Inflammatory Response In Asthma Research Articles

Impact of Air Pollutants on Lung Function and Inflammatory Response in Asthma in Shanghai.

Air pollution is a leading public health issue. This study investigated the effect of air quality and pollutants on pulmonary function and inflammation in patients with asthma in Shanghai. The study monitored 27 asthma outpatients for a year, collecting data on weather, patient self-management [daily asthma diary, peak expiratory flow (PEF) monitoring, medication usage], spirometry and serum markers. To explore the potential mechanisms of any effects, asthmatic mice induced by ovalbumin (OVA) were exposed to PM 2.5. Statistical and correlational analyses revealed that air pollutants have both acute and chronic effects on asthma. Acute exposure showed a correlation between PEF and levels of ozone (O 3) and nitrogen dioxide (NO 2). Chronic exposure indicated that interleukin-5 (IL-5) and interleukin-13 (IL-13) levels correlated with PM 2.5 and PM 10 concentrations. In asthmatic mouse models, exposure to PM 2.5 increased cytokine levels and worsened lung function. Additionally, PM 2.5 exposure inhibited cell proliferation by blocking the NF-κB and ERK phosphorylation pathways. Ambient air pollutants exacerbate asthma by worsening lung function and enhancing Th2-mediated inflammation. Specifically, PM 2.5 significantly contributes to these adverse effects. Further research is needed to elucidate the mechanisms by which PM 2.5 impacts asthma.

Neuromedin-U Mediates Rapid Activation of Airway Group 2 Innate Lymphoid Cells in Mild Asthma.

In asthma, sputum group 2 innate lymphoid cells (ILC2) are activated within 7h after allergen challenge. Neuroimmune interactions mediate rapid host responses at mucosal interfaces. In murine models of asthma, lung ILC2 co-localize to sensory neuronal termini expressing the neuropeptide, neuromedin U (NMU) and NMU stimulates type 2 cytokines secretion by ILC2 with additive effects to alarmins, in vitro. Investigate effect of NMU/NMUR1 axis on early activation of ILC2 in asthma. M ild asthmatics (n=8) were enrolled in a diluent-controlled, allergen-inhalation challenge study. Sputum ILC2 expression of NMU receptor 1 (NMUR1) and T2 cytokines were enumerated by flow cytometry and airway NMU levels were assessed by ELISA. This was compared to samples from moderate-severe asthmatics (n=9). Flow sort-purified and ex-vivo expanded ILC2 were used for functional assays and transcriptomic analyses. Significant increases in sputum ILC2 expressing NMUR1 were detected 7h post- allergen versus diluent challenge where the majority of NMUR1+ILC2 expressed IL-5/IL-13. Sputum NMUR1+ILC2 were significantly greater in mild versus moderate-severe asthmatics and NMUR1+ILC2 correlated inversely with the dose of inhaled corticosteroid in the latter group. Co-culturing with alarmins upregulated NMUR1 in ILC2, which was attenuated by dexamethasone. NMU stimulated T2 cytokine expression by ILC2, maximal at 6h was abrogated by dexamethasone or specific signaling inhibitors for mitogen-activated protein kinase ½, phospho-inositol 3 kinase but not IL-33 signaling moiety MyD88, in vitro. The NMU/NMUR1 axis stimulates rapid effects on ILC2, and maybe an important early activator of these cells in eosinophilic inflammatory responses in asthma.

Knockdown of KIF23 alleviates the progression of asthma by inhibiting pyroptosis

BackgroundAsthma is a chronic disease affecting the lower respiratory tract, which can lead to death in severe cases. The cause of asthma is not fully known, so exploring its potential...

