Search Results (8,558)

The formulation of the gut–brain–microbiota axis (GBA) theory has led to new research directions that have expanded our understanding of the pathogenesis, phenotypic variability, and clinical course of Parkinson’s disease (PD). Models of PD pathogenesis, based on the Braak hypothesis, suggest a subtype of the disease in which pathological changes begin in the gut many years before the onset of brain pathology and the manifestation of motor symptoms. Gut microbiota may influence nervous system function along the GBA by influencing intestinal permeability, chronic inflammation, and α-synuclein aggregation. Accumulating evidence suggests that the gut microbiota may also regulate the synthesis and metabolism of neurotransmitters, including dopamine (DA), serotonin (5-HT), acetylcholine (ACh) and γ-aminobutyric acid (GABA), both in the gut and brain, and indirectly stimulate central nervous system activity via the vagus nerve, which receives signals from the enteric nervous system. Research on the effects of microbiota on GBA has paved the way for the identification of novel treatment strategies, including probiotics, prebiotics, synbiotics, postbiotics, antibiotics, and fecal microbiota transplantation (FMT), aimed at not only symptomatic but also disease-modifying treatment of PD. In this article, we propose a novel approach to GBA as a link between gut microbiota and gut and brain neurotransmitter metabolism in PD. We review the latest research on the gut epithelial barrier. We analyze and summarize the potential of therapeutic interventions targeting gut microbiota and their impact on neurotransmitter regulation in PD. Full article

Enterotoxigenic Escherichia coli (ETEC) causes severe intestinal infections in animals and threatens public health under the One Health framework. Most conventional studies focus on acute short-term ETEC infection, while natural persistent colonization oftern induces chronic intestinal mucosal compensatory remodeling in hosts. This study evaluated the protective effects of giant panda-derived Weissella confusa BSP201703 against chronic ETEC-induced intestinal damage using a giant panda fecal microbiota-associated (GPF) mouse model. Seventy-two Kunming mice were divided into six groups: blank control (C1), GPF control (C2), ETEC control (C3), and three W. confusa BSP201703 groups at low (1.0 × 10⁷ cfu/mL, W1), medium (1.0 × 10⁸ cfu/mL, W2), and high (1.0 × 10⁹ cfu/mL, W3) doses. Mice were first subjected to continuous ETEC challenge for 5 days to establish stable chronic intestinal injury, followed by a subsequent 5-day intervention with probiotic or sterile PBS for repairing existing damage. Growth performance, histopathology, serum D-lactate, SIgA, tight junction genes (ZO-1, Occludin, Claudin-1), and gut microbiota were analyzed. Histomorphologically, the chronic ETEC challenge induced compensatory increases in ileal villus height and crypt depth, which differed from typical acute necrotic atrophy. W. confusa BSP201703 mitigated ETEC-induced damage, reduced serum D-lactate (p < 0.05), increased SIgA, and upregulated tight junctions (p < 0.05). Microbial results demonstrated that medium-dose W2 maximized microbial diversity, while W1/W3 selectively enriched beneficial Bacteroidetes, Clostridium cluster IV, and Clostridium cluster XIVa taxa, confirming that moderate doses yielded optimal protection. In conclusion, W. confusa BSP201703 relieves ETEC injury by enhancing intestinal barrier function and regulating gut microbiota, highlighting its potential as a wildlife probiotic for One Health applications. Full article

Probiotics are known to improve gut microbiota balance, enhance food digestion, and support overall health. Among these, Bacillus species are particularly promising due to their safety, spore-forming ability, environmental resilience, and diverse enzymatic activities. However, most Bacillus probiotics used in industry are of terrestrial origin, leaving marine-derived strains largely unexplored. Utilising the untapped potential of marine microbial biomass, this study presents a multi-stage methodology for identifying and evaluating marine-derived Bacillus strains with probiotic potential. A structured screening pipeline was applied to 67 microbial isolates from the Great Barrier Reef sponges. Initial selection focused on essential probiotic characteristics, including growth, stability, safety, and survival under gastrointestinal conditions. Strains meeting these criteria were then assessed for desirable properties, including digestive enzyme production and pathogen inhibition. Using this workflow, three marine-derived Bacillus strains were identified as potential probiotics, one of which demonstrated strong antimicrobial activity against Salmonella enterica at 5 and 10 mg/mL (p < 0.01). These findings demonstrate the capability of marine-associated Bacillus as novel bioproducts with functional antimicrobial properties. Full article

