DSS-induced Colitis Research Articles

Preparation and structural characterization of selenium nanoparticles from Lactobacillus reuteri and their protective effects on DSS-induced ulcerative colitis in mice

In this study, selenium nanoparticles (SeNPs) with protection against dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice were prepared extracellularly by co-culturing a sodium selenite solution with Lactobacillus reuteri. Mutiple analytical techniques have shown that SeNPs are mainly composed of C, N, O, and Se elements and are spherical structures encapsulated by polysaccharides or proteins, with a diameter distribution of 70∼130 nm and a potential of approximately -25 mV. The results of cell experiments showed that the prepared SeNPs could significantly reduce the production of nitric oxide (NO) induced by lipopolysaccharide (LPS) in Raw264.7 cells and exert an anti-inflammatory effect by decreasing the levels of TNF-α and IL-1β and increasing the level of IL-10. Animal experiments demonstrated that the SeNPs could effectively alleviate symptoms, such as diarrhea, weight loss, bloody stool, colon shortening, and histopathological changes induced by DSS in mice. They could also reduce mucus damage, goblet cell depletion, and intestinal permeability. In addition, the prepared SeNPs could alleviate colitis by promoting the expression of tight junction proteins, occludin-1 and zonula occluden 1 (ZO-1) and inhibiting oxidative enzymes and pro-inflammatory factors, thereby protecting the barrier function. Analysis of intestinal microbiota revealed that the SeNPs could greatly modulate the gut microbiota in colitis, restore the normal levels of gut microbiota, and enhance immune regulation in mice, thereby inhibiting the further occurrence and development of UC.

The role of Interleukin-38 in modulating T cells in chronic Colitis: A mouse model study

BackgroundInterleukin (IL)-38 belongs to the IL-36 subfamily within the IL-1 family. Patients with inflammatory bowel diseases (IBD) exhibit higher levels of IL-38 in their intestinal tissue compared to healthy controls, suggesting that IL-38 may play a role in the pathogenesis of IBD. However, IL-38′s impact on T cell-mediated immune responses in gastrointestinal inflammation has not been investigated. Therefore, the objective of this work was to elucidate the role of IL-38 in modulating T cells in a mouse model of dextran sulfate sodium (DSS)-induced chronic colitis. MethodsRecombinant IL-38 (rIL-38) was administered intraperitoneally (i.p.) to mice with chronic colitis induced by DSS. Clinical symptoms, length of colon, and histologic alterations were assessed. Cytokine production was quantified using ELISA, and helper T (Th) cell subsets were evaluated via flow cytometry. ResultsAdministration of recombinant IL-38 (rIL-38) alleviated DSS-induced chronic colitis. In addition, animals with chronic colitis treated with rIL-38 exhibited a significant decrease in the spontaneous production of inflammatory cytokines by neutrophils in the lamina propria. Furthermore, rIL-38 treatment increased the absolute numbers and percentages of regulatory T cells (Tregs) but decreased the absolute numbers and percentages of Th1 and Th17 cells. Moreover, rIL-38 treatment also decreased IL-17A-producing γδT cells substantially. ConclusionThis study’s results show that IL-38 reduces the effects of chronic colitis caused by DSS by boosting Treg reactions and reducing Th1/Th17 reactions and IL-17A-producing γδT cells in LPL. Therefore, we propose that IL-38 has the potential to be utilized as a biological therapy agent for IBD.

MyD88 protein destabilization mitigates NF-κB-dependent protection against macrophage apoptosis.

Various signaling pathways are essential for both the innate immune response and the maintenance of cell homeostasis, requiring coordinated interactions among them. In this study, a mutation in the caspase-1 recognition site within MyD88 abolished inflammasome-dependent negative regulation, causing phenotypic changes in mice with some similarities to human NEMO-deficiencies. The MyD88D162E mutation reduced MyD88 protein levels and colon inflammation in DSS-induced colitis mice but did not affect cytokine expression in bone marrow-derived macrophages (BMDMs). However, compared to MyD88wt counterparts, MyD88D162E BMDMs had increased oxidative stress and dysfunctional mitochondria, along with reduced prosurvival Bcl-xL and BTK expression, rendering cells more prone to apoptosis, exacerbated by ibrutinib treatment. NF-κB activation by lipopolysaccharide mitigated this sensitive phenotype. These findings underscore the importance of MyD88wt signaling for NF-κB activation, protecting against macrophage premature apoptosis at resting state. Targeting MyD88 quantity rather than just its signaling could be a promising strategy for MyD88-driven lymphoma treatment.

