Search Results (307)

Low-dose carrot rhamnogalacturonan-I (cRG-I) has shown consistent modulatory effects on the gut microbiota and immune function in humans. In this study we investigated its effects on the microbial composition and metabolite production of the gut microbiota of small (5–10 kg), medium-sized (10–27 kg), and large (27–45 kg) dogs, using inulin and xanthan as comparators. Fecal samples from six dogs of each size group were evaluated. Overall microbiome composition, assessed using metagenomic sequencing, was shown to be driven mostly by dog size and not treatment. There was a clear segregation in the metabolic profile of the gut microbiota of small dogs versus medium-sized and large dogs. The fermentation of cRG-I specifically increased the levels of acetate/propionate-producing Phocaeicola vulgatus. cRG-I and inulin were fermented by all donors, while xanthan fermentation was donor-dependent. cRG-I and inulin increased acetate and propionate levels. The responses of the gut microbiota of different sized dogs to cRG-I were generally consistent across donors, and interindividual differences were reduced. This, together with the significant increase in P. vulgatus during fermentation in both this study and an earlier human ex vivo study, suggests that this abundant and prevalent commensal species has a core capacity to selectively utilize cRG-I. Full article

Endometriosis is a chronic inflammatory condition affecting approximately 10% of women of reproductive age, characterized by pelvic pain, dysmenorrhea, and infertility. Emerging evidence suggests a potential link between gut microbiota dysbiosis and endometriosis pathogenesis, mediated through hormonal regulation, immune modulation, and systemic inflammation. Dienogest (DNG) is widely used for endometriosis management, but its effects on gut microbiota remain underexplored. This study investigates the impact of DNG on gut microbial composition in endometriosis patients, aiming to elucidate its therapeutic mechanisms beyond hormonal modulation. DNG therapy led to a significant reduction in the Bacillota/Bacteroidota ratio (p = 0.0421), driven by decreased Staphylococcus spp. (p = 0.0244) and increased commensal bacteria such as Lactobacillus spp. and Collinsella aerofaciens (p = 0.049). Species richness and alpha diversity indices showed a non-significant upward trend. Notably, C. aerofaciens, a butyrate producer linked to gut barrier integrity, was detected twice as frequently during therapy. The study also observed reductions in facultative anaerobes like Enterococcus spp. and a trend toward higher titers of beneficial Bacteroidota. This study provides the first evidence that DNG therapy modulates gut microbiota in endometriosis patients, favoring a composition associated with anti-inflammatory and barrier-protective effects. The observed shifts—reduced opportunistic pathogens and increased symbionts—suggest a novel mechanism for DNG’s efficacy, potentially involving the microbial regulation of estrogen metabolism and immune responses. Full article

Konjac glucomannan (KGM) is a natural polysaccharide polymer. It is degraded by gut microbiota-derived β-mannanase into small-molecule nutrients, which exert diverse physiological regulatory effects. As a prebiotic, KGM modulates gut microbiota composition. It selectively fosters the proliferation of beneficial commensals and suppresses potential pathogens, thereby alleviating microbiota-related disorders. Moreover, microbiota fermentation of KGM produces metabolites. Short-chain fatty acids (SCFAs) are particularly notable among these metabolites. They exert multifaceted beneficial effects, including metabolic regulation, intestinal barrier strengthening, and neuroprotective functions. These effects are mediated through inhibition of inflammatory pathways (e.g., NF-κB, MAPK), modulation of lipid metabolism genes (e.g., CD36), and regulation of neurotransmitters (e.g., GABA, 5-HT). This highlights KGM’s therapeutic potential for metabolic, inflammatory, and neurodegenerative diseases. Current clinical use is limited by dose-dependent adverse effects and interindividual response variability, which stem from different microbial communities. This necessitates personalized dosage strategies. Despite these limitations, KGM as a prebiotic polysaccharide exhibits multifaceted bioactivity. Current evidence suggests its potential to synergistically modulate metabolic pathways, gut microbiota composition, immune cell signaling, and neuroendocrine interactions. This highlights its promise for developing novel therapeutic interventions. Full article

