Associations of prenatal ambient air pollution exposures with asthma in middle childhood

We examined associations between prenatal fine particulate matter (PM2.5), nitrogen dioxide (NO2), and ozone (O3) exposures and child respiratory outcomes through age 8-9 years in 1279 ECHO-PATHWAYS Consortium mother-child dyads. We averaged spatiotemporally modeled air pollutant exposures during four fetal lung development phases: pseudoglandular (5-16 weeks), canalicular (16-24 weeks), saccular (24-36 weeks), and alveolar (36+ weeks). We estimated adjusted relative risks (RR) for current asthma at age 8-9 and asthma with recent exacerbation or atopic disease, and odds ratios (OR) for wheezing trajectories using modified Poisson and multinomial logistic regression, respectively. Effect modification by child sex, maternal asthma, and prenatal environmental tobacco smoke was explored. Across all outcomes, 95% confidence intervals (CI) included the null for all estimates of associations between prenatal air pollution exposures and respiratory outcomes. Pseudoglandular PM2.5 exposure modestly increased risk of current asthma (RRadj = 1.15, 95% CI: 0.88-1.51); canalicular PM2.5 exposure modestly increased risk of asthma with recent exacerbation (RRadj = 1.26, 95% CI: 0.86-1.86) and persistent wheezing (ORadj = 1.28, 95% CI: 0.86-1.89). Similar findings were observed for O3, but not NO2, and associations were strengthened among mothers without asthma. While not statistically distinguishable from the null, trends in effect estimates suggest some adverse associations of early pregnancy air pollution exposures with child respiratory conditions, warranting confirmation in larger samples.

Dexamethasone protects against asthma via regulating Hif-1α-glycolysis-lactate axis and protein lactylation

PURPOSE

Asthma can not be eradicated till now and its control primarily relies on the application of corticosteroids. Recently, glycolytic reprogramming has been reportedly contributed to asthma, this study aimed to reveal whether the effect of corticosteroids on asthma control is related to their regulation of glycolysis and glycolysis-dependent protein lactylation.

METHODS

Ovalbumin (OVA) aeroallergen was used to challenge mice and stimulate human macrophage cell line THP-1 following dexamethasone (DEX) treatment. Airway hyperresponsiveness, airway inflammation, the expressions of key glycolytic enzymes and pyroptosis markers, the level of lactic acid, real-time glycolysis and oxidative phosphorylation (OXPHOS), and protein lactylation were analyzed.

RESULTS

DEX significantly attenuated OVA-induced eosinophilic airway inflammation, including airway hyperresponsiveness, leukocyte infiltration, goblet cell hyperplasia, Th2 cytokines production and pyroptosis markers expression. Meanwhile, OVA-induced Hif-1α-glycolysis axis was substantially downregulated by DEX, which resulted in low level of lactic acid. Besides, key glycolytic enzymes in the lungs of asthmatic mice were notably co-localized with F4/80-positive macrophages, indicating metabolic shift to glycolysis in lung macrophages during asthma. This was confirmed in OVA-stimulated THP-1 cells that DEX treatment resulted in reductions in pyroptosis, glycolysis and lactic acid level. Finally, protein lactylation was found significantly increased in the lungs of asthmatic mice and OVA-stimulated THP-1 cells, which were both inhibited by DEX.

CONCLUSION

Our present study revealed that the effect of DEX on asthma control was associated with its suppressing of Hif-1α-glycolysis-lactateaxis and subsequent protein lactylation, which may open new avenues for the therapy of eosinophilic asthma.

