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1.
J Agric Food Chem ; 72(19): 10923-10935, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38691832

RESUMO

This study aimed to explore the ameliorative effects and potential mechanisms of Huangshan Umbilicaria esculenta polysaccharide (UEP) in dextran sulfate sodium-induced acute ulcerative colitis (UC) and UC secondary liver injury (SLI). Results showed that UEP could ameliorate both colon and liver pathologic injuries, upregulate mouse intestinal tight junction proteins (TJs) and MUC2 expression, and reduce LPS exposure, thereby attenuating the effects of the gut-liver axis. Importantly, UEP significantly downregulated the secretion levels of TNF-α, IL-1ß, and IL-6 through inhibition of the NF-κB pathway and activated the Nrf2 signaling pathway to increase the expression levels of SOD and GSH-Px. In vitro, UEP inhibited the LPS-induced phosphorylation of NF-κB P65 and promoted nuclear translocation of Nrf2 in RAW264.7 cells. These results revealed that UEP ameliorated UC and SLI through NF-κB and Nrf2-mediated inflammation and oxidative stress. The study first investigated the anticolitis effect of UEP, suggesting its potential for the treatment of colitis and colitis-associated liver disease.


Assuntos
Colite , Sulfato de Dextrana , Fator 2 Relacionado a NF-E2 , NF-kappa B , Polissacarídeos , Animais , Camundongos , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/administração & dosagem , Sulfato de Dextrana/efeitos adversos , Masculino , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Humanos , Colite/tratamento farmacológico , Colite/induzido quimicamente , Colite/metabolismo , Células RAW 264.7 , NF-kappa B/metabolismo , NF-kappa B/genética , Camundongos Endogâmicos C57BL , Substâncias Protetoras/farmacologia , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/imunologia , Estresse Oxidativo/efeitos dos fármacos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-1beta/imunologia , Interleucina-6/genética , Interleucina-6/metabolismo , Interleucina-6/imunologia , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Colite Ulcerativa/induzido quimicamente , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Mucina-2/genética , Mucina-2/metabolismo
2.
Int J Biol Macromol ; 267(Pt 2): 131434, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38614182

RESUMO

The gastrointestinal (GI) tract's mucus layer serves as a critical barrier and a mediator in drug nanoparticle delivery. The mucus layer's diverse molecular structures and spatial complexity complicates the mechanistic study of the diffusion dynamics of particulate materials. In response, we developed a bi-component coarse-grained mucus model, specifically tailored for the colorectal cancer environment, that contained the two most abundant glycoproteins in GI mucus: Muc2 and Muc5AC. This model demonstrated the effects of molecular composition and concentration on mucus pore size, a key determinant in the permeability of nanoparticles. Using this computational model, we investigated the diffusion rate of polyethylene glycol (PEG) coated nanoparticles, a widely used muco-penetrating nanoparticle. We validated our model with experimentally characterized mucus pore sizes and the diffusional coefficients of PEG-coated nanoparticles in the mucus collected from cultured human colorectal goblet cells. Machine learning fingerprints were then employed to provide a mechanistic understanding of nanoparticle diffusional behavior. We found that larger nanoparticles tended to be trapped in mucus over longer durations but exhibited more ballistic diffusion over shorter time spans. Through these discoveries, our model provides a promising platform to study pharmacokinetics in the GI mucus layer.


Assuntos
Muco , Nanopartículas , Polietilenoglicóis , Humanos , Nanopartículas/química , Difusão , Polietilenoglicóis/química , Muco/metabolismo , Muco/química , Mucina-2/metabolismo , Mucina-2/química , Mucina-5AC/metabolismo , Mucina-5AC/química , Mucosa Intestinal/metabolismo , Trato Gastrointestinal/metabolismo , Células Caliciformes/metabolismo , Modelos Biológicos
3.
Nutrients ; 16(8)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38674791

RESUMO

Sleep deprivation (SD) leads to impaired intestinal barrier function and intestinal flora disorder, especially a reduction in the abundance of the next generation of probiotic Faecalibacterium prausnitzii (F. prausnitzii). However, it remains largely unclear whether F. prausnitzii can ameliorate SD-induced intestinal barrier damage. A 72 h SD mouse model was used in this research, with or without the addition of F. prausnitzii. The findings indicated that pre-colonization with F. prausnitzii could protect against tissue damage from SD, enhance goblet cell count and MUC2 levels in the colon, boost tight-junction protein expression, decrease macrophage infiltration, suppress pro-inflammatory cytokine expression, and reduce apoptosis. We found that the presence of F. prausnitzii helped to balance the gut microbiota in SD mice by reducing harmful bacteria like Klebsiella and Staphylococcus, while increasing beneficial bacteria such as Akkermansia. Ion chromatography analysis revealed that F. prausnitzii pretreatment increased the fecal butyrate level in SD mice. Overall, these results suggested that incorporating F. prausnitzii could help reduce gut damage caused by SD, potentially by enhancing the intestinal barrier and balancing gut microflora. This provides a foundation for utilizing probiotics to protect against intestinal illnesses.


