Gut microbiota and IBD: causation or correlation?

Alterations in mucosa branched N-glycans lead to dysbiosis and downregulation of ILC3: a key driver of intestinal inflammation

The perturbation of the symbiotic relationship between microbes and intestinal immune system contributes to gut inflammation and Inflammatory Bowel Disease (IBD) development. The host mucosa glycans (glycocalyx) creates a major biological interface between gut microorganisms and host immunity that remains ill-defined. Glycans are essential players in IBD immunopathogenesis, even years before disease onset. However, how changes in mucosa glycosylation shape microbiome and how this impact gut immune response and inflammation remains to be clarified. Here, we revealed that alterations in the expression of complex branched N-glycans at gut mucosa surface, modeled in glycoengineered mice, resulted in dysbiosis, with a deficiency in Firmicutes bacteria. Concomitantly, this mucosa N-glycan switch was associated with a downregulation of type 3 innate lymphoid cells (ILC3)-mediated immune response, leading to the transition of ILC3 toward an ILC1 proinflammatory phenotype and increased TNFα production. In addition, we demonstrated that the mucosa glycosylation remodeling through prophylactic supplementation with glycans at steady state was able to restore microbial-derived short-chain fatty acids and microbial sensing (by NOD2 expression) alongside the rescue of the expression of ILC3 module, suppressing intestinal inflammation and controlling disease onset. In a complementary approach, we further showed that IBD patients, often displaying dysbiosis, exhibited a tendency of decreased MGAT5 expression at epithelial cells that was accompanied by reduced ILC3 expression in gut mucosa. Altogether, these results unlock the effects of alterations in mucosa glycome composition in the regulation of the bidirectional crosstalk between microbiota and gut immune response, revealing host branched N-glycans/microbiota/ILC3 axis as an essential pathway in gut homeostasis and in preventing health to intestinal inflammation transition.

Advances in Fecal Microbiota Transplantation for Gut Dysbiosis-Related Diseases

This article provides an overview of the advancements in the application of fecal microbiota transplantation (FMT) in treating diseases related to intestinal dysbiosis. FMT involves the transfer of healthy donor fecal microbiota into the patient's body, aiming to restore the balance of intestinal microbiota and thereby treat a variety of intestinal diseases such as recurrent Clostridioides difficile infection (rCDI), inflammatory bowel disease (IBD), constipation, short bowel syndrome (SBS), and irritable bowel syndrome (IBS). While FMT has shown high efficacy in the treatment of rCDI, further research is needed for its application in other chronic conditions. This article elaborates on the application of FMT in intestinal diseases and the mechanisms of intestinal dysbiosis, as well as discusses key factors influencing the effectiveness of FMT, including donor selection, recipient characteristics, treatment protocols, and methods for assessing microbiota. Additionally, it emphasizes the key to successful FMT. Future research should focus on optimizing the FMT process to ensure long-term safety and explore the potential application of FMT in a broader range of medical conditions.

Baicalin n-butyl ester alleviates inflammatory bowel disease and inhibits pyroptosis through the ROS/ERK/P-ERK/NLRP3 pathway in vivo and in vitro

BACKGROUND

Baicalin is a flavonoid extracted from dried roots of the plant Scutellariabaicalensis. Baicalin n-butyl ester (BNE) is a flavonoid obtained by esterification of baicalin and has anti-inflammatory and antioxidant effects.

PURPOSE

The therapeutic efficacy and potential mechanism of BNE in inflammatory bowel disease remain unclear. This study investigated the effects and underlying mechanisms of BNE in ulcerative colitis.

METHODS

Dextran sulfate sodium (DSS) was used to construct a mouse model of ulcerative colitis, and mice were given intragastric administration of BNE. During the experiment, the changes of body weight and hematochezia of mice were observed. At the end of administration, the levels of inflammatory factors, colonic microbial changes and pyroptosis of colonic cells were measured. Mouse intestinal epithelial cells were stimulated by lipopolysaccharide/adenosine-5'-triphosphate to establish an in vitro model. ELISA, qRT-PCR and immunoblotting were used to explore the effect and mechanism of BNE on pyroptosis.

RESULTS

In vivo, BNE drastically attenuated ulcerative colitis symptoms by relieving body weight loss, a decline in colon length, and destruction of colon tissue structure. BNE also reduced the secretion of pro-inflammatory cytokines, including IL-1β, IL-18, and TNF-α, and reactive oxygen species (ROS). Furthermore, 16S rRNA sequencing analyses of gut microbiota revealed that BNE reversed gut microbiota dysbiosis by reducing the abundance of unclassified-Clostridia-UCG-014 and increasing that of Lachnospiraceae. BNE also inhibited cell pyroptosis in mice with DSS-induced colitis. In vitro analyses showed that BNE decreased the secretion of IL-1β, IL-18, TNF-α, and ROS in lipopolysaccharide/adenosine-5'-triphosphate-stimulated mouse intestinal epithelial cells, and it inhibited pyroptosis mediated by oligomeric domain-like receptor protein 3 (NLRP3). Addition of ROS scavenger and ERK inhibitor further confirmed that BNE down-regulated ROS and inhibited the phosphorylation of ERK, thus inhibiting NLRP3-mediated cell pyroptosis. The magnetic beads pull-down assay showed that BNE had the capacity to bind directly to the ERK proteinin MODE-K cells.

CONCLUSION

BNE protects against colitis by increasing the abundance of Lachnospiraceae in vivo and suppressing pyroptosis via binding ERK protein and inhibiting ROS/ERK/P-ERK/NLRP3 in vivo and in vitro.

Enhancing colonic health with encapsulated grape seed anthocyanins: Oral capsule for Colon-targeted delivery

Grape seed anthocyanins (GSA) offer health benefits and protect against diseases, including colitis. Its unpleasant smell and instability prevent widespread application. Antisolvent pretreatment GSA was encapsulated in chitosan-phytic acid 3D gel network. SEM and X-ray diffraction results demonstrate that pretreatment reduces GSA particle size and exhibits amorphous structure. FTIR confirmed they were physically encapsulated and not covalently bound. Its subsequent simulations digestion and fermentation showed only 26.69 % upper digestive tract leakage and altered gut microbiota and metabolites profile. In DSS-induced colitis model, it ameliorated the symptoms, including diarrhea, bloody stools, weight loss, and DAI score. Additionally, it regulates colitis mice pro- and anti-inflammatory cytokines, modifies cecum and colon SCFA profile, improves intestinal barrier, and restores colonic cell redox equilibrium. Collectively, GSA ameliorates experimental colitis via inhibiting TRL4/NF-κB and activating Nrf2 signaling pathway. In conclusion, we propose our GSA capsule can effectively deliver an intact parent form of GSA to the colon and has the potential to be a colonic health strategy.

Lack of IFN-γ response of human uterine myometrium-derived MSCs significantly improve multiple IBD parameters compared to bone marrow MSCs: Implications for anti-TNFα-refractory patients

The clinical efficacy of mesenchymal stem cell (MSC) therapy for inflammatory bowel disease (IBD) is inconsistent and often fails to match promising preclinical findings. To improve outcome, we compared MSCs isolated from human uterine myometrium (Ut), a readily-available tissue source from a unique immune niche, to bone marrow (BM) MSCs, the most common source, in a murine IBD model with mechanisms underlying differential effects. In this study, human BMMSCs and UtMSCs were intravenously administered to mice with dextran sulfate sodium-induced colitis and evaluated for disease activity, microbiome composition, and cellular immunity. Bioinformatics analyses including patient data were performed to further specify involved mechanisms with subsequent functional validation performed. We found that UtMSC but not BMMSC treatment significantly reversed disease parameters by improving microbiome and reducing mesenteric lymph node IFN-γ and IL-17A-secreting T cells. Transcriptomic analysis revealed UtMSCs had reduced MHC II pathway activation compared to BMMSCs. Functional validation confirmed UtMSCs compared to BMMSCs expressed lower IFN-γ receptors, prevent MHC II-mediated human unstimulated T cell activation, and modulated stimulated T helper (Th) cells away from effector phenotypes while increasing regulatory T cells (Tregs) and IL-10 levels. Bioinformatics from IBD patients resistant to non-T cell-specific therapies implicated persistent MHC II-mediated Th1/Th17 activation as key drivers of disease. Overall, UtMSCs outperformed BMMSCs in improving microbiota, avoiding IFN-γ responses, and modulating overall Th responses, suggesting this MSC source may offer more significant effectiveness for IBD and Th1/Th17-mediated conditions. Our findings also highlight that understanding MSC source-specific therapeutic mechanisms is crucial for optimizing clinical therapies.

CGA protects against experimental colitis by modulating host purine metabolism through the gut microbiota

OBJECTIVE

Alterations in the gut microbiota may contribute to the development of inflammatory bowel disease (IBD). Chlorogenic acid (CGA), a product of the esterification of caffeic acid and quinic acid, is one of the most abundant polyphenols in the human diet and has potential beneficial effects on gut function. However, the underlying mechanisms remain unclear. In this study, the pharmacological effects of CGA on colitis and the potential underlying mechanisms were investigated.

METHODS

A mouse model of colitis was induced via the use of 4 % dextran sulfate sodium (DSS), and the mice were treated with 200 mg/kg CGA. Body weight, colon length, colon tissue pathology, and plasma and colon inflammatory cytokine levels were assessed. RNA sequencing was used to detect changes in gene expression in mouse colon tissues, and 16S rRNA sequencing was used to analyze the composition and structure of the gut microbiota. Fecal metabolomic analysis was performed, and fecal microbiota transplantation (FMT) was used to evaluate the contribution of the gut microbiota.