Machine learning-driven identification of air toxic combinations associated with asthma symptoms among elementary school children in Spokane, Washington, USA

Air toxics are atmospheric pollutants with hazardous effects on health and the environment. Although methodological constraints have limited the number of air toxics assessed for associations with health and disease, advances in machine learning (ML) enable the assessment of a much larger set of environmental exposures. We used ML methods to conduct a retrospective study to identify combinations of 109 air toxics associated with asthma symptoms among 269 elementary school students in Spokane, Washington. Data on the frequency of asthma symptoms for these children were obtained from Spokane Public Schools. Their exposure to air toxics was estimated by using the Environmental Protection Agency's Air Toxics Screening Assessment and National Air Toxics Assessment. We defined three exposure periods: the most recent year (2019), the last three years (2017-2019), and the last five years (2014-2019). We analyzed the data using the ML-based Data-driven ExposurE Profile (DEEP) extraction method. DEEP identified 25 air toxic combinations associated with asthma symptoms in at least one exposure period. Three combinations (1,1,1-trichloroethane, 2-nitropropane, and 2,4,6-trichlorophenol) were significantly associated with asthma symptoms in all three exposure periods. Four air toxics (1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, BIS (2-ethylhexyl) phthalate (DEHP), and 2,4-dinitrophenol) were associated only in combination with other toxics, and would not have been identified by traditional statistical methods. The application of DEEP also identified a vulnerable subpopulation of children who were exposed to 13 of the 25 significant combinations in at least one exposure period. On average, these children experienced the largest number of asthma symptoms in our sample. By providing evidence on air toxic combinations associated with childhood asthma, our findings may contribute to the regulation of these toxics to improve children's respiratory health.

Endothelin-1-mediated Brainstem Glial Activation Produces Asthmatic Airway Vagal Hypertonia Via Enhanced ATP-P2X4 Receptor Signaling in Sprague-Dawley Rats

The occurrence of major asthma symptoms is largely attributed to airway vagal hypertonia, of which the central mechanisms remain unclear. This study tests the hypotheses that endothelin-1-mediated brainstem glial activation produces asthmatic airway vagal hypertonia via enhanced action of adenosine 5'-triphosphate on neuronal purinergic P2X4 receptors. A rat model of asthma was prepared using ovalbumin. Airway vagal tone was evaluated by the recurrent laryngeal discharge and plethysmographic measurement of pulmonary function. The changes in the brainstem were examined using ELISA, Western blot, luciferin-luciferase, quantitative reverse transcription-polymerase chain reaction, enzyme activity assay and immunofluorescent staining, respectively. The results showed that in the medulla of rats, endothelin receptor type B and P2X4 receptors were primarily expressed in astrocytes and neurons, respectively, and both of which, along with endothelin-1 content, were significantly increased after ovalbumin sensitization. Ovalbumin sensitization significantly increased recurrent laryngeal discharge, which was blocked by acute intracisternal injection of P2X4 receptor antagonist 5-BDBD, knockdown of brainstem P2X4 receptors, and chronic intraperitoneal injection of endothelin receptor type B antagonist BQ788, respectively. Ovalbumin sensitization activated microglia and astrocytes and significantly decreased ecto-5'-nucleotidase activity in the medulla, and all of which, together with the increase of medullary P2X4 receptor expression and decrease of pulmonary function, were reversed by chronic BQ788 treatment. These results demonstrated that in rats, allergic airway challenge activates both microglia and astrocytes in the medulla via enhanced endothelin-1/endothelin receptor type B signaling, which subsequently causes airway vagal hypertonia via augmented adenosine 5'-triphosphate/P2X4 receptor signaling in central neurons of airway vagal reflex.

Stigmasterol alleviates airway inflammation in OVA-induced asthmatic mice via inhibiting the TGF-β1/Smad2 and IL-17A signaling pathways

Stigmasterol is a common dietary phytosterol with high nutritional value and physiological activity. In this study, we evaluated the effects of stigmasterol on inflammatory cytokines and the TGF-β1/Smad2 and IL-17A signaling pathway in an ovalbumin (OVA)-induced asthma mouse model. Stigmasterol treatment improved airway remodeling. In addition, it significantly attenuated the symptoms of asthma attacks, reduced the number of macrophages, lymphocytes, neutrophils, and eosinophils in BALF and inflammatory cytokines, including IL-1β, IL-5, IL-6, and IL-13. It further decreased the level of IL-17A in BALF, serum and spleen. Spleen single-cell suspension analysis via flow cytometry showed that IL-17A level was consistent with the results obtained in BALF, serum and spleen. Stigmasterol decreased the protein expression levels of TGF-β, p-Smad2 and IL-17A in the spleen, by increasing the protein expression level of IL-10. After 24 h of co-culture of TGF-β, IL-6 and stigmasterol, the level of IL-17 in CD4+ T cell supernatant was lower relative to levels in the group without stigmasterol. Meanwhile, stigmasterol treatment attenuated the expression level of TGF- β, p-Smad2 and IL-17A proteins in CD4+ T cells and enhanced the expression levels of IL-10 protein. These data suggested that stigmasterol inhibited the TGF-β1/Smad2 and IL-17A signaling pathway to achieve anti-asthmatic effects in the OVA-induced asthma mouse model. Collectively, the results of this study are that stigmasterol has achieved preliminary efficacy in the non-clinical laboratory, further studies are needed to consider the clinical application of stigmasterol.

