Mucin Expression Research Articles

Effects of supplemental tannic acid on growth performance, gut health, microbiota, and fat accumulation and optimal dosages of tannic acid in broilers.

This study was conducted to investigate the effects of different dosages of tannic acid (TA) on growth performance, nutrient digestibility, gut health, immune system, oxidative status, microbial composition, volatile fatty acids (VFA), bone mineral density, and fat digestion and accumulation in broilers and to find optimal dosages of TA for efficient growth and gut health in broilers. A total of 320 male Cobb500 broilers were randomly distributed to 4 treatments with 8 replicates including 1) tannic acid 0 (TA0): basal diet without TA; 2) tannic acid 0.5 (TA0.5): basal diet with 0.5 g/kg TA; 3) tannic acid 1.5 (TA1.5); and 4) tannic acid 2.5 (TA2.5). Supplemental TA at levels greater than 972 mg/kg tended to reduce BW on D 21 (p = 0.05). The TA2.5 had significantly lower apparent ileal digestibility (AID) of crude protein compared to the TA0 group. The AID of ether extract tended to be reduced by TA at levels greater than 525 mg/kg (p = 0.08). The jejunal lipase activities tended to be reduced by TA at levels less than 595.3 mg/kg (p = 0.09). TA linearly decreased goblet cell density in the crypts of the jejunum (p < 0.05) and reduced mRNA expression of mucin two at levels less than 784.9 mg/kg and zonula occludens two at levels less than 892.6 mg/kg (p < 0.05). The TA0.5 group had higher activities of liver superoxide dismutase compared to the TA0 group (p < 0.05). Bone mineral density and contents tended to be linearly decreased by TA (p = 0.05), and the ratio of lean to fat was linearly decreased (p < 0.01). Total cecal VFA production tended to be linearly reduced by TA at levels greater than 850.9 mg/kg (p = 0.07). Supplemental TA tended to increase the relative abundance of the phylum Bacteroidetes (p = 0.1) and decrease the relative abundance of the phylum Proteobacteria (p = 0.1). The relative abundance of the family Rikenellaceae was the lowest at 500 mg/kg TA, and the relative abundance of the family Bacillaceae was the highest at 1,045 mg/kg TA. Collectively, these results indicate that the optimum level of supplemental TA would range between 500 and 900 mg/kg; this range of TA supplementation would improve gut health without negatively affecting growth performance in broilers under antibiotic-free conditions.

Mucin 1 aggravates synovitis and joint damage of rheumatoid arthritis by regulating inflammation and aggression of fibroblast-like synoviocytes.

AimsTo explore the synovial expression of mucin 1 (MUC1) and its role in rheumatoid arthritis (RA), as well as the possible downstream mechanisms.MethodsPatients with qualified synovium samples were recruited from a RA cohort. Synovium from patients diagnosed as non-inflammatory orthopaedic arthropathies was obtained as control. The expression and localization of MUC1 in synovium and fibroblast-like synoviocytes were assessed by immunohistochemistry and immunofluorescence. Small interfering RNA and MUC1 inhibitor GO-203 were adopted for inhibition of MUC1. Lysophosphatidic acid (LPA) was used as an activator of Rho-associated pathway. Expression of inflammatory cytokines, cell migration, and invasion were evaluated using quantitative real-time polymerase chain reaction (PCR) and Transwell chamber assay.ResultsA total of 63 RA patients and ten controls were included. Expression of MUC1 was observed in both the synovial lining and sublining layer. The percentage of MUC1+ cells in the lining layer of synovium was significantly higher in RA than that in control, and positively correlated to joint destruction scores of RA. Meanwhile, MUC1+ cells in the sublining layer were positively correlated to the Krenn subscore of inflammatory infiltration. Knockdown of MUC1, rather than GO-203 treatment, ameliorated the expression of proinflammatory cytokines, cell migration, and invasion of rheumatoid synoviocytes. Knockdown of MUC1 decreased expression of RhoA, Cdc42, and Rac1. Treatment with LPA compromised the inhibition of migration and invasion, but not inflammation, of synoviocytes by MUC1 knockdown.ConclusionUpregulated MUC1 promotes the aggression of rheumatoid synoviocytes via Rho guanosine triphosphatases (GTPases), thereby facilitating synovitis and joint destruction during the pathological process of RA.Cite this article: Bone Joint Res 2022;11(9):639–651.

Effects of Multi-Strain Probiotics and Perilla frutescens Seed Extract Supplementation Alone or Combined on Growth Performance, Antioxidant Indices, and Intestinal Health of Weaned Piglets.

