Goblet Cell Proliferation Research Articles

Quercetin Alleviates Asthma-Induced Airway Inflammation and Remodeling through Downregulating Periostin via Blocking TGF‐β1/Smad Pathway

Introduction: The aim of the study was to discuss whether the anti-asthmatic effect of quercetin is related to periostin and the downstream molecular pathway of quercetin’s anti-asthmatic effect. Methods: We constructed asthmatic mice, sensitized by ovalbumin, and administrated different treatments into mice according to the experimental design. In this study, we mainly observed the inflammatory response, airway fibrosis, and airway hyperresponsiveness in asthmatic mice. Pathological stains (H&E, PAS, and Masson) were performed. We also detected the inflammation factors and fibrosis-related cytokines by enzyme-linked immunosorbent serologic assay. In addition, we also explored the level of periostin by enzyme-linked immunosorbent serologic assay and Western blot. At the same time, TGF‐β1/Smad pathway was also determined by Western blot. Results: A high expression of periostin was found in asthmatic mice, and quercetin decreases periostin content in bronchoalveolar lavage fluid. Quercetin and OC-20 inhibit airway inflammation response, airway fibrosis, and airway hyperreactivity. Quercetin downregulated TGF‐β1/Smad pathway in the lung tissues of asthmatic mice. Anti-asthma role of quercetin is related to periostin. Then deeper mechanical study revealed that inhibiting TGF-β1 could improve asthmatic symptoms, and quercetin exerted the protective effect on asthmatic mice through inhibition of TGF‐β1/Smad pathway. Conclusion: Quercetin provided a protective role against asthma via periostin, manifested by mild inflammatory infiltration, reduced goblet cell proliferation, and reduced airway fibrosis. TGF‐β1/Smad pathway is an important transduction system, participating in the protective effect of quercetin on asthma.

Dietary iron regulates intestinal goblet cell function and alleviates Salmonella typhimurium invasion in mice.

Iron is an important micronutrient that plays a vital role in host defenses and bacterial pathogenicity. As iron treatments increase the risk of infection by stimulating the growth and virulence of bacterial pathogens, their roles in anti-infection immunity have frequently been underestimated. To estimate whether adequate dietary iron intake would help defend against pathogenic bacterial infection, mice were fed iron-deficient (2 mg kg-1 feed), iron-sufficient (35 mg kg-1 feed), or iron-enriched diet (350 mg kg-1 feed) for 12 weeks, followed by oral infection with Salmonella typhimurium. Our results revealed that dietary iron intake improved mucus layer function and decelerated the invasion of the pathogenic bacteria, Salmonella typhimurium. Positive correlations between serum iron and the number of goblet cells and mucin2 were found in response to total iron intake in mice. Unabsorbed iron in the intestinal tract affected the gut microbiota composition, and the abundance of Bacteroidales, family Muribaculaceae, was positively correlated with their mucin2 expression. However, the results from antibiotic-treated mice showed that the dietary iron-regulated mucin layer function was not microbial-dependent. Furthermore, in vitro studies revealed that ferric citrate directly induced mucin2 expression and promoted the proliferation of goblet cells in both ileal and colonic organoids. Thus, dietary iron intake improves serum iron levels, regulates goblet cell regeneration and mucin layer function, and plays a positive role in the prevention of pathogenic bacteria.

Histopathological Changes Caused by Parasites in Carangoides Bajad Fish in the Red Sea, Jeddah

This research focused on discovering parasites in the fish Carangoides bajad (orange-spotted trevally) (Forsskal, 1775) that were captured from the Red Sea off Saudi Arabia. Carangoides bajad (n = 120) were collected during the spring and summer of 2019. Internal parasites were extracted and subjected to parasitological analyses and fish intestines were subjected to histopathological analyses. The average length and weight of Carangoides bajad were 39.88 ± 8.7 cm and 1.68 ± 0.58 kg, respectively. We identified Anisakis (17.5%), Lecithocladium (23.33%), and Bucephalus spp (29.17%) in the infected fish. Female fish outnumbered males, suggesting that sex significantly influence the prevalence of parasitic infections. Parasites, or evidence of parasitic infection, were not detected in small fish (weighing 0.5–0.90 kg or 1.0–1.49 kg, and 20.0–29.9-cm long). Similarly, the values of Fulton’s condition factor (K) ranged between 3.0–3.99 and 4.0–4.99, supporting the conclusion that these small fish were not infected with parasites. The data on larger fish (weighing 1.5–1.90 kg or 2.0–2.49 kg or 2.5–2.99 kg and length 20.0–29.9 cm or 30.0–39.9 cm or 40.0–49.9 cm or 50.0–59.9 cm) reveal that parasitic infections significantly influenced the length, weight, and Fulton’s condition factor (K) according to the prevalence and intensity of infection of Carangoides bajad. Histopathological examination revealed intestinal tissue damage; and 45% of inflamed tissues involved swelling of the intestinal villi. Further, we observed separation of the mucosal epithelia from the submucosa, proliferation of goblet cells, and lymphocyte infiltration accompanied by atrophy and lysis of intestinal villi. The present study demonstrates infection of Carangoides bajad with three types of parasites and documents their deleterious effects.