Disruption of the microbiota resulting in pathogenicity is known as dysbiosis and is key in the pathogenesis of inflammatory bowel disease [IBD]. The microbiome of patients with IBD is characterized by depletion of commensal bacteria, in particular Bacteroidetes and the Lachnospiraceae subgroup of Firmicutes, and by the concomitant increase in Proteobacteria and the Bacillus subgroup of Firmicutes. These changes reflect a decrease in microbial diversity with a concomitant decrease in health-promoting bacteria like Faecalibacterium and Roseburia. Treatment with biologic agents has changed the natural course of disease, improving patient outcomes. Changes in gut microbiota occur under treatment with biologic agents and act towards reversal of dysbiosis. These changes are more striking in patients achieving remission and specific gut microbiota signatures may be predictive of treatment response and a step towards precision medicine, since, despite advances in medical treatment, some patients are at risk of surgery and subsequent complications such as anastomotic leakage. This review summarizes current available evidence on the interplay of gut microbiota and biologic agents, surgery, and surgical complications in patients with IBD. Full article

Due to the growth in the application of antibacterial nanomaterials (NMs), there is an increased potential for ingestion by humans. Evidence shows that NMs can induce dysbiosis in the gut microbiota in vivo. However, in vitro investigation of the antibacterial activity of NMs on gut-relevant, commensal bacteria has been neglected, with studies predominantly assessing NM toxicity against pathogenic bacteria. The current study investigates the antibacterial activity of copper oxide (CuO) NMs to Escherichia coli K12, Enterococcus faecalis, and Lactobacillus casei using a combination of approaches and evaluates the importance of reactive oxygen species (ROS) production as a mechanism of toxicity. The impact of CuO NMs (100, 200, and 300 μg/mL) on the growth and viability of bacterial strains was assessed via plate counts, optical density (OD) measurements, well and disc diffusion assays, and live/dead fluorescent imaging. CuO NMs reduced the viability of all bacteria in a concentration-dependent manner in all assays except the diffusion assays. The most sensitive methods were OD measurements and plate counts. The sensitivity of bacterial strains varied depending on the method, but overall, the results suggest that E. coli K12 is the most sensitive to CuO NM toxicity. The production of ROS by all bacterial strains was observed via DCFH-DA fluorescent imaging following exposure to CuO NMs (300 μg/mL). Overall, the data suggests that CuO NMs have antibacterial activity against gut-relevant bacteria, with evidence that NM-mediated ROS production may contribute to reductions in bacterial viability. Our findings suggest that the use of a combination of assays provides a robust assessment of the antibacterial properties of ingested NMs, and in particular, it is recommended that plate counts and OD measurements be prioritised in the future when screening the antibacterial properties of NMs. Full article

Colorectal cancer (CRC) is a multifactorial disease increasingly recognized for its complex interplay with the gut microbiota. The disruption of microbial homeostasis—dysbiosis—has profound implications for intestinal barrier integrity and host immune function. Pathogenic bacterial species such as Fusobacterium nucleatum, Escherichia coli harboring polyketide synthase (pks) island, and enterotoxigenic Bacteroides fragilis are implicated in CRC through mechanisms involving mucosal inflammation, epithelial barrier disruption, and immune evasion. These pathogens promote pro-tumorigenic inflammation, enhance DNA damage, and suppress effective anti-tumor immunity. Conversely, commensal and probiotic bacteria, notably Lactobacillus and Bifidobacterium species, exert protective effects by preserving epithelial barrier function and priming host immune responses. These beneficial microbes can promote the maturation of dendritic cells, stimulate CD8⁺ T cell cytotoxicity, and modulate regulatory T cell populations, thereby enhancing anti-tumor immunity. The dichotomous role of the microbiota underscores its potential as both a biomarker and a therapeutic target in CRC. Recent advances in studies have explored microbiota-modulating strategies—ranging from dietary interventions and prebiotics to fecal microbiota transplantation (FMT) and microbial consortia—as adjuncts to conventional therapies. Moreover, the composition of the gut microbiome has been shown to influence the responses to immunotherapy and chemotherapy, raising the possibility of microbiome-informed precision oncology therapy. This review synthesizes the current findings on the pathogenic and protective roles of bacteria in CRC and evaluates the translational potential of microbiome-based interventions in shaping future therapeutic paradigms. Full article

