Gut microbiota modulates the effects of host-derived fecal microRNAs on cultured gut microbiota in mice.

BackgroundDiarrhea is one of the most common reasons for visiting canine veterinary clinics or emergency centers. Common treatment approaches include dietary modification, antibiotics, and/or probiotics, which are frequently initiated empirically. Antibiotics can have detrimental long-term effects on the gut microbiome and contribute to antimicrobial resistance, prompting a need for alternative therapies. Probiotics are a promising option; however, their strain-specific effects on the canine gut microbiome have been insufficiently characterized in vivo, particularly in dogs with diarrhea.Hypothesis/objectivesThis study aimed to evaluate tolerability and changes in fecal microbiota in dogs with diarrhea during the administration of a novel, advanced microbiome-derived probiotic (AMP) consisting of live Peptacetobacter hiranonis, Megamonas funiformis, and Enterococcus faecium, strains of which were all originally isolated from the feces of a healthy dog.AnimalsThis single-arm, prospective observational pilot study consisted of 11 client-owned adult dogs of various breeds presenting for chronic diarrhea (>5 days) with a Purina Fecal Score (PFS) between 4 and 7.MethodsTolerability of the AMP was assessed through serial clinical examinations and comparison of PFS to baseline. Dogs were classified as responders if their PFS improved to <4 by day 7, and as non-responders otherwise. Fecal samples collected at baseline, day 7, and day 56 of AMP administration underwent Illumina amplicon next-generation sequencing (NGS) of 16S rRNA gene fragments (V4 region) to assess the fecal microbiome composition and diversity in each patient.ResultsNo adverse events were noted in any dogs receiving the AMP. Clinical improvement in diarrhea was noted in eight of 11 dogs after administration of the AMP. Increases in fecal microbiome alpha-diversity were observed after 1 week of AMP administration for six out of seven long-term participants.Conclusion and clinical importanceThis pilot study indicates that the AMP was well tolerated in dogs with diarrhea, with dogs maintaining or improving clinical appearance during administration. These preliminary findings justify larger controlled studies to evaluate AMP efficacy and to explore associations between treatment, fecal microbiome changes, and clinical response.Clinical trial registrationIdentifier: VCT23005615.

Objective: To investigate the therapeutic effects of Akkermansia muciniphila (AKK) on liver injury induced by cholestasis and its mechanisms in regulating bile acid metabolism. Methods: The cholestatic mouse model was established by bile duct ligation (BDL). A total of 35 male C57BL/6J mice (8 weeks old) were divided into 5 groups using a random numder table method (7 mice per group): group A (control group), group B (BDL group), group C (BDL+AKK group), group Z (BDL+AKK+Z/E-guggulsterone group), and group G (BDL+AKK+Gly-β-muricholic acid group). Preoperative and postoperative changes in liver function and bile acid metabolism indicators was observed of mice in groups A, B, and C. The liver function and fibrosis markers were compared between groups, as well as serum, liver, and fecal total bile acid levels, fecal bile acid composition, liver histopathology, and the mRNA expression of key proteins involved in the bile acid enterohepatic circulation and the farnesoid X receptor (FXR) signaling pathway were compared. Multiple groups of data were compared using analysis of variance or nonparametric Kruskal Wallis H test. Results: Twelve days after BDL, in groups A, B, and C, mice in group C exhibited milder postoperative jaundice and their body weights on postoperative days 4-5 and 7-11 were heavier than those in group B mice (all P<0.05). The liver tissues of mice in group C were milder than those in group B in terms of appearance, histopathology, inflammation and liver fibrosis (all P<0.05). The levels of serum alanine aminotransferase, aspartate aminotransferase, as well as the expression levels of liver α-smooth muscle actin and type Ⅰ collagen, and the levels of total liver bile acid and fecal β-murine bile acid in the C group mice were all lower than those of group B mice ((46±20) vs. (90±34) U/L, (96±17) vs.(122±31) U/L, (2.01±0.11)% vs. (7.55±0.21)%, (1.92±0.10)% vs. (7.28±0.51)%, (62±14) vs. (124±39) μmol/mg, 3 052 (1 522, 6 406) vs. 14 756 (6 582, 33 474) ng/g, all P<0.05). And the mRNA expression levels of cholesterol 7α-hydroxylase and bile salt export pump of the ileum, etc. in group C mice were lower than those in group B mice (all P<0.05), while the mRNA expression levels of FXR and fibroblast growth factor 15 in the intestine were higher than those in group B mice (all P<0.05). In groups B, C, Z, and G, compared with group C, mice in groups Z and G had aggravated liver injury and fibrosis, increased total bile acid levels in the liver, and increased serum alanine aminotransferase, total bilirubin, and expression levels of liver α-smooth muscle activator protein and type I collagen (all P<0.05). There was no statistically difference in the above indicators between group Z and group G (all P<0.05). Conclusion: AKK reduces liver bile acid synthesis, regulates bile acid metabolism, alleviate liver function damage and fibrosis, and improves clinical phenotypes by activating the intestinal FXR-fibroblast growth factor 15 signaling pathway.

