Galactooligosaccharides and Limosilactobacillus reuteri synergistically alleviate gut inflammation and barrier dysfunction by enriching Bacteroides acidifaciens for pentadecanoic acid biosynthesis

3'-Sialyllactose and B. infantis synergistically alleviate gut inflammation and barrier dysfunction by enriching cross-feeding bacteria for short-chain fatty acid biosynthesis

Ulcerative colitis (UC) poses significant threats to human health and quality of life worldwide, as it is a chronic inflammatory bowel disease. 3'-sialyllactose (3'-SL) is a key functional component of milk oligosaccharides. This study systematically evaluates the prebiotic effects of 3'-SL and its therapeutic potential in combination with Bifidobacterium infantis (B. infantis) for UC. The findings reveal that 3'-SL and B. infantis synergistically mitigate intestinal inflammation and barrier dysfunction by promoting the production of short-chain fatty acids (SCFAs) through cross-feeding mechanisms among gut microbiota. Individually, 3'-SL, B. infantis, and the synbiotic treatment all effectively alleviated UC symptoms, including reduced weight loss, improved disease activity scores, and prevention of colon shortening. Histopathological and immunofluorescence analyses further demonstrated that the synbiotic treatment significantly ameliorated colonic injury, enhanced barrier function, restored goblet cell counts, increased glycoprotein content in crypt goblet cells, and upregulated the expression of tight junction proteins (ZO-1, occludin, and claudin-1). Notably, the synbiotic treatment outperformed the individual components by better restoring gut microbiota balance, elevating SCFA levels, and modulating serum cytokine profiles, thereby reducing inflammation. These findings provide mechanistic insights into the protective effects of the synbiotic and underscore its therapeutic potential for UC and other intestinal inflammatory disorders.

Restoration of gut integrity by Bacteroides acidifaciens in water-deprived conditions

Water scarcity exerts profound physiological impacts, yet its effects on intestinal microbiota-barrier crosstalk remain poorly understood. This study investigates water-deprivation-induced gut dysbiosis and identifies Bacteroides acidifaciens (B.acidifaciens) as a critical mediator of epithelial barrier resilience. Using a murine model of graded water restriction, we observed colon shortening, villus atrophy, goblet cell loss, and barrier disruption correlated with water-deprivation severity. Oral supplementation of B.acidifaciens restored colonic architecture, enhanced mucin secretion, and ameliorated barrier dysfunction in water-deprived mice. Mechanistically, B.acidifaciens maintained barrier homeostasis by directly stimulating mucus production in intestinal epithelial cells and upregulating the expression of tight junction proteins. These findings establish B.acidifaciens as a critical species in mitigating water-deprivation-induced colon injury and advance our understanding of microbiota-directed interventions for dehydration-associated gastrointestinal disorders.

Pentadecyl®, an odd-chain-rich triglyceride mixture derived from Aurantiochytrium oil, attenuates lipopolysaccharide-induced inflammatory cytokine production in BV-2 microglial cells

BACKGROUND AND AIM

Microglia are the primary immune cells of the central nervous system that play pivotal roles in health and disease. Abnormally activated microglia secrete proinflammatory factors and play essential roles in neurodegenerative disease progression. This study investigated the potential effects of Pentadecyl, rich in odd-numbered fatty acids, such as pentadecanoic acid, isolated from Aurantiochytrium limacinum, on the lipopolysaccharide (LPS)-induced immune response of BV-2 microglial cells.

EXPERIMENTAL PROCEDURE

Cell viability was detected using MTT and LIVE/DEAD assays. mRNA and protein levels of inflammatory cytokines and signaling factors were assessed using real-time PCR and western blotting, respectively.

