Recent advances in the pathophysiology of asthma

The Role of Aldose Reductase in Polyol Pathway: An Emerging Pharmacological Target in Diabetic Complications and Associated Morbidities

The expression of aldose reductase leads to a variety of biological and pathological effects. It is a multifunctional enzyme which has a tendency to reduce aldehydes to the corresponding sugar.alcohol. In diabetic conditions, the aldose reductase enzyme converts glucose into sorbitol using nicotinamide adenine dinucleotide phosphate as a cofactor. It is a key enzyme in polyol pathway which is a surrogate course of glucose metabolism. The polyol pathway has a significant impact on the aetiology of complications in individuals with end-stage diabetes. The exorbitant level of sorbitol leads to the accumulation of intracellular reactive oxygen species in diabetic heart, neurons, kidneys, eyes and other vasculatures, leading to many complications and pathogenesis. Recently, the pathophysiological role of aldose reductase has been explored with multifarious perspectives. Research on aldose reductase suggest that besides implying in diabetic complications, the enzyme also turns down the lipid-derived aldehydes as well as their glutathione conjugates. Although aldose reductase has certain lucrative role in detoxification of toxic lipid aldehydes, its overexpression leads to intracellular accumulation of sorbitol which is involved in secondary diabetic complications, such as neuropathy, cataractogenesis, nephropathy, retinopathy and cardiovascular pathogenesis. Osmotic upset and oxidative stress are produced by aldose reductase via the polyol pathway. The inhibition of aldose reductase alters the activation of transcription factors like NF-ƙB. Moreover, in many preclinical studies, aldose reductase inhibitors have been observed to reduce inflammation-related impediments, such as asthma, sepsis and colon cancer, in diabetic subjects. Targeting aldose reductase can bestow a novel cognizance for this primordial enzyme as an ingenious strategy to prevent diabetic complications and associated morbidities. In this review article, the significance of aldose reductase is briefly discussed along with their prospective applications in other afflictions.

Correlation between parents and child’s version of the child health survey for asthma questionnaire

Background

The American Academy of Pediatrics Children's Health Survey for Asthma (CHSA) is a widely used instrument to assess various aspects of health and well-being in relation to asthma. There is a parent and a child version of this questionnaire and little is known about the concordance between these versions.

Method

In a cross-sectional study conducted in 13 facilities, hospitals and outpatient clinics covering all areas of Kosovo, children with asthma aged 7-16 years were enrolled. Information about asthma diagnosis was obtained from the treating physician. Children and parents answered the CHSA, parent or child version (CHSA-C) as well as a number of questions about environmental conditions, health insurance and socio-demographic characteristics.

Results

The survey included 161 Kosovar children with asthma and their caregivers. Although there were significant differences between parents and child versions regarding physical health, child activity and emotional health, with parents rating physical and emotional health higher and child activity lower, there were significant correlations (R > 0.7) for physical and child activity scales but only a low one (R = 0.25) for emotional health. Inspection of concordance for single items revealed very high correlations (>0.9) for all disease events, but a significant underestimation of the number of wheezing episodes by parents. Good agreement was found for statements about disease severity.

Conclusions

The high correlation between information about children's health obtained from parents and children underlines the usefulness of parents as source of information on child's asthma. Impact of the disease on emotional health is, however, underestimated by parents.

Synthesis and spectroscopic study of novel mixed ligand formula "Artemisinin/Zn" and assessment of its inhibitory effect against "SARS-CoV-2″

Background

Herein, a newly synthesised mixed ligand artemisinin/zinc (Art/Zn) is chemically characterised and examined against SARS-CoV-2.

Methods

The synthesised complex was thoroughly characterised using various spectroscopic methods (FT-IR, UV and XRD). Its surface morphology and chemical purity were investigated using transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analysis. The synthesised Art/Zn complex was tested for its inhibitory effects against SARS-CoV-2 using inhibitory concentration 50 (IC₅₀) and cytotoxicity concentration 50 (CC₅₀).

Results

The results reveal that the Art/Zn complex exhibits a moderate in vitro inhibitory effects against SARS-CoV-2, with a CC₅₀ index of 213.6 μg/ml and an IC50 index of 66.79 μg/ml. Notably, it exhibits the inhibitory effect (IC₅₀ = 66.79 μg/ml) at a very low concentration without any observable cytotoxic effects on host cells (CC₅₀ = 213.6 μg/ml). Its mode of action against SARS-CoV-2 involves inhibiting the viral replication. The predicted target classes that Art/Zn may affect include kinases, which can regulate and inhibit the viral replication and binding to the angiotensin-converting enzyme-2 (ACE2) receptor and the main protease inhibitor (M^Pro), thereby inhibiting the activity of SARS-CoV-2 and proved by the molecular dynamics simulation.

Conclusion

We recommend using the Art/Zn complex owing to its moderate inhibitory and antiviral effects against the SARS-CoV-2 with a low cytotoxic effect on host (Vero E6) cells. We suggest conducting further prospective studies to investigate the biological effects of Art/Zn in animal models at different concentrations for testing its clinical efficacy and safety in inhibiting SARS-CoV-2 activities.

Environmental risks and sphingolipid signatures in adult asthma and its phenotypic clusters: a multicentre study

BACKGROUND

Adult asthma is phenotypically heterogeneous with unclear aetiology. We aimed to evaluate the potential contribution of environmental exposure and its ensuing response to asthma and its heterogeneity.

METHODS

Environmental risk was evaluated by assessing the records of National Health Insurance Research Database (NHIRD) and residence-based air pollution (particulate matter with diameter less than 2.5 micrometers (PM_2.5) and PM_2.5-bound polycyclic aromatic hydrocarbons (PAHs)), integrating biomonitoring analysis of environmental pollutants, inflammatory markers and sphingolipid metabolites in case-control populations with mass spectrometry and ELISA. Phenotypic clustering was evaluated by t-distributed stochastic neighbor embedding (t-SNE) integrating 18 clinical and demographic variables.

FINDINGS

In the NHIRD dataset, modest increase in the relative risk with time-lag effect for emergency (N=209 837) and outpatient visits (N=638 538) was observed with increasing levels of PM_2.5 and PAHs. Biomonitoring analysis revealed a panel of metals and organic pollutants, particularly metal Ni and PAH, posing a significant risk for current asthma (ORs=1.28-3.48) and its severity, correlating with the level of oxidative stress markers, notably Nε-(hexanoyl)-lysine (r=0.108-0.311, p<0.05), but not with the accumulated levels of PM_2.5 exposure. Further, levels of circulating sphingosine-1-phosphate and ceramide-1-phosphate were found to discriminate asthma (p<0.001 and p<0.05, respectively), correlating with the levels of PAH (r=0.196, p<0.01) and metal exposure (r=0.202-0.323, p<0.05), respectively, and both correlating with circulating inflammatory markers (r=0.186-0.427, p<0.01). Analysis of six phenotypic clusters and those cases with comorbid type 2 diabetes mellitus (T2DM) revealed cluster-selective environmental risks and biosignatures.

INTERPRETATION

These results suggest the potential contribution of environmental factors from multiple sources, their ensuing oxidative stress and sphingolipid remodeling to adult asthma and its phenotypic heterogeneity.

LC-MS-based metabolomics reveals the in vivo effect of Shegan Mahuang Decoction in an OVA-induced rat model of airway hyperresponsiveness

The traditional Chinese medicine (TCM) formula Shegan Mahuang Decoction (SMD) has been used for treating asthma with significant clinical efficacy, but its mechanism of action has not been well investigated. This study aimed to investigate the anti-asthma effects of SMD on ovalbumin (OVA)-induced airway hyperresponsiveness (AHR) in rats and its potential mechanisms using liquid chromatography-mass spectrometry (LC-MS)-based metabolomics combined with Gene Expression Omnibus (GEO) data mining. The results showed that the administration of SMD significantly attenuated OVA-induced lung histopathological changes. OVA-induced elevation of the immunoglobulin (IgE) and interleukin-4 (IL-4) levels was also inhibited by SMD. A total of 28 significantly changed metabolites in plasma were selected from metabolomics analysis. After treatment with SMD, 24 of them were negatively regulated and the related metabolisms were involved in multiple metabolic pathways such as sphingolipid metabolism and arachidonic acid metabolism. The differentially expressed genes (DEGs) were obtained by GEO data mining. The integrated pathway analysis highlighted 11 signaling pathways that were associated with the anti-asthma effect of SMD. Among them, the metabolite-gene-pathway network showed that the peroxisome proliferator-activated receptors (PPAR) signaling pathway might be the most significant one. This study revealed that SMD exerted an anti-asthma effect against OVA-induced AHR via comprehensively modulating the sphingolipid metabolism, arachidonic acid metabolism, and PPAR signaling, which indicated the synergistic effect of multi-component, multi-target, and multi-pathway of TCM in the treatment of the disease. This study expands our understanding of SMD in the treatment of asthma from a metabolomics perspective.

Circulating MicroRNAs Expression Profile in Lung Inflammation: A Preliminary Study

Background: Bronchial asthma is an inflammatory airway disease with an ever-increasing incidence. Therefore, innovative management strategies are urgently needed. MicroRNAs are small molecules that play a key role in lungs cellular functions and are involved in chronic inflammatory diseases, such as bronchial asthma. This study aims to compare microRNA serum expression between subjects with asthma, obesity, the most common co-morbidity in asthma, and healthy controls to obtain a specific expression profile specifically related to lung inflammation. Methods: We collected serum samples from a prospective cohort of 25 sex-matched subjects to determine circulating miRNAs through a quantitative RT-PCR. Moreover, we performed an in silico prediction of microRNA target genes linked to lung inflammation. Results: Asthmatic patients had a significant lower expression of hsa-miR-34a-5p, 181a-5p and 146a-5p compared to both obese and healthy ones suggesting microRNAs’ specific involvement in the regulation of lungs inflammatory response. Indeed, using in silico analysis, we identified microRNAs novel target genes as GATA family, linked to the inflammatory-related pathway. Conclusions: This study identifies a novel circulating miRNAs expression profile with promising potentials for asthma clinical evaluations and management. Further and larger investigations will be needed to confirm the potential role of microRNA as a clinical marker of bronchial asthma and eventually of pharmacological treatment response.