Wogonoside Ameliorates Airway Inflammation and Mucus Hypersecretion via NF-κB/STAT6 Signaling in Ovalbumin-Induced Murine Acute Asthma

Asthma is recognized as a chronic respiratory illness characterized by airway inflammation and airway hyperresponsiveness. Wogonoside, a flavonoid glycoside, is reported to significantly alleviate the inflammation response and oxidative stress. Herein, this study aimed to investigate the therapeutic effect and underlying mechanism of wogonoside on airway inflammation and mucus hypersecretion in a murine asthma model and in human bronchial epithelial cells (16HBE). BALB/c mice were sensitized and challenged with ovalbumin (OVA). Pulmonary function and the number of cells in the bronchoalveolar lavage fluid (BALF) were examined. Pathological changes in lung tissue in each group were evaluated via hematoxylin and eosin and periodic acid-Schiff staining, and changes in levels of cytokines in BALF and of immunoglobulin E in serum were determined via an enzyme-linked immunosorbent assay. The expression of relevant genes in lung tissue was analyzed via real-time PCR. Western blotting and immunofluorescence were employed to detect the expression of relevant proteins in lung tissue and 16HBE cells. Treatment with 10 and 20 mg/kg wogonoside significantly attenuated the OVA-induced increase of inflammatory cell infiltration, mucus secretion, and goblet cell percentage and improved pulmonary function. Wogonoside treatment reduced the level of T-helper 2 cytokines including interleukin (IL)-4, IL-5, and IL-13 in BALF and of IgE in serum and decreased the mRNA levels of cytokines (IL-4, IL-5, IL-6, IL-13, and IL-1β and tumor necrosis factor-α), chemokines (CCL-2, CCL-11, and CCL-24), and mucoproteins (MUC5AC, MUC5B, and GOB5) in lung tissues. The expression of MUC5AC and the phosphorylation of STAT6 and NF-κB p65 in lung tissues and 16HBE cells were significantly downregulated after wogonoside treatment. Thus, wogonoside treatment may effectively decrease airway inflammation, airway remodeling, and mucus hypersecretion via blocking NF-κB/STAT6 activation.

E-cigarettes exacerbate allergic inflammation via cytokine induction and MUC5AC/5B expression in a murine asthma model

The effects of electronic cigarettes (e-cigarettes) vapor on inflammation and mucin secretion on asthmatics remain insufficiently explored. This study investigated the effects of e-cigarette vapor on allergic inflammation, cytokine production, and MUC5AC/5B expression in murine asthma model. Airway hyperresponsiveness was significantly higher in the e-cigarette-exposed ovalbumin (OVA) sensitization group than in the control, e-cigarette exposure, and OVA sensitization groups. The e-cigarette-exposed OVA sensitization group showed significantly greater infiltration of inflammatory cells and Th2-mediated inflammatory cytokines (interleukin-4 and -5) compared to the control, e-cigarette exposure, and OVA sensitization groups. MUC5AC mucin levels were significantly elevated in the e-cigarette exposure, OVA sensitization, and e-cigarette-exposed OVA sensitization groups, whereas MUC5B mucin levels were significantly elevated in the OVA sensitization and e-cigarette-exposed OVA sensitization groups. The results may suggest that the exposure to e-cigarette vapor in an asthmatics promoted allergic inflammation and increased mucin secretion, ultimately leading to the exacerbation of asthma.

