Search Results (413)

Male infertility contributes substantially to couple infertility, and a large proportion of cases remain idiopathic. Dysbiosis within the gut, seminal, and urinary microbiomes has been associated with impaired semen parameters, reproductive tract inflammation, and oxidative stress. This narrative review, informed by a structured literature search, summarizes current evidence for the gut–testis axis and the androbactome in male infertility and discusses mechanistic pathways linking microbial imbalance to sperm dysfunction. Proposed mechanisms include immune activation, increased oxidative stress, endocrine and metabolic perturbations, and disruption of epithelial barriers, including the blood–testis barrier. Early clinical trials report that selected probiotic or synbiotic formulations may be associated with improvements in one or more World Health Organization (WHO) semen parameters and with reductions in oxidative or inflammatory biomarkers (surrogate laboratory endpoints; pregnancy and live-birth outcomes are rarely reported and remain unproven) in selected populations, such as idiopathic infertility and the post-varicocelectomy setting. Given patient heterogeneity, a personalized approach requires prespecified clinical phenotypes and measurable monitoring targets, rather than indiscriminate supplementation. At present, probiotics should be considered an adjunct rather than a stand-alone therapy. Well-designed, contamination-aware microbiome studies and adequately powered randomized trials with clinically meaningful endpoints, including pregnancy and live birth, are required before routine clinical implementation. This synthesis is intended to support personalized counseling and trial design by clarifying candidate phenotypes, appropriate monitoring endpoints, and realistic limitations of current evidence. Full article

Chronic rhinosinusitis (CRS) is a heterogeneous inflammatory disease of the nasal and paranasal sinus mucosa with substantial impact on quality of life. Although atopy and/or allergic rhinitis frequently coexist with CRS, often alongside type 2-skewed inflammation, the extent to which allergic mechanisms define a discrete CRS entity remains debated, in part due to inconsistent operational definitions and overlapping clinical phenotypes. In parallel, culture-independent sequencing studies have reframed CRS as a disorder of host–microbe interactions, with many cohorts reporting reduced sinonasal microbial diversity, enrichment of potentially pathogen taxa (including Staphylococcus aureus), and biofilm-associated community states. However, causality and directionality remain uncertain. In this narrative review, we synthesize evidence at the interface of epithelial barrier dysfunction, type 2 cytokine networks (IL-4/IL-13/IL-5), and microbiome dysbiosis, highlighting where data are consistent across studies versus where findings are heterogeneous or predominantly associative. We discuss representative allergy-associated CRS prototypes such as allergic fungal rhinosinusitis and central compartment atopic disease as clinical models to interrogate these interactions, while distinguishing them from non–IgE-mediated type 2 entities such as aspirin-exacerbated respiratory disease. We also summarize current data linking atopy to sinonasal microbial signatures and discuss emerging microbiome-directed interventions (topical probiotics, bacteriophages, and microbiota transfer concepts) alongside biologics and precision anti-inflammatory therapies. Finally, we highlight key knowledge gaps, including the limited endotype-resolved and longitudinal studies, variable allergic phenotyping in microbiome research, and the need for standardized definitions and biomarker-driven stratification to clarify clinical utility and to guide mechanism-informed therapeutic trials. Full article