Simple SummaryWeaning piglets face stressors from changes in feed and environment, which affects their growth. To resolve this problem, we explored the separate effects of multi-strain probiotics and Perilla frutescens seed extract and their combined effect on weaning piglets. We found multi-strain probiotics or Perilla frutescens seed extract both improved the gain to feed ratio and antioxidant capacity. In addition, multi-strain probiotics improved jejunal villus height and the villus height/crypt depth ratio. Perilla frutescens seed extract improved ileal villus height. The interactive effects were observed in jejunal villus height and the villus height/crypt depth ratio, ileal villus height, and the gene expression of IL-1β and mucin2 in the intestinal mucosa. This study shows that using either multi-strain probiotics or Perilla frutescens seed extract alone is more effective than their combined use in weaning piglets.This study examined the effects of multi-strain probiotics (BL) and Perilla frutescens seed extract (PSE), alone or in combination, on weaning piglets. In total, 96 weaning piglets were allocated into four treatments: CON group (the basal diet), PSE group (basal diet + 1g/kg PSE), BL group (basal diet + 2 g/kg BL), and BL+PSE group (basal diet +1 g/kg PSE + 2 g/kg BL) according to a 2 × 2 factorial arrangement. The supplementation of BL or PSE improved the gain to feed ratio. Dietary BL reduced diarrhea occurrence and Escherichia coli, but increased Lactobacillus counts in the ileal digesta. Dietary PSE tended to increase Lactobacillus counts in the ileal digesta. Interactive effects were found in terms of ileal villus height, the gene expression of IL-1β, and malondialdehyde in the ileal mucosa. Dietary BL lowered malondialdehyde in the spleen, liver, and jejunal mucosa but increased the total antioxidant capacity (T-AOC) in the liver and ileum mucosa. The supplementation of PSE improved superoxide dismutase in serum and T-AOC in the liver, and reduced MDA in liver, spleen, and jejunum mucosa. Taken together, BL or PSE showed positive effects, improving growth and intestinal morphology and enhancing antioxidant capacity. However, their interaction showed no beneficial effects on the antioxidant indices and the intestinal morphology of weaned piglets.

Involvement of IKK/IkBα/NF-kB p65 Signaling into the Regulative Effect of Engeletin on MUC5AC Mucin Gene Expression in Human Airway Epithelial Cells.

In this study, we examined whether engeletin exerts an effect on the gene expression of MUC5AC mucin, in human pulmonary epithelial NCI-H292 cells. The cells were pretreated with engeletin for 30 min and stimulated with phorbol 12-myristate 13-acetate (PMA), for the following 24 h. The effect of engeletin on PMA-induced nuclear factor kappa B (NF-kB) signaling pathway was also investigated. Engeletin suppressed the mRNA expression and production of MUC5AC mucin, induced by PMA through the inhibition of degradation of inhibitory kappa Bα (IkBα) and NF-kB p65 nuclear translocation. These results suggest engeletin inhibits the gene expression of mucin through regulation of NF-kB signaling pathway, in human airway epithelial cells.

Prognostic impact of MUC1 and potential regulatory miR-145 and miR-21 expression in salivary mucoepidermoid carcinoma.

Salivary gland mucoepidermoid carcinoma (MEC) poses a considerable risk of locoregional and distant metastasis after conventional treatments. There is an evident need for specifying prognostic biomarkers to identify patients who are in need of more intensive and prolonged follow-ups. This study aimed to assess the mucin 1 (MUC1) expression level and its potential regulatory microRNAs in salivary gland MEC and their prognostic potentials. The expression of MUC1 in salivary gland MEC tissues was assessed in 47 samples using immunohistochemistry. Related microRNA (miR-145 and miR-21) were evaluated using quantitative Reverse Transcription PCR. The associations between MUC1 and microRNAs expressions and clinicopathological parameters were investigated. MUC1 expression levels positively correlated with histologic grade (p < 0.001), clinical stage (p = 0.04), risk of nodal metastasis (p = 0.02), as well as the likelihood of opting for radical treatment (p = 0.01). Increased expression of miR-21 (p < 0.001) and decreased expression of miR-145 (p < 0.001) were observed in MECs compared to normal salivary gland tissue. MiR-145 negatively (p = 0.01) and miR-21 positively (p = 0.01) correlated with MUC1 overexpression. Based on the univariate cox proportional hazard model, histologic grade and MUC1 expression level were significantly associated with disease-free, cancer-specific, and overall survival. However, the multivariable cox proportional hazard model indicated tumor grade as the only prognostic factor associated with disease-free survival. Our results support the tumor suppressor role of miR-145 and the oncogenic role of miR-21 in salivary gland MEC. Also, MUC1 and miR-145 overexpression, as well as miR-21 suppression, show promising association with histologic tumor grade and clinical stage.

Si-Wu Water Extracts Protect against Colonic Mucus Barrier Damage by Regulating Muc2 Mucin Expression in Mice Fed a High-Fat Diet.