P1350 The involvement of intestinal microbiota and metabolites in the formation of Crohn’s disease-associated stricturing

Upon importation, laboratory mice may undergo prophylactic antiparasitic treatment during quarantine to prevent the introduction of parasites into established colonies. While quarantine protocols vary across institutions, ivermectin is commonly used, administered either orally or topically. However, the impact of these practices on the fecal microbiome remains poorly understood, raising concerns about unintended consequences for experimental outcomes. This study investigated the effects of ivermectin on fecal microbiome composition in naïve, healthy male and female C57BL/6J mice. Animals received either ivermectin-impregnated feed (12 ppm, ad libitum for 4 weeks), weekly topical ivermectin solution (2.0 mg/kg for 4 weeks), or no treatment (controls). Fecal samples were collected for 16S rRNA-based microbiome analysis before ivermectin treatment, immediately posttreatment, and 4 weeks after treatment cessation. Weekly body weights were recorded, and histopathologic evaluation of the small intestine and colon was performed at study completion. Both oral and topical ivermectin treatments resulted in significant alterations in microbiome α and β diversity at the end of treatment, with more pronounced effects observed in female mice. Some of these changes persisted for up to 4 weeks after treatment cessation. Furthermore, the findings indicate a sex-specific effect of ivermectin on specific bacterial orders, with Bacillales predominantly affected in male mice, whereas Coriobacteriales and Bacteriodales were primarily impacted in female mice. During treatment, males receiving topical ivermectin weighed significantly less than controls, while females receiving dietary ivermectin weighed significantly more. Histopathological analysis revealed no abnormalities in intestinal tissues across all groups at 4 weeks posttreatment. These findings demonstrate that ivermectin administration induces measurable and persistent changes in the fecal microbiome of healthy mice. Researchers should consider these effects when designing experiments, and institutions must weigh the benefits of colony protection against potential microbiome-related confounding variables.

BackgroundLifestyle‐based interventions can reduce 45% of dementia risk. Dietary supplementation with medium‐chain triglycerides (MCT) is a type of ketogenic diet that shows promise against Alzheimer’s disease (AD) in humans, presumably through hepatic conversion to circulating ketones. However, the physiological impacts and cellular mechanisms underlying MCT effects remain understudied, particularly in the context of AD.ObjectiveHere, we used two transgenic mouse model of AD to investigate the physiological and molecular mechanisms occurring in peripheral system upon an MCT‐enriched diet versus a classic ketogenic diet.Method3xTg‐AD, 5xFAD mice and their respective control strain mice (WT) were administered at different age and duration, a standard carbohydrate‐rich diet (Control diet, 70% carbohydrate, 20% fat, 10% protein), a similar Control diet that was supplemented with ketogenic medium‐chain triglycerides (MCT, a ketogenic substrate), or an extreme carbohydrate‐free, high fat diet (CFHF). Mice were subjected to learning/memory tests, and longitudinal monitoring of body composition, glycemia, ketonemia and fecal microbiome composition.ResultsBoth ketogenic interventions improved cognition in AD mice after 1 month of treatment. Interestingly, unlike CFHF diet, MCT diet did not induce a sustained ketosis suggesting different mechanisms. Only the MCT diet improved peripheral glucose tolerance, insulin response and reduced adiposity, while CFHF dietary challenge exacerbated AD mice metabolic defects. AD mice exhibited several microbial alterations preceding cognitive symptoms, notably increased levels of Bifidobacterium and decreased levels of Bacteroidetes. Ketogenic interventions restored the fecal microbiome composition by 50% inducing a strong depletion of Bifidobacterium.ConclusionCollectively, these findings reveal metabolism‐improving benefits of MCT in the context of Alzheimer’s disease that do not require elevated blood ketone levels and reveal potential therapeutic targets for treating AD, in the gut‐brain axis.

