Mucin 5AC Gene Expression Research Articles

Influence of zinc sulfate and threonine supplementation on mucin 5ac gene expression in the small intestine and intestinal mucosal morphology in broiler chickens

ABSTRACT A 42-day feeding trial was carried out to evaluate the effect of dietary supplementation of zinc and threonine on the integrity of intestinal mucosa and expression of intestinal mucin 5ac (MUC5AC) gene in broiler chickens. A total of 640-day-old Arbor Acres broiler chicks were allocated to four dietary treatments with eight replicates of 20 birds in a completely randomized design. The experimental diets included T0: control (standard diet), T1: standard diet + 40 mg/kg Zinc Sulfate (ZnSO4), T2: standard diet + 2% L-Threonine (L-Thr) and T3: standard diet + (40 mg/kg ZnSO4 + 0.2% L-Threonine (L-Thr)). During the starter phase, the average daily gain and body weight of birds fed the T1 diet was lower (p < 0.05) than T2 and T0. The villus height (VH) of the jejunum in T2 was longer (p < 0.05) than in T0 and T3. In the ileum, VH for T1 was longer (p < 0.05) than for T0. The MUC5AC mRNA expression in the duodenum at the starter phase was lower (p < 0.05) in T3 than in T2 while in the jejunum, T1 was higher (p < 0.05) than the other treatment groups. The supplementation of zinc and threonine in the diet can improve the intestinal integrity of broiler chickens.

Phenotypic Epithelial Changes in Laryngotracheal Stenosis.

Characterize and quantify epithelium in multiple etiologies of laryngotracheal stenosis (LTS) to better understand its role in pathogenesis. Controlled in vitro cohort study. Endoscopic brush biopsy samples of both normal (non-scar) and scar were obtained in four patients with idiopathic subglottic stenosis (iSGS) and four patients with iatrogenic LTS (iLTS). mRNA expression of basal, ciliary, and secretory cell markers were evaluated using quantitative PCR. Cricotracheal resection tissue samples (n=5 per group) were also collected, analyzed using quantitative immunohistochemistry, and compared with rapid autopsy tracheal samples. Both iSGS and iLTS-scar epithelium had reduced epithelial thickness compared with non-scar control epithelium (P = .0009 and P = .0011, respectively). Basal cell gene and protein expression for cytokeratin 14 was increased in iSGS-scar epithelium compared with iLTS or controls. Immunohistochemical expression of ciliary tubulin alpha 1, but not gene expression, was reduced in both iSGS and iLTS-scar epithelium compared with controls (P = .0184 and P = .0125, respectively). Both iSGS and iLTS-scar had reductions in Mucin 5AC gene expression (P = .0007 and P = .0035, respectively), an epithelial goblet cell marker, with reductions in secretory cells histologically (P < .0001). Compared with non-scar epithelium, the epithelium within iSGS and iLTS is morphologically abnormal. Although both iSGS and iLTS have reduced epithelial thickness, ciliary cells, and secretory cells, only iSGS had significant increases in pathological basal cell expression. These data suggest that the epithelium in iSGS and iLTS play a common role in the pathogenesis of fibrosis in these two etiologies of laryngotracheal stenosis. Tertiary referral center (2017-2020). NA Laryngoscope, 132:2194-2201, 2022.

Characterization of mucin gene expression and goblet cell proportion in inflammatory colorectal polyps in miniature dachshunds.

Hyperplastic goblet cells and abundant mucus are significant characteristics of inflammatory colorectal polyps (ICRPs) in miniature dachshunds. In this study, selected mucin gene expressions and goblet cell proportions were evaluated in miniature dachshunds with ICRPs and in healthy dogs. Mucin 2 (MUC2) gene expression was not significantly different among the groups, whereas mucin 5AC (MUC5AC) gene expression was significantly higher in the polypoid lesions than in healthy colonic mucosa. Although the percentage of goblet cells in the upper crypt regions did not significantly differ between the groups, that in the lower crypt regions was significantly decreased in polypoid lesions. In conclusion, increased MUC5AC gene expression and goblet cell proportion changes may be associated with the pathogenesis of ICRPs.

Gene expression profiles of pro-inflammatory mediators in the conjunctiva of patients with epiblepharon.