Protopine ameliorates OVA-induced asthma through modulatingTLR4/MyD88/NF-κB pathway and NLRP3 inflammasome-mediated pyroptosis

BACKGROUND

Chronic airway inflammation and hyperresponsiveness are characteristics of asthma. The isoquinoline alkaloid protopine (PRO) has been shown to exert anti-inflammatory effects, but its mechanism of action in asthma is not known.

PURPOSE

Investigate the protective properties of PRO upon asthma and elucidate its mechanism.

STUDY DESIGN AND METHODS

The effects of PRO in asthma treatment were assessed by histology, biochemical analysis, and real-time reverse transcription-quantitative polymerase chain reaction. Then, we integrated molecular docking, western blotting, cellular experiments, immunohistochemistry, immunofluorescence analysis, flow cytometry, and metabolomics analysis to reveal its mechanism.

RESULTS

In vivo, PRO therapy reduced the number of inflammatory cells (eosinophils, leukocytes, monocytes) in bronchoalveolar lavage fluid (BALF), ameliorated pathologic alterations in lung tissues, and inhibited secretion of IgG and histamine. Molecular docking showed that PRO could dock with the proteins of TLR4, MyD88, TRAF6, TAK1, IKKα, and TNF-α. Western blotting displayed that PRO inhibited the TLR4/NF-κB signaling pathway. PRO regulated expression of the pyroptosis-related proteins NLR family pyrin domain containing 3 (NLRP3) inflammasome, gasdermin D, caspase-1, and drove caspase-1 inactivation to affect inflammatory responses by inhibiting the NLRP3 inflammasome. In vitro, 24 h after treatment with PRO, cell activity, as well as levels of reactive oxygen species (ROS) and interleukin (IL)-1β and IL-18, decreased significantly. Immunofluorescence staining showed that PRO decreased expression of TLR4 and MyD88 in vitro. PRO decreased nuclear translocation of NF-κB p65. Twenty-one potential biomarkers in serum were identified using metabolomics analysis, and they predominantly controlled the metabolism of phenylalanine, tryptophan, glucose, and sphingolipids.

CONCLUSION

PRO reduced OVA-induced asthma. The underlying mechanism was associated with the TLR4/MyD88/NF-κB pathway and NLRP3 inflammasome-mediated pyroptosis.

The Use of Albuterol/Budesonide as Reliever Therapy to Reduce Asthma Exacerbations

Prevention of asthma exacerbations and reduction of systemic corticosteroid burden remain unmet needs in asthma. US asthma guidelines recommend concomitant short-acting β2-agonist (SABA) and inhaled corticosteroid (ICS) as an alternative reliever at step 2. The Food and Drug Administration approved a pressurized metered-dose inhaler containing albuterol and budesonide for as-needed treatment or prevention of bronchoconstriction and for reducing exacerbation risk in patients with asthma aged ≥18 years. This combination is approved for use as a reliever with or without maintenance therapy, but it is not indicated for maintenance therapy (or for single maintenance and reliever therapy). Intervening with as-needed SABA-ICS during the window of opportunity to reduce inflammation during loss of asthma control can reduce exacerbation risk, by exerting both genomic and nongenomic anti-inflammatory effects. We propose that the use of albuterol-budesonide rather than albuterol as a reliever to manage episodic symptoms driven by acute bronchoconstriction and airway inflammation can improve outcomes. This combination approach, shown to decrease asthma exacerbations and oral corticosteroid burden in patients with moderate-to-severe asthma, represents a paradigm shift for asthma treatment in the United States. Further safety and efficacy studies should provide evidence that this type of reliever should be standard of care.

Impact of dupilumab across seasons in patients with type 2, uncontrolled, moderate-to-severe asthma

BACKGROUND

Seasonal variability could influence asthma exacerbations. Dupilumab, a fully human monoclonal antibody, blocks the shared receptor component for interleukin (IL)-4/IL-13, key and central drivers of type 2 inflammation. In the 52-week QUEST study (NCT02414854), add-on dupilumab every 2 weeks vs placebo significantly reduced exacerbations and improved prebronchodilator forced expiratory volume in 1 second in patients with uncontrolled, moderate-to-severe asthma. TRAVERSE (NCT02134028), the open-label QUEST extension study, enrolled patients with moderate-to-severe asthma to investigate long-term safety and efficacy of dupilumab, including patients who previously received placebo that initiated dupilumab therapy.

