Search Results (155)

Background: Airway mucus plugging is a key but long-overlooked mechanism of persistent airflow obstruction in both asthma and chronic obstructive pulmonary disease (COPD). Type 2 (T2) cytokines, particularly interleukin (IL)-4 and IL-13, drive goblet cell metaplasia, MUC5AC overexpression, and impaired mucociliary clearance, while eosinophil-derived products increase mucus viscosity and promote plug persistence. Methods: A comprehensive narrative review was conducted by searching PubMed and ClinicalTrials.gov databases from inception to February 2026. Search terms included “mucus plugs,” “mucus plugging,” “biologics,” “dupilumab,” “tezepelumab,” “mepolizumab,” “benralizumab,” “IL-4,” “IL-13,” “MUC5AC,” “quantitative CT,” “functional respiratory imaging,” “asthma,” and “COPD.” Studies were included if they reported original data or systematic evidence on mucus plug quantification, biologic-mediated changes in mucus plug scores, or imaging modalities for mucus assessment in asthma or COPD. Editorials, case reports with fewer than three patients, and studies not available in English were excluded. Two authors (P.-V.M. and A.C.) independently screened titles and abstracts; discrepancies were resolved by consensus. Randomized controlled trials, observational studies, and preclinical studies evaluating mucus plug outcomes and T2-targeted therapies were included. Reference lists of retrieved articles were hand-searched for additional relevant publications. Results: A recent systematic review identified multiple randomized controlled trials and observational studies that showed CT-assessed mucus plug scores go down with biologic therapies targeting the T2 pathway in asthma. Observational data extend this evidence to anti-IL-5/IL-5Rα agents. The VESTIGE trial provided the first functional respiratory imaging evidence of mucus plug resolution with dupilumab. In COPD, the BOREAS/NOTUS and MATINEE trials established the efficacy of dupilumab and mepolizumab in eosinophilic phenotypes; however, differences in inclusion criteria—particularly regarding FeNO thresholds and prior exacerbation burden—may explain divergent effects on lung function endpoints. Mucus plug outcomes have not been evaluated in COPD biologic trials. Quantitative imaging modalities, including HRCT mucus plug scoring, functional respiratory imaging, and hyperpolarized gas MRI, now enable objective assessment of mucus burden. Conclusions: Mucus plugging meets the definition of a treatable trait: it can be measured with CT scoring, it matters clinically, and it responds to T2 cytokine blockade. Adding mucus plug assessment to routine clinical evaluation, together with mucolytic strategies where needed, could move treatment decisions from empirical to biology-based across the asthma–COPD spectrum. Further studies are needed to confirm that mucus plug scoring works as a biomarker of treatment response in COPD and to test whether combining biologics with mucolytics improves outcomes. Full article

Mucins are highly glycosylated proteins that form the structural basis of mucus and represent a key component of innate immunity at mucosal surfaces, particularly in the respiratory tract. Beyond their mechanical barrier function, mucins actively participate in pathogen trapping, regulation of mucociliary clearance, modulation of inflammatory responses, and maintenance of epithelial homeostasis. Dysregulation of mucin synthesis, composition, or transport contributes to mucus hypersecretion, impaired airway clearance, and chronic inflammation in respiratory diseases such as asthma, chronic obstructive pulmonary disease, and cystic fibrosis. This review summarizes current insights into mucin biology, including their biosynthesis, structure, classification, and regulation, with emphasis on the gel-forming mucins MUC5AC and MUC5B. The role of mucins in mechanical protection, host–pathogen interactions, control of inflammation, and coordination of innate immune responses is reviewed. Attention is given to the interplay between mucins, immune cells, and microbial communities in maintaining airway barrier integrity. The article further examines mucoactive therapeutic strategies aimed at restoring mucus barrier function. Expectorants, mucolytics, mucoregulators, and mucokinetic agents are reviewed with respect to their mechanisms of action and clinical relevance. Established drugs, including N-acetylcysteine, carbocysteine, dornase alfa, ambroxol, and hypertonic solutions, are considered alongside emerging molecular targets such as NF-κB-dependent regulation of mucin expression, calcium-activated chloride channels, MARCKS-mediated mucin exocytosis, purinergic signaling pathways, and NO/cGMP signaling. Non-pharmacological approaches, including airway clearance techniques and respiratory rehabilitation, are covered concisely. Conclusions: Overall, this review highlights mucins as dynamic regulators of innate immunity and underscores the need for mechanism-based, personalized mucoactive therapies to improve outcomes in chronic inflammatory airway diseases. Full article