RESULTS

CGA significantly alleviated DSS-induced colitis, alleviating intestinal mucosal barrier damage and gut microbiota dysbiosis. It significantly enriched bacteria that produce short-chain fatty acids (SCFAs). CGA inhibited the accumulation of purine metabolites derived from the microbiota and suppressed immune-related signaling cascades, exerting immunomodulatory effects. Furthermore, the gut microbiota of CGA-treated mice alleviated DSS-induced colitis through FMT.

CONCLUSION

CGA alleviates colitis in a gut microbiota-dependent manner, potentially providing a new strategy for the treatment of IBD.

Toxicological effects of micro/nanoplastics and benzo[a]pyrene on cellular and molecular responses of Apostichopus japonicus (Selenka, 1867) during intestinal regeneration

Micro(nano)plastics (M/NPs) are pervasive in marine environments. Benzo[a]pyrene (B[a]P), a typical polycyclic aromatic hydrocarbon (PAH), possesses teratogenic, mutagenic, and carcinogenic properties. B[a]P can accumulate on M/NPs, altering their toxicity. This study investigated individual and combined effects of M/NPs and B[a]P on the intestinal regeneration of the benthic invertebrate Apostichopus japonicus. Eviscerated sea cucumbers were exposed to 0.1 mg L-1 M/NPs (80 nm [NP80] or 20 μm [MP20]) and/or 0.03 μg L-1 B[a]P for 28 days. Cell proliferation, antioxidant and immunoenzyme activity, gene expression, and microbial community in the regenerated intestine were assessed. It demonstrated that combined exposure prolonged regeneration process, leading to increased oxidative stress and intestinal damage. Differential gene expression analysis revealed that co-exposure and single NP80 exposure both significantly changed translation-related processes, while single MP20 exposure primarily affected lipid metabolism. All treatments significantly altered the intestinal microbiota. Under the MP20+B[a]P treatment, Ralstonia abundance significantly increased, while Cobetia and Paracoccus abundances decreased. In general, co-exposure exerted more detrimental effects on intestinal regeneration than any single exposure, with MP20+B[a]P demonstrating more severe impacts. This study provides novel insights into the biotoxicity of M/NPs and B[a]P, contributing to better understanding of the detriments of microplastics and PAHs on marine benthic invertebrates.

PPARγ/β/δ Agonists Can Ameliorate Dextran Sodium Sulfate-Induced Colitis and Modulate Gut Microbiota

BACKGROUND AND AIM

Peroxisome proliferator-activated receptors (PPARs), as nuclear receptors, modulate both lipid metabolism and inflammatory/immune processes. This study examines the impact of modulating the activities of the PPAR subtypes PPARβ/ð and PPARγ on the gut microbiota in inflammatory bowel disease (IBD).

METHODS

Mice with dextran sulfate sodium (DSS)-induced acute colitis were treated with the PPARγ agonist pioglitazone, PPARβ/δ agonist GW0742, or their respective antagonists (GW9662, GSK3787). Weight loss, diarrhea severity, hematochezia, and disease activity index were assessed daily. Upon study completion, colon length, histopathology, and mRNA levels of the intestinal barrier and inflammatory markers were measured. Occludin and E-cadherin levels were assessed via immunofluorescence analysis, and cecal samples underwent 16S rRNA sequencing for gut microbiota analysis.

RESULTS

Our findings revealed that the agonists pioglitazone and GW0742 effectively suppressed DSS-induced colitis, improved clinical symptoms, reversed colon shortening, and mitigated histological damage. Conversely, their antagonists, GW9662 and GSK3787, failed to alleviate inflammation and sometimes exacerbated disease indicators. Both agonists modulated DSS-induced dysbiosis by reducing the abundance of proinflammatory cytokine-associated microbiota, including Bacteroides, Enterococcus, and Escherichia-Shigella, while enhancing both α-diversity and β-diversity of the gut microbiome, to restore equilibrium.

CONCLUSION

Our findings reveal that activation of PPARγ and PPARβ/δ can balance the gut microbiota in mice and ameliorate experimental colitis in mice. Thus, PPARγ and PPARβ/δ have protective effects against IBD and could serve as novel therapeutic targets for its treatment.

Gut commensal Alistipes shahii improves experimental colitis in mice with reduced intestinal epithelial damage and cytokine secretion

The commensal bacterium Alistipes shahii is a core microbe of the human gut microbiome and its abundance is negatively correlated with inflammatory bowel diseases (IBDs). However, its fundamental role in regulating inflammatory response remains unknown. Using a dextran sulfate sodium (DSS)-induced colitis mouse model, we examined the effect of A. shahii strain As360 intervention on host inflammatory response and found that A. shahii As360 alleviated disease activity index, colon shortening, and colonic histopathological lesion. The levels of tight junction proteins (mainly ZO1 and claudin-1) were decreased in DSS-induced colitis mice, whereas the levels of these proteins were elevated in colitis mice with A. shahii As360 treatment. In addition, A. shahii As360 treatment led to alterations in cytokine release, especially an increase of IL10. It also led to reduced expressions of mtor and Nlrp3 and increased expression of mTOR inhibitor Ddit4 at the transcriptional level. 16S rRNA amplicon sequencing found that Bacteroides, a producer of short-chain fatty acids (SCFAs), was enriched in the fecal samples of mice with A. shahii treatment. Metabolic analyses found that, following A. shahii As360 treatment, the SCFAs in the fecal content was increased whereas lactic acid was decreased in the cecal content. These findings suggest that supplementation with A. shahii As360 is a promising strategy to prevent colitis.IMPORTANCEAs one of the core microbes and keystone species in the human gut, Alistipes shahii has the potential to inhibit inflammation and improve inflammatory bowel diseases (IBDs) conditions. In this study, we experimentally demonstrated that oral administration of A. shahii As360 alleviated symptoms of colitis, altered the release of cellular inflammatory factors, reduced the intestinal epithelial barrier damage, and changed gut microbiota and fecal metabolites. These findings provide a deeper understanding of the beneficial effects of A. shahii and its perspective for better strategies to prevent IBD.

Research Status and Trends of Gut Microbiota and Intestinal Diseases Based on Bibliometrics

Gut microbiota plays an important role in gut health, and its dysbiosis is closely related to the pathogenesis of various intestinal diseases. The field of gut microbiota and intestinal diseases has not yet been systematically quantified through bibliometric methods. This study conducted bibliometric analysis to delineate the evolution of research on gut microbiota and intestinal diseases. Data were sourced from the Web of Science Core Collection database from 2009 to 2023 and were scientometrically analyzed using CiteSpace. We have found that the number of annual publications has been steadily increasing and showing an upward trend. China and the Chinese Academy of Sciences are the country and institution with the most contributions, respectively. Frontiers in Microbiology and Nutrients are the journals with the most publications, while Plos One and Nature are the journals with the most citations. The field has shifted from focusing on traditional descriptive analysis of gut microbiota composition to exploring the causal relationship between gut microbiota and intestinal diseases. The research hotspots and trends mainly include the correlation between specific intestinal diseases and gut microbiota diversity, the mechanism of gut microbiota involvement in intestinal diseases, the exploration of important gut microbiota related to intestinal diseases, and the relationship between gut microbiota and human gut health. This study provides a comprehensive knowledge map of gut microbiota and intestinal diseases, highlights key research areas, and outlines potential future directions.

An arabinogalactan from Lycium barbarum mitigated DSS caused intestinal injury via inhibiting mucosal damage and regulating the gut microbiota disorder

Intestinal injury and microbiota disorder take part in the development of UC. In this research, we obtained an arabinogalactan (LBP-m) from Lycium barbarum and firstly characterized its physicochemical properties. LBP-m was a homogeneous polysaccharide (172 kDa) consisted of Ara, Gal, Glc, GalA, and GlcA with a mole ratio of 1.00: 0.73: 0.18: 0.20: 0.07, and constructed a →6)-β-Galp(1→ backbone with different Araf branches at O-3 position, which exerted as random coil in PBS with single helical structure. Furthermore, oral administration of LBP-m ameliorated the DSS induced UC from different aspects, including regulating barrier dysfunction by promoting the expression of TJs, elevating the anti-oxidative stress capacity through activating the Nrf2/HO-1 pathway, relieving the mucosal inflammation via inhibiting NF-κB pathway. In addition, LBP-m regulated the gut microbiota disorder by reshaping the microbial composition and enhancing the generation of SCFAs. Our research revealed the physicochemical properties of LBP-m and systematically indicated its mitigative effect against DSS induced UC, which could benefit its application in food and pharmacy fields.

Effects of Perfluorooctane Sulfonic Acid Exposure on Intestinal Microbial Community, Lipid Metabolism, and Liver Lesions in Mice

Perfluorooctane sulfonic acid (PFOS) is a persistent organic pollutant that has attracted much attention due to its wide environmental distribution and potential toxicity. Intestinal microbiota is an important regulator of host health, and its composition and metabolic function are easily interfered with by environmental pollutants. In this study, the effects of PFOS exposure on gut microbiota, lipid metabolism, and host health were investigated in mice. The results showed that PFOS exposure did not significantly change α diversity, but significantly affected the β diversity and community structure of intestinal microflora in mice. At the taxonomic level, the ratio of Firmicutes to Bacteroidetes decreased, and the changes in the abundance of specific bacteria were closely related to liver diseases and lipid metabolism disorders. PFOS exposure also interfered with the gut-liver axis mechanism, increased blood lipids and liver function related indicators in mice, and induced intestinal and liver histological lesions. This study revealed the toxic mechanism of PFOS mediated by intestinal microbiota, providing a new research perspective for health problems caused by environmental pollutants and theoretical support for the formulation of relevant public health policies.

