Search Results (230)

Chronic inflammatory skin diseases, including atopic dermatitis (AD) and psoriasis, are systemic immune-mediated disorders driven by dysregulated immune responses. The gut–skin axis is a bidirectional network linking intestinal microorganisms, their metabolites, and host immunity. It connects microbiome composition and function with systemic inflammation and cutaneous pathology, shaping disease-specific mechanisms such as Th2/IL-4/IL-13-mediated barrier dysfunction in AD and Th17/IL-23/IL-17-driven hyperproliferation in psoriasis. Microbiota-derived metabolites, including short-chain fatty acids, tryptophan-derived aryl hydrocarbon receptor ligands, and bile acid-dependent FXR/TGR5 signaling, modulate immune homeostasis and epithelial integrity. Gut dysbiosis, impaired metabolite production, and barrier dysfunction disrupt regulatory networks, amplifying inflammation. Microbiota-targeted interventions, including probiotics, synbiotics, postbiotics, and precision nutrition, may serve as adjunctive therapies, although further well-controlled clinical studies are needed. Integrating multi-omics, metabolomics, and functional microbial profiling, alongside investigations of the gut mycobiome and virome, will be critical to identify predictive biomarkers and optimize therapeutic strategies. These concepts remain mechanistically compelling but largely theoretical, requiring validation in longitudinal and interventional studies. Full article

Hybridization is pivotal for germplasm innovation, yet how reciprocal crossing regulates digestive characteristics in sub-cold-water fish remains unclear. This study systematically compared differences in intestinal morphology, physiological function, and microbial community assembly among herbivorous Schizothorax prenanti, carnivorous S. davidi, and their reciprocal hybrids using histological analysis, digestive enzyme assays, and 16S rRNA sequencing. Results indicated that parental intestinal characteristics were highly consistent with their feeding habits. Orthogonal hybrids exhibited a mosaic phenotype, combining the maternal muscular gut structure with high paternal-like lipase activity, and were characterized by an enrichment of the potential probiotic Lactococcus. In contrast, reciprocal hybrids presented a mismatch between morphology and function: despite developed hindgut folds, key digestive enzyme activities were low, and the gut microbiota was dominated by environmental bacteria such as Methylobacterium. Our findings indicate a spatially dependent assembly dynamic: the host genetic background strongly drives microbiome divergence in the anterior segments (foregut and midgut), whereas the long-term administration of a standardized diet ultimately promotes structural convergence in the hindgut. The orthogonal cross yielded a phenotype characterized by an apparent co-occurrence of specific host enzymes and distinct microbiota, suggesting an inferred physiological potential for lipid digestion that requires further multi-omics validation. These findings provide preliminary insights into the associations between genetic background and intestinal traits, providing a theoretical basis for the targeted breeding of Schizothorax species. Full article

Background/Objectives: Alcohol-related liver cirrhosis is a systemic disorder characterized by profound immune, metabolic and gut–liver axis dysregulation. Emerging evidence highlights a bidirectional interaction between the intestinal microbiota and host microRNAs (miRNAs), positioning this axis as a potential regulator of systemic homeostasis. However, human data exploring the impact of microbiota modulation on miRNA expression in advanced liver disease remain limited. Methods: Six patients with alcohol-induced liver cirrhosis underwent fecal microbiota transplantation (FMT). Safety was assessed through clinical and paraclinical monitoring at predefined intervals. Quality of life was evaluated pre- and post-intervention using a validated liver-specific questionnaire. Fecal expression of miR-21-5p, miR-122-5p, miR-125-5p, miR-146-5p and miR-155-5p was analyzed and correlations with clinical domains, demographic variables and hepatic encephalopathy severity were explored. Results: FMT was well tolerated, with no severe adverse events reported. Preliminary improvements were observed in total clinical score (3.22 [3.06–3.57] vs. 4.25 [4.20–4.26], p = 0.001) and in several quality-of-life domains, including abdominal symptoms, fatigue, systemic manifestations, activity and emotional function (p < 0.05), while worry/concern scores remained unchanged. miR-125 and miR-146 demonstrated consistent associations with clinical status both before and after FMT, whereas miR-21 correlated mainly with age and body mass index. Notably, miR-125 and miR-146 were also associated with post-FMT hepatic encephalopathy severity, supporting their potential value as molecular correlates of clinical response in this exploratory study. Conclusions: In this pilot study, FMT appeared safe and was temporally associated with improvements in clinical parameters in alcohol-related cirrhosis, alongside dynamic changes in fecal miRNA expression. These preliminary findings support a potential microbiota–miRNA interaction and warrant validation in larger, controlled longitudinal studies. Full article