Assuntos
Disbiose , Faecalibacterium prausnitzii , Microbioma Gastrointestinal , Mucosa Intestinal , Probióticos , Privação do Sono , Animais , Privação do Sono/complicações , Camundongos , Probióticos/farmacologia , Probióticos/administração & dosagem , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Masculino , Fezes/microbiologia , Camundongos Endogâmicos C57BL , Suplementos Nutricionais , Modelos Animais de Doenças , Mucina-2/metabolismo , Butiratos/metabolismo , Colo/microbiologia , Colo/metabolismo
4.
Nutrients ; 16(8)2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38674854

RESUMO

Enterohemorrhagic Escherichia coli (EHEC) serotype O157:H7 is a commonly encountered foodborne pathogen that can cause hemorrhagic enteritis and lead to hemolytic uremic syndrome (HUS) in severe cases. Bifidobacterium is a beneficial bacterium that naturally exists in the human gut and plays a vital role in maintaining a healthy balance in the gut microbiota. This study investigated the protective effects of B. longum K5 in a mouse model of EHEC O157:H7 infection. The results indicated that pretreatment with B. longum K5 mitigated the clinical symptoms of EHEC O157:H7 infection and attenuated the increase in myeloperoxidase (MPO) activity in the colon of the mice. In comparison to the model group, elevated serum D-lactic acid concentrations and diamine oxidase (DAO) levels were prevented in the K5-EHEC group of mice. The reduced mRNA expression of tight junction proteins (ZO-1, Occludin, and Claudin-1) and mucin MUC2, as well as the elevated expression of virulence factors Stx1A and Stx2A, was alleviated in the colon of both the K5-PBS and K5-EHEC groups. Additionally, the increase in the inflammatory cytokine levels of TNF-α and IL-1ß was inhibited and the production of IL-4 and IL-10 was promoted in the K5-EHEC group compared with the model group. B. longum K5 significantly prevented the reduction in the abundance and diversity of mouse gut microorganisms induced by EHEC O157:H7 infection, including blocking the decrease in the relative abundance of Roseburia, Lactobacillus, and Oscillibacter. Meanwhile, the intervention with B. longum K5 promoted the production of acetic acid and butyric acid in the gut. This study provides insights into the use of B. longum K5 for developing probiotic formulations to prevent intestinal diseases caused by pathogenic bacterial infections.


Assuntos
Bifidobacterium longum , Colo , Infecções por Escherichia coli , Escherichia coli O157 , Microbioma Gastrointestinal , Probióticos , Animais , Camundongos , Probióticos/farmacologia , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/microbiologia , Colo/microbiologia , Colo/metabolismo , Modelos Animais de Doenças , Mucina-2/metabolismo , Citocinas/metabolismo , Peroxidase/metabolismo , Amina Oxidase (contendo Cobre)/metabolismo
5.
Food Funct ; 15(9): 5118-5131, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38682277

RESUMO

This study investigated the impact of in vivo available colon-mango (poly)phenols on stress-induced impairment of intestinal barrier function. Caco-2/HT29-MTX cells were incubated with six extracts of ileal fluid collected pre- and 4-8 h post-mango consumption before being subjected to inflammatory stress. (Poly)phenols in ileal fluids were analysed by UHPLC-HR-MS. Epithelial barrier function was monitored by measurement of trans-epithelial electrical resistance (TEER) and the production of selected inflammatory markers (interleukin-8 (IL-8) and nitric oxide (NO)) and the major mucin of the mucosal layer (MUC2). Post-mango intake ileal fluids contained principally benzoic acids, hydroxybenzenes and galloyl derivatives. There was a high interindividual variability in the levels of these compounds, which was reflected by the degree of variability in the protective effects of individual ileal extracts on inflammatory changes in the treated cell cultures. The 24 h treatment with non-cytotoxic doses of extracts of 4-8 h post-mango intake ileal fluid significantly reduced the TEER decrease in monolayers treated with the inflammatory cytomix. This effect was not associated with changes in IL-8 expression and secretion or claudine-7 expression. The mango derived-ileal fluid extract (IFE) also mitigated cytomix-dependent nitrite secretion, as a proxy of NO production, and the MUC2 reduction observed upon the inflammatory challenge. These insights shed light on the potential protective effect of mango (poly)phenols on the intestinal barrier exposed to inflammatory conditions.


Assuntos
Interleucina-8 , Mucosa Intestinal , Mangifera , Mucina-2 , Humanos , Mangifera/química , Células CACO-2 , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Interleucina-8/metabolismo , Mucina-2/metabolismo , Células HT29 , Polifenóis/farmacologia , Colo/efeitos dos fármacos , Colo/metabolismo , Óxido Nítrico/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Inflamação/tratamento farmacológico , Função da Barreira Intestinal
6.
Sci Rep ; 14(1): 6954, 2024 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521809

RESUMO

Mucin protein glycosylation is important in determining biological properties of mucus gels, which form protective barriers at mucosal surfaces of the body such as the intestine. Ecological factors including: age, sex, and diet can change mucus barrier properties by modulating mucin glycosylation. However, as our understanding stems from controlled laboratory studies in house mice, the combined influence of ecological factors on mucin glycosylation in real-world contexts remains limited. In this study, we used histological staining with 'Alcian Blue, Periodic Acid, Schiff's' and 'High-Iron diamine' to assess the acidic nature of mucins stored within goblet cells of the intestine, in a wild mouse population (Mus musculus). Using statistical models, we identified sex as among the most influential ecological factors determining the acidity of intestinal mucin glycans in wild mice. Our data from wild mice and experiments using laboratory mice suggest estrogen signalling associates with an increase in the relative abundance of sialylated mucins. Thus, estrogen signalling may underpin sex differences observed in the colonic mucus of wild and laboratory mice. These findings highlight the significant influence of ecological parameters on mucosal barrier sites and the complementary role of wild populations in augmenting standard laboratory studies in the advancement of mucus biology.