Protective effect of a newly probiotic Lactobacillus reuteri LY2-2 on DSS-induced colitis.

This study aimed to investigate the role of a newly isolated strain L.reuteri LY2-2 in colitis in mice and explored the underlying mechanisms. METHODS L. LY2-2 was orally administered to mice with dextran sulfate sodium (DSS)-induced colitis. 5-Aminosalicylic acid (5-ASA) treatment was used as the drug control. The results showed that the disease severity of colitis mice was significantly alleviated. The intestinal inflammation was restricted by synergistically reducing pro-inflammatory cytokines, inhibiting TLR4-NF-κB signaling, restoring the abnormal immune response, and enhancing intestinal barrier function. Of note, L.reuteri LY2-2 showed great potential in modulating macrophages polarization in colonic tissues. Moreover, the gut dysbiosis was improved. The potentially pro-inflammatory pathogenic bacteria such as Helicobacter and Romboutsia decreased and the probiotics including L.rhamnosus and L.plantarum increased. Interestingly, the above pathological indexes in the L.reuteri LY2-2 group were better than those in the 5-ASA group. L.reuteri LY2-2 had a better protective effect on DSS-induced colitis via its anti-inflammatory and microbiota-balancing properties, which supports the potential value of this probiotic against colitis. These results contribute to product development of functional probiotics for colitis and provide valuable insights for their mechanisms of biological function to affect human health status.

Isobutyrate exerts a protective effect against liver injury in a DSS-induced colitis by inhibiting inflammation and oxidative stress.

Short-chain fatty acids have been reported to have anti-inflammatory and antioxidant functions; whether isobutyrate, a short-chain fatty acid, is protective against liver injury in a dextran sodium sulfate (DSS)-induced colitis and its molecular mechanism is unknown. In this study, DSS was used to induce a liver injury from a colitis model in piglets, which was expected to prevent and alleviate DSS-induced liver injury by feeding sodium isobutyrate in advance. The results showed that sodium isobutyrate could restore DSS-induced histopathological changes in the liver, inhibit the activation of the toll-like receptor 4/myeloid differentiation primary response 88/nuclear factor kappa-B signaling pathway, and then reduce the DSS-induced release of pro-inflammatory cytokines tumor necrosis factor-α, interleukin 1β, and interleukin 6, reducing inflammatory response. Moreover, we found that sodium isobutyrate could play an antioxidant and apoptosis-reducing role by maintaining reduced mitochondrial function. In conclusion, sodium isobutyrate has a preventive and protective effect on liver injury in a DSS-induced colitis. There is a potential application prospect for it in treating ulcerative-colitis-induced liver injuries. © 2024 Society of Chemical Industry.

Pristimerin Alleviates DSS-Induced Colitis in Mice by Modulating Intestinal Barrier Function, Gut Microbiota Balance and Host Metabolism.

Pristimerin is a pentacyclic triterpenoid mainly derived from Celastraceae plants such as Maytenus ilicifolia, which has been traditionally used for the treatment of gastrointestinal disorders. Pharmacological studies have shown that pristimerin exhibited anti-inflammatory, antioxidant, anticancer and antibacterial activities. However, the potential mechanism of pristimerin for the treatment of ulcerative colitis (UC) remains elusive. In the present study, pristimerin could effectively inhibit the NO generation induced by LPS in RAW 264.7 cells and upregulate the decreased expression of tight junction proteins such as occludin and claudin-1. In vivo, oral administration of pristimerin (0.5 mg/kg and 1 mg/kg) could significantly relieve UC symptoms such as body weight loss, disease activity index, shortened colon length and colonic pathological damage. Meanwhile, pristimerin decreased the TNF-α, MPO and MDA levels and increased the levels of IL-10, IL-22, SOD activity, occludin and claudin-1 in colon tissues. Gut microbiota analysis of cecum contents revealed that pristimerin treatment effectively alleviated gut microbiota dysbiosis. Additionally, serum metabolomics showed that 33 potential biomarkers involving lipid and tryptophan metabolism were identified, which may account for the therapeutic effects of pristimerin on UC mice. In conclusion, our findings indicate that pristimerin attenuates UC symptoms in DSS-induced mice through modulating intestinal barrier integrity, gut microbiota composition, lipid and tryptophan metabolism.