To investigate the gene expression of pro-inflammatory mediators in the conjunctiva of pediatric patients with epiblepharon in a case-control study. Twenty healthy controls and 15 pediatric patients with epiblepharon were enrolled from April 23, 2020 to June 15, 2020. Epiblepharon severity was divided into class I-III (least to moderate severity) and class IV (most severe). We obtained impression cytologic specimens from the medial palpebral conjunctiva of the participants to measure the gene expression of interleukin (IL)-1β, IL-6, matrix metalloproteinase 9 (MMP9), and mucin 5AC (MUC5AC) using quantitative reverse transcription polymerase chain reaction. The mean age in the epiblepharon group was 9years (range 7.5-11years), and that in the healthy control group was 9.5years (range 8-11.3years). IL-1β, IL-6, and MMP9 expression levels were 2.08 (p < 0.05), 2.11 (p < 0.05), and 2.48 (p < 0.05) fold higher, respectively, in the epiblepharon group than in the healthy control group. However, MUC5AC gene expression was not different between healthy subjects and patients with epiblepharon. IL-1β, IL-6, and MMP9 expression levels in class IV patients were 1.32 (p < 0.05), 1.77 (p < 0.05), and 1.98 (p < 0.05) fold higher, respectively, than in class I-III patients. Epiblepharon may induce chronic inflammatory changes in the conjunctiva in addition to corneal epithelial damage. Therefore, early corrective surgery should be considered to prevent conjunctival inflammation.

Benzo(a)pyrene induces MUC5AC expression through the AhR/mitochondrial ROS/ERK pathway in airway epithelial cells

ObjectivesBenzo(a)pyrene (BaP) is a ubiquitous air pollutants, and BaP exposure leads to a risk of respiratory diseases. The oversecretion of airway mucus and high expression of mucin 5AC (MUC5AC) are associated with common respiratory disorders caused by air pollution. We aimed to investigate the effect of BaP on MUC5AC expression, especially the mechanisms by which BaP induces MUC5AC gene expression. MethodsThe human airway epithelial cell NCI-H292 was used to test the effects of BaP on the expression of MUC5AC in vitro. MUC5AC mRNA and protein expression were assessed with real-time quantitative PCR, immunochemistry, and western blotting. A luciferase assay was conducted to detect the activity of the promoter. The total cellular ROS and mitochondrial ROS were measured by corresponding probes. Small-interfering RNAs were used for gene silencing. AhR-overexpressing cell lines were constructed by transfection with AhR overexpression lentivirus. ResultsWe found that BaP stimulation upregulated the MUC5AC mRNA and protein levels and activated the ERK pathway. Suppressing ERK with U0126 (an ERK inhibitor) or knocking down ERK with siRNA decreased BaP-induced MUC5AC expression. The luciferase activity transfected with the MUC5AC promoter and cAMP-response element (CRE) was increased after BaP treatment, whereas CREB siRNA suppressed the BaP-induced overexpression of MUC5AC. In addition, BaP increased mitochondrial ROS production, and Mito-TEMP, a mitochondrial ROS inhibitor, inhibited BaP-induced MUC5AC expression and ERK activation. BaP increased the mRNA levels of CYP1A1 and CYP1B1, while Alizarin, a CYP1s inhibitor, suppressed the effects of BaP, including the MUC5AC overexpression, ERK activation and mitochondrial ROS generation. BaP induced the translocation of aryl hydrocarbon receptor (AhR) from the cytoplasm to the nucleus. SiRNA-mediated knockdown or chemical inhibition of AhR decreased the BaP-induced expression of MUC5AC, while the overexpression of AhR significantly enhanced the BaP-induced expression of MUC5AC. ITE, an endogenous AhR ligand, also upregulated the mRNA and protein expression of MUC5AC. Furthermore, resveratrol treatment inhibited the BaP-induced MUC5AC overexpression, AhR translocation, mitochondrial ROS production and ERK pathway activation. ConclusionHere, we highlighted the crucial role of AhR/mitochondrial ROS/ERK pathway activation in BaP-induced MUC5AC overexpression and identified resveratrol as a promising drug to reduce BaP-induced MUC5AC overexpression.