Assuntos
Colo , Mucinas , Camundongos , Feminino , Masculino , Animais , Mucinas/metabolismo , Colo/patologia , Células Caliciformes/metabolismo , Intestinos , Estrogênios/metabolismo , Mucina-2/metabolismo , Mucosa Intestinal/metabolismo
7.
Cell Biochem Funct ; 42(2): e3989, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38500386

RESUMO

Colorectal mucinous adenocarcinoma (MAC) is one of the most lethal histological types of colorectal cancer, and its mechanism of development is not well understood. In this study, we aimed to clarify the molecular characteristics of MAC via in silico analysis using The Cancer Genome Atlas database. The expression of genes on chromosome 20q (Chr20q) was negatively associated with the expression of MUC2, which is a key molecule that can be used to distinguish between MAC and nonmucinous adenocarcinoma (NMAC). This was consistent with a significant difference in copy number alteration of Chr20q between the two histological types. We further identified 475 differentially expressed genes (DEGs) between MAC and NMAC, and some of the Chr20q genes among the DEGs are considered to be pivotal genes used to define MAC. Both in vitro and in vivo analysis showed that simultaneous knockdown of POFUT1 and PLAGL2, both of which are located on Chr20q, promoted MUC2 expression. Moreover, these genes were highly expressed in NMAC but not in MAC according to the results of immunohistological studies using human samples. In conclusion, POFUT1 and PLAGL2 are considered to be important for defining MAC, and these genes are associated with MUC2 expression.


Assuntos
Adenocarcinoma Mucinoso , Adenocarcinoma , Neoplasias Colorretais , Humanos , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/metabolismo , Adenocarcinoma Mucinoso/patologia , Neoplasias Colorretais/metabolismo , Proteínas de Ligação a DNA/metabolismo , Mucina-2/genética , Mucina-2/metabolismo , Proteínas de Ligação a RNA/genética , Fatores de Transcrição/genética
8.
Res Vet Sci ; 171: 105226, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38502998

RESUMO

This study aimed to investigate the effects of early or late feeding strategies and prebiotic, on immune responses and gut health during the early life stage of broiler chickens. A total of 240 day-old male broiler chicks were used in a 2 × 3 factorial arrangement of treatments that comprised 2 feeding strategies (early or late) and 3 levels of prebiotic (0, recommended dosage or three times the recommended dosage) in a completely randomized design with 4 pen replicates and 10 broilers per each. Compared to broiler chickens that had early access to feed, delayed access to feed resulted in an increased population of Escherichia coli and a decreased population of Lactobacillus spp. and Bifidobacterium spp. in the ileum (P < 0.05). Additionally, delayed access to feed led to a decrease in villus height, crypt depth, villus height: villus width ratio, goblet cell density, and mucin 2 gene expression in the ileum (P < 0.05). The supplementation of prebiotics in both the late and early feeding strategy groups resulted in increased villus height, crypt depth, goblet cell density, mucin 2 gene expression, and antibodies against Infectious Bursal Disease (IBD). Additionally, it led to an improvement in the foot web thickness index (P < 0.05). Furthermore, it resulted in a significant decrease in the population of Escherichia coli, while the populations of Lactobacillus spp. and Bifidobacterium spp. in the ileum were significantly increased (P < 0.05). Therefore, this study suggests that incorporating prebiotics in the starter diet can effectively enhance immune responses and promote gut health, regardless of the feeding strategy (early or late). In conclusion, this study demonstrates the potential benefits of incorporating prebiotics into poultry diets to alleviate the detrimental effects of delayed access to feed and improve gut health during the early life stage of broiler chickens.


Assuntos
Galinhas , Prebióticos , Animais , Masculino , Galinhas/microbiologia , Mucina-2 , Dieta/veterinária , Imunidade , Escherichia coli , Ração Animal/análise , Suplementos Nutricionais , Fenômenos Fisiológicos da Nutrição Animal
9.
Appl Immunohistochem Mol Morphol ; 32(4): 183-188, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38478391