A high-fat diet (HFD) could cause gut barrier damage. The herbs in si-wu (SW) include dang gui (Angelica sinensis (Oliv.) Diels), shu di huang (the processed root of Rehmannia glutinosa Libosch.), chuan xiong (rhizome of Ligusticum chuanxiong Hort.), and bai shao (the root of Paeonia lactiflora f. pilosella (Nakai) Kitag.). Si-wu water extracts (SWE) have been used to treat blood deficiency. Components of one herb from SW have been reported to have anti-inflammatory and anti-obesity activities. However, there have been no reports about the effects of SWE on gut barrier damage. Therefore, the aim of the study was to explore the effect of SWE on gut barrier damage. In this study, we found that SWE effectively controlled body weight, liver weight, and feed efficiency, as well as decreased the serum TC level in HFD-fed mice. Moreover, SWE and rosiglitazone (Ros, positive control) increased the colonic alkaline phosphatase (ALP) level, down-regulated serum pro-inflammatory cytokine levels, and reduced intestinal permeability. In addition, SWE increased goblet cell numbers and mucus layer thickness to strengthen the mucus barrier. After supplementation with SWE and rosiglitazone, the protein expression of CHOP and GRP78 displayed a decrease, which improved the endoplasmic reticulum (ER) stress condition. Meanwhile, the increase in Cosmc and C1GALT1 improved the O-glycosylation process for correct protein folding. These results collectively demonstrated that SWE improved the mucus barrier, focusing on Muc2 mucin expression, in a prolonged high-fat diet, and provides evidence for the potential of SWE in the treatment of intestinal disease-associated mucus barrier damage.

Mucin expression in liver tumors

Difficulties in diagnosis, the prevalence of oncological processes, their medical, social and economic significance and high mortality rate determine the relevance of the fight against them and make the problem of studying the mechanisms of their early diagnosis one of the key ones. The subject of research now is the description of many biological markers, the determination of which allows us to assess the risks of developing a disease, diagnose a tumor, and serve as a biological indicator of the tumor process. The subjects of the study were tissue samples from 65 patients with liver cancer. The level of antibodies to MUC-1 and MUC-13 was studied. The established value of the concentration of antibodies to MUC-1 and MUC-13 in the blood serum of people with liver cancer is higher than the values in practically healthy individuals (p = 0.002; p = 0.0001), and the concentration of antibodies to MUC-1 and MUC-13 in the tissue tumors of cancer patients is higher than in the blood serum of healthy individuals and patients with liver cancer (p&lt;0.05). The expression level of MUC-1 and MUC-13 in the tumor tissue is not related to the age and sex of patients.

Dynamic Changes in Colonic Structure and Protein Expression Suggest Regulatory Mechanisms of Colonic Barrier Function in Torpor-Arousal Cycles of the Daurian Ground Squirrel.

Background: Both pathological conditions and hibernation can affect the barrier function of small intestine mucosa. However, the effect of hibernation on the barrier function of colonic mucosa remains unclear. Methods: We investigated morphological changes in colonic mucosa, the concentrations of specific proteins and molecules, and the enzymatic activity of diamine oxidase (DAO), in serum and colonic tissue; the expression of tight junction proteins and mucin, and the changes in inflammatory, farnesoid X receptor (FXR)–small heterodimer partner (SHP), and apoptosis-related molecules that could play a role in gut permeability changes in Daurian ground squirrels in summer active (SA), late torpor (LT), and interbout arousal (IBA) periods. Results: The results show that hibernation reduced the thickness of the colonic mucosa and the depth of the crypt, decreased the number of goblet cells (GCs), and damaged the structure of some microvilli. The concentrations of proteins and molecules, and the enzymatic activity of DAO, were all increased in the serum and colon, and the localization of tight junction proteins and mucin in the colonic mucosa were altered (compensatory response). Although the ground squirrels ate during the interbout arousal period, the changes remained similar to the response to torpor. Inflammation, apoptosis–anti-apoptosis, and FXR–SHP signaling may be involved in the possible changes in intestinal gut permeability during the torpor–arousal cycle in Daurian ground squirrels. In addition, periodic interbout arousal may play an inflammation-correcting role during the long hibernation season of Daurian ground squirrels.