RESULTS AND CONCLUSION

Pentadecyl did not affect MTT-reducing activity or the number of dead cells stained with ethidium homodimer-1. Pentadecyl selectively mitigated the LPS-induced overproduction of pro-inflammatory cytokines, including interleukin (IL)-6 and IL-1β, at the transcriptional and protein levels, whereas tumor necrosis factor-alpha (TNF-α) expression remained unchanged. Western blot analysis showed that Pentadecyl downregulated the LPS-induced increase in the phosphorylation of signal transducer and activator of transcription 3 (STAT3) but did not affect the phosphorylation of p65, a component of nuclear factor-kappa B, or p38 and c-Jun N-terminal kinase, both of which are mitogen-activated protein kinases. Similar to Pentadecyl, Stattic, a representative STAT3 inhibitor, preferentially suppressed the LPS-induced upregulation of IL-6 and IL-1β mRNA expression, whereas its inhibitory effect on TNF-α expression was relatively modest. These results indicate that Pentadecyl suppresses LPS-induced pro-inflammatory cytokine production without affecting cell survival by regulating the STAT3 signaling pathway in BV-2 cells.

In vitro fermentation of Auricularia auricula polysaccharides and their regulation of human gut microbiota and metabolism

Auricularia auricula is abundant in polysaccharides that received increasing attention due to their variety biological activities and prebiotic potential. In order to explore the role of A. auricula polysaccharides (AAP) in regulating human gut microbiota and metabolic health, this study employed metagenomic and metabolomic analyses to examine the impact of AAP on the gut microbiota via in vitro fecal fermentation experiments. After in vitro fermentation, the data indicated that gut microbiota utilized AAP to produce rich short-chain fatty acids (SCFAs) including acetic acid, propionic acid, butyric acid and modulate gut microbiota structure, such as increasing the proportion of Bacteroidetes to Firmicutes, elevating the abundance of beneficial bacteria, including Bacteroides, especially the Parabacteroides, and inhibiting the abundance of harmful bacteria such as Bilophila, Morganella, and Escherichia-Shigella. Furthermore, the metabolomic analysis indicated that AAP utilization by gut microbes substantially alters the metabolic profile, in which 26 potential biological biomarkers were found and affects tryptophan, bile acids, purines, and butyric acid pathways to promote host health. In conclusion, this research indicated that AAP has a prebiotic potential, which can regulate the gut microbiota and promote host health. Moreover, this study provided scientific evidence for using AAP as a functional food with prebiotic effect.

Unraveling the protective mechanisms and bioactive components of litchi polysaccharides in intestinal health

In recent years, the rise in intestinal disease has driven the hunt for safer, cost-effective alternatives to traditional, side-effect-laden medications. Litchi polysaccharide (LP), derived from litchi pulp, has emerged as a potential intestinal protector, but its efficacy has not been well-established. Our study have demonstrated LP significantly preserves the integrity of the intestinal barrier in both Caenorhabditis elegans model and antibiotic-exposed mice. Furthermore, LP regulates the gut microbiota, promoting the dominance of beneficial bacteria such as Anaerostipes and Lachnoclostridium in antibiotic-exposed mice and elevating the levels of short-chain fatty acids (SCFAs). LP2-a, a key component making up 11.13 % of LP and with a molecular weight of 72,477 Da, has been isolated and identified as the main active agent. Its molecular structure, featuring galactose and arabinose and possessing a main chain composed of specific sugar units and side chains, is crucial for its protective effects. In C. elegans, LP2-a regulates the expression of intestinal structure-related genes, including up-regulating the expression of act-5 and down-regulating the levels of ajm-1, erm-1, and zoo-1, protecting the integrity of the intestinal barrier. This study provides a theoretical foundation for the potential use of LP, particularly LP2-a, in the treatment of intestinal diseases.

Pentadecanoic acid attenuates thioacetamide-induced liver fibrosis by modulating oxidative stress, inflammation, and ferroptosis pathways in rat

Pentadecanoic acid (PDA) has been reported as a histone deacetylase 6 inhibitor. Numerous studies have shown that Histone deacetylases (HDACs) are significantly involved in the development of fibrosis. The present study focused on assessing the anti-fibrotic properties of PDA in ameliorating hepatic fibrosis induced by thioacetamide (TAA) in Wistar rats. PDA was administered orally at the doses of 10, 20 and 40 mg/kg daily, whereas TAA was administered intraperitoneally at a dose of 200 mg/kg twice weekly, for a period of 9 weeks. Administration of TAA significantly increased the relative and absolute liver weight, alanine transaminase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamyl transferase (γ-GT), myeloperoxidase (MPO), malondialdehyde (MDA) and reduced the glutathione (GSH) levels and PDA intervention restored the same. PDA treatment ameliorated TAA-induced collagen deposition and infiltration of inflammatory cells as revealed by Sirius red and H&E staining. Additionally, histopathological analysis revealed lymphocyte infiltration, collagen build up, development of bridging fibrosis, degeneration of the portal triad, iron accumulation, and necrosis in TAA-treated rats. The intervention with PDA significantly mitigated these pathological changes. PDA treatment significantly downregulated the expressions of TGF-β1, α-SMA, NLRP3, NF-κB and HDAC6 against TAA-induced liver damage. The present study clearly demonstrated that PDA treatment significantly alleviated TAA-induced hepatic fibrosis by ameliorating the inflammatory markers.