Fermented foods are a promising yet underexplored intervention for influencing brain function and mental health through the gut-brain axis. The objective of this study was to evaluate the impact of a dairy product fermented with probiotic bacteria on aspects of brain structure and function. In a triple-blind, randomised, placebo-controlled trial, 40 healthy women aged 18-55 years were randomised to consume either 130 g per day of a fermented probiotic yoghurt or a placebo for 8 weeks. The primary outcome was the between-group differential change from baseline to week 8 in left hippocampal metabolites, measured using magnetic resonance spectroscopy. Secondary outcomes included changes in brain structure and function, faecal microbiome composition and functional potential, mental health, gastrointestinal symptoms, memory and blood markers of oxidative stress and inflammation. There was a between-group difference in the change in average left hippocampal glutathione concentration (mean difference in change: -0.49; 95% CI -0.95 to -0.04), as well as brain volume in the hippocampus and nucleus accumbens, although these results did not withstand correction for multiple comparisons. There were between-group differences in the change in average functional connectivity between the left hippocampus and left frontal pole. There was also a significant between-group change in gut microbiome beta diversity. There were no differences in other secondary measures. This study provides preliminary evidence that a probiotic fermented dairy product can modulate hippocampal-related outcomes. ACTRN12622000622707.

Longitudinal characterization of fecal lipids in dairy heifers from birth to first calving.

The interplay between the gut microbiome (GM), plasma metabolites, and systemic sclerosis (SSc) has not been systematically studied. We hypothesized that disruption at the GM-metabolome interface contributes to the pathogenesis of SSc. This study aims to investigate the faecal microbiome composition and plasma metabolite profiles in SSc patients. To evaluate the interactions, deep shotgun metagenomic sequencing was conducted on faecal samples from 15 SSc patients and 33 healthy controls. Simultaneously, untargeted Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) metabolomic profiling was performed on plasma samples from 14 SSc patients and 30 controls. The analysis revealed significant alterations in 11 microbial species and 266 MS2-identified metabolites in SSc patients vs controls. In SSc, elevated levels of Escherichia coli, Lactobacillus mucosae, and Parabacteroides distasonis were noticed. Conversely, P. plebeius, B. hansenii, and Agathobaculum butyriciproducens were enriched in the control group. Functional predictions indicated a depletion of amino acid biosynthesis pathways, including L-isoleucine and L-methionine, in SSc patients. The metabolomic analysis demonstrated a significant reduction in lipid-like molecules and amino acid levels in SSc patients. Dysregulated pathways, such as alanine, aspartate, and glutamate metabolism, arginine and proline metabolism, and glycine, serine, and threonine metabolism, were associated with the development of SSc. Striking microbiota-metabolite correlations (168 significant associations) were identified, with disease-enriched species showing specific metabolic linkages. This study offers a comprehensive characterization of the disrupted GM-metabolite interface in SSc patients, providing new perspectives on SSc pathogenesis and potential therapeutic targets.

This study evaluated effects of Termin-8®, a formaldehyde, propionic acid, and terpene-based feed sanitizer, on the performance, health, and gut microbiome of sows and nursing piglets. One hundred and seven mixed-parity sows were allocated to control diets (n = 53) or diets containing 0.55% sanitizer (n = 54) from day 80 of gestation until approximately day 19 postpartum. Performance metrics, scours, and fecal microbiome composition via 16S rRNA sequencing were assessed. Feed sanitizer supplementation had no significant effects on sow body weight, backfat depth, feed intake, wean-to-estrus interval, litter size or weight at weaning, or piglet diarrhea incidence. However, stillborn pig weight was significantly reduced in the sanitized group (p = 0.010). Gut microbiome changed drastically from gestation to weaning in both groups (R2 > 0.20, p < 0.001), but the taxa and functions that fluctuated largely differed in each group. At weaning, both groups exhibited significantly different microbiome compositions (R2 = 0.06, p < 0.001). Feed sanitizer in sows did not influence the piglet microbiome. Supplementing formaldehyde-based feed sanitizer to sow diets did not significantly impact overall performance or health but moderately influenced sow gut microbiome composition, warranting further investigation into its potential functional implications.

