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1.
Front Cell Infect Microbiol ; 14: 1391758, 2024.
Article in English | MEDLINE | ID: mdl-38716194

ABSTRACT

Campylobacter jejuni, a Gram-negative bacterium, is one of the most common causes of foodborne illness worldwide. Its adhesion mechanism is mediated by several bacterial factors, including flagellum, protein adhesins, lipooligosaccharides, proteases, and host factors, such as surface glycans on epithelial cells and mucins. Fungal lectins, specialized carbohydrate-binding proteins, can bind to specific glycans on host and bacterial cells and thus influence pathogenesis. In this study, we investigated the effects of fungal lectins and protease inhibitors on the adhesion of C. jejuni to model biotic surfaces (mucin, fibronectin, and collagen) and Caco-2 cells as well as the invasion of Caco-2 cells. The lectins Marasmius oreades agglutinin (MOA) and Laccaria bicolor tectonin 2 (Tec2) showed remarkable efficacy in all experiments. In addition, different pre-incubations of lectins with C. jejuni or Caco-2 cells significantly inhibited the ability of C. jejuni to adhere to and invade Caco-2 cells, but to varying degrees. Pre-incubation of Caco-2 cells with selected lectins reduced the number of invasive C. jejuni cells the most, while simultaneous incubation showed the greatest reduction in adherent C. jejuni cells. These results suggest that fungal lectins are a promising tool for the prevention and treatment of C. jejuni infections. Furthermore, this study highlights the potential of fungi as a rich reservoir for novel anti-adhesive agents.


Subject(s)
Bacterial Adhesion , Campylobacter jejuni , Lectins , Protease Inhibitors , Campylobacter jejuni/drug effects , Campylobacter jejuni/physiology , Campylobacter jejuni/metabolism , Humans , Caco-2 Cells , Bacterial Adhesion/drug effects , Lectins/metabolism , Lectins/pharmacology , Protease Inhibitors/pharmacology , Protease Inhibitors/metabolism , Fungi/drug effects , Mucins/metabolism , Epithelial Cells/microbiology , Fibronectins/metabolism
2.
Food Res Int ; 183: 114185, 2024 May.
Article in English | MEDLINE | ID: mdl-38760122

ABSTRACT

Low- and no-calorie sweeteners reduce the amount of carbohydrates in foods and beverages. However, concerns about taste perception surrounding the role of non-nutritive sweeteners in the oral cavity remain unanswered. One of the parameters that influences taste perception is the diffusion coefficient of the sweetener molecules inside the mucin layer lining the mouth. This study investigated the impact of diffusion coefficients of common high-intensity sweeteners on taste perception focusing on the sweeteners' diffusion through mucin. Transwell Permeable Support well plates were used to measure diffusion coefficients of samples that were collected at specific intervals to estimate the coefficients based on concentration measurements. The diffusion coefficients of acesulfame-K, aspartame, rebaudioside M, sucralose, and sucrose with and without NaCl were compared. We found that different sweeteners show different diffusion behavior through mucin and that the presence of salt enhances the diffusion. These findings contribute insights into the diffusion of high-intensity sweeteners, offer a way to evaluate diffusion coefficients in real-time, and inform the development of products with improved taste profiles.


Subject(s)
Mucins , Sucrose , Sweetening Agents , Diffusion , Mucins/metabolism , Sucrose/analogs & derivatives , Taste Perception , Humans , Thiazines
3.
Sheng Wu Gong Cheng Xue Bao ; 40(5): 1498-1508, 2024 May 25.
Article in Chinese | MEDLINE | ID: mdl-38783811

ABSTRACT

To investigate the role of recombinant mussel mucin in wound healing, we aimed to prepare this mucin using Pichia pastoris as the host microbe. Our method involved constructing a genetically engineered strain of P. pastoris that expressed a fusion protein consisting of Mfp-3 and preCol-P peptide segments of mussel. After fermentation and purification, we obtained a pure recombinant mussel mucin product. We then conducted experiments to evaluate its effect at both the cellular and animal levels. At the cellular level, we examined its impact on the proliferation and migration of mouse fibroblast L929. At the animal level, we assessed its ability to promote wound healing after full-layer skin resection in rats. Our results showed that the recombinant mussel mucin protein has a content of 90.28% and a purity of 96.49%. The content of 3,4-dihydroxyphenylalanine (DOPA) was 0.73 wt%, and the endotoxin content was less than 0.5 EU/mg. Importantly, the recombinant mussel mucin protein significantly promoted both the migration and proliferation of mouse fibroblast, as well as the wound healing in rat skin. In conclusion, our findings demonstrate that recombinant mussel mucin has the potential to promote wound healing and can be considered a promising medical biomaterial.