Optimizing calcium metabolism is crucial for skeletal development and overall productivity in growing ruminants. Twenty-four Sunite lambs were randomly assigned to four groups and fed 0, 0.6, 1.2, or 2.4 g/(d·head) of γ-PGA for 60 days. Growth performance, serum parameters, duodenal morphology and calcium transporter expression, bone microarchitecture, and duodenal microbiota were analyzed. Supplementation with 1.2 g/(d·head) of γ-PGA (the M group) yielded optimal results, significantly improving final body weight and size. It enhanced duodenal health, evidenced by increased villus height, crypt depth, and microvilli density. Crucially, this dose significantly upregulated the expression of key duodenal calcium transporters (TRPV5/6, CaBPD9k, PMCA, VDR, claudin-12) and altered systemic calcium-regulating hormones (elevated calcitriol, PTH, FGF23). Bone micro-CT analysis revealed changes in trabecular architecture indicative of active remodeling. 16S rRNA sequencing and weighted OTU co-expression network analysis (WOCNA) revealed that γ-PGA reshaped the duodenal microbiota and identified core microbial modules strongly associated with host phenotypes. Genera such as [Eubacterium]_ruminantium_group, Fusicatenibacter, and Prevotella emerged as central hubs. In conclusion, dietary γ-PGA at 1.2 g/(d·head) enhances calcium absorption and bone metabolism in lambs through a coordinated modulation of intestinal integrity and calcium transport, systemic endocrine responses, and the duodenal microbial community, with specific microbiota identified as potential key mediators associated with these effects. Full article

Crohn’s disease (CD) is characterized by chronic intestinal inflammation accompanied by gut dysbiosis and redox imbalance. We investigated the role of dual oxidase-2 (DUOX2), a major epithelial source of reactive oxygen species (ROS), in linking oxidative stress to microbe–host crosstalk. DUOX2 expression was upregulated in human intestinal samples and was positively associated with inflammatory readouts, oxidative stress indices, and dysbiosis. Intestinal epithelial cell-specific Duox2 knockout (KO) mice exhibited reduced mucosal ROS, preserved barrier integrity, and attenuated dextran sodium sulfate (DSS)- and 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. Cohousing and fecal microbiota transplantation demonstrated that this protective phenotype was microbiota-dependent. Multi-omics profiling identified enrichment of Parabacteroides, particularly P. distasonis, in Duox2 KO mice, and oral supplementation with P. distasonis enhanced resistance to colitis. Mechanistically, DUOX2-derived oxidative stress constrained Parabacteroides growth, as P. distasonis displayed marked susceptibility to hydrogen peroxide, with excessive intracellular ROS accumulation and an absence of key antioxidant defenses—including peroxide reductase C (AhpC) and superoxide dismutase B (SodB)—indicating that epithelial DUOX2 shapes a hostile luminal redox niche unfavorable to these beneficial microbes. Pharmacological inhibition of DUOX2 with Compound 521 reduced oxidative stress, ameliorated colitis, and partially restored microbial balance. These findings establish a DUOX2–ROS–microbiota axis in which epithelial DUOX2 amplifies oxidative stress, remodels the gut ecosystem, and promotes inflammation, and highlights DUOX2 suppression or ROS-sensitive Parabacteroides as potential redox-centric therapeutic strategies for CD. Full article

It is known that the composition of the intestinal microbiota (IM) is associated with the pathogenesis of viral hepatitis. Hepatitis C virus (HCV) is an RNA virus that affects about 50 million people worldwide. HCV infection is considered a major risk factor for developing liver cirrhosis and hepatocellular carcinoma. The liver is closely related to bacterial components derived from the bacteria of the IM through the gut–liver axis, influencing host susceptibility to certain diseases, such as the development of hepatopathy associated with HCV infection. This review specifically evaluates the association of HCV infection with the bacterial IM, focusing on key aspects, such as the evolving intestinal dysbiosis during the natural history of the infection and the effect of treatment (antibiotics, direct-acting antivirals, pre/probiotics, and diet) in the management of these patients, in the different stages of the disease, up to HCC. Full article