OBJECTIVE

To investigate long-term dupilumab efficacy in reducing exacerbations across yearly seasons in patients with type 2 inflammatory asthma with and without clinical evidence of allergic asthma.

METHODS

Unadjusted annualized exacerbation rate and proportions of patients experiencing severe asthma exacerbations are reported by month and season and for both hemispheres.

RESULTS

The proportion of patients with type 2 asthma experiencing 1 or more severe asthma exacerbations during QUEST was 20.8% vs 10.0% in spring, 18.2% vs 7.3% in summer, 22.2% vs 12.6% in autumn, and 26.4% vs 12.0% in winter, for placebo- vs dupilumab-treated patients, respectively; P was less than .001 for placebo vs dupilumab in all seasons. Reductions in the proportion of patients experiencing severe exacerbations across seasons in subgroups with and without evidence of allergic asthma were similar to the overall type 2 population. Reductions in severe exacerbations observed during QUEST were sustained during TRAVERSE, up to 96 weeks across both hemispheres.

CONCLUSION

Dupilumab reduced asthma exacerbations, with no difference in the reduction between seasons, in patients with type 2 inflammation, with and without evidence of allergic asthma.

TRIAL REGISTRATION

ClinicalTrials.gov Identifiers: NCT02414854, NCT02134028.

Long-Term Safety of Dupilumab in Patients With Moderate-to-Severe Asthma: TRAVERSE Continuation Study

BACKGROUND

Previous clinical trials have demonstrated dupilumab efficacy and safety in adults and adolescents with moderate to severe asthma for up to 3 years.

OBJECTIVE

The TRAVERSE continuation study (NCT03620747), a single-arm, open-label study, assessed safety and tolerability of dupilumab 300 mg every 2 weeks up to an additional 144 weeks (∼3 years) in patients with moderate to severe asthma who previously completed TRAVERSE (NCT02134028).

METHODS

Primary end points were incidence and event rates per 100 patient-years of treatment-emergent adverse events (TEAEs). Secondary end points included adverse events (AEs) of special interest, serious AEs, and AEs leading to study discontinuation.

RESULTS

A total of 393 patients participated in the TRAVERSE continuation study (cumulative dupilumab exposure, 431.7 patient-years; median treatment duration, 309 days). A total of 29 patients (7.4%) received more than 958 days of treatment. A total of 214 (54.5%) patients reported at least 1 TEAE (event rate: 171.4); 37 (9.4%) experienced at least 1 treatment-related TEAE, none of which were considered severe; 2 patients reported 6 TEAEs of moderate intensity. A total of 22 (5.6%) patients reported serious AEs (event rate: 6.9). AEs of special interest were reported in 24 patients (6.1%; event rate: 6.0). Five (1.3%) deaths occurred (event rate: 1.2) following serious AEs of coronavirus disease 2019 (COVID-19)-related pneumonia (3 patients), pancreatitis (1 patient), and pulmonary embolism (1 patient). None of the TEAEs leading to death were considered treatment-related.

CONCLUSIONS

Dupilumab treatment was well tolerated for up to an additional 3 years. Safety findings were consistent with the known safety profile of dupilumab. These findings further support the long-term use of dupilumab in patients with moderate to severe asthma.

Dictamnus dasycarpus Turcz. attenuates airway inflammation and mucus hypersecretion by modulating the STAT6-STAT3/FOXA2 pathway

BACKGROUND

Effects of Dictamnus dasycarpus Turcz. on allergic asthma and their underlying mechanisms remain unclarified. Thus, we investigated the effects of D. dasycarpus Turcz. water extract (DDW) on mucus hypersecretion in mice with ovalbumin (OVA)-induced asthma and human bronchial epithelial cells.