Impact of cytokines genes polymorphisms and their serum levels on childhood asthma in Egyptian population

BACKGROUND

Asthma is chronic immune-mediated airway inflammation, and it is affected by a complex network of interacting cytokines. To date, the exact role of each cytokine and its genetic polymorphisms in childhood asthma development and its severity has remained poorly understood. The purpose of this study was to explore potential roles of four cytokine genes polymorphism and serum levels l [(T helper-2 (Th2) cytokine); Interleukin-4 (IL-4) 590, (Th3 cytokine); and transforming growth factor β1 (TGF-β1) 509T; (Th17) including tumor necrosis factor-alpha (TNF-α), and IL17A rs8193036] in childhood asthma risk and control in Egyptian children, for the 1st time.

MATERIALS AND METHODS

This case-control study included two children subgroups; Group1 included 216 non-asthmatic controls and (Group 2) 216 cases diagnosed with asthma (clinically and spirometry-based) were classified as controlled, partly controlled, and uncontrolled. Polymorphisms of TGF-β1-509, IL-4 590, and TNF-α-308 genes were detected using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). IL-17 was genotyped using tetra-primer amplification refractory mutation system polymerase chain reaction (ARMS-PCR). Serum cytokines levels were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Serum total IgE, TGF-β1, IL4, TNF-α, and IL17A levels were significantly higher in asthmatic compared to controls. Also, significant increases in serum total IgE, IL-4, TGF-β1, and TNF-α levels are combined with poor asthma control, while no significant IL17A changes. There were significant changes of IL-4-590, TNF-α-308, and IL17A genotypes and allele distributions between asthmatic and controls groups as well as different asthma control levels; while no impact of TGF-β1 SNP on asthma risk and control level. Four cytokines SNPs affected their serum levels among asthmatic patients.

CONCLUSION

There are impacts of cytokine gene polymorphisms (IL-4-590, TNF-α-308, and IL17A); but not TGF-β1 on asthma susceptibility and poor asthma control in Egyptian children.

Natural therapeutics and nutraceuticals for lung diseases: Traditional significance, phytochemistry, and pharmacology

BACKGROUND

Lung diseases including chronic obstructive pulmonary disease (COPD), infections like influenza, acute respiratory distress syndrome (ARDS), asthma and pneumonia lung cancer (LC) are common causes of sickness and death worldwide due to their remoteness, cold and harsh climatic conditions, and inaccessible health care facilities.

PURPOSE

Many drugs have already been proposed for the treatment of lung diseases. Few of them are in clinical trials and have the potential to cure infectious diseases. Plant extracts or herbal products have been extensively used as Traditional Chinese Medicine (TCM) and Indian Ayurveda. Moreover, it has been involved in the inhibition of certain genes/protiens effects to promote regulation of signaling pathways. Natural remedies have been scientifically proven with remarkable bioactivities and are considered a cheap and safe source for lung disease.

METHODS

This comprehensive review highlighted the literature about traditional plants and their metabolites with their applications for the treatment of lung diseases through experimental models in humans. Natural drugs information and mode of mechanism have been studied through the literature retrieved by Google Scholar, ScienceDirect, SciFinder, Scopus and Medline PubMed resources against lung diseases.

RESULTS

In vitro, in vivo and computational studies have been explained for natural metabolites derived from plants (like flavonoids, alkaloids, and terpenoids) against different types of lung diseases. Probiotics have also been biologically active therapeutics against cancer, anti-inflammation, antiplatelet, antiviral, and antioxidants associated with lung diseases.

CONCLUSION

The results of the mentioned natural metabolites repurposed for different lung diseases especially for SARS-CoV-2 should be evaluated more by advance computational applications, experimental models in the biological system, also need to be validated by clinical trials so that we may be able to retrieve potential drugs for most challenging lung diseases especially SARS-CoV-2.

α4β1 and αMβ2 Integrin Expression and Pro-Proliferative Properties of Eosinophil Subtypes in Asthma

Eosinophilic inflammation is one of the main pathophysiological features in asthma. Two subtypes of eosinophils exist in the lung and systemic circulation: lung-resident eosinophils (rEOS) and inflammatory eosinophils (iEOS). We evaluated the expression of α₄β₁ and α_Mβ₂ integrins of eosinophil subtypes and their influence on airway smooth muscle (ASM) cell proliferation and viability in asthma. We included 16 severe non-allergic eosinophilic asthma (SNEA) patients, 13 steroid-free, non-severe allergic asthma (AA) patients, and 12 healthy control subjects (HS). For AA patients, a bronchial allergen challenge with Dermatophagoides pteronyssinus was performed. The eosinophil subtypes were distinguished using magnetic bead-labeled antibodies against surface CD62L, and individual combined cell cultures were prepared with ASM cells. The integrins gene expression was analyzed by a quantitative real-time polymerase chain reaction. Proliferation was assessed by the Alamar blue assay, and viability by annexin V and propidium iodide staining. rEOS-like cells were characterized by the relatively higher gene expression of the β₁ integrin subunit, whereas iEOS-like cells were characterized by the α_M and β₂ integrin subunits. The inclusion of either eosinophil subtypes in co-culture significantly increased the proliferation of ASM cells, and the effect of rEOS-like cells was stronger than iEOS-like cells (p < 0.05). Furthermore, rEOS-like cells had a more pronounced effect on reducing ASM cell apoptosis compared to that of iEOS-like cells (p < 0.05). Lastly, the bronchial allergen challenge significantly enhanced only the iEOS-like cells’ effect on ASM cell proliferation and viability in AA patients (p < 0.05). These findings highlight the different expression of α₄β₁ and α_Mβ₂ integrins on distinct eosinophil subtypes in asthma. Therefore, rEOS-like cells have a stronger effect in stimulating ASM cell proliferation and viability; however, contact with specific allergens mainly enhances pro-proliferative iEOS-like cell properties.

Lippia javanica (Zumbani) herbal tea infusion attenuates allergic airway inflammation via inhibition of Th2 cell activation and suppression of oxidative stress

BACKGROUND

Lippia javanica (lemon bush) is commonly used in the treatment of respiratory ailments, including asthma in southern African countries but there is no scientific evidence to support this claim. This study investigated the anti-inflammatory, antioxidant and anti-asthmatic effects of L. javanica using a rat model of asthma.

METHODS

A 5% w/v L. javanica tea infusion was prepared and characterised by liquid chromatography-mass spectrometer (LC-MS). Animals were intraperitoneally sensitized with ovalbumin (OVA) and subsequently challenged intranasal with OVA on day 15 except the control group. Animals were grouped (n = 5/group) for treatment: unsensitised control, sensitised control, sensitised + prednisolone and sensitised + L. javanica at 50 mg/kg/day and 100 mg/kg/day - equivalent to 1 and 2 cups of tea per day, respectively. After 2 weeks of treatment, bronchoalveolar lavage fluid (BALF) was collected for total and differential white blood cell (WBC) count. Nitric oxide (NO), lipid peroxidation and antioxidants were also assessed in BALF. Ovalbumin specific IgE antibody and inflammatory cytokines: IL-4, IL-5, IL-13 and TNF-alpha were measured in serum. Lung and muscle tissues were histological examined.

RESULTS

L. javanica was rich in phenolic compounds. OVA sensitisation resulted in development of allergic asthma in rats. L. javanica treatment resulted in a reduction in total WBC count as well as eosinophils, lymphocytes and neutrophils in BALF. L. javanica inhibited Th2-mediated immune response, which was evident by a decrease in serum IgE and inflammatory cytokines: IL-4, IL-5, IL-13 and TNF-α. L. javanica treatment also reduced malondialdehyde (MDA) and NO, and increased superoxide dismutase, glutathione and total antioxidant capacity. Histology showed significant attenuation of lung infiltration of inflammatory cells, alveolar thickening, and bronchiole smooth muscle thickening.

CONCLUSION

L. javanica suppressed allergic airway inflammation by reducing Th2-mediated immune response and oxidative stress in OVA-sensitized rats which may be attributed to the presence of phenolic compound in the plant. This finding validates the traditional use of L. javanica in the treatment of respiratory disorders.

Biological effect of PM10 on airway epithelium-focus on obstructive lung diseases

Recently, a continuous increase in environmental pollution has been observed. Despite wide-scale efforts to reduce air pollutant emissions, the problem is still relevant. Exposure to elevated levels of airborne particles increased the incidence of respiratory diseases. PM₁₀ constitute the largest fraction of air pollutants, containing particles with a diameter of less than 10 μm, metals, pollens, mineral dust and remnant material from anthropogenic activity. The natural airway defensive mechanisms against inhaled material, such as mucus layer, ciliary clearance and macrophage phagocytic activity, may be insufficient for proper respiratory function. The epithelium layer can be disrupted by ongoing oxidative stress and inflammatory processes induced by exposure to large amounts of inhaled particles as well as promote the development and exacerbation of obstructive lung diseases. This review draws attention to the current state of knowledge about the physical features of PM₁₀ and its impact on airway epithelial cells, and obstructive pulmonary diseases.

