways, i.e., TLR-4, dectin-1. Conclusions: These results demonstrate the potential of FS-PEWS to sustain intestinal barrier function and modulate immune responses under stress, highlighting its therapeutic potential for managing gut barrier dysfunction and inflammation associated with microbial metabolite-induced disruptions.

Modulation of the Neuro-Cancer Connection by Metabolites of Gut Microbiota

The gut-brain-cancer axis represents a novel and intricate connection between the gut microbiota, neurobiology, and cancer progression. Recent advances have accentuated the significant role of gut microbiota metabolites in modulating systemic processes that influence both brain health and tumorigenesis. This paper explores the emerging concept of metabolite-mediated modulation within the gut-brain-cancer connection, focusing on key metabolites such as short-chain fatty acids (SCFAs), tryptophan derivatives, secondary bile acids, and lipopolysaccharides (LPS). While the gut microbiota's impact on immune regulation, neuroinflammation, and tumor development is well established, gaps remain in grasping how specific metabolites contribute to neuro-cancer interactions. We discuss novel metabolites with potential implications for neurobiology and cancer, such as indoles and polyamines, which have yet to be extensively studied. Furthermore, we review preclinical and clinical evidence linking gut dysbiosis, altered metabolite profiles, and brain tumors, showcasing limitations and research gaps, particularly in human longitudinal studies. Case studies investigating microbiota-based interventions, including dietary changes, fecal microbiota transplantation, and probiotics, demonstrate promise but also indicate hurdles in translating these findings to clinical cancer therapies. This paper concludes with a call for standardized multi-omics approaches and bi-directional research frameworks integrating microbiome, neuroscience, and oncology to develop personalized therapeutic strategies for neuro-cancer patients.

Different lysine-to-methionine ratios in a low-protein diet affect the microbiome and metabolome, influencing the jejunal barrier function in Tibetan sheep

Introduction

The objective of this study was to evaluate the effects of the dietary lysine (Lys)/ methionine (Met) ratio in a low-protein diet on short-chain fatty acid (SCFA) profiles, villus morphology, antioxidant capacity, and immune status of the jejunum in Tibetan sheep.

Methods

A total of 90 weaned Tibetan sheep, each 2 months old with an initial weight of 15.37 ± 0.92 kg, were randomly divided into three treatment groups. These groups were supplemented with different Lys/Met ratios of 3 [low protein-high methionine (LP-H)], 2 [low protein-medium methionine (LP-M)], and 1 [low protein-low methionine (LP-L)] in the basal diet (10% crude protein). The feeding trial lasted 100 days, including a 10-day acclimation period and a 90-day experimental period.

Results

The hematoxylin-eosin (H&E) sections showed that the LP-L group had a significantly increased villus height compared to the LP-M and LP-H groups (p < 0.05). In addition, the LP-L group showed higher levels of Superoxide dismutase (SOD) activity and Total Antioxidant Capacity (T-AOC) concentrations (p < 0.05). A lower concentration of Interleukin-1 beta (IL-1β) was observed in the LP-H group (p < 0.05). The activities of α-amylase, chymotrypsin, and lipase were higher in the LP-L group compared to the LP-H group (p < 0.05). Bacterial sequencing showed that both Chao1 and ACE richness were significantly increased in the LP-L group (p < 0.05), suggesting that the species richness in the jejunum is connected to the ratio of dietary Lys/Met. Furthermore, lowering the dietary Lys/ Met ratio significantly increased the abundance of Romboutsia, the Ruminococcus gauvreauii group, the Lachnospiraceae NK3A20 group, Ruminococcus 2, and the Christensenellaceae R-7 group (p < 0.05) while decreasing the abundance of Methanobrevibacter (p < 0.05). Several differential metabolites, including beta-alanine, pantothenate, pantothenic acid, phosphoenolpyruvate, cysteine, adenosine 5'-diphosphate, isodeoxycholic acid, glutamate conjugated cholic acid, and 3-dehydrocholic acid, were significantly increased in the LP-L group (p < 0.05). The functional analysis based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) annotations indicated that these metabolites were mainly involved in pantothenate and CoA biosynthesis, ferroptosis, and the tricarboxylic acid cycle. Several genes related to barrier function, such as Occludin and Muc- 2, were upregulated in the LP-L group (p < 0.05), while IL-6 and TNF-α were downregulated (p < 0.05).