Colorectal cancer (CRC) cachexia is a multifactorial, treatment-limiting syndrome characterized by progressive loss of skeletal muscle with or without loss of fat mass, accompanied by systemic inflammation, anorexia, metabolic dysregulation, and impaired treatment tolerance. Despite decades of work, cachexia remains clinically underdiagnosed and therapeutically underserved, in part because canonical models treat tumor-derived factors and host inflammatory mediators as a largely ‘host-only’ network. In parallel, CRC is strongly linked to intestinal dysbiosis, barrier disruption, and microbial translocation. Extracellular vesicles (EVs)—host small EVs, tumor-derived EVs, and bacterial extracellular vesicles (including outer membrane vesicles)—may provide a mechanistically plausible, information-dense route by which these domains could be coupled. Here, we synthesize emerging evidence suggesting that cross-kingdom EV signaling may operate as a vesicular ecosystem spanning gut lumen, mucosa, circulation, and peripheral organs. We propose the “vesicular intersection layer” as a unifying framework for how heterogeneous EV cargos converge on shared host decoding hubs (e.g., pattern-recognition receptors and stress-response pathways) to potentially contribute to muscle catabolism. We critically evaluate what is known—and what remains unproven—about EV biogenesis, trafficking, and causal mechanisms in CRC cachexia, highlight methodological constraints in microbial EV isolation and attribution, and outline minimum evidentiary standards for cross-kingdom claims. Finally, we translate the framework into actionable hypotheses for EV-informed endotyping, biomarker development (including stool EV assays), and therapeutic strategies targeting shared signaling nodes (e.g., TLR4–p38) and endocrine mediators that are predominantly soluble but may be fractionally vesicle-associated (e.g., GDF15). By reframing CRC cachexia as an emergent property of tumor–host–microbiota vesicular communication, this review provides a roadmap for mechanistic studies and clinically tractable interventions. Full article

Background: Sepsis-induced organ dysfunction poses a significant clinical challenge with limited therapeutic options. This study investigated the therapeutic potential of the glucagon-like peptide-1 receptor agonist (GLP-1RA) liraglutide in sepsis and its underlying mechanisms, focusing on modulation of the gut microbiota-derived metabolome. Methods: Public transcriptomic data analysis identified overlapping targets between liraglutide and sepsis-related genes. In a murine cecal ligation and puncture (CLP) model, liraglutide treatment was evaluated for its effects on survival, systemic inflammation, and organ injury. The gut microbiota composition and fecal metabolome were assessed via 16S rRNA sequencing and UPLC-MS. We also measured plasma GLP-1 in sepsis patients and examined the microbiota-dependency of liraglutide’s effects using antibiotic-depleted mice and fecal microbiota transplantation (FMT) from liraglutide-treated mice. Additionally, citrulline, a key identified metabolite, was functionally validated both in vitro and in a clinical cohort. Results: Liraglutide significantly improved survival, reduced pro-inflammatory cytokines, and alleviated lung, liver, and colon damage in septic mice. It partially restored sepsis-induced gut dysbiosis and modulating associated metabolites, including increasing citrulline. The survival benefit of liraglutide was abolished in microbiota-depleted mice, while FMT from liraglutide-treated mice conferred protection against sepsis, confirming the gut microbiota as a critical mediator. Furthermore, citrulline exhibited direct anti-inflammatory properties in cellular assays, and its plasma levels were negatively correlated with sepsis biomarkers (PCT and CRP) in patients. Conclusions: Taken together, our findings indicate that liraglutide mitigates sepsis by modulating the gut microbiota and regulating associated metabolic pathways. Citrulline may represent a potential microbial mediator or exploratory biomarker within this axis, warranting further mechanistic investigation. Full article

Gastric cancer (GC), often diagnosed at advanced or metastatic stages, remains a significant clinical challenge requiring novel biomarkers for early detection, risk stratification, and effective, personalized treatment optimization. Emerging evidence underscores a strong association between gut microbiome dysbiosis and GC initiation, progression, and therapeutic outcomes. This review explores the potential of the advanced/metastatic gastric microbiome as a source of diagnostic and targetable biomarkers and its role in modulating responses to immunotherapy. Although Helicobacter pylori (H. pylori) is the most significant risk factor for GC, several other gastrointestinal taxa—including Fusobacterium nucleatum (F. nucleatum)—have been implicated in advanced GC (AGC). At its inception, microbial dysbiosis contributes to chronic inflammation and immune evasion, thereby influencing tumor behavior and treatment efficacy. Integrating microbiome-based biomarkers into risk stratification, GC staging, and targetable treatment frameworks may enhance early detection, inform immunotherapy strategies, and improve patient-specific treatment responses. Bifidobacterium and Lactobacillus rhamnosus GG have the potential to change the immunotherapy framework with their direct influence on dendritic cell (DC) and cytotoxic T cell (CTL) activity. However, clinical translation is impeded by methodological heterogeneity, causality limitations, and a lack of clinical trials. Nonetheless, the integration of microbiome profiling and the development of therapeutic microbiome modulation strategies, such as personalized probiotics regimens and fecal microbiota transplantation, hold substantial potential for improving clinical outcomes and reducing treatment-related toxicity in GC management. Full article