Human-derived microRNA 21 regulates indole and L-tryptophan biosynthesis transcripts in the gut commensal Bacteroides thetaiotaomicron

In the gut, microRNAs (miRNAs) produced by intestinal epithelial cells are secreted into the lumen and can shape the composition and function of the gut microbiome. Crosstalk between gut microbes and the host plays a key role in irritable bowel syndrome (IBS) and inflammatory bowel diseases, yet little is known about how the miRNA-gut microbiome axis contributes to the pathogenesis of these conditions. Here, we investigate the ability of miR-21, a miRNA that we found decreased in fecal samples from IBS patients, to associate with and regulate gut microbiome function. When incubated with the human fecal microbiota, miR-21 revealed a rapid internalization or binding to microbial cells, which varied in extent across different donor samples. Fluorescence-activated cell sorting and sequencing of microbial cells incubated with fluorescently labeled miR-21 identified organisms belonging to the genera Bacteroides, Limosilactobacillus, Ruminococcus, or Coprococcus, which predominantly interacted with miR-21. Surprisingly, these and other genera also interacted with a miRNA scramble control, suggesting that physical interaction and/or uptake of these miRNAs by gut microbiota is not sequence-dependent. Nevertheless, transcriptomic analysis of the gut commensal Bacteroides thetaiotaomicron revealed a miRNA sequence-specific effect on bacterial transcript levels. Supplementation of miR-21, but not of small RNA controls, resulted in significantly altered levels of many cellular transcripts and increased transcription of a biosynthetic operon for indole and L-tryptophan, metabolites known to regulate host inflammation and colonic motility. Our study identifies a novel putative miR-21-dependent pathway of regulation of intestinal function through the gut microbiome with implications for gastrointestinal conditions.

IMPORTANCE

The mammalian gut represents one of the largest and most dynamic host-microbe interfaces. Host-derived microRNAs (miRNAs), released from the gut epithelium into the lumen, have emerged as important contributors to host-microbe crosstalk. Levels of several miRNAs are altered in the stool of patients with irritable bowel syndrome or inflammatory bowel disease. Understanding how miRNAs interact with and shape gut microbiota function is crucial as it may enable the development of new targeted treatments for intestinal diseases. This study provides evidence that the miRNA miR-21 can rapidly associate with diverse microbial cells form the gut and increase levels of transcripts involved in tryptophan synthesis in a ubiquitous gut microbe. Tryptophan catabolites regulate key functions, such as gut immune response or permeability. Therefore, this mechanism represents an unexpected host-microbe interaction and suggests that host-derived miR-21 may help regulate gut function via the gut microbiota.

The effect of a water-soluble β-glucan on intestinal immunity and microbiota in LPS-challenged piglets

The intestine is the largest immune and barrier organ in the body, and diarrhea and even death during piglet development are related to dysfunction caused by intestinal barrier damage and inflammation. A water-soluble β-glucan produced by Agrobacterium ZX09 has been shown to have a beneficial effect on gastrointestinal health. The main objective of this study was to investigate whether pre-feeding β-glucan has a protective effect on LPS-induced immune stress in piglets. In this study, 24 weaned piglets (21-day-old; 6.64 ± 0.16 kg) were assigned to 4 treatments in a two × two factorial design with diet (with or without β-glucan) and immunological challenge (saline or LPS). Piglets were challenged with saline or LPS after 39 days of feeding 0 or 200 mg/kg β-glucan. The results demonstrated that β-glucan supplementation increased the average daily weight gain and daily feed intake, and decreased diarrhea rate of piglets. Intestinal inflammation symptoms and histological changes in LPS-challenged piglets were alleviated by pre-feeding of β-glucan. β-glucan supplementation reduced serum IL-1β (interleukin-1β) and NO (nitric oxide) secretion in piglets after LPS challenge (0.01 < p < 0.05). Supplementation with β-glucan downregulated the mRNA expression of IL-6 in piglets after LPS challenge (0.01 < p < 0.05). β-glucan supplementation enriched the short-chain fatty acid-producing bacteria, such as Agathobacter and Subdoligranulum (0.01 < p < 0.05), and increased the concentrations of propionate and butyrate (0.01 < p < 0.05). In conclusion, pre-feeding β-glucan can enhance piglet immunity and promote piglet growth by influencing gut microbiota composition and metabolism, and alleviate intestinal damage after LPS challenge.

Advancements in the investigation of gut microbiota-based strategies for stroke prevention and treatment

Stroke represents a predominant cause of mortality and disability on a global scale, impacting millions annually and exerting a considerable strain on healthcare systems. The incidence of stroke exhibits regional variability, with ischemic stroke accounting for the majority of occurrences. Post-stroke complications, such as cognitive impairment, motor dysfunction, and recurrent stroke, profoundly affect patients' quality of life. Recent advancements have elucidated the microbiota-gut-brain axis (MGBA), underscoring the complex interplay between gut health and brain function. Dysbiosis, characterized by an imbalance in gut microbiota, is significantly linked to an elevated risk of stroke and unfavorable outcomes. The MGBA plays a crucial role in modulating immune function, neurotransmitter levels, and metabolic byproducts, which may intensify neuroinflammation and impair cerebral health. This review elucidates the role of MGBA in stroke pathophysiology and explores potential gut-targeted therapeutic strategies to reduce stroke risk and promote recovery, including probiotics, prebiotics, pharmacological interventions, and dietary modifications. However, the current prevention and treatment strategies based on intestinal flora still face many problems, such as the large difference of individual intestinal flora, the stability of efficacy, and the long-term safety need to be considered. Further research needs to be strengthened to promote its better application in clinical practice.

Biological functions and therapeutic applications of human mucosal-associated invariant T cells

Mucosal-associated invariant T (MAIT) cells are a unique subset of innate-like T lymphocytes that bridge innate and adaptive immunity. Characterized by their semi-invariant T cell receptor (TCR) and abundant localization in mucosal tissues, MAIT cells recognize microbial metabolites, primarily derived from the riboflavin biosynthesis pathway, presented by the major histocompatibility complex (MHC)-related protein 1 (MR1). This interaction, along with co-stimulatory signals, triggers rapid immune responses, including cytokine secretion and cytotoxic activity, highlighting their importance in maintaining immune homeostasis and combating infections. This review provides an in-depth overview of MAIT cell biology, including development, activation pathways, and functional diversity, highlighting their protective roles in immunity, contributions to diseases like cancer and inflammatory bowel disease (IBD), and context-dependent dual functions in health and pathology. This review also highlights the emerging therapeutic potential of MAIT cells in immunotherapy. Their unique TCR specificity, abundance, and tissue-homing properties make them ideal candidates for engineering novel therapies, such as chimeric antigen receptor (CAR)-MAIT cells, targeting infections, cancers, and autoimmune diseases. Challenges like antigen escape, T cell exhaustion, and CAR design optimization must be addressed to enhance clinical efficacy. In summary, MAIT cells are integral to immune function, and their therapeutic potential presents exciting opportunities for the treatment of a wide range of diseases. Further research is essential to unlock the full potential of these versatile immune cells.

Exploring the CDCA-Scd1 Axis: Molecular Mechanisms Linking the Colitis Microbiome to Neurological Deficits

Inflammatory bowel disease is a risk factor for brain dysfunction; however, the underlying mechanisms remain largely unknown. In this study, we aimed to explore the potential molecular mechanisms through which intestinal inflammation affects brain function and to verify these mechanisms. Mice were treated with multiple cycles of 1% w/v dextran sulfate sodium (DSS) in drinking water to establish a chronic colitis model. Behavioral tests were conducted using the open field test (OFT), tail suspension test (TST), forced swimming test (FST), and Morris water maze test (MWM). Brain metabolomics, transcriptomics, and proteomics analyses were performed, and key target proteins were verified using qPCR and immunofluorescence. Four cycles of DSS administration induced colitis, anxiety, depression, and spatial memory impairment. The integrated multi-omics characterization of colitis revealed decreased brain chenodeoxycholic acid (CDCA) levels as well as reduced stearoyl-CoA desaturase (Scd1) gene and protein expression. Transplantation of the colitis microbiome resulted in anxiety, depression, impaired spatial memory, reduced CDCA content, decreased Scd1 gene and protein expression, and lower concentrations of monounsaturated fatty acids (MUFAs), palmitoleate (C16:1), and oleate (C18:1) in the brain. In addition, CDCA supplementation improved DSS-induced colitis, alleviated depression and spatial memory impairment, and increased Scd1 gene and protein expression as well as MUFA levels in the brain. The gut microbiome induced by colitis contributes to neurological dysfunction, possibly through the CDCA-Scd1 signaling axis. CDCA supplementation alleviates colitis and depressive behavior, likely by increasing Scd1 expression in the brain.

Engineered bacteria and bacterial derivatives as advanced therapeutics for inflammatory bowel disease

Inflammatory bowel disease (IBD), a chronic and relapsing-remitting condition, is inadequately managed by conventional therapies that often lack targeting specificity and carry significant side effects, particularly failing to address intestinal barrier repair and microbial balance. Probiotics, with their strong colonization capabilities, present a novel approach to drug delivery. Various engineering strategies have been developed to enhance the targeting ability of probiotics to inflammation sites, enabling precise delivery or in situ synthesis of therapeutic molecules to expand their multifunctional potential. This review discusses the recent advancements in bacterial modifications, including surface physico-chemical and biological coating, genetic engineering, outer membrane vesicles, minicells, and bacterial ghosts, all of which can enhance therapeutic localization. We also outline critical preclinical considerations, such as delivery frequency, systemic distribution, immune evasion, and gene contamination risks, for clinical translation. These engineered bacteria and bacterial derivatives hold great promise for personalized and sustained IBD treatments, providing a new frontier for therapy tailored to the complex inflammatory environment of IBD.

