Search Results (533)

Infectious diseases present persistent and complex challenges to global public health, with conventional antibiotic therapies increasingly limited by antimicrobial resistance, microbiota disruption, and adverse effects. There is a critical need to explore complementary strategies that augment host defense mechanisms without exacerbating these limitations. Accumulating evidence underscores the integral role of the gut microbiota—a diverse microbial ecosystem within the gastrointestinal tract—in regulating systemic immunity and pathogen susceptibility. This review synthesizes recent advances from animal models to delineate the multi-faceted mechanisms by which commensal microbes and their metabolites confer protection against enteric and respiratory infections. Key processes include competitive exclusion for nutrients and ecological niches, production of antimicrobial compounds, reinforcement of intestinal barrier integrity, and orchestration of local and systemic immunity via gut–lung axes. We further discuss the potential of microbiota-targeted interventions to enhance treatment efficacy and patient outcomes. By integrating mechanistic insights with translational applications, this review aims to inform the rational design of next-generation anti-infective strategies grounded in microbial ecology and host immunobiology. Full article

Vascular calcification (VC) is a pathological process involving the deposition of mineral salts within the vascular wall, representing a significant risk factor for the development and progression of cardiovascular disease. The gut microbiota refers to the diverse microbial ecosystem inhabiting the gastrointestinal tract, including bacteria, fungi, viruses, and other microorganisms. This community exhibits considerable variability in both population density and taxonomic composition, with current estimates indicating approximately 10¹³–10¹⁴ microorganisms residing in the human gut. Recent studies suggest that metabolites produced by the gut microbiota may influence the pathogenesis of VC through the gut–vascular axis. This review consolidates current findings on the molecular mechanisms driving VC and examines the potential contribution of gut microbiota dysbiosis to vascular pathology. Particular attention is given to the functional roles of microbial metabolites such as short-chain fatty acids (SCFAs), trimethylamine N-oxide (TMAO), lipopolysaccharide (LPS), uremic toxins, secondary bile acids, and vitamin K in modulating calcific processes. In addition, current limitations in the existing literature are outlined, and potential therapeutic approaches, including probiotic use, prebiotic interventions, and targeted dietary strategies, are discussed in the context of their relevance for future clinical management of VC. Full article

The human gut microbiome is a complex ecosystem integral to host health, with butyrate-producing bacteria (BPB) playing a critical role in maintaining intestinal homeostasis. This scoping review explores the composition, function, and systemic influence of BPB, focusing on their metabolic product, butyrate, and its implications for gut integrity, immune modulation, and gut–brain axis (GBA) communication. Disruptions to BPB abundance, which is correlated with Western dietary patterns, food additives, and antibiotic exposure, are linked to gut dysbiosis and associated with a wide spectrum of chronic diseases, including inflammatory bowel disease (IBD), obesity, type 2 diabetes, neurodegenerative disorders, and psychiatric conditions. Butyrate supports colonocyte energy metabolism, reinforces epithelial barrier function, regulates goblet cell mucus production, and exerts anti-inflammatory effects via histone deacetylase inhibition and G-protein-coupled receptor signaling. The depletion of BPB and the resultant butyrate deficiency may represent a unifying pathophysiological mechanism underlying these conditions. Therapeutic strategies that restore BPB populations and butyrate levels, such as prebiotics, dietary fiber, and microbiota-targeted interventions, hold promise for mitigating inflammation and enhancing systemic health through microbiome modulation. Full article

Yi’an Reservoir is located on a major tributary of the Baoquan River and hosts abundant aquatic resources, with Cyprinus carpio, Carassius auratus, and Hemiculter leucisculus as the dominant fish species. Water quality parameters significantly shape fish gut microbiota, which in turn plays a crucial role in host physiological functions. This study aimed to characterize the water quality parameters in Yi’an Reservoir and identify the microbial communities in both the aquatic environment and fish guts (C. carpio, C. auratus, and H. leucisculus) through 16S ribosomal RNA sequencing. The objective was to examine the associations of water quality parameters and aquatic environmental microbiota with the assembly of gut microbial communities in fish inhabiting this reservoir system. The water quality parameters showed significant site-specific differences, of which temperature and dissolved oxygen were highest at Location B, while pH was highest at Location A. The Cyanobium_PCC-6307 was identified as a major differentially abundant taxon at the genera level across different sampling sites. Furthermore, the gut microbiota of the same fish species exhibited substantial variation across different sampling sites. Redundancy analysis identified distinct environmental drivers at each location. Specifically, pH, conductivity, and total dissolved solids (TDS) showed positive correlations with the gut microbiota at Location A. In contrast, temperature, dissolved oxygen (DO), and the environmental abundance of Cyanobium PCC-6307 were positively correlated with the gut microbiota at Locations B and C. This study provides important insights for the conservation and management of aquatic resources in reservoir ecosystems. Full article