Association between plasma odd-chain fatty acid levels and immune cell traits in psoriasis: insights from a prospective cohort study

Background/Objectives

Psoriasis is a chronic, immune-mediated skin disease frequently linked to metabolic dysregulation. Odd-chain fatty acids (OCFAs), a group of bioactive lipids, have been implicated in inflammation and metabolic health; however, their role in psoriasis remains poorly defined. This study aimed to investigate the associations between plasma OCFA levels, white blood cell (WBC) traits, and psoriasis severity.

Methods

A total of 235 patients with moderate-to-severe plaque psoriasis were enrolled from the Shanghai Psoriasis Effectiveness Evaluation CoHort. Baseline plasma OCFA concentrations were measured using gas chromatography-mass spectrometry, and routine hematologic parameters were extracted from clinical records. Psoriasis severity was assessed using the Psoriasis Area and Severity Index, Body Surface Area, Dermatology Life Quality Index, and the Hospital Anxiety and Depression Scale for Anxiety and Depression. Therapeutic response was evaluated at weeks 12 and 28 based on clinical improvement. Multivariate linear and logistic regression analyses, stratified subgroup analyses, and restricted cubic spline models were employed.

Results

Higher plasma levels of C15:0 were significantly associated with increased total WBC and neutrophil counts. C17:0 levels were positively associated with WBC counts among females and older adults, and inversely associated with eosinophil counts in females and individuals with normal BMI. Additionally, C17:1n7 levels were positively associated with lymphocyte and monocyte counts. Total OCFA levels were also positively associated with overall WBC and neutrophil counts. These associations varied by sex, age, BMI, smoking and alcohol consumption history, and the presence of comorbidities such as psoriatic arthritis, hypertension, and type 2 diabetes. While no significant associations were observed between plasma OCFA levels and psoriasis severity or treatment response in the overall cohort, stratified analyses revealed potential relationships in specific subgroups.

Conclusions

Plasma OCFAs are differentially associated with circulating immune cell profiles in patients with psoriasis, suggesting a potential immunomodulatory role. Although OCFAs were not linked to overall disease severity or short-term treatment outcomes, subgroup-specific associations indicate their relevance in particular clinical phenotypes. These findings highlight the need for further longitudinal studies to clarify the role of OCFAs in immune regulation, disease progression, and comorbidity management in psoriasis.

Aging-Associated Amyloid-β Plaques and Neuroinflammation in Bottlenose Dolphins (Tursiops truncatus) and Novel Cognitive Health-Supporting Roles of Pentadecanoic Acid (C15:0)