Uncovering novel endocannabinoidome-gut microbiome-brain axis-based therapeutic targets in a Fragile X Syndrome mouse model.

Gut microbiota play a central role in immune defense and adapting to environmental fluctuations. Varied tits (Sittiparus varius) are socially monogamous birds with a narrow geographic distribution, whose habitat and diet undergo significant seasonal changes. We hypothesized that the diversity and composition of gut microbes in varied tits would exhibit seasonal differences, and that the relative abundance of gut microbes would be correlated with host’s immunity. To test these hypotheses, we characterized the fecal bacterial community composition of varied tits by sequencing the V3–V4 region of the 16S ribosomal RNA gene, comparing the differences in gut microbiota composition across seasons, and exploring the relationship between bacterial abundance and Immunoglobulin A (IgA) concentrations. A total of 4847 operational taxonomic units (OTUs), 40 phyla, 108 classes, 269 orders, 477 families, and 1109 genera were obtained from 16S metabarcoding. The intestinal microbiota of varied tits was dominated by the phyla Proteobacteria (35.29%), Firmicutes (26.66%), Cyanobacteria (13.99%), Actinobacteriota (9.62%) and Bacteroidota (7.32%). Significant seasonal variations in gut microbiota composition were observed, while the abundance-based coverage estimator (ACE) index of alpha diversity in spring was significantly higher than in summer, and overall community structure (beta diversity) differed markedly between winter and spring. Linear discriminant analysis effect size (LEfSe) revealed the enrichment of specific bacterial taxa in each season (LDA &gt; 4, P

Fermented probiotic dairy products with buriti and orange byproducts enhance gut and bone health.

Microbiome and metabolome changes after fecal microbiota, live-jslm, administration are associated with health-related quality of life improvements.

This systematic literature review assessed whether nutritional supplement, dietary and exercise interventions influence gut microbiota and subsequent exercise performance. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a comprehensive search was conducted across five databases (Ovid MEDLINE, EMBASE, CINAHL Complete, Web of Science and Scopus) up to February 2025. Included studies involved healthy, active adults undergoing nutrient supplementation, dietary and/or exercise interventions with a control or placebo comparator. Outcomes included faecal bacterial composition (α-diversity, relative abundance), short-chain fatty acids, in adjunct with exercise performance (i.e., time-trial, time to exhaustion, maximal strength). Eighteen studies met the inclusion criteria. Due to methodological heterogeneity, a descriptive synthesis was performed. Changes in faecal microbiota diversity and composition were highly variable and largely minimal. Short-chain fatty acid outcomes were infrequently assessed; only one study reported a significant increase in faecal acetate concentration following yoghurt supplementation containing Bifidobacterium animalis subsp. lactis BL-99. Only seven studies examined the relationship between changes in faecal bacterial profile and performance outcomes, with limited or inconclusive findings. No consistent performance benefits were observed in relation to microbiota changes. Risk of bias and methodological limitations were common, including variation in interventions, outcome measures and microbiota analysis methods. Taken together, the current evidence base remains too limited and heterogeneous to draw firm conclusions about the efficacy of microbiota-targeted interventions for enhancing exercise performance in healthy, active adults. Future studies employing standardised methods, mechanistic outcome measures and longitudinal designs may help clarify the potential of microbiota modulation as a performance-enhancing strategy.