Subject(s)
Wound Healing , Animals , Wound Healing/drug effects , Rats , Mice , Mucins/metabolism , Mucins/genetics , Bivalvia , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , Recombinant Proteins/pharmacology , Fibroblasts/metabolism , Fibroblasts/drug effects , Cell Movement/drug effects , Cell Proliferation/drug effects , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/pharmacology , Male , Rats, Sprague-Dawley , Saccharomycetales
4.
Parasite Immunol ; 46(5): e13040, 2024 May.
Article in English | MEDLINE | ID: mdl-38801355

ABSTRACT

Cystic echinococcosis is caused by the tissue-dwelling larva (hydatid) of Echinococcus granulosus sensu lato. A salient feature is that this larva is protected by the acellular laminated layer (LL). As the parasite grows, the LL sheds abundant particles that can accumulate in the parasite's vicinity. The potential of LL particles to induce inflammation in vivo has not been specifically analysed. It is not known how each of its two major components, namely highly glycosylated mucins and calcium inositol hexakisphosphate (InsP6) deposits, impacts inflammation induced by the LL as a whole. In this work, we show that LL particles injected intraperitoneally cause infiltration of eosinophils, neutrophils and monocytes/macrophages as well as the disappearance of resident (large peritoneal) macrophages. Strikingly, the absence of calcium InsP6 enhanced the recruitment of all the inflammatory cell types analysed. In contrast, oxidation of the mucin carbohydrates caused decreased recruitment of neutrophils. The carbohydrate-oxidised particles caused cell influx nonetheless, which may be explained by possible receptor-independent effects of LL particles on innate immune cells, as suggested by previous works from our group. In summary, LL particles can induce acute inflammatory cell recruitment partly dependent on its mucin glycans, and this recruitment is attenuated by the calcium InsP6 component.


Subject(s)
Echinococcus granulosus , Phytic Acid , Animals , Echinococcus granulosus/immunology , Phytic Acid/pharmacology , Phytic Acid/metabolism , Echinococcosis/immunology , Echinococcosis/parasitology , Inflammation , Neutrophils/immunology , Mucins/metabolism , Mice , Macrophages/immunology , Macrophages/metabolism , Eosinophils/immunology , Female , Larva/immunology
5.
Gut Microbes ; 16(1): 2356270, 2024.
Article in English | MEDLINE | ID: mdl-38797998

ABSTRACT

High-fat diets alter gut barrier integrity, leading to endotoxemia by impacting epithelial functions and inducing endoplasmic reticulum (ER) stress in intestinal secretory goblet cells. Indeed, ER stress, which is an important contributor to many chronic diseases such as obesity and obesity-related disorders, leads to altered synthesis and secretion of mucins that form the protective mucus barrier. In the present study, we investigated the relative contribution of omega-3 polyunsaturated fatty acid (PUFAs)-modified microbiota to alleviating alterations in intestinal mucus layer thickness and preserving gut barrier integrity. Male fat-1 transgenic mice (exhibiting endogenous omega-3 PUFAs tissue enrichment) and wild-type (WT) littermates were fed either an obesogenic high-fat diet (HFD) or a control diet. Unlike WT mice, HFD-fed fat-1 mice were protected against mucus layer alterations as well as an ER stress-mediated decrease in mucin expression. Moreover, cecal microbiota transferred from fat-1 to WT mice prevented changes in the colonic mucus layer mainly through colonic ER stress downregulation. These findings highlight a novel feature of the preventive effects of omega-3 fatty acids against intestinal permeability in obesity-related conditions.