Rosmarinic Acid Restores Colonic Mucus Secretion in Colitis Mice by Regulating Gut Microbiota-Derived Metabolites and the Activation of Inflammasomes.

Maintaining a steady state of mucus barrier is an important potential target for polyphenol to exert its anticolitis activity. This study elucidates the pivotal role of polyphenol rosmaric acid (RA) in regulating the mucus barrier function and alleviating inflammation by identifying its gut microbiota-derived metabolites and evaluating its inhibitory effect on inflammasomes in colitis mice. Results demonstrated that RA treatment promoted the proliferation of goblet cells and restored the level of mucus secretion, especially Muc2. RA reshaped the microbiota of colitis mice, particularly the boost of core probiotics, such as p. Bacteroidaceae, f. Muribaculaceae, g. Muribaculaceae, g. Alistipes, and g. Clostridia_UCG-014. Nontargeted metabonomics and targeted metabonomics confirmed a significant increase in the bile acids and their metabolites (7-sulfocholic acid, stercobilin, chenodeoxycholic acid 3-sulfate, chenodeoxycholic acid sulfate, and ursodeoxycholic acid 3-sulfate), indole metabolites ((R)-2,3-dihydro-3,5-dihydroxy-2-oxo-3-indoleacetic acid, frovatriptan, 3-formyl-6-hydroxyindole, and brassicanal A), and short-chain fatty acids (SCFAs) (acetic acid, butyric acid, isobutyric acid, isovaleric acid, and valeric acid) that contributed to the strengthened mucus barrier function. In addition, being absorbed mainly in the lower digestive tract, RA inhibited the overexpression of inflammasomes (especially NLRP6) that occurred in colitis mice to promote the mucus secretion of goblet cells. These data confirmed that RA, as a promising candidate to enhance gut health, restored colonic mucus secretion in colitis mice by mediating the production of gut microbiota-derived metabolites and the overexpression of inflammasomes. The presented study provides scientific evidence explaining the apparent paradox of low bioavailability and high bioactivity in polyphenols.

Changes in percentage of GATA3+ regulatory T cells and their pathogenic roles in allergic rhinitis

To investigate the changes in percentage of GATA3+ regulatory T (Treg) cells in patients with allergic rhinitis (AR) and mouse models. The nasal mucosa specimens were obtained from 6 AR patients and 6 control patients for detection of nasal mucosal inflammation. Peripheral blood mononuclear cells (PBMC) were collected from 12 AP patients and 12 control patients to determine the percentages of Treg cells and GATA3+ Treg cells. In a C57BL/6 mouse model of AR, the AR symptom score, peripheral blood OVA-sIgE level, and nasal mucosal inflammation were assessed, and the spleen of mice was collected for detecting the percentages of Treg cells and GATA3+ Treg cells and the expressions of Th2 cytokines. Compared with the control patients, AR patients showed significantly increased eosinophil infiltration and goblet cell proliferation in the nasal mucosa (P < 0.01) and decreased percentages of Treg cells and GATA3+ Treg cells (P < 0.05). The mouse models of AR also had more obvious allergic symptoms, significantly increased OVA-sIgE level in peripheral blood, eosinophil infiltration and goblet cell hyperplasia (P < 0.01), markedly lowered percentages of Treg cells and GATA3+ Treg cells in the spleen (P < 0.01), and increased expressions of IL-4, IL-6 and IL-10 (P < 0.05). The percentage of GATA3+ Treg cells is decreased in AR patients and mouse models. GATA3+ Treg cells possibly participate in Th2 cell immune response, both of which are involved in the occurrence and progression of AR, suggesting the potential of GATA3+ Treg cells as a new therapeutic target for AR.