Gastric-type lesions in the duodenum, including pyloric gland adenoma and gastric foveolar metaplasia, have been increasingly recognized for their unique histogenesis and potential link through the metaplasia–neoplasia sequence. However, the coexistence of neoplastic and non-neoplastic gastric-type lesions within the same histological section has not been previously reported. Here, we present a case of a 73-year-old Japanese woman who underwent endoscopic submucosal dissection for a 34 × 20 mm elevated lesion in the duodenal bulb. Based on the preoperative biopsy results, pyloric gland adenoma was diagnosed; however, histopathological examination of the resected specimen revealed a far more complex picture. The main lesion consisted of two contiguous components: a hyperplastic polyp with gastric foveolar-type phenotype (Lesion I) and a pyloric gland adenoma mixed with gastric foveolar-type hyperplastic polyp (Lesion II). Importantly, the transitional zone between these components demonstrated histological continuity, with areas showing admixture of hyperplastic and adenomatous features within the same microscopic field. A separate hyperplastic polyp with gastric foveolar-type phenotype (Lesion III) was also identified, separated from Lesions I and II by intervening normal duodenal mucosa. All lesions shared a gastric-type mucin phenotype (MUC5AC-positive, CD10-negative), and extensive Brunner’s gland hyperplasia was observed throughout the specimen. This case provides compelling morphological evidence for a histogenetic link between non-neoplastic gastric-type hyperplasia and pyloric gland adenoma, supporting the concept of a metaplasia–neoplasia sequence in the duodenum. Furthermore, the presence of an additional separate lesion with the same phenotype suggests a field change in the development of gastric-type lesions. Full article

Background: The progression of idiopathic pulmonary fibrosis (IPF) involves distal airway remodeling and bronchiolization; however, the mechanisms driving these changes, particularly the contributions of epithelial stem cells, are not fully understood. K13⁺ hillock cells, normally quiescent in proximal airways, were examined for their potential contribution to IPF pathogenesis. Methods: Spatial immunofluorescence was used to profile K13 expression along the airway axes in IPF and control lungs. Multiplex staining complemented by ex vivo culture assays was used to test expression stability. Single-cell RNA-sequencing (scRNA-seq) data were re-analyzed to identify cell subclusters and pathway enrichments. Meanwhile, cell–cell communication was inferred by using CellChat. Results: K13 was ectopically upregulated in IPF honeycomb cysts, triggering a proximal-like pseudostratified phenotype. This shift was marked by surges in K13⁺ regionally overlapping expression patterns (K5⁺, ~9%; CC10⁺, ~53%; ACE-TUB⁺, ~44%; MUC5AC⁺, ~23%) and a decline in SOX2 expression (~95% to ~64%), with ~70% of residual SOX2^low cells exhibiting elevated K13. Accompanying the expansion of K13⁺ subclusters (basal: 1.8% to 41.5%; club: 10.7% to 31.5%), it was observed that the profibrotic markers (K17, S100A2, LGALS7, IGFBP6) and ontologies related to RNA processing, stress response, and senescence were also enriched. These subclusters also amplified pro-fibrotic signaling (e.g., TGF-β, SEMA3, and GALECTIN-9) associated with epithelial subtypes and HAS1^high fibroblasts. Conclusions: Here, we demonstrate that K13⁺ cell activation is a pivotal event, driving the dysregulated proximalization of distal airways in IPF through fate reprogramming and epithelial-mesenchymal crosstalk. Thus, elucidating these K13-mediated fate dynamics provides a critical framework for understanding IPF pathogenesis. Full article