Hyperuricemia is a metabolic disorder characterized by elevated serum uric acid levels and is increasingly linked to alterations in intestinal mucosal condition and gut microbiota composition. Probiotics have been proposed as safe, non-pharmacological approaches for managing hyperuricemia, but strain-specific evidence remains limited. This study aimed to evaluate the anti-hyperuricemic potential of Limosilactobacillus reuteri MBHC10138, isolated from human breast milk, and to examine its association with purine metabolism–related parameters, renal morphological features, intestinal barrier-associated markers, and gut microbiota composition. In vitro, MBHC10138 effectively degraded purine nucleosides that are metabolized into uric acid, suggesting its potential to reduce uric acid production in the host. In a mouse model of diet- and oxonate-induced hyperuricemia, oral administration of MBHC10138 significantly lowered serum uric acid levels to a level comparable with allopurinol treatment, while improving renal morphology. Histological and molecular analyses demonstrated restoration of the tight junction proteins zonula occludens-1 and occludin, indicative of enhanced intestinal barrier integrity. Furthermore, MBHC10138 administration modulated the gut microbiota by restoring microbial α-diversity and significantly increasing the relative abundances of the Clostridia vadinBB60 group and Oscillospiraceae, taxa associated with butyrate production, compared with the allopurinol-treated group. Collectively, these findings indicate that MBHC10138 exerts dual actions against hyperuricemia and intestinal barrier dysfunction through the regulation of purine metabolism, promotion of renal urate excretion, and modulation of gut microbial composition. MBHC10138 may thus represent a promising probiotic candidate for the prevention and adjunctive management of hyperuricemia-related metabolic disorders. Full article

Neurodegenerative disorders such as Alzheimer’s disease (AD), Parkinson’s disease (PD), and amyotrophic lateral sclerosis (ALS) share key molecular features, including neuroinflammation, oxidative stress, mitochondrial dysfunction, and progressive neuronal loss. Increasing evidence indicates that gut dysbiosis and alterations in microbiota-derived metabolites are involved in these processes through multiple pathways along the gut–brain axis. However, while broad compositional changes are well-documented, a critical knowledge gap remains regarding the specific biochemical signal transduction pathways translating dysbiosis into pathology. This narrative review addresses this gap by synthesizing current human and experimental studies addressing gut microbiota alterations in AD, PD, and ALS, with particular emphasis on the biochemical and molecular mechanisms mediated by gut-derived metabolites. Dysbiosis in neurodegenerative diseases is frequently associated with reduced abundance of short-chain fatty acid (SCFA)-producing bacteria and altered metabolism of SCFAs, bile acids, tryptophan-derived indoles, trimethylamine-N-oxide (TMAO), and lipopolysaccharides (LPS). These microbial metabolites have been shown to modulate intestinal and blood–brain barrier integrity, influence Toll-like receptor- and G protein-coupled receptor-dependent signaling, regulate microglial activation, and affect molecular pathways related to protein aggregation in experimental models. In addition, emerging evidence highlights the involvement of oxidative and nitrosative stress, immune–metabolic crosstalk, and altered xenobiotic metabolism in microbiota–host interactions during neurodegeneration. By integrating microbiological, metabolic, and molecular perspectives, this review underscores the important and emerging role of microbiota-derived molecules in neurodegenerative disorders and outlines key chemical and metabolic pathways that may represent targets for future mechanistic studies and therapeutic strategies. Full article

This review examines how distinct gut microbial community configurations—characterized by differential enrichment of Bacteroides, Prevotella, Ruminococcus, Bifidobacterium, and Lachnospira—may be associated with variations in host redox homeostasis through microbiota-derived metabolites, including short-chain fatty acids, secondary bile acids, and tryptophan derivatives. These compositional patterns represent reproducible features across populations and correlate with differential disease susceptibility in metabolic disorders. While microbial communities exist along compositional continua rather than discrete clusters, stratification based on dominant patterns offers a pragmatic framework for interpreting large-scale microbiome datasets and guiding precision nutrition interventions. Observational evidence suggests Bacteroides-enriched communities may associate with pro-inflammatory signatures, whereas Prevotella- Ruminococcus, Proteobacteria, Bifidobacterium, and Lachnospira-enriched configurations may exhibit anti-inflammatory or antioxidant characteristics in certain populations. However, inter-population variability and species- and strain-level heterogeneity limit generalization. Condition-dependent effects are exemplified by Prevotella copri, which demonstrates pro-inflammatory responses in specific settings despite beneficial profiles in others. When dysbiosis compromises intestinal barrier integrity, microbial translocation may amplify chronic oxidative stress and immune activation. We evaluate therapeutic potential of beneficial genera including Lactobacillus and Bifidobacterium while examining the dose-dependent, context-specific, and sometimes paradoxical effects of key metabolites. Microbiota-stratified therapeutic strategies—personalizing dietary, probiotic, or prebiotic interventions to baseline community composition—show promise but remain at proof-of-concept stage. Current evidence derives predominantly from cross-sectional and preclinical studies; prospective interventional trials linking community stratification with oxidative stress biomarkers remain scarce. The community–redox relationships presented constitute a hypothesis-generating framework supported by mechanistic plausibility and observational associations, rather than established causal pathways. Future research should prioritize intervention studies assessing whether aligning therapeutic approaches with baseline microbial configurations improves outcomes in oxidative stress-related metabolic disorders. Full article