Interaction of high temperature and NO2 exposure on asthma risk: In vivo experimental evidence of inflammation and oxidative stress

Allergic asthma is a complicated respiratory disease with many concerns. Mounting epidemiological evidence linked temperature (T) and NO2 with allergic asthma, yet toxicological studies remain scarce. We conducted an in vivo study to explore toxicological evidence in T-NO2 interaction on allergic asthma, to investigate underlying toxicological mechanisms. 90 male Balb/c mice were randomly and equally divided into 6 groups including saline control, ovalbumin (OVA)-sensitized, OVA + 35 °C, OVA + NO2, OVA + 35 °C + NO2, and OVA + 35 °C + NO2 + capsazepine (CZP), adopting treatment for 38 days. We measured pulmonary functions of inspiratory resistance (Ri), expiratory resistance (Re) and airway compliance (Cldyn), serum protein biomarkers, indexes of pulmonary inflammation, histopathological changes and protective effects of CZP. Airway hyperresponsiveness (AHR) was aggravated by high T (35 °C) and NO2 (5 ppm) co-exposure with a series of aggravating asthmatic symptoms including airway wall thickening, lumen stenosis, goblet cell proliferation, mucus hypersecretion, and subepithelial fibrotic hyperplasia, providing evidence in the toxicological impact of high T-NO2 interaction. The biomarkers of serum immune functions (Total-IgE, OVA-sIgE and IL-4), pro-inflammation (IL-6 and TNF-α), oxidative stress cytokines (8-OHdG, ROS and MDA), airway resistance (Ri and Re), and TRPV1 expression significantly increased, while IFN-γ, GSH and airway compliance (Cldyn) significantly decreased with co-exposure to high T and NO2. We observed that CZP addition significantly ameliorated these toxicological effects and biomarker levels induced by heat-NO2 interaction. Our results suggest a toxicity of heat-NO2 interaction on asthma with clear mechanisms, which can be ameliorated by CZP, indicating that both oxidative stress and TRPV1 expression may be primarily responsible for asthma of heat-NO2-induced toxicity.

Immuno-modulatory Effects of Inactivated Dietzia Maris on the Selected Aspects of Cellular and Humoral Immune Responses in Mice.

The current study is an attempt to register the alterations in the immunological and histological parameters in mice arising from the administration of Dietza maris (D. maris) in order to confirm its protective properties. Mice underwent 7 days of treatment with three doses of D. maris. Then, animals were scrutinized in terms of body weight, relative weight of organs, delayed type of hypersensitivity (DTH) response, and hemagglutination titer (HT). The determination of villus height, villus width, crypt depth, villus/crypt ratio (V/C), Goblet cells, and intestinal epithelial lymphocyte (IEL) density in villi was carried out. A boosted DTH response was observed as a result of bacteria at medium dose. A variation was noted between the hemagglutinin titer of the control group and that of the high-dose group. Crypt depth, villus width, and villus height manifested alterations. High-dose-treated mice demonstrated proliferation of Goblet cells in the villi, whereas both in medium- and high-dose-treated mice, a distribution of IELs in the villus epithelium was noted. Overall, D. maris showed a stimulatory effect on immune functions in mice. Thus, thanks to improved cellular and humoral immunity and the increased quality of intestine function, we believe that D. maris promises novel therapeutic applications in the future. The attained findings lend credence to immuno-stimulatory effects arising from the capacity of D. maris to function as immunological adjuvants and to enhance humoral and cellular immunity as well as the intestinal structure and function.

Systematic Pharmacology-Based Strategy to Explore the Mechanism of Bufei Huoxue Capsule in the Treatment of Chronic Obstructive Pulmonary Disease.

To explore the effects and mechanisms of Bufei Huoxue Capsule (BHC) on chronic obstructive pulmonary disease (COPD) based on network pharmacology. The effective components and related targets of BHC were collected by searching TCMSP, HERB, and ETCM databases, after which the related targets of COPD were obtained on GeneCards and OMIM databases. The common targets were imported into the STRING database and Cytoscape database to construct a target interaction network and screen core targets. Next, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed on the Metascape platform. According to the prediction results of network pharmacology, the action mechanism was further examined in an animal model of COPD. The pathological changes of lung tissue were observed by HE staining; goblet cells and mucus secretion in lung tissue were observed by AB-PAS staining, airway collagen deposition was observed by Masson staining, and the expression of NE, TGF-β1, P-EGFR/EGFR, P-ERK1/2/ERK1/2, P-JNK/JNK, and P-P38/P38MAPK protein was detected by Western blot analysis. A total of 379 targets related to BHC and 7391 targets related to COPD were obtained, including 313 potential targets of BHC in treating chronic obstructive pulmonary disease, with JUN, AKT1, TNF, IL6, EGFR, MAPK1, and MAPK14 as the core targets. Through enrichment analysis, BHC may interfere with COPD by regulating the MAPK signal pathway, HIF-1 signal pathway, NF-κB signal pathway, cAMP signal pathway, cGMP-PKG signal pathway, and so on. Animal experiments showed that the BHC could reduce airway inflammatory cell infiltration, inhibit airway epithelial goblet cell proliferation, reduce mucus secretion, and improve small airway collagen fiber deposition in COPD model rats. Besides, BHC could downregulate the protein expression of NE, TGF-β1, P-EGFR, P-ERK1/2, and P-P38MAPK. BHC can reduce airway inflammation, inhibit mucus hypersecretion, and improve airway remodeling by regulating the MAPK signal transduction pathway.