RESUMO

Glandular odontogenic cysts (GOCs) and dentigerous cysts may show mucous metaplasia. Central mucoepidermoid carcinoma is very rare and mostly associated with dental cysts. It is hypothesized that odontogenic cysts showing mucus differentiation in their lining, have a propensity to transform into MEC. The present study is the first attempt to explore the relationship between odontogenic cysts [GOCs and dentigerous cysts with mucus metaplasia (DCMM)] and MEC by evaluating immunoexpression of MUC5AC and MUC2. Immunoexpression of MUC5AC and MUC2 was evaluated semiquantitatively in GOCs (20 cases), DCMMs (20 cases), and MECs (20 cases). The percentage of positive cells, intensity, and localization of immunoexpression were assessed for each marker in all cases. Of GOCs, DCMMs, and MECs cases, 85%, 70%, and 80%, respectively, were immunopositive for MUC5AC. Strong cytoplasmic immunoreactivity for MUC5AC was noted, particularly in mucous cells present diffusely within MECs. However, the immunoreactivity was limited to the epithelial lining of GOCs and DCMMs. Most of the MECs (60%) showed more than 25% positivity for MUC5AC, followed by GOCs, and the least in DMMCs. Mild cytoplasmic and nuclear positivity of MUC2 was noted only in epithelial lining cells of 70% GOCs and 45% DCMMs. Whereas, 55% of MECs displayed moderate to strong cytoplasmic and membranous immunopositivity for MUC2 exclusively within mucous cells. As MECs showed strong MUC5AC immunoreactivity in mucous cells, immunoexpression of MUC5AC in odontogenic cysts with mucus cells can possibly explain the pathogenesis of MEC from cysts. However, the variable expression of MUC2 did not give any strong evidence regarding its role as a marker.


Assuntos
Carcinoma Mucoepidermoide , Cisto Dentígero , Cistos Odontogênicos , Humanos , Carcinoma Mucoepidermoide/patologia , Cisto Dentígero/patologia , Cistos Odontogênicos/patologia , Células Epiteliais/patologia , Metaplasia/patologia , Mucina-5AC , Mucina-2
10.
Vet Immunol Immunopathol ; 271: 110740, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38537313

RESUMO

Intestinal mucus barrier disruption may occur with chronic inflammatory enteropathies. The lack of studies evaluating mucus health in dogs with chronic colitis arises from inherent challenges with assessment of the intestinal mucus layer. It is therefore unknown if reduced goblet cell (GBC) numbers and/or mucin 2 (MUC2) expression, which are responsible for mucus production and secretion, correlate with inflammation severity in dogs with granulomatous colitis (GC) or lymphocytic-plasmacytic colitis (LPC). It is undetermined if Ki-67 immunoreactivity, which has been evaluated in dogs with small intestinal inflammation, similarly correlates to histologic severity in GC and LPC. Study objectives included comparing Ki-67 immunoreactivity, GBC population and MUC2 expression in dogs with GC, LPC and non-inflamed colon; and exploring the use of ribonucleic acid (RNAscope®) in-situ hybridization (ISH) to evaluate MUC2 expression in canine colon. Formalin-fixed endoscopic colonic biopsies were obtained from 48 dogs over an eight-year period. A blinded pathologist reviewed all biopsies. Dogs were classified into the GC (n=19), LPC (n=19) or no colitis (NC) (n=10) group based on final histopathological diagnosis. Ki-67 immunohistochemistry, Alcian-Blue/PAS staining to highlight GBCs, and RNAscope® ISH using customized canine MUC2-targeted probes were performed. At least five microscopic fields per dog were selected to measure Ki-67 labelling index (KI67%), GBC staining percentage (GBC%) and MUC2 expression (MUC2%) using image analysis software. Spearman's correlation coefficients were used to determine associations between World Small Animal Veterinary Association histologic score (WHS) and measured variables. Linear regression models were used to compare relationships between WHS with KI67%, GBC%, and MUC2%; and between GBC% and MUC2%. Median WHS was highest in dogs with GC. Median KI67% normalised to WHS was highest in the NC group (6.69%; range, 1.70-23.60%). Median GBC% did not correlate with colonic inflammation overall. Median MUC2% normalised to WHS in the NC group (10.02%; range, 3.05-39.09%) was two- and three-fold higher than in the GC and LPC groups respectively. With increased colonic inflammation, despite minimal changes in GBC% overall, MUC2 expression markedly declined in the LPC group (-27.4%; 95%-CI, -49.8, 5.9%) and mildly declined in the GC and NC groups. Granulomatous colitis and LPC likely involve different pathways regulating MUC2 expression. Decreased MUC2 gene expression is observed in dogs with chronic colitis compared to dogs without colonic signs. Changes in MUC2 expression appear influenced by GBC activity rather than quantity in GC and LPC.


Assuntos
Colite , Doenças do Cão , Células Caliciformes , Antígeno Ki-67 , Mucina-2 , Animais , Cães , Mucina-2/genética , Mucina-2/metabolismo , Células Caliciformes/patologia , Células Caliciformes/metabolismo , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Doenças do Cão/metabolismo , Doenças do Cão/genética , Doenças do Cão/imunologia , Colite/veterinária , Colite/patologia , Feminino , Masculino , Colo/patologia , Granuloma/veterinária , Granuloma/patologia , Imuno-Histoquímica/veterinária
11.
Int J Biol Macromol ; 266(Pt 1): 131232, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554896

RESUMO

Inflammatory bowel diseases (IBD) are chronic inflammatory conditions characterized by disruptions in the colonic mucus barrier and gut microbiota. In this study, a novel soluble polysaccharide obtained from Boletus aereus (BAP) through water extraction was examined for its structure. The protective effects of BAP on colitis were investigated using a DSS-induced mice model. BAP was found to promote the expression of intestinal mucosal and tight junction proteins, restore the compromised mucus barrier, and suppress the activation of inflammatory signaling. Moreover, BAP reshape the gut microbiota and had a positive impact on the composition of the gut microbiota by reducing inflammation-related microbes. Additionally, BAP decreased cytokine levels through the MANF-BATF2 signaling pathway. Correlation analysis revealed that MANF was negatively correlated with the DAI and the level of cytokines. Furthermore, the depletion of gut microbiota using antibiotic partially inhabited the effect of BAP on the activation of MANF and Muc2, indicating the role of gut microbiota in its protective effect against colitis. In conclusion, BAP had an obvious activation on MANF under gut inflammation. This provides new insights into the prospective use of BAP as a functional food to enhance intestinal health.