Background: Constipation is a common gastrointestinal (GI) state for which probiotics have shown promise as a relief. This study examined the laxative effects of the strain Bifidobacterium animalis subsp. lactis CECT 8145 (BPL1^®) in a loperamide-induced rat model of constipation. Methods: Fifty-nine rats were divided into control and loperamide-induced constipation groups. Animals received a 3-day intervention with either placebo or probiotic BPL1^® at two doses: 1.5 × 10⁸ CFU (colony-forming units) (low) and 3 × 10⁹ CFU (high). The study assessed several parameters to determine the probiotic’s effect, including: stool and gut characteristics, gastrointestinal transit time (GTT), gene expression and gut microbiome composition. Results: While loperamide significantly decreased stool number, weight and humidity, BPL1^® supplementation effectively restored these parameters, being more pronounced at a high dose. Microbiome analysis showed that BPL1^® at a low dose reduced the abundance of Muribaculaceae and Muribaculum gordoncarteri, associated with constipation. In addition, Muribaculaceae abundance was negatively correlated with stool humidity. Functional microbiome profiling indicated that BPL1^® suppressed pathways related to mucin degradation, vancomycin resistance and isoleucine biosynthesis while promoting L-lactate and pyridoxal-P (vitamin B6) biosynthesis, which may support gut motility and barrier integrity. Conclusions:Bifidobacterium animalis subsp. lactis BPL1^® exhibits potential as a functional probiotic for relieving constipation through improving stool excretion and consistency, inducing taxonomic changes and beneficial functional modulation of the intestinal microbiome. These findings justify further investigation into the mechanisms of BPL1^® as a probiotic for constipation management. Full article

Adolescence is a metabolically vulnerable period, during which rapid physiological maturation coincides with the dynamic remodelling of the gut microbiome. This narrative review summarises evidence from 2015 to 2025 to clarify how disturbances to the gut–liver axis driven by dysbiosis contribute to the development and progression of non-alcoholic fatty liver disease (NAFLD) in young people. Based on a systematic search of the databases PubMed, Scopus and Web of Science, we outline the basis of bidirectional communication between the gut and liver and emphasise how microbial imbalance alters the handling of lipids in the liver by enhancing de novo lipogenesis, impairing fatty acid oxidation and disrupting AMPK signalling and mitochondrial function. Consistent findings from clinical and experimental studies show that adolescents with NAFLD exhibit reduced microbial diversity, the enrichment of ethanol- and LPS-producing taxa, and altered short-chain fatty acid profiles. Each of these is associated with hepatic inflammation and metabolic reprogramming. Microbial molecules, including LPS, secondary bile acids and branched-chain amino acid metabolites, activate TLR4–NF-κB pathways, promote Kupffer cell activation and intensify oxidative stress. These mechanisms intersect with factors specific to adolescence, such as increased adiposity, hormonal shifts and diet-induced metabolic strain. Dietary patterns emerge as key modulators of these processes. Westernised diets promote dysbiosis and endotoxemia, whereas Mediterranean, fibre-rich and plant-based diets enhance SCFA production, strengthen epithelial integrity and modulate adiponectin-dependent hepatic metabolism. Micronutrient-sensitive epigenetic regulation, particularly that involving folate, choline and polyphenols, also plays a role in shaping lipid homeostasis and inflammatory tone. We also highlight emerging evidence that the activation of cytoprotective pathways, especially Nrf2, is dependent on lifestyle factors and links antioxidant-rich functional foods and physical activity to improved mitochondrial resilience and microbiome stability. We evaluate therapies targeting the microbiome, including probiotics, prebiotics, synbiotics and postbiotics, which reduce endotoxemia, restore microbial balance and complement dietary strategies. Thus, these findings emphasise the importance of age-specific, mechanistically informed interventions that integrate diet quality, microbial ecology, and the molecular pathways that govern metabolic health in adolescents with NAFLD. Full article

Periodontitis is a highly prevalent chronic inflammatory disease with significant oral and systemic consequences, including associations with cardiovascular disease, diabetes, and adverse pregnancy outcomes. Although mechanical debridement remains the cornerstone of therapy, adjunctive antibiotic use is increasingly limited by antimicrobial resistance, biofilm-associated tolerance, pharmacokinetic constraints, and disruption of the commensal microbiome, leading to inconsistent outcomes and disease recurrence. This review highlights the mechanistic limitations of conventional antibiotic therapies in periodontitis and critically examines emerging next-generation therapeutic strategies aimed at overcoming these challenges. Specifically, it explores antimicrobial peptides, quorum sensing inhibitors, nanotechnology-based drug delivery systems, host modulation approaches, and microbiome-targeted therapies, with emphasis on their molecular mechanisms, clinical relevance, and translational potential. By integrating microbial, host, and pharmacological perspectives, this review provides a comprehensive framework for advancing precision-guided periodontal therapy and supports the shift toward targeted, sustainable, and personalized treatment strategies. Full article