Experimental study on effects of berberine combined with 6-shogaol on intestinal inflammation and flora in mice with ulcerative colitis

Cold-heat combination is a common method in the treatment of ulcerative colitis, which is represented by classic drug pair, Coptidis Rhizoma and Zingiberis Rhizoma.The present study explored the synergetic effects of berberine and 6-shogaol, the primary components of Coptidis Rhizoma and Zingiberis Rhizoma, respectively, on intestinal inflammation and intestinal flora in mice with ulcerative colitis to reveal the effect and mechanism of cold-heat combination in the treatment of ulcerative colitis.The ulcerative colitis model was induced by dextran sulfate sodium(DSS) in mice.The model mice were administered with berberine(100 mg·kg~(-1)), 6-shogaol(100 mg·kg~(-1)), and berberine(50 mg·kg~(-1)) combined 6-shogaol(50 mg·kg~(-1)) by gavage, once per day.After 20 days of drug administration, mouse serum, colon tissues, and feces were sampled.Hematoxylin-eosin(HE) staining was used to observe histopathological changes in colon tissues.Alcian blue/periodic acid-Schiff(AB/PAS) staining was used to observe the changes in the mucus layer of colon tissues.Enzyme-linked immunosorbent assay(ELISA) was employed to detect the serum content of tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), and interleukin-6(IL-6).Immunohistochemical method was adopted to detect the protein expression of macrophage surface markers F4/80, mucin-2, claudin-1, and zonula occludens-1(ZO-1) in colon tissues.High-throughput Meta-amplicon library sequencing was used to detect changes in the intestinal flora of mice.The results indicated that the 6-shogaol group, the berberine group, and the combination group showed significantly relieved intestinal injury, reduced number of F4/80-labeled positive macrophages in colon tissues, increased protein expression of mucin-2, claudin-1, and ZO-1, and decreased serum le-vels of TNF-α, IL-1β, and IL-6.Shannon, Simpson, Chao, and Ace indexes of the intestinal flora of mice in the 6-shogaol group and the combination group significantly increased, and Chao and Ace indexes in the berberine group significantly increased.As revealed by the bioinformatics analysis of intestinal flora sequencing, the relative abundance of Verrucomicrobia at the phylum, class, and order levels decreased significantly in all treatment groups after drug administration, while that of Bacillibacteria gradually increased.In the 6-shogaol group and the combination group, Akkermansia muciniphila completely disappeared, but acid-producing bacillus still existed in large quantities.As concluded, both 6-shogaol and berberine can inhibit intestinal inflammation, reduce the infiltration and activation of macrophages, relieve intestinal damage, reduce intestinal permeability, improve the structure of flora, and promote intestinal microecological balance.The combined application of berberine and 6-shogaol has a significant synergistic effect.

Understanding the mechanisms of gallbladder lesions: A systematic review.

The gallbladder undergoes different types of pathologies, ranging from inflammatory to preneoplasia and finally to malignant lesions. Gallbladder carcinoma can be highly invasive, and it is known that chronic inflammation of the gallbladder can lead to preneoplastic abnormalities and subsequently malignant phenotypes. Gallbladder neoplasia has a low incidence but is associated with a very poor prognosis. An early diagnosis is therefore extremely important in order to improve the prognosis of patients. Immunohistochemical markers of the mucin family can distinguish between different types of gallbladder lesions. Mucins are glycoproteins that can be attached to threonine residues that are O-glycosylated (due to the hydroxyl group of this amino acid). Mucins are divided into two types: those that bind to the membrane, such as MUC1, and those that form gels or are secreted, such as MUC5AC. Various alterations in mucin expression have been revealed to be associated with the development of neoplasia, as they modulate cell growth, karyokinetic transformation, dedifferentiation, adhesion, invasion and immune surveillance. p53 is a tumor suppressor gene and is linked to the development of different types of neoplasia. The incidence of the p53 gene is variable in the pathophysiology of gallbladder cancer. Several studies have revealed an incidence of ~50% of the p53 gene in gallbladder tumors. Studying the immunohistochemical profile of mucins and the presence of different gene mutations in neoplastic lesions of the gallbladder and surrounding mucosa may contribute to the understanding of the pathophysiology of the disease and the mechanisms involved in tumor development, allowing the identification of patients at increased risk of developing neoplasia, thus leading to improved management.

Chemoradiation-induced alteration of programmed death-ligand 1, CD8+ tumor-infiltrating lymphocytes and mucin expression in rectal cancer.