DFSG, a novel herbal cocktail with anti-asthma activity, suppressed MUC5AC in A549 cells and alleviated allergic airway hypersensitivity and inflammatory cell infiltration in a chronic asthma mouse model

Aim of the studyTo develop a novel anti-asthma drug. DFSG is a novel herbal cocktail composed of 4 types of herbal medicines. This study explored whether DFSG has the potential to attenuate asthma symptom severity and aimed to determine the immunomodulatory mechanism of DFSG using a chronic asthmatic mouse model induced by repeated challenges with Dermatogoides pteronyssinus (Der p). Materials and methodsBALB/c mice were intratracheally inoculated with Der p (50 μl, 1 mg/ml) once a week for 5 weeks. In addition, 30 min before Der p challenge, the mice were orally administered 1x DFSG (1 g/kg) or 1/2x DFSG (0.5 g/kg). Three days after the final challenge, the mice were sacrificed to evaluate inflammatory cell infiltration, lung histological features, blood total IgE, and cytokine levels in pulmonary alveolar lavage fluid. Furthermore, 30 min after the addition of DFSG, caffeic acid, p-coumaric acid or chlorogenic acid to A549 cells, 10 ng/ml IL-1β was added to evaluate the effect of the drug on mucin 5AC (MUC5AC) gene expression after stimulation of A549 cells by IL-1β. ResultsDFSG significantly reduced Der p-induced airway hyperresponsiveness, bronchial inflammatory cell infiltration, and total IgE and IgG1 serum levels. Furthermore, DFSG significantly inhibited TH2 cytokines and increased the expression of TH1 cytokines. In addition, immunohistochemical staining demonstrated that DFSG inhibited MUC5AC expression in the bronchial epithelial cells. DFSG and a mixture of caffeic acid, p-coumaric acid, and chlorogenic acid inhibited MUC5AC gene expression in A549 cells after stimulation with IL-1β. ConclusionThese results suggest that by regulating TH1 and TH2 cytokines and MUC5AC expression, DFSG exhibits anti-airway inflammatory cell infiltration and anti-hyperresponsiveness activity and inhibits specific immunity in a chronic asthmatic mouse model. Therefore, DFSG has potential for development into a drug for chronic asthma treatment.

Casticin inhibits interleukin-1β-induced ICAM-1 and MUC5AC expression by blocking NF-κB, PI3K-Akt, and MAPK signaling in human lung epithelial cells.

The compound casticin, isolated from Vitex rotundifolia, exerts anti-inflammatory effects and causes apoptosis of cancer cells. In this study, we explored the anti-inflammatory effects of casticin and modulation of cyclooxygenase (COX)-2, intercellular adhesion molecule 1 (ICAM-1), and mucin 5AC (MUC5AC) expression in interleukin-1β (IL-1β)–activated A549 human pulmonary epithelial cells. A549 cells were treated with various concentrations of casticin (5–20 μM), and an inflammatory response was triggered with interleukin (IL)-1β cytokines. Casticin decreased levels of IL-6, tumor necrosis factor α, and IL-8 and suppressed COX-2 expression and prostaglandin E2 production. It also reduced MUC5AC, proinflammatory cytokine, and chemokine gene expression and inhibited ICAM-1 expression for monocyte adhesion in IL-1β–stimulated A549 cells. In addition, casticin inhibited phosphorylation of Akt, phosphatidylinositol 3-kinase (PI3K), and mitogen-activated protein kinase (MAPK) and blocked nuclear transcription factor kappa-B (NF-κB) subunit p65 protein translocation into the nucleus. Co-culture of NF-κB, MAPK, and PI3K inhibitors with casticin also led to more significantly suppressed ICAM-1 expression in inflammatory A549 cells. These results provide evidence that casticin has an anti-inflammatory effect by blocking proinflammatory cytokine, chemokine, and ICAM-1 expression via suppression of the PI3K/Akt, NF-κB, and MAPK signaling pathways in IL-1β–stimulated inflammatory pulmonary epithelial cells.

The Flavonoid 7,4'-Dihydroxyflavone Inhibits MUC5AC Gene Expression, Production, and Secretion via Regulation of NF-κB, STAT6, and HDAC2.

Mucus overproduction is a significant component of the pathophysiology of obstructive lung diseases. Currently, there are only a few medications available that inhibit mucus production. Previous studies showed that glycyrrhizin, a triterpenoid in Glycyrrhiza uralensis inhibits mucin 5AC (MUC5AC) mRNA and protein expression. Other potential mucus production inhibitory compounds contained within in G. uralensis have not been fully investigated. The aim of the present study was to determine if the G. uralensis flavonoid 7,4'-dihydroxyflavone (7,4'-DHF) inhibits MUC5AC gene expression, mucus production, and secretion, and if so, to elucidate the mechanism of this inhibition. 7,4'-Dihydroxyflavone significantly decreased phorbol 12-myristate 13-acetate-stimulated NCI-H292 human airway epithelial cell MUC5AC gene expression and mucus production, at a 28-fold lower concentration than glycyrrhizin (The half maximal inhibitory concentration IC50 value of 1.4 μM vs 38 μM, respectively); 7,4'-DHF also inhibited MUC5AC mucus secretion. Inhibition was associated with the suppression of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), signal transducer and activator of transcription 6 (STAT6) activation, and enhanced histone deacetylase 2 (HDAC2) expression. In a murine model of asthma, 7,4'-DHF-treated mice exhibited a marked reduction in MUC5AC secretion in the bronchoalveolar lavage fluid compared with control mice. These findings, together with previous findings linking NF-κB, STAT6, and HDAC2 modulation to the control of MUC5AC expression, demonstrate that 7,4'-DHF is a newly identified component of G. uralensis that regulates MUC5AC expression and secretion via regulation of NF-κB, STAT6, and HDAC2.