Background/Objectives: This study examines the application of the novel double emulsion gel system for the delivery and release of encapsulated cannabidiol (CBD) and the probiotic strain Lactiplantibacillus plantarum DSM 24624. Methods: During a six-week experimental period comprising stabilization, treatment, and wash-out phases, the dynamic Simulator of the Human Intestinal Microbial Ecosystem (SHIME^®) model was employed to assess a system. The evaluation focused on the delivery of CBD and probiotics, as well as the system’s effects on microbial composition, diversity, and metabolic activity throughout the digestion process using 16S rRNA gene sequencing and digital PCR methods. Results: Microbial community analysis revealed significant shifts in both mucosal and luminal microbiota following supplementation. The treatment increased beneficial bacterial families such as Lachnospiraceae and Clostridiaceae, demonstrated effective delivery, release, and persistence of the probiotic L. plantarum, as well as enhanced butyrate and lactate production. Diversity analyses highlighted a transient rise in alpha diversity within the mucin layer and a decrease in the lumen, with significant changes in beta diversity across experimental phases. Conclusions: Findings suggest that double emulsion gel can be employed for the delivery of probiotics and CBD to the gastrointestinal tract. In addition, an innovative CBD-probiotic formulation can modulate gut microbiota composition and metabolic activity, suggesting its potential as a functional food innovation for intestinal health. However, the results are based on an in vitro model, which lacks the complexity of the human host environment, and further clinical studies are necessary to confirm the biological relevance and therapeutic potential of such delivery systems for gastrointestinal health. Full article

Background/Objectives: Apple pomace, a major by-product of juice production, represents both an environmental burden and an underutilized resource. This study aimed to enhance the nutritional value of apple pomace via solid-state fermentation (SSF) to develop a functional feed ingredient and systematically evaluate its effects on growth, metabolism, and intestinal health in weaned piglets. Methods: Apple pomace was fermented using a multi-species consortium (Geotrichum candidum, Saccharomyces cerevisiae, Rhizopus oryzae, Bacillus subtilis, and Trichoderma viride). A total of 180 weaned piglets were fed iso-nitrogenous diets containing 0, 2, 4, 6, 8, or 10% fermented apple pomace for 35 days. Growth performance, serum biochemical and immuno-antioxidant indices, diarrhea incidence, jejunal morphology, and fecal microbiota were analyzed. Results: Dietary fermented apple pomace supplementation showed dose-dependent effects. The 8% fermented apple pomace group exhibited optimal growth performance, with increased average daily gain and feed intake and reduced feed-to-gain ratio (p < 0.05). Serum analysis indicated enhanced protein synthesis, antioxidant capacity (T-AOC, SOD, GSH-Px), and immunoglobulin levels (IgA, IgG, IgM), along with reduced urea nitrogen and oxidative stress marker MDA. This group also had the lowest diarrhea rate, associated with improved jejunal villus morphology. Microbiota analysis revealed that 8% fermented apple pomace effectively increased α-diversity, promoted beneficial bacteria (e.g., lactic acid bacteria and butyrate-producing Clostridium sensu stricto_1), and suppressed pathogens (Escherichia coli, Salmonella, Streptococcus). Conclusions: Multi-species SSF successively enhanced the nutritional profile of apple pomace. Inclusion at 8% showed the most favorable response in terms of growth performance, metabolic profile, and immune–antioxidant status in weaned piglets, mediated through improved intestinal morphology and targeted modulation of the gut microbiota toward a more diverse and beneficial ecosystem. These findings support the high-value, functional utilization of apple pomace as a feed additive in swine nutrition. Full article

