Mucin Production Research Articles

Bioaccessibility and Bioactivity of Cereal Polyphenols: A Review.

Cereal bioactive compounds, especially polyphenols, are known to possess a wide range of disease preventive properties that are attributed to their antioxidant and anti-inflammatory activity. However, due to their low plasma concentrations after oral intake, there is controversy regarding their therapeutic benefits in vivo. Within the gastrointestinal tract, some cereal polyphenols are absorbed in the small intestine, with the majority accumulating and metabolised by the colonic microbiota. Chemical and enzymatic processes occurring during gastrointestinal digestion modulate the bioactivity and bioaccessibility of phenolic compounds. The interactions between the cereal polyphenols and the intestinal epithelium allow the modulation of intestinal barrier function through antioxidant, anti-inflammatory activity and mucin production thereby improving intestinal health. The intestinal microbiota is believed to have a reciprocal interaction with polyphenols, wherein the microbiome produces bioactive and bioaccessible phenolic metabolites and the phenolic compound, in turn, modifies the microbiome composition favourably. Thus, the microbiome presents a key link between polyphenol consumption and the health benefits observed in metabolic conditions in numerous studies. This review will explore the therapeutic value of cereal polyphenols in conjunction with their bioaccessibility, impact on intestinal barrier function and interaction with the microbiome coupled with plasma anti-inflammatory effects.

Value of histopathology in predicting microsatellite instability in colorectal cancer

Background: Identifying colorectal cancers (CRCs) with high levels of microsatellite instability (MSI-H) is clinically important. Few studies reported the role of histology in identifying MSI-H colorectal carcinomas. Hence the present study was undertaken to assess the value of histopathology in predicting MSI-H and its correlation with histopathologic prognostic features in CRC. Methods: Total 100 histo-pathologically confirmed cases of CRC were enrolled in the study. Tumour’s histopathological typing, staging, and sizing was conducted based on WHO criteria. Tumour grade, extent of mucin production, tumour growth pattern and presence of a Crohn’s like inflammatory infiltrate were determined. For immunohistochemistry (IHC) we used monoclonal antibodies (ES05 or 25D12). Results: Among 100 tumour samples, loss of MLH1 or MSH2 expression was detected in 13(13%) cases (MSI tumours) while 87(87%) tumours showed normal expression for MLH1 and MSH2 immuno-reactivity (MSS tumours). In terms of MSI/MSS status of tumour samples, statistical analysis showed that abnormal MMR protein expression was associated with tumour site, side of colon with cancer, size of tumour, tumour infiltrating lymphocytes and crohn’s like inflammatory infiltrate. Some histopathological and clinical features that appeared highly specific but much less sensitive in predicting MSI include stage, and some features were more sensitive and less specific which include tumour differentiation, CLR, TIL, dirty necrosis and pushing margin. Conclusion: MSI is an important prognostic factor in CRC and an important predictive factor of CRC chemotherapeutic treatment and outcome efficacy. Also result of the study is not consistent in describing various histopathological and clinical features in predicting MSI, CRC.

Epithelium-derived IL17A Promotes Cigarette Smoke-induced Inflammation and Mucus Hyperproduction.