Changes in Serum MicroRNAs after Anti-IL-5 Biological Treatment of Severe Asthma

There is currently enough evidence to think that miRNAs play a role in several key points in asthma, including diagnosis, severity of the disease, and response to treatment. Cells release different types of lipid double-membrane vesicles into the extracellular microenvironment, including exosomes, which function as very important elements in intercellular communication. They are capable of distributing genetic material, mRNA, mitochondrial DNA, and microRNAs (miRNAs). Serum miRNA screening was performed in order to analyze possible changes in serum miRNAs in 10 patients treated with reslizumab and 6 patients with mepolizumab after 8 weeks of treatment. The expression of miR-338-3p was altered after treatment (p < 0.05), although no significant differences between reslizumab and mepolizumab were found. Bioinformatic analysis showed that miR-338-3p regulates important pathways in asthma, such as the MAPK and TGF-β signaling pathways and the biosynthesis/degradation of glucans (p < 0.05). However, it did not correlate with an improvement in lung function. MiRNA-338-3p could be used as a biomarker of early response to reslizumab and mepolizumab in severe eosinophilic asthmatic patients. In fact, this miRNA could be involved in airway remodeling, targeting genes related to MAPK and TGF-β signaling pathways.

Interleukin-10 Gene Promoter Polymorphisms and Susceptibility to Asthma: Systematic Review and Meta-analysis

Several studies have previously assessed the association between interleukin (IL)-10 gene polymorphisms and the risk of asthma, leading to conflicting results. To resolve the incongruent outcomes yielded from different single studies, we conducted the most up-to-date meta-analysis of the IL-10 gene rs1800896, rs1800871, and rs1800872 single-nucleotide polymorphisms (SNPs) and susceptibility to asthma. A systematic literature search performed until April 2020, and the pooled odds ratio (OR) and their corresponding 95% confidence interval (CI) were calculated to determine the association strength. Thirty articles comprising 5678 asthmatic patients and 6079 controls met the inclusion criteria. No significant association was found between rs1800872 SNP and susceptibility to asthma across all genetic models in the overall and subgroup analyses. The rs1800871 SNP had only significant association with a decreased risk of asthma in Europeans (OR 0.66, CI 0.53-0.82, P < 0.001). However, rs1800896 SNP was significantly associated with a decreased risk of asthma by dominant (OR 0.67, CI 0.50-0.90, P < 0.001) and heterozygote (OR 0.66, CI 0.49-0.88, P < 0.001) models in the overall analysis. Subgroup analyses indicated significant association of rs1800896 SNP by dominant (OR 0.45, CI 0.28-0.72, P < 0.001) and heterozygote (OR 0.43, CI 0.26-0.70, P < 0.001) models in the African population. The IL-10 rs1800896 SNP confers protection against the risk of asthma, especially in Africans. Additionally, rs1800871 SNP has a protective role against asthma in Europeans.

Burden and impact of arrhythmias in asthma-related hospitalizations: Insight from the national inpatient sample

BACKGROUND

This study aimed to analyze the burden and impact of cardiac arrhythmias in adult patients hospitalized with asthma exacerbation using the nationwide inpatient database.

METHODS

We used the National Inpatient Sample (NIS) database (2010-2014) to identify arrhythmias in asthma-related hospitalization and its impact on inpatient mortality, hospital length of stay (LOS), and hospitalization charges. We also used multivariable analysis to identify predictors of in-hospital arrhythmia and mortality.

RESULTS

We identified 12,988,129 patients hospitalized with primary diagnosis of asthma; among them, 2,014,459(16%) patients had cardiac arrhythmia. The most frequent arrhythmia identified is atrial fibrillation (AFib) (8.95%). The AFib and non-AFib arrhythmia group had higher mortality (3.40% & 2.22% vs 0.74%), mean length of stay (LOS) (5.9 & 5.4 vs 4.2 days), and hospital charges ($53,172 & $51,105 vs $34,585) as compared to the non-arrhythmia group (P < .005). Predictors of arrhythmia in asthma-related hospitalization were history of PCI or CABG, valvular heart disease, congestive heart failure (CHF), and acute respiratory failure. Predictors of higher mortality in arrhythmia group were acute respiratory failure, sepsis, and acute myocardial infarction.

CONCLUSIONS

Around 16% of adult patients hospitalized with asthma exacerbation experience arrythmia (mostly AFib 8.95%). The presence of arrhythmias was associated with higher in-hospital mortality, LOS, and hospital charges in hospitalized asthmatics.

The Anti-inflammatory Potential of Selected Plant-derived Compounds in Respiratory Diseases

Inflammation plays a major role in chronic airway diseases like asthma, COPD, and cystic fibrosis. Inflammation plays a crucial role in the worsening of the lung function resulting in worsening symptoms. The inflammatory process is very complexed, therefore the strategies for developing an effective treatment for inflammatory airway diseases would benefit from the use of natural substances. Plant products have demonstrated anti-inflammatory properties on various lung disease models and numerous natural plant agents have successfully been used to treat inflammation. Naturally occurring substances may exert some anti-inflammatory effects by modulating some of the inflammatory pathways. These agents have been used in different cultures for thousands of years and have proven to be relatively safe. Parthenolide, apocynin, proanthocyanidins, and boswellic acid present different mechanisms of actions - among others, through NF-kB or NADPH oxidase inhibition, therefore showing a wide range of applications in various inflammatory diseases. Moreover, some of them have also antioxidant properties. This review provides an overview of the anti-inflammatory effects of some of the natural agents and illustrates their great potential as sources of drugs to cover an extensive range of pharmacological effects.

Role of microRNA-21 and microRNA-155 as biomarkers for bronchial asthma

MicroRNA (miRNA)-21 and miRNA-155 are important regulators of gene expression of different immunological molecules. This study aimed to investigate the role of miRNA-21 and miRNA-155 as biomarkers in asthma by comparing their serum expression levels in asthmatic patients to those in healthy controls and correlating their levels with serum IL-4. The expression levels of miRNA-21 and miRNA-155 were evaluated by quantitative RT-PCR. Serum levels of IL-4 were determined using ELISA. Asthmatic patients showed significantly higher serum miRNA-21 and miRNA-155 expression levels compared to controls. A statistically significant positive correlation between the expression levels of miRNA-21 and IL-4 serum levels in asthmatic patients was detected. Nonetheless, no correlation was detected between miRNA-155 expression and each of IL-4 and miRNA-21. A receiver operating characteristic curve analysis showed that at a cut-off value of 1.37, the sensitivity of miRNA-21 as an asthma biomarker was 100% and the specificity was 95%. At a cut-off value of 1.96, the sensitivity of miRNA-155 as an asthma biomarker was 100% and the specificity was 100%. It can be concluded that miRNA-21 and miRNA-155 are potential non-invasive biomarkers in the diagnosis of eosinophilic asthma and its response to therapy.

Exposure to Polyhexamethylene Guanidine Exacerbates Bronchial Hyperresponsiveness and Lung Inflammation in a Mouse Model of Ovalbumin-Induced Asthma

Humidifier disinfectants (HDs) exposure has now been associated with acute lung injury and pulmonary fibrosis; polyhexamethylene guanidine (PHMG) has been confirmed to cause severe lung inflammation and fibrosis in mice. Recent evidence also indicates that HDs exposure increases the asthma risk in children, but the underlying mechanisms remain unclear. We aimed to investigate the effects of PHMG exposure on asthma in mice and the potential underlying mechanisms. BALB/c mice were intranasally administered PHMG (0.1 mg/kg/day; 5 days per week) during 2 episodes of ovalbumin (OVA) sensitization and were then challenged with 1% OVA by inhalation. Bronchial hyperresponsiveness (BHR), inflammatory cell influx into bronchoalveolar lavage (BAL) fluid, serum total and OVA-specific immunoglobulin (Ig) E levels, and histopathological changes in the lung were analyzed. The levels of asthma-related cytokines and chemokines were assayed in the lung tissues to evaluate possible mechanisms. Exposure to PHMG following OVA sensitization and challenge significantly enhanced BHR, inflammatory cell counts in BAL fluid, airway inflammation, and total serum IgE levels in the asthma mouse model. In addition, the levels of chemokine ligand (CCL) 11 and serpine F1/pigment epithelium-derived factor (SERPINF1) were significantly elevated in the lungs of these mice compared to those in the control and OVA-treated only groups. Our findings suggest that PHMG can enhance the development of allergic responses and lung inflammation via CCL11- and SERPINF1-induced signaling in a mouse model of asthma.

Lactic Acid Bacteria Ameliorate Diesel Exhaust Particulate Matter-Exacerbated Allergic Inflammation in a Murine Model of Asthma

Several air pollution components such as sulfur dioxide, ozone, nitrogen dioxide, and diesel exhaust particulate matter (DEPM) have been linked to the development of asthma. In this study, we investigated the therapeutic potential of three lactic acid bacteria species, Lactobacillus plantarum GREEN CROSS Wellbeing (GCWB)1001, Pediococcus acidilactici GCWB1085, and Lactobacillus rhamnosus GCWB1156, in preventing DEPM-exacerbated asthma in mice. BALB/c mice were first sensitized with ovalbumin (OVA) and were either challenged with OVA or DEPM (DEPM-exacerbated asthma model) by intranasal instillation. All three strains showed no hemolytic activity, suggesting a good safety profile. Oral administration of lactic acid bacteria reduced OVA + DEPM-induced inflammatory infiltration, goblet cell hyperplasia, airway remodeling, and the levels of proinflammatory cytokines and chemokines in bronchoalveolar lavage fluid (BALF). The probiotics also attenuated OVA + DEPM-induced immunoglobulin E (IgE) levels in serum and in BALF, and significantly reduced caspase-3 activity, total collagen level, and matrix metalloproteinase (MMP)-9 activity. In conclusion, lactic acid bacteria such as L. plantarum GCWB1001, P. acidilactici GCWB1085, and L. rhamnosus treatment in mice with asthma showed significant efficacy in preventing lung inflammation exacerbated by DEPM administration.