Background/Objectives: Carotenoids are bioactive pigments with well-established antioxidant and immunomodulatory properties, yet their impact on gut microbiota remains poorly understood from a chemical standpoint. This study explores how carotenoid structure and gastrointestinal stability shape microbial responses combining in vitro fermentation with bioinformatic analyses. Methods: Individual carotenoids (beta (β)-carotene, lutein, lycopene) and combined carotenoids, as well as algal-derived extracts were subjected to 48 h in vitro fermentation, and microbial composition and activity were assessed through sequencing and computational analysis. Results: β-carotene and lycopene promoted acid-tolerant taxa such as Escherichia-Shigella, whereas lutein, due to its higher polarity, supported more transient fluctuations. Mixtures and algal carotenoids exhibited synergistic effects, sustaining beneficial genera including Bifidobacterium and Bacteroides and promoting structured ecological trajectories. Conclusions: These findings provide a chemistry-driven perspective on how carotenoids act as modulators of microbial ecosystems, with direct implications for the formulation of carotenoid-enriched functional foods and dietary interventions. Full article

Celiac disease (CeD) is a chronic immune-mediated enteropathy triggered by dietary gluten in genetically predisposed individuals which also entails intestinal dysbiosis. This hallmark microbial imbalance provides a rationale for exploring interventions that could modulate the gut ecosystem. Cocoa is a bioactive food rich in polyphenols, theobromine, and fiber, compounds known to have an influence on both immune function and gut microbiota composition. Here, we investigated the effects of cocoa supplementation on the gut microbial profile and predicted functionality in DQ8-D^d-villin-IL-15tg mice, genetically predisposed to CeD. Animals were assigned to a reference group receiving a gluten-free diet (GFD), a gluten-containing diet group (GLI), or the latter supplemented with defatted cocoa (GLI + COCOA) for 25 days. The cecal microbiota was analyzed via 16S rRNA sequencing, and functional pathways were inferred using PICRUSt2. Goblet cell counts and CeD-relevant autoantibodies were measured and correlated with microbial taxa. Cocoa supplementation partially attenuated gluten-induced dysbiosis, preserving beneficial taxa such as Akkermansia muciniphila and Lactobacillus species while reducing opportunistic and pro-inflammatory bacteria. Functional predictions suggested differences in the predicted microbial metabolic potential related to amino acid, vitamin, and phenolic compound metabolism. Cocoa also mitigated goblet cell loss and was inversely associated with anti-gliadin IgA levels. These findings suggest that cocoa, as an adjuvant to a GFD, could be of help in maintaining microbial homeostasis and intestinal health in CeD, supporting further studies to assess its translational potential. Full article

Ants act as keystone species in terrestrial ecosystems, providing important ecosystem services. The large-scale production and application of GO constitute a predominant contributor to its inevitable environmental dispersion. Most GO toxicity studies have focused on plants, animals, and microorganisms, with limited research on ground-dwelling ants. In the study, we used Camponotus japonicus as a model to investigate the toxic effects of GO on ants by integrating physiological characteristics, gut microbiota and transcriptome profiling. Results showed that GO exposure induced mitochondrial dysfunction, as evidenced by mitochondrial ROS accumulation and elevated mitochondrial membrane permeability. Physiological assessments revealed that GO exposure induced oxidative stress. Specifically, GO treatment significantly suppressed superoxide dismutase (SOD) and catalase (CAT) activities, while enhancing peroxidase (POD) and carboxylesterase (CarE) activities and increasing the levels of malondialdehyde (MDA) and trehalose. Gut microbiota analyses showed that GO remarkably reduced the relative abundance of beneficial bacterial symbionts (e.g., Candidatus Blochmannia) and destabilized the whole community structure. Furthermore, transcriptome profiling revealed 680 differentially expressed genes (DEGs) in the ants after GO exposure, most of which were significantly enriched in pathways associated with oxidative phosphorylation. This study suggests that GO may compromise ant-mediated ecosystem function and provides a reference for understanding the environmental risks of GO. Our findings also offer new insights for protecting the ecosystem services of ants. Full article