There is an urgent need to identify interventions that broadly target aging-related cognitive decline and progression to Alzheimer's disease (AD). Bottlenose dolphins (Tursiops truncatus) have histologic changes similar to AD in humans, and they also develop shared age-associated co-morbidities identified as risk factors for AD in humans, including type 2 diabetes, ferroptosis, and iron overload, which can be driven by nutritional C15:0 deficiency. We hypothesized that (1) dolphins would have amyloid beta (Aβ) plaques and neuroinflammation that paralleled that of humans in relation to age-related progression, quantitative concentration, and brain region; and (2) C15:0 would have dose-dependent activities relevant to protecting cognitive health. Quantitative immunohistochemistry staining was used to assess 68 tissues from archived brains of 19 Navy dolphins to evaluate associations among amyloid beta (Aβ) plaques and neuroinflammation by brain region, sex, and age group. Further, dose-dependent C15:0 activities, using a third-party panel intended to screen for potential AD therapeutics, were evaluated. Similar to humans, dolphins had the highest Aβ plaque density variation in the hippocampus (90th percentile of 4.95 plaques/mm2), where plaque density increased with age (p = 0.05). All measured markers of neuroinflammation were detected, including the highest concentrations of activated microglia (CD68+) in the hippocampus (0.46 ± 0.38 cells/mm2). C15:0 was a dose-dependent inhibitor of two targets, fatty acid amide hydrolase (FAAH) (IC50 2.5 µM, 89% maximum inhibition at 50 µM relative to URB597) and monoamine oxidase B (MAO-B) (IC50 19.4 µM, 70% maximum inhibition at 50 µM relative to R(-)-Deprenyl). These activities have demonstrated efficacy against Aβ formation and neuroinflammation, including protection of cognitive function in the hippocampus. These findings suggest that, in addition to protecting against AD co-morbidities, C15:0 may play a distinct role in supporting cognitive health, especially at higher concentrations.

Baseline abundance of Akkermansia muciniphila and Bacteroides acidifaciens in a healthy state predicts inflammation associated tumorigenesis in the AOM/DSS mouse model

Numerous studies demonstrate that intestinal microbiota contribute to colorectal cancer (CRC), which is often associated with dysbiosis. Most of the data were obtained from studies on CRC patients, making it challenging to determine whether alterations in microbiota are a consequence of the pathology or whether they actively drive its progression. Several studies using laboratory animals suggest that gut microbiota may be involved in both the onset and progression of CRC. In the present study we utilized the azoxymethane-dextran sulfate sodium (AOM/DSS) mouse model of CRC to investigate the contribution of healthy-state microbiota to inflammation-associated tumorigenesis. Two cohorts of C57BL/6 mice harboring different intestinal microbiota demonstrated different susceptibility to AOM/DSS treatment. Sequencing of 16S rRNA bacterial DNA from fecal samples revealed Akkermansia muciniphila and Bacteroides acidifaciens as marker features in the healthy-state microbiota (before AOM/DSS administration), which showed a strong positive correlation with tumor incidence. Moreover, the healthy-state abundance of these markers, considered beneficial bacteria, was strongly positively correlated with the sulfate-reducing bacteria Desulfovibrio fairfieldensis identified as a marker of chronic colitis-associated microbiota. Furthermore, the abundances of these marker features, associated with CRC outcome, correlated with the expression of interferon gamma and nitric oxide synthase 2 genes in colon tissue during the early stage of DSS-induced intestinal inflammation. In contrast to multiple studies demonstrating the anti-inflammatory properties of A. muciniphila and B. acidifaciens, our results point out their potential adverse effect under specific conditions of genotoxicity and inflammation in the intestine. Taken together, our findings suggest a complex, context-dependent role of commensal microbiota in inflammation-associated dysbiosis and CRC.

Yinzhihuang formula modulates the microbe‒gut‒liver axis and bile acid excretion to attenuate cholestatic liver injury

BACKGROUND

Cholestatic liver injury is a hepatobiliary disorder primarily characterized by cholestasis, which significantly contributes to liver damage. The Yinzhihuang (YZH) oral preparation is an effective clinical treatment for cholestatic liver injury; however, the specific mechanism of action has not been clarified.

PURPOSE

This study investigated YZH's pharmacological mechanisms associated with the microbe‒gut‒liver axis in cholestatic mice, offering new perspectives for the treatment of cholestasis.

METHODS

YZH's protective effects were evaluated by evaluating serum liver injury indices and liver staining in an alpha-nephthyl isothiocyanate (ANIT)-induced intrahepatic cholestasis mouse model. Colon hematoxylin‒eosin (H&E) and alcian blue staining and FITC‒dextran leakage assays were performed to assess intestinal barrier integrity. Fluorescence in situ hybridization was employed to analyze bacterial translocation. Additionally, 16S rRNA sequencing, fecal microbiota transplantation, and bile acid metabolomics analysis were conducted to examine the relationships among the microbiome, bile acid metabolism, and YZH formula.