Introduction: DNA damage and resulting neoantigen formation is considered a mechanism for synergy between radiotherapy and PD-1/PD-L1 pathway inhibition to induce antitumor immune response. We investigated neoadjuvant chemoradiotherapy (nCRT)-induced changes in CD8+ tumor infiltrating lymphocyte, PD-L1 and mucin expression in rectal cancer patients.Materials and Methods: Tumor samples of rectal adenocarcinoma patients undergoing resection between 2008-2014 with (n = 62) or without (n = 17) nCRT treatment were collected. Sections were stained with CD8 and PD-L1 antibodies for immunohistochemistry. The prevalence of CD8+ cells was recorded in the tumor, interface tumor and background rectal side. Image analysis was used to determine the density of CD8+ lymphocytes. The percentage of PD-L1 expression was manually counted in tumor cells (TC), tumor stroma (TS) and the invasive front (IF). Mucin expression was determined as the percentage of the mucin area in the whole tumor area.Results: PD-L1 expression on TCs was identified in 7.6% (6/79) of nCRT specimens (p = 0.33) and in none of the non-nCRT patients. Median densities of CD8+ infiltrating T lymphocytes did not differ significantly between the two groups. Mucin expression was significantly higher in the nCRT cohort (p = 0.02). Higher neutrophil to lymphocytes ratio (NLR) after nCRT was associated with worse outcome (HR = 1.04, 95% CI = 1.00–1.08).Conclusions: nCRT exposure was associated with a non-significant difference in PD-L1 expression in rectal adenocarcinoma patients, possibly due to sample size limitations. Further mechanistic investigations and comprehensive immune analysis are needed to understand nCRT-induced immunologic shift in rectal cancer and to expand the applicability of checkpoint inhibitors in this setting.

Therapeutic effects of Hirudo medicinalis extract antigens on modulation of CD4+CD25+Foxp3 T cell activity in murine eimeriosis

Eimeriosis is a common parasitic disease in the chicken industry. The aim of this study was to assess the protective role of Hirudo extract antigens (HEA) against murine eimeriosis induced by Eimeria papillate. The oocyst output, developmental stages, goblet cells and oxidative stress, were investigated. Immunohistochemistry was used to detect anti-apoptotic Bcl2 marker and the number of both CD4+ and CD25+ cells in jejunal tissue, while ELISA was used to quantify TGF-β, IL-10 and IL-22 in jejunal tissue homogenate. Real-time PCR was also used to detect mRNA expression of mucin 2 (MUC2), inducible nitric oxide synthase (iNOS), IL-1β, IFN-γ, TNF-α, IL-6, and FoxP3. The most effective dose (5 µg/mice) reduced the oocyst output by 82.95 ± 1.02% (P ˂ 0.001). Similarly, the same dose reduced the jejunal developmental stages by 66.67 ± 0.49% (P ˂ 0.001). Furthermore, HEA therapy increased the number of jejunal goblet cells by 12.8 ± 1 (P ˂ 0.001) and the expression of MUC2 by 0.83 ± 0.06 (P ˂ 0.001). In contrast, TNF-α, IFN-γ, IL-6, iNOS, and IL-1β expression as well as apoptosis were reduced. The number of CD4+ and CD25+ in the jejunal tissue was increased (14.6 ± 1.2 (P ˂ 0.001), 6.84 ± 1 (P ˂ 0.01), respectively) after HEA therapy. The molecular analysis showed an increased expression of intestinal Foxp3 (3.2 ± 0.13 (P ˂ 0.001), while IL-22 was reduced (124 ± 10 (P ˂ 0.001)) versus an increase in TGF-β (250 ± 17 (P ˂ 0.01)) and IL-10 (236 ± 16 (P ˂ 0.001)) after HEA treatment in comparison to the non-treated infected group. With respect to the infected group, HEA reduced lipid peroxidation (LPO) (15.7 ± 1.12 (P ˂ 0.001)) and nitric oxide (NO) (13 ± 1.3 (P ˂ 0.001)) but increased reduced glutathione (GSH) (3.7 ± 0.26 (P ˂ 0.001)). In conclusion, HEA therapy protected against intestinal tissue damage by activation of CD4+CD25+Foxp3 cells which showed anti-inflammatory action. Hence, HEA can be recommended as a therapeutic treatment for eimeriosis.

Atypical Mucin Expression Predicts Worse Overall Survival in Resectable Pancreatic Ductal Adenocarcinoma.

Background Pancreatic ductal adenocarcinoma (PDAC) displays a typical mucin expression pattern which is characterized by MUC1 positive, MUC2 negative, and MUC5AC positive. More and more evidences show that mucins are involved in the development of pancreatic diseases. However, the relationship between mucin expression and prognosis of PDAC patients has been controversial in the past decades; therefore, we aim to figure out the association of mucin expression with survival in PDAC patients who underwent radical resection. Methods We performed immunohistochemistry (IHC) to detect the expression of MUC1, MUC2, and MUC5AC in resected PDAC specimens from Shanghai Cancer Center, Fudan University (FUSCC, n = 427) and obtained the corresponding clinical statistical data for retrospective study. Kaplan-Meier methods and Mantel-Cox tests were used to compare the survival curves, and the Cox regression model was employed for multivariate analyses to determine the independent risk factors. Survival analysis was also performed in the Queensland Centre for Medical Genomics (QCMG, n = 70) PDAC cohort to verify the conclusion. Results Both the FUSCC cohort and the QCMG cohort demonstrated that MUC1 absence was significantly correlated with worse overall survival (OS). The presence of MUC2 showed marginal significance in predicting shorter OS of PDAC patients, while MUC5AC had no prognostic value. In the FUSCC cohort, MUC1 absence was associated with increased proportion of stage III PDAC (p = 0.011), and MUC1 absence and MUC2 presence were associated with tumour perineural aggression (p = 0.011 and p = 0.030, respectively). Multivariable adjusted hazard ratios (HRs) for mortality of MUC1 and MUC2 were 0.492 (95% CI: 0.274-0.883, p = 0.017) and 1.596 (95% CI: 1.061-2.401, p = 0.025), respectively. Conclusions MUC1 absence or MUC2 presence is independently associated with poor OS among patients with resectable PDAC. MUC5AC absence tended to be associated with short-term death.