The airway epithelium is a central modulator of innate and adaptive immunity in the lung. IL17A expression was found to be increased in the airway epithelium; however, the role of epithelium-derived IL17A in chronic obstructive pulmonary disease (COPD) remains unclear. In this study, we aimed to determine whether epithelium-derived IL17A regulates inflammation and mucus hyperproduction in COPD by using a cultured human bronchial epithelial (HBE) cell line invitro and an airway epithelium IL17A-specific knockout mouse invivo. Increased IL17A expression was observed in the mouse airway epithelium upon cigarette smoke (CS) exposure or in a mouse model of COPD that was induced by using CS and Eln (elastin). CS extract (CSE) also triggered IL17A expression in HBE cells. Blocking IL17A or IL17RA (IL17 receptor A) effectively attenuated CSE-induced MUC5AC and the inflammatory cytokines IL6, TNF-α, and IL1β in HBE cells, suggesting that IL17A mediates CSE-induced inflammation and mucin production in an autocrine manner. CSE activated p-JUN (phospho-JUN) and p-JNK (phospho-c-Jun N-terminal kinase), which were also reduced by IL17RA siRNA, and JUN siRNA attenuated CSE-induced IL6 and MUC5AC. In vivo, selective knockout of IL17A in the airway epithelium markedly reduced the neutrophilic infiltration in BAL fluid, peribronchial inflammation, proinflammatory mediators (CXCL1 [CXC ligand 1] and CXCL2), and mucus production in a COPD mouse model. We showed a novel function of airway epithelium-derived IL17A, which can act locally in an autocrine manner to amplify inflammation and increase mucus production in COPD pathogenesis.

Hypoxia and heat stress affect epithelial integrity in a Caco-2/HT-29 co-culture

Hypoxia and hyperthermia, which can be induced by high environmental temperature or strenuous exercise, are two common stressors that affect intestinal epithelial integrity and lead to multiple clinical symptoms. In this study, we developed an in-vitro intestinal monolayer model using two human colonic epithelial cell lines, Caco-2 and HT-29, co-cultured in Transwell inserts, and investigated the effects of heat treatment and/or hypoxia on the epithelial barrier function. The monolayer with a ratio of 9:1 (Caco-2:HT-29) showed high trans-epithelial electrical resistance (TEER), low Lucifer Yellow permeability and high mucin production. Hyperthermia and/or hypoxia exposure (2 h) triggered heat shock and oxidative stress responses. HSP-70 and HSF-1 protein levels were up-regulated by hyperthermia, which were further enhanced when hyperthermia was combined with hypoxia. Increased HIF-1α protein expression and Nrf2 nuclear translocation was only caused by hypoxia. Hyperthermia and/or hypoxia exposure disrupted the established monolayer by increasing paracellular permeability, decreasing ZO-1, claudin-3 and occludin protein/mRNA expression, while enhancing E-cadherin protein expression. Tight junction protein distribution in the monolayer was also modulated by the hyperthermia and/or hypoxia exposure. In addition, transcription levels of mucin genes, MUC-2 and MUC-5AC, were increased after 2 h of hyperthermia and/or hypoxia exposure. In conclusion, this Caco-2/HT-29 cell model is valid and effective for studying detrimental effects of hyperthermia and/or hypoxia on intestinal barrier function and related heat shock and oxidative stress pathways and can be used to investigate possible interventions to reverse hyperthermia and/or hypoxia-induced intestinal epithelial injury.

Autophagy of mucin granules contributes to resolution of airway mucous metaplasia

Exacerbations of muco-obstructive airway diseases such as COPD and asthma are associated with epithelial changes termed mucous metaplasia (MM). Many molecular pathways triggering MM have been identified; however, the factors that regulate resolution are less well understood. We hypothesized that the autophagy pathway is required for resolution of MM by eliminating excess non-secreted intracellular mucin granules. We found increased intracellular levels of mucins Muc5ac and Muc5b in mice deficient in autophagy regulatory protein, Atg16L1, and that this difference was not due to defects in the known baseline or stimulated mucin secretion pathways. Instead, we found that, in mucous secretory cells, Lc3/Lamp1 vesicles colocalized with mucin granules particularly adjacent to the nucleus, suggesting that some granules were being eliminated in the autophagy pathway rather than secreted. Using a mouse model of MM resolution, we found increased lysosomal proteolytic activity that peaked in the days after mucin production began to decline. In purified lysosomal fractions, Atg16L1-deficient mice had reduced proteolytic degradation of Lc3 and Sqstm1 and persistent accumulation of mucin granules associated with impaired resolution of mucous metaplasia. In normal and COPD derived human airway epithelial cells (AECs), activation of autophagy by mTOR inhibition led to a reduction of intracellular mucin granules in AECs. Our findings indicate that during peak and resolution phases of MM, autophagy activity rather than secretion is required for elimination of some remaining mucin granules. Manipulation of autophagy activation offers a therapeutic target to speed resolution of MM in airway disease exacerbations.