RESULTS

We found that YZH administration alleviated symptoms of ANIT-induced hepatic pathological injury and fibrosis. In addition, YZH reduced the transfer of gut bacteria to liver tissue by maintaining an intact intestinal barrier. Notably, YZH influenced the intestinal microbiota composition, upregulated the abundance of bile acid metabolism-associated probiotic bacteria, including Clostridiales, Lachnospiraceae and Bifidobacterium pseudolongum; and downregulated the abundance of Escherichia-Shigella and Serratia, thereby promoting bile acid excretion.

CONCLUSION

YZH protects against cholestatic liver damage by promoting bile excretion and maintaining intestinal mucosal barrier integrity. Furthermore, YZH alleviates cholestasis in a gut microbiota-dependent manner, and upregulation of probiotics may be crucial for YZH's influence on bile acid metabolism.

Galacto-oligosaccharides alleviate experimental lactose intolerance associated with gut microbiota in mice

Introduction

Galacto-oligosaccharides (GOS) are beneficial for alleviating lactose intolerance (LI). GOS have the ability to modify the composition of the intestinal microbiota. The development of intestinal diseases could be influenced by the composition of the gut microbiota. Nevertheless, it remains unclear whether gut microbiota exerts an effect when GOS alleviate LI, whether alterations in composition of the intestinal microbiota influence inflammatory response and lactose digestion.

Methods

We first investigated the effects of GOS on mice with established lactose intolerance. Next, we demonstrated that prophylactic supplementation with GOS also conferred similar benefits.

Results

The results showed that GOS enhanced anti-inflammatory, antioxidant, and gut barrier function. We observed that GOS mediated a change in the gut microbiome by increasing the abundance of Lactobacillus. GOS pre-supplementation reduced incident LI, enhanced anti-inflammatory, antioxidant, and gut barrier function, and markedly altered the gut microbiome by significantly enriching Bifidobacterium. Collectively, the alleviation of LI by GOS suggests an intimate involvement of probiotics.

Discussion

This study demonstrates that GOS ameliorated LI in a gut microbiota-dependent manner. Our findings provide novel evidence that GOS substitute for lactase and serve as a potential modulator of the gut microbiota for the prevention of LI.

Dietary Qiwenghuangbo powder-enriched Limosilactobacillus reuteri protects the intestinal epithelium and alleviates inflammation via a strain-specific mechanism

BACKGROUND

Qiwenghuangbo powder (QP), composed of Astragalus, Phellodendron chinensis, and Radix pulsatilla, is a traditional Chinese herbal formula, but its effects on weaned piglets remained unclear.

METHODS

Weaned piglets fed with 0.5 kg/t QP (QP1), 1 kg/t QP (QP2), low-zinc oxide (ZnO; negative control), and high-ZnO (positive control) diets in two phases, respectively, and the growth performance, intestinal morphology, cytokines, and microbial communities were profiled. The mouse models of colitis induced by Citrobacter rodentium and dextran sulfate sodium (DSS) were employed to elucidate the potential role of QP-fed enriched key species.

RESULTS

Dietary 1.0 kg/t QP alleviated diarrhea and inflammation and improved intestinal development and growth performance of weaned piglets. Moreover, this dietary intervention notably altered microbiota composition, characterized by the enrichment of Limosilactobacillus reuteri. Furthermore, out of three isolated L. reuteri, two strains could alleviate pathogen infection and intestinal inflammation, respectively. Specifically, the anti-inflammatory effect of one strain was achieved by promoting the colonization resistance of C. rodentium as significantly reduced pathogen loads. The other strain mitigated DSS-induced colitis by enhancing the goblet cell function and inhibiting the secretion of pro-inflammatory cytokines, particularly interleukin-1β (IL-1ß) and tumor necrosis factor-α (TNF-α).

CONCLUSIONS

Dietary QP improved the growth performance and intestinal health of weaned piglets by promoting the colonization of L. reuteri. The isolated commensal L. reuteri control colitis in a strain-specific mechanism, highlighting the potential of QP and L. reuteri in providing evidence for gut health promotion.