Citation: Tight Junction Protein Expression-Inducing Probiotics Alleviate TNBS-Induced Cognitive Impairment with Colitis in Mice.

A leaky gut is closely connected with systemic inflammation and psychiatric disorder. The rectal injection of 2,4,6-trinitrobenzenesulfonic acid (TNBS) induces gut inflammation and cognitive function in mice. Therefore, we selected Bifidobacterium longum NK219, Lactococcus lactis NK209, and Lactobacillus rhamnosus NK210, which induced claudin-1 expression in TNBS- or lipopolysaccharide (LPS)-stimulated Caco-2 cells, from the fecal bacteria collection of humans and investigated their effects on cognitive function and systemic inflammatory immune response in TNBS-treated mice. The intrarectal injection of TNBS increased cognitive impairment-like behaviors in the novel object recognition and Y-maze tests, TNF-α, IL-1β, and IL-17 expression in the hippocampus and colon, and LPS level in the blood and feces, while the expression of hippocampal claudin-5 and colonic claudin-1 decreased. Oral administration of NK209, NK210, and NK219 singly or together decreased TNBS-impaired cognitive behaviors, TNF-α and IL-1β expression, NF-κB+Iba1+ cell and LPS+Iba1+ cell numbers in the hippocampus, and LPS level in the blood and feces, whereas BDNF+NeuN+ cell and claudin-5+ cell numbers and IL-10 expression increased. Furthermore, they suppressed TNBS-induced colon shortening and colonic TNF-α and IL-1β expression, while colonic IL-10 expression and mucin protein-2+ cell and claudin-1+ cell numbers expression increased. Of these, NK219 most strongly alleviated cognitive impairment and colitis. They additively alleviated cognitive impairment with colitis. Based on these findings, NK209, NK210, NK219, and their combinations may alleviate cognitive impairment with systemic inflammation by suppressing the absorption of gut bacterial products including LPS into the blood through the suppression of gut bacterial LPS production and alleviation of a leaky gut by increasing gut tight junction proteins and mucin-2 expression.

Chitosan Oligosaccharide Attenuates Lipopolysaccharide-Induced Intestinal Barrier Dysfunction through Suppressing the Inflammatory Response and Oxidative Stress in Mice

This study was conducted to investigate the protective effect of chitosan oligosaccharide (COS) against lipopolysaccharide (LPS)-induced intestinal injury. The results demonstrated that COS improved the mucosal morphology of the jejunum and colon in LPS-challenged mice. COS alleviated the LPS-induced down-regulation of tight junction protein expressions and reduction of goblet cells number and mucin expression. The mRNA expressions of anti-microbial peptides secreted by the intestinal cells were also up-regulated by COS. Additionally, COS decreased pro-inflammatory cytokine production and neutrophil recruitment in the jejunum and colon of LPS-treated mice. COS ameliorated intestinal oxidative stress through up-regulating the mRNA expressions of nuclear factor E2-related factor 2 and downstream antioxidant enzymes genes. Correlation analysis indicated that the beneficial effects of COS on intestinal barrier function were associated with its anti-inflammatory activities and antioxidant capacity. Our study provides evidence for the application of COS to the prevention of intestinal barrier dysfunction caused by the stress of a LPS challenge.

Investigating the impacts of H2O2 treatment on gills of healthy Atlantic salmon reveals potential changes to mucus production with implications on immune activity