Subject(s)
Colon , Diet, High-Fat , Endoplasmic Reticulum Stress , Fatty Acids, Omega-3 , Gastrointestinal Microbiome , Intestinal Mucosa , Mice, Transgenic , Animals , Diet, High-Fat/adverse effects , Mice , Male , Fatty Acids, Omega-3/metabolism , Colon/microbiology , Colon/metabolism , Intestinal Mucosa/metabolism , Intestinal Mucosa/microbiology , Obesity/metabolism , Obesity/microbiology , Mucus/metabolism , Mice, Inbred C57BL , Mucins/metabolism , Goblet Cells/metabolism , Fecal Microbiota Transplantation
6.
Cell Rep ; 43(5): 114206, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38733584

ABSTRACT

The interleukin (IL)-22 cytokine can be protective or inflammatory in the intestine. It is unclear if IL-22 receptor (IL-22Ra1)-mediated protection involves a specific type of intestinal epithelial cell (IEC). By using a range of IEC type-specific Il22Ra1 conditional knockout mice and a dextran sulfate sodium (DSS) colitis model, we demonstrate that IL-22Ra1 signaling in MATH1+ cells (goblet and progenitor cells) is essential for maintaining the mucosal barrier and intestinal tissue regeneration. The IL-22Ra1 signaling in IECs promotes mucin core-2 O-glycan extension and induces beta-1,3-galactosyltransferase 5 (B3GALT5) expression in the colon. Adenovirus-mediated expression of B3galt5 is sufficient to rescue Il22Ra1IEC mice from DSS colitis. Additionally, we observe a reduction in the expression of B3GALT5 and the Tn antigen, which indicates defective mucin O-glycan, in the colon tissue of patients with ulcerative colitis. Lastly, IL-22Ra1 signaling in MATH1+ progenitor cells promotes organoid regeneration after DSS injury. Our findings suggest that IL-22-dependent protective responses involve O-glycan modification, proliferation, and differentiation in MATH1+ progenitor cells.


Subject(s)
Colitis , Dextran Sulfate , Interleukin-22 , Interleukins , Receptors, Interleukin , Animals , Interleukins/metabolism , Mice , Glycosylation , Colitis/metabolism , Colitis/pathology , Colitis/chemically induced , Receptors, Interleukin/metabolism , Mucins/metabolism , Basic Helix-Loop-Helix Transcription Factors/metabolism , Humans , Signal Transduction , Mice, Inbred C57BL , Inflammation/pathology , Inflammation/metabolism , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Mice, Knockout , Galactosyltransferases/metabolism , Galactosyltransferases/genetics , Stem Cells/metabolism
7.
Nat Commun ; 15(1): 4582, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38811534

ABSTRACT

The intestinal anaerobic bacterium Akkermansia muciniphila is specialized in the degradation of mucins, which are heavily O-glycosylated proteins that constitute the major components of the mucus lining the intestine. Despite that adhesion to mucins is considered critical for the persistence of A. muciniphila in the human intestinal tract, our knowledge of how this intestinal symbiont recognizes and binds to mucins is still limited. Here, we first show that the mucin-binding properties of A. muciniphila are independent of environmental oxygen concentrations and not abolished by pasteurization. We then dissected the mucin-binding properties of pasteurized A. muciniphila by use of a recently developed cell-based mucin array that enables display of the tandem repeats of human mucins with distinct O-glycan patterns and structures. We found that A. muciniphila recognizes the unsialylated LacNAc (Galß1-4GlcNAcß1-R) disaccharide selectively on core2 and core3 O-glycans. This disaccharide epitope is abundantly found on human colonic mucins capped by sialic acids, and we demonstrated that endogenous A. muciniphila neuraminidase activity can uncover the epitope and promote binding. In summary, our study provides insights into the mucin-binding properties important for colonization of a key mucin-foraging bacterium.


Subject(s)
Akkermansia , Mucins , Polysaccharides , Akkermansia/metabolism , Humans , Mucins/metabolism , Polysaccharides/metabolism , Neuraminidase/metabolism , Protein Binding , Glycosylation , Disaccharides/metabolism , Verrucomicrobia/metabolism , Epitopes/metabolism , Bacterial Adhesion
8.
J Phys Chem A ; 128(15): 3015-3023, 2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38593044