Chronic Kidney Disease (CKD) and Colorectal Cancer (CRC) share a profound epidemiological link, supported by Mendelian randomization studies suggesting causality. This review articulates a refined Gut–Kidney Axis, focusing on the pathophysiology of indole-derived uremic toxins. CKD-induced dysbiosis drives hepatic synthesis and systemic accumulation of indoxyl sulfate, which is proposed to promote carcinogenesis via Aryl Hydrocarbon Receptor (AhR) and Akt signaling, ultimately upregulating c-Myc and EGFR. We propose a two-compartment model: while systemic indoxyl sulfate reflects the total gut indole pool (mainly from planktonic bacteria), adherent bacteria like Fusobacterium nucleatum may create high-concentration indole hotspots within the tumor microenvironment. Clinically, we advocate for protein-independent DNA methylation biomarkers (SEPT9, SDC2) to avoid renal confounding. Furthermore, we propose a novel diagnostic panel integrating serum indoxyl sulfate (systemic load) and urinary indoxyl sulfate (gut production) to guide therapy. Therapeutically, targeting upstream drivers (AhR/Akt) may bypass resistance to anti-EGFR therapies in KRAS-mutated tumors. We also discuss the repurposing of the oral adsorbent AST-120 and emerging bacteriophage therapies as strategies to disrupt this oncogenic axis. This review offers a comprehensive framework for stratified management of CKD-associated CRC. 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

In patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT), emerging evidence suggests that the oral microbiota may serve as a predictive biomarker. We conducted a systematic review to provide a critical overview of oral microbiota research in the allo-HSCT setting. We searched PubMed, Embase, and Web of Science from inception to December 2025 to identify studies assessing the oral microbiota in allo-HSCT settings. We included all articles reporting detailed data on the oral microbiota in this context and conducted a qualitative synthesis. Risk of bias was assessed using the JBI critical appraisal tools. From 8160 initially identified records, 35 studies evaluating the oral microbiota in 1964 allo-HSCT patients were included. Of these, 27 studies (77%) assessed temporal oral microbiota dynamics and reported dysbiosis in the early post-transplantation period, followed by gradual recovery. Additionally, 27 studies (77%) evaluated the prognostic value of the oral microbiota, identifying associations with key clinical outcomes such as oral mucositis, overall survival, and graft-versus-host disease. Finally, substantial methodological heterogeneity was observed across studies, including differences in sampling techniques, sampling timepoints, and analytical strategies. This systematic review highlights the prognostic and therapeutic potential of the oral microbiota in allo-HSCT and underscores the need for standardized methodologies. Full article

Objective: The study aims to evaluate the diagnostic and prognostic efficacy of gut-derived trimethylamine N-oxide (TMAO) as a molecular biomarker for heart failure (HF) in comparison to the N-terminal pro-B-type natriuretic peptide. Background: The clinical value of N-terminal pro-B-type natriuretic peptide (NT-proBNP) is frequently affected by non-cardiac physiological variables, including adiposity, advanced age, and renal clearance rates. Consequently, there is a compelling need for additional biomarkers. This analysis investigates TMAO as a critical mediator within the gut–heart axis, reflecting systemic inflammation and myocardial fibrosis secondary to intestinal dysbiosis. Methods: A comprehensive literature search was conducted using PubMed. Keywords such as “trimethylamine N-oxide”, “heart failure”, “heart failure with preserved ejection fraction” and “N-terminal pro-B-type natriuretic peptide” were used. The inclusion criteria comprised original research and literature reviews describing the pathophysiological mechanisms and clinical utility of TMAO in the context of HF diagnosis and prognosis. Results: The analyzed literature suggests that TMAO functions as an independent predictor of major adverse cardiovascular events, correlating with all-cause mortality and rehospitalization risk across all HF phenotypes. Furthermore, data indicate that using TMAO alongside NT-proBNP measurements may predict patient risk more accurately, particularly in patients where natriuretic peptide interpretation is traditionally obscured by comorbidities such as diabetes mellitus and chronic kidney disease. Conclusions: Although NT-proBNP remains the gold standard for acute diagnosis, TMAO provides significant value for long-term clinical management. By serving as a metabolic–inflammatory indicator, TMAO complements standard diagnostic panels, offering deeper insights into the prognostic trajectory and the underlying intestinal barrier integrity of patients with HF. Full article