Chronic Airway Allergy Induces Pro-Inflammatory Responses in the Brain of Wildtype Mice but Not 3xTgAD Mice

The effects of systemic inflammation on the pathogenesis of Alzheimer's disease (AD) are not clarified, both beneficial and deleterious effects being reported. Allergy is accompanied by a systemic inflammatory response and some epidemiological studies have reported a positive association between a history of allergy/asthma and dementia. To investigate whether chronic airway allergy influences the inflammatory status in the brain, AD-like pathology, and behaviour in relation to AD, we induced chronic airway allergy in triple transgenic AD (3xTgAD) and wildtype (WT) mice by repeated exposure to ovalbumin (OVA) as allergen. Behavioural tests relevant for hippocampus-dependent behaviour were performed. We found that allergy significantly increased the brain levels of immunoglobulin (Ig) G, IgE. In 3xTgAD mice, allergy increased the levels of decay accelerating factor and decreased the phosphorylation of p38. In contrast, allergy increased the levels of interleukin (IL)-1β and complement component 1q (C1q) in WT mice. Bronchoalveolar lavage fluid analysis confirmed eosinophilia in both genotypes, but the basal levels of eosinophils were lower in 3xTgAD mice. In summary, allergy induced predominantly anti-inflammatory effects in 3xTgAD mice, and pro-inflammatory effects in WT mice, thus being another potential factor to be considered when studying AD pathogenesis.

KLF2 regulates neutrophil migration by modulating CXCR1 and CXCR2 in asthma

Neutrophils are key inflammatory cells in the immunopathogenesis of asthma. Neutrophil migration can be initiated through activation of the CXCR1 and CXCR2 receptors by CXC chemokines, such as IL-8. Although transcription factor KLF2 has been found to maintain T cell migration patterns through repression of several chemokine receptors, whether KLF2 can regulate neutrophil migration via modulation of CXCR1 and CXCR2 is unknown. Here, we aimed to explore the functions of KLF2, CXCR1 and CXCR2 in neutrophil migration in asthma and to establish a regulatory role of KLF2 for CXCR1/2. We demonstrate that with asthma aggravation, the percentages and migration rates of peripheral blood neutrophils gradually increased in asthmatic patients and the guinea pig asthma model. Correspondingly, both the KLF2 mRNA and protein levels in neutrophils were gradually reduced. While CXCR1 and CXCR2 expression was negatively correlated with KLF2. In vitro knockdown of KLF2 dramatically increased the migration of HL-60-drived neutrophil-like cells, which was accompanied by an increase in the CXCR1 and CXCR2 mRNA and protein expression levels. Taken together, our results indicate that decreased KLF2 aggravates asthma progression by promoting neutrophil migration, which is associated with the transcriptional upregulation of CXCR1 and CXCR2. The KLF2 and/or CXCR1/2 expression levels may represent an indicator of asthma severity.

Mediation of Firearm Violence and Preterm Birth by Pregnancy Complications and Health Behaviors: Addressing Structural and Postexposure Confounding

Firearm violence may indirectly affect health among pregnant women living in neighborhoods where it is endemic. We used birth, death, emergency department, and hospitalization data from California from 2007-2011 to estimate the association between living in a neighborhood with high firearm violence and preterm delivery, and assessed whether there was mediation by diagnoses of pregnancy complications and health behaviors during pregnancy. We used an ensemble machine learning algorithm to predict the propensity for neighborhoods to be classified as having a high level of firearm violence. Risk differences for the total effect and stochastic direct and indirect effects were estimated using targeted maximum likelihood. Residence in high-violence neighborhoods was associated with higher prevalence of preterm birth (risk difference (RD) = 0.46, 95% confidence interval (CI): 0.13, 0.80), infections (RD = 1.34, 95% CI: -0.17, 2.86), asthma (RD = 0.76, 95% CI: 0.03, 1.48), and substance use (RD = 0.74, 95% CI: 0.00, 1.47). The largest indirect effects for the association between violence and preterm birth were observed for infection (stochastic indirect effect = 0.04, 95% CI: 0.00, 0.08) and substance use (stochastic indirect effect = 0.04, 95% CI: 0.01, 0.06). Firearm violence was associated with risk of preterm delivery, and this association was partially mediated by infection and substance use.

Effects of VAChT reduction and α7nAChR stimulation by PNU-282987 in lung inflammation in a model of chronic allergic airway inflammation

The cholinergic anti-inflammatory pathway has been shown to regulate lung inflammation and cytokine release in acute models of inflammation, mainly via α7 nicotinic receptor (α7nAChR). We aimed to evaluate the role of endogenous acetylcholine in chronic allergic airway inflammation in mice and the effects of therapeutic nAChR stimulation in this model. We first evaluated lung inflammation and remodeling on knock-down mice with 65% of vesicular acetylcholine transport (VAChT) gene reduction (KDVAChT) and wild-type(WT) controls that were subcutaneously sensitized and then inhaled with ovalbumin(OVA). We then evaluated the effects of PNU-282987(0.5-to-2mg/kg),(α7nAChR agonist) treatment in BALB/c male mice intraperitoneal sensitized and then inhaled with OVA. Another OVA-sensitized-group was treated with PNU-282987 plus Methyllycaconitine (MLA,1 mg/kg, α7nAChR antagonist) to confirm that the effects observed by PNU were due to α7nAChR. We showed that KDVAChT-OVA mice exhibit exacerbated airway inflammation when compared to WT-OVA mice. In BALB/c, PNU-282987 treatment reduced the number of eosinophils in the blood, BAL fluid, and around airways, and also decreased pulmonary levels of IL-4,IL-13,IL-17, and IgE in the serum of OVA-exposed mice. MLA pre-treatment abolished all the effects of PNU-282987. Additionally, we showed that PNU-282987 inhibited STAT3-phosphorylation and reduced SOCS3 expression in the lung. These data indicate that endogenous cholinergic tone is important to control allergic airway inflammation in a murine model. Moreover, α7nAChR is involved in the control of eosinophilic inflammation and airway remodeling, possibly via inhibition of STAT3/SOCS3 pathways. Together these data suggest that cholinergic anti-inflammatory system mainly α7nAChR should be further considered as a therapeutic target in asthma.

The presence of Aspergillus fumigatus in asthmatic airways is not clearly related to clinical disease severity

BACKGROUND

It is suggested that airway fungi, in particular Aspergillus may impinge on clinical phenotype in asthma. Indeed, the term severe asthma with fungal sensitization (SAFS) has been coined. We aimed to ascertain whether the presence of fungi, in particular Aspergillus fumigatus, in the airway correlated with asthma severity and control. Furthermore, we aimed to determine whether traditional markers of Aspergillus sensitization related to the presence of Aspergillus within the airway.

METHODS

Sixty-nine patients characterized by asthma severity (GINA) and level of control (ACQ-7) underwent bronchoscopy and bronchoalveolar lavage (BAL). Serum was assessed for A fumigatus-specific IgE and total IgE. Galactomannan and relevant cytokine levels were assessed in serum, plasma and BAL. BAL was analyzed for the presence of A fumigatus.

RESULTS

In BAL, fungi were visible by microscopy in 70% and present by qPCR in 86% of patients, while A fumigatus was detectable by qPCR in 46%. Plasma and BAL IL-4, IL-6, IL-10, IL-13 and TNF-α correlated with BAL fungal presence, while plasma IL-17 correlated with BAL fungal presence. Aspergillus positive BAL correlated with increased plasma and BAL IL-6 and BAL IL-13. There was no relationship between fungal airway presence and steroid dose, asthma severity or control. The presence of Aspergillus within the airway did not relate to serum IgE positivity for Aspergillus.

CONCLUSIONS

Fungi were present in a large proportion of our asthmatic patients' airways, but their presence was not predicted by traditional markers of sensitization, nor did it appear to be related to measures of disease severity or control.

The importance of caveolins and caveolae to dermatology: Lessons from the caves and beyond

Caveolae are flask-shaped invaginations of the cell membrane rich in cholesterol and sphingomyelin, with caveolin proteins acting as their primary structural components that allow compartmentalization and orchestration of various signalling molecules. In this review, we discuss how pleiotropic functions of caveolin-1 (Cav1) and its intricate roles in numerous cellular functions including lipid trafficking, signalling, cell migration and proliferation, as well as cellular senescence, infection and inflammation, are integral for normal development and functioning of skin and its appendages. We then examine how disruption of the homeostatic levels of Cav1 can lead to development of various cutaneous pathophysiologies including skin cancers, cutaneous fibroses, psoriasis, alopecia, age-related changes in skin and aberrant wound healing and propose how levels of Cav1 may have theragnostic value in skin physiology/pathophysiology.

The comparison of fluticasone propionate/formoterol with fluticasone propionate/salmeterol for paediatric asthma: a meta-analysis of randomized controlled trials

Introduction

The comparison of fluticasone propionate/formoterol (FP/FORM) with fluticasone propionate/salmeterol (FP/SAL) for paediatric asthma remains controversial.

Aim

We conduct a systematic review and meta-analysis to explore the efficacy and safety of FP/FORM versus FP/SAL for paediatric asthma.