Effects of high stocking density on the growth performance, intestinal health and bile salts composition of broiler chickens

Introduction

The intestinal dysfunction plays an important role in the decreased growth performance of broiler chickens under high stocking density. Gut microbiota plays an important role in maintaining intestinal health. However, the modulation pathway of gut microbiota by regulating the intestinal barrier and histomorphology remains unknown.

Methods

One hundred and forty-four male Arbor Acres broilers (22-d-old) with similar weight were randomly assigned to two treatments: a high (HSD, 20 broilers/m2) or low stocking density treatment (LSD, 14 broilers/m2), with six replicates per treatment. The experimental period was 20 days, from 22 to 42 days of age.

Results

The final body weight at 42 days of age was lower in the HSD group (P = 0.0013) and average daily feed intake (P = 0.016) and weight gain of broilers from 22 to 42 days decreased (P = 0.012). In the HSD group on day 42, villus height and the ratio of villus height to the crypt depth in the ileum decreased (P < 0.05); mRNA expression of tight junction proteins, occludin (P < 0.01) and ZO1 (P < 0.05), were downregulated; whereas IL-6, TNFα, and NFκB p65 (P < 0.05) and IL-1β (P < 0.01) were upregulated. The HSD treatment increased the relative abundance of Lactobacillus (P = 0.045) and decreased that of Alistipes (P = 0.031). Cecal concentrations of acetic (P < 0.05) and butyric acids (P < 0.05) decreased. Gut metabolites co-metabolized by the host and gut microbiota were altered in the HSD group, with decreases in glycerophospholipid and tryptophan metabolites negatively correlated with Lactobacillus (P < 0.05). The metabolite content of conjugated bile acids decreased and free bile acids increased (P < 0.05) with HSD. Bile salt hydrolase (BSH) was increased in the intestine of HSD-treated broilers (P < 0.01). The total cholic acid content of the HSD group was lower in the jejunum and ileum (P < 0.05) but higher in the cecum than in the LSD group (P < 0.01).

Conclusion

HSD caused dysbiosis of the intestinal microbiota such as increased Lactobacillus, along with enhanced BSH activity and excessive unabsorbed free bile acids. This resulted in ileal epithelial cells damage, inflammation, decreased growth performance of broilers under high stocking densities.

Heart Failure and Gut Microbiota: What Is Cause and Effect?

Emerging evidence highlights the central role of gut microbiota in maintaining physiological homeostasis within the host. Disruptions in gut microbiota can destabilize systemic metabolism and inflammation, driving the onset and progression of cardiometabolic diseases. In heart failure (HF), intestinal dysfunction may induce the release of endotoxins and metabolites, leading to dysbiosis and exacerbating HF through the gut-heart axis. Understanding the relationship between gut microbiota and HF offers critical insights into disease mechanisms and therapeutic opportunities. Current research highlights promising potential to improve patient outcomes by restoring microbiota balance. In this review, we summarize the current studies in understanding the gut microbiota-HF connection and discuss avenues for future investigation.

Metagenome-informed metaproteomics of the human gut microbiome, host, and dietary exposome uncovers signatures of health and inflammatory bowel disease

Host-microbiome-dietary interactions play crucial roles in regulating human health, yet their direct functional assessment remains challenging. We adopted metagenome-informed metaproteomics (MIM), in mice and humans, to non-invasively explore species-level microbiome-host interactions during commensal and pathogen colonization, nutritional modification, and antibiotic-induced perturbation. Simultaneously, fecal MIM accurately characterized the nutritional exposure landscape in multiple clinical and dietary contexts. Implementation of MIM in murine auto-inflammation and in human inflammatory bowel disease (IBD) characterized a "compositional dysbiosis" and a concomitant species-specific "functional dysbiosis" driven by suppressed commensal responses to inflammatory host signals. Microbiome transfers unraveled early-onset kinetics of these host-commensal cross-responsive patterns, while predictive analyses identified candidate fecal host-microbiome IBD biomarker protein pairs outperforming S100A8/S100A9 (calprotectin). Importantly, a simultaneous fecal nutritional MIM assessment enabled the determination of IBD-related consumption patterns, dietary treatment compliance, and small intestinal digestive aberrations. Collectively, a parallelized dietary-bacterial-host MIM assessment functionally uncovers trans-kingdom interactomes shaping gastrointestinal ecology while offering personalized diagnostic and therapeutic insights into microbiome-associated disease.

Sakuranetin ameliorates experimental colitis in a gut microbiota-dependent manner

BACKGROUND

The progression of inflammatory bowel disease (IBD) is closely connected with intestinal flora dysbiosis. Sakuranetin (SAK) is a natural compound with anti-inflammatory and antibiosis activities. We investigated the properties and mechanisms of SAK on IBD-like colitis.

METHODS

Mice with dextran sulfate sodium (DSS)-induced colitis were accomplished to assess the effects of SAK on colitis, as well as intestinal mucosal immune imbalance and intestinal barrier dysfunction. 16S rDNA was used to characterize the intestinal flora, and the short-chain fatty acid (SCFA) content in faeces was calculated using GS‒MS. Faecal microbiota transplantation (FMT) and a pseudosterile model (antibiotic cocktail, ABX) were used to evaluate whether the effects of SAK on colitis were dependent on the gut flora. Pathohistological and biochemical tests were used to estimate the safety of SAK.

RESULTS

SAK significantly ameliorated DSS-induced colitis in mice, verified by decreased weight loss, less colon shortening, and lower disease activity, histology and colonoscopy scores. Moreover, SAK alleviated gut dysbiosis and elevated the abundance of SCFA-producing bacteria in DSS-treated mice. Meanwhile, SAK increased faecal SCFA levels and activated GPR41/43 signalling. SAK also improved Treg/Th17 homeostasis and intestinal barrier function. In addition, ABX and FMT experiments confirmed that the ability of SAK to alleviate colitis was mediated through the gut flora. Finally, a safety experiment revealed that SAK had no significant adverse effects on major organ or liver/kidney function.

CONCLUSIONS

SAK may improve the intestinal immune balance and barrier function by regulating intestinal flora dysbiosis and increasing SCFA production, thereby protecting against colitis.

Effect of fecal microbiota transplantation on ulcerative colitis model in rats: The gut-brain axis

Study objectives

The impact of fecal microbiota transplantation (FMT) on the TLR4/MYD88/NF-kB signaling pathway in the colon in the ulcerative colitis model, as well as the incidence of anxiety behaviors caused by the colitis model was investigated.

Methods

Twenthy four ats were induced with ulcerative colitis using a 4 % acetic acid solution administered intrarectally and were subsequently treated with prednisolone and FMT. The study examined several indicators, such as TLR4, MYD88, and NF-κB mRNA expression, along with oxidative stress factors. Additionally, it examined the relationship between anxiety-related behaviors and colitis and assessed the pro-inflammatory cytokines in the hippocampus.

Results

FMT led to lower disease score index and improved colon tissue pathology findings. This was associated with reduced mRNA expression of TLR4, MYD88, and NF-κB, as well as lower levels of TOS, and higher levels of TAC, GSH, and GSSG in colon tissues. FMT was found to reduce anxiety in both the open field and elevated plus maze tests. Additionally, levels of IL-6 and TNF-a were decreased in the hippocampus.

Conclusions

FMT suppressed acetic acid-induced colitis by inhibiting the TLR4/MYD88/NF-kB signaling pathway. FMT reduced anxiety in open field and plus maze tests, and resulted in decreased levels of IL-6 and TNF-a in the hippocampus.

Gut microbiota in Crohn's disease pathogenesis

Inflammatory bowel diseases (IBDs) are classified into two distinct types based on the area and severity of inflammation: Crohn's disease (CD) and ulcerative colitis. In CD, gut bacteria can infiltrate mesenteric fat, causing expansion known as creeping fat, which may limit bacterial spread and inflammation but can promote fibrosis. The gut bacteria composition varies depending on whether the colon or ileum is affected. Fecal microbiota transplantation (FMT) transfers feces from a healthy donor to restore gut microbiota balance, often used in IBD patients to reduce inflammation and promote mucosal repair. The use of FMT for CD remains uncertain, with insufficient evidence to fully endorse it as a definitive treatment. While some studies suggest it may improve symptoms, questions about the duration of these improvements and the need for repeated treatments persist. There is a pressing need for methods that provide long-term benefits, as highlighted by Wu et al's research.

Research progress on edible mushroom polysaccharides as a novel therapeutic strategy for inflammatory bowel disease

Inflammatory bowel disease (IBD) is a complex condition linked to the gut microbiota, host metabolism, and the immune system. Edible mushroom polysaccharides (EMPs) are gaining attention for their benefits, particularly as prebiotics that help balance gut microbial, a key factor in IBD. With their scalable production, diverse hydrophilic properties, and demonstrated anti-inflammatory effects in both laboratory and animal studies, EMPs show promise for easing IBD symptoms. By supporting a healthy gut microbiome through various mechanisms, EMPs can play an important role in preventing and managing IBD, ultimately benefiting overall health and opening new treatment avenues. This review examines how EMPs affect IBD, focusing on their role in shaping gut microbiota, restoring gut barriers, regulating immune function, and influencing pathways related to colitis. It also explores their impact on the microbiota-gut-multi organ axis and overall host health, as well as the relationship between EMPs preparation, structure, and bioactivity, along with their potential applications in food and medicine. This investigation provides valuable insights into the intricate connections between the gut, immune system, and systemic inflammation system, highlighting how EMPs are key players in this complex interaction.