Background: Probiotics have emerged as an effective therapeutic intervention in critically ill patients receiving enteral nutrition, yet their use remains inconsistent across intensive care units (ICUs). Understanding knowledge, attitudes, and practices (KAP) among healthcare professionals (HCPs) is essential for optimizing evidence-based probiotic administration in enteral nutrition, identifying perceived implementation barriers, and examining associations between KAP scores and study variables. Methods: A multicenter, cross-sectional online survey was administered to ICU physicians, nurses, clinical dietitians, pharmacists, and respiratory therapists. Participants completed a self-reported questionnaire assessing their knowledge of probiotic mechanisms, indications, and safety; attitudes toward probiotic therapy; and current practices in probiotic administration during enteral feeding. Results: A total of 935 ICU HCPs participated. Overall knowledge was insufficient, with only 33.2% achieving high knowledge scores (mean: 12.4/18 points), whereas attitudes were moderately favorable, with 35.5% demonstrating positive attitudes (mean: 23.9/30 points). A majority of respondents (58.7%) reported recommending or prescribing probiotics, most frequently clinical dietitians (84.5%). KAP varied significantly by profession, age group, and years of experience (p < 0.01). The most reported barriers were a lack of information about available probiotic products (73.2%), limited knowledge (41.2%), limited availability of clinically proven products (37.8%), and cost concerns (29.7%). Conclusions: Although ICU HCPs show interest and cautious acceptance of probiotics in enteral feeding, knowledge gaps, attitudinal variability, and practice inconsistencies persist across disciplines. These findings highlight the critical need for targeted, multidisciplinary educational interventions and the development of standardized, evidence-based institutional protocols to optimize probiotic use and improve patient outcomes. Full article

Background/Objectives: Recently, a randomized clinical trial evaluated whether a six-month probiotic administration could reduce symptom severity in preschool children with Autism Spectrum Disorders (ASD), with (GI) or without (NGI) gastrointestinal symptoms. Significant positive changes were observed only in NGI children. A second explorative study on children prior to intervention identified a fecal metabolome fingerprint associated with ASD severity. Building on these findings, the present study aimed to assess whether metabolomics could monitor changes in ASD severity following probiotic administration using a subset of samples from the same trial. Second, this study aimed to identify fecal metabolites to be monitored in children to predict whether their autism severity may decrease after probiotic or placebo treatment. Methods: Evaluations of the fecal metabolome and microbiota could be completed on 57 children before and after a double-blind administration of a probiotic mixture or a placebo. Results: In NGI children the probiotic was found to influence the concentration of the amino acids aspartate, leucine, tryptophan, and valine, together with nicotinate and the short chain fatty acids acetate, butyrate, isobutyrate, and propionate. Lactobacilli and Sutterella showed significant changes in response to probiotic administration (p < 0.05). Acetate, 4-hydroxyphenyl, galactose, proline, and tyramine were identified as key fecal metabolites for prediction purposes. Conclusions: The present exploratory analysis, despite the small sample size, suggests that fecal metabolomics may provide a useful approach for monitoring and potentially for predicting changes in ASD severity following probiotics administration. Full article

Background: Beets are enriched in bioactive compounds with beneficial effects on cardiovascular function. Nitrate is a precursor for nitric oxide synthesis, exhibiting an effect on cardiomyocytes and myocardial ischemia/reperfusion, improving endothelial function and reducing arterial stiffness. Betanin, saponins and phenolic compounds, other beet compounds, can limit the generation of reactive oxygen species and modulate gene expression. However, it has been a challenge to develop beetroot formulations for the oral administration of these compounds while preserving pleasant sensory characteristics. Objective: The objective of this study was to develop an innovative dairy–beetroot powder drink, microencapsulated in polysaccharides, i.e., maltodextrin, cassava starch or a combination of both, that could be easily reconstituted. Key Results: The microencapsulated formulation following freeze-drying displayed low water activity (<0.30) and high solubility (>90%), with rapid dispersion in aqueous medium. Fourier transform infrared spectroscopy confirmed the preservation of functional groups from the dairy base and sugar beetroots. Thermogravimetry analyses pointed out a slight increase in thermal stability for the powder formulation. The microencapsulation efficiency of betalains reached 81% in the powder formulation that combined cassava starch and maltodextrin as encapsulation agents. The novel dairy–beetroot powder drink can be stored at room temperature, ensuring microbiological safety and preserving good sensory acceptance. Conclusions: Dairy–beetroot powder microcapsules emerge as an efficient food strategy to provide bioaccessible dietary nitrate and antioxidant compounds, overcoming flavor and stability limitations but still aiding in terms of its vascular and hemodynamic-protective effects. Full article