Decursin protects against DSS-induced experimental colitis in mice by inhibiting the cGAS-STING signaling pathway.

While studies have shown that Angelica gigas Nakai (A. gigas) can alleviate ulcerative colitis in mice, the therapeutic role of its main active ingredient, decursin, is uncertain. Therefore, we aimed to investigate the protective effect and mechanism of decursin against inflammatory bowel disease (IBD) in vivo using mice. IBD was simulated via induction with 3% dextran sodium sulfate (DSS), with or without daily treatment with decursin (10 mg/kg or 20 mg/kg) or 5-amino salicylic acid (5-ASA; 100 mg/kg) for 14 days. Mice were weighed and monitored daily for disease activity index (DAI) scoring. Colon tissues were collected for histopathological staining analysis, and serum was collected for ELISA measurement of proinflammatory cytokines. Western blotting was employed to analyze colonic expression levels of the tight junction-related proteins ZO-1, Occludin, and Claudin 1, as well as cGAS-STING signaling pathway-associated proteins. The expression levels of major proteins were verified using immunohistochemistry and immunofluorescence. Compared with the control group, DSS-induced mice showed decreased body weight, increased DAI scores, shortening of the colon, disrupted colon tissue structure, increased serum levels of proinflammatory cytokines, increased expression of factors involved in activating the cGAS-STING signaling pathway, and reduced expression of ZO-1, Occludin, and Claudin 1. Under decursin treatment, the pathological state of IBD was less severe, proinflammatory factors were downregulated, and activation of the cGAS-STING signaling pathway was inhibited. Our findings indicate that decursin helps restore the intestinal mucosal barrier and prevents activation of the cGAS-STING signaling cascade, alleviating experimental IBD in mice.

Harnessing a Safe Novel Lipid Nanoparticle: Targeted Oral Delivery to Colonic Epithelial and Macrophage Cells in a Colitis Mouse Model

A novel lipid nanoparticle (nLNP), formulated with three essential lipids to mimic ginger-derived exosomal particles, shows strong potential for delivering IL-22 mRNA specifically to the colon, presenting a unique oral drug delivery system for inflammatory bowel disease (IBD). However, its cellular targets and uptake behavior in healthy versus diseased colons remain unclear. Understanding these aspects is crucial for fully elucidating its targeting effectiveness in inflamed colon tissue. This study investigates the nLNP’s cellular targets in healthy and diseased mouse colons. Flow cytometry compared nLNP uptake in healthy mice and a DSS-induced acute colitis model. The results revealed efficient internalization of nLNP by colonic epithelial cells in healthy and inflamed mice. In non-inflamed mice, the small number of colonic macrophages resulted in minimal uptake of nLNP by these cells. In inflamed mice, macrophages migrated to the damaged epithelium, where nLNP uptake was significantly increased, highlighting the nLNP’s ability to target both epithelial and macrophage cells during inflammation. Additionally, safety assessments showed that the nLNP neither altered in vitro kinase activities nor exhibited immunotoxicity or induced in vivo toxicity at the maximum tolerated oral dose. These findings underscore the nLNP’s safety and potential as a promising epithelial/macrophage-targeted drug delivery platform for oral ulcerative colitis (UC) treatment.

Exploring the mechanism of Suxin Hugan Fang in treating ulcerative colitis based on network pharmacology

As a traditional Chinese medicine formula used in clinical practice for an extended period, Suxin-Hugan-Fang (SXHGF) exhibits excellent anti-inflammatory properties. However, the efficacy of SXHGF in treating ulcerative colitis (UC) and its mechanism of action are still unclear. In this study, the therapeutic effects of SXHGF on UC were evaluated using network pharmacology and experimental validation, while also investigating its mechanism of action. By administering DSS to C57BL/6 mice to construct a mouse model of ulcerative colitis, the therapeutic effect of SXHGF on ulcerative colitis was evaluated based on weight loss percentage, disease activity index, colon length changes, and pathological conditions as indicators. The main chemical components of SXHGF were determined by LC-MS-QTOF method. The potential targets and mechanisms of action of SXHGF in the treatment of UC were inferred using bioinformatics methods, and further validated through ELISA, IHC, and Western blotting assays. The experimental results demonstrate that SXHGF can suppress oxidative stress and oxidative damage in the colon tissue of UC mice, and alleviate DSS-induced ulcerative colitis by inhibiting the JAK2/STAT3 and NFκB pathways.