Clostridium butyricum Induces the Production and Glycosylation of Mucins in HT-29 Cells.

C. butyricum is a common gut commensal bacterium, which has many positive functions in human intestine. In this study, we investigated the effects of monosaccharide and its derivatives on the adhesion of C. butyricum to the mucus of HT-29 cells. RNA interference was performed to assess the roles of MUC2 and glycan in the adhesion of C. butyricum to HT-29 cells. The effects of C. butyricum on the glycosylation of mucins were assayed with fluorescence microscope. The expression levels of mucins and glycotransferases were also determined. The results showed that C. butyricum could adhere to the mucins secreted by HT-29 cells. Several kinds of monosaccharides inhibited the adhesion of C. butyricum to HT-29 cells, which suggested that the mucus glycan was the attaching sites of this bacterium. Knockdown of MUC2, FUT2 or GALNT7 significantly decreased the numbers of the bacteria adhering to HT-29 cells. When colonizing on the surface of HT-29 cells, C. butyricum could increase the production of mucins, promote the expression of glycotransferase, and induce the glycosylation of mucins. These results demonstrated that the glycan of mucus played important roles in the adhesion of C. butyricum to HT-29 cells. This study indicates for the first time that C. butyricum possesses the ability to modulate the glycosylation profile of mucus secreted by HT-29 cells. These findings contribute to understanding the mechanism of interaction between colonic epithelial cells and commensal bacteria.

Platycodin D attenuates airway inflammation via suppression Th2 transcription factor in a murine model of acute asthma

Introduction: Bronchial asthma is a common chronic inflammatory condition of the airway tissue. Platycodin D (PLD) has antiinflammatory effects in a mouse model of allergic asthma. In this work, the anti-asthma potential of PLD was studied by investigation of its effect to suppress airway inflammation and mucin production, a murine model of asthma and the possible mechanisms. Methods: Mice were randomly assigned to five experimental groups: control, ovalbumin (OVA), OVA+ICS (intranasal fluticasone), OVA+PLD and OVA+PLD/ICS. Airway histological studies were evaluated by the H&E staining; IL-4, IL-5, and IL-13 in bronchoalveolar lavage fluid were evaluated by ELISA; GATA3 and IRF4 mRNA of airway were measured by RT-PCR and their protein level were measured by Western blotting. Results: Our study showed that PLD suppressed eosinophilic inflammation and mucin production in bronchial mucosa. Moreover, PLD inhibited production of Th2 cytokines such as IL-4, IL-5, and IL-13. Protein production of GATA3 and IRF4, were also decreased in PLD treated OVA asthma model. Taken together, our results provided evidence that PLD inhibits the airway inflammation via suppression of Th2 transcription factor production. Conclusion: These findings suggest that PLD may effectively ameliorate the progression of asthma. These results suggest that PLD could be used as a therapy for allergic asthma.

Utility of Insulinoma-Associated Protein 1 (INSM1) and Mucin 2 (MUC2) Immunohistochemistry in the Distinction of Endocrine Mucin-Producing Sweat Gland Carcinoma From Morphologic Mimics.

Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is a rare low-grade adnexal malignancy with a predilection for the eyelids of elderly White women, which is associated with invasive mucinous carcinoma with endocrine features in one-third of cases. EMPSGC is characterized by the presence of neuroendocrine differentiation and mucin production. However, EMPSGC displays a variety of architectural patterns including solid, cribriform, papillary, and cystic growth. In addition, EMPSGC may also display nonendocrine cytologic features, such as apocrine change. Because of their variable appearance, EMPSGC can show significant morphologic overlap with certain histologic mimics, namely basal cell carcinoma, hidrocystoma, apocrine hidradenoma, and tubular adenoma. In addition, the often limited sampling of this anatomically delicate area can make the diagnosis of EMPSGC challenging. EMPSGC expresses neuroendocrine markers, including synaptophysin and chromogranin, often in a focal distribution. However, insulinoma-associated protein 1 (INSM1) has been found to be a more sensitive marker for EMPSGC. Recent studies have also demonstrated the expression of the gel-forming mucin 2 (MUC2) in EMPSGC, possibly signifying a lacrimal or conjunctival origin of these neoplasms. In this article, we discuss EMPSGC in the context of its histologic mimics (BCC, hidrocystoma, apocrine hidradenoma, and tubular adenoma) and we investigate the utility of the immunohistochemical expression of INSM1 and MUC2 in the distinction of EMPSGC from them. We demonstrate that INSM1 and MUC2 can reliably distinguish EMPSGC from these histologic mimics.

Resveratrol inhibits MUC5AC expression by regulating SPDEF in lung cancer cells

BackgroundMUC5AC was recently identified to play important roles in the proliferation and metastasis of malignant mucinous lung tumor cells. Resveratrol (Res), a natural compound with anticancer effects in lung cancer cells, has been reported to inhibit mucin production in airway epithelial cells. This study aimed to investigate the inhibitory effect of Res on MUC5AC expression in lung mucinous adenocarcinoma cells and the potential mechanisms. MethodsMucus-producing A549 human lung carcinoma cells were used to test the effects of Res on SPDEF and MUC5AC expression. Gene and protein expression was assessed by real-time quantitative PCR (qPCR), immunofluorescence and western blotting assays. SPDEF lentivirus was used to upregulate SPDEF expression levels in mucus-producing A549 human lung carcinoma cells. Cell proliferation was assessed by Cell Counting Kit-8 (CCK-8) assay. ResultsRes decreased MUC5AC expression in an SPDEF-dependent manner in mucus-producing A549 human lung carcinoma cells, and this change was accompanied by decreased ERK expression and AKT pathway activation. Moreover, SPDEF was found to be overexpressed in lung adenocarcinoma (LUAD), especially in mucinous adenocarcinoma. In-vitro functional assays showed that overexpression of SPDEF reduced the chemosensitivity of A549 cells to cisplatin (DDP). In addition, Res treatment increased A549 cell chemosensitivity to DDP by inhibiting the SPDEF-MUC5AC axis. ConclusionOur results indicate that the SPDEF-MUC5AC axis is associated with DDP sensitivity, and that Res decreases SPDEF and MUC5AC expression by inhibiting ERK and AKT signaling in A549 cells, which provides a potential pharmacotherapy for the prevention and therapeutic management of mucinous adenocarcinoma.

A pan-cancer analysis of MUC family genes as potential biomarkers for immune checkpoint therapy.