Effects of ambient levels of traffic-derived air pollution on the ocular surface: Analysis of symptoms, conjunctival goblet cell count and mucin 5AC gene expression

PurposeTo quantify ocular symptoms, goblet cells (GC) and mucin 5AC (MUC5AC) gene expression on the conjunctiva of healthy subjects exposed to ambient levels of traffic-derived air pollution and to estimate its correlation with NO2 and particulate matter smaller than 2.5μm (PM2.5) levels. MethodsTwenty-one taxi drivers or traffic controllers were assessed with the Ocular Surface Disease Index (OSDI) questionnaire and conjunctival impression cytology. MUC5AC mRNA levels were determined based on the cytology of the right eye, and GC density was assessed based on the cytology of the left eye. Mean individual levels of 24-h NO2 and PM2.5 exposure were assessed the day before examination. Possible associations between NO2 or PM2.5 levels, OSDI scores, GC densities and MUC5AC mRNA levels were verified. ResultsThe subjects were exposed to mean PM2.5 levels of 35±12μg/m3 and mean NO2 levels of 189±47μg/m3. OSDI scores were low (7.4±8) and GC densities were 521±257 and 782±322 cell/mm2 on the bulbar and tarsal conjunctivas, respectively. The mean GC-derived MUC5AC mRNA expression was 14±7fM/μg of total RNA. A significant and positive correlation was observed between MUC5AC mRNA levels and tarsal GC density (p=0.018). A trend toward association between PM2.5 levels and tarsal GC cell density (p=0.052) was found. ConclusionExposure to ambient levels of air pollution impacts conjunctival GC density. An increase in MUC5AC mRNA levels may be part of an adaptive ocular surface response to long-term exposure to air pollution.

Abstract B61: Proteomic profiling of ovarian cancer and mesothelial cells reveals novel mediators implicated in the metastatic progression of ovarian cancer to the peritoneum

Abstract Over the past decade, numerous studies have highlighted the impact of the cancer microenvironment on tumor progression. It is now well understood that tumor cell behaviour is largely influenced by various stromal cell types and extracellular matrix components within their surrounding environments. A key hallmark of epithelial ovarian cancer (EOC) progression is the attachment of cancerous cells to the mesothelium and the formation of invasive peritoneal implants. Given that metastatic dissemination to the peritoneum is associated with poor prognosis, delineating the factors involved in cancer-peritoneal cell interaction, and the mechanisms they employ, is vital to improving patient survival as it may lead to the discovery of novel therapeutic targets. As such, we aimed to elucidate proteins that participate in this interaction by comparing the secreted proteome (referred to as the secretome) of an in vitro co-culture model containing ovarian cancer (OVCAR-5) and mesothelial cells (LP-9) to that of their monoculture secretomes. Using two-dimensional liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), we identified 1584 proteins that were secreted by co-cultures, and 1644 and 1420 proteins by OVCAR-5 and LP-9 cells, respectively. After comparative analysis and application of our filtering criteria, we identified 53 proteins that were differentially secreted during cancer and mesothelial interaction, and of these, mucin 5AC (MUC5AC) displayed significantly elevated secretion in the co-culture secretomes. Relative mRNA expression of candidates was assessed using quantitative PCR, which also revealed an increase in MUC5AC gene expression in three different co-culture models (OVCAR-5 and LP-9; BG-1 and LP-9; OV-90 and LP-9) (p&amp;lt;0.05). Immunocytochemistry analysis also revealed increased expression of MUC5AC in ovarian cancer and peritoneal co-cultures. Taken together, these findings reveal novel proteins that may potentially regulate the progression of ovarian cancer to the peritoneum, particularly MUC5AC, and elucidation of its role in EOC warrants further investigation. Citation Format: Natasha Musrap, George S. Karagiannis, Eleftherios P. Diamandis. Proteomic profiling of ovarian cancer and mesothelial cells reveals novel mediators implicated in the metastatic progression of ovarian cancer to the peritoneum. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: From Concept to Clinic; Sep 18-21, 2013; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2013;19(19 Suppl):Abstract nr B61.