ABSTRACT

Respiratory viruses, such as influenza and severe acute respiratory syndrome coronavirus 2, represent a substantial public health burden and are largely transmitted through respiratory droplets and aerosols. Environmental factors such as relative humidity (RH) and temperature impact virus transmission rates, and a precise mechanistic understanding of the connection between these environmental factors and virus transmission would improve efforts to mitigate respiratory disease transmission. Previous studies on supermicrometer particles observed RH-dependent phase transitions and linked particle phase state to virus viability. Phase transitions in atmospheric aerosols are dependent on size in the submicrometer range, and actual respiratory particles are expelled over a large size range, including submicrometer aerosols that can transmit diseases over long distances. Here, we directly investigated the phase transitions of submicrometer model respiratory aerosols. A probe molecule, Nile red, was added to particle systems including multiple mucin/salt mixtures, a growth medium, and simulated lung fluid. For each system, the polarity-dependent fluorescence emission was measured following RH conditioning. Notably, the fluorescence measurements of mucin/NaCl and Dulbecco's modified Eagle's medium particles indicated that liquid-liquid phase separation (LLPS) also occurs in submicron particles, suggesting that LLPS can also impact the viability of viruses in submicron particles and thus affect aerosol virus transmission. Furthermore, the utility of fluorescence-based measurements to study submicrometer respiratory particle physicochemical properties in situ is demonstrated.


Subject(s)
Mucins , Respiratory Aerosols and Droplets , Humidity , Aerosols/chemistry
9.
Vet Q ; 44(1): 1-18, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38606662

ABSTRACT

Complex respiratory diseases are a significant challenge for the livestock industry worldwide. These diseases considerably impact animal health and welfare and cause severe economic losses. One of the first lines of pathogen defense combines the respiratory tract mucus, a highly viscous material primarily composed of mucins, and a thriving multi-kingdom microbial ecosystem. The microbiome-mucin interplay protects from unwanted substances and organisms, but its dysfunction may enable pathogenic infections and the onset of respiratory disease. Emerging evidence also shows that noncoding regulatory RNAs might modulate the structure and function of the microbiome-mucin relationship. This opinion paper unearths the current understanding of the triangular relationship between mucins, the microbiome, and noncoding RNAs in the context of respiratory infections in animals of veterinary interest. There is a need to look at these molecular underpinnings that dictate distinct health and disease outcomes to implement effective prevention, surveillance, and timely intervention strategies tailored to the different epidemiological contexts.


Subject(s)
Microbiota , Respiratory Tract Diseases , Animals , Mucins/chemistry , Livestock , Respiratory Tract Diseases/veterinary
10.
Zhonghua Bing Li Xue Za Zhi ; 53(4): 351-357, 2024 Apr 08.
Article in Chinese | MEDLINE | ID: mdl-38556818

ABSTRACT

Objective: To investigate the clinicopathological and molecular genetic characteristics of Crohn's disease (CD). Methods: A retrospective analysis was conducted on 52 CD patients who underwent surgical resection at the First Affiliated Hospital of Nanjing Medical University between January 2014 and June 2023. Clinical presentations and histopathological features were assessed. Whole-genome sequencing was performed on 17 of the samples, followed by sequencing and pathway enrichment analyses. Immunohistochemistry was used to assess the expression of frequently mutated genes. Results: Among the 52 patients, 34 were males and 18 were females, male-to-female ratio was 1.9∶1.0, with a median age of 45 years at surgery and 35 years at diagnosis. According to the Montreal classification, A3 (51.9%,27/52), B2 (61.5%, 32/52), and L3 (50.0%,26/52) subtypes were the most predominant. Abdominal pain and diarrhea were the common symptoms. Histopathological features seen in all 52 patients included transmural inflammation, disruption of cryptal architecture, lymphoplasmacytic infiltration, varying degrees of submucosal fibrosis and thickening, increased enteric nerve fibers and neuronal proliferation. Mucosal defects, fissure ulcers, abscesses, pseudopolyps, and adenomatous proliferation were also observed in 51 (98.1%), 38 (73.1%), 28 (53.8%), 45 (86.5%), and 28 (53.8%) cases, respectively. Thirty-one (59.6%) cases had non-caseating granulomas, and 3 (5.8%) cases had intestinal mucosal glandular epithelial dysplasia. Molecular analysis showed that 12/17 CD patients exhibited mutations in at least one mucin family gene (MUC2, MUC3A, MUC4, MUC6, MUC12, MUC17), and MUC4 was the most frequently mutated in 7/17 of cases. Immunohistochemical stains showed reduced MUC4 expression in epithelial cells, with increased MUC4 expression in the epithelial surface, particularly around areas of inflammatory cell aggregation; and minimal expression in the lower half of the epithelium. Conclusions: CD exhibits diverse clinical and pathological features, necessitating a comprehensive multidimensional analysis for diagnosis. Mutations and expression alterations in mucin family genes, particularly MUC4, may play crucial roles in the pathogenesis of CD.