2598 Background: Mucin (MUC) is a family of high-molecular weight glycoproteins and increased mucin production occurs in many malignant tumors. Recent studies have found relationship between mutations of some MUC family genes and efficacy of immunotherapy. Here, we explored the associations of MUC family genes (MUC2, MUC3A, MUC4, MUC5B, MUC6, MUC12, MUC16, MUC17, MUC19) mutation with ICI response based on multidimensional data from multiple solid tumors. Methods: 15 solid tumor types of TCGA genomic data for 6138 patients was used to evaluate tumor mutational burden (TMB) differences between MUC family genes mutation group and wildtype group. TMB was calculated as the total count of nonsynonymous mutations in coding sequence. Neoantigens of 3039 samples across 11 solid tumor types were obtained from The Cancer Immunome Atlas. A pan-cancer immunotherapy cohort (Broad/Dana-Farber, Nat Genet 2018, N = 249) was used to explore the relationship between mutations of MUC family genes and its efficacy of immunotherapy. Results: The most common mutated MUC genes (frequency > 5%) were MUC16 (25.3%), MUC17 (10.8%), MUC5B (10.5%), MUC4 (8.6%), and MUC2 (5.1%). The data between MUC mutation group and wild type group showed a significant difference (P < 0.01) in TMB. Median TMB across fifteen tumors in MUC mutation group and wild type group is 7.04 mutations per Mb and 2.07 mutations per Mb, separately. The TNB between two group is also showed a significant difference (P < 0.01). Median TNB across nine types tumor in MUC mutation group and wild type group is 121.5 neoantigens and 34.0 neoantigens, separately. A multivariable analysis across the pan-cancer cohort using Cox proportional-hazards regression demonstrated that KMT2C mutation was associated with better OS (hazard ratio, 0.66; 95%CI, 0.45-0.99; P = 0.042), adjusting for sex and cancer type. Conclusions: The results indicated that MUC family genes mutation was associated with a higher TMB and TNB. Analysis of immunotherapy cohort data showed MUC family was associated with better OS. These findings indicate that these genes mutation may serve as a predictive biomarker for ICI in solid tumor patients.

Nanosecond pulsed electric fields impair viability and mucin expression in mucinous colorectal carcinoma cell

Nanosecond pulsed electric fields (nsPEFs) are a non-thermal technology that can induce a myriad of biological responses and changes in cellular physiology. nsPEFs have gained significant attention as a novel cancer therapy. However, studies investigating the application of nsPEF in mucinous carcinomas are scarce. In this study, we explored several biological responses in two mucinous colorectal adenocarcinoma cell lines, LS 174T and HT-29, to nsPEF treatment. We determined the overall cell survival and viability rates following nsPEF treatment using CCK-8 and colony formation assays. We measured the intracellular effects of nsPEF treatment by analyzing cell cycle distribution, cell apoptosis and mitochondrial potential. We also analyzed mucin production at both mRNA and protein levels. Our results showed that nsPEF treatment significantly reduced mucinous cell viability in a dose-dependent manner. nsPEF treatment increased cell cycles arrest at G0/G1 while the proportion of G2/M cells gradually decreased. Cell apoptosis increased following nsPEF treatment with a clear loss in mitochondrial membrane potential. Furthermore, the protein expression of functional mucin family members decreased after nsPEF treatment. In conclusion, nsPEF treatment reduced MCRC cell viability, cell proliferation, and mucin protein production while promoted apoptosis. Our work is a pilot study that projects some insights into the potential clinical applications of nsPEFs in treating mucinous colorectal carcinoma.

VEGF receptor 2 (KDR) protects airways from mucus metaplasia through a Sox9-dependent pathway.

Mucus-secreting goblet cells are the dominant cell type in pulmonary diseases, e.g., asthma and cystic fibrosis (CF), leading to pathologic mucus metaplasia and airway obstruction. Cytokines including IL-13 are the major players in the transdifferentiation of club cells into goblet cells. Unexpectedly, we have uncovered a previously undescribed pathway promoting mucous metaplasia that involves VEGFa and its receptor KDR. Single-cell RNA sequencing analysis coupled with genetic mouse modeling demonstrates that loss of epithelial VEGFa, KDR, or MEK/ERK kinase promotes excessive club-to-goblet transdifferentiation during development and regeneration. Sox9 is required for goblet cell differentiation following Kdr inhibition in both mouse and human club cells. Significantly, airway mucous metaplasia in asthmatic and CF patients is also associated with reduced KDR signaling and increased SOX9 expression. Together, these findings reveal an unexpected role for VEGFa/KDR signaling in the defense against mucous metaplasia, offering a potential therapeutic target for this common airway pathology.