Discussion

Collectively, our results suggest that the dietary Met/ Lys ratio could affect the jejunal SCFA concentration by modulating the microbial community and regulating metabolism, thereby contributing to jejunal barrier function. Our findings provide a theoretical basis for the application of Lys/Met diet supplementation in the nutritional management of Tibetan sheep, particularly when reducing the dietary crude protein (CP) level.

Multifluid Metabolomics Identifies Novel Biomarkers for Irritable Bowel Syndrome

Background/Objectives: Irritable bowel syndrome (IBS) is a complex disorder affecting 10% of the global population, but the underlying mechanisms remain poorly understood. By integrating multifluid metabolomics, we aimed to identify metabolite markers of IBS in a large population-based cohort. Methods: We included individuals from TwinsUK with and without IBS, ascertained using the Rome III criteria, and analysed serum (232 cases, 1707 controls), urine (185 cases, 1341 controls), and stool (186 cases, 1284 controls) metabolites (Metabolon Inc.). Results: After adjusting for covariates, and multiple testing, 44 unique metabolites (25 novel) were associated with IBS, including lipids, amino acids, and xenobiotics. Androsterone sulphate, a sulfated steroid hormone precursor, was associated with lower odds of IBS in both urine (0.69 [95% confidence interval = 0.56-0.85], p = 2.34 × 10-4) and serum (0.75 [0.63-0.90], p = 1.54 × 10-3. Moreover, suberate (C8-DC) was associated with higher odds of IBS in serum (1.36 [1.15-1.61]; p = 1.84 × 10-4) and lower odds of IBS in stool (0.76 [0.63-0.91]; p = 2.30 × 10-3). On the contrary, 32 metabolites appeared to be fluid-specific, including indole, 13-HODE + 9-HODE, pterin, bilirubin (E,Z or Z,Z), and urolithin. The remaining 10 metabolites were associated with IBS in one fluid with suggestive evidence (p < 0.05) in another fluid. Finally, we identified androgenic signalling, dicarboxylates, haemoglobin, and porphyrin metabolism to be significantly over-represented in individuals with IBS compared to controls. Conclusions: Our results highlight the utility of a multi-fluid approach in IBS research, revealing distinct metabolic signatures across biofluids.

Akkermansia muciniphila identified as key strain to alleviate gut barrier injury through Wnt signaling pathway

As the largest mucosal surface, the gut has built a physical, chemical, microbial, and immune barrier to protect the body against pathogen invasion. The disturbance of gut microbiota aggravates pathogenic bacteria invasion and gut barrier injury. Fecal microbiota transplantation (FMT) is a promising treatment for microbiome-related disorders, where beneficial strain engraftment is a significant factor influencing FMT outcomes. The aim of this research was to explore the effect of FMT on antibiotic-induced microbiome-disordered (AIMD) models infected with enterotoxigenic Escherichia coli (ETEC). We used piglet, mouse, and intestinal organoid models to explore the protective effects and mechanisms of FMT on ETEC infection. The results showed that FMT regulated gut microbiota and enhanced the protection of AIMD piglets against ETEC K88 challenge, as demonstrated by reduced intestinal pathogen colonization and alleviated gut barrier injury. Akkermansia muciniphila (A. muciniphila) and Bacteroides fragilis (B. fragilis) were identified as two strains that may play key roles in FMT. We further investigated the alleviatory effects of these two strains on ETEC infection in the AIMD mice model, which revealed that A. muciniphila and B. fragilis relieved ETEC-induced intestinal inflammation by maintaining the proportion of Treg/Th17 cells and epithelial damage by moderately activating the Wnt/β-catenin signaling pathway, while the effect of A. muciniphila was better than B. fragilis. We, therefore, identified whether A. muciniphila protected against ETEC infection using basal-out and apical-out intestinal organoid models. A. muciniphila did protect the intestinal stem cells and stimulate the proliferation and differentiation of intestinal epithelium, and the protective effects of A. muciniphila were reversed by Wnt inhibitor. FMT alleviated ETEC-induced gut barrier injury and intestinal inflammation in the AIMD model. A. muciniphila was identified as a key strain in FMT to promote the proliferation and differentiation of intestinal stem cells by mediating the Wnt/β-catenin signaling pathway.