The intestinal microbiota of fish is predominantly composed of prokaryotic microorganisms, with research historically focused on bacteria. In contrast, the role of microeukaryotic organisms in the fish gut remains largely unexplored. This review synthesizes current knowledge on the diversity, ecology, and potential functions of intestinal microeukaryotes, particularly fungi and protozoans, in teleost fish. Fungi, especially Ascomycota and Basidiomycota phyla members, are consistently identified across species and may contribute to digestion, immune modulation, and microbial homeostasis. Protists, though often viewed as pathogens, also exhibit potential commensal or immunoregulatory roles, including the modulation of bacterial communities through grazing. Other eukaryotic taxa, including metazoan parasites, microalgae, and zooplankton, are commonly found as transient or diet-derived members of the gut ecosystem. While many of these organisms remain poorly characterized, emerging evidence suggests they may play essential roles in host physiology and microbial balance. The review highlights the need for improved detection methodologies, functional studies using gnotobiotic and in vitro models, and multi-kingdom approaches to uncover fish gut microeukaryotes’ ecological and biotechnological potential. Full article

Background/Objectives: Lactobacillus delbrueckii subsp. lactis CKDB001 (LL) has demonstrated anti-inflammatory, antioxidant, and lipid-regulatory effects in vitro and in vivo, including attenuation of hepatic steatosis and modulation of lipid metabolism. Given the known interactions between host metabolism and gut microbiota, these findings suggest a potential role for LL in modulating microbial composition under conditions of diet-induced obesity. This study aimed to investigate the microbiome-related effects of LL using an established murine model. To evaluate the effect of LL supplementation on gut microbial composition and predict microbial metabolic functions in mice with high-fat diet-induced obesity. Methods: Male C57BL/6J mice were fed a high-fat diet and administered LL orally for 12 weeks. Fecal samples were collected and analyzed using 16S rRNA gene sequencing. Microbial taxonomic profiles were assessed using linear discriminant analysis effect size, and functional predictions were performed using PICRUSt2. Results: LL supplementation significantly altered the gut microbiota by increasing the relative abundance of Lactobacillus and other commensal taxa while reducing the prevalence of pro-inflammatory genera such as Alistipes and Bilophila. Functional prediction analysis revealed a downregulation of lipopolysaccharide and ADP-L-glycero-β-D-manno-heptose biosynthesis pathways. Microbial functions associated with carbohydrate metabolism and short-chain fatty acid production were enriched in the LL-treated group. Conclusions: LL modulated gut microbial composition and suppressed pro-inflammatory microbial pathways while enhancing beneficial metabolic functions in high-fat diet-fed mice. These findings support the potential of LL as a safe and effective microbiota-targeted probiotic for managing obesity-related metabolic disorders. Full article

Methylglyoxal (MGO) is a highly reactive dicarbonyl associated with oxidative stress, inflammation, and chronic diseases, particularly diabetic vascular complications and atherosclerosis through the formation of advanced glycation end products (AGEs). In the setting of human/host diseases, the formation of MGO has mainly been considered as the byproduct of glycolysis. Gut microbes play an important role in the development of cardiometabolic diseases. Here, we discuss a possibility that gut microbes can modulate the MGO pool within the host through (i) the alternation of the host metabolism, and (ii) direct MGO synthesis and/or detoxification by human commensal microorganisms. We also explore how dietary MGO impacts the composition of the gut microbiota and their potential role in modulating host health. This paradigm is highly innovative, with the current literature providing observations supporting this concept. Targeting the gut microbiome is emerging as an approach for treating cardiometabolic diseases through dietary, pre-, pro-, and postbiotic interventions, faecal microbiota transplantations, and the use of small molecule inhibitors of microbial enzymes. This can be a novel strategy to reduce MGO stress in the setting of cardiometabolic diseases and lowering the burden of diabetic complications and cardiovascular disease. Full article