Odoribacter splanchnicus-derived extracellular vesicles alleviate inflammatory bowel disease by modulating gastrointestinal inflammation and intestinal barrier function via the NLRP3 inflammasome suppression

BACKGROUND

Extracellular vesicles (EVs) derived from specific bacteria exert therapeutic potential on inflammatory diseases. Previous reports suggest the protective role of Odoribacter splanchnicus (O.splanchnicus) in inflammatory bowel disease (IBD). The effect of EVs derived from O.splanchnicus (Os-EVs) and the underlying mechanism on IBD were surveyed here.

METHODS

Os-EVs were derived with ultracentrifugation before characterization by transmission electron microscopy and nanoparticle tracking analysis. Based on IBD model mice induced by dextran sulfate sodium (DSS), the effects of Os-EVs on IBD symptoms, intestinal barrier dysfunction, and colonic apoptosis, inflammation as well as NLRP3 inflammasome activation were analyzed. NLRP3 knockout mice were exploited to judge the role of NLRP3 in Os-EVs against IBD.

RESULTS

Os-EVs were typically shaped as a double concave disc (average diameter = 95 nm). The administration of Os-EVs attenuated DSS-induced body weight loss, colon shortening, disease activity index score, and histological injury in mice. Os-EVs could also relieve intestinal barrier dysfunction and colonic apoptosis, as evidenced by the up-regulation of zona occludens-1 and Occludin and the decrease of TUNEL-positive staining in colonic tissues of IBD mice. Os-EVs downregulated the expression of the interleukin-1β (IL-1β), tumor necrosis factor-α, and IL-6, and elevated IL-10, accompanied by blockage of the NLRP3 inflammasome activation in DSS-induced mice. Furthermore, NLRP3 knockout mice experiments revealed that the protective role of Os-EVs in IBD relies on regulating NLRP3.

CONCLUSION

Our finding indicated that Os-EVs effectively ameliorated IBD through repressing NLRP3, strongly supporting the potential of probiotic-derived EVs for alleviating IBD.

Microbiota translocation following intestinal barrier disruption promotes Mincle-mediated training of myeloid progenitors in the bone marrow

Impairment of the intestinal barrier allows the systemic translocation of commensal bacteria, inducing a proinflammatory state in the host. Here, we investigated innate immune responses following increased gut permeability upon administration of dextran sulfate sodium (DSS) in mice. We found that Enterococcus faecalis translocated to the bone marrow following DSS treatment and induced trained immunity (TI) hallmarks in bone-marrow-derived mouse macrophages and human monocytes. DSS treatment or heat-killed E. faecalis reprogrammed bone marrow progenitors (BMPs), resulting in enhanced inflammatory responses in vitro and in vivo and protection against subsequent pathogen infections. The C-type lectin receptor Mincle (Clec4e) was essential for E. faecalis-induced TI in BMPs. Clec4e-/- mice showed impaired TI upon E. faecalis administration and reduced pathology following DSS treatment. Thus, Mincle sensing of E. faecalis induces TI that may have long-term effects on pathologies associated with increased gut permeability.

Gut microbiota dysfunction in Crohn's disease

Introduction

Crohn's disease (CD) results from alterations in the gut microbiota and the immune system. However, the exact metabolic dysfunctions of the gut microbiota during CD are still unclear. Here, we investigated metagenomic functions using PICRUSt2 during the course of CD to better understand microbiota-related disease mechanisms and provide new insights for novel therapeutic strategies.

Methods

We performed 16S rRNA-based microbial profiling of 567 faecal samples collected from a cohort of 383 CD patients, including 291 remissions (CR), 177 mild-moderate (CM) and 99 severe (CS) disease states. Gene and pathway composition was assessed using PICRUSt2 analyses of 16S data.

Results

As expected, changes in alpha and beta diversity, in interaction networks and increases in Proteobacteria abundance were associated with disease severity. However, microbial function was more consistently disrupted than composition from CR, to CM and then to CS. Major shifts in oxidative stress pathways and reduced carbohydrate and amino acid metabolism in favour of nutrient transport were identified in CS compared to CR. Virulence factors involved in host invasion, host evasion and inflammation were also increased in CS.

Conclusions

This functional metagenomic information provides new insights into community-wide microbial processes and pathways associated with CD pathogenesis. This study paves the way for new advanced strategies to rebalance gut microbiota and/or eliminate oxidative stress, and biofilm to downregulate gut inflammation.

Heat-inactivated Lactobacillus casei strain GKC1 Mitigates osteoporosis development in vivo via enhanced osteogenesis

Osteoporosis, a significant bone disease predominantly affecting elderly and postmenopausal women, leads to increased bone fragility and fracture risk, presenting a major public health concern with substantial socioeconomic implications. This study investigated the therapeutic potential of Lactobacillus strains, known for their immunomodulatory properties, in an ovariectomy-induced osteoporosis mouse model. Among three tested strains Lactobacillus casei GKC1, Lactobacillus rhamnosus GKLC1, and Lactobacillus johnsonii GKJ2, GKC1 demonstrated superior efficacy in promoting osteogenesis-related gene expression, including alkaline phosphatase (ALP), bone morphogenetic protein 2 (BMP2) and runt-related transcription factor 2 (RUNX2). In ovariectomized mice (n = 8/group), both live and heat-inactivated GKC1 (57 mg/kg) and fermented GKC1 (1000 mg/kg) were administered orally for 28 days, with alendronate (2.5 mg/kg) serving as a positive control. The treatment significantly improved bone mineral density and femoral microstructure parameters compared to the ovariectomized control group. For the first time, heat-inactivated GKC1 exhibited superior anti-inflammatory effects through reduction of IL-17A and enhanced bone microstructural integrity, suggesting its potential as a safe and effective therapeutic agent for postmenopausal osteoporosis management. These findings provide compelling evidence for the development of postbiotic-based interventions in osteoporosis treatment, offering a promising alternative to conventional therapeutics.

Association Between Genetically Proxied SLC12A2 Inhibition and Inflammatory Bowel Disease: A Mendelian Randomization Study

The global rise in hypertension prompts the use of medications to manage blood pressure. However, selecting first-line drugs remains challenging as their efficacy often stems from blood pressure reduction rather than specific pharmacological actions. Evaluating interactions between antihypertensive drugs and common diseases can aid tailored treatment. Here, we assess the potential link between antihypertensives and inflammatory bowel disease (IBD). Summary-level coronary heart disease (CHD) data (184,305 individuals), systolic BP (SBP) data (757,601 individuals), ulcerative ileocolitis data (361,188 individuals), ulcerative colitis data (364,454 individuals), other ulcerative colitis data (361,619 individuals), and ulcerative proctitis data (361,700 individuals) were all from genome-wide association studies (GWASs), FinnGen or eQTL studies publicly accessible. The DrugBank10 and ChEMBL11 databases function to identify genes encoding protein products targeted by active constituents of BP-lowering drugs. Summary-data-based MR (SMR) estimated the associations between expressions of drug target genes and symptoms of IBD. A multivariable MR study was further conducted to examine if the observed association was direct association. Subsequently, we collected blood samples from IBD patients in the Gastroenterology Department of Gastroenterology, the First Affiliated Hospital of Anhui Medical University and blood from healthy individuals at the physical examination center. Real-time quantitative PCR was employed to detect the expression changes of drug target genes in the peripheral blood of patients with IBD. Furthermore, we used Caco2 cells to construct an in vitro model of IBD, examined the expression of the target molecules, and verified the potential of Bumetanide to improve IBD. SMR analysis revealed that enhanced SLC12A2 gene expression in blood (equivalent to a one standard deviation increase) was a risk factor for ulcerative ileocolitis (beta = 0.5861, se = 0.2972, p = 0.0486) and enhanced gene expression of ACE was a protective factor. Additionally, SCNN1D and SLC16A1 played protective roles of IBD, while NR3C1 was identified as a risk factor. However, among these genes, only SLC12A2 was considered to influence the progress of inflammatory bowel disease through systolic blood pressure based on Mendelian randomization analysis results. Other genes may be associated with IBD depending on the expression of their own proteins, independent of changes in blood pressure. In the peripheral blood of IBD patients and in vitro experiments, SCL12A2 has been shown to be highly expressed in IBD. In vitro experiments have confirmed that Bumetanide can inhibit SCL12A2 to improve tight junctions, reduce inflammation levels, and ameliorate IBD symptoms. Therapeutic inhibition of SCL12A2 may benefit patients with IBD. In the future, this study may contribute to the selection of more personalized antihypertensive medications for different subgroups of hypertensive patients.

Open Label Vancomycin in Primary Sclerosing Cholangitis-Inflammatory Bowel Disease: Improved Colonic Disease Activity and Associations With Changes in Host-Microbiome-Metabolomic Signatures

BACKGROUND

We conducted a single-arm interventional study, to explore mucosal changes associated with clinical remission under oral vancomycin (OV) treatment, in primary sclerosing cholangitis-associated inflammatory bowel disease (PSC-IBD); NCT05376228.