Black corn (Zea mays L.) flour has the potential to improve the gut microbiota composition and goblet cell proliferation in mice fed a high-fat diet

High-fat diets are associated with intestinal dysbiosis and leaky gut leading to intestinal inflammation. Bioactive components, including phenolic compounds, isolated or in their original food matrix, have alleviated intestinal impairments promoted by a high-fat diet. Black corn (Zea mays L.) is a colored corn in which anthocyanins are the most abundant bioactive compound. Thus, we hypothesized that black corn flour may have preventive effects on poor intestinal health in mice fed a high-fat diet. To study this, 30 C57BL/6 mice were randomly divided into 3 experimental groups receiving the following diets for 8 weeks: normal control (fed a normal diet); high-fat (fed a high-fat diet: 60% of calories from fat); high-fat corn (fed a high-fat diet added with 20% of black corn whole flour). The cecal microbiota analyzed by 16S ribosomal RNA sequencing showed that black corn flour intake increased the relative abundance of Ruminococcus, Roseburia, and Prevotellaceae_UCG-001, and decreased Bacteroides and Faecalibaculum. No difference was observed in the cecal short-chain fatty acids and fecal pH among the experimental groups (P > .05). Further, the consumption of black corn flour improved cecal morphology by increasing the number of goblet cells but with no difference in the crypt depth and width. These findings suggest that black corn flour as a source of anthocyanins could have preventive effects on gut dysbiosis resulting from a high-fat diet. SCFA, short chain fatty acids.

Dietary Antimicrobial Peptides Improve Intestinal Function, Microbial Composition and Oxidative Stress Induced by Aeromonas hydrophila in Pengze Crucian Carp (Carassius auratus var. Pengze).

There is increasing evidence for the potential use of antimicrobial peptides as dietary supplements and antibiotic substitutes. In this study, we analyzed the differential effects of varying levels of antimicrobial peptides on the intestinal function and intestinal microbial and disease resistance of Pengze crucian carp. Approximately 630 experimental fishes were randomized in the control group (G0: 0 mg/kg) and in five groups supplemented with different doses of AMPs (G1: 100 mg/kg, G2: 200 mg/kg, G3: 400 mg/kg, G4: 800 mg/kg, and G5: 1600 mg/kg) and were fed for ten weeks. Three replicates per group of 35 fish were performed. The results showed that AMPs promoted intestinal villus development and increased intestinal muscular thickness (p < 0.05) and goblet cell abundance. The enzymatic activities of all groups supplemented with AMPs were effectively improved. AMP supplementation significantly enhanced the activities of antioxidant enzymes and digestive enzymes in the intestines of G3 animals (p < 0.05). Compared with G0 animals, AMP-supplemented animals regulated the expression of intestinal immune-related genes and exhibited significant differences in the G3 animal group (p < 0.05). The abundance of intestinal Firmicutes and Bacteroidetes increased in the AMP-supplemented groups, but the Firmicutes/Bacteroidetes ratio was lower than that in the G0 group. AMP supplementation also decreased the abundance of Fusobacterium while increasing the proportion of Actinobacteria (p < 0.05). After Aeromonas hydrophila infection, the expression levels of anti-inflammatory factors in the intestinal tract of G3 animals were significantly upregulated, and the level of the proinflammatory factor was decreased (p < 0.05). The intestinal Cetobacterium levels of G3 animals were significantly increased (p < 0.01), while the Proteobacteria levels were decreased, and the intestinal goblet cell proliferation was significantly lower than that of G0 animals (p < 0.05). This indicates that groups supplemented with AMPs have better disease resistance than the G0 group and can rapidly reduce the adverse effects caused by inflammatory response. Taken together, the present results suggest that AMP supplementation can improve intestinal function and intestinal microbial and pathogen resistance in Pengze crucian carp.