The effect of N-eicosapentaenoyl ethanolamine on the regulation of cytokine synthesis by blood cells of patients with bronchial asthma <I>in vitro</I>

Introduction. Bronchial asthma is characterized by heterogeneity, multiple phenotypes, and varying clinical manifestations. Cytokines play a crucial role in the inflammatory response in asthma. The quantity, as well as the ratio of certain cytokines, determines the mechanism and type of inflammatory response in asthma, upon which the effectiveness of treatment of this disease depends. That is why the development of new methods of treating patients with asthma, aimed at correcting cytokine imbalance, is required. One of the promising substances is N-eicosapentaenoyl-ethanolamine (NAE-EPA), which exhibits anti-inflammatory properties by affecting cytokines, but remains poorly studied.Aim. To study the dose-dependent effect of N-eicosapentaenoyl-ethanolamine on the production of cytokines by peripheral blood cells, in vitro, in subjects with asthma.Materials and methods. The object of the study was whole blood, diluted 1:5 with culture medium of 15 patients with mild to moderate controlled asthma and 16 healthy subjects. The in vitro experiment was carried out in lipopolysaccharide-stimulated (LPS) blood samples (incubation with LPS at 37°C for 30 minutes). Then, the experimental substance N-acylethanolamine eicosapentaenoic acid (NAE EPA) was added in concentrations of 1.0; 5.0, and 10.0 µM and incubated at 37°C for 6 hours with gentle mixing. Cytokine levels (IL-2, IL-4, IL-6, IL-10, IL17A, TNF-α, and INF-γ) were studied by enzyme-linked immunoassay.Results. Analysis of the level of cytokines in patients with asthma showed that an increase in the plasma levels of IL-2, TNF-α, IL-6, and IL-17A is accompanied by a decrease in the level of regulatory IL-10. When NAE EPA was added at a dosage of 1 µM, no statistically significant changes were detected. Exposure to the experimental substance at a dose of 5 µM contributed to a decrease in IL-6 in the blood cells of patients by 19% (p ˂ 0.05). Exposure to NAE EPA at 10 µM produced the greatest number of statistically significant changes in cytokine levels. There was a decrease in IL-17A by 15% (p ˂ 0.05), IL-2 by 14% (p ˂ 0.05), IL-6 by 50% (p ˂ 0.01), and TNF-α by 10% (p ˂ 0.05) relative to values before exposure.Conclusion. N-eicosapentaenoyl ethanolamine shows potential as a regulator of pro- and anti-inflammatory cytokine synthesis in bronchial asthma with a predominant Th-17 type of immune response. The results obtained may contribute to the development of new treatment strategies for patients with asthma.

Montelukast: results and prospects for applications in pediatric practice

The Centers for Disease Control and Prevention reports that more than 4 million children have been diagnosed with asthma. Currently, there is no treatment that could prevent the development of asthma or change its natural course over long-term follow-up. However, the disease can be controlled using treatments used in clinical practice. For persistent asthma in children aged 5 years and younger, low doses of inhaled glucocorticosteroids are recommended, as well as the administration of montelukast, a leukotriene receptor antagonist. In addition, montelukast is prescribed to patients with allergic rhinitis as an alternative to or in combination with oral antihistamines or nasal corticosteroids. Leukotrienes are lipid mediators that play a key role in acute and chronic inflammation and allergic diseases. They exhibit their biological effects by binding to specific G-protein-coupled receptors. Each subtype of the leukotriene receptor has unique functions and expression patterns. Leukotrienes play an important role in various allergic diseases, including bronchial asthma and allergic rhinitis. Montelukast is a cysteinyl leukotriene receptor-1 antagonist widely used to suppress the inflammatory response in asthma and allergic rhinitis. This review briefly summarizes the biology of leukotrienes and their receptors, recent developments in the field of antileukotriene drugs and the prospects for their different therapeutic applications. The role of antileukotriene drugs and key indications for the use of montelukast in the complex therapy of asthma and allergic rhinitis in children have been determined.

Blocking μ-opioid receptor by naltrexone exaggerates oxidative stress and airway inflammation via the MAPkinase pathway in a murine model of asthma