METHODS

Fifteen patients with PSC and active colitis (median fecal calprotectin 459 µg/g; median total Mayo score 5) were treated with OV (125 mg QID) for 4 weeks and followed-up for a further 4 weeks of treatment withdrawal (8 weeks, end-of-study). Colonic biopsies were obtained at baseline and Week 4. Clinical assessments, and serum and stool samples (metagenomics, metatranscriptomics, and metabolomics) were collected at Weeks 0, 2, 4, and 8. The primary efficacy outcome measure was the induction of clinical remission.

RESULTS

Oral vancomycin resulted in clinical remission in 12/15 patients and significant reductions in fecal calprotectin. Oral vancomycin was associated with reduced abundances of Lachnospiraceae, genera Blautia and Bacteroides; and enrichment of Enterobacteriaceae, and genera Veillonella, Akkermansia, and Escherichia. Oral vancomycin treatment was associated with the downregulation of multiple metatranscriptomic pathways (including short-chain fatty acid [SCFA] metabolism and bile acid [BA] biotransformation), along with host genes and multiple pathways involved in inflammatory responses and antimicrobial defence; and an upregulation of genes associated with extracellular matrix repair. Oral vancomycin use resulted in the loss of specific fecal SCFAs and secondary BAs, including lithocholic acid derivatives. Colitis activity relapsed following OV withdrawal, with host mucosal and microbial changes trending toward baseline.

CONCLUSIONS

Four weeks of OV induces remission in PSC-IBD activity, associated with a reduction in gut bacterial diversity and compositional changes relating to BA and SCFA homeostasis.

A pro-inflammatory diet is associated with growth and virulence of Escherichia coli in pediatric Crohn's disease

BACKGROUND AND AIMS

Epidemiological studies have suggested an association between the inflammatory potential of dietary patterns and Crohn's disease (CD). However, the relationships of these inflammatory dietary determinants with the microbiome remain largely unknown. In this cross-sectional study, we evaluate the association between the inflammatory potential of habitual diet, as assessed by the modified Children-Dietary Inflammatory Index (mC-DII), and the fecal microbiome and metabolome of children with CD in comparison to healthy children.

METHODS

A cross-sectional study including 51 children with CD between 6 and 18 years of age and 50 healthy controls was conducted. Dietary inflammatory potential was measured using the mC-DII, and diet quality was assessed by the Healthy Eating Index (HEI)-2015 and alternate Mediterranean Eating Index (aMed). The microbiome was analyzed using shotgun metagenomic sequencing and untargeted metabolomic analysis.

RESULTS

A poor-quality, pro-inflammatory diet, with similar mC-DII, HEI-2015, and aMed scores, was found across healthy children and children with CD. In children with active disease, a pro-inflammatory diet was associated with decreased diversity, increased virulence potential, and expansion of the Proteobacteria phylum dominated by Escherichia coli (E. coli) spp. A positive correlation between E. coli relative abundance and mC-DII was associated with a low intake of a cluster composed of fibers, vitamins, and minerals with anti-inflammatory potential. A negative association between metabolites of fatty acid metabolism and HEI was found.

CONCLUSIONS

In total, our results suggest that a pro-inflammatory diet may potentiate hallmarks of the inflammation-associated dysbiosis in CD and highlight the need for microbiome-targeted dietary interventions optimizing the anti-inflammatory potential of habitual diet in the management of pediatric CD.

Retrograded starch as colonic delivery carrier of taxifolin for treatment of DSS-induced ulcerative colitis in mice

Taxifolin, a natural dihydroflavonol compound, possesses notable anti-inflammatory properties and regulatory effects on intestinal microbiota. In this study, gelatinized-retrograded corn starch (GCS) was utilized as a carrier for colonic delivery of taxifolin, and its therapeutic efficacy against dextran sulfate sodium (DSS)-induced colitis in mice were systematically investigated. Taxifolin can integrate into the helical structure of starch, and the formation of GCS-Taxifolin complexes (GCS-Tax) significantly delayed the release of taxifolin in vitro. After oral administration of GCS-Tax, fecal excretion of taxifolin increased from 0.42 % to 10.89 % within 24 h compared to free taxifolin. Moreover, GCS-Tax facilitated the production of short-chain fatty acid in mice and effectively alleviated DSS-induced colitis symptoms, including weight loss, bloody stools, and colonic tissue damage. Additionally, GCS-Tax significantly suppressed proinflammatory factors such as interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and lipopolysaccharide (LPS), while elevating anti-inflammatory interleukin-10 (IL-10) level in mice serum. Furthermore, it restored intestinal mucosal barrier function by upregulating the expression of Mucin 2, Occludin, and zonula occludens-1 (ZO-1), reducing Beclin 1 expression, and exhibited hepatoprotective effects by enhancing total antioxidant capacity (T-AOC), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activities. High-throughput sequencing analysis revealed that GCS-Tax improved intestinal flora diversity, reducing inflammation-related Bacterium 1 and Staphylococcus, while promoting the abundance of beneficial bacteria like Lachnospiraceae.

Transcriptomics and metabolomics reveal the alleviation effect of pectic polysaccharide on dextran sodium sulfate-induced colitis mice

Ulcerative colitis (UC) is a relapsing disease with an increasing morbidity and prevalence. Dietary polysaccharides have recently become a research hotspot because of their therapeutic effects and safety on UC. Our previous research elucidated that pectic polysaccharide from Phyllanthus emblica L. (PEP-1) could alleviate dextran sodium sulfate-induced UC mice. Herein, metabolomics and transcriptomics were further applied to disclose the underlying mechanisms behind PEP-1's anti-inflammatory effects. PEP-1 intervention altered the serum metabolite contents and pathways represented by decreasing xanthine and sphinganine levels. Changes in gene expressions correlated with metabolite variations led by the suppression of the expression of the inflammatory factors, colorectal cancer promoter, and NF-κB pathway as well as the enhancement of tight junctions. This study demonstrated that the ameliorating effect of chronic UC was partially ascribed to the alteration of the serum metabolites and changes in gene expression.

Protective effects and mechanisms of extracts of Gleditsia sinensis Lam. Thorn on DSS-induced colitis in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Inflammatory Bowel Disease (IBD), encompassing Ulcerative Colitis (UC) and Crohn's Disease (CD), stems from a multifaceted interaction of hereditary, immunological, ecological, and microbial elements. Current treatments have limitations, necessitating new therapeutic approaches.

AIM OF THE STUDY

This study investigates the safeguarding impacts and fundamental processes of extracts of Gleditsia sinensis Lam. thorn (EGST) in a dextran sulfate sodium (DSS)-induced colitis model in mice.

MATERIALS AND METHODS

A total of 180g of dried EGST were prepared, and untargeted metabolomic profiling using high-resolution liquid chromatography electrospray ionization orbitrap mass spectrometry (HR-LC-ESI-Orbitrap-MS) identified 930 compounds. UC model mice were administered 3% DSS for 7 d, followed by EGST treatment. The analysis encompassed physiological and pathological evaluations, serum cytokine ELISA, gut microbiota (GM) metagenomic sequencing, GC-MS metabolomics, mRNA sequencing, and Western Blot.

RESULTS

EGST markedly mitigated colitis symptoms, evidenced by reduced weight loss, lower DAI scores, and less colon shortening. It also decreased levels of pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) while boosting IL-10. Histological examination revealed diminished tissue damage, restoration of crypts, and reduced inflammation, with barrier integrity maintained via upregulation of occludin and ZO-1. Metagenomic sequencing demonstrated that EGST modulated the GM, enhancing the levels of Firmicutes and Bacteroidetes while reducing the levels of Proteobacteria and Verrucomicrobia. Metabolomic analysis indicated that EGST influenced critical pathways, including those involving D-amino acids, glutathione, cysteine, and methionine metabolism. Furthermore, mRNA sequencing identified 2625 differentially expressed genes (DEGs), comprising 1729 with increased and 896 with decreased expression, and highlighted EGST's impact on the PPARγ/AMPK/NF-κB pathway.

CONCLUSION

Overall, EGST mitigates DSS-induced colitis through modulation of GM, metabolic profiles, and gene expression, suggesting its promise as a naturally derived treatment for colitis.

Bile acids as signaling molecules in inflammatory bowel disease: Implications for treatment strategies

ETHNOPHARMACOLOGICAL RELEVANCE

Inflammatory bowel disease (IBD) is a globally increasing disease. Despite continuous efforts, the clinical application of treatment drugs has not achieved satisfactory success and faces limitations such as adverse drug reactions. Numerous investigations have found that the pathogenesis of IBD is connected with disturbances in bile acid circulation and metabolism. Traditional Chinese medicine targeting bile acids (BAs) has shown significant therapeutic effects and advantages in treating inflammatory bowel disease.

AIM OF THIS REVIEW

IThis article reviews the role of bile acids and their receptors in IBD, as well as research progress on IBD therapeutic drugs based on bile acids. It explores bile acid metabolism and its interaction with the intestinal microbiota, summarizes clinical drugs for treating IBD including single herbal medicine, traditional herbal prescriptions, and analyzes the mechanisms of action in treating IBD.

MATERIALS AND METHODS

IThe electronic databases such as PubMed, Web of Science, and China National Knowledge Infrastructure (CNKI) have been utilized to retrieve relevant literature up to January 2024, using keywords "bile acid", "bile acid receptor", "inflammatory bowel disease", "intestinal microbiota" and "targeted drugs".

RESULTS

IImbalance in bile acid levels can lead to intestinal inflammation, while IBD can disrupt the balance of microbes, result in alterations in the bile acid pool's composition and amount. This change can damage of intestinal mucosa healing ability. Bile acids are vital for keeping the gut barrier function intact, regulating gene expression, managing metabolic equilibrium, and influencing the properties and roles of the gut's microbial community. Consequently, focusing on bile acids could offer a potential treatment strategy for IBD.