Mechanism of "Ephedrae Herba-Descurainiae Semen Lepidii Semen" combination in treatment of bronchial asthma based on network pharmacology and experimental verification

This study aims to investigate mechanism of &quot;Ephedrae Herba-Descurainiae Semen Lepidii Semen&quot; combination(MT) in the treatment of bronchial asthma based on network pharmacology and in vivo experiment, which is expected to lay a theoretical basis for clinical application of the combination. First, the potential targets of MT in the treatment of bronchial asthma were predicted based on network pharmacology, and the &quot;Chinese medicine-active component-target-pathway-disease&quot; network was constructed, followed by Gene Oncology(GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment of the potential targets. Molecular docking was used to determine the binding activity of key candidate active components to hub genes. Ovalbumin(OVA, intraperitoneal injection for sensitization and nebulization for excitation) was used to induce bronchial asthma in rats. Rats were classified into control group(CON), model group(M), dexamethasone group(DEX, 0.075 mg·kg~(-1)), and MT(1∶1.5) group. Hematoxylin and eosin(HE), Masson, and periodic acid-Schiff(PAS) staining were performed to observe the effect of MT on pathological changes of lungs and trachea and goblet cell proliferation in asthma rats. The levels of transforming growth factor(TGF)-β1, interleukin(IL)6, and IL10 in rat serum were detected by enzyme-linked immunosorbent assay(ELISA), and the mRNA and protein levels of mitogen-activated protein kinase 8(MAPK8), cyclin D1(CCND1), IL6, epidermal growth factor receptor(EGFR), phosphatidylinositol 3-kinase(PI3 K), and protein kinase B(Akt) by qRT-PCR and Western blot. Network pharmacology predicted that MAPK8, CCND1, IL6, and EGFR were the potential targets of MT in the treatment of asthma, which may be related to PI3 K/Akt signaling pathway. Quercetin and β-sitosterol in MT acted on a lot of targets related to asthma, and molecular docking results showed that quercetin and β-sitosterol had strong binding activity to MAPK, PI3 K, and Akt. In vivo experiment showed that MT could effectively alleviate the symptoms of OVA-induced asthma rats, improve the pathological changes of lung tissue, reduce the production of goblet cells, inhibit the inflammatory response of asthma rats, suppress the expression of MAPK8, CCND1, IL6, and EGFR, and regulate the PI3 K/Akt signaling pathway. Therefore, MT may relieve the symptoms and inhibit inflammation of asthma rats by regulating the PI3 K/Akt signaling pathway, and quercetin and β-sitosterol are the candidate active components.

Lactobacillus derived from breast milk facilitates intestinal development in IUGR rats.

The intestinal microbiota contributes to infant's intestine homeostasis. This study aimed to analyse how probiotics derived from breast milk promote infant intestinal development in rat pups. The effect of potential probiotics derived from breast milk on development of intrauterine growth retardation (IUGR) newborn rats' intestine was investigated. Limosilactobacillus oris ML-329 and Lacticaseibacillus paracasei ML-446 exhibited good hydrophobicity percentages (p < 0.05). ML-446 showed a significant effect on intestinal length and weight (p < 0.05). Meanwhile, the villus height of the IUGR newborn rats fed with ML-329 was significantly higher compared with those fed with Lacticaseibacillus rhamnosus GG (p < 0.05). Moreover, ML-329 and ML-446 both significantly stimulated the proliferation and differentiation of intestinal epithelial cells by increasing the number of ki67-positive cells, goblet cells, and lysozyme-positive Paneth cells (p < 0.05) through Wnt and Notch pathway. The proliferation and differentiation stimulating effects of ML-329 and ML-446 on IECs in the jejunum, ileum, and colon were mediated by activating the Wnt pathway with increased expression of wnt, lrp5, and β-catenin genes and accumulation of β-catenin, and by downregulating the Notch signalling pathway with decreased expression of the activated notch protein. Lactobacillus could facilitate IUGR rat pups' intestinal development and enhance the proliferation of Paneth cells and goblet cells. These findings provide further insights into promotion of the intestinal development by breast milk-derived beneficial microbes in early life of the IUGR newborn rats.

CD226 Deficiency Alleviates Murine Allergic Rhinitis by Suppressing Group 2 Innate Lymphoid Cell Responses.