The cystic fibrosis transmembrane conductance regulator (CFTR) is a member of the atypical ATP-binding cassette (ABC) family that functions as a phosphorylation-regulated epithelial anion channel. Cystic fibrosis (CF) is characterised by variants in the CFTR gene that lead to impaired epithelial chloride–ion transport and increased mucus viscosity. Although CFTR modulators such as Trikafta^® have transformed the care of many CF patients, individuals harbouring rare CFTR variants still have no effective treatment options. In this study, we used primary air–liquid interface (ALI) airway cultures obtained from 21 CF patients (pwCF) and 21 healthy controls (HC) to evaluate the therapeutic efficacy of CFTR restoration based on chitosan-mediated CFTR mRNA and modulators. While modulators restored CFTR channel function in most cultures derived from CF patients, those with class I or other rare variants showed no improvement. Chitosan-mediated CFTR mRNA delivery successfully restored CFTR function in ALI cultures of patients carrying rare CFTR variants with limited or no observed clinical response to modulator therapy, assessed by electrophysiology using our newly developed Multi Transepithelial Current Clamp (MTECC) Ussing chamber. This was then confirmed by morphological visualisation of CFTR protein expression in modulator-responsive patient samples using immunofluorescence (IF) staining. IF revealed an increase in CFTR signal and the restoration of epithelial barrier integrity following chitosan-mRNA and modulator treatment as a secondary outcome alongside CFTR functional measurements. Notably, MUC5AC expression, a major gel-forming mucin expressed by airway goblet cells and mucus viscosity were elevated in CF cultures, but were markedly reduced following successful intervention, approaching the levels seen in HCs. These findings establish the potential of chitosan-mRNA delivery as a therapeutic approach for CF patients, particularly those who do not respond to modulators. They also provide a practical, comparative evaluation of advanced mRNA-based treatments in patient-derived airway models. Full article

This study investigates whether fecal microbiota transplantation (FMT) can alleviate gut microbiota dysbiosis induced by a high-fat diet (HFD) through modulation of fatty acid metabolism, competition for nutrients, production of short-chain fatty acids (SCFAs), and restoration of mucus layer integrity. To elucidate the mechanisms by which FMT regulates colonic microbial function and host metabolic responses, 80 male Bal b/c mice were randomly assigned to four experimental groups (n = 20 per group): Normal Diet Group (NDG), High-Fat Diet Group (HDG), Restrictive Diet Group (RDG), and HDG recipients of NDG-derived fecal microbiota (FMT group). The intervention lasted for 12 weeks, during which body weight was monitored biweekly. At the end of the experiment, tissue and fecal samples were collected to assess digestive enzyme activities, intestinal histomorphology, gene expression related to gut barrier function, and gut microbiota composition via 16S rRNA gene sequencing. Results showed that mice in the HDG exhibited significantly higher final body weight and greater weight gain compared to those in the NDG and RDG (p < 0.05). Notably, FMT treatment markedly attenuated HFD-induced weight gain (p < 0.05), reducing it to levels comparable with the NDG (p > 0.05). While HFD significantly elevated the activities of α-amylase and trypsin (p < 0.05), FMT supplementation effectively suppressed these enzymatic activities (p < 0.05). Moreover, FMT ameliorated HFD-induced intestinal architectural damage, as evidenced by significant increases in villus height and the villus height-to-crypt depth ratio (V/C) (p < 0.05). At the molecular level, FMT significantly downregulated the expression of pro-inflammatory cytokines (IL-1β, IL-1α, TNF-α) and upregulated key tight junction proteins (Occludin, Claudin-1, ZO-1) and mucin-2 (MUC2) relative to the HDG (p < 0.05). 16S rRNA analysis demonstrated that FMT substantially increased the abundance of beneficial genera such as Lactobacillus and Bifidobacterium while reducing opportunistic pathogens including Romboutsia (p < 0.05). Furthermore, alpha diversity indices (Chao1 and ACE) were significantly higher in the FMT group than in all other groups (p < 0.05), indicating enhanced microbial richness and community stability. Functional prediction using PICRUSt2 revealed that FMT-enriched metabolic pathways (particularly those associated with SCFA production) and enhanced gut barrier-related functions. Collectively, this study deepens our understanding of host–microbe interactions under HFD-induced metabolic stress and provides mechanistic insights into how FMT restores gut homeostasis, highlighting its potential as a therapeutic strategy for diet-induced dysbiosis and associated metabolic disorders. Full article