Targeting Helicobacter pylori Through the "Muco-Microbiotic Layer" Lens: The Challenge of Probiotics and Microbiota Nanovesicles

The muco-microbiotic layer represents a critical biological frontier in gastroenterology, emphasizing the intricate interplay between the protective mucus, its resident microbiota, and extracellular vesicles. This review explores the functional morphology of the gastric mucosa, focusing on the gastric muco-microbiotic layer, its role as a protective barrier, and its dynamic interaction with some of the most insidious pathogens such as Helicobacter pylori (H. pylori). Highlighting the multifaceted mechanisms of H. pylori pathogenesis, we have delved into bacterial virulence factors, host immune responses, and the microbiota's regulatory effects. Novel therapeutic strategies for H. pylori eradication, including traditional antibiotic therapies and emerging adjuvant treatments like probiotics and probiotic-derived extracellular vesicles, are critically examined. These findings underscore the potential of targeting nanovesicular interactions in the gastric mucosa, proposing a paradigm shift in the management of H. pylori infections to improve patient outcomes while mitigating antibiotic resistance.

Administration of a Recombinant Fusion Protein of IFN-γ and CD154 Inhibited the Infection of Chicks with Salmonella enterica

The cytokines IFN-γ and CD154 have been well established, and they play pivotal roles in immune protection against Salmonella in mice, but their effects and specific mechanisms in Salmonella-infected chickens are less understood. In this study, we conducted animal experiments to screen the highly immunoprotective chIFN-γ-chCD154 fusion protein compared with single protein chIFN-γ or chCD154 in white Leghorn chickens. The results showed that compared with separate pretreatments with chIFN-γ and chCD154, the fusion protein, chIFN-γ-chCD154, synergistically increased survival of infected chickens, reduced bacterial load in feces and organs, and attenuated pathological damage to the liver and cecum. Pretreatment with chIFN-γ-chCD154 also increased humoral immune responses, expression of the tight junction proteins zo-1, occludin, and claudin-1, and the relative abundance of Enterococcus_cecorum, Lactobacillus_helveticus, and Lactobacillus_agilis, which protect against intestinal inflammation. Compared with single protein pretreatment, chIFN-γ-chCD154 significantly upregulated STAT1, IRF1, and GBP1 in infected chickens while decreasing mRNA expression of TLR4, MyD88, NF-κB, TNF-α, IL-6, and IL-1β. In summary, damage to the cecal epithelial barrier and the inflammation induced by S. typhimurium infection was alleviated by chIFN-γ-chCD154 pretreatment through a mechanism involving the TLR4/MyD88/NF-κB and IFN-γ/STAT/IRF1/GBP1 pathways.