METHODS

BALB/c mice were used to establish an OVA-induced allergic asthma model. Mice were grouped into the OVA sensitization/challenge, 100 and 300 mg/kg DDW treatment, and dexamethasone groups. In mice, cell counts in bronchoalveolar lavage fluid (BALF), serum and BALF analyses, and histopathological lung tissue analyses were performed. Furthermore, we confirmed the basic mechanism in interleukin (IL)-4/IL-13-treated human bronchial epithelial cells through western blotting.

RESULTS

In OVA-induced asthma mice, DDW treatment reduced inflammatory cell number and airway hyperresponsiveness and ameliorated histological changes (immune cell infiltration, mucus secretion, and collagen deposition) in lung tissues and serum total immunoglobulin E levels. DDW treatment lowered BALF IL-4, IL-5, and IL-13 levels; reduced levels of inflammatory mediators, such as thymus- and activation-regulated chemokine, macrophage-derived chemokine, and interferon gamma-induced protein; decreased mucin 5AC (MUC5AC) production; decreased signal transducer and activator of transcription (STAT) 6 and STAT3 expression; and restored forkhead box protein A2 (FOXA2) expression. In IL-4/IL-13-treated human bronchial epithelial cells, DDW treatment inhibited MUC5AC production, suppressed STAT6 and STAT3 expression (related to mucus hypersecretion), and increased FOXA2 expression.

CONCLUSIONS

DDW treatment modulates MUC5AC expression and mucus hypersecretion by downregulating STAT6 and STAT3 expression and upregulating FOXA2 expression. These findings provide a novel approach to manage mucus hypersecretion in asthma using DDW.

ITGAM-macrophage modulation as a potential strategy for treating neutrophilic Asthma: insights from bioinformatics analysis and in vivo experiments

Identification of molecular biomarkers associated with neutrophilic asthma (NA) phenotype may inform the discovery of novel pathobiological mechanisms and the development of diagnostic markers. Three mRNA transcriptome datasets extracted from induced sputum of asthma patients with various inflammatory types were used to screen for macrophage-related molecular mechanisms and targets in NA. Furthermore, the predicted targets were also validated on an independent dataset (N = 3) and animal model (N = 5). A significant increase in total cells, neutrophils and macrophages was observed in bronchoalveolar lavage (BAL) fluid of NA mice induced by ovalbumin/freund's adjuvant, complete (OVA/CFA). And we also found elevated levels of neutrophil and macrophage infiltration in NA subtype in external datasets. NA mice had increased secretion of IgE, IL-1β, TNF-α and IL-6 in serum and BAL fluid. MPO, an enzyme present in neutrophils, was also highly expressed in NA mice. Then, weighted gene co-expression network analysis (WGCNA) identified 684 targets with the strongest correlation with NA, and we obtained 609 macrophage-related specific differentially expressed genes (DEGs) in NA by integrating macrophage-related genes. The top 10 genes with high degree values were obtained and their mRNA levels and diagnostic performance were then determined by RT-qPCR and receiver operator characteristic (ROC) analysis. Statistically significant correlations were found between macrophages and all key targets, with the strongest correlation between ITGAM and macrophages in NA. Double-Immunofluorescence staining further confirmed the co-localization of ITGAM and F4/80 in NA. ITGAM was identified as a critical target to distinguish NA from healthy/non-NA individuals, which may provide a novel avenue to further uncover the mechanisms and therapy of NA.

Inhibition of xanthine oxidase by allopurinol suppresses HMGB1 secretion and ameliorates experimental asthma

BACKGROUND

Extracellular high mobility group box 1 (HMGB1) is a key mediator in driving allergic airway inflammation and contributes to asthma. Yet, mechanism of HMGB1 secretion in asthma is poorly defined. Pulmonary metabolic dysfunction is recently recognized as a driver of respiratory pathology. However, the altered metabolic signatures and the roles of metabolic to allergic airway inflammation remain unclear.

METHODS

Male C57BL/6 J mice were sensitized and challenged with toluene diisocyanate (TDI) to generate a chemically induced asthma model. Pulmonary untargeted metabolomics was employed. According to results, mice were orally administered allopurinol, a xanthine oxidase (XO) inhibitor. Human bronchial epithelial cells (16HBE) were stimulated by TDI-human serum albumin (HSA).