Current treatment strategies for relevant infectious diseases in Atlantic salmon (Salmo salar L.) include the use of low salinity or freshwater bathing. However, often availability is restricted, and hydrogen peroxide (H2O2) is used as an alternative. The potential impacts of H2O2 on fish mucosal tissues, especially the gills therefore need to be considered. In this study the mucosal and immunological effects of H2O2 treatment on the gills of healthy Atlantic salmon were examined by gene expression (qPCR) and immunohistochemistry (IHC) investigating T-cell, B-cell, and mucin activity. Healthy fish were treated with H2O2 and sampled at different times: 4 h, 24 h and 14 days post-H2O2 treatment (dpt) (total n = 18) to investigate the effect of holding time and H2O2 treatment. Treatment with H2O2 resulted in up-regulation of markers for T-cell activity and anti-inflammatory response and down-regulation of mucin expression in the gills at 14 dpt compared to fish sampled prior to treatment (0h; n = 5 fish). These findings were supported by IHC analysis, which despite being highly variable between samples, showed an increase in the number of CD3+ T cells at 14 dpt in 50% of treated fish compared to pre-treatment fish. The results from this study suggest that H2O2 treatment does not immune compromise healthy Atlantic salmon after 14 dpt (i.e., post-recovery) but modulates gill immune activity and disrupts the mucus covering of the gills. However, further studies are required to determine whether the effects observed are related to H2O2 treatment in isolation or other variables such as holding time or environmental factors.

Investigating the Role of the NLRP3 Inflammasome Pathway in Acute Intestinal Inflammation: Use of THP-1 Knockout Cell Lines in an Advanced Triple Culture Model.

The NLRP3 inflammasome plays an important role in intestinal homeostasis as well as inflammation. However, in vivo studies investigating the role of the NLRP3 inflammasome in inflammatory bowel disease (IBD) report contrasting results, leaving it unclear if the NLRP3 inflammasome augments or attenuates intestinal inflammation. To investigate the role of the NLRP3/caspase-1 pathway in a model of acute intestinal inflammation, we modified a previously established in vitro triple culture model of the healthy and inflamed intestine (Caco-2/HT29-MTX-E12/THP-1). Using THP-1 knockout cell lines, we analyzed how the NLRP3 inflammasome and its downstream enzyme caspase-1 (CASP1) affect inflammatory parameters including barrier integrity and cytotoxicity, as well as gene expression and secretion of pro-inflammatory cytokines and mucus. Furthermore, we investigated differences in inflammation-mediated cytotoxicity towards enterocyte-like (Caco-2) or goblet-like (HT29-MTX-E12) epithelial cells. As a complementary approach, inflammation-related cytotoxicity and gene expression of cytokines was analyzed in intestinal tissue explants from wildtype (WT) and Nlrp3-/- mice. Induction of intestinal inflammation impaired the barrier, caused cytotoxicity, and altered gene expression of pro-inflammatory cytokines and mucins in vitro, while the knockout of NLRP3 and CASP1 in THP 1 cells led to attenuation of these inflammatory parameters. The knockout of CASP1 tended to show a slightly stronger attenuating effect compared to the NLRP3 knockout model. We also found that the inflammation-mediated death of goblet-like cells is NLRP3/caspase-1 dependent. Furthermore, inflammation-related cytotoxicity and upregulation of pro-inflammatory cytokines was present in ileal tissue explants from WT, but not Nlrp3-/- mice. The here presented observations indicate a pro-inflammatory and adverse role of the NLRP3 inflammasome in macrophages during acute intestinal inflammation.

Oregano Essential Oils Mediated Intestinal Microbiota and Metabolites and Improved Growth Performance and Intestinal Barrier Function in Sheep.

With the increased demand for safe and sustainable alternatives to growth promoting antibiotics in the livestock industry, oregano essential oils (OEO) and Lactobacillus reuteri (LR) have been examined as alternatives to antibiotics for growth promotion and to improve animal health and performance. However, the mechanism underlying the OEO and LR mediation of sheep growth remains unknown. In this study, 16S rRNA gene sequencing and untargeted metabolomics were used to determine the role of the gut microbiota in the growth improvements observed. The potential modulating roles of intestinal microbial metabolites of OEO and LR to intestinal health were systematically explored as well. It was observed that both OEO and LR had greater average daily gain (ADG) and lower F/G ratio. Furthermore, OEO also appeared to have produced a greater amylase enzyme activity and mucin gene expression in the jejunal mucosa. It was also observed that OEO reduced serum IL-2 and TNF-β as well as mRNA levels of NF-κB p65, toll-like receptor-4 (TLR-4), and IL-6 in the jejunal mucosa. Moreover, dietary OEO supplementation increased the abundances of Ruminococcus, Bifidobacterium and Enterococcus, while the relative abundances of Succiniclasticum, Marvinbryantia and Streptococcus were enriched in LR group. Spearman’s correlation analysis revealed that the abundances of Bifidobacterium, Ruminococcus and Enterococcus were positively correlated with the mRNA expression of mucins. Moreover, the relative abundance of Enterococcus was positively correlated with amylase activity. Metabolomics analysis indicated that OEO and LR increased the levels of indole acetaldehyde and indole-3-acetic acid through the tryptophan metabolism pathway. It was observed that LR also decreased the inflammatory metabolites including tryptamine and 5-hydroxyindole-3-acetic acid. Collectively, these results suggested that OEO exerted a beneficial effect on growth performance and the mucosal barrier, affected tryptophan metabolism and improved the intestinal microbiota of sheep.