Diet plays a central role in shaping the composition and metabolic activity of the oral microbiota, thereby influencing both oral and systemic health. Disturbances in this delicate host–microbe balance, triggered by dietary factors, smoking, poor oral hygiene, or antibiotic use, can lead to microbial dysbiosis and increase the risk of oral diseases such as periodontitis, as well as chronic systemic disorders including diabetes, cardiovascular disease, Alzheimer’s disease, and certain cancers. Among dietary contaminants, exposure to toxic heavy metals such as cadmium (Cd), lead (Pb), mercury (Hg), nickel (Ni), and arsenic (As) represents an underrecognized modifier of the oral microbial ecosystem. Even at low concentrations, these elements can disrupt microbial diversity, promote inflammation, and impair metabolic homeostasis. Saliva has recently emerged as a promising, non-invasive biofluid for monitoring nutritional status and early metabolic alterations induced by diet and environmental exposures. Salivary biomarkers, including metabolites, trace elements, and microbial signatures, offer potential for assessing the combined effects of diet, microbiota, and toxicant exposure. This review synthesizes current evidence on how diet influences the oral microbiota and modulates susceptibility to heavy metal toxicity. It also examines the potential of salivary biomarkers as integrative indicators of nutritional status and metabolic health, highlights methodological challenges limiting their validation, and outlines future research directions for developing saliva-based tools in personalized nutrition and precision health. Full article

Neuroblastoma is a highly aggressive pediatric malignancy originating from neural crest progenitor cells, predominantly in the adrenal medulla. Amplification of the MYCN oncogene occurs in 20–30% of all neuroblastoma cases and approximately 50% of high-risk tumors, strongly correlating with poor prognosis, relapse, and multidrug resistance. MYCN-driven oncogenesis promotes tumor progression by suppressing apoptotic signaling and enhancing survival pathways, including autophagy—a key mechanism underlying resistance to chemotherapy and immunotherapy. This review examines current therapeutic strategies and resistance mechanisms in MYCN-amplified neuroblastoma, while introducing emerging approaches utilizing exosomes as precision drug delivery systems. Exosomes, nanoscale extracellular vesicles secreted by the tumor cells, exhibit natural tropism and can be engineered to selectively target neuroblastoma-specific biomarkers such as glypican-2 (GPC2), which is highly expressed in MYCN-amplified tumors. Leveraging this property, neuroblastoma-derived exosomes can be purified, modified, and loaded with small interfering RNA (siRNA) to silence MYCN expression, combined with chloroquine—an FDA-approved autophagy inhibitor—to simultaneously inhibit autophagy and induce apoptotic signaling. This dual-targeted approach aims to overcome drug resistance, reduce off-target toxicity, and enhance therapeutic efficacy through exosome-mediated specificity. Furthermore, gut dysbiosis has emerged as a critical factor influencing tumor progression and diminishing treatment efficacy in MYCN-amplified neuroblastoma. We propose integrating microbiota-derived exosomes engineered to deliver anti-inflammatory microRNAs (miRNAs) to the gut mucosa, restoring eubiosis and potentiating systemic anti-tumor responses. Collectively, exosome-based strategies represent a paradigm shift in formulating combination therapies, offering a multifaceted approach to target MYCN amplification, inhibit autophagy, induce apoptosis, and modulate the tumor-microbiome axis. These innovations hold significant promise for improving clinical outcomes in high-risk MYCN-amplified neuroblastoma patients. Full article