Opioids regulate various physiological and pathophysiological functions, including cell proliferation, immune function, obesity, and neurodegenerative disorders. They have been used for centuries as a treatment for severe pain, binding to opioid receptors a specific G protein-coupled receptor. Common opioids, like β-endorphin, [D-Ala2, N-MePhe4, Gly-ol]-enkephalin (DAMGO), and dynorphins, have analgesic effects. The use of a potent antagonist, like naltrexone hydrochloride, to block the effects of mu Opioid Receptor (μOR) may result in the withdrawal of physiological effects and could potentially impact immune responses in many diseases including respiratory disease. Asthma is a respiratory disease characterized by airway hyperresponsiveness, inflammation, bronchoconstriction, chest tightness, stress generation and release of various cytokines. Airway inflammation leads recruitment and activation of immune cells releasing mediators, including opioids, which may modulate inflammatory response by binding to their respective receptors. The study aims to explore the role of μOR antagonist (naltrexone) in regulating asthma pathophysiology, as the regulation of immune and inflammatory responses in asthma remains unclear. Balb/c mice were sensitized intranasally by 1% TDI and challenged with 2.5% TDI. Naltrexone hydrochloride (1 mg/kg body weight) was administered through intraperitoneal route 1 h before TDI induction. Blocking μOR by naltrexone exacerbates airway inflammation by recruiting inflammatory cells (lymphocytes and neutrophils), enhancing intracellular Reactive oxygen species in bronchoalveolar lavage fluid (BALF), and inflammatory mediator (histamine, Eosinophil peroxidase and neutrophil elastase) in lungs. Naltrexone administration modulated inflammatory cytokines (TNF-α, IL-4, IL-5, IL-6, IL-10, and IL-17A), and enhanced IgE and CRP levels. Naltrexone administration also increased the expression of NF-κB, and phosphorylated p-P38, p-Erk, p-JNK and NF-κB by inhibiting the μOR. Docking study revealed good binding affinity of naltrexone with μOR compared to δ and κ receptors. In future it might elucidate potential therapeutic against many respiratory pathological disorders. In conclusion, μOR blocking by naltrexone regulates and implicates inflammation, bronchoconstriction, and lung physiology.

Haemophilus influenzae and Moraxella catarrhalis in sputum of severe asthma with inflammasome and neutrophil activation.

Because of altered airway microbiome in asthma, we analysed the bacterial species in sputum of patients with severe asthma. Whole genome sequencing was performed on induced sputum from non-smoking (SAn) and current or ex-smoker (SAs/ex) severe asthma patients, mild/moderate asthma (MMA) and healthy controls (HC). Data were analysed by asthma severity, inflammatory status and transcriptome-associated clusters (TACs). α-diversity at the species level was lower in SAn and SAs/ex, with an increase in Haemophilus influenzae and Moraxella catarrhalis, and Haemophilus influenzae and Tropheryma whipplei, respectively, compared to HC. In neutrophilic asthma, there was greater abundance of Haemophilus influenzae and Moraxella catarrhalis and in eosinophilic asthma, Tropheryma whipplei was increased. There was a reduction in α-diversity in TAC1 and TAC2 that expressed high levels of Haemophilus influenzae and Tropheryma whipplei, and Haemophilus influenzae and Moraxella catarrhalis, respectively, compared to HC. Sputum neutrophils correlated positively with Moraxella catarrhalis and negatively with Prevotella, Neisseria and Veillonella species and Haemophilus parainfluenzae. Sputum eosinophils correlated positively with Tropheryma whipplei which correlated with pack-years of smoking. α- and β-diversities were stable at one year. Haemophilus influenzae and Moraxella catarrhalis were more abundant in severe neutrophilic asthma and TAC2 linked to inflammasome and neutrophil activation, while Haemophilus influenzae and Tropheryma whipplei were highest in SAs/ex and in TAC1 associated with highest expression of IL-13 type 2 and ILC2 signatures with the abundance of Tropheryma whipplei correlating positively with sputum eosinophils. Whether these bacterial species drive the inflammatory response in asthma needs evaluation.