Discovery of Thiazole Carboxamides as Novel Vanin-1 Inhibitors for Inflammatory Bowel Disease Treatment.

Inflammatory bowel disease (IBD) is a clinically heterogeneous disease demanding more therapeutic targets and intervention strategies. Vanin-1, an oxidative stress-regulating protein, has emerged as a promising target for alleviating inflammation and oxidative stress. In this study, a series of thiazole carboxamide derivatives as vanin-1 inhibitors were designed and synthesized. The preferred compound, X17, demonstrated potent inhibition against vanin-1 at the protein, HT-29 cell, and tissue levels, whose binding mode with the target was confirmed via the cocrystal structure. X17 achieved a high bioavailability of 81% in rats, accompanied by concentration-dependent inhibition of serum vanin-1. In a DSS-induced mouse colitis model, X17 exhibited potent anti-inflammatory and antioxidant activities, repressing the inflammatory factor expressions and myeloperoxidase activity, elevating the colonic glutathione reserve, and restoring the intestinal barrier. Collectively, these findings depict the discovery of a potent vanin-1 inhibitor, providing an opportunity for further drug candidate development for treating IBD.

Effect of Bacillus clausii in attenuating symptoms of DSS-induced ulcerative colitis by modulating NFkB pathway and oxidative stress in mice.

Ulcerative colitis (UC) is a condition characterized by inflammation and ulcer formation in the colon and rectum due to genetic and environmental factors. It is a common condition, with a global prevalence rate exceeding 0.3%. Current treatments have limited efficacy and can cause unwanted side effects, leading to a high recurrence rate and reduced quality of life for patients. This study suggests that Bacillus clausii has a beneficial role in reducing intestinal inflammation and relieving colitis symptoms in mice. The study aimed to examine B. clausii's potential to reduce the progression and pathogenesis of dextran sulphate sodium (DSS)-induced UC. Bacillus clausii was administered to mice as a pre-treatment, post-treatment and adjunct treatment with sulfasalazine for 14 days. The study found that B. clausii effectively reduced the severity of colitis in mice when used preventatively. Administering B. clausii after the onset of colitis also effectively alleviated symptoms. Combining B. clausii with standard sulfasalazine as adjunct therapy was more effective in reducing intestinal inflammation than using a single therapy alone. B. clausii has shown the potential to prevent colon damage and decrease the likelihood and severity of the disease. Immunohistochemistry results revealed a decrease in the expression of pro-inflammatory cytokines such as IL-1β, TNF-α and NFkB in colon tissue. Additionally, mice that received B. clausii showed a significant increase in anti-oxidant levels and improved haematological markers. In conclusion, it must be emphasized that B. clausii possesses the potential to alleviate the symptoms of UC.

A Novel Synbiotic Protects Against DSS-Induced Colitis in Mice via Anti-inflammatory and Microbiota-Balancing Properties.

Inflammatory bowel disease (IBD) is a chronic immune-inflammatory disease. Gut microbes, intestinal immunity, and gut barrier function play a critical role in IBD. Growing evidence suggests that synbiotic may offer therapeutic benefits for individuals with colitis, suggesting an alternative therapy against colitis. With this in mind, we creatively prepared a new synbiotic combination consisting of a probiotic strain (Limosilactobacillus reuteri) along with one prebiotic chitooligosaccharides (COS). The protective effects of the synbiotic on DSS-induced colitis and the underlying mechanisms were investigated. We demonstrated that the synbiotic ameliorated colitis in mice, as evidenced by a significant remission in body weight loss and colon shortening, and a decreased disease activity index (DAI). Notably, synbiotic reduced the intestinal inflammation and injury by synergistically decreasing inflammatory factors, inhibiting TLR4/Myd88/NF-κB/NLRP3 signaling, preventing macrophage infiltration, and enhancing the integrity of the intestinal barrier. Moreover, synbiotic selectively promoted the growth of beneficial bacteria (e.g., Akkermansia, Lactobacillus) but decreased the pathogenic bacteria (e.g., Helicobacter). BugBase's analysis supported its ameliorated role in reducing pathogenic bacteria. Collectively, our findings revealed the novel synbiotic had a potential to treat colitis, which was associated with its anti-inflammatory and microbiota-balancing properties. This study will contribute to the development of functional synbiotic products for IBD therapy and will provide valuable insights into their mechanisms.