Effects induced by polyethylene microplastics oral exposure on colon mucin release, inflammation, gut microflora composition and metabolism in mice

Microplastics are plastic fragments widely distributed in the environment and accumulate in the organisms. However, the research on microplastics effects in mammals is limited. Polyethylene is the main kind of microplastics in the environment. We hypothesized that polyethylene exposure disrupts host intestine metabolism by modifying intestine microflora composition and then lipopolysaccharide (LPS) pathway. Female mice were orally exposed to 0, 0.002 and 0.2 μg/g/d polyethylene microplastics (PE MPs) for 30 days. Colon mucin density was quantized after AB-PAS staining. Mucin 2 (MUC2), inflammatory factors (IL-1β, IL-6, IL-8 and IL-10), short-chain fatty acid receptors (GPR41 and GPR43), LPS receptors (TLR4 and MyD88) and LPS pathway downstream genes (ERK1 and NF-κB) mRNA levels in colon were measured. Feces were collected on the 15th day of exposure for gut microflora analysis. Blood biochemical analysis was performed. Results showed that 0.2 μg/g/d PE MPs exposure significantly decreased colon mucin expression (p < 0.05), decreased IL-1β (p < 0.05) and increased IL-8 and IL-10 levels (p < 0.01 and p < 0.001 respectively). Microflora data showed that in 0.2 μg/g/d PE MPs group the number of Firmicutes decreased and the number of Bacteroides increased (both p < 0.01). Predicted KEGG metabolic pathways by piecrust method indicated that PE MPs enhanced amino acids metabolism in microflora. ERK1 and NF-κB mRNA were significantly lower in 0.2 μg/g/d PE MPs group (both p < 0.001). Blood total protein, albumin and globulin levels significantly increased after 0.2 μg/g/d PE MPs exposure (p < 0.01, p < 0.01 and p < 0.05 respectively). These results indicate that PE MPs exposure induced decreased mucin production, a slight immune response and increased the microflora amino acid metabolism in the mice colon by modifying colon microflora composition. SummaryPolyethylene microplastics exposure decreased colon mucin release and increased amino acid metabolism by modifying colon microflora composition.

Bronchial gene expression signature associated with rate of subsequent FEV1 decline in individuals with and at risk of COPD

BackgroundCOPD is characterised by progressive lung function decline. Leveraging prior work demonstrating bronchial airway COPD-associated gene expression alterations, we sought to determine if there are alterations associated with differences in...

Septum submucosal glands exhibit aberrant morphology and reduced mucin production in chronic rhinosinusitis.

Chronic rhinosinusitis (CRS) is characterized by significant accumulation and thickening of mucus in the sinonasal cavities. One contributor of aberrant mucus production and impaired mucociliary clearance (MCC) is altered function of the sinonasal submucosal glands (SMGs), yet contributions of SMGs to upper airway disease initiation and progression remain unknown. The objective of this study was to characterize the morphology and secretory cell identities of the nasal septum SMGs in both healthy and CRS adults. Biopsies from adult participants with CRS without nasal polyps (CRSsNP, n=4), CRS with nasal polyps (CRSwNP, n=8), and non-CRS controls (n=14) were collected from the posterior septum. Glandular morphology and mucus markers were investigated using histological techniques and high-resolution confocal microscopy. Analysis revealed a significant decrease in gland density in the posterior septum of CRSsNP (28%±6.15%) and CRSwNP (23%±3.09%) compared to control participants (53%±1.59%, p<0.0001). Further analysis of the CRS SMG secretory function revealed an overall decrease in Mucin 5B+ gland mucus being produced. Dilated and cystic ductal structures filled with inspissated mucus were also common to CRS glands. Here, we describe a significant alteration in SMG structure and function in the adult CRS posterior septum suggesting reduced gland contribution to MCC. The SMGs of both the nose and sinuses may represent targets for future therapeutic approaches.