Allergic rhinitis (AR) is an immunoglobulin E-mediated type 2 inflammation of the nasal mucosa that is mainly driven by type 2 helper T cells (Th2) and type 2 innate lymphoid cells (ILC2s). CD226 is a costimulatory molecule associated with inflammatory response and is mainly expressed on T cells, natural killer cells, and monocytes. This study is aimed at elucidating the role of CD226 in allergic inflammatory responses in murine AR using global and CD4+ T cell-specific Cd226 knockout (KO) mice. AR nasal symptoms were assessed based on the frequency of nose rubbing and sneezing. Hematoxylin and eosin and periodic acid–Schiff staining and quantitative real-time PCR methods were used to determine eosinophils, goblet cells, and ILC2-associated mRNA levels in the nasal tissues of mice. CD226 levels on ILC2s were detected using flow cytometry, and an immunofluorescence double staining assay was employed to determine the number of ILC2s in the nasal mucosa. The results showed that global Cd226 KO mice, but not CD4+ T cell-specific Cd226 KO mice, exhibited attenuated AR nasal symptoms. Eosinophil recruitment, goblet cell proliferation, and Th2-inflammatory cytokines were significantly reduced, which resulted in the alleviation of allergic and inflammatory responses. ILC2s in the murine nasal mucosa expressed higher levels of CD226 after ovalbumin stimulation, and CD226 deficiency led to a reduction in the proportion of nasal ILC2s and ILC2-related inflammatory gene expression. Hence, the effect of CD226 on the AR mouse model may involve the regulation of ILC2 function rather than CD4+ T cells.

Protective effects of glaucocalyxin A on the airway of asthmatic mice.

The aim of this study is to investigate the protective effects of glaucocalyxin A (GLA) on airways in mouse models of asthma, concerning the inflammatory mediators, Th1/Th2 subgroup imbalance, and Toll-like receptor 4 (TLR4)/NF-κB signaling pathway. Hematoxylin and eosin/periodic acid–Schiff staining was used to observe the pathological changes in lung tissues. Inflammatory cytokine contents in the bronchoalveolar lavage fluid were detected by enzyme-linked immunosorbent assay. Protein expression levels were detected with Western blot, immunohistochemistry, and immunofluorescence. In vivo studies showed that, in ovalbumin (OVA)-induced asthmatic mouse models, the GLA treatments reduced the airway hyperresponsiveness and the secretion of inflammatory cells, declined the proliferation of goblet cells, decreased the levels of IL-4, IL-5, and IL-13, and increased the contents of interferon-γ and IL-12. Moreover, GLA inhibited the protein expression levels of TLR4, MyD88, TRAF6, and NF-κB in OVA-induced asthmatic mouse models. Further in vitro studies showed that GLA inhibited the expression of NF-κB, p-IκBα, tumor necrosis factor-α, IL-6, and IL-1β and blocked the nuclear transfer of NF-κB in lipopolysaccharide-stimulated RAW264.7 macrophages. Conclusively, GLA can inhibit the inflammatory responses in OVA-induced asthmatic mice and inhibit the release of inflammatory factors in LPS-induced RAW264.7 macrophages, which may be related to the inhibition of TLR4/NF-κB signaling pathway.

Role of Microbial Metabolites of Histidine in the Development of Colitis.

Colitis is a chronic relapsing inflammatory disease of colon. Clinical studies show that meat-rich diet plays a critical role in the relapse of colitis. However, it is unclear whether the microbial metabolites of histidine, which is an amino acid widely found in meat, have an impact on the health of the intestine. Six metabolites of histidine are given to IEC-6 cells. The cell activity measurement shows that imidazole propionate (IMP) is the most detrimental metabolite. Then, IMP is injected to mice by rectal administration, with blood and colon tissues collected for the measurement of colitis related parameters. The results show that treatment with IMP significantly increased NF-κB, iNOS, and IL-6, decreased number of goblet cell, and inhibited expressions of miR-146b. However, overexpression of miR-146b in mice rescues the decline of the physical condition. Additionally, Notch receptor 1 (Notch1) is identified as a target gene of miR-146b. Further analysis shows that miR-146b restored the abundance of goblet cells by regulating Notch1 signaling pathway. IMP is able to induce intestinal inflammation, impairs the intestinal barrier, and affects the proliferation of goblet cells. The underlined mechanism may partially contribute to the dysregulation of miR-146b/Notch1 axis.

MicroRNA-182-5p Attenuates Asthmatic Airway Inflammation by Targeting NOX4.