RESULTS

We identified the purine metabolism was the most enriched pathway in TDI-exposed lungs, corresponding to the increase of xanthine and uric acid, products of purine degradation mediated by XO. Inhibition of XO by allopurinol ameliorates TDI-induced oxidative stress and DNA damage, mixed granulocytic airway inflammation and Th1, Th2 and Th17 immunology as well as HMGB1 acetylation and secretion. Mechanistically, HMGB1 acetylation was caused by decreased activation of the NAD+-sirtuin 1 (SIRT1) axis triggered by hyperactivation of the DNA damage sensor poly (ADP-ribose)-polymerase 1 (PARP-1). This was rescued by allopurinol, PARP-1 inhibitor or supplementation with NAD+ precursor in a SIRT1-dependent manner. Meanwhile, allopurinol attenuated Nrf2 defect due to SIRT1 inactivation to help ROS scavenge.

CONCLUSIONS

We demonstrated a novel regulation of HMGB1 acetylation and secretion by purine metabolism that is critical for asthma onset. Allopurinol may have therapeutic potential in patients with asthma.

LINC00158 modulates the function of BEAS-2B cells via targeting BCL11B and ameliorates OVA-LPS-induced severe asthma in mice models

Persistent type (T) 2 airway inflammation plays an important role in the development of severe asthma. However, the molecular mechanisms leading to T2 severe asthma have yet to be fully clarified. Human normal lung epithelial cells (BEAS-2B cells) were transfected with LINC00158/BCL11B plasmid/small interfering RNA (siRNA). Levels of epithelial-mesenchymal transition (EMT)-related markers were measured using real-time qPCR (RT-qPCR) and western blot. A dual luciferase reporter assay was used to validate the targeting relationship between LINC00158 and BCL11B. The effects of LINC00158-lentivirus vector-mediated overexpression and dexamethasone on ovalbumin (OVA)/lipopolysaccharide (LPS)-induced severe asthma were investigated in mice in vivo. Our study showed that overexpression of LINC00158/BCL11B inhibited the levels of EMT-related proteins, apoptosis, and promoted the proliferation of BEAS-2B cells. BCL11B was a direct target of LINC00158. And LINC00158 targeted BCL11B to regulate EMT, apoptosis, and cell proliferation of BEAS-2B cells. Compared with severe asthma mice, LINC00158 overexpression alleviated OVA/LPS-induced airway hyperresponsiveness and airway inflammation, including reductions in T helper 2 cells factors in lung tissue and BALF, serum total- and OVA-specific IgE, inflammatory cell infiltration, and goblet cells hyperplasia. In addition, LINC00158 overexpression alleviated airway remodeling, including reduced plasma TGF-β1 and collagen fiber deposition, as well as suppression of EMT. Additionally, overexpression of LINC00158 enhanced the therapeutic effect of dexamethasone in severe asthmatic mice models. LINC00158 regulates BEAS-2B cell biological function by targeting BCL11B. LINC00158 ameliorates T2 severe asthma in vivo and provides new insights into the clinical treatment of severe asthma.

Multi-omics analysis of lung tissue metabolome and proteome reveals the therapeutic effect of Shegan Mahuang Decoction against asthma in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Shegan Mahuang Decoction (SMD) is a classic traditional Chinese medicine (TCM) formula for asthma treatment, but the anti-asthma mechanism of SMD is still not fully studied.

AIMS OF THE STUDY

In this study, we established an ovalbumin (OVA)-induced asthma rat model and treated it with SMD to observe its anti-asthma effect and explore the related mechanism.

MATERIALS AND METHODS

We evaluated the anti-inflammatory effect of SMD via testing the levels of immunoglobulin E (IgE), C-reactive protein (CRP), interleukin-4 (IL-4), interleukin-6 (IL-6) in serum and performing the hematoxylin-eosin (H&E) staining of lung tissue slices. We analyzed the variations of metabolites and proteins in the lung tissue of different groups using liquid chromatography-mass spectrometry (LC-MS)-based untargeted metabolomics and TMT-based proteomics approaches. The metabolic biomarkers and differentially expressed proteins (DEPs) were picked, and the related signal transduction pathways were also investigated. In addition, the key proteins on the signaling pathway were validated through western blotting (WB) experiment to reveal the anti-asthma mechanism of SMD.