LncRNA Interacts With STAT6 Upon IL13/IL4 Activation In Asthma Inflammation

Long non-coding RNAs (lncRNAs), have been implicated in inflammation, cancer and autoimmune diseases. They interact with epithelial cells in the lungs and impact inflammatory response elicited by cytokines IL-13/IL-4 (interleukins 13 and 4) through the JAK/STAT (Janus kinase/signal transducer and activation of transcription) signaling pathway however, little is known about the impact of lncRNAs in asthma inflammatory responses. Airway epithelial cells deficient in some specific lncRNAs in literature have been discovered to express increased STAT signaling following IL-13 stimulation therefore we hypothesize a direct interaction of some RNAs with STAT6 upon binding to DNA during IL-13/STAT6 activation. Critical to type 2 asthma inflammatory responses initiated by IL-13/IL-4 stimulation in bronchial cells is STAT6 which causes cellular differentiation, hyperplasia, and mucin production in concert with airway remodeling. Discovering more about the signal transducer will improve current knowledge of pathophysiology of this subset of asthma. Inactive STAT6 lies in the cytosol until it is phosphorylated and translocated to the nucleus where it binds DNA and activates transcription. It becomes phosphorylated and dimerizes upon IL-4/IL-13 binding to the receptor, and after that STAT6 signaling cascade evolves to activate downstream genes by binding DNA with other protein complexes. Regulatory networks involve in signal transduction systems comprise RNAs that are directly involved in the expression JAK/STAT downstream genes during inflammatory responses. Until now it has not been discovered how 1L-13 initiates differentiation upon activation of STAT6 hence discovering other interactomes upon STAT6 binding DNA is paramount. We intend to use proximal protein interaction mechanisms to identify critical players in STAT6 transcription activation and then use mass spectrometry to identify the interacting biomolecules and the state of interaction and then determine how the loss of these biomolecules impacts STAT6 activation using ChIP-Seq.

Human iPSC Colonoid Function is Improved by Exposure to Fecal Fermentates

The host-microbe interaction is critical for intestinal homeostasis. By-products from microbial metabolism of unabsorbed dietary components have been studied increasingly as potential contributors to health and disease. In vitro fermentation systems provide a way to simulate microbial activity and by-product production of the colon using human fecal samples. Objectives of the study were to determine how clarified supernatants from two different fermentation conditions affect markers of cell proliferation, differentiation, barrier function, and immune function in a human induced pluripotent (iPSC) colon organoid model. Short-chain and branch-chain fatty acid concentrations of the supernatants were analyzed and were similar to known in vivo concentrations. Molecular results showed 25% of the clarified supernatant from batch fermentation led to a more physiological intestinal phenotype including increased markers of differentiation, including alkaline phosphatase, chromogranin-A, SCFA transport monocarboxylate transporter-1, (6.2-fold, 2.1-fold, 1.8-fold, respectively; P<0.05). Mucin production (mucin-2, mucin-4) was increased in cells treated with 25% supernatant, as observed by confocal microscopy. In addition, increased tight junction expression (claudin-3) was noted by immunofluorescence in 25% supernatant treated cells. A dose-response increase in barrier function was observed over the 72-hour time course, with a 2-fold increase in transepithelial electrical resistance (TER) in the 25% group compared to the control group (P<0.05). To further investigate host effects, clarified supernatants from a continuous multi-stage fermentation representing the ascending (AC), transverse (TC), and descending (DC) colonic domains were utilized and some regional differences were observed including increased markers of inflammation (IL-1β, 6.15pg/mL; IL-6, 27.58pg/mL; TNFα, 4.49pg/mL; P < 0.05) in DC treated samples only. Overall, clarified supernatants represent a valuable model to examine effects of microbial by-products on host intestinal development and function and future efforts will be designed to further understand microbial communities and metabolites, along with additional host response measures.

Effects of empagliflozin against indomethacin induced gastric mucosa.