Recent insights and advances in gut microbiota's influence on host antiviral immunity

A diverse array of microbial organisms colonizes the human body, collectively known as symbiotic microbial communities. Among the various pathogen infections that hosts encounter, viral infections represent one of the most significant public health challenges worldwide. The gut microbiota is considered an important biological barrier against viral infections and may serve as a promising target for adjuvant antiviral therapy. However, the potential impact of symbiotic microbiota on viral infection remains relatively understudied. In this review, we discuss the specific regulatory mechanisms of gut microbiota in antiviral immunity, highlighting recent advances in how gut microbiota regulate the host immune response, produce immune-related molecules, and enhance the host's defense against viruses. Finally, we also discuss the antiviral potential of oral probiotics.

Lactobacillus fermentum 016 Alleviates Mice Colitis by Modulating Oxidative Stress, Gut Microbiota, and Microbial Metabolism

Ulcerative colitis (UC) is a chronic and progressive inflammatory gastrointestinal disease closely associated with gut microbiota dysbiosis and metabolic homeostasis disruption. Although targeted microbial therapies are an emerging intervention strategy for inflammatory bowel disease (IBD), the mechanisms by which specific probiotics, such as Lactobacillus fermentum 016 (LF), alleviate UC remain unclear. The current study evaluated the effects of LF supplementation on gut health in a basal model using C57BL/6 mice. Subsequently, the preventive effects and mechanisms of LF supplementation on DSS-induced UC were systematically investigated. According to our findings, LF supplementation revealed immunoregulatory capabilities with significantly altered gut the composition of microbiota and metabolic activities, particularly enhancing tryptophan metabolism. In the UC model, LF supplementation effectively mitigated weight loss, increased the disease activity index (DAI), and alleviated diarrhea, rectal bleeding, and colon shortening. Moreover, it reduced colonic pathological damage and histological injury scores. LF intervention improved antioxidant markers and intestinal mucosal barrier function with the activation of the Nrf2-Keap1 signaling pathway and regulation of systemic inflammatory markers, i.e., IL-1β, IL-6, TNF-α, IFN-γ, IL-4, and IL-10. Importantly, LF supplementation reversed metabolic disturbances by significantly increasing the abundance of beneficial genera (e.g., g_Dubosiella, g_Faecalibaculum, g_Odoribacter, g_Candidatus_saccharimonas, g_Roseburia, and g_Eubacterium_xylanophilum_group) and elevating tryptophan metabolites (e.g., melatonin, kynurenic acid, 3-indoleacetic acid, 5-methoxytryptophan, and 5-hydroxyindoleacetic acid). In conclusion, Lactobacillus fermentum 016 exhibits potential for regulating gut microbiota homeostasis, enhancing tryptophan metabolism, and alleviating UC, providing critical insights for developing probiotic-based precision therapeutic strategies for IBD.

Oral microbiota in preschoolers with rampant caries: a matched case-control study

Rampant caries is identified by rapid onset, severe decay affecting multiple surfaces, and early pulp infection. This case-control study was conducted to investigate the disparities in oral microbiota between children affected by rampant caries and their caries-free counterparts. A total of 88 preschool children, with matched distribution of sex and age in both the case and control groups, participated in this study. Children's oral health-related behaviors were reported by parents, salivary pH levels were assessed using a portable pen-type pH meter, and supragingival dental plaque was analyzed by 16S rRNA gene sequencing. Children with rampant caries exhibited lower salivary pH levels, poorer toothbrushing habits, and more frequent consumption of sugary snacks. Veillonella, enriched in caries-free children, showed a positive correlation with salivary pH levels and a negative correlation with candy consumption. Conversely, Fusobacterium and Neisseria, more abundant in children with rampant caries, positively correlated with the frequency of candy consumption. Furthermore, Streptococcus mutans, Porphyromonas gingivalis, and Bacteroides acidifaciens were identified as potential oral microbiome markers for differentiating preschoolers with rampant caries from their caries-free peers. B. acidifaciens, typically found in the gut, has been rarely reported in the field of oral health. More well-designed cohort studies are recommended to elucidate the mechanisms through which gut microbiota influences rampant caries in pediatric patients and offer insights into effective strategies for caries management in young children. KEY POINTS: • Lower salivary pH levels in children with rampant caries. • Biomarkers for predicting rampant caries. • Impact of oral health-related behaviors on oral microbiota.