CONCLUSION

IIBD can induce intestinal homeostasis imbalance and changes in BA pool, leading to fluctuations in levels of relevant metabolic enzymes, transporters, and nuclear receptors. Therefore, by regulating the balance of BA and key signaling molecules of bile acids, we can treat IBD. Traditional Chinese medicine has great potential and promising prospects in treating IBD. We should focus on the characteristics and advantages of Chinese medicine, promote the development and clinical application of innovative Chinese medicine, and ultimately make Chinese medicine targeting bile acids the mainstream treatment for IBD.

Impact of microplastics on the human digestive system: From basic to clinical

As a new type of pollutant, the harm caused by microplastics (MPs) to organisms has been the research focus. Recently, the proportion of MPs ingested through the digestive tract has gradually increased with the popularity of fast-food products, such as takeout. The damage to the digestive system has attracted increasing attention. We reviewed the literature regarding toxicity of MPs and observed that they have different effects on multiple organs of the digestive system. The mechanism may be related to the toxic effects of MPs themselves, interactions with various substances in the biological body, and participation in various signaling pathways to induce adverse reactions as a carrier of toxins to increase the time and amount of body absorption. Based on the toxicity mechanism of MPs, we propose specific suggestions to provide a theoretical reference for the government and relevant departments.

Role of the gut microbiome in psychological symptoms associated with inflammatory bowel diseases

The brain-gut axis constitutes the basis for the bidirectional communication between the central nervous system and the gastrointestinal tract driven by neural, hormonal, metabolic, immunological, and microbial signals. Alterations in the gut microbiome composition as observed in inflammatory bowel diseases can modulate brain function and emerging empirical evidence has indicated that interactions among the brain-gut microbiome-axis seem to play a significant role in the pathogenesis of both inflammatory bowel diseases and psychiatric disorders and their comorbidity. Yet, the immunological and molecular mechanisms underlying the co-occurrence of inflammatory bowel diseases and psychological symptoms are still poorly understood. The aim of this narrative review is to highlight contemporary empirical findings supporting a pivotal role of the gut microbiome in the pathophysiology of highly prevalent neuropsychiatric symptoms in inflammatory bowel diseases such as fatigue, depression, and anxiety. Finally, we focus on microbiome modulation as potential treatment option for comorbid neuropsychiatric symptoms in immune-mediated diseases and especially in inflammatory bowel diseases. High-quality clinical trials are required to clarify how microbiome modulation through dietary interventions or probiotic, prebiotic or synbiotic treatment can be used clinically to improve mental health and thus quality of life of patients with inflammatory bowel diseases.

Formulation, optimisation, and evaluation of Lornoxicam-loaded Novasomes for targeted ulcerative colitis therapy: in vitro and in vivo investigations

The purpose of this work was to create and assess Lornoxicam (LOR) loaded Novasomes (Novas) for the efficient treatment of ulcerative colitis. The study was performed using a 23 factorial design to investigate the impact of several formulation variables. Three separate parameters were investigated: Surface Active agent (SAA) type (X1), LOR concentration (X2), and SAA: Oleic acid ratio (X3). The dependent responses included encapsulation efficiency (Y1: EE %), particle size (Y2: PS), zeta potential (Y3: ZP), and polydispersity index (Y4: PDI). The vesicles demonstrated remarkable LOR encapsulation efficiency, ranging from 81.32 ± 3.24 to 98.64 ± 0.99%. The vesicle sizes ranged from 329 ± 9.88 to 583.4 ± 9.04 nm with high negative zeta potential values. The release pattern for Novas' LOR was biphasic and adhered to Higuchi's model. An in-vivo study assessed how LOR-Novas affected rats' acetic acid-induced ulcerative colitis (UC). The optimised LOR-Novas effectively reduced colonic ulceration (p < 0.05) and reduced the inflammatory pathway via inhibiting Toll-like receptor 4 (TLR4), Nuclear factor kappa β (NF-κβ) and inducible nitric oxide (iNO). At the same time, it elevated Silent information regulator-1(SIRT-1) and reduced glutathione (GSH) colon contents. Thus, the current study suggested that the formulation of LOR-Novas may be a viable treatment for ulcerative colitis.

Microbiome characterization of patients with Crohn disease and the use of fecal microbiota transplantation: A review

Inflammatory bowel disease is a chronic inflammatory condition predominantly affecting the intestines, encompassing both ulcerative colitis and Crohn disease (CD). As one of the most common gastrointestinal disorders, CD's pathogenesis is closely linked with the intestinal microbiota. Recently, fecal microbiota transplantation (FMT) has gained attention as a potential treatment for CD, with the effective reestablishment of intestinal microecology considered a crucial mechanism of FMT therapy. This article synthesizes the findings of population-based cohort studies to enhance our understanding of gut microbial characteristics in patients with CD. It delves into the roles of "beneficial" and "pathogenic" bacteria in CD's development. This article systematically reviews and compares data on clinical response rates, remission rates, adverse events, and shifts in bacterial microbiota. Among these studies, gut microbiome analysis was conducted in only 7, and a single study examined the metabolome. Overall, FMT has demonstrated a partial restoration of typical CD-associated microbiological alterations, leading to increased α-diversity in responders and a moderate shift in patient microbiota toward the donor profile. Several factors, including donor selection, delivery route, microbial state (fresh or frozen), and recipient condition, are identified as pivotal in influencing FMT's effectiveness. Future prospective clinical studies with larger patient cohorts and improved methodologies are imperative. In addition, standardization of FMT procedures, coupled with advanced genomic techniques such as macroproteomics and culture genomics, is necessary. These advancements will further clarify the bacterial microbiota alterations that significantly contribute to FMT's therapeutic effects in CD treatment, as well as elucidate the underlying mechanisms of action.

Studies on the alleviating effect of Bifidobacterium lactis V9 on dextran sodium sulfate-induced colitis in mice

Background

Inflammatory bowel disease (IBD) has become a global public health problem with complex pathogenesis and limited therapeutic options. We aimed to investigate the potential mechanisms by which Bifidobacterium lactis V9 (V9) alleviated colitis in a dextran sodium sulfate-induced colitis model mice.

Methods

Mice were induced to develop colitis by drinking DSS solution to induce colitis. The expression of the relevant factors in the blood supernatant of the mice was determined by ELISA. RT-qPCR and Western blotting were used to detect mRNA and protein expression of target genes. The fecal microbiota was analyzed by 16S rRNA sequencing. Intestinal metabolites were analyzed by untargeted metabolomics.

Results

V9 effectively improved the overall symptoms of the colitis model mice. H&E showed that V9 re-stored the intestinal tissue structure. ELISA showed that V9 decreased the levels of IL-6, IL-22, and TNF-α and increased IL-10, SP, VIP, and 5-HT. V9 increased the expression of AHR, CYP1A1, MUC2, Claudin-3, Occludin, and ZO-1, and decreased 5-hydroxytryptamine transporter and Claudin-2. V9 increased the abundance of gut microbiota in colitis mice to promote the growth of beneficial bacteria. V9 increased tryptophan metabolites, and short-chain fatty acids, and improved gut inflammation.

Conclusion

V9 attenuates intestinal inflammation, improves the mucosal barrier, modulates intestinal microecology and exerts a protective effect in a mouse model of DSS-induced colitis.

Case report: A co-existing case of ulcerative colitis and dysferlinopathy in a male patient

Patients with inflammatory bowel disease (IBD) are at risk of developing malnutrition, severe dystrophic muscle weakness, and muscle atrophy. We present a case of a 33-year-old male patient who exhibited concurrent muscle atrophy, muscle weakness, diarrhea, and mucopurulent bloody stools. Notably, the patient reported that his household or family members experienced similar symptoms of muscle weakness, without any apparent neurological or psychiatric manifestations. The patient's intestinal symptoms were most consistent with ulcerative colitis, while the muscle weakness originated from dysferlinopathy following a comprehensive diagnostic work-up. The patient was initiated on vedolizumab therapy and L-carnitine therapy, and his symptoms improved after 1 month of follow-up. This case study underscores the necessity for clinicians to maintain a high level of suspicion for the presence of concomitant diseases when encountering IBD patients with muscle weakness. This approach is essential for achieving an early diagnosis and treatment.

Acute stress triggers sex-dependent rapid alterations in the human small intestine microbiota composition

Background/aims

Digestive disorders of gut-brain interaction (DGBI) are very common, predominant in females, and usually associated with intestinal barrier dysfunction, dysbiosis, and stress. We previously found that females have increased susceptibility to intestinal barrier dysfunction in response to acute stress. However, whether this is associated with changes in the small bowel microbiota remains unknown. We have evaluated changes in the small intestinal microbiota in response to acute stress to better understand stress-induced intestinal barrier dysfunction.

Methods

Jejunal biopsies were obtained at baseline and 90 min after cold pain or sham stress. Autonomic (blood pressure and heart rate), hormonal (plasma cortisol and adrenocorticotropic hormone) and psychological (Subjective Stress Rating Scale) responses to cold pain and sham stress were monitored. Microbial DNA from the biopsies was analyzed using a 16S metabarcoding approach before and after cold pain stress and sham stress. Differences in diversity and relative abundance of microbial taxa were examined.

Results

Cold pain stress was associated with a significant decrease in alpha diversity (P = 0.015), which was more pronounced in females, along with significant sex differences in the abundance of specific taxa and the overall microbiota composition. Microbiota alterations significantly correlated with changes in psychological responses, hormones, and gene expression in the intestinal mucosal. Cold pain stress was also associated with activation of autonomic, hormonal and psychological response, with no differences between sexes.