Plastic pollution is a major global challenge, especially nanoplastics (NPs) emerging as harmful pollutants due to their small size, reactivity, and persistence in ecosystems. Among them, cigarette butts composed of cellulose acetate (CA) are one of the most widespread and hazardous sources of terrestrial NPs. In this study, the immunotoxic, biochemical, and histopathological effects of cellulose acetate nanoplastics (CA-NPs) derived from smoked cigarette butts (SCB-NPs), unsmoked cigarette butts (USCB-NPs), and commercial cellulose acetate (CCA-NPs) were evaluated on the earthworm Allolobophora caliginosa. Adult worms were exposed for 30 days to 100 mg/kg CA-NPs in artificial soil under controlled laboratory conditions. Results revealed that SCB-NPs induced the most pronounced alterations, including increased lysozyme and metallothionein levels, reduced phagocytic and peroxidase activities, and depletion of protein and carbohydrate reserves. Histological examination showed vacuoles in epithelial layer vacuolization, space between muscle fiber disruption, and degeneration in gut and body wall, especially under SCB-NP exposure. USCB-NPs and CCA-NPs caused milder but still significant effects. Taken together, these findings highlight that the high toxicity of SCB-NPs is due to the presence of combustion-derived toxicants (nicotine, polycyclic aromatic hydrocarbons, and heavy metals), which exacerbate oxidative stress, immune suppression, and tissue damage in soil invertebrates. This study underscores the ecological risk of cigarette butt-derived NPs and calls for urgent policy measures to mitigate their terrestrial impacts. Full article

Gut microbes play a crucial role in regulating physiological processes such as host energy metabolism, nutrient absorption, and environmental adaptation. The predicted functions of gut microbes can be influenced by many factors, both extrinsic and intrinsic to the hosts. The plateau pika is a key species in the alpine ecosystem of the Qinghai–Tibet Plateau. Previous research on the plateau pika primarily examined how extrinsic factors affected its gut microbiota. However, studies on intrinsic factors are scarce. Here, we used live-trapping to capture plateau pikas and collect cecum contents. Using metagenomic sequencing of cecum content samples, we characterized and compared the gut microbial composition and predicted function of plateau pika in adult (n = 9) and juvenile (n = 9) populations. The results indicated that Bacillota and Bacteroidete were the major bacterial phyla. The core gut microbial genera were the same, but the relative abundance of Oscillospira in juveniles was significantly lower than that in adults. The changes in the proportion of cellulose-degradation-related bacterial communities in juveniles suggest that they tend to choose low-fiber diets. In this study, we found no significant differences in the gut microbial composition and diversity, KEGG level 1 metabolic pathways, or CAZy class level between adult and juvenile plateau pikas. In total, the composition and predicted functions of cecal microorganisms in juvenile and adult male plateau pikas were not different. Regarding KEGG level 2 metabolic pathways, the juvenile group had a higher relative abundance of metabolic pathways for cofactors and vitamins, terpenoids, and polyketides, whereas the adult group had a higher relative abundance of energy metabolism. However, the resulting differences remain unclear. Therefore, future research should validate the above findings on a broader spatio-temporal scale and conduct cross-species comparisons to construct a microbial ecological framework for the health management of plateau wild animals. Full article

Microplastics (MPs) and antibiotics have emerged as contaminants of global concern, posing potential threats to ecosystem security and organismal health. To investigate the individual and combined toxicity of microplastics (PS-MPs) and sulfamethoxazole (SMX), we conducted a 120 h acute exposure experiment using embryo–larval zebrafish as a toxicological model. Our findings demonstrate that both PS-MPs and SMX can induce neurodevelopmental toxicity in embryo–larval zebrafish during embryonic development. Notably, PS-MPs and SMX exerted a significant synergistic effect. PS-MPs 1 µm in diameter were restricted to the chorion surface of pre-hatching zebrafish, whereas post-hatching, PS-MPs accumulated mainly in the gut and gills, with accumulation levels increasing progressively with exposure duration. Individual exposure to PS-MPs or SMX reduced spontaneous locomotion, decreased heart rate, and shortened body length in embryo–larval zebrafish. In addition to exacerbating these effects, coexposure further increased the incidence of malformations such as pericardial effusion and spinal curvature. PS-MPs and SMX significantly decreased the levels of dopamine (DA), serotonin (5-HT), and γ-aminobutyric acid (GABA) in zebrafish while also suppressing acetylcholinesterase (AChE) activity and increasing acetylcholine (ACh) levels. Moreover, upon coexposure at high concentrations, PS-MPs and SMX acted synergistically to reduce the levels of DA and GABA. The downregulation of key neurodevelopmental genes (elavl3, gap43, and syn2a) and related neurotransmitter pathway genes indicates that PS-MPs and SMX impaired structural development and functional regulation of the nervous system. An integrated biomarker response (IBR) index confirmed that PS-MPs and SMX significantly enhanced developmental neurotoxicity during early neurodevelopment in embryo–larval zebrafish through synergistic effects. Our study provides critical toxicological evidence for the scientific assessment of the ecological risks posed by microplastic–antibiotic cocontamination. Full article