Vestibulodynia is vulvodynia localized to the vulvar vestibule and is a chronic disease defined as vulvar pain of at least three months’ duration, without a defined cause, that severely affects women’s health and quality of life with limited treatment options. We collected stool and vaginal samples from 30 women affected by vestibulodynia and 27 healthy women. Bacterial gut and vaginal microbiomes were characterized by amplicon sequencing, and compositional and functional differences between the control and the patient groups were assessed. No differences in vaginal or fecal alpha and beta diversity were found, but vaginal microbiota of patients was found to be associated with Lactobacillus iners. Moreover, the relative abundance of L. iners negatively correlated with the relative abundance of L. crispatus, and positive correlations between commensals and pathobionts were found in the vestibulodynia vaginal microbiota but not in the healthy controls. The bacterial functions and contributors were defined in the study groups for the fecal and vaginal microbiota. Our results portrayed the vaginal microbiome of patients with vestibulodynia as potentially not as efficient at living in an anaerobic environment as the healthy microbiome is and too inclined to acidify this environment, exposing it to the risk of developing other ailments. Full article

Prebiotic oligosaccharides have attracted significant interest in dermatology and skin health due to their ability to modulate the skin microbiome and microbiota–host interactions. This review offers a novel dual perspective, systematically examining the benefits of both oral intake and topical application of prebiotic oligosaccharides, including well-established prebiotics (e.g., human milk oligosaccharides, galacto- and fructo-oligosaccharides) and emerging prebiotic candidates (e.g., gluco-oligosaccharides, chitosan-oligosaccharides, agaro-oligosaccharides). First, cutting-edge synthetic processes for producing diverse oligosaccharides and their structural chemistry are introduced. Then, we discuss in vitro studies demonstrating their efficacy in promoting skin commensals, inhibiting pathogens, and conferring protective effects, such as antioxidant, anti-inflammatory, anti-melanogenic, and wound-healing properties. Furthermore, we emphasize in vivo animal studies and clinical trials revealing that prebiotic oligosaccharides, administered orally or topically, alleviate atopic dermatitis, enhance skin hydration, attenuate acne, and protect against photo-aging by modulating skin–gut microbiota and immune responses. Mechanistically, we integrate genetic and molecular insights to elucidate how oligosaccharides mediate these benefits, including gut–skin axis crosstalk, immune regulation, and microbial metabolite signaling. Finally, we highlight current commercial applications of oligosaccharides in cosmetic formulations while addressing scientific and practical challenges, such as structure–function relationships, clinical scalability, and regulatory considerations. This review bridges mechanistic understanding with practical applications, offering a comprehensive resource for advancing prebiotic oligosaccharides-based skincare therapies. Full article

Cancer cachexia is a multi-organ and multifactorial syndrome characterized by muscle wasting (with or without adipose tissue loss) and systemic inflammation in patients with advanced malignancies. Gut microbiota dysbiosis, particularly the depletion of short-chain fatty acid (SCFA)-producing bacteria, may contribute to the progression of cancer cachexia. Studies in both murine models and humans consistently associate cachexia with a decline in SCFA-producing gut microbiota commensals and an overgrowth of pro-inflammatory pathobionts. These microbial imbalances may lead to reduced levels of SCFAs and branched-chain amino acids (BCAAs) and alter the normal bile acid profile. BCAAs and the maintenance of a normal bile acid profile are associated with muscle synthesis and decreased breakdown. While SCFAs (acetate, propionate, and butyrate), contribute to intestinal barrier integrity and immune regulation. SCFA depletion may increase gut permeability, allowing bacterial endotoxins, such as lipopolysaccharide (LPS), to enter the bloodstream. This may lead to chronic inflammation, muscle catabolism, and impairment of anabolic pathways. Interventions targeting gut microbiota in preclinical models have mitigated inflammation and muscle loss. While clinical data are limited, it suggests an improvement in immune functions and better tolerance to anticancer therapies. Current evidence is predominantly derived from cross-sectional studies suggesting associations without causality. Thus, future longitudinal studies are needed to identify biomarkers and optimize personalized therapy. Full article