Material and methods

We have searched PubMed, Embase, Web of science, EBSCO, and Cochrane library databases through August 2019 for randomized controlled trials (RCTs) assessing the effect of FP/FORM versus FP/SAL for paediatric asthma. This meta-analysis is performed using the random-effects model.

Results

Three RCTs are included in the meta-analysis. Overall for paediatric asthma, FP/FORM and FP/SAL demonstrate a comparable influence on FEVj (Std. MD = -0.01; 95% CI: -0.04 to 0.03; p = 0.62), FVC (Std. MD = 0; 95% CI: -0.07 to 0.06; p = 0.87), FEF25 (Std. MD = -1.69; 95% CI: -6.69 to 3.31; p = 0.51), FEF50 (Std. MD = 0.10; 95% CI: -0.12 to 0.33; p = 0.37), FEF75 (Std. MD = 0.01; 95% CI: -0.21 to 0.24; p = 0.91), asthma symptom scores (Std. MD = -0.03; 95% CI: -0.11 to 0.04; p = 0.43), sleep disturbance scores (Std. MD = 0.03; 95% CI: -0.19 to 0.24; p = 0.81) and adverse events (RR = 1.07; 95% CI: 0.83 to 1.38; p = 0.61).

Conclusions

FP/FORM and FP/SAL show a comparable efficacy for paediatric asthma.

Diesel exhaust particle and dust mite induced airway inflammation is modified by cerium dioxide nanoparticles

Cerium dioxide nanoparticles (CeO₂NPs) have been used as diesel fuel-borne catalysts for improved efficiency and pollutant emissions. Concerns that such material may influence diesel exhaust particle (DEP) effects within the lung upon inhalation, prompted us to examine particle responses in mice in the presence and absence of the common allergen house dust mite (HDM). Repeated intranasal instillation of combined HDM and DEP increased airway mucin, eosinophils, lymphocytes, IL-5, IL-13, IL-17A and plasma IgE, which were further increased with CeO₂NPs co-exposure. A single co-exposure of CeO₂NPs and DEP after repeated HDM exposure increased macrophage and IL-17A levels above DEP induced levels. CeO₂NPs exposure in the absence of HDM also resulted in increased levels of plasma IgE and airway mucin staining, changes not observed with repeated DEP exposure alone. These observations indicate that CeO₂NPs can modify exhaust particulate and allergen induced inflammatory events in the lung with the potential to influence conditions such as allergic airway disease.

Protein Misfolding and Endoplasmic Reticulum Stress in Chronic Lung Disease: Will Cell-Specific Targeting Be the Key to the Cure?

Chronic lung disease accounts for a significant global burden with respect to death, disability, and health-care costs. Due to the heterogeneous nature and limited treatment options for these diseases, it is imperative that the cellular and molecular mechanisms underlying the disease pathophysiology are further understood. The lung is a complex organ with a diverse cell population, and each cell type will likely have different roles in disease initiation, progression, and resolution. The effectiveness of a given therapeutic agent may depend on the net effect on each of these cell types. Over the past decade, it has been established that endoplasmic reticulum stress and the unfolded protein response are involved in the development of several chronic lung diseases. These conserved cellular pathways are important for maintaining cellular proteostasis, but their aberrant activation can result in pathology. This review discusses the current understanding of endoplasmic reticulum stress and the unfolded protein response at the cellular level in the development and progression of various chronic lung diseases. We highlight the need for increased understanding of the specific cellular contributions of unfolded protein response activation to these pathologies and suggest that the development of cell-specific targeted therapies is likely required to further decrease disease progression and to promote resolution of chronic lung disease.

Awareness and Current Therapeutics of Asthma

Introduction:

Asthma is a serious allergic disorder of the respiratory system. It affects about 300 million people worldwide. This has a great burden on medical treatment. Several medicines are available, but they have many serious side effects. Therefore, there is a need to search for a new therapeutic agent with no or minimal side effects while most economical for patients. In folk medicine, antiasthmatics herbal medicine has been used and showed potential therapeutic antiasthmatic efficacy due to the presence of potential bioactive compounds.

Methods:

Different databases were searched (ie, Embase, PubMed, CBM, AMED, and CINAHL). We have reviewed the published data of the last 20 years. We used MeSH terms “asthma” herbal treatment of asthma, allopathic treatment of asthma, and treatment strategies for asthma. The traditional medicine was compared with modern medicine and the same pharmacotherapies alone or with placebo. The methodology was evaluated by using the GRADE summary of Finding tables and Cochrane Risk of Bias Tool.

Results:

There have been some clear-cut indications toward the recognition of further molecular and cellular mechanisms of asthma. Most of them recommend a further target for treatment. The novel procedures, biologics, and pharmaceuticals are evaluated. Both allopathic and herbal treatments of asthma are effective. Due to none or lesser side effects, herbal medicines are safer than conventional medicine.

Conclusion:

The preliminary documentation of the plants discussed in the review show the presence of several secondary metabolites that are responsible for the management of asthma and its relevant complications. Further research studies are needed to identify the bioactive compounds from these plants that have potential efficacy to cure asthma, and clinically based studies are needed to search for a complete cure for this disease.

Inhibition of MAPK and STAT3-SOCS3 by Sakuranetin Attenuated Chronic Allergic Airway Inflammation in Mice

Asthma allergic disease is caused by airway chronic inflammation. Some intracellular signaling pathways, such as MAPK and STAT3-SOCS3, are involved in the control of airway inflammation in asthma. The flavonoid sakuranetin demonstrated an anti-inflammatory effect in different asthma models. Our aim was to clarify how sakuranetin treatment affects MAPK and STAT3-SOCS3 pathways in a murine experimental asthma model. Mice were submitted to an asthma ovalbumin-induction protocol and were treated with vehicle, sakuranetin, or dexamethasone. We assayed the inflammatory profile, mucus production, and serum antibody, STAT3-SOCS3, and MAPK levels in the lungs. Morphological alterations were also evaluated in the liver. LPS-stimulated RAW 264.7 cells were used to evaluate the effects of sakuranetin on nitric oxide (NO) and cytokine production. In vivo, sakuranetin treatment reduced serum IgE levels, lung inflammation (eosinophils, neutrophils, and Th2/Th17 cytokines), and respiratory epithelial mucus production in ovalbumin-sensitized animals. Considering possible mechanisms, sakuranetin inhibits the activation of ERK1/2, JNK, p38, and STAT3 in the lungs. No alterations were found in the liver for treated animals. Sakuranetin did not modify in vitro cell viability in RAW 264.7 and reduced NO release and gene expression of IL-1β and IL-6 induced by LPS in these cells. In conclusion, our data showed that the inhibitory effects of sakuranetin on eosinophilic lung inflammation can be due to the inhibition of Th2 and Th17 cytokines and the inhibition of MAPK and STAT3 pathways, reinforcing the idea that sakuranetin can be considered a relevant candidate for the treatment of inflammatory allergic airway disease.

The Enhanced Adhesion of Eosinophils Is Associated with Their Prolonged Viability and Pro-Proliferative Effect in Asthma

Before eosinophils migrate into the bronchial lumen, they promote airway structural changes after contact with pulmonary cells and extracellular matrix components. We aimed to investigate the impact of eosinophil adhesion to their viability and pro-proliferative effect on airway smooth muscle (ASM) cells and pulmonary fibroblasts during different asthma phenotypes. A total of 39 individuals were included: 14 steroid-free non-severe allergic asthma (AA) patients, 10 severe non-allergic eosinophilic asthma (SNEA) patients, and 15 healthy control subjects (HS). For AA patients and HS groups, a bronchial allergen challenge with Dermatophagoides pteronysinnus was performed. Individual combined cells cultures were prepared between isolated peripheral blood eosinophils and ASM cells or pulmonary fibroblasts. Eosinophil adhesion was measured by evaluating their peroxidase activity, cell viability was performed by annexin V and propidium iodide staining, and proliferation by Alamar blue assay. We found that increased adhesion of eosinophils was associated with prolonged viability (p < 0.05) and an enhanced pro-proliferative effect on ASM cells and pulmonary fibroblasts in asthma (p < 0.05). However, eosinophils from SNEA patients demonstrated higher viability and inhibition of pulmonary structural cell apoptosis, compared to the AA group (p < 0.05), while their adhesive and pro-proliferative properties were similar. Finally, in the AA group, in vivo allergen-activated eosinophils demonstrated a higher adhesion, viability, and pro-proliferative effect on pulmonary structural cells compared to non-activated eosinophils (p < 0.05).

Prevotella intermedia and periodontitis are associated with severe asthma

BACKGROUND

Periodontitis, an inflammatory disease of multibacterial etiology that affects the protective and supporting tissues surrounding teeth, can influence the course of respiratory diseases, such as asthma, due to epithelial alterations arising from inflammatory and immunological processes, bronchial remodeling, or by the aspiration of pathogenic colonizers found in periodontal pockets. This study evaluated the levels of periodontal pathogens Prevotella intermedia, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Aggregatibacter actinomycetemcomitans in the subgingival biofilm of individuals with and without severe asthma.

METHODS

A case-control study enrolling 457 individuals (220 with asthma and 237 without asthma) was conducted at the Program for Control of Asthma in Bahia (ProAR) Clinic located in Salvador, Bahia, Brazil. A structured questionnaire was used to obtain data on sociodemographic, health status, and lifestyle habits. A clinical periodontal assessment was performed, including bleeding on probing, probing depth, and clinical attachment level. Subgingival biofilm was collected at the deepest site of each sextant, and bacterial DNA was extracted. Quantitative real-time PCR analysis was performed to detect and relatively quantify periodontopathogens in the biofilm.