Subject(s)
Crohn Disease , Humans , Male , Female , Middle Aged , Crohn Disease/genetics , Crohn Disease/diagnosis , Crohn Disease/pathology , Retrospective Studies , Mucins , Epithelial Cells/pathology , Molecular Biology
11.
J Theor Biol ; 587: 111824, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38604595

ABSTRACT

The human gut microbiota relies on complex carbohydrates (glycans) for energy and growth, primarily dietary fiber and host-derived mucins. We introduce a mathematical model of a glycan generalist and a mucin specialist in a two-compartment chemostat model of the human colon. Our objective is to characterize the influence of dietary fiber and mucin supply on the abundance of mucin-degrading species within the gut ecosystem. Current mathematical gut reactor models that include the enzymatic degradation of glycans do not differentiate between glycan types and their degraders. The model we present distinguishes between a generalist that can degrade both dietary fiber and mucin, and a specialist species that can only degrade mucin. The integrity of the colonic mucus barrier is essential for overall human health and well-being, with the mucin specialist Akkermanisa muciniphila being associated with a healthy mucus layer. Competition, particularly between the specialist and generalists like Bacteroides thetaiotaomicron, may lead to mucus layer erosion, especially during periods of dietary fiber deprivation. Our model treats the colon as a gut reactor system, dividing it into two compartments that represent the lumen and the mucus of the gut, resulting in a complex system of ordinary differential equations with a large and uncertain parameter space. To understand the influence of model parameters on long-term behavior, we employ a random forest classifier, a supervised machine learning method. Additionally, a variance-based sensitivity analysis is utilized to determine the sensitivity of steady-state values to changes in model parameter inputs. By constructing this model, we can investigate the underlying mechanisms that control gut microbiota composition and function, free from confounding factors.


Subject(s)
Dietary Fiber , Gastrointestinal Microbiome , Models, Biological , Mucins , Mucus , Mucins/metabolism , Dietary Fiber/metabolism , Humans , Gastrointestinal Microbiome/physiology , Mucus/metabolism , Colon/metabolism , Colon/microbiology , Polysaccharides/metabolism
12.
Food Res Int ; 184: 114246, 2024 May.
Article in English | MEDLINE | ID: mdl-38609225

ABSTRACT

Food-derived mucins are glycoproteins rich in sialic acid, but their digestive properties and potential health benefits for humans have been scarcely investigated. In this work, ovomucin (OVM, rich in N-acetylneuraminic acid, about 3 %), porcine small intestinal mucin (PSIM, rich in N-glycolylneuraminic acid, about 1 %), the desialylated OVM (AOVM) and the desialylated PSIM (APSIM) were selected to examine their digestion and their impact on the gut microbiota of elderly individuals. The results shown that, the proportion of low-molecular-weight proteins increased after simulated digestion of these four mucins, with concomitant comparable antioxidant activity observed. Desialylation markedly increased the degradation and digestion rate of mucins. In vitro fecal fermentation was conducted with these mucins using fecal samples from individuals of different age groups: young, low-age and high-age elderly. Fecal fermentation with mucin digestive solution stimulated the production of organic acids in the group with fecal sample of the elderly individuals. Among them, the OVM group demonstrated the most favorable outcomes. The OVM and APSIM groups elevated the relative abundance of beneficial bacteria such as Lactobacillus and Bifidobacterium, while diminishing the presence of pathogenic bacteria such as Klebsiella. Conversely, the probiotic effects of AOVM and PSIM were attenuated or even exhibited adverse effects. Hence, mucins originating from different sources and possessing distinct glycosylation patterns exhibit diverse biological functions. Our findings can offer valuable insights for developing a well-balanced and nutritious diet tailored to the elderly population.