Metabolomic insights into the beneficial effects of dietary purple potato on DSS-induced murine colon colitis

Inflammatory bowel disease (IBD) is characterized by disturbance in intestinal flora and metabolomic profiles. Building on previous findings that purple potato (PP) supplementation suppresses inflammation and restores intestinal barrier in dextran sulfate sodium (DSS)-treated mice, this study examined changes in the fecal metabolome in the same cohort. Mice were fed 0 % or 10 % PP for 7 weeks, with DSS administered in the fifth week of dietary treatment followed by one-week normal drinking water recovery. A total of 68 metabolites, including amino acids, fatty acids, organic acids, carbohydrates, and polyamines, were significantly altered across the groups. PP supplementation reversed changes in 13 of the 25 DSS-altered metabolites. Six microbial metabolites derived from PP polyphenols were identified and positively correlated with M2 macrophage polarization. Data suggest that dietary PP is effective in reducing inflammation and improves gut metabolites in DSS-induced colitis mice, offering a potential dietary therapy for managing IBD.

Diallyl trisulfide alleviates dextran sulphate sodium-induced colitis in mice by inhibiting NLRP3 inflammasome activation via ROS/Trx-1 pathway.

Diallyl trisulfide (DATS), a sulphur-containing compound isolated from the medicinal food plant garlic, has been previously reported to attenuate experimental colitis induced by either dextran sodium sulphate (DSS) or 2,4,6-trinitrobenzenesulfonic acid (TNBS) in mice; however, the underlying mechanism remains to be identified. In this study, we deciphered the key mechanism by which DATS alleviates ulcerative colitis (UC). We showed that oral administration of DATS for 10 consecutive days greatly restrained the infiltration of macrophages and the pathological changes in colonic tissues of mice with DSS-induced colitis. DATS treatment notably dampened the content of IL-1β and IL-18 and suppressed NLRP3 inflammasome activation in colon. Mechanistically, DATS effectively diminished the generation of ROS in macrophages. The suppressive effect of DATS on the activation of NLRP3 inflammasome and downregulation of IL-18 and IL-1β levels was blunted by xanthine oxidase. Further studies revealed that DATS inhibited NF-κB pathway activation by suppressing the expression of Trx-1, thereby inhibiting NLRP3 inflammasome activation. Trx-1 overexpression and interference in macrophages promoted and diminished NLRP3 inflammasome activation, respectively. In summary, garlic and its main active ingredient DATS have potentials to prevent and treat UC, and DATS functions by inhibiting NLRP3 inflammasome activation via Trx-1/ROS pathway.

Metabolomics reveals the potential metabolic mechanism of infliximab against DSS-induced acute and chronic ulcerative colitis.

Inflammatory bowel disease (IBD) is often accompanied by metabolic imbalance, and infliximab (IFX) can alleviate IBD symptoms, but its metabolic mechanisms remain unclear. To investigate the relationship between IBD, metabolism, and IFX, an acute and chronic ulcerative colitis (UC) model induced by dextran sulfate sodium (DSS) was established. Plasma samples were analyzed using ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry, followed by multivariate statistical analysis. The results showed that IFX could alleviate colonic shortening and reduce colonic pathological damage in acute and chronic mouse colitis, improve acute and chronic UC, and ameliorate metabolic disturbances. Among the 104 elevated metabolites and 170 decreased metabolites, these metabolites mainly belonged to amino acids, glucose, and purines. The changes in these metabolites were mainly associated with drug metabolism-other enzymes, riboflavin metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, phosphonate and phosphinate metabolism, and phenylalanine metabolism. In summary, this study provides a valuable approach to explore the metabolic mechanisms of IFX in treating acute and chronic UC from a metabolomics perspective.