Assuntos
Colite , Sulfato de Dextrana , Microbioma Gastrointestinal , Mucina-2 , Transdução de Sinais , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Mucina-2/metabolismo , Mucina-2/genética , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Camundongos , Transdução de Sinais/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Modelos Animais de Doenças , Polissacarídeos/farmacologia , Polissacarídeos/química , Citocinas/metabolismo , Basidiomycota/química , Masculino , Polissacarídeos Fúngicos/farmacologia , Polissacarídeos Fúngicos/química
12.
Int J Mol Sci ; 25(4)2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38397081

RESUMO

We previously reported that an aryl hydrocarbon receptor (AhR) ligand, indole-3-carbinol (I3C), was effective at reducing colitis severity through immune cell-mediated interleukin-22 (IL-22) production. Intestinal epithelial cells (IECs) are also involved in regulating colitis, so we investigated their AhR-mediated mechanisms in the current report. A transcriptome analysis of IECs in wildtype (WT) mice revealed that during colitis, I3C regulated select mucin proteins, which could be attributed to goblet cell development. To address this, experiments under in vivo colitis (mice) or in vitro colon organoid conditions were undertaken to determine how select mucin proteins were altered in the absence or presence of AhR in IECs during I3C treatment. Comparing WT to IEC-specific AhR knockout mice (AhRΔIEC), the results showed that AhR expression was essential in IECs for I3C-mediated protection during colitis. AhR-deficiency also impaired mucin protein expression, particularly mucin 2 (Muc2), independently of IL-22. Collectively, this report highlights the important role of AhR in direct regulation of Muc2. These results provide justification for future studies aimed at determining how AhR might regulate select mucins through mechanisms such as direct transcription binding to enhance production.


Assuntos
Colite , Receptores de Hidrocarboneto Arílico , Animais , Camundongos , Mucina-2/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Interleucina 22 , Colite/genética , Mucinas/genética , Camundongos Endogâmicos C57BL
13.
Methods Mol Biol ; 2763: 71-78, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38347401

RESUMO

In the intestine, mucus covering the mucosa plays a critical role in maintaining gut homeostasis by protecting the mucosa from invasion by commensal bacteria. The gut mucus is composed primarily of MUC2 mucin secreted by goblet cells. MUC2 is highly O-glycosylated, and O-glycans are necessary for the function and polymer structure of MUC2. In addition, recent evidence revealed that several glycan modifications, such as sialylation and sulfation, confer resistance of mucins to proteolysis and affect the viscosity and lubricity of mucus. Therefore, characterizing glycan structures of mucins is required to understand their functions fully. In this chapter, we describe how to purify secreted mucins from the mammalian intestine for analysis of their glycan structures. This description includes the extraction of MUC2 mucin from the mucosal surface of the mouse colon and colon explants.


Assuntos
Mucosa Intestinal , Mucinas , Animais , Camundongos , Mucinas/química , Mucosa Intestinal/microbiologia , Mucina-2 , Células Caliciformes , Polissacarídeos , Mamíferos
14.
Int J Mol Sci ; 25(3)2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38339134

RESUMO

A structural weakness of the mucus barrier (MB) is thought to be a cause of ulcerative colitis (UC). This study aims to investigate the mucin (MUC) composition of MB in normal mucosa and UC. Ileocolonic biopsies were taken at disease onset and after treatment in 40 patients, including 20 with relapsing and 20 with remitting UC. Ileocolonic biopsies from 10 non-IBD patients were included as controls. Gut-specific MUC1, MUC2, MUC4, MUC5B, MUC12, MUC13, MUC15, and MUC17 were evaluated immunohistochemically. The promoters of mucin genes were also examined. Normal mucosa showed MUC2, MUC5B, and MUC13 in terminal ileum and colon, MUC17 in ileum, and MUC1, MUC4, MUC12, and MUC15 in colon. Membranous, cytoplasmic and vacuolar expressions were highlighted. Overall, the mucin expression was abnormal in UC. Derangements in MUC1, MUC4, and MUC5B were detected both at onset and after treatment. MUC2 and MUC13 were unaffected. Sequence analysis revealed glucocorticoid-responsive elements in the MUC1 promoter, retinoic-acid-responsive elements in the MUC4 promoter, and butyrate-responsive elements in the MUC5B promoter. In conclusion, MUCs exhibited distinct expression patterns in the gut. Their expression was disrupted in UC, regardless of the treatment protocols. Abnormal MUC1, MUC4, and MUC5B expression marked the barrier dysfunction in UC.