Subject(s)
Gastrointestinal Microbiome , Mucins , Humans , Aged , Animals , Swine , Diet , Food , Bifidobacterium
13.
Nat Microbiol ; 9(5): 1176-1188, 2024 May.
Article in English | MEDLINE | ID: mdl-38684911

ABSTRACT

Matching donor and recipient blood groups based on red blood cell (RBC) surface ABO glycans and antibodies in plasma is crucial to avoid potentially fatal reactions during transfusions. Enzymatic conversion of RBC glycans to the universal group O is an attractive solution to simplify blood logistics and prevent ABO-mismatched transfusions. The gut symbiont Akkermansia muciniphila can degrade mucin O-glycans including ABO epitopes. Here we biochemically evaluated 23 Akkermansia glycosyl hydrolases and identified exoglycosidase combinations which efficiently transformed both A and B antigens and four of their carbohydrate extensions. Enzymatic removal of canonical and extended ABO antigens on RBCs significantly improved compatibility with group O plasmas, compared to conversion of A or B antigens alone. Finally, structural analyses of two B-converting enzymes identified a previously unknown putative carbohydrate-binding module. This study demonstrates the potential utility of mucin-degrading gut bacteria as valuable sources of enzymes for production of universal blood for transfusions.


Subject(s)
ABO Blood-Group System , Akkermansia , Glycoside Hydrolases , ABO Blood-Group System/immunology , Humans , Glycoside Hydrolases/metabolism , Mucins/metabolism , Erythrocytes/immunology , Polysaccharides/metabolism , Gastrointestinal Microbiome , Blood Group Antigens/metabolism , Blood Group Antigens/immunology , Bacterial Proteins/metabolism , Bacterial Proteins/immunology
14.
J Trace Elem Med Biol ; 84: 127459, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38640745

ABSTRACT

Trace elements such as zinc, manganese, copper, or iron are essential for a wide range of physiological functions. It is therefore crucial to ensure an adequate supply of these elements to the body. Many previous investigations have dealt with the role of transport proteins, in particular their selectivity for, and competition between, different ions. Another so far less well investigated major factor influencing the absorption of trace elements seems to be the intestinal mucus layer. This gel-like substance covers the entire gastrointestinal tract and its physiochemical properties can be mainly assigned to the glycoproteins it contains, so-called mucins. Interaction with mucins has already been demonstrated for some metals. However, knowledge about the impact on the respective bioavailability and competition between those metals is still sketchy. This review therefore aims to summarize the findings and knowledge gaps about potential effects regarding the interaction between gastrointestinal mucins and the trace elements iron, zinc, manganese, and copper. Mucins play an indispensable role in the absorption of these trace elements in the neutral to slightly alkaline environment of the intestine, by keeping them in a soluble form that can be absorbed by enterocytes. Furthermore, the studies so far indicate that the competition between these trace elements for uptake already starts at the intestinal mucus layer, yet further research is required to completely understand this interaction.


Subject(s)
Copper , Intestinal Absorption , Intestinal Mucosa , Iron , Manganese , Zinc , Copper/metabolism , Humans , Zinc/metabolism , Manganese/metabolism , Iron/metabolism , Intestinal Absorption/physiology , Animals , Intestinal Mucosa/metabolism , Mucins/metabolism , Mucus/metabolism , Trace Elements/metabolism
15.
mSystems ; 9(5): e0024624, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38564708

ABSTRACT

Dietary fiber deprivation is linked to probiotic extinction, mucus barrier dysbiosis, and the overgrowth of mucin-degrading bacteria. However, whether and how mucin could rescue fiber deprivation-induced intestinal barrier defects remains largely unexplored. Here, we sought to investigate the potential role and mechanism by which exogenous mucin maintains the gut barrier function. The results showed that dietary mucin alleviated fiber deprivation-induced disruption of colonic barrier integrity and reduced spermine production in vivo. Importantly, we highlighted that microbial-derived spermine production, but not host-produced spermine, increased significantly after mucin supplementation, with a positive association with upgraded colonic Lactobacillus abundance. After employing an in vitro model, the microbial-derived spermine was consistently dominated by both mucin and Lactobacillus spp. Furthermore, Limosilactobacillus mucosae was identified as an essential spermine-producing Lactobacillus spp., and this isolated strain was responsible for spermine accumulation, especially after adhering to mucin in vitro. Specifically, the mucin-supplemented bacterial supernatant of Limosilactobacillus mucosae was verified to promote intestinal barrier functions through the increased spermine production with a dependence on enhanced arginine metabolism. Overall, these findings collectively provide evidence that mucin-modulated microbial arginine metabolism bridged the interplay between microbes and gut barrier function, illustrating possible implications for host gut health. IMPORTANCE: Microbial metabolites like short-chain fatty acids produced by dietary fiber fermentation have been demonstrated to have beneficial effects on intestinal health. However, it is essential to acknowledge that certain amino acids entering the colon can be metabolized by microorganisms to produce polyamines. The polyamines can promote the renewal of intestinal epithelial cell and maintain host-microbe homeostasis. Our study highlighted the specific enrichment by mucin on promoting the arginine metabolism in Limosilactobacillus mucosae to produce spermine, suggesting that microbial-derived polyamines support a significant enhancement on the goblet cell proliferation and barrier function.