Conclusions

Acute stress elicits rapid alterations in bacterial composition in the jejunum of healthy subjects and these changes are more pronounced in females. Our results may contribute to the understanding of female predominance in DGBI.

Deer oil improves ulcerative colitis induced by DSS in mice by regulating the intestinal microbiota and SCFAs metabolism and modulating NF-κB and Nrf2 signaling pathways

BACKGROUND

Deer oil (DO), a byproduct of deer meat processing, possesses high nutritional value. This study aims to evaluate the protective effects of DO on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice and to explore its potential mechanisms of action.

RESULTS

DO was found to inhibit weight loss and colon shortening in colitis mice, significantly reduce disease activity index scores, and notably enhance the levels of tight junction proteins in colon tissues, thus improving intestinal barrier function. ELISA results indicated that DO markedly alleviated the mice's oxidative stress and inflammatory responses. Western blot analysis further demonstrated that DO significantly inhibited the phosphorylation of NF-κB while up-regulating the expression levels of Nrf2 and HO-1 proteins. Additionally, DO increased the abundance of beneficial bacteria such as Odoribacter, Blautia, and Muribaculum, reduced the abundance of harmful bacteria such as Bacteroides, Helicobacter, and Escherichia-Shigella, and promoted the production of short-chain fatty acids.

CONCLUSION

Our study provides the first evidence that DO can effectively improve DSS-induced UC in mice. The underlying mechanisms may involve maintaining intestinal barrier function, inhibiting inflammation, alleviating oxidative stress, and modulation of gut microbiota. These findings offer valuable insights for developing DO as an adjunct treatment for UC and as a functional food. © 2024 Society of Chemical Industry.

Bowel preparation before colonoscopy: Consequences, mechanisms, and treatment of intestinal dysbiosis

The term "gut microbiota" primarily refers to the ecological community of various microorganisms in the gut, which constitutes the largest microbial community in the human body. Although adequate bowel preparation can improve the results of colonoscopy, it may interfere with the gut microbiota. Bowel preparation for colonoscopy can lead to transient changes in the gut microbiota, potentially affecting an individual's health, especially in vulnerable populations, such as patients with inflammatory bowel disease. However, measures such as oral probiotics may ameliorate these adverse effects. We focused on the bowel preparation-induced changes in the gut microbiota and host health status, hypothesized the factors influencing these changes, and attempted to identify measures that may reduce dysbiosis, thereby providing more information for individualized bowel preparation for colonoscopy in the future.

Potential role of gut-related factors in the pathology of cartilage in osteoarthritis

Osteoarthritis (OA) is a common progressive degenerative disease. Gut microbiota (GM) and their metabolites have been closely associated with the onset, progression, and pathology of OA. GM and their metabolites may influence the cartilage directly, or indirectly by affecting the gut, the immune system, and the endocrine system. They function through classical pathways in cartilage metabolism and novel pathways that have recently been discovered. Some of them have been used as targets for the prevention and treatment of OA. The current study sought to describe the major pathological signaling pathways in OA chondrocytes and the potential role of gut-related factors in these pathways.

Probiotic Bacillus pumilus LV149 enhances gut repair, modulates microbiota, and alters transcriptome in DSS-induced colitis mice

Purpose

Gut microbiota dysbiosis significantly impacts ulcerative colitis (UC) progression and exacerbation. Probiotics show promise in UC management. This study evaluated the effects of different doses of Bacillus pumilus LV149, an aquatic-derived probiotic, on gut injury repair in male C57BL/6 mice with dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) and investigated the underlying mechanisms.

Methods

UC was induced by allowing mice free access to a 3% DSS solution for 7 days, with concurrent daily oral gavage of either a low (LV149-L, 1 × 108 CFU/day/mouse) or high (LV149-H, 1 × 109 CFU/day/mouse) dose of LV149. The effects were assessed through physiological parameters, intestinal barrier integrity, inflammation, gut microbiota composition, and transcriptomic changes.

Results

LV149 significantly improved pathological symptoms, including weight loss and disease activity index (DAI), and reduced colon shortening in a dose-dependent manner and inflammatory damage. The intervention also restored gut barrier function by upregulating mucins, goblet cell counts, and tight junction proteins (ZO-1, occludin, and claudin-1) in colonic tissue, along with reducing serum lipopolysaccharide (LPS) levels. Notably, only the LV149-H significantly decreased the expression of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6, while both doses increased the expression of the anti-inflammatory cytokine IL-10 in a dose-dependent in colonic tissue. LV149 further modulated the gut microbiota, increasing beneficial bacteria and reducing pathogenic populations. Transcriptomic analysis indicated that LV149-L may exert gut repair effects via the IL-17 signaling pathway, whereas LV149-H appears to act through the JAK-STAT signaling pathway.

Conclusion

This study demonstrated that LV149, particularly at a higher dose, effectively mitigated DSS-induced colonic injury by modulating gut microbiota, enhancing gut barrier integrity, and reducing inflammation. The dose-dependent effects underscored LV149-H's potential as a therapeutic agent for UC due to its stronger anti-inflammatory properties and gut-protective effects.

Metagenomic characterization of oral microbiome signatures to predict upper gastrointestinal and pancreaticobiliary cancers: a case-control study

BACKGROUND

This study investigated the oral microbiome signatures associated with upper gastrointestinal (GI) and pancreaticobiliary cancers.

METHODS

Saliva samples from cancer patients and age- and sex-matched healthy controls were analyzed using 16S rRNA-targeted sequencing, followed by comprehensive bioinformatics analysis.

RESULTS

Significant dissimilarities in microbial composition were observed between cancer patients and controls across esophageal cancer (EC), gastric cancer (GC), biliary tract cancer (BC), and pancreatic cancer (PC) groups (R2 = 0.067, = 0.075, = 0.068, and = 0.044; p = 0.001, = 0.001, = 0.002, and = 0.004, respectively). Additionally, the oral microbiome composition significantly differed by the four cancer sites (p = 0.001 for EC vs. GC, EC vs. BC, EC vs. PC, GC vs. BC, and GC vs. PC; p = 0.013 for BC vs. PC). We built oral metagenomic classifiers to predict cancer and selected specific microbial taxa with diagnostic properties. For EC, the classifier differentiated cancer patients and controls with good accuracy (area under the curve [AUC] = 0.791) and included three genera: Akkermansia, Escherichia-Shigella, and Subdoligranulum. For GC, the classifier exhibited high discriminative power (AUC = 0.961); it included five genera (Escherichia-Shigella, Gemella, Holdemanella, Actinomyces, and Stomatobaculum) and three species (Eubacterium sp. oral clone EI074, Ruminococcus sp. Marseille-P328, and Leptotrichia wadei F0279). However, microbial taxa with diagnostic features for BC and PC were not identified.

CONCLUSIONS

These findings suggested that the oral microbiome composition may serve as an indicator of tumorigenesis in upper GI and pancreaticobiliary cancers. The development of oral metagenomic classifiers for EC and GC demonstrates the potential value of microbial biomarkers in cancer screening.

Combining vitamin E metabolite 13'-carboxychromanol and a lactic acid bacterium synergistically mitigates colitis and colitis-associated dysbiosis in mice

Synbiotics may be useful to mitigate intestinal diseases such as ulcerative colitis. Here we show that combining 13'-carboxychromanol (δT3-13'), a metabolite of vitamin E δ-tocotrienol (δT3) via omega-oxidation, and Lactococcus lactis subsp. cremori (L. cremoris), but neither agent alone, significantly attenuated dextran sulfate sodium (DSS)-induced fecal bleeding and diarrhea, histologic colitis and interleukin 1β in mice. The combination of δT3-13'+L. cremoris also synergistically prevented DSS-caused compositional changes in gut microbiota and enriched beneficial bacteria including Lactococcus and Butyricicoccus. Interestingly, the anti-colitis effect correlated with the concentrations of δT3-13'-hydrogenated metabolite that contains 2 double bonds on the side chain (δT2-13'), instead of δT3-13' itself. Moreover, in contrast to δT3-13', combining δT3 and L. cremoris showed modest anti-colitis effects and did not prevent colitis-associated dysbiosis. In addition, ex vivo anaerobic incubation studies revealed that gut microbes selected by δT3-13' in the animal study could metabolize this compound to δT2-13' via hydrogenation, which appeared to be enhanced by L. cremoris. Overall, our study demonstrates that combining δT3-13' and L. cremoris can synergically prevent dysbiosis, and may be a novel synbiotic against colitis potentially via promoting δT3-13' metabolizers, which in turn contributes to superior beneficial effects of the combination.

Gut microbial dysbiosis and inflammation: Impact on periodontal health

Periodontitis is widely acknowledged as the most prevalent type of oral inflammation, arising from the dynamic interplay between oral pathogens and the host's immune responses. It is also recognized as a contributing factor to various systemic diseases. Dysbiosis of the oral microbiota can significantly alter the composition and diversity of the gut microbiota. Researchers have delved into the links between periodontitis and systemic diseases through the "oral-gut" axis. However, whether the associations between periodontitis and the gut microbiota are simply correlative or driven by causative mechanistic interactions remains uncertain. This review investigates how dysbiosis of the gut microbiota impacts periodontitis, drawing on existing preclinical and clinical data. This study highlights potential mechanisms of this interaction, including alterations in subgingival microbiota, oral mucosal barrier function, neutrophil activity, and abnormal T-cell recycling, and offers new perspectives for managing periodontitis, especially in cases linked to systemic diseases.