Effect of NO2 exposure on airway inflammation and oxidative stress in asthmatic mice

Nitrogen dioxide (NO2) is a widespread air pollutant. Epidemiological evidence indicates that NO2 is associated with an increase of incidence rate and mortality of asthma, but its mechanism is still unclear. In this study, we exposed mice to NO2 (5 ppm, 4 h per day for 30 days) intermittently to investigate the development and potential toxicological mechanisms of allergic asthma. We randomly assigned 60 male Balb/c mice to four groups: saline control, ovalbumin (OVA) sensitization, NO2 alone, and OVA+NO2 groups. The involved mechanisms were found from the perspective of airway inflammation and oxidative stress. The results showed that NO2 exposure could aggravate lung inflammation in asthmatic mice, and airway remodeling was characterized by significant thickening of the airway wall and infiltration of inflammatory cells. Moreover, NO2 would aggravate the airway hyperresponsiveness (AHR), which is characterized by significantly elevated inspiratory resistance (Ri) and expiratory resistance (Re), as well as decreased dynamic lung compliance (Cldyn). In addition, NO2 exposure promoted pro-inflammatory cytokines (IL-6 and TNF-α) and serum immunoglobulin (IgE) production. The imbalance of Th1/Th2 cell differentiation (IL-4 increased, IFN-γ reduced, IL-4/IFN-γ significantly increased) played a key role in the inflammatory response of asthma under NO2 exposure. In a nutshell, NO2 exposure could promote allergic airway inflammation and increase asthma susceptibility. The levels of ROS and MDA among asthmatic mice exposed to NO2 increased significantly, while GSH levels sharply decreased. These findings may provide better toxicological evidence for the mechanisms of allergic asthma risk due to NO2 exposure.

Meta-omics profiling of the gut-lung axis illuminates metabolic networks and host-microbial interactions associated with elevated lung elastance in a murine model of obese allergic asthma.

Obesity and associated changes to the gut microbiome worsen airway inflammation and hyperresponsiveness in asthma. Obesogenic host-microbial metabolomes have altered production of metabolites that may influence lung function and inflammatory responses in asthma. To understand the interplay of the gut microbiome, metabolism, and host inflammation in obesity-associated asthma, we used a multi-omics approach to profile the gut-lung axis in the setting of allergic airway disease and diet-induced obesity. We evaluated an immunomodulator, nitro-oleic acid (NO2-OA), as a host- and microbial-targeted treatment intervention for obesity-associated allergic asthma. Allergic airway disease was induced using house dust mite and cholera toxin adjuvant in C57BL6/J mice with diet-induced obesity to model obesity-associated asthma. Lung function was measured by flexiVent following a week of NO2-OA treatment and allergen challenge. 16S rRNA gene (from DNA, taxa presence) and 16S rRNA (from RNA, taxa activity) sequencing, metabolomics, and host gene expression were paired with a Treatment-Measured-Response model as a data integration framework for identifying latent/hidden relationships with linear regression among variables identified from high-dimensional meta-omics datasets. Targeting both the host and gut microbiota, NO2-OA attenuated airway inflammation, improved lung elastance, and modified the gut microbiome. Meta-omics data integration and modeling determined that gut-associated inflammation, metabolites, and functionally active gut microbiota were linked to lung function outcomes. Using Treatment-Measured-Response modeling and meta-omics profiling of the gut-lung axis, we uncovered a previously hidden network of interactions between gut levels of amino acid metabolites involved in elastin and collagen synthesis, gut microbiota, NO2-OA, and lung elastance. Further targeted metabolomics analyses revealed that obese mice with allergic airway disease had higher levels of proline and hydroxyproline in the lungs. NO2-OA treatment reduced proline biosynthesis by downregulation of pyrroline-5-carboxylate reductase 1 (PYCR1) expression. These findings are relevant to human disease: adults with mild-moderate asthma and BMI ≥ 25 had higher plasma hydroxyproline levels. Our results suggest that changes to structural proteins in the lung airways and parenchyma may contribute to heightened lung elastance and serve as a potential therapeutic target for obese allergic asthma.