Unveiling the therapeutic potential and mechanism of inulin in DSS-induced colitis mice

Inulin has been reported to alleviate colitis. In this study, colitis patients' feces were used to simulate fermentation to demonstrate changes in the microbiota profile in the presence of inulin. We found inulin can reshape the gut microbiota profile of colitis patients, especially by altering the abundance of Faecalibacterium and Blautia. Interestingly, the subsequent co-culture with inulin demonstrated that inulin promoted the growth of these two strains of bacteria. The dextran sodium sulfate (DSS)-induced mouse model was used to examine the effect of inulin and its combination with two probiotics on colitis. Results showed that all three treatments can alleviate the clinical symptoms, including weight-losing, colon-shortening, and the Disease Activity Index (DAI) score. Further investigations showed that the administrations regulate colitis mice's pro- and anti-inflammatory cytokines, such as TNF-α, IL-1β, IL-6, IL-10, and IL-17. Also, they alter the relative abundance of Faecalibacterium and Blautia, change the short-chain fatty acids (SCFAs) profile in the cecum and colon, and improve the intestinal barrier; specifically, the intervention increased the expressions of Claudin, Occludin, Zonula Occludens (ZO)-1, and Mucin (MUC)-2 in colonic tissues, thus restoring the colonic tissue structure and morphology of colitis mice. Collectively, our results confirm that inulin can alter the colitis patients' characteristic microbial community, and they can ameliorate experimental colitis by inhibiting the TRL4/MyD88/NF-κB signaling pathway—improving the inflammatory response and enhancing the intestinal barrier. In conclusion, we propose that inulin may hold promise as a functional food therapeutic approach for the treatment of colitis.

Vitamin K2 alleviates dextran sulfate sodium-induced colitis via inflammatory responses, gut barrier integrity, and the gut microbiota in mice

Vitamin K2 (VK2) has been shown to have potential benefits in improving intestinal integrity, but its potential and mechanisms for alleviating intestinal inflammation are still unclear. The present results showed that VK2 supplementation significantly alleviated the symptoms of colitis and maintained the intestinal barrier integrity. In addition, VK2 significantly down-regulated the mRNA expression levels of pro-inflammatory cytokines including IL-1β, IL-6, and TNF-α, while up-regulated the mRNA expression level of anti-inflammatory cytokines such as IL-10. Moreover, VK2 significantly alleviated DSS-induced intestinal epithelial barrier dysfunction by maintaining the tight junction function. Furthermore, VK2 also regulated DSS-induced gut microbiota dysbiosis by reshaping the structure of gut microbiota, such as increasing the relative abundance of Firmicutes, Euryarchaeota, Prevotellaceae, and Prevotella and reducing the relative abundance of Proteobacteria, Rikenellaceae, Enterobacteriaceae, Acetatifactor, and Alistioes. In conclusion, these results indicated that VK2 effectively alleviates DSS-induced colitis in mice by modulating the gut microbiota.

Glycyrrhizic acid and patchouli alcohol in Huoxiang Zhengqi attenuate intestinal inflammation and barrier injury via regulating endogenous corticosterone metabolism mediated by 11β-HSD1