Background/Objectives: Hepatocellular carcinoma (HCC) is one of the most common causes of cancer and cancer-related death worldwide. Beyond the well-known factors influencing the risk of HCC, experimental data from animal models and observational human studies support a significant role of the gut microbiota (GM) in HCC initiation and progression. Dysbiosis and increased intestinal permeability synergistically disrupt the ‘gut–liver axis,’ exposing the liver to bacterial metabolites and microbial-associated molecular patterns, thereby contributing to hepatocarcinogenesis. While these findings have expanded our understanding of HCC pathogenesis, a critical translational gap persists as most data derive from preclinical settings, with limited validation in large-scale clinical studies. Methods: This narrative review aimed to contextualise the current evidence on the GM-HCC axis and its clinical translatability. A literature search was conducted in PubMed/MEDLINE, Scopus, and Web of Science up to July 2025 using Medical Subject Headings and related keywords, including HCC, GM, dysbiosis, intestinal permeability, gut–liver axis, microbial metabolites, inflammation/immune modulation, and microbiota-targeted interventions (probiotics, antibiotics, and faecal microbiota transplantation). Reference lists of relevant articles were also screened to identify additional studies. Results: Preclinical models consistently indicate that dysbiosis and impaired gut barrier function can promote hepatic inflammation, immune dysregulation, and pro-tumorigenic signalling through microbe-derived products and metabolite perturbations, supporting a contributory role of the GM in hepatocarcinogenesis. In humans, HCC and advanced chronic liver disease are associated with altered microbial composition and function, increased markers of intestinal permeability, and changes in bile acid and other metabolite profiles; however, reported signatures are heterogeneous across cohorts and analytical platforms. Conclusions: The GM is a biologically plausible and experimentally supported contributor to HCC initiation and progression, with potential for biomarker development and therapeutic targeting. However, clinical translation is limited by predominantly preclinical/associative evidence, interindividual variability, and non-standardised microbiome methods. Large longitudinal studies and adequately powered randomised trials are needed to establish causality, validate biomarkers, and determine whether GM modulation improves HCC prevention, detection, stratification, or outcomes. Full article

Adiposity-Based Chronic Disease (ABCD) is known to increase the risk of aggressive prostate cancer (PCa), recurrent disease after treatment for localized PCa, and PCa mortality. A key mechanistic link contributing to this enhanced risk is chronic inflammation originating from excess white visceral adipose tissue (WAT; VAT) and periprostatic adipose tissue (ppWAT). Contributing to systemic inflammation is gut dysbiosis, which itself may be caused by ABCD as well as background local inflammation (prostatitis), which is common in aging men and may be exacerbated by the urinary microbiome. Investigating the molecular biology driving inflammation and its association with increased PCa risk, a recent paper applied a network and gene set enrichment to adipokine drivers in the ABCD-PCa network. It found prominent roles for MCP-1, IL-1β, and CXCL-1 in addition to confirming the importance of exposure to lipopolysaccharides and bacterial components, corroborating the role of gut dysbiosis. To further unravel the mechanistic links between ABCD and PCa risk, this critical review will discuss the current literature on prominent inflammatory signaling pathways activated in ABCD; the influence of gut dysbiosis, the urinary microbiome, and chronic prostatitis; and current hypotheses on how these domains may result in the development of aggressive PCa over a man’s life. Moreover, we performed a novel pathway enrichment analysis to further evaluate the associations between ABCD, PCa risk, gut dysbiosis, and the prostate microbiome, the results of which were partitioned into extracellular and intracellular signaling pathways. In the extracellular space, novel mechanistic links between gut dysbiosis and MCP-1, IL-1β, CXCL1, and leptin via bacterial pathogen signaling and the intestinal immune network (for IgA production), crucial for gut immune homeostasis, were found. Within the intracellular space, there were downstream signals activating chemokine and type 2 interferon pathways, focal adhesion PI3K/Akt/mTOR pathways, as well as the JAK/STAT, NF-κB, and PI3K/Akt pathways. Overall, these findings point to an emerging molecular pathway for PCa oncogenesis influenced by ABCD, gut dysbiosis, and inflammation, and further research, possibly with lifestyle program-based clinical trials, may discover novel biomarker panels and molecular targeted therapies for the prevention and treatment of PCa. Full article