Prevalence and Mechanisms of Mucus Accumulation in COVID-19 Lung Disease.

Rationale: The incidence and sites of mucus accumulation and molecular regulation of mucin gene expression in coronavirus (COVID-19) lung disease have not been reported. Objectives: To characterize the incidence of mucus accumulation and the mechanisms mediating mucin hypersecretion in COVID-19 lung disease. Methods: Airway mucus and mucins were evaluated in COVID-19 autopsy lungs by Alcian blue and periodic acid-Schiff staining, immunohistochemical staining, RNA in situ hybridization, and spatial transcriptional profiling. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected human bronchial epithelial (HBE) cultures were used to investigate mechanisms of SARS-CoV-2-induced mucin expression and synthesis and test candidate countermeasures. Measurements and Main Results: MUC5B and variably MUC5AC RNA concentrations were increased throughout all airway regions of COVID-19 autopsy lungs, notably in the subacute/chronic disease phase after SARS-CoV-2 clearance. In the distal lung, MUC5B-dominated mucus plugging was observed in 90% of subjects with COVID-19 in both morphologically identified bronchioles and microcysts, and MUC5B accumulated in damaged alveolar spaces. SARS-CoV-2-infected HBE cultures exhibited peak titers 3 days after inoculation, whereas induction of MUC5B/MUC5AC peaked 7-14 days after inoculation. SARS-CoV-2 infection of HBE cultures induced expression of epidermal growth factor receptor (EGFR) ligands and inflammatory cytokines (e.g., IL-1α/β) associated with mucin gene regulation. Inhibiting EGFR/IL-1R pathways or administration of dexamethasone reduced SARS-CoV-2-induced mucin expression. Conclusions: SARS-CoV-2 infection is associated with a high prevalence of distal airspace mucus accumulation and increased MUC5B expression in COVID-19 autopsy lungs. HBE culture studies identified roles for EGFR and IL-1R signaling in mucin gene regulation after SARS-CoV-2 infection. These data suggest that time-sensitive mucolytic agents, specific pathway inhibitors, or corticosteroid administration may be therapeutic for COVID-19 lung disease.

Selenium Nanoparticles Improved Intestinal Health Through Modulation of the NLRP3 Signaling Pathway.

Selenium nanoparticles (SeNPs) play important roles in promoting animal health, however, their impact on intestinal health remains elusive. This study was intended to evaluate the effects of different doses of SeNPs on the intestinal health, especially the development of goblet cells in the broiler jejunum. A total of 480 1-day-old Arbor Acres broilers were randomly allotted to 5 treatments with 6 replications of 16 chicks each. Birds were fed with low selenium corn-soybean meal-based diets supplemented with 0.1, 0.2, 0.3, or 0.4 mg/kg of SeNPs. On d 21, dietary supplementation of SeNPs effectively reduced the mortality of broilers. The villus height and the villus height/crypt depth ratio of the jejunum showed significant quadratic effects with the increasing concentration of SeNPs (P < 0.05). The mRNA expression of zonula occluden-1 (ZO-1), ZO-2, claudin-3, and claudin-5 in the jejunum decreased linearly with the increasing dose of SeNPs (P < 0.05). The mRNA expression levels of interleukin 1 beta (IL-1β), IL-18, and the concentration of reactive oxygen species (ROS) in the jejunum decreased linearly with the increase of SeNPs concentration (P < 0.05). Compared with the control group, the number of goblet cells in the jejunum was significantly increased by adding 0.1 and 0.4 mg/kg SeNPs(P < 0.05). In addition, the mRNA expression of Mucin2 (Muc2) showed a significant quadratic relationship that increased after adding 0.1 mg/kg SeNPs (P < 0.05). Dietary SeNPs also linearly reduced the expression of v-myc avian myelocytomatosis viral oncogene homolog (c-myc) (P < 0.05). The mean density of TUNEL positive cells in the 0.2 and 0.4 mg/kg SeNPs groups were lower than the control group (P < 0.05). Similarly, the mRNA expression levels of B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X (Bax), NLR family pyrin domain containing 3 (NLRP3), cysteinyl aspartate specific proteinase-1 (Caspase-1), toll-like receptor-2 (TLR-2), and myeloid differentiation factor 88 (MyD88) in the jejunum decreased linearly with the increase of SeNPs concentration (P < 0.05). Results show that supplementation with 0.2 mg/kg SeNPs may decrease intestinal oxidative stress and inflammation by modifying the activation of NLRP3 signaling pathway, which can effectively promote intestinal goblet cells of 21-day-old broilers.