PP4 deficiency contributes to DEP exacerbated epithelial barrier dysfunction and airway inflammation in asthmatic patients

Abstract Diesel exhaust particles (DEP) emitted from motor vehicle or heavy-duty industries is thought to be the major source of air pollutants that lead to the rapid increase and worsening of allergic disease, such as asthma. In asthma, exposure to DEP has been linked to aberrant epithelial barrier integrity, which leads to the promotion of allergen delivery into the subepithelia and induced alarmins (IL-33, IL-25 and thymic stromal lymphopoietin (TSLP)) release to promote Th2-mediated inflammation. However, it is still not known the detail mechanism of airway epithelial barrier in response to DEP. In this study, we fund that PP4 expression was decreased in DEP-challenged human bronchial epithelial cells and air-pollution animal model. Moreover, silencing PP4 decreased E-cadherin and barrier integrity through and activated Src kinase and increased expression of Slug. Sequentially, transactivating the EGFR phosphorylation led to increased alarmin synthesis. Overexpression of PP4 wild type, but not phosphatase mutant, prevented DEP-induced loss of airway epithelial E-cadherin expression and decreased alarmin release, suggested that phosphatase activity is critical to maintain epithelial integrity and alarmin production. Primary human bronchial epithelial cells (HBECs) from mild and severe asthmatic patients showed a significantly low TJ integrity in ALI cultures in response to DEP, compared with HBECs from healthy subjects. Our data demonstrate that exposure to DEP causes a significant reduction in expression of PP4 leading to decreased epithelial barrier function might accelerate the allergen-induced airway inflammatory response in asthma. Supported by grants from (MOST 110-2320-B-038-065-MY3) from the Ministry of Science and Technology of Taiwan.

Inulin alleviates offspring asthma by altering maternal intestinal microbiome composition to increase short-chain fatty acids.

Technically, symptom of offspring asthma is also closely reliant on its maternal high-fiber diet as well as the intestinal microbiome. Fruits and vegetables are abundant in inulin, and this naturally soluble dietary fiber is endowed with a potential value on offspring asthma control through the maternal intake, but the mechanism now remains less studied. In this study, rats were given with inulin-included drinking water, whereas in normal group rats were allowed with normal water. Afterwards, we analyzed both the formations of the offspring intestinal microbiome ahead of asthma model establishment and of the maternal intestinal microbiome through high throughput sequence and the short-chain fatty acids (SCFAs) by metabolomic analysis. Subsequently, lung inflammation indexes were detected by Elisa, and the expression of short-chain fatty acid receptors (GPR41, GPR43) in the offspring of asthma models were evaluated through qPCR assay. Inulin intake resulted in altered maternal intestinal microbiome composition, with a significant increase in SCFAs-producing bacteria (mainly Bifidobacterium), attenuating the asthmatic inflammatory response in the offspring. Meanwhile, inulin intake during pregnancy modulates the composition of the intestinal microbiome of the offspring, and this alteration appears before the onset of asthma, hence, there should be further studies onto the impacts of offspring's intestinal microbiome on asthma procession.

Scorpio and centipede ameliorate asthma by inhibiting the crosstalk between ferroptosis and inflammation in airway epithelial cells.

We previously revealed that scorpio and centipede (SC) improve the inflammatory response in asthma, whereas it is unclear whether ferroptosis is involved in this process. The asthmatic mouse model was established and lung tissues were collected for histopathological examination. The levels of tumor necrosis factor-α (TNF-α), interleukin- (IL-)1β, Fe2+, malondialdehyde (MDA), glutathione peroxidase 4 (GPX4), ferritin heavy chain 1(FTH1), and reactive oxygen species (ROS) were assessed in asthmatic mice and mouse airway epithelial cells. Our results showed that ferroptosis was induced in asthmatic mice, as evidenced by the reduction of FTH1 and GPX4 expression and the increase of MDA and Fe2+ levels (all P<0.05). Ferrostatin-1 repressed inflammation and ferroptosis of asthmatic mice. Additionally, SC significantly inhibited the levels of TNF-α, IL-1β, MDA, and Fe2+, while enhancing FTH1 and GPX4 expression. However, SC plus erastin showed the reverse results. Moreover, ferroptosis remarkably increased in asthmatic airway epithelial cells, while SC suppressed ferroptosis of the cells (all P<0.05). SC ameliorated asthma by inhibiting the crosstalk between ferroptosis and inflammation in airway epithelial cells.

The Impact of Tezepelumab in Uncontrolled Severe Asthma: A Systematic Review of Randomized Controlled Trials.