Alteration of intestinal microbiota-intestinal barrier interaction interferes with intestinal health after microcystin-LR exposure in Lithobates catesbeianus tadpoles

There remains uncertainty regarding the influence of microcystin-leucine arginine (MC-LR) on amphibian intestinal health, specifically how MC-LR interferes with intestinal microbiota following exposure to environmental concentrations. In this study, Lithobates catesbeianus tadpoles were exposed to varying MC-LR concentrations (0, 0.5, and 2 µg/L) over a 30-day period. The aim was to investigate how altered interactions between tadpole intestinal microbiota and the intestinal barrier influence intestinal health following MC-LR exposure. Following exposure to the MC-LR at low ambient concentrations, tadpole intestinal tissue was damaged. It had increased permeability, reduced pathogen inhibition capacity, and impaired digestive function. Additionally, there was a significant increase in lipopolysaccharide content and upregulation of downstream response genes, including TLR4, MyD88, and NF-κB, within the intestinal tissue. Therefore, eosinophils' count and pro-inflammatory cytokines' expression increased. In addition, MC-LR exposure induced oxidative stress and mitochondrial structural damage by increasing the levels of reactive oxygen species in intestinal tissue. CytoC and Bax transcription, as well as caspase 9 and caspase 3 activities, increased significantly. Significant downregulation of Bcl-2 transcription promoted apoptosis in tadpole intestinal cells. MC-LR exposure disrupted intestinal microbiota and metabolism in tadpoles. Correlation analysis revealed a strong association between intestinal microbiota and oxidative stress, inflammation, immunity, and tissue damage in the intestine. Conclusively, this study provides the first demonstration that MC-LR significantly affects amphibian intestinal microbiota, highlighting tadpoles' susceptibility to environmental risks posed by MC-LR.

Therapeutic Potential of Vanillic Acid in Ulcerative Colitis Through Microbiota and Macrophage Modulation

This study investigated the protective effects of the dietary polyphenol vanillic acid (VA) on dextran sulfate sodium-induced acute ulcerative colitis (UC) in mice, focusing on its impact on the gut microbiota and inflammatory responses. VA was supplemented following dextran sulfate sodium administration, and key indicators, including body weight, disease activity index, colon length, spleen index, and inflammatory markers, were assessed. VA supplementation significantly alleviated UC symptoms, preserved intestinal barrier integrity, and reduced pro-inflammatory cytokine levels. Additionally, VA positively altered the gut microbiota composition, promoting beneficial bacteria such as Akkermansia muciniphila while suppressing the arachidonic acid metabolism pathway. Fecal microbiota transplantation confirmed that the VA-modified gut microbiota contributed to these protective effects. VA also facilitated macrophage polarization from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype, further mitigating inflammation. These findings highlight the potential of VA as a natural dietary intervention for UC, emphasizing its role in regulating the gut microbiota and inflammatory pathways, which may have significant nutritional relevance in managing inflammatory bowel diseases.

Konjac glucomannan and κ-carrageenan improve hepatic fatty acid metabolism and colonic microbiota in suckling piglet

Konjac glucomannan (KGM) and κ-carrageenan are polysaccharides that have garnered attention for their potential health benefits. This study aimed to evaluate the maternal supplementation of KGM and κ-carrageenan (SF) during later gestation and lactation on the effect of hepatic lipid metabolism and colonic microflora in offspring. Regarding antioxidant and inflammatory factors in the suckling piglet liver, our results showed that nuclear factor erythroid 2-related factor 2 (Nrf2) and interleukin (IL)-10 levels were significantly increased in the SF group (P < 0.05). In liver mitochondrial function, the mRNA levels of voltage-dependent anion channel 1 (VDAC1), fission 1 (Fis1), and peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) were significantly up-regulated in the SF group compared to the control (Con) group (P < 0.05). The mRNA level of peroxisome proliferator-activated receptor alpha (PPARα) was remarkably down-regulated in the SF group (P < 0.05). In the colonic microflora of suckling piglets, we found that the SF group increased the abundance of Megasphaera and reduced the abundance of Erysipelotrichaceae_unclassified. The occludin level was significantly increased in the SF group than in the Con group (P < 0.05). In summary, maternal supplementation with SF improves hepatic lipid metabolism and colonic microflora in suckling piglets.