Background: Chronic obstructive pulmonary disease (COPD) is a progressive inflammatory lung disorder with limited effective therapies. NRICM102, a traditional multi-herbal formulation originally developed for COVID-19, exhibits anti-inflammatory and immunomodulatory potential. Objectives: The aim of this study was to investigate the therapeutic efficacy of NRICM102 in a COPD-relevant inflammatory lung injury mice model. Methods: Mice were exposed to lipopolysaccharide (LPS) and benzo[a]pyrene (B[a]P) to induce chronic airway inflammation and structural lung damage and treated with NRICM102 (1.5–3.0 g/kg) or dexamethasone. Lung function, histopathology, transcriptomic profiling, and protein expression of key inflammatory markers were assessed. Results: NRICM102 significantly restored LPS+B[a]P-induced enhanced pause (Penh) and arterial oxygen saturation (aO₂%), similar to the effect of dexamethasone. Histological analysis revealed marked alveolar damage, inflammatory cell infiltration, and fibrosis in the model group, all of which were significantly attenuated by NRICM102 in a dose-dependent manner, with high-dose (3.0 g/kg) treatment showing pronounced structural preservation. Transcriptomic profiling revealed that NRICM102, particularly at 3.0 g/kg, partially reversed COPD-associated gene expression patterns, characterized by reduced activation of cytokine signaling, chemokine activity, and antigen presentation pathways. GO, DO, and KEGG enrichment analyses indicated selective modulation of immune-related pathways, with high-dose NRICM102 affecting genes involved in adaptive immunity and cytokine receptor interactions, including a subset of 150 reverted genes. Immunofluorescence analysis confirmed dose-dependent reductions in key inflammatory, immune, and mucus-related markers, including IL-1β, NLRP3, Muc5ac, and MMP12 expression. Conclusions: NRICM102 confers significant protective effects against COPD-relevant inflammatory lung injury by improving pulmonary function, preserving lung architecture, and selectively modulating immune and inflammatory pathways. These results provide preclinical evidence supporting the potential of NRICM102 to modulate inflammation and immune responses associated with COPD-related pathology, although further studies are needed to establish its therapeutic relevance. Full article

Objectives: This study evaluated the effects of modified Gamchogeongang-tang (GGS01) on lung injury using a COPD mouse model. Methods: C57BL/6 mice were exposed to cigarette smoke extract and lipopolysaccharide and treated with GGS01 (100, 200, or 400 mg/kg). Bronchoalveolar lavage fluid (BALF) and lung tissue were analyzed using cytospin, enzyme-linked immunosorbent assay, real-time polymerase chain reaction (PCR), flow cytometry analysis, hematoxylin and eosin (H&E) and Masson’s trichrome staining, and immune histology fluorescent staining. Results: GGS01 significantly inhibited the increase in neutrophils in BALF, decreased immune cell activity in BALF and lung tissue, and inhibited the increase in the levels of IL-1α, TNF-α, IL-17A, MIP2, and CXCL-1 in BALF. Conclusions: Real-time PCR analysis showed that MUC5AC mRNA expression in lung tissue significantly decreased compared with the control group. The score of histological analysis of lung tissue damage was significantly reduced, and a decrease in IRAK1 and TNF-α expression in lung tissue was observed. Full article