RESULTS

Statistically significant positive associations were found between periodontitis and severe asthma, (odds ratio [OR]_adjusted] : 4.00; 95% confidence interval [CI]: 2.26 to 7.10). High levels of P. intermedia were found in association with the presence of severe asthma (OR_adjusted : 2.64; 95% CI: 1.62 to 4.39; P < 0.01).

CONCLUSIONS

The present results suggest that periodontitis and P. intermedia are associated with severe asthma. However, the functional consequences of this dysbiosis upon asthma susceptibility and its phenotypes remain unclear.

Asthma, Sinonasal Disease, and the Risk of Active Tuberculosis

BACKGROUND

Although asthma is associated with impaired lung immunity, it is unclear whether asthma affects the risk of active tuberculosis (TB). Because the upper and lower airways are immunologically related, sinonasal disease may also modify susceptibility to TB disease.

OBJECTIVES

To evaluate whether asthma and sinonasal disease prospectively modulate the risk of active TB in the Singapore Chinese Health Study.

METHODS

In this population-based prospective cohort, we recruited 63,257 Chinese adults aged 45 to 74 years from 1993 to 1998 in Singapore, and conducted follow-up I interviews among 52,325 surviving participants from 1999 to 2004. Data on self-reported history of physician-diagnosed sinonasal disease were collected at baseline, and data on asthma and chronic bronchitis were collected at follow-up I interviews. Active TB cases were identified by linkage with the National TB Notification Registry through December 2014. Multivariable Cox proportional hazards regression models were used to estimate the risk of active TB.

RESULTS

During a mean follow-up of 17 years from recruitment, there were 1249 cases of active TB, and among them, 678 cases were diagnosed in the 12-year period from follow-up I interviews. We observed reduced risk of active TB in those with a history of asthma at follow-up I (hazard ratio [HR], 0.55; 95% CI, 0.32-0.93) or sinonasal disease at baseline (HR, 0.59; 95% CI, 0.36-0.95). Conversely, history of chronic bronchitis was not associated with risk of TB (HR, 0.95; 95% CI, 0.68-1.31).

CONCLUSIONS

Asthma or sinonasal disease may modulate immunological response to reduce the incidence of active TB in the adult population.

Sulfur dioxide exposure reduces the quantity of CD19+ cells and causes nasal epithelial injury in rats

Background

Reactive airway dysfunction syndrome (RADS), also called irritant-induced asthma, is a type of occupational asthma that can occur within a very short period of latency. The study sought to investigate the influence of sulfur dioxide (SO₂) exposure on CD19+ cells and nasal epithelial injury.

Methods

We investigated the effects of SO₂ on CD19 expression and morphological changes of nasal epithelia in rats. In the study, 20 rats were randomly divided into the SO₂ exposure group that were exposed to 600 ppm SO₂, 2 h/day for consecutive 7 days, and the control group that were exposed to filtered air).

Results

Inhalation of high concentration of SO₂significantly reduced CD19 expression at both the mRNA transcript and protein levels, and reduced the percentages of CD19⁺ cells and CD19⁺/CD23⁺ cells in the nasal septum. However, inhalation of high concentration of SO₂ did not affect immunoglobulin (Ig) G, IgA and IgE levels in the serum and nasal septum. More importantly, SO₂ exposure also caused mild structural changes of the nasal septum.

Conclusion

Our results reveal that inhalation of a high concentration of SO₂ reduces CD19 expression and causes structural change of the nasal septum in rats.

Cerium dioxide nanoparticles exacerbate house dust mite induced type II airway inflammation

Background

Nanomaterial inhalation represents a potential hazard for respiratory conditions such as asthma. Cerium dioxide nanoparticles (CeO₂NPs) have the ability to modify disease outcome but have not been investigated for their effect on models of asthma and inflammatory lung disease. The aim of this study was to examine the impact of CeO₂NPs in a house dust mite (HDM) induced murine model of asthma.

Results

Repeated intranasal instillation of CeO₂NPs in the presence of HDM caused the induction of a type II inflammatory response, characterised by increased bronchoalveolar lavage eosinophils, mast cells, total plasma IgE and goblet cell metaplasia. This was accompanied by increases in IL-4, CCL11 and MCPT1 gene expression together with increases in the mucin and inflammatory regulators CLCA1 and SLC26A4. CLCA1 and SLC26A4 were also induced by CeO₂NPs + HDM co-exposure in air liquid interface cultures of human primary bronchial epithelial cells. HDM induced airway hyperresponsiveness and airway remodelling in mice were not altered with CeO₂NPs co-exposure. Repeated HMD instillations followed by a single exposure to CeO₂NPs failed to produce changes in type II inflammatory endpoints but did result in alterations in the neutrophil marker CD177. Treatment of mice with CeO₂NPs in the absence of HDM did not have any significant effects. RNA-SEQ was used to explore early effects 24 h after single treatment exposures. Changes in SAA3 expression paralleled increased neutrophil BAL levels, while no changes in eosinophil or lymphocyte levels were observed. HDM resulted in a strong induction of type I interferon and IRF3 dependent gene expression, which was inhibited with CeO₂NPs co-exposure. Changes in the expression of genes including CCL20, CXCL10, NLRC5, IRF7 and CLEC10A suggest regulation of dendritic cells, macrophage functionality and IRF3 modulation as key early events in how CeO₂NPs may guide pulmonary responses to HDM towards type II inflammation.

Conclusions

CeO₂NPs were observed to modulate the murine pulmonary response to house dust mite allergen exposure towards a type II inflammatory environment. As this type of response is present within asthmatic endotypes this finding may have implications for how occupational or incidental exposure to CeO₂NPs should be considered for those susceptible to disease.

Electronic supplementary material

The online version of this article (10.1186/s12989-018-0261-5) contains supplementary material, which is available to authorized users.

A 4-Week Model of House Dust Mite (HDM) Induced Allergic Airways Inflammation with Airway Remodeling

Animal models of allergic airways inflammation are useful tools in studying the pathogenesis of asthma and potential therapeutic interventions. The different allergic airways inflammation models available to date employ varying doses, frequency, duration and types of allergen, which lead to the development of different features of asthma; showing varying degrees of airways inflammation and hyper-responsiveness (AHR) and airways remodeling. Models that also exhibit airway remodeling, a key feature of asthma, in addition to AHR and airway inflammation typically require 5–12 weeks to develop. In this report, we describe a 4-week mouse model of house dust mite (HDM)-induced allergic airways inflammation, and compare the phenotypic features of two different doses of HDM exposures (10 µg and 25 µg) for 5 days/week with a well-characterized 8-week chronic HDM model. We found that 4 weeks of intranasal HDM (25 µg in 35 µl saline; 5 days/week) resulted in AHR, airway inflammation and airway remodeling that were comparable to the 8-week model. We conclude that this new 4-week HDM model is another useful tool in studies of human asthma that offers advantages of shorter duration for development and decreased costs when compared to other models that require longer durations of exposure (5–12 weeks) to develop.

A prominent air pollutant, Indeno[1,2,3-cd]pyrene, enhances allergic lung inflammation via aryl hydrocarbon receptor

Chronic exposure to ambient polycyclic aromatic hydrocarbons (PAHs) is associated with asthma, but its regulatory mechanisms remain incompletely defined. We report herein that elevated levels of urinary 1-hydroxypyrene, a biomarker of PAH exposure, were found in asthmatic subjects (n = 39) as compared to those in healthy subjects (n = 43) living in an industrial city of Taiwan, where indeno[1,2,3-cd]pyrene (IP) was found to be a prominent PAH associated with ambient PM2.5. In a mouse model, intranasal exposure of mice with varying doses of IP significantly enhanced antigen-induced allergic inflammation, including increased airway eosinophilia, Th2 cytokines, including IL-4 and IL-5, as well as antigen-specific IgE level, which was absent in dendritic cell (DC)-specific aryl hydrocarbon receptor (AhR)-null mice. Mechanistically, IP treatment significantly altered DC's function, including increased level of pro-inflammatory IL-6 and decreased generation of anti-inflammatory IL-10. The IP's effect was lost in DCs from mice carrying an AhR-mutant allele. Taken together, these results suggest that chronic exposure to environmental PAHs may pose a significant risk for asthma, in which IP, a prominent ambient PAH in Taiwan, was shown to enhance the severity of allergic lung inflammation in mice through, at least in part, its ability in modulating DC's function in an AhR-dependent manner.

Large-scale profiling of signalling pathways reveals an asthma specific signature in bronchial smooth muscle cells

Background

Bronchial smooth muscle (BSM) cells from asthmatic patients maintain in vitro a distinct hyper-reactive (“primed”) phenotype, characterized by increased release of pro-inflammatory factors and mediators, as well as hyperplasia and/or hypertrophy. This “primed” phenotype helps to understand pathogenesis of asthma, as changes in BSM function are essential for manifestation of allergic and inflammatory responses and airway wall remodelling.

Objective

To identify signalling pathways in cultured primary BSMs of asthma patients and non-asthmatic subjects by genome wide profiling of differentially expressed mRNAs and activated intracellular signalling pathways (ISPs).

Methods

Transcriptome profiling by cap-analysis-of-gene-expression (CAGE), which permits selection of preferentially capped mRNAs most likely to be translated into proteins, was performed in human BSM cells from asthmatic (n=8) and non-asthmatic (n=6) subjects and OncoFinder tool were then exploited for identification of ISP deregulations.