Background: Crohn’s disease (CD) is an inflammatory bowel disease in which there is an alteration in the homeostasis and functionality of the intestinal mucosa accompanied by a dysbiosis of the commensal microbiota. The analysis of different dietary strategies to achieve CD remission and reduce gastrointestinal symptoms concludes that it is necessary to restrict the intake of ultra-processed products and to promote the consumption of those with anti-inflammatory effects that improve intestinal permeability and dysbiosis. Methods: Based on previous studies conducted in other cohorts, mainly pediatric, we propose an experimental, prospective, randomized study in patients with active CD who do not show improvement with conventional pharmacological treatment. The control group will receive standard nutritional recommendations while the intervention group will be prescribed an exclusion diet supplemented with enteral nutrition. Results: Patients in the intervention group are expected to exhibit increased lean body mass and reduced visceral fat, as measured by bioelectrical impedance analysis (BIA), alongside higher rates of clinical remission (CDAI), decreased inflammatory markers, and improved gut microbiota composition. Additionally, improvements in health-related quality of life are anticipated, as assessed by validated questionnaires. Conclusions: In the present project, we plan to conduct a detailed study to determine the potential of the exclusion diet for the treatment and remission of CD in adult patients, with the hypothesis that this nutritional intervention will be able to modify and improve intestinal dysbiosis, inflammatory status, and clinical and body composition markers in these patients. Full article

Background: Cow-milk-induced allergic proctocolitis (CMIAP) is a non-IgE-mediated food hypersensitivity that often resolves spontaneously but may predispose infants to IgE-mediated allergies and eosinophilic gastrointestinal disorders. Understanding its pathophysiology is crucial for microbiota-based interventions. Methods: We enrolled 32 exclusively breastfed infants—16 with confirmed cases of CMIAP and 16 age-matched healthy controls. The cohorts were sex-balanced (8 F/8 M), term-born (gestational age ± SD: 40 ± 1.2 vs. 39 ± 1.3 weeks), vaginally delivered, and sampled at a mean age of 2.0 ± 0.44 months (range 1.5–3.0) vs. 2.4 ± 0.66 months (range 1.5–3.5). Faecal samples underwent 16S rRNA gene sequencing on the Illumina NovaSeq platform, with diversity and differential abundance analyses. Results: The maternal dairy intake was similar (total dairy: 250 ± 80 vs. 240 ± 75 mL/day; yoghurt: 2.3 ± 1.0 vs. 2.5 ± 1.2 days/week; p = 0.72). Bray–Curtis dissimilarity assessments revealed distinct microbiota in infants with CMIAP. Infants with CMIAP had a lower abundance of Bifidobacterium (log₂FC−2.27; q = 0.022; ANCOM-BC), Collinsella (−29.35; padj < 0.0001; DESeq2), and Limosilactobacillus (−8.01; padj = 0.0285; DESeq2; q < 0.0001; ANCOM-BC) compared with controls. In contrast, Hungatella (+24.99; padj < 0.0001; DESeq2), Veillonella (+4.73; padj = 0.0221; DESeq2), Citrobacter (+10.44; padj = 0.0124; DESeq2), and Ruminococcus gnavus (+2.69; q < 0.0001; ANCOM–BC) were more abundant in the CMIAP group. Conclusions: Infants with CMIAP exhibit gut dysbiosis, which is characterised by the depletion of beneficial commensals and the enrichment of potential pathogens, independent of maternal dairy intake. Further studies should establish whether these microbiota alterations are causal or consequential in CMIAP. Full article

Post-COVID-19 is a chronic infection-related syndrome, including exacerbations of pre-existing or newly diagnosed conditions that have been established after the acute phase of COVID-19 and have demonstrated a wide range of systemic effects beyond the lungs. SARS-CoV-2 attaches to its receptor, angiotensin-converting enzyme 2 (ACE-2). Transmembrane serine protease 2 (TMPRSS2) facilitates viral entry and spread. ACE-2 receptors are detectable in several tissues, including the respiratory mucosa, digestive tract, heart, kidney, and brain. Several investigations have demonstrated an increase in digestive manifestations post-acute COVID-19, likely related to an alteration in the intestinal microbiota following infection. These changes can lead to a loss of species diversity, resulting in an overgrowth of opportunistic pathogens and deprivation of commensal bacteria. In this context, post-infection irritable bowel syndrome shows an increased incidence compared to controls. Growing evidence also suggests the enduring presence of SARS-CoV-2 in the gut tissue. Studies are ongoing to investigate antiviral agents that counteract prolonged COVID-19 symptoms. Therefore, the objectives of this review were to summarize the digestive manifestations, focusing on irritable bowel syndrome and therapeutic strategies. This review gives an overview of studies published in English in the last two years on the PubMed database. Full article