RESULTS

The results showed that the SMD could significantly reduce the serum levels of IgE, CRP, IL-4, and IL-6 and attenuate the OVA-induced pathological changes in lung tissue. A total of 34 metabolic biomarkers and 84 DEPs were screened from rat lung tissue, which were mainly associated with lipid metabolism, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation, the excessive production of reactive oxygen species (ROS), and lysosome pathway. Besides, SMD could inhibit the myeloid differentiation factor 88 (MyD88)/inhibitor of kappa B kinase (IKK)/nuclear factor-kappa B (NF-κB) signaling pathway to exhibit anti-inflammatory activities.

CONCLUSIONS

SMD exhibited a therapeutic effect on asthma, which possibly be exerted by inhibiting the MyD88/IKK/NF-κB signaling pathway.

Increased di-(2-ethylhexyl) phthalate exposure poses a differential risk for adult asthma clusters

BACKGROUND

DEHP, a common plasticizer known for its hormone-disrupting properties, has been associated with asthma. However, a significant proportion of adult asthma cases are "non-atopic", lacking a clear etiology.

METHODS

In a case-control study conducted between 2011 and 2015, 365 individuals with current asthma and 235 healthy controls from Kaohsiung City were enrolled. The control group comprised individuals without asthma, Type 2 Diabetes Mellitus (T2DM), hypertension, or other respiratory/allergic conditions. The study leveraged asthma clusters (Clusters A to F) established in a prior investigation. Analysis involved the examination of urinary DEHP metabolites (MEHP and MEHHP), along with the assessment of oxidative stress, sphingolipid metabolites, and inflammatory biomarkers. Statistical analyses encompassed Spearman's rank correlation coefficients, multiple logistic regression, and multinomial logistic regression.

RESULTS

Asthma clusters (E, D, C, F, A) exhibited significantly higher ORs of MEHHP exposures compared to the control group. When considering asthma-related comorbidities (T2DM, hypertension, or both), patients without comorbidities demonstrated significantly higher ORs of the sum of primary and secondary metabolites (MEHP + MEHHP) and MEHHP compared to those with asthma comorbidities. A consistent positive correlation between urinary HEL and DEHP metabolites was observed, but a consistent negative correlation between DEHP metabolites and selected cytokines was identified.

CONCLUSION

The current study reveals a heightened risk of MEHHP and MEHP + MEHHP exposure in specific asthma subgroups, emphasizing its complex relationship with asthma. The observed negative correlation with cytokines suggests a new avenue for research, warranting robust evidence from epidemiological and animal studies.

Antibiotic exposure during pregnancy increases risk for childhood atopic diseases: a nationwide cohort study

PURPOSE

The prevalence of atopic diseases has increased in recent decades. A possible link between antibiotic use during pregnancy and childhood atopic disease has been proposed. The aim of this study is to explore the association of antibiotic exposure during pregnancy with childhood atopic diseases from a nationwide, population-based perspective.

METHODS

This was a nationwide population-based cohort study. Taiwan's National Health Insurance Research Database was the main source of data. The pairing of mothers and children was achieved by linking the NHIRD with the Taiwan Maternal and Child Health Database. This study enrolled the first-time pregnancies from 2004 to 2010. Infants of multiple delivery, preterm delivery, and death before 5 years old were excluded. All participants were followed up at least for 5 years. Antenatal antibiotics prescribed to mothers during the pregnancy period were reviewed. Children with more than two outpatient visits, or one admission, with a main diagnosis of asthma, allergic rhinitis, or atopic dermatitis were regarded as having an atopic disease.

RESULTS

A total of 900,584 children were enrolled in this study. The adjusted hazard ratios of antibiotic exposure during pregnancy to childhood atopic diseases were 1.12 for atopic dermatitis, 1.06 for asthma, and 1.08