Results

CAGE revealed >600 RNAs differentially expressed in asthma vs control cells (p≤0.005), with asthma samples showing a high degree of similarity among them. Comprehensive ISP activation analysis revealed that among 269 pathways analysed, 145 (p<0.05) or 103 (p<0.01) are differentially active in asthma, with profiles that clearly characterize BSM cells of asthmatic individuals. Notably, we identified 7 clusters of coherently acting pathways functionally related to the disease, with ISPs down-regulated in asthma mostly targeting cell death-promoting pathways and up-regulated ones affecting cell growth and proliferation, inflammatory response, control of smooth muscle contraction and hypoxia-related signalization.

Conclusions

These first-time results can now be exploited toward development of novel therapeutic strategies targeting ISP signatures linked to asthma pathophysiology.

The effect of exposure of SO2 in high concentrations on CD19+ cells in reactive airway dysfunction syndrome in rat

Reactive airway dysfunction syndrome (RADS) has a clinical manifestation similar to asthma, but some features are different between both the diseases. To probe the effect of CD19+ cells in RADS pathogenesis by inhalation of sulfur dioxide (SO2), rats were exposed to SO2 at 600 ppm for 2 h per day for 7 days and the CD19 expression in lung tissue was detected both at mRNA and protein levels by RT-PCR and western blot. The percentages of CD19+ and CD19+ CD23+ cells were measured by flow cytometry. IgG, IgA, and IgE in serum and bronchoalveolar lavage fluid (BALF) were detected by enzyme-linked immunosorbent assay (ELISA). Histological analysis was performed. The results showed that expression of CD19 in SO2 exposure group was lower than that in the control both at mRNA and protein levels ( P < 0.05). Flow cytometry analysis showed that the percentages of CD19+ and CD19+ CD23+ were significantly lower in the SO2 exposed group than that in the control ( P < 0.05). There was no difference between the control and SO2 exposed groups in both serum and BALF levels of IgG, IgA, and IgE. Pathological changes, such as chronic bronchitis, local alveolar hemorrhage, and lymphocytes infiltration were observed in SO2 exposed. RADS is a non-immunogenicity, chronic airway inflammatory disease caused by irritation of harmful factor and manifests as airway hyperresposiveness.

Mechanistic insight into the impact of nanomaterials on asthma and allergic airway disease

Asthma is a chronic respiratory disease known for its high susceptibility to environmental exposure. Inadvertent inhalation of engineered or incidental nanomaterials is a concern for human health, particularly for those with underlying disease susceptibility. In this review we provide a comprehensive analysis of those studies focussed on safety assessment of different nanomaterials and their unique characteristics on asthma and allergic airway disease. These include in vivo and in vitro approaches as well as human and population studies. The weight of evidence presented supports a modifying role for nanomaterial exposure on established asthma as well as the development of the condition. Due to the variability in modelling approaches, nanomaterial characterisation and endpoints used for assessment in these studies, there is insufficient information for how one may assign relative hazard potential to individual nanoscale properties. New developments including the adoption of standardised models and focussed in vitro and in silico approaches have the potential to more reliably identify properties of concern through comparative analysis across robust and select testing systems. Importantly, key to refinement and choice of the most appropriate testing systems is a more complete understanding of how these materials may influence disease at the cellular and molecular level. Detailed mechanistic insight also brings with it opportunities to build important population and exposure susceptibilities into models. Ultimately, such approaches have the potential to more clearly extrapolate relevant toxicological information, which can be used to improve nanomaterial safety assessment for human disease susceptibility.

Effect of airway remodeling and hyperresponsiveness on complexity of breathing pattern in rat

The complexity of respiratory dynamics is decreased, in association with disease severity, in patients with asthma. However, the pathophysiological basis of decreased complexity of breathing pattern in asthma is not clear. In the present study, we investigated the effect of airway remodeling and hyperresponsiveness induced by repeated bronchoconstriction (using methacholine) on breathing pattern in rats with or without allergen-induced sensitization. Entropy analysis of respiratory variability showed decreased irregularity (less complexity) of respiratory rhythm in this rat model of asthma. Airway remodeling and hyperresponsiveness induced by repeated bronchoconstriction also led to increased regularity of respiratory dynamics in sensitized rats. However, these airway alterations had no significant effect on the complexity of breathing pattern in non-sensitized rats. Our results indicate that mechanical respiratory alterations cannot per se attenuate the complexity of respiratory dynamics, unless there is an underlying inflammation. We suggest further studies on underlying mechanisms of breathing variability with focus on respiratory control alterations due to airway inflammation.

15-Deoxy-Delta-12,14-Prostaglandin J2 Inhibits Lung Inflammation and Remodeling in Distinct Murine Models of Asthma

15-deoxy-Δ-12,14-prostaglandin J₂ (15d-PGJ₂) has been described as an anti-inflammatory lipid mediator in several in vitro and in vivo studies, but its effect on allergic pulmonary inflammation remains elusive. The aim of this study was to investigate the therapeutic potential of 15d-PGJ₂ based on distinct murine models of allergic asthma triggered by either ovalbumin (OVA) or house dust mite extract (HDM). Characteristics of lung inflammation, airway hyper-reactivity (AHR), mucus exacerbation, and lung remodeling in sensitized A/J mice treated or not with 15d-PGJ₂ were assessed. 15d-PGJ₂ treatments were carried out systemically or topically given via subcutaneous injection or intranasal instillation, respectively. Analyses were carried out 24 h after the last allergen provocation. Irrespective of the route of administration, 15d-PGJ₂ significantly inhibited the peribronchial accumulation of eosinophils and neutrophils, subepithelial fibrosis and also mucus exacerbation caused by either OVA or HDM challenge. The protective effect of 15d-PGJ₂ occurred in parallel with inhibition of allergen-induced AHR and lung tissue production of pro-inflammatory cytokines, such as interleukin (IL)-5, IL-13, IL-17, and TNF-α. Finally, 15d-PGJ₂ was found effective in inhibiting NF-κB phosphorylation upon HDM challenge as measured by Western blotting. In conclusion, our findings suggest that 15d-PGJ₂ can reduce crucial features of asthma, including AHR, lung inflammation, and remodeling in distinct murine models of the disease. These effects are associated with a decrease in lung tissue generation of pro-inflammatory cytokines by a mechanism related to downregulation of NF-κB phosphorylation.

Diesel exhaust particulate associated chemicals attenuate expression of CXCL10 in human primary bronchial epithelial cells

Air pollution affects a large proportion of the population particularly in urban areas, with diesel particulates recognised as particular causes for concern in respiratory conditions such as asthma. In this study we examined the response of human primary airway epithelial cells to diesel particulate chemical extracts (DE) and characterised gene expression alterations using RNA-SEQ. Using the antagonist CH223191, DE induced CYP1A1 and attenuation of CXCL10 among other genes were observed to be aryl hydrocarbon receptor dependent. Basal and toll like receptor dependent protein levels for CXCL10 were markedly reduced. Investigation of similar regulation in plasmacytoid dendritic GEN2.2 cells did not show DE dependent regulation of CXCL10. Instillation of DE into mice to recapitulate airway epithelial exposure to chemical extracts in an in vivo setting failed to demonstrate a reduction in CXCL10. There was however an increase in the Th2 type epithelial cell derived inflammatory mediators TSLP and SERPINB2. We also observed an increased macrophages and a decrease in the proportion of lymphocytes in bronchoalveolar lavage fluid. CXCL10 can play a role in allergic airway disease through recruitment of Th1 type CD4+ T-cells, which can act to counterbalance Th2 type allergic responses. Modulation of such chemokines within the airway epithelium may represent a mechanism through which pollutant material can modify respiratory conditions such as allergic asthma.

Mitochondrial Dysfunction in Airway Disease

There is increasing appreciation that mitochondria serve cellular functions beyond oxygen sensing and energy production. Accordingly, it has become important to explore noncanonical roles of mitochondria in normal and pathophysiological processes that influence airway structure and function in the context of diseases such as asthma and COPD. Mitochondria can sense upstream processes such as inflammation, infection, tobacco smoke, and environmental insults important in these diseases and in turn can respond to such stimuli through altered mitochondrial protein expression, structure, and resultant dysfunction. Conversely, mitochondrial dysfunction has downstream influences on cytosolic and mitochondrial calcium regulation, airway contractility, gene and protein housekeeping, responses to oxidative stress, proliferation, apoptosis, fibrosis, and certainly metabolism, which are all key aspects of airway disease pathophysiology. Indeed, mitochondrial dysfunction is thought to play a role even in normal processes such as aging and senescence and in conditions such as obesity, which impact airway diseases. Thus, understanding how mitochondrial structure and function play central roles in airway disease may be critical for the development of novel therapeutic avenues targeting dysfunctional mitochondria. In this case, it is likely that mitochondria of airway epithelium, smooth muscle, and fibroblasts play differential roles, consistent with their contributions to disease biology, underlining the challenge of targeting a ubiquitous cellular element of existential importance. This translational review summarizes the current state of understanding of mitochondrial processes that play a role in airway disease pathophysiology and identifying areas of unmet research need and opportunities for novel therapeutic strategies.