Asthma, a chronic illness, is characterized by inflammation and airway constriction. Uncontrolled severe asthma is related to poor quality of life and increased utilization of health resources. Conventional treatments are associated with a significant amount of adverse effects. Recent years have seen the identification of various molecular effectors and signaling pathways as interesting targets for the biological therapy of severe asthma that is resistant to current therapies. Because they only target some downstream components of the inflammatory response in asthma, leaving other components unaffected, current biologic treatments only lower the exacerbation rate by 50%. If we focus on the upstream mediators of the inflammatory response in asthma, it might have a greater effect and be more efficient. Tezepelumab is a human monoclonal IgG2 antibody that specifically binds to thymic stromal lymphopoietin (TSLP) at the level of its TSLPR (thymic stromal lymphopoietin receptor) binding site, inhibiting the interaction between human TSLP and TSLPR. It is being used to treat the cytokines on the respiratory epithelial layer known as "alarmins." It is the only biologic drug available for treating severe uncontrolled asthma, despite limitations in biomarker and phenotype. In light of recent developments, the lack of knowledge on tezepelumab prompts us to publish a comprehensive systematic review. We discovered that regardless of blood eosinophil level and fractional exhaled nitric oxide levels, tezepelumab dramatically lowers asthma exacerbation in patients with severe uncontrolled asthma when compared to placebo. Tezepelumab also lessens patients' demand for healthcare resources while improving clinical indicators of lung function, health-related quality of life, and asthma management in patients. Tezepelumab plays a role in enhancing pre-bronchodilator FEV1 and lowering blood eosinophil count and fractional exhaled nitric oxide in patients with or without chronic allergies (FeNO). There have been no reports of fatalities or severe adverse events connected to tezepelumab.

Lactobacillus fermentum CECT5716 Alleviates the Inflammatory Response in Asthma by Regulating TLR2/TLR4 Expression.

BackgroundAsthma is a chronic disease, which is harmful to the health of the body and the quality of life. Supplementation of Lactobacillus can affect the immune environment of the lungs through the gut-lung axis. This study aimed to explore the potential regulatory targets of Lactobacillus to relieve inflammation in asthma and determine a new approach for improving asthma.MethodsA mouse ovalbumin (OVA)-induced model was constructed. OVA mice were supplemented with Lactobacillus fermentum CECT5716 by gavage. The gut microbiota composition of normal and OVA mice was analyzed using 16S ribosomal DNA identification. BALF, serum, lung tissues, and duodenal tissues were collected. Wright’s staining was performed to determine the cell content of the alveolar lavage fluid. Hematoxylin-eosin staining, Masson staining, and periodic acid-Schiff staining were performed to observe the improvement in the lungs of OVA mice supplemented with Lactobacillus. Immunofluorescence was performed to measure the severity of the intestinal barrier leakage. Enzyme-linked immunosorbent assay was carried out to determine the expression levels of inflammatory cell factors, while quantitative reverse transcription-polymerase chain reaction and western blotting were performed to detect the levels of toll-like receptor 2 (TLR2)/TLR4 expression and cell adhesion factors.ResultsCompared with Control mice, OVA mice exhibited malignant conditions, such as intestinal leakage and lung edema. After supplementation with Lactobacillus, the inflammatory cell content in the bronchoalveolar lavage fluid decreased, and the inflammatory response was alleviated. The level of TLR2/TLR4 expression was reduced. The inflammatory cell infiltration in the airway mucosa of OVA mice was improved, alveolar swelling was reduced and the basement membrane appeared thinner.ConclusionThe Lactobacillus inhibited the TLR2/TLR4 expression in OVA mice. Supplementation with Lactobacillus can alleviate the inflammatory response in OVA mice, inhibit pulmonary fibrosis, and treat asthma.

Regulatory T Cells, a Viable Target Against Airway Allergic Inflammatory Responses in Asthma.