Assuntos
Colite Ulcerativa , Mucinas , Humanos , Mucinas/metabolismo , Colite Ulcerativa/genética , Colite Ulcerativa/patologia , Mucina-1/genética , Biópsia , Mucosa/metabolismo , Mucina-2/genética
15.
J Biol Chem ; 300(3): 105675, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272223

RESUMO

The O-glycoprotein Mucin-2 (MUC2) forms the protective colon mucus layer. While animal models have demonstrated the importance of Muc2, few studies have explored human MUC2 in similar depth. Recent studies have revealed that secreted MUC2 is bound to human feces. We hypothesized human fecal MUC2 (HF-MUC2) was accessible for purification and downstream structural and functional characterization. We tested this via histologic and quantitative imaging on human fecal sections; extraction from feces for proteomic and O-glycomic characterization; and functional studies via growth and metabolic assays in vitro. Quantitative imaging of solid fecal sections showed a continuous mucus layer of varying thickness along human fecal sections with barrier functions intact. Lectin profiling showed HF-MUC2 bound several lectins but was weak to absent for Ulex europaeus 1 (α1,2 fucose-binding) and Sambucus nigra agglutinin (α2,6 sialic acid-binding), and did not have obvious b1/b2 barrier layers. HF-MUC2 separated by electrophoresis showed high molecular weight glycoprotein bands (∼1-2 MDa). Proteomics and Western analysis confirmed the enrichment of MUC2 and potential MUC2-associated proteins in HF-MUC2 extracts. MUC2 O-glycomics revealed diverse fucosylation, moderate sialylation, and little sulfation versus porcine colonic MUC2 and murine fecal Muc2. O-glycans were functional and supported the growth of Bacteroides thetaiotaomicron (B. theta) and short-chain fatty acid (SCFA) production in vitro. MUC2 could be similarly analyzed from inflammatory bowel disease stools, which displayed an altered glycomic profile and differential growth and SCFA production by B. theta versus healthy samples. These studies describe a new non-invasive platform for human MUC2 characterization in health and disease.


Assuntos
Colo , Fezes , Proteômica , Animais , Humanos , Camundongos , Colo/metabolismo , Glicoproteínas/metabolismo , Mucosa Intestinal/metabolismo , Mucina-2/genética , Mucina-2/metabolismo , Muco/metabolismo , Suínos , Masculino , Camundongos Endogâmicos C57BL , Microbioma Gastrointestinal
16.
Microbiol Res ; 281: 127599, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38219635

RESUMO

The colonic mucus layer plays a critical role in maintaining the integrity of the colonic mucosal barrier, serving as the primary defense against colonic microorganisms. Predominantly composed of mucin 2 (MUC2), a glycosylation-rich protein, the mucus layer forms a gel-like coating that covers the colonic epithelium surface. This layer provides a habitat for intestinal microorganisms, which can utilize mucin glycans present in the mucus layer as a sustainable source of nutrients. Additionally, metabolites produced by the microbiota during the metabolism of mucus glycans have a profound impact on host health. Under normal conditions, the production and consumption of mucus maintain a dynamic balance. However, several studies have demonstrated that certain factors, such as dietary fiber deficiency, can enhance the metabolism of mucus glycans by gut bacteria, thereby disturbing this balance and weakening the mucus barrier function of the mucus layer. To better understand the occurrence and development of colon-related diseases, it is crucial to investigate the complex metabolic patterns of mucus glycosylation by intestinal microorganisms. Our objective was to comprehensively review these patterns in order to clarify the effects of mucus layer glycan metabolism by intestinal microorganisms on the host.


Assuntos
Formigas , Mucosa Intestinal , Animais , Mucosa Intestinal/metabolismo , Muco/metabolismo , Mucina-2/metabolismo , Mucinas/metabolismo , Colo/metabolismo , Colo/microbiologia , Polissacarídeos/metabolismo , Formigas/metabolismo
17.
Am J Surg Pathol ; 48(2): 127-139, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38062562

RESUMO

Small bowel adenocarcinoma (SBA) is rare, and scant data exist regarding its molecular and clinicopathologic characteristics. This study aimed to clarify the correlation between immunophenotypes, DNA mismatch repair status, genomic profiling, and clinicopathologic characteristics in patients with SBA. We examined 68 surgical resections from patients with primary SBA for immunohistochemical analyses of CK7, CK20, CD10, CDX2, MUC1, MUC2, MUC4, MUC5AC, and MUC6 expression as well as mismatch repair status. Genomic profiling was performed on 30 cases using targeted next-generation sequencing. Tumor mucin phenotypes were classified as gastric, intestinal, gastrointestinal, or null based on MUC2, MUC5AC, MUC6, and CD10 immunostaining. The expression of these proteins was categorized into 3 classifications according to their relationship to: (1) tumor location: CK7/CK20, MUC4, and MUC6; (2) histologic type: mucinous adenocarcinoma was positive for MUC2 and negative for MUC6; and (3) TNM stage: CD10 was downregulated, whereas MUC1 was upregulated in advanced TNM stages. CDX2 was a specific marker for SBA generally expressed in the small intestine. MUC1 and MUC4 expression was significantly associated with worse prognosis. MUC2 expression correlated with better prognosis, except for mucinous adenocarcinoma. Although the difference was not statistically significant, gastric-type tumors were more frequently located in the duodenum and were absent in the ileum. APC and CTNNB1 mutations were not found in the gastric-type tumors. The SBA immunophenotype correlated with tumor location, biological behavior, and genomic alterations. Our results suggest that the molecular pathway involved in carcinogenesis of gastric-type SBA differs from that of intestinal-type SBA.