Bladder cancer (BCa) arises from the interaction between environmental exposures and the host’s immunity and microbiome. Once considered sterile, the urinary tract is now known to harbor a resident urinary microbiome (UM) that dynamically interacts with the immune system and is influenced by systemic immunomodulatory effects of the gut microbiome (GM) brought on by the emerging gut–bladder axis. Accumulating evidence links alterations in UM and GM leading to BCa development, progression, and recurrence. Loss of protective taxa (e.g., Lactobacillus, Bifidobacterium and Ruminococcus) and enrichment of pro-inflammatory or genotoxic bacteria (e.g., Fusobacterium, Acinetobacter, Prevotella and Enterobacteriaceae) are associated with immune evasion and systemic inflammation. Microbial metabolites, especially short-chain fatty acids (SCFAs), play a key role in shaping tumor immunity and show diagnostic and prognostic potential, with specific microbial signatures correlating with recurrence risk, survival, and treatment response. Therapeutically, growing evidence suggests that microbiome composition influences immunotherapy response, highlighting opportunities for microbiome-based interventions. This review aims to summarize the rationale to implement microbial modulation strategies (e.g., dietary modulation, probiotics, fecal microbiota transplantation (FMT), and emerging synbiotic or postbiotic approaches) while addressing their current limitations and future requirements in order to develop microbiome-guided therapies, diagnostics and prognostic tools for BCa. Full article

Osteoporosis is a major global health challenge, particularly among aging populations, underscoring the need for safe and effective nutritional interventions. Probiotics and their metabolites have emerged as promising candidates for modulating bone health via the gut-bone axis. In this study, we investigated the effects of a cell-free culture supernatant (CFS) from the food-grade bacterium Limosilactobacillus fermentum GBE18 on the proliferation, differentiation, and mineralization of MC3T3-E1 pre-osteoblasts. GBE18 CFS exhibited no cytotoxicity at concentrations ranging from 1% to 4% (v/v). Notably, 2% (v/v) CFS significantly enhanced alkaline phosphatase (ALP) activity and extracellular matrix mineralization (p < 0.05). Transcriptomic profiling revealed that differentially expressed genes were enriched in osteoblast-related processes and two key signaling pathways: Wnt/β-catenin and PI3K/Akt. Subsequent qRT-PCR and Western blot analyses confirmed the upregulation of critical regulators (Rspo2, Pdpk1, Malat1) and demonstrated coordinated activation of Akt phosphorylation, β-catenin stabilization, and Runx2 protein expression. Our findings indicate that GBE18 CFS promotes osteogenic differentiation through coordinated modulation of the PI3K/Akt and Wnt/β-catenin pathways. Consequently, this study provides mechanistic evidence supporting the potential application of L. fermentum GBE18-derived metabolites as functional food ingredients or dietary interventions for bone health and osteoporosis management. Full article

Graft-versus-host disease (GVHD) is one of the principal complications seen in the recipients of allogenic hematopoietic stem cell transplantation (allo-HSCT), and persists as a leading cause of post-transplant morbidity and mortality. Increasing evidence highlights the crucial influence of the gut microbiome (GM) on transplant outcomes. Microbial dysbiosis, characterized by reduced bacterial diversity and pathogenic overgrowth, is strongly associated with higher rates of complications and mortality. Patients with lower microbial diversity exhibit poorer overall survival (OS) and an increased incidence of acute GVHD (aGVHD). Conversely, restoration of beneficial commensal communities has been shown to enhance immune homeostasis, mitigate GVHD severity, and decrease infection risk. Emerging therapeutic strategies now focus on modulating the intestinal microbiome through dietary interventions, probiotics, prebiotics, and fecal microbiota transplantation (FMT). It has been demonstrated that bacterial metabolites, such as short-chain fatty acids (SCFAs) from the diet, especially a diet rich in fibers, reduce the occurrence/severity of GVHD by inducing regulatory T cells (Tregs), which release anti-inflammatory cytokines and regulate the host immune system. Hence, the implementation of dietary fibers (DFs) could increase beneficial commensals, Treg induction, and improve outcomes such as GVHD and OS in recipients of allo-HCT. Hereupon, this review addresses how a fiber-rich diet modulates GM composition, reinforces epithelial barrier integrity, and improves the efficacy of Treg-based immunotherapy by stabilizing their regulatory phenotype and increasing their functional persistence, ultimately leading to a reduction in GI complications associated with GVHD. Unlike prior reviews that primarily cover the microbiome–GVHD axis or Treg therapies in isolation, this review emphasizes fermentable dietary fibers as a mechanistically grounded, clinically actionable strategy to support Treg stability and persistence via microbiota-derived metabolites. We integrate mechanistic evidence with emerging clinical feasibility data and ongoing trials of prebiotic supplementation in allogeneic HSCT. Full article