Asthma is a multifactorial disorder characterized by the airway chronic inflammation, hyper-responsiveness (AHR), remodeling, and reversible obstruction. Although asthma is known as a heterogeneous group of diseases with various clinical manifestations, recent studies suggest that more than half of the clinical cases are ‘‘T helper type 2 (Th2)-high’’ type, whose pathogenesis is driven by Th2 responses to an inhaled allergen from the environmental exposures. The intensity and duration of inflammatory responses to inhaled allergens largely depend on the balance between effector and regulatory cells, but many questions regarding the mechanisms by which the relative magnitudes of these opposing forces are remained unanswered. Regulatory T cells (Tregs), which comprise diverse subtypes with suppressive function, have long been attracted extensive attention owing to their capability to limit the development and progression of allergic diseases. In this review we seek to update the recent advances that support an essential role for Tregs in the induction of allergen tolerance and attenuation of asthma progression once allergic airway inflammation established. We also discuss the current concepts about Treg induction and Treg-expressed mediators relevant to controlling asthma, and the therapies designed based on these novel insights against asthma in clinical settings.

Interleukin‑27 ameliorates allergic asthma by alleviating the lung Th2 inflammatory environment.

Interleukin (IL)-27 can inhibit the differentiation of Th2 cells and plays a role in the development of asthma. However, whether the therapeutic administration of IL-27 in a mouse model of asthma can inhibit allergic responses remains a matter of debate. Additionally, the mechanisms through which IL-27 ameliorates inflammatory responses in asthma are not yet fully understood. Thus, the aim of the present study was to examine the effects of IL-27 on asthma using a mouse model and to elucidate the underlying mechanisms. For this purpose, mice received an intranasal administration of IL-27 and the total and differential cell counts, levels of cytokines and type 1 regulatory T (Tr1) cells in the lungs were detected. The protein and mRNA levels of signal transducer and activator of transcription (STAT)1 and STAT3 were analyzed and airway remodeling was assessed. The results indicated that IL-27 did not ameliorate airway inflammation, airway hyperresponsiveness, and airway remolding when administrated therapeutically. Preventatively, the administration of IL-27 decreased the concentrations of Th2 cytokines and increased the number of Tr1 cells. The protein and mRNA levels of STAT1 and STAT3 were increased. Taken together, these findings demonstrate that the prophylactic administration of IL-27 ameliorates asthma by alleviating the lung Th2 inflammatory environment through the restoration of both the STAT1 and STAT3 pathways. IL-27 may thus prove to be useful as a novel agent for the prevention of asthma.

Association between GSTM1, GSTT1 gene polymorphisms and asthma in adult patients from Tikrit population of Iraq

Introduction and Aim: Asthma is known as a polygenic and multifactorial disease. The underlying debate about the role of genetics in the development of asthma is still unclear. The objectives of this research are to examine whether the GSTM1 and GSTT1 gene polymorphisms are associated with asthma susceptibility. Materials and Methods: A total of 70 patients with asthma and 20 healthy individuals were investigated in this study. Genotyping was carried out by using PCR protocol for analysis of GSTM1 and GSTT1 null/positive genotypes. Results: Patients with asthma (34.285%) demonstrated a greater prevalence of the GSTM1, GSTT1 (-) genotype than the healthy subject (10%, P-value 0.012). A positive correlation was found between GSTT1, GSTM1 (+) genotype and healthy individuals (40%) compared with asthmatic patients (24.285%). Conclusion: The results of this research support the idea that GSTM1, GSTT1 (-) genotype may play critical roles in asthmatic inflammatory response. Further experimental investigations are needed to estimate the role of GSTM1 and GSTT1 polymorphisms in asthma.

Asthma and obesity: endotoxin another insult to add to injury?

Low-grade inflammation is often an underlying cause of several chronic diseases such as asthma, obesity, cardiovascular disease, and type 2 diabetes mellitus (T2DM). Defining the mediators of such chronic low-grade inflammation often appears dependent on which disease is being investigated. However, downstream systemic inflammatory cytokine responses in these diseases often overlap, noting there is no doubt more than one factor at play to heighten the inflammatory response. Furthermore, it is increasingly believed that diet and an altered gut microbiota may play an important role in the pathology of such diverse diseases. More specifically, the inflammatory mediator endotoxin, which is a complex lipopolysaccharide (LPS) derived from the outer membrane cell wall of Gram-negative bacteria and is abundant within the gut microbiota, and may play a direct role alongside inhaled allergens in eliciting an inflammatory response in asthma. Endotoxin has immunogenic effects and is sufficiently microscopic to traverse the gut mucosa and enter the systemic circulation to act as a mediator of chronic low-grade inflammation in disease.Whilst the role of endotoxin has been considered in conditions of obesity, cardiovascular disease and T2DM, endotoxin as an inflammatory trigger in asthma is less well understood. This review has sought to examine the current evidence for the role of endotoxin in asthma, and whether the gut microbiota could be a dietary target to improve disease management. This may expand our understanding of endotoxin as a mediator of further low-grade inflammatory diseases, and how endotoxin may represent yet another insult to add to injury.