Oral administration of Lactobacillus paracasei L9 attenuates PM2.5-induced enhancement of airway hyperresponsiveness and allergic airway response in murine model of asthma

This study investigated allergy immunotherapy potential of Lactobacillus paracasei L9 to prevent or mitigate the particulate matter 2.5 (PM2.5) enhanced pre-existing asthma in mice. Firstly, we used a mouse model of asthma (a 21-day ovalbumin (OVA) sensitization and challenge model) followed by PM2.5 exposure twice on the same day of the last challenge. PM2.5 was collected from the urban area of Beijing and underwent analysis for metals and polycyclic aromatic hydrocarbon contents. The results showed that PM2.5 exposure enhanced airway hyper-responsiveness (AHR) and lead to a mixed Th2/ IL-17 response in asthmatic mice. Secondly, the PM2.5 exposed asthmatic mice were orally administered with L9 (4×107, 4×109 CFU/mouse, day) from the day of first sensitization to the endpoint, for 20 days, to investigate the potential mitigative effect of L9 on asthma. The results showed that L9 ameliorated PM2.5 exposure enhanced AHR with an approximate 50% decrease in total airway resistance response to methacholine (48 mg/ml). L9 also prevented the exacerbated eosinophil and neutrophil infiltration in bronchoalveolar lavage fluid (BALF), and decreased the serum level of total IgE and OVA-specific IgG1 by 0.44-fold and 0.3-fold, respectively. Additionally, cytokine production showed that L9 significantly decreased T-helper cell type 2 (Th2)-related cytokines (IL-4, -5, -13) and elevated levels of Th1 related IFN-γ in BALF. L9 also reduced the level of IL-17A and increased the level of TGF-β. Taken together, these results indicate that L9 may exert the anti-allergic benefit, possibly through rebalancing Th1/Th2 immune response and modulating IL-17 pro-inflammatory immune response. Thus, L9 is a promising candidate for preventing PM exposure enhanced pre-existing asthma.

Oral administration of Lactobacillus paracasei L9 attenuates PM2.5-induced enhancement of airway hyperresponsiveness and allergic airway response in murine model of asthma

This study investigated allergy immunotherapy potential of Lactobacillus paracasei L9 to prevent or mitigate the particulate matter 2.5 (PM2.5) enhanced pre-existing asthma in mice. Firstly, we used a mouse model of asthma (a 21-day ovalbumin (OVA) sensitization and challenge model) followed by PM2.5 exposure twice on the same day of the last challenge. PM2.5 was collected from the urban area of Beijing and underwent analysis for metals and polycyclic aromatic hydrocarbon contents. The results showed that PM2.5 exposure enhanced airway hyper-responsiveness (AHR) and lead to a mixed Th2/ IL-17 response in asthmatic mice. Secondly, the PM2.5 exposed asthmatic mice were orally administered with L9 (4×107, 4×109 CFU/mouse, day) from the day of first sensitization to the endpoint, for 20 days, to investigate the potential mitigative effect of L9 on asthma. The results showed that L9 ameliorated PM2.5 exposure enhanced AHR with an approximate 50% decrease in total airway resistance response to methacholine (48 mg/ml). L9 also prevented the exacerbated eosinophil and neutrophil infiltration in bronchoalveolar lavage fluid (BALF), and decreased the serum level of total IgE and OVA-specific IgG1 by 0.44-fold and 0.3-fold, respectively. Additionally, cytokine production showed that L9 significantly decreased T-helper cell type 2 (Th2)-related cytokines (IL-4, -5, -13) and elevated levels of Th1 related IFN-γ in BALF. L9 also reduced the level of IL-17A and increased the level of TGF-β. Taken together, these results indicate that L9 may exert the anti-allergic benefit, possibly through rebalancing Th1/Th2 immune response and modulating IL-17 pro-inflammatory immune response. Thus, L9 is a promising candidate for preventing PM exposure enhanced pre-existing asthma.

Syk Regulates Neutrophilic Airway Hyper-Responsiveness in a Chronic Mouse Model of Allergic Airways Inflammation

Background

Asthma is a chronic inflammatory disease characterized by airways hyper-responsiveness (AHR), reversible airway obstruction, and airway inflammation and remodeling. We previously showed that Syk modulates methacholine-induced airways contractility in naïve mice and in mice with allergic airways inflammation. We hypothesize that Syk plays a role in the pathogenesis of AHR; this was evaluated in a chronic 8-week mouse model of house dust mite (HDM)-induced allergic airways inflammation.

Methods

We used the Syk^flox/flox//rosa26CreER^T2 conditional Syk knock-out mice to assess the role of Syk prior to HDM exposure, and treated HDM-sensitized mice with the Syk inhibitor, GSK143, to evaluate its role in established allergic airways inflammation. Respiratory mechanics and methacholine (MCh)-responsiveness were assessed using the flexiVent^® system. Lungs underwent bronchoalveolar lavage to isolate inflammatory cells or were frozen for determination of gene expression in tissues.

Results

MCh-induced AHR was observed following HDM sensitization in the Syk-intact (Syk^flox/flox) and vehicle-treated BALB/c mice. MCh responsiveness was reduced to control levels in HDM-sensitized Syk^del/del mice and in BALB/c and Syk^flox/flox mice treated with GSK143. Both Syk^del/del and GSK143-treated mice mounted appropriate immune responses to HDM, with HDM-specific IgE levels that were comparable to Syk^flox/flox and vehicle-treated BALB/c mice. HDM-induced increases in bronchoalveolar lavage cell counts were attenuated in both Syk^del/del and GSK143-treated mice, due primarily to decreased neutrophil recruitment. Gene expression analysis of lung tissues revealed that HDM-induced expression of IL-17 and CXCL-1 was significantly attenuated in both Syk^del/del and GSK143-treated mice.

Conclusion

Syk inhibitors may play a role in the management of neutrophilic asthma.

'The Microbiome and the Pathophysiology of Asthma'

Asthma is a chronic respiratory disease whose prevalence is increasing in the western world. Recently research has begun to focus on the role the microbiome plays in asthma pathogenesis in the hope of further understanding this respiratory disorder. Considered sterile until recently, the lungs have revealed themselves to contain a unique microbiota. A shift towards molecular methods for the quantification and sequencing of microbial DNA has revealed that the airways harbour a unique microbiota with apparent, reproducible differences present between healthy and diseased lungs. There is a hope that in classifying the microbial load of the asthmatic airway an insight may be afforded as to the possible role pulmonary microbes may have in propagating an asthmatic airway response. This could potentially pave the way for new therapeutic strategies for the treatment of chronic lung conditions such as asthma.

The effects of a CXCR1/CXCR2 antagonist on neutrophil migration in mild atopic asthmatic subjects

BACKGROUND

Neutrophils are effector cells recruited to airways in patients with asthma. Migration of neutrophils occurs predominantly through activation of the CXCR1 and CXCR2 receptors by CXC chemokines, including IL-8 and Gro-α. The dual CXCR1/CXCR2 antagonist SCH 527123 has been developed to target neutrophil migration to alleviate airway neutrophilia. This study investigated the effects of SCH 527123 on neutrophil levels within the bone marrow, peripheral blood and airways, and on isolated bone marrow and peripheral blood neutrophil migration from mild allergic asthmatics.

METHODS

Thirteen subjects with mild allergic asthma completed a double blind, placebo-controlled, multi-center crossover study and were randomized to daily dosing of 30 mg SCH 527123 and placebo for 8 days. Subjects provided bone marrow, peripheral blood and sputum samples pre-dosing and on the last day of dosing. Neutrophil numbers were quantified in all samples and chemotaxis assays were performed on neutrophils purified from bone marrow and peripheral blood.

RESULTS

Neutrophil numbers fell significantly in the peripheral blood and sputum following treatment with SCH 527123 compared to placebo treatment. No change in neutrophil numbers was observed in bone marrow. SCH 527123 reduced IL-8-induced migration of purified peripheral blood neutrophils (p < 0.05), but had limited effects on migration of neutrophils purified from bone marrow.

CONCLUSIONS

The results from this study demonstrate that oral administration of the dual CXCR1/CXCR2 antagonist SCH 527123 reduces neutrophil levels in the circulation and airways through inhibition of migration. There were no toxic effects of SCH 527123 on granulocytic progenitor cells in the bone marrow.

A 12-week open-label, randomized, controlled trial and 24-week extension to assess the efficacy and safety of fluticasone propionate/formoterol in children with asthma

OBJECTIVES

The present study was conducted to assess the efficacy, safety and tolerability of fluticasone propionate/formoterol fumarate combination therapy (FP/FORM; Flutiform®) compared with fluticasone propionate/salmeterol xinafoate (FP/SAL; Seretide® Evohaler®) in children with asthma.

METHODS

This was an open-label, randomized, controlled, phase III trial and extension. Patients aged 4-12 years with reversible asthma [% predicted forced expiratory volume in 1 second (FEV1) 60-100%; documented reversibility of ⩾15% in FEV1] were randomized to receive FP/FORM (100/10 µg b.i.d.) or FP/SAL (100/50 µg b.i.d.) for 12 weeks. Eligible patients completing the 12-week core phase entered a 24-week extension phase with FP/FORM (100/10 µg b.i.d.). The primary efficacy endpoint was the change in predose FEV1 from day 0 to day 84. Secondary efficacy endpoints included change in predose to 2-hours postdose FEV1 from day 0 to day 84, peak expiratory flow rate (PEFR), patient-reported outcomes, rescue-medication use and asthma exacerbations.

RESULTS

In total, 211 patients were randomized and 210 completed the core phase; of these patients, 208 entered and 205 completed the extension phase of the study. Predose FEV1 increased from day 0 to day 84 [FP/FORM, 182 ml; 95% confidence interval (CI), 127, 236; FP/SAL, 212 ml, 95% CI, 160, 265] and FP/FORM was noninferior to FP/SAL: least squares (LS) mean treatment difference: -0.031 (95% CI, -0.093, 0.031; p = 0.026). Secondary efficacy analyses indicated similar efficacy with both therapies. There were no notable differences observed in the safety and tolerability profile between treatments. No safety concerns were identified with long-term FP/FORM therapy, and there was no evidence of an effect of FP/FORM on plasma cortisol.

CONCLUSIONS

FP/FORM improved lung function and measures of asthma control with comparable efficacy to FP/SAL, and demonstrated a favourable safety and tolerability profile in children aged 4-12 years.