Periodontitis is a chronic inflammatory disease driven by microbial dysbiosis and an exacerbated host immune response. This leads to progressive breakdown of periodontal tissues. Although scaling and root planing remains the standard treatment, its capacity to fully restore immune balance and host–microbiota homeostasis is limited. Probiotics have emerged as promising adjunctive strategies to modulate pathways involved in periodontal disease progression. This review aimed to evaluate current clinical evidence on the use of probiotics as adjuncts in periodontal therapy. The review followed the Scale for the Assessment of Narrative Review Articles criteria, applied exclusively as a reporting-quality framework. A literature search was conducted in MEDLINE via PubMed for manuscripts indexed through January/2026, using MeSH terms related to periodontitis and probiotics. Probiotics demonstrate potential as adjunctive agents in periodontal therapy, as evidenced by improvements in clinical parameters (probing depth, clinical attachment level, and/or bleeding on probing) reported in clinical studies. However, the findings remain heterogeneous across trials. Variability in probiotic strains, CFU concentrations, administration routes, and treatment durations highlights the need for standardized clinical protocols to improve comparability and reproducibility and better establish their clinical efficacy. Stronger, long-term evidence is required to standardize therapeutic protocols. Full article

Foodborne diseases represent a major public health concern, particularly those associated with dairy products contaminated with Staphylococcus aureus, a pathogen capable of producing heat-stable enterotoxins. This study evaluated the potential of native lactic acid bacteria (LAB) isolated from artisanal kefir grains as natural biocontrol agents in fermented dairy foods. Kefir grains obtained from three artisanal producers were microbiologically characterized, revealing LAB as the dominant group and the absence of Enterobacteriaceae. Strains belonging mainly to the genera Lactobacillus sensu lato, Leuconostoc, and Pediococcus were isolated and exhibited differentiated metabolic profiles. Safety assessment showed no hemolytic activity and an overall susceptibility to clinically relevant antibiotics, although genus-dependent intrinsic resistance patterns were observed. Several strains displayed enzymatic activities related to carbohydrate digestion and high tolerance to simulated gastrointestinal conditions, with survival rates exceeding 90% during both gastric and intestinal phases. Neutralized cell-free supernatant (CFS) demonstrated differential inhibitory activity, with significant antagonism of S. aureus and E. coli, comparable to those of commercial reference strains. In a yogurt model system stored at 4 °C, selected Lactobacillus and Pediococcus strains induced a progressive and significant reduction in S. aureus populations, achieving complete elimination to undetectable levels in shorter times than commercial probiotic strains. Overall, these results demonstrate that native LAB from artisanal kefir grains exhibit an adequate safety and functional profile, together with strong antagonistic activity, supporting their potential application as natural protective cultures to improve the food hygiene of fermented dairy products. Full article

Chemotherapy- and/or radiotherapy-induced oral mucositis (CRIOM) is a common complication in patients with head and neck cancer, driven largely by excessive proinflammatory cytokine signalling and treatment-associated bacterial dysbiosis. This narrative review synthesizes current mechanistic evidence and summarizes emerging therapeutic strategies targeting these pathways. Research indicates that elevated levels of IL-1β, IL-6, TNF, iNOS, and nitric oxide amplify tissue injury and ulceration, while disruption of oral and gut microbial communities, characterized by loss of beneficial commensals and enrichment of pathogenic taxa, further exacerbates mucosal inflammation. Anti-inflammatory agents, including pentoxifylline, atorvastatin, trans-caryophyllene, azilsartan, recombinant human IL-11, and low-level laser therapy have been shown in preclinical models to reduce cytokine levels and promote mucosal healing. Similarly, microbiome-targeted approaches, such as oral microbiota transplantation and multi-strain probiotic formulations, have demonstrated potential in restoring microbial balance and attenuating CRIOM severity, with current evidence including both preclinical and clinical studies. Overall, current findings highlight cytokine toxicity and dysbiosis as synergistic drivers of CRIOM and support anti-inflammatory and microbiome-modulating strategies as promising adjunctive approaches; however, further well-designed clinical studies are required to validate their efficacy and guide clinical translation. Full article