Sodium-glucose cotransporter 2 (SGLT2) inhibitors (SGLT2i) are considered a new class antidiabetic agent, as well as lowering blood sugar, it has many positive effects. This study aimed to investigate the effects of SLGT2i on the gastric mucosa. We investigated the effects of empagliflozin on indomethacin-induced gastritis using 48 male Wistar Albino rats. We performed histopathological evaluations of gastric mucosa tissue. And we studied the levels of serum disulfide, native thiol, total thiol, and ischemia modified albumin, disulfide/native thiol ratio (SSSH), native thiol/total thiol percent ratio (SH total SH), and disulfide/total thiol percent ratio (SS total SH). We found that empagliflozin increased mucin production in rat gastric mucosa. Besides, we observed milder inflammation findings and lower gastritis scores in the empagliflozin receiving groups than the placebo groups. Native thiol, total thiol, and disulfide levels were lower in the indomethacin-induced gastritis groups. This study is the first to investigate the effect of empagliflozin on the gastrointestinal tract in a rat model. We concluded that empagliflozin increased mucin production and revealed positive effects in an indomethacin-induced gastritis model.

4-CMTB Ameliorates Ovalbumin-Induced Allergic Asthma through FFA2 Activation in Mice.

Free fatty acid receptor 2 (FFA2, also known as GPR43), a G-protein-coupled receptor, has been known to recognize short-chain fatty acids and regulate inflammatory responses. FFA2 gene deficiency exacerbated disease states in several models of inflammatory conditions including asthma. However, in vivo efficacy of FFA2 agonists has not been tested in allergic asthma. Thus, we investigated effect of 4-chloro-α-(1-methylethyl)-N-2-thiazoylylbenzeneacetanilide (4-CMTB), a FFA2 agonist, on antigen-induced degranulation in RBL-2H3 cells and ovalbumin-induced allergic asthma in BALB/c mice. Treatment of 4-CMTB inhibited the antigen-induced degranulation concentration-dependently. Administration of 4-CMTB decreased the immune cell numbers in the bronchoalveolar lavage fluid and suppressed the expression of inflammatory Th2 cytokines (IL-4, IL-5, and IL-13) in the lung tissues. Histological studies revealed that 4-CMTB suppressed mucin production and inflammation in the lungs. Thus, results proved that FFA2 functions to suppress allergic asthma, suggesting 4-CMTB activation of FFA2 as a therapeutic tool for allergic asthma.

Berberine, a potential prebiotic to indirectly promote Akkermansia growth through stimulating gut mucin secretion

BackgroundAkkermansia spp. plays important roles in maintenance of host health. Increasing evidence reveals that berberine (BBR) may exert its pharmacological effects via, at least partially, promotion of Akkermansia spp. However, how BBR stimulates Akkermansia remains largely unknown. PurposeIn this study, we investigated the mechanism underlying the Akkermansia-promoting effect of BBR. Materials and methodsThe effect of BBR on Akkermansia was assessed in BBR-gavaged mice and direct incubation. The influence of BBR on intestinal mucin production was determined by alcian-blue staining and real-time PCR. The feces were analysis by gas chromatography–time-of-flight mass spectrometry (GC-TOF/MS) metabolomics. The role of polyamines in BBR-elicited mucin secretion and Akkermansia growth was evaluated by administration of difluoromethylornithine (DFMO) in mice. ResultsGavage of BBR dose-dependently and time-dependently increased the abundance of Akkermansia in mice. However, it did not stimulate Akkermansia growth in direct incubation, suggesting that BBR may promote Akkermansia in a host-dependent way. Oral administration of BBR significantly increased the transcription of mucin-producing genes and mucin secretion in colon. Untargeted metabolomics analysis showed that BBR increased polyamines production in feces which are known to stimulate goblet cell proliferation and differentiation, but treatment with eukaryotic polyamine synthase inhibitor DFMO did not abolish the stimulating effect of BBR on mucin secretion and Akkermansia growth, indicating that the gut bacteria-derived but not the host-derived polyamines may involve in the BBR-promoted Akkermansia growth. ConclusionsOur results reveal that BBR is a promising prebiotic for Akkermansia, and it promotes Akkermansia growth via stimulating mucin secretion in colon.