Bronchial asthma is characterized by chronic airway inflammation, airway hyperresponsiveness, and airway remodeling. MicroRNA (miRNA) has recently been implicated in the pathogenesis of asthma. However, the mechanisms of different miRNAs in asthma are complicated, and the mechanism of miRNA-182-5p in asthma is still unclear. Here, we aim to explore the mechanism of miRNA182-5p in asthma-related airway inflammation. Ovalbumin (OVA)-induced asthma model was established. MiRNA Microarray Analysis was performed to analyze the differentially expressed miRNAs in the asthma model. We found that the expression of miRNA-182-5p was significantly decreased in OVA-induced asthma. In vitro, IL-13 stimulation of BEAS-2B cells resulted in a significant up-regulation of NOX4 (nicotinamide adenine dinucleotide phosphate oxidase 4), accompanied by mitochondrial damage-induced apoptosis, NLRP3 (NOD-like receptor family pyrin domain-containing 3)/IL-1β activation, and reduced miRNA-182-5p. In contrast, overexpression of miRNA-182-5p significantly inhibited epithelial cell apoptosis and NLRP3/IL-1β activation. In addition, we found that miRNA-182-5p could bind to the 3’ untranscripted region of NOX4 mRNA and inhibit epithelial cell inflammation by reducing oxidative stress and mitochondrial damage. In vivo, miRNA-182-5p agomir treatment significantly reduced the percentage of eosinophils in bronchoalveolar lavage fluid, and down-regulated Th2 inflammatory factors, including IL-4, IL-5, and OVA induced IL-13. Meanwhile, miRNA-182-5p agomir reduced the peribronchial inflammatory cell infiltration, goblet cell proliferation and collagen deposition. In summary, targeting miRNA-182-5p may provide a new strategy for the treatment of asthma.

Eimeria pragensis infection alters the gut microenvironment to favor extrinsic shiga toxin-producing Escherichia coli O157:H7 colonization in mice.

We examined the effects of Eimeria pragensis infection on intestinal peristalsis, goblet cell proliferation and intestinal flora in C57BL/6 mice. Intestinal peristalsis was evaluated by radiography using barium at 7days post-infection (p.i.). The intestinal peristalsis of E. pragensis-infected mice was significantly suppressed compared with uninfected control mice. Twenty-three mice were divided into 5 groups of 4 or 5 mice each; 2 groups of mice were infected with E. pragensis and the others were kept uninfected. At 7days p.i., E. pragensis-infected and -uninfected mice were sacrificed to examine goblet cell numbers in the intestines, and significant decreases were observed only in the infected mice. Shiga toxin-producing Escherichia coli (STEC) O157:H7 was inoculated orally in mice both infected and uninfected with E. pragensis at 7days p.i., with the remaining mice used as uninoculated controls. When mice were sacrificed at 2days after STEC inoculation, STEC was only detected in the intestines of E. pragensis-infected mice. Colonization of STEC was also confirmed by immunohistochemistry on the surface of epithelial cells in concurrently infected/inoculated mice. Also, an overgrowth of residential E. coli was observed only in E. pragensis-infected mice. These results suggest that E. pragensis induces the suppression of intestinal peristalsis and modifies the intestinal environment to facilitate artificially introduced STEC colonization and multiplication, in addition to residential E. coli overgrowth.

Vitexin restores lung homeostasis by targeting vicious loop between inflammatory aggravation and autophagy mediated via multiple redox cascade and myeloid cells alteration in experimental allergic asthma

BackgroundAllergic asthma is one of the leading respiratory diseases with complex pathology. Attributes of vitexin, a trihydroxyflavone, has been studied to alleviate Th2 cytokines response in allergic asthma. However, its efficacy and underlying mechanism in mitigating allergic asthma particularly mediated by oxi-inflammatory stress, autophagy and apoptosis, yet to be delineated. PurposePresent study aimed to decipher efficacy and governing molecular mechanism of vitexin in mitigating allergic asthma particularly mediated by vicious loop of oxi-inflammatory stress, autophagy and apoptosis. MethodsTo ascertain this, OVA-LPS induced mice model was used and protective attributes of vitexin for different mediators, pathological facets and sensing pathways of allergic asthma were evaluated. ResultsVitexin treatment remarkably inhibited OVA-LPS induced inflammatory cell infiltration, mast cell activation, alveolar collapse, congestion, fibrosis in lung architecture. These results were accompanied by suppression of immune cells hyperactivation, mucus secretion, goblet cell proliferation, persistent inflammation which were affirmed by alleviation in levels of IgE, Th1/Th2/Th17, IL-4/IFN-γ, chemokines, endopeptidases (MMP-1, MMP-13), oxidative effectors with concomitant increase in IL-15, IL-10, MMP-9 and MMP-3. Additionally, noticeable decline in p-connexin 43, p-c-Fos, TGF-β, Smad2/3/4, Caspase9/3, LC3A/B expression and upregulation in beclin-1, p62 co-localization and Bcl2/Bax indicate reversal of lung vascular permeability, mast cell degranulation, fibrosis, apoptosis, autophagosome impairment. Subsequent allergic inflammatory cascades analysis revealed p-NF-κB, p-PI3K, p-Akt, p-p38, p-Stat3, GATA3 upregulation and p-PTEN downregulation in sensitized mice, which were decisively counteracted by vitexin. In silico studies signified target specificity of vitexin with these proteins. Suppression in myeloid cells activation and enhancements of Tregs demonstrated immunomodulatory potential of vitexin in allergic airways. ConclusionCollectively, to our knowledge, this is the first report that confers vitexin meditated multi-faceted protective attribute in mitigation of allergic asthma that could be linked to its suppressive effects on vicious cycle of pathological process particularly regulated via oxi-inflammation, autophagy and apoptosis. Thus, signify vitexin as safe therapeutic strategy.