Pingchuan formula improves allergic asthma in mice through inhibiting nuclear factor-kappa B / mitogen-activated protein kinase signaling pathway.

To examine the role and decipher the mechanism of Pingchuan formula (PCF) in treating allergic asthma. The mice were treated with saline, dexamethasone (DXM) and PCF for 1 week after the asthma model was established and their respiratory function including respiratory resistance (RI), pulmonary dynamic compliance (Cdyn) and maximum voluntary ventilation (MVV) were measured. In addition, cellular changes in bronchoalveolar lavage fluid (BALF) and pathological changes in lung biopsy as well as the expression level of -smooth muscle actin (α-SMA), transforming growth factor-beta1 (TGF-α1) in BALF and interleukin-5 (IL-5), interleukin-13 (IL-13), tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), nuclear factor-kappa B-p65 (NF-κBp65), inhibitor-α of nuclear transcription factor κB (IκBα), p38 mitogen-activated protein kinase (p38MAPK), c-jun n-terminal kinase (JNK) and its phosphorylated proteins in lung tissue were also examined and compared among different groups. Our data suggested that the respiratory functions were significantly improved and the pathological changes ameliorated in the DXM group and the PCF group compared to the model group. Both DXM and PCF effectively decreased the number of eosinophils, lymphocytes, and neutrophils in BAL as well as the secretion of α-SMA and TGF-α1, IL-5, IL-13, while increased the expression of TNF-α and IFN-γ. Furthermore, our study indicated that the NF-κBp65, IκBα, p38MAPK and JNK pathways were inhibited under the treatment of PCF. Our data indicated that PCF can attenuate the inflammatory response in asthma through inhibiting the NF-κB/MAPK signaling pathway. This study not only supported the use of PCF in allergic asthma in clinic but also shed light upon afurther understanding of thediseasepathogenesis.

Cysteinyl leukotriene induces eosinophil extracellular trap formation via cysteinyl leukotriene 1 receptor in a murine model of asthma

Purpose Eosinophils are one of the main cells responsible to the inflammatory response in asthma by the release of inflammatory molecules such as cytokines, reactive oxygen species (ROS), cytotoxic granule, eosinophil extracellular trap (EET), and lipid mediators as cysteinyl leukotriene (cysLT). The interconnections between these molecules are not fully understood. Here, we attempted to investigate the cysLT participation in the mechanisms of EET formation in an asthma model of OVA challenge. Materials and methods Before intranasal challenge with OVA, BALB/cJ mice were treated with a 5-lipoxygenase-activating protein (FLAP) inhibitor (MK-886), or with a cysLT1 receptor antagonist (MK-571) and the lung and bronchoalveolar lavage fluid (BALF) were analyzed. Results We showed that OVA-challenged mice treated with MK-886 or MK-571 had a decrease in inflammatory cells, goblet cells hyperplasia, and eosinophil peroxidase (EPO) activity in the airway. However, only OVA-challenged mice treated with MK-571 had an improvement in lung function. Also, treatments with MK-886 or MK-571 decreased Th2 cytokines levels in the airway. Moreover, we observed that OVA-challenged mice treated with MK-886 or MK-571 had a decrease in EET formation in BALF. We also verified that EET release was not due to cell death because the cell viability remained the same among the groups. Conclusion We revealed that the decrease in cysLT production or cysLT1 receptor inhibition by MK-886 or/and MK-571 treatments, respectively reduced EET formation in BALF, showing that cysLT regulates the activation process of EET release in asthma.