Assuntos
Adenocarcinoma Mucinoso , Adenocarcinoma , Neoplasias Duodenais , Humanos , Mucina-2/análise , Mucina-2/genética , Mucina-2/metabolismo , Perfil Genético , Biomarcadores Tumorais/análise , Adenocarcinoma/genética , Adenocarcinoma Mucinoso/patologia , Intestino Delgado/patologia
18.
J Ethnopharmacol ; 322: 117555, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38110130

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The herb pair Astragali Radix (AR) and Curcumae Rhizoma (vinegar-processed, VPCR), derived from the traditional Chinese medicine (TCM) text 'Yixuezhongzhongcanxilu', have long been used to treat gastrointestinal diseases, notably colitis-associated colorectal cancer (CAC). Hedysari Radix (HR), belonging to the same Leguminosae family as AR but from a different genus, is traditionally used as a substitute for AR when paired with VPCR in the treatment of CAC. However, the optimal compatibility ratio for HR-VPCR against CAC and the underlying mechanisms remain unclear. AIM OF THE STUDY: To investigate the optimal compatibility ratio and underlying mechanisms of HR-VPCR against CAC using a combination of comparative pharmacodynamics, network pharmacology, and experimental verification. MATERIALS AND METHODS: The efficacy of different compatibility ratios of HR-VPCR against CAC was evaluated using various indicators, including the body weight, colon length, tumor count, survival rate, disease activity index (DAI) score, Haemotoxylin and Eosin (H&E) pathological sections, inflammation cytokines (IL-1ß, IL-6, IL-10, TNF-α), tumor markers (K-Ras, p53), and intestinal permeability proteins (claudin-1, E-cadherin, mucin-2). Then, the optimal compatibility ratio of HR-VPCR against CAC was determined based on the fuzzy matter-element analysis by integrating the above indicators. After high-performance liquid chromatography (HPLC) analysis for the optimal compatibility ratio of HR-VPCR, potential active components of HR-VPCR were identified by TCMSP and the previous bibliographies. Swiss Targets and GeneCards were adopted to predict the targets of the active components and the targets of CAC, respectively. Then, the common targets of HR-VPCR against CAC were obtained by Venn analysis. PPI networks were constructed in STRING. GO and KEGG enrichments were visualized by the David database. Finally, the predicted pathway was experimentally validated via Western blot. RESULTS: Various compatibility ratios of HR-VPCR demonstrated notable therapeutic effects to some extent, evidenced by improvements in body weight, colon length, tumor count, pathological symptoms (DAI score), colon and organ indexes, survival rate, and modulation of inflammation factors (IL-1ß, IL-6, IL-10, TNF-α), as well as tumor markers (K-Ras, p53), and down-regulation of intestinal permeability proteins (claudin-1, E-cadherin, mucin-2) in CAC mice. Among these ratios, the ratio 4:1 represents the optimal compatibility ratio by the fuzzy matter-element analysis. Thirty active components of HR-VPCR were carefully selected, targeting 553 specific genes. Simultaneously, 2022 targets associated with CAC were identified. 88 common targets were identified after generating a Venn plot. Following PPI network analysis, 29 core targets were established, with AKT1 ranking highest among them. Further analysis via GO and KEGG enrichment identified the PI3K-AKT signaling pathway as a potential mechanism. Experimental validation confirmed that HR-VPCR intervention effectively reversed the activated PI3K-AKT signaling pathway. CONCLUSIONS: The optimal compatibility ratio for the HR-VPCR herb pair in alleviating CAC is 4:1. HR-VPCR exerts its effects by alleviating intestinal inflammation, improving intestinal permeability, and regulating the PI3K-AKT signaling pathway.


Assuntos
Astrágalo , Neoplasias Associadas a Colite , Medicamentos de Ervas Chinesas , Animais , Camundongos , Interleucina-10 , Mucina-2 , Farmacologia em Rede , Claudina-1 , Interleucina-6 , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Fator de Necrose Tumoral alfa , Proteína Supressora de Tumor p53 , Biomarcadores Tumorais , Peso Corporal , Caderinas , Inflamação/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Simulação de Acoplamento Molecular
19.
Phytomedicine ; 121: 155115, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37801896