Endometriosis (EM) is a chronic inflammatory disease characterized by the growth of endometrial-like tissue outside the uterus, yet its molecular mechanisms remain poorly understood. This study investigated the expression of mucins (MUC1, MUC2, MUC5AC, MUC6, MUC16) and their O-glycans in endometriotic lesions, given their roles in epithelial protection, adhesion, and immune modulation. Using immunohistochemistry, Western blotting, lectin profiling, histochemical staining, and transcriptomic analysis, we compared mucin levels and glycosylation patterns in eutopic and ectopic tissues from women with and without endometriosis and measured mucin-derived tumor markers in serum (CA 125/MUC16 and CA 15-3/MUC1) and peritoneal fluid (CA 125/MUC16). The results showed significant upregulation of all mucins in EM biopsies, with increased MUC1 transcript levels, while MUC6 and MUC16 protein levels did not always align with transcripts. Yet, tumor markers CA 125 and CA 15-3 showed no significant differences between groups. Looking at mucin distribution in biopsies of peritoneal (pEM), deep infiltrating and ovarian EM, MUC1 was significantly overexpressed in lesions of all EM forms, while MUC5AC was significantly elevated in pEM. Lectin analysis revealed specific glycan changes, including elevated core-1 O-glycans and α(1-2)-linked fucosylation, while sialylation remained unchanged. These findings demonstrate consistent mucin dysregulation and glycan alterations, implicating their roles in epithelial adhesion, immune evasion, and lesion persistence. Mucin biology thus emerges as a promising target for diagnostic and therapeutic strategies in endometriosis. Full article

Background: Galectin-10 (Gal-10), the main constituent of Charcot–Leyden crystals, is a recognized marker of eosinophilic inflammation, yet its role in nasal mucosal remodeling in Seasonal Allergic Rhinitis (SAR) remains poorly defined. Methods: Gal-10, IL-5, MUC5AC, and IFN-γ were analyzed in Nasal lavage (NL) samples from children with SAR by ELISA. Unsupervised clustering and discriminant analyses were applied. The functional effects of Gal-10 were investigated ex vivo using a 3D epithelial–mesenchymal trophic unit (EMTU) model stimulated with NL containing high, low, or depleted Gal-10 levels. EMT (epithelial–mesenchymal transition) markers (vimentin, E-cadherin, SNAIL1) and MUC5AC secretion were assessed by immunohistochemistry, Western blot, and ELISA. Results: Gal-10 levels in NL positively correlated with IL-5 and MUC5AC and inversely with IFN-γ. Clustering analysis identified distinct SAR endotypes, with Gal-10 showing the highest discriminative power. In the 3D EMTU model, high Gal-10 NL induced increased vimentin and SNAIL1 expression and enhanced MUC5AC secretion, effects attenuated after Gal-10 depletion. Conclusions: Gal-10 is associated with Th2-type inflammation, mucus hypersecretion, and early epithelial–mesenchymal transition in pediatric SAR, supporting its role as a mediator of nasal mucosal remodeling and a potential therapeutic target Full article