Effect of β-lactoglobulin hydrolysate and β-lactorphin on intestinal mucin secretion and gene expression in human goblet cells

A hydrolysate obtained from a whey protein concentrate rich in β-lactoglobulin has been shown to stimulate mucin secretion and mucin 5AC gene expression in human intestinal goblet cells HT29-MTX. Mass spectrometry-based peptidomic analysis allowed the identification of the peptides contained in the hydrolysate. None of them had the required structure to bind opioid receptors, except for the sequence YLLF, corresponding to β-lactorphin. The exposure of the cells to synthetic β-lactorphin evoked a mucin secretory effect although no change in the mucin gene expression was observed. The amidated homolog of this peptide, which has been reported as a more potent opioid, induced mucin gene expression after incubation for 4h. This supports the hypothesis that induction of the mucin secretory response can be mediated by μ-opioid receptors in HT29-MTX cells, although other mechanisms responsible for the hydrolysate activity cannot be excluded. Protein hydrolysates with the ability to induce mucin secretion could be promising for improving gastrointestinal protection.

Suppression of prostaglandin E2-induced MUC5AC overproduction by RGS4 in the airway

The mechanism by which E-prostanoid (EP) receptor is critically involved in PGE(2)-induced mucin 5AC (MUC5AC) gene expression in the airway has been unclear. Furthermore, there have been little reports regarding the negative regulatory mechanism and/or proteins that affect PGE(2)-induced MUC5AC overproduction. In the present study, we found that PGE(2) induced MUC5AC gene expression in a dose-dependent manner (EC(50): 73.31 +/- 3.13 nM) and that the EP(2/4)-specific agonist, misoprostol, increased MUC5AC mRNA level, whereas the EP(1/3)-specific agonist, sulprostone, had no effect. Interestingly, the cAMP concentration (685.1 +/- 14.9 pM) of the EC(50) value of EP(4)-mediated cAMP production was much higher than that of EP(2) (462.33 +/- 23.79 pM), suggesting that EP(4) has higher sensitivity to PGE(2) compared with EP(2). Moreover, PGE(2)-induced Muc5ac overproduction was much increased in regulator of G protein signaling (Rgs) 4 knockout (KO) mice compared with wild-type mice at both transcriptional and translational levels, and it was dramatically suppressed in Rgs4 KO mice that had been infected with lentivirus expressing RGS4 (lenti::RGS4) compared with lentivirus expressing enhanced green fluorescent protein (lenti::eGFP). Finally, we demonstrate that PGE(2) can induce MUC5AC overproduction via the EP(4) receptor and that RGS4 may have suppressive effects in controlling MUC5AC overexpression in the airway. These findings may provide a molecular paradigm for the development of novel drugs for respiratory diseases.

Role of MUC5AC in the pathogenesis of exercise-induced bronchoconstriction

The pathogenesis of exercise-induced bronchoconstriction (EIB) involves the release of mediators from several airway cells in response to exercise challenge, but the mechanism leading to airflow obstruction during EIB is incompletely understood. To evaluate the role of secreted mucin in the pathogenesis of EIB. Induced sputum was collected at baseline and 30 minutes after exercise challenge in patients with asthma with EIB. The expression of gel-forming mucins and epidermal growth factor receptor ligands were assessed by quantitative polymerase chain reaction. Secreted mucin 5AC (MUC5AC), the eicosanoids cysteinyl leukotrienes (cysLTs) and 15S-hydroxyeicosatetraenoic acid (15S-HETE), and tachykinins neurokinin A (NKA) and substance P (SP) were measured in induced sputum supernatant. Among the gel-forming mucins, MUC5AC was expressed at the highest level. The gene expression of MUC5AC increased after exercise challenge compared with baseline and was associated with EIB severity by regression analysis. The relative levels of MUC5AC in induced sputum increased from a geometric mean of 9.5 at baseline to 18.4 postexercise challenge. Associations between the levels of MUC5AC and cysLTs and between the levels of cysLTs and NKA postexercise challenge were identified by regression analysis. These data indicate that (1) the predominant gel-forming mucin expressed in induced sputum of patients with asthma with EIB is MUC5AC; (2) an increase in MUC5AC gene expression and release of MUC5AC protein occurs after exercise challenge; and (3) MUC5AC release may occur through the cysLT-associated activation of sensory airway nerves.