RESUMO

BACKGROUND: Evodia Rutaecarpa-processed Coptidis Rhizoma (ECR) is a traditional Chinese medicine for the treatment of ulcerative colitis (UC) in China. However, the mechanisms underlying the ECR processing are not elucidated. PURPOSE: Coptidis Rhizoma (CR) regulates the gut microbiota in the treatment of gastrointestinal diseases. This study explored the mechanism of action of ECR before and after processing in UC in view of the regulation of gut microecology. STUDY DESIGN: A preclinical experimental investigation was performed using a mouse model of UC to examine the regulatory effect of ECR and its mechanisms through gut microbiota analysis and metabolomic assays. METHODS: Mice received 4% dextran sulfate sodium to establish a UC model and treated with ECR and CR. Colonic histopathology and inflammatory changes were observed. Gut microbiota was analyzed using 16 s rRNA sequencing. Transplants of Lactobacillus reuteri were used to explore the correlation between ECR processing and the gut microbiota. The expression of mucin-2, Lgr5, and PCNA in colonic epithelial cells was measured using immunofluorescence. Wnt3a and ß-catenin levels were detected by western blotting. The metabolites in the colon tissue were analyzed using a targeted energy metabolomic assay. The effect of energy metabolite α-ketoglutarate (α-KG) on L. reuteri growth and UC were verified in mice. RESULTS: ECR improved the effects on UC in mice compared to CR, including alleviating colonic injury and inflammation, and modulating gut microbiota by increasing L. reuteri level. L. reuteri dose-dependently alleviated colonic injury, increased mucin-2 level, and promoted colonic epithelial regeneration by increasing Lgr5 and PCNA expression. This was consistent with the results before and after ECR processing. L. reuteri promoted epithelial regeneration by upregulating Wnt/ß-catenin pathway. Moreover, ECR increased metabolites levels (especially α-KG) to promote energy metabolism in the colon tissue compared to CR. α-KG treatment increased L. reuteri level and alleviated mucosal damage in UC mice. It promoted L. reuteri growth by increasing the energy metabolic status by enhancing α-KG dehydrogenase activity. CONCLUSION: ECR processing improves the therapeutic effects of UC via the α-KG-L. reuteri-epithelial regeneration axis.


Assuntos
Colite Ulcerativa , Colite , Medicamentos de Ervas Chinesas , Evodia , Limosilactobacillus reuteri , Animais , Camundongos , Colite Ulcerativa/tratamento farmacológico , Ácidos Cetoglutáricos , Medicamentos de Ervas Chinesas/farmacologia , Mucina-2 , beta Catenina , Antígeno Nuclear de Célula em Proliferação , Colo , Modelos Animais de Doenças , Sulfato de Dextrana , Camundongos Endogâmicos C57BL
20.
J Anim Sci ; 1012023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37606553

RESUMO

Zinc (Zn) is an essential trace element that has physiological and nutritional functions. However, excessive use of Zn can lead to waste of resources. In this study, we compared the effects of inorganic (ZnSO4) and organic Zn glycine chelate (Zn-Gly) on the growth performance, intestinal morphology, immune function, barrier integrity, and gut microbiome of Cherry Valley ducks. We randomly divided 180 one-day-old male meat ducks into three groups, each with six replicates of 10 birds: basal diet group (CON), basal diet with 70 mg Zn/kg from ZnSO4 (ZnSO4 group), and basal diet with 70 mg Zn/kg from Zn-Gly (Zn-Gly group). After 14 and 35 d of feeding, birds in the Zn groups had significantly increased body weight and average daily gain (ADG), decreased intestinal permeability indicator d-lactate, improved intestinal morphology and barrier function-related tight junction protein levels, and upregulated mucin 2 and secretory immunoglobulin A levels compared to the control (P < 0.05). Additionally, compared to the ZnSO4 group, we found that supplementation with Zn-Gly at 70 mg/kg Zn resulted in the significant increase of body weight at 35 d, 1 to 35 d ADG and average daily feed intake, villus height at 14 and 35 d, secretory immunoglobulin A and immunoglobulin G at 14 d, and mucin 2 mRNA level at 14 d (P < 0.05). Compared with the control group, dietary Zn had a significant effect on the gene expression of metallothionein at 14 and 35 d (P < 0.05). 16S rRNA sequencing showed that Zn significantly increased alpha diversity (P < 0.05), whereas no differences in beta diversity were observed among groups (P > 0.05). Dietary Zn significantly altered the cecal microbiota composition by increasing the abundances of Firmicutes, Blautia, Lactobacillus, Prevotellaceae NK3B31, and [Ruminococcus] torques group and reducing that of Bacteroides (P < 0.05). Spearman correlation analysis revealed that the changes in microbiota were highly correlated (P < 0.05) with growth performance, intestinal morphology, and immune function-related parameters. Taken together, our data show that, under the condition of adding 70 mg/kg Zn, supplementation with Zn-Gly promoted growth performance by regulating intestinal morphology, immune function, barrier integrity, and gut microbiota of Cherry Valley ducks compared with the use of ZnSO4 in feed.


Zinc (Zn) is an essential trace element that is required for physiological and nutritional functions, but excessive use of Zn can lead to environmental pollution. Few studies have directly compared the impact of different Zn sources on growth performance and intestinal barrier function in Cherry Valley ducks. This study was conducted to investigate the effects of two sources of Zn (inorganic ZnSO4 or organic Zn glycine chelate, Zn-Gly) on growth performance, intestinal morphology, barrier function, and gut microbiome of ducks. Compared to the ZnSO4 group, we found that supplementation with Zn-Gly resulted in the significant increase of body weight at 35 d, 1 to 35 d average daily gain and average daily feed intake, villus height at 14 and 35 d, secretory immunoglobulin A and immunoglobulin G at 14 d, and mucin 2 mRNA level at 14 d. At the genus level, the relative abundance of Blautia was higher in the Zn-Gly group than that in the control and ZnSO4 group. Therefore, Zn-Gly supplementation at 70 mg/kg Zn had positive effects in promoting growth performance by regulating intestinal morphology, barrier function, and gut microbiota of ducks when compared with the same dosage use of ZnSO4 in feed.


Assuntos
Microbioma Gastrointestinal , Masculino , Animais , Patos , Zinco , Mucina-2 , RNA Ribossômico 16S , Glicina/farmacologia , Peso Corporal
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