Subject(s)
Arginine , Colon , Gastrointestinal Microbiome , Intestinal Mucosa , Mucins , Spermine , Spermine/metabolism , Mucins/metabolism , Arginine/metabolism , Arginine/pharmacology , Intestinal Mucosa/metabolism , Intestinal Mucosa/microbiology , Animals , Gastrointestinal Microbiome/physiology , Colon/microbiology , Colon/metabolism , Male , Mice , Lactobacillus/metabolism , Humans , Dietary Fiber/metabolism , Mice, Inbred C57BL
16.
Nutrients ; 16(7)2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38612988

ABSTRACT

The goblet cells of the gastrointestinal tract (GIT) produce glycoproteins called mucins that form a protective barrier from digestive contents and external stimuli. Recent evidence suggests that the milk fat globule membrane (MFGM) and its milk phospholipid component (MPL) can benefit the GIT through improving barrier function. Our objective was to compare the effects of two digested MFGM ingredients with or without dextran sodium sulfate (DSS)-induced barrier stress on mucin proteins. Co-cultured Caco-2/HT29-MTX intestinal cells were treated with in vitro digests of 2%, 5%, and 10% (w/v) MFGM or MPL alone for 6 h or followed by challenge with 2.5% DSS (6 h). Transepithelial electrical resistance and fluorescein isothiocyanate (FITC)-dextran (FD4) permeability measurements were used to measure changes in barrier integrity. Mucin characterization was performed using a combination of slot blotting techniques for secreted (MUC5AC, MUC2) and transmembrane (MUC3A, MUC1) mucins, scanning electron microscopy (SEM), and periodic acid Schiff (PAS)/Alcian blue staining. Digested MFGM and MPL prevented a DSS-induced reduction in secreted mucins, which corresponded to the prevention of DSS-induced increases in FD4 permeability. SEM and PAS/Alcian blue staining showed similar visual trends for secreted mucin production. A predictive bioinformatic approach was also used to identify potential KEGG pathways involved in MFGM-mediated mucosal maintenance under colitis conditions. This preliminary in silico evidence, combined with our in vitro findings, suggests the role of MFGM in inducing repair and maintenance of the mucosal barrier.


Subject(s)
Dextrans , Fluorescein-5-isothiocyanate/analogs & derivatives , Glycolipids , Glycoproteins , Lipid Droplets , Humans , Caco-2 Cells , Alcian Blue , Glycoproteins/pharmacology , Epithelial Cells , Mucins
17.
Int J Biol Macromol ; 265(Pt 2): 130839, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38490391

ABSTRACT

Mucus penetration is one of the physiologic barriers of inhalation and nanocarriers can effectively facilitate the permeation of drugs. The interactions between the nanocarriers and mucin are crucial for penetration across the mucus layer on the respiratory tract. In this study, we proposed a molecular dynamics (MD) simulation method for the screening of polysaccharides that acted as the surface modification materials for inhalable nano-preparations to facilitate mucus penetration. MD revealed all-atom interactions between the monomers of polysaccharides, including dextran (DEX)/hyaluronic acid (HA)/carboxymethyl chitosan (CMCS) and the human mucin protein MUC5AC (hMUC5AC). The obtained data showed that DEX formed stronger non-covalent bonds with hMUC5AC compared to HA and CMCS, which suggested that HA and CMCS had better mucus permeability than DEX. For the in vitro verification, HA/CMCS-coated liposomes and DEX/PEG-inserted liposomes were prepared. The results of mucin interactions and mucus penetration studies confirmed that HA and CMCS possessed the weakest interactions with mucin and facilitated the mucus penetration, which was in consistent with the data from MD simulation. This work may shed light on the MD simulation-based screening of surface modification materials for inhalable nano-preparations to facilitate mucus penetration.