Personalized cancer vaccines are a key strategy for training the immune system to recognize and respond to tumor-specific antigens. Our earlier software release, AutoEpiCollect 1.0, was designed to accelerate the vaccine design process, but the identification of tumor-specific genetic variants remains a manual process and is highly burdensome. In this study, we introduce AutoEpiCollect 2.0, an improved version with integrated genetic analysis capabilities that automate the identification and prioritization of tumorigenic variants from individual tumor samples. AutoEpiCollect 2.0 connects with RNA sequencing and cross-references the resulting RNAseq data for efficient determination of cancer-specific and prognostic gene variants. Using AutoEpiCollect 2.0, we conducted two case studies to design personalized peptide vaccines for two distinct cancer types: cervical squamous cell carcinoma and breast carcinoma. Case 1 analyzed five cervical tumor samples from different stages, ranging from CIN1 to cervical cancer stage IIB. CIN3 was selected for detailed analysis due to its pre-invasive status and clinical relevance, as it is the earliest stage where patients typically present symptoms. Case 2 examined five breast tumor samples, including HER2-negative, ER-positive, PR-positive, and triple-negative subtypes. In three of these breast samples, the same epitope was identified and was synthesized by identical gene variants. This finding suggests the presence of shared antigenic targets across subtypes. We identified the top MHC class I and class II epitopes for both cancer types. In cervical carcinoma, the most immunogenic epitopes were found in proteins expressed by HSPG2 and MUC5AC. In breast carcinoma, epitopes with the highest potential were derived from proteins expressed by BRCA2 and AHNAK2. These epitopes were further validated through pMHC-TCR modeling analysis. Despite differences in cancer type and tumor subtype, both case studies successfully identified high-potential epitopes suitable for personalized vaccine design. The integration of AutoEpiCollect 2.0 streamlined the variant analysis workflow and reduced the time required to identify key tumor antigens. This study demonstrates the value of automated data integration in genomic analysis for cancer vaccine development. Furthermore, by applying RNAseq in a standardized workflow, the approach enables both patient-specific and population-level vaccine design, based on statistically frequent gene variants observed across tumor datasets. AutoEpiCollect 2.0 is freely available as a website based tool for user to design vaccine. Full article

Airborne particulate matter (PM), particularly PM_2.5, contributes to pulmonary injury by inducing oxidative stress and inflammation. Thyme (Thymus vulgaris L.) contains bioactive compounds with anti-inflammatory, antioxidant, and expectorant properties. Here, we evaluated the dose-dependent protective effects of thyme extract (TV) against PM_2.5-induced pulmonary injury in mice, using dexamethasone (DEXA) as a reference anti-inflammatory drug. Subacute pulmonary injury was induced in male Balb/c mice via intranasal administration of PM_2.5 (1 mg/kg, twice at 48 h intervals). Mice received oral TV (50, 100, or 200 mg/kg) or DEXA (0.75 mg/kg) daily for 10 days. Assessments included lung weight, serum AST/ALT, bronchoalveolar lavage fluid (BALF) leukocyte counts, cytokines (TNF-α, IL-6), chemokines, oxidative stress markers (ROS, lipid peroxidation, antioxidant enzymes), histopathology, and mRNA expression of genes related to inflammation (PI3K/Akt, MAPK, and NF-κB), mucus production (MUC5AC, MUC5B), and apoptosis (Bcl-2, Bax). Exposure to PM_2.5 caused oxidative stress, pulmonary inflammation, mucus hypersecretion, and histopathological changes. TV treatment dose-dependently reduced leukocyte infiltration, cytokine/chemokine release, ROS generation, and mucus overproduction, while enhancing antioxidant defenses and improving tissue pathology. Effects were comparable but slightly less potent than DEXA. Notably, unlike DEXA, TV reduced mucus hyperplasia and enhanced expectorant activity. No hepatotoxicity was observed. These results indicate that thyme extract could serve as a promising natural candidate for alternative respiratory therapeutics or functional food development. Full article

Centella asiatica, a widely used medicinal herb in Oriental and increasingly Western medicine, is applied for wound healing, dermatological disorders, and gastrointestinal illness. We investigated the effects of fermented C. asiatica extract (FCAE), prepared with Lactobacillus, on airway inflammation in a murine model of chronic obstructive pulmonary disease (COPD) induced by cigarette smoke extract (CSE) and lipopolysaccharide (LPS). CSE/LPS stimulation caused marked immune cell infiltration in airways. FCAE (100 and 200 mg/kg) reduced neutrophils in the bronchoalveolar lavage fluid (BALF) by 26.03% and 70.11%, respectively, and decreased activated T cells and B cells in the lung, mediastinal lymph nodes, and Peyer’s patches, while inhibiting collagen fibrosis. FCAE significantly reduced IL-1α (32.51%), CXCL1 (47.63%), CXCL2 (45.37%), and TNF-α (39.51%) levels in the BALF compared with the control group. It also downregulated the expression of muc5ac (58.39%), CXCL1 (67.32%), CXCL2 (57.60%), and TNF-α (54.61%) and suppressed p-STAT3 activation by 50.22%. Furthermore, FCAE enhanced tracheal phenol red secretion by 229.62%, indicating expectorant activity. UPLC analysis identified nine components, which, together with FCAE, inhibited RANTES, TNF-α, and IL-6 in inflammation-induced BEAS-2B cells. Overall, FCAE attenuates immune activation and airway inflammation, supporting its potential as a candidate therapy or functional food for respiratory diseases. Full article