This study systematically characterized functional compartmentalization along the intestinal tract of New Zealand rabbits by analyzing mucosal tissue and luminal contents from distinct segments, including the duodenum, jejunum, ileum, cecum, and colon, using RNA-seq and 16S rRNA sequencing. Transcriptomic analysis revealed that differentially expressed genes identified between the small and large intestines were mainly enriched in digestion, absorption, and immune functions. Genes associated with the transport of amino acids, sugars, vitamins, and bile salts showed significantly higher expression in the small intestine, whereas genes related to water absorption, short-chain fatty acids (SCFAs), nucleotides, and metal ion transport were preferentially expressed in the large intestine. From an immunological perspective, genes involved in fungal responses were enriched in the small intestine, while bacterial response pathways and pattern recognition receptor (PRR) signaling genes were upregulated in the large intestine. Microbiota analysis demonstrated significantly greater diversity and abundance in the large intestine compared with the small intestine. Specifically, Proteobacteria and Actinobacteria were enriched in the small intestine, whereas Firmicutes, Verrucomicrobia, and Bacteroidetes dominated the large intestine. Correlation analysis further identified significant associations between gut microbiota composition and host genes involved in nutrient digestion and absorption. Together, these findings provide transcriptome-based evidence for regional specialization of nutrient transport, immune responses, and microbial ecology along the rabbit intestine. Full article

Human microbiota, a complex consortium of microorganisms co-evolved with the host, profoundly influences tissue development, immune regulation, and disease progression. Growing evidence shows that microbial metabolites and signaling molecules modulate key stem cell pathways—such as Hedgehog, Wnt/β-catenin, and Notch—thereby reprogramming stem cell fate toward tumor-suppressive or tumor-promoting outcomes. Specific taxa within oral, intestinal, and urogenital niches have been linked to cancer initiation, therapy resistance, and recurrence. In parallel, clinical studies reveal that microbiota composition affects infection dynamics: bacterial isolates from symptomatic urinary tract infections inhibit commensal growth more strongly than the reverse, with Gram-positive and Gram-negative strains displaying distinct interaction profiles. Collectively, these findings highlight microbiota’s dual role in regulating cellular plasticity and pathogenicity. Elucidating host–microbe and microbe–microbe mechanisms may guide microbiota-targeted interventions to improve cancer and infectious disease management. Full article

Desulfovibrio (DSV), sulfate-reducing gut bacteria that generate hydrogen sulfide (H₂S), can impact host health through diverse mechanisms including bile acid (BA) metabolism. Although intestinal overgrowth of DSV expands the BA pool and promotes liver injury, its causal role in hepatic pathophysiology remains incompletely defined. Here, by employing complementary interventions of cholic acid (CA) supplementation and the BA sequestrant cholestyramine in mouse models, we show that DSV-driven liver injury is mediated by aberrant BA metabolism coupled with gut microbial remodeling. CA alone induced overt hepatic damage, whereas supplemental DSV did not further exacerbate injury caused by excessive CA. Intervention with the BA sequestrant cholestyramine markedly attenuated DSV-elicited hepatic inflammatory and histological alterations, which were associated with an upregulation of the intestinal BAs pool. Hepatic expression of BAs synthetic genes Cyp7a1 and Cyp8b1 verified a negative-feedback regulation of BA metabolism upon treatments. 16S rRNA gene sequencing revealed that CA, DSV, and the cholestyramine all significantly influenced the gut microbiota. CA reduced microbial richness and drove community separation, while DSV intervention under high BA conditions enriched specific biomarkers including Eubacterium ventriosum and Enterorhabdus. Notably, the administration of cholestyramine attenuated these DSV-associated microbial shifts and further reduced overall species richness, confirming the integral role of BA dynamics in shaping the gut microbial community. Collectively, our research reveals the intricate link between DSV, BAs, and gut microbiota in liver injury, and suggests that modulation of BAs may hold therapeutic potential for DSV-associated liver hepatic conditions. Full article