Background: Early identification of irreversible pulmonary vascular remodeling in congenital heart disease-associated pulmonary arterial hypertension (C-PAH) is critical for optimizing surgical timing. Current noninvasive diagnostic methods are inadequate, and the lung microbiome and metabolome may provide novel insights into disease progression. Methods: We analyzed bronchoalveolar lavage fluid (BALF) from 47 children, including those with C-PAH (n = 15), CHD without PAH (C-NPAH, n = 16), and healthy controls (n = 16), using 16S rRNA gene sequencing and untargeted metabolomics. Differential microbial taxa and metabolites were identified, and their interactions with clinical indicators were assessed via Random Forest (RF) and Mediation Analysis. Results: C-PAH patients exhibited airway microbial dysbiosis, characterized by an elevated Firmicutes/Bacteroidetes (F/B) ratio and increased abundance of g_Lactobacillus. Metabolomic profiling revealed 88 differential metabolites between C-PAH and controls, and 3 between C-PAH and C-NPAH. N1-methylnicotinamide (MNAM) and 2-piperidone emerged as potential biomarkers. Mediation analysis showed that g_Eikenella influenced PAH indirectly through 2-piperidone (β = −0.376, p = 0.026), indicating a microbe–metabolite–host interaction. Conclusions: Integrative microbiome–metabolome profiling of BALF reveals potential biomarkers for C-PAH. These findings provide exploratory evidence that microbial and metabolic biomarkers, particularly 2-piperidone and MNAM, hold potential for the early, noninvasive identification of irreversible pulmonary vascular remodeling, but require further validation in independent cohorts. Full article

Background/Objectives: The study investigated the potential of mixed fruits and berries (MFB) as a dietary intervention to mitigate cafeteria (CAF) diet-induced gut microbiome dysbiosis and hepatic dysfunction associated with metabolic syndrome and steatohepatitis (MASH) in an adolescent rat model. Methods: Forty-eight adolescent male Sprague-Dawley rats (n = 3 cages per group (two rats per cage)) were divided into eight experimental groups, where NC received the normal AIN-93G basal diet, PC received the CAF diet and normal AIN-93G basal diet, T₁ and T₂ received MFB supplementation (3% and 6% levels) without CAF exposure, P₁ and P₂ received a MFB (3% and 6% levels) supplementation initiated at the onset of CAF feeding, and I₁ and I₂ received MFB supplementation initiated 2 weeks after CAF feeding. After 6 weeks, cecal 16S rRNA, hepatic histopathology, Oil Red O staining, and metabolic dysfunction-associated steatotic liver disease (MASLD)-related biomarkers (liver enzymes, alanine aminotransferase (ALT), and aspartate aminotransferase (AST)) were analyzed. Results: AST: ALT ratio was the highest in the PC group (3.63, p < 0.05) compared to the MFB groups. Oil Red O staining showed lower hepatic lipid accumulation, and histological analysis demonstrated a marked reduction in portal inflammatory cell infiltration in MFB. Alpha diversity (Simpson Index) decreased in PC (Kruskal–Wallis, p = 0.043). CAF increased Lactobacillus johnsonii (+75%, p < 0.05), while reducing L. murinus and L. intestinalis (~90%, p < 0.05). MFB supplementation restored Bifidobacterium Pseudolongum and increased Akkermansia muciniphila levels in the P₂, I₁, and I₂ groups (~20-fold, p < 0.05). Bacteroides dorei was present in all groups except the PC group. These bacteria presented a positive correlation with key SCFAs. Conclusions: The results from this study indicated that MFB supplementation modulated gut microbiota composition and enhanced SCFA production, thereby strengthening intestinal barrier integrity and reducing gut-derived inflammation. Collectively, these effects attenuated hepatic lipid accumulation and inflammation, highlighting the potential of MFB to restore gut–liver axis homeostasis disrupted by CAF-induced dysbiosis in adolescent rats. Full article