Subject(s)
Liposomes , Molecular Dynamics Simulation , Humans , Liposomes/chemistry , Mucins/metabolism , Mucus/metabolism , Lung
18.
Anal Chem ; 96(13): 5242-5250, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38512228

ABSTRACT

Mucin-domain glycoproteins are densely O-glycosylated and play critical roles in a host of healthy and disease-driven biological functions. Previously, we developed a mucin-selective enrichment strategy by employing a catalytically inactive mucinase (StcE) conjugated to a solid support. While this method was effective, it suffered from low throughput and high sample requirements. Further, the elution step required boiling in SDS, thus necessitating an in-gel digest with trypsin. Here, we introduce innovative elution conditions amenable to mucinase digestion and downstream analysis using mass spectrometry. This increased throughput and lowered sample input while maintaining mucin selectivity and enhancing the glycopeptide signal. We then benchmarked this technique against different O-glycan binding moieties for their ability to enrich mucins from various cell lines and human serum. Overall, the new method outperformed our previous procedure and all of the other enrichment techniques tested. This allowed for the effective isolation of more mucin-domain glycoproteins, resulting in a high number of O-glycopeptides, thus enhancing our ability to analyze the mucinome.


Subject(s)
Glycoproteins , Mucins , Humans , Mucins/chemistry , Mass Spectrometry , Glycosylation , Glycopeptides/chemistry
19.
J Cosmet Dermatol ; 23(4): 1113-1121, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38429932

ABSTRACT

BACKGROUND: Snail mucin is becoming increasingly popular for its wide range of ingredients and potential benefits. Snail extract's widespread appearance in cosmetic formulations encourages an investigation into the medical and cosmetic benefits. AIMS: This study aims to explore current literature on the variety of snail mucin applications. Specifically, we present a review of the uses, global market estimates and projects, and limitations to snail mucin. METHODS: A literature search was conducted on PubMed reviewing snail mucin and their application in medical and dermatologic fields examining their uses. Economic reports were also investigated for Global Market estimates. RESULTS: The therapeutic use of snail mucin in medical fields has been studied as antimicrobial agents, drug delivery vehicles, antitumor agents, wound healing agents, and biomaterial coatings among others. Additionally, the use in cosmetic fields includes antiaging, hydrating, anti-acne, scarring, and hyperpigmentation treatments. It is important to highlight that most studies conducted were preclinical or small clinical studies, stressing the need for additional large-scale clinical trials to support these claims. Investigations into the global market found estimates ranging from $457 million to $1.2 billion with upward projections in the upcoming decade. Limitations include ethical habitats for collection, allergy investigation, and missing clinical studies. CONCLUSIONS: The findings presented here emphasize the expanding uses of snail mucin and its ingredients alongside a growing market cosmetic industry should consider. We also emphasize the need for appropriate clinical trials into the stated benefits of snail mucin to ensure consumer safety and ethical extraction of mucin.


Subject(s)
Cosmetics , Mucins , Skin , Humans , Biological Products/chemistry , Biological Products/therapeutic use , Cicatrix/drug therapy , Cosmetics/chemistry , Mucins/therapeutic use , Skin/drug effects , Snails/chemistry
20.
Nat Commun ; 15(1): 2611, 2024 Mar 23.
Article in English | MEDLINE | ID: mdl-38521783

ABSTRACT

The dense O-glycosylation of mucins plays an important role in the defensive properties of the mucus hydrogel. Aberrant glycosylation is often correlated with inflammation and pathology such as COPD, cancer, and Crohn's disease. The inherent complexity of glycans and the diversity in the O-core structure constitute fundamental challenges for the analysis of mucin-type O-glycans. Due to coexistence of multiple isomers, multidimensional workflows such as LC-MS are required. To separate the highly polar carbohydrates, porous graphitized carbon is often used as a stationary phase. However, LC-MS workflows are time-consuming and lack reproducibility. Here we present a rapid alternative for separating and identifying O-glycans released from mucins based on trapped ion mobility mass spectrometry. Compared to established LC-MS, the acquisition time is reduced from an hour to two minutes. To test the validity, the developed workflow was applied to sputum samples from cystic fibrosis patients to map O-glycosylation features associated with disease.


Subject(s)
Mucins , Tandem Mass Spectrometry , Humans , Mucins/metabolism , Tandem Mass Spectrometry/methods , Reproducibility of Results , Polysaccharides/chemistry , Glycosylation
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