Toxicity of Pb continuous and pulse exposure on intestinal anatomy, bacterial diversity, and metabolites of Pelophylax nigromaculatus in pre-hibernation

Amphibians are often exposed to pulse pollution due to fluctuational inputs of pollutants in water. Traditional ecotoxicology research is mainly performed under constant exposure conditions, which is not consistent with the true environmental pollution. Frogs are sensitive to changes in water pollutants in pre-hibernation. Thus, to understand the toxicity difference to continuous and pulse exposure in environmental concentrations of Pb (100 μg/L), Pelophylax nigromaculatus adults were exposed to short-term treatments (8 days) in pre-hibernation. Individual mortality, intestinal anatomical structure, bacterial diversity, and metabolites were measured in a control group (CON), a Pb continuous treatment group (CEPb) and a Pb pulse treatment group (PEPb). The results showed that PEPb significantly increased individual mortality, compared to the control group and CEPb. PEPb induced pathological changes in the small intestinal tissues, such as mucosal erosion, swollen and distorted villi, large vacuoles, and the proliferation of goblet cells. In addition, PEPb altered the structure and diversity of intestinal bacteria, resulting in an increase in some pathogenic bacteria (e.g. Bacteroides and Ruminococcus) and a decrease in beneficial bacteria (e.g. Cetobacterium and Akkermansia). Both CEPb and PEPb significantly changed intestinal metabolites and metabolic pathways. Moreover, PEPb has a significant effect on the metabolism of amino acids by increasing the content of 5-Aminopentanoic acid, cis-4-Hydroxy-l-proline, Glycocholic acid, l-Alanine, and l-Isoleucine. We concluded that PEPb may lead to intestine impairment of P. nigromaculatus in pre-hibernation by inducing intestinal structural integrity destruction, bacterial imbalance, and metabolic dysfunction, resulting in a significant increase in mortality. The study provides new insights for understanding the intestinal responses of frogs to pulse metal exposure.

Salidroside Mitigates Airway Inflammation in Asthmatic Mice via the AMPK/Akt/GSK3β Signaling Pathway

Introduction: This study aimed to explore the effects and mechanisms of salidroside (SAL) in airway inflammation in asthmatic mice. Methods: Mice were sensitized with ovalbumin (OVA) to establish an asthma model. They were divided into the control group, OVA group, SAL low-dose group (SAL-L), SAL high-dose group (SAL-H), and dexamethasone (DXM) group. The airway reactivity of the mice was measured, and the total cells, neutrophils, eosinophils, and lymphocytes were counted, respectively. The levels of IL-4, IL-5, IL-13, and IFN-γ in bronchoalveolar lavage fluid (BALF) were detected by ELISA. Immunohistochemistry was used to detect the expression levels of p-AMPK, p-Akt, and p-GSK3β. Western blot was used to detect cytokine levels in lung tissue and p-AMPK, p-Akt, and p-GSK3β levels in LPS-induced 16HBE cells. Results: The airway hyperresponsiveness of asthmatic mice in the SAL-H group decreased (p < 0.05), and the total number of cells, neutrophils, eosinophils, and lymphocytes decreased significantly (p < 0.05). In addition, the airways of mice showed airway inflammatory infiltration and goblet cell proliferation, and the corresponding cellular inflammatory factors IL-4, IL-5, and IL-13 were significantly decreased. However, the expression of IFN-γ in BALF and lung tissues was increased (p < 0.05). Moreover, after the mice were treated with SAL, the phosphorylation level of AMPK was significantly increased, which further reduced the phosphorylation levels of Akt and GSK3β (p < 0.05). Both SAL and AMPK inhibitors exerted effects on LPS-induced 16HBE cells, consistent with in vivo results. Conclusion: SAL can inhibit bronchial hyperresponsiveness and reduce tracheal inflammation by increasing AMPK phosphorylation and inhibiting Akt and GSK3β signaling pathways.