Background/Objectives: The gut microbiome has an important role in immune regulation, and dietary interventions that support a balanced microbiota may help to prevent the development of allergic asthma. Dietary fibers can beneficially affect the intestinal microbiome, but due to the diversity of fiber types, the effects differ. In this study, we investigate the preventive effects of two mixes of short-chain and long-chain (1:1 and 9:1 ratio) fructo-oligosaccharides (FOS) in a mouse model of house dust mite (HDM)-induced allergic asthma. Methods: BALB/c mice received FOS-supplemented (1% w/w) diets before and during intranasal exposures to HDM. Endpoint airway hyperreactivity measurements were performed, followed by the collection of bronchoalveolar lavage fluid (BALF), lung, serum and cecum content. Fecal microbiome composition was determined by DNA sequencing and short-chain fatty acid (SCFA) levels were determined in the cecum, serum and lung. Results: Fecal microbiome analyses revealed an increased abundance of Prevotellaceae after FOS1:1 supplementation in HDM-allergic mice. Additionally, FOS1:1 protected against an HDM-induced increase in basal airway resistance. Both FOS1:1 and FOS9:1 restored the systemic acetate levels in HDM-allergic mice. The two FOS supplementations did not affect HDM-induced inflammatory cell influx in the BALF. However, FOS1:1 increased the frequency of Th1-cells and prevented an HDM-induced increase in the Th2/Th1 balance. Upon ex vivo restimulation with HDM, lung cell suspensions of FOS1:1-fed mice produced less type 2-related cytokines compared to control-supplemented mice, and FOS9:1 followed a similar pattern. Conclusions: Specific short-chain and long-chain FOS ratios differentially affect the microbiome and immune system in a mouse model with HDM-induced allergic airway inflammation. Dietary supplementation with FOS1:1 shifts the immune response away from type 2, suggesting that dietary fibers like FOS1:1 may contribute as a part of a broader strategy to modulate HDM-induced allergic asthma.

Longitudinal and integrated analysis of oral and stool microbiome in allogeneic hematopoietic cell transplantation recipients.

ABSTRACTBackground and Aim:Proteases are key enzymes that hydrolyze peptide bonds enhancing the utilization of feed protein, improving nutrient efficiency, and reducing the need for costly protein ingredients. Despite their growing use in animal nutrition, comparative studies between fungal and microbial proteases in ruminants remain scarce. This study aimed to evaluate the influence of fungal and microbial proteases (25 U/g each) on the microbial composition of rumen fluid and feces, and on the chemical composition of digestive contents in Kazakh White Head bulls.Materials and Methods:Twenty bulls (14–15 months old; 310–320 kg) fitted with rumen fistulas were divided into three groups: a control group and two treatment groups, each receiving a basal diet supplemented with either fungal or microbial protease. Rumen fluid and fecal samples were analyzed for taxonomic profiles using next-generation sequencing (MiSeq, Illumina) of the 16S ribosomal RNA V3–V4 region. Chemical composition (dry matter [DM], crude protein [CP], crude fat [CF], crude fiber, and ash) was determined according to GOST mass fraction of DM 31640, mass fraction of CP 13496.4, mass fraction of CF 13496.15, mass fraction of crude fiber 31675, and mass fraction of crude ash 26226 standards. Statistical analysis was performed using the Mann–Whitney U-test (p ≤ 0.05).Results:Microbial protease supplementation increased the abundance of beneficial phyla Bacillota (70.1%) and Bacteroidota (19.5%) in rumen fluid, with a corresponding rise in DM (+6.3%), CF (+9.4%), and CP (+7.9%) relative to control. In feces, Bacillota (70.7%) and Bacteroidota (15.5%) predominated. No opportunistic pathogens (e.g., Pseudomonas and Sutterella) were detected in the microbial protease group, indicating improved microbial balance and intestinal protection. Fungal protease exerted milder effects, with modest increases in nutrient fractions.Conclusion:Microbial protease was more effective than fungal protease in optimizing rumen microbiota and enhancing nutrient digestibility in bulls. Its use may support environmentally sustainable livestock production by reducing nitrogen excretion and dependence on high-protein feed ingredients. These findings provide a scientific basis for breed-adapted enzymatic feeding strategies in ruminants.

Associations among Maternal Nutrient Intake and Infant Fecal and Human Milk Microbiomes in Exclusively Breastfeeding Samoan Mother-Infant Dyads.

The defense role of luteolin-β-CD-MOF against acetaminophen induced liver toxicity by regulating of bile acids metabolism and gut microbiota.