The accurate classification of pancreatic cystic lesions remains clinically challenging due to overlapping imaging features and variable malignant potential. Mucinous cystic neoplasms, in particular, require early identification given their premalignant nature. RNA profiling presents a promising alternative to current diagnostic limitations—a molecular lens sharpened by AI-driven pattern recognition. This study aimed to evaluate the diagnostic potential of RNA signatures for differentiating pancreatic cyst subtypes and to clarify their roles in their pathophysiology. The study included 31 patients with pancreatic lesions who underwent endoscopic ultrasound-guided fine-needle aspiration. RNA was extracted from cyst fluid, tissue, and peripheral blood. Expression of 17 target genes was analyzed using qPCR. Gene expression patterns were compared across mucinous cystic neoplasms, serous cystic neoplasms, pseudocysts, adenocarcinoma, and chronic pancreatitis cohorts. Diagnostic accuracy was evaluated via ROC analysis. Mucinous cysts exhibited significant overexpression of MUC1, ITGA2, ELOVL6, and MUC5AC genes compared to serous cysts and pseudocysts. PKM gene expression correlated with increasing malignant potential. In blood plasma, only MUC1, MUC4, and PYGL were elevated in adenocarcinoma compared to mucinous neoplasms. We identified a distinct RNA signature that can distinguish mucinous cystic neoplasms from benign cystic lesions (serous cysts and pseudocysts), which could be useful for guiding patient management and improving clinical outcomes. Validation in broader cohorts is essential for clinical implementation. Full article

Background/Objectives: Ulcerative colitis (UC) pathogenesis involves gut barrier dysfunction, dysregulated immune responses, and gut microbiota imbalance. Alfalfa polysaccharide (APS), a bioactive compound with immunomodulatory potential, remains underexplored in intestinal inflammation. While APS exhibits anti-inflammatory properties in vitro, its in vivo efficacy, mechanisms, and ability to restore gut microbiota and barrier integrity in UC are unclear. This study aims to investigate the treatment effect of APS on dextran sulfate sodium (DSS)-induced colitis in mice and confirm its prebiotic potential. Methods: A mouse model of ulcerative colitis was induced by DSS. RNA sequencing, Western blotting, the terminal deoxynucleotidyl transferase dUTP nick end labeling technique, and an immuno-histochemical technique were used to study the mechanism of action by which APS at different dosages relieves DSS-induced colitis. Results: The findings show that APS alleviated the symptoms of colitis in mice given DSS, improved the gut morphology, heightened goblet cells production, increased the levels of IL-10 and IL-22, decreased the levels of TNF-α, IL-1β, and IL-6, and prevented the activation of the TLR4/MyD88/NF-κB pathways. Additionally, they maintained the integrity of the intestine by enhancing the expression of the mucins MUC2 and MUC5AC and by increasing the amounts of ZO-1, Occludin, and Claudin-1 proteins. Moreover, APS supported the growth of probiotic bacteria, including unclassified_f_lachnospiraceae, Parabacteroides, Alistipes, and Mucispirillum, and in particular, Parabacteroides distasonis, which is strongly associated with decreased pro-inflammatory cytokine through the inhibition of the TLR4-MyD88-NFκB pathways. Conclusions: APS can be used as a new type of prebiotic to improve UC by regulating intestinal flora and enhancing intestinal barrier function against the TLR4-MyD88-NFκB pathway. Full article