A wide range of non-microbial contaminants—such as heavy metals, pesticide residues, antibiotics, as well emerging foodborne contaminants like micro- and nanoplastics and persistent organic pollutants—can enter the human body through daily diet and exert subtle yet chronic effects that are increasingly recognized to be gut microbiota-dependent. However, the relationships among multi-contaminant exposure profiles, dynamic microbial community structures, microbial metabolites, and diverse clinical or subclinical phenotypes are highly non-linear and multidimensional, posing major challenges to traditional analytical approaches. Artificial intelligence (AI) is emerging as a powerful tool to untangle the complex interactions between foodborne non-microbial contaminants, the gut microbiota, and host health. This review synthesizes current knowledge on how key classes of non-microbial food contaminants modulate gut microbial composition and function, and how these alterations, in turn, influence intestinal barrier integrity, immune homeostasis, metabolic regulation, and systemic disease risk. We then highlight recent advances in the application of AI techniques, including machine learning (ML), deep learning (DL), and network-based methods, to integrate multi-omics and exposure data, identify microbiota and metabolite signatures of specific contaminants, and infer potential causal pathways within “contaminant–microbiota–host” axes. Finally, we discuss current limitations, such as data heterogeneity, small-sample bias, and interpretability gaps, and propose future directions for building standardized datasets, explainable AI frameworks, and human-relevant experimental validation pipelines. Overall, AI-enabled analysis offers a promising avenue to refine food safety risk assessment, support precision nutrition strategies, and develop microbiota-targeted interventions against non-microbial food contaminants. Full article

The ruminant gastrointestinal tract hosts a complex microbial ecosystem vital for nutrient absorption, with each segment displaying distinct morphological and microbial compositional features compared to monogastric animals. While most studies rely on fecal samples, these fail to capture region-specific variations, limiting insight into microbe–physiology adaptations. In this study, we investigated Elaphodus cephalophus by measuring circular, longitudinal, and mucosal layer thickness across intestinal segments and by profiling bacterial and fungal communities via 16S and its rRNA sequencing. The results found that the stomach had the thickest circular (484.2 μm) and longitudinal (385.2 μm) muscle layers among all gastrointestinal segments. The thickness of the circular and longitudinal muscle layers in the stomach and duodenum showed a highly consistent variation trend (r > 0.74). Bacterial diversity was highest in the stomach and lowest in the ileum; cecal and rectal communities were similar but distinct from those in the duodenum, ileum, and stomach. Firmicutes and Bacteroidota dominated the bacterial phyla. Fungal abundance and diversity peaked in the cecum and were lowest in the stomach; Ascomycota was overall dominant, whereas Basidiomycota was most abundant in the duodenum. This study provides baseline descriptive data on the gastrointestinal muscle layer morphology and gut microbiota of Elaphodus cephalophus, establishing a basis for further study. Full article

Disruption of the gut-microbiome-brain axis contributes to the development of chronic inflammation, impaired intestinal barrier integrity, and progressive tissue damage, ultimately reducing quality of life and increasing risk of comorbidities, including neurodegenerative diseases. Current therapies are often limited by adverse effects and insufficient long-term efficacy, highlighting the need for more comprehensive therapeutic approaches. Berberine (BRB), a plant-derived isoquinoline alkaloid, has attracted growing attention due to its pleiotropic immunomodulatory, neuroprotective, and gut-homeostasis-modulating properties, which involve reshaping the gut microbiota and underscore its therapeutic relevance within the gut–microbiome–brain axis. The aim of this review is to synthesize current scientific evidence regarding the anti-inflammatory mechanisms of BRB in inflammatory bowel disease (IBD). We compare its activity with first-line therapies and discuss its impact on microbial composition, including the bidirectional regulation of specific bacterial taxa relevant to intestinal and systemic disorders that originate in the gut. Furthermore, we emphasize that gut bacteria convert BRB into bioactive metabolites, contributing to its enhanced intraluminal activity despite its low systemic bioavailability. By integrating molecular and microbiological evidence, this review fills a critical knowledge gap regarding the comprehensive therapeutic potential of BRB as a promising candidate for future IBD interventions. The novelty of this work lies in unifying fragmented findings into a framework that explains how BRB acts simultaneously at the levels of host immunity, microbial ecology, and neuroimmune communication—thus offering a new conceptual model for its role within the gut–microbiome–brain axis. Full article