Ethnopharmacological relevanceUlcerative colitis (UC), a chronic inflammatory bowel disease, has become a significant public health challenge due to the limited effectiveness of available therapies. Huoxiang Zhengqi (HXZQ), a well-established traditional Chinese formula, shows potential in managing UC, as suggested by clinical and pharmacological studies. However, the active components and mechanisms responsible for its effects remain unclear. Aim of studyThis study aimed to identify the bioactive components of HXZQ responsible for its therapeutic effects on UC and to elucidate their underlying mechanisms. Materials and methodsThe effect of HXZQ against dextran sodium sulfate (DSS) -induced colitis was investigated. Ingredients in HXZQ were characterized and analyzed in colitic mice using liquid chromatography–mass spectrometry (LC-MS) and gas chromatography–mass spectrometry (GC-MS). In vitro, biological activity of compounds was assessed using lipopolysaccharide (LPS)-induced Ana-1 cells and bone marrow-derived macrophages (BMDMs), tumor necrosis factor-alpha-induced Caco-2 cells, and isolated intestinal crypts from colitic mice. These results were confirmed in vivo. The targets of the components were identified through bioinformatics analysis and validated via molecular docking, enzyme inhibition assays, and in vivo experiments. Hematoxylin and eosin (HE) staining, periodic acid-Schiff (PAS) staining, immunohistochemistry, enzyme-linked immunosorbent assay (ELISA), western blotting, and quantitative real-time polymerase chain reaction (qPCR) were employed to confirm the pharmaceutical effects. ResultsA clinical equivalent dose of HXZQ (2.5 mL/kg) effectively treated DSS-induced colitis. 113 compounds were identified in HXZQ, with 35 compounds detected in colitic mice. Glycyrrhizic acid (GA) and patchouli alcohol (PA) emerged as key contributors to the anti-colitic effects of HXZQ. Further investigation revealed that HXZQ and its active components decreased the levels of pro-inflammatory cytokines TNF-α, interleukin-1β (IL-1β), and interleukin-6 (IL-6) in colon, likely by inhibiting nuclear factor kappa-B (NF-κB) signaling pathway. This inhibition indirectly activated the intestinal farnesoid X receptor (FXR) signaling pathway, correcting bile acid imbalances caused by colitis. Additionally, these components significantly enhanced the expression of tight junction proteins ZO-1 and Occludin, as well as the adhesion protein E-cadherin, and reduced goblet cell loss, thereby repairing intestinal barrier injury. Mechanistically, GA and PA were found to inhibit 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) activity, leading to increased local active corticosterone levels in the intestine to exert anti-inflammatory effects. Notably, the inhibition of 11β-HSD1 with the selective inhibitor BVT ameliorated colitis in mice. ConclusionsHXZQ exhibits therapeutic effects on UC, primarily through GA and PA inhibiting 11β-HSD1. This suggests new natural therapy approaches for UC and positions 11β-HSD1 as a potential target for colitis treatment.

Induction of multicomponent peptide assembly via solvent exchange strategy for enhanced structure and bioactivities

Multicomponent peptides, composed of numerous peptides with various binding sites and functionalities, are increasingly exploited in nanotechnology, biomedicine and functional food applications. This article reported that nucleation and growth of Zein (Z) during solvent exchange could form a confined space to drive spontaneous self-assembly of multicomponent peptides. The self-assembly process began with a concentration gradient generated by the exchange of water and ethanol driving the nucleation of Z to form small aggregates, while multicomponent peptides selectively or anisotropically adsorbed on the Z surface via electrostatic interactions and hydrophobic interactions, participating in and controlling the assembly kinetics, ultimately leading to the formation of well-defined nanoparticles (NPs). The multicomponent peptides-based assemblies could effectively encapsulate the hydrophobic functional agent quercetin (Que), presenting good biocompatibility, antioxidant activity, and preventing DSS-induced colitis. This study elucidated the self-assembly mechanism of multicomponent peptides and demonstrated their synergistic effects with hydrophobic compounds for disease prevention, offering valuable insights into the development of novel functional materials to regulate human health.

Folic Acid - Based Hydrogels Co-assembled with Protocatechuic Acid for Enhanced Treatment of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) presents a significant therapeutic challenge due to the need for oral drug delivery systems that withstand acidic environment of stomach while effectively targeting intestinal inflammation. To address this issue, we created a novel hydrogel system based on a folic acid (FA)-dopamine (DA) conjugate, co-assembled with protocatechuic acid (PCA), to form F-DP hydrogels. These hydrogels demonstrated robust anti-gastric acid, mucosal adhesive, and injectable properties, enhancing their efficacy for targeted delivery. In DSS-induced colitis mouse models, treatment with F-DP hydrogels resulted in significant therapeutic improvements, including increased body weight, reduced disease activity index (DAI), and maintained colon length. Biochemical assays revealed that F-DP hydrogels significantly enhanced antioxidant enzyme activities (GSH and SOD) and reduced oxidative stress markers (NO and MDA). Histological assessments confirmed effective repair of the colonic mucosal barrier, restoration of tight junction protein ZO-1, and reduction of inflammatory lesions. Furthermore, immunofluorescence staining indicated that F-DP hydrogels facilitated macrophages polarization from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype, thereby reducing inflammation and promoting tissue repair. Our study demonstrates that F-DP hydrogels show significant potential for improving IBD treatment through enhanced gastric resistance, intestinal adhesion, and synergistic anti-inflammatory effects, warranting further investigation for clinical applications.