This study successfully developed an oral vaccine for Type 1 Diabetes utilizing recombinant Lactococcus lactis expressing the GAD65 autoantigen. We conducted an in-depth investigation into its protective mechanisms in NOD mice, with a particular focus on its effects on the gut microbiota and metabolome. The administration of the GAD65-L. lactis vaccine resulted in a significant delay in diabetes onset and the preservation of pancreatic function. Our analyses revealed notable alterations in the gut microbial ecosystem, enhancing its diversity and the abundance of beneficial bacteria. Metabolomic profiling indicated time-dependent changes in metabolic pathways, with a marked enrichment of pyrimidine metabolism at 16 weeks and arachidonic acid metabolism at 24 weeks after vaccination by both GAD65-L. lactis and NZ9000-L. lactis. Integrated correlation analysis identified specific microbiota–metabolite interactions, including associations between Ruminiclostridium and lipid species in the GAD65-L. lactis group. These modifications in the microbial community and metabolic landscape were accompanied by enhanced immunoregulatory responses in intestinal LPLs, including expanded Treg populations and suppressed CD8⁺ T cells, a rising trend in IL-10-producing naive dendritic cells, and increased concentrations of TGF-β. Full article

Rosemary extract (RE), rich in carnosic and rosmarinic acid, which have antibacterial/antioxidant/anti-inflammatory effects, is a potential natural feed supplement for heat-stressed dairy buffaloes. This study systematically evaluated dietary RE effects on dairy buffaloes during hot weather. Twenty Mediterranean dairy buffaloes were randomly allocated into two groups for a 35-day trial: the control (CON) group receiving a basal diet, and the RE group receiving the same basal diet supplemented with 20 g/d of RE. Results showed RE tended to reduce buffalo body surface temperature; increased milk production, 4% fat-corrected milk, milk protein, lactose, and solids-not-fat; and optimized milk fatty acid profiles. In regard to blood, the RE group exhibited higher catalase activity, total antioxidant capacity, and concentrations of immunoglobulin A and M, together with lower concentrations of the pro-inflammatory cytokines interleukin-1β and tumor necrosis factor-α. Additionally, RE markedly elevated concentrations of total volatile fatty acid, acetate, propionate, and butyrate; improved microbial α-diversity indices (Sobs and Ace); and increased the abundances of Rikenellaceae_RC9_gut_group and Butyrivibrio spp., as well as the enrichment of multiple genera belonging to the family Lachnospiraceae. In conclusion, supplementing the diet of heat-stressed dairy buffaloes with 20 g/d of RE improves milk production and composition-related performance by optimizing the rumen ecosystem and enhancing systemic health status, with these effects observed as short-term responses under the conditions of the present study. Full article

Gut microbial community assembly involves a critical bioenergetic trade-off, yet the gut microbes with roles in influencing intestinal metabolic homeostasis remain poorly understood in pelagic ecosystems. A central unresolved question is whether microbiome structure is primarily governed by stochastic geographic drift or by deterministic metabolic filters imposed by diet. Here, we test the metabolic release hypothesis, which posits that access to high-quality prey physiologically “releases” the host from obligate dependence on diverse fermentative symbionts. By integrating δ15N analysis with 16S rRNA metabarcoding in the anchoveta from the South Pacific waters (Engraulis ringens), we reveal a profound, diet-induced restructuring of the gut ecosystem. We demonstrate that trophic ascent triggers a deterministic collapse in microbial alpha diversity (rs = −0.683), driven by the near-complete competitive exclusion of fermentative bacteria (rs = −0.874) and the resulting dominance of a specialized proteolytic core. Mechanistically, the bioavailability of zooplankton-derived protein favors efficient endogenous hydrolysis over costly microbial fermentation, rendering functional redundancy obsolete. Crucially, we find that while metabolic function converges, taxonomic identity remains geographically structured (r = 0.532), suggesting that local environments supply the specific taxa to fulfill universal metabolic roles. These findings establish a link between δ15N as a nutritional physiology proxy of anchoveta and its gut for microbial functional state, bridging the gap between nutritional physiology and ecosystem modeling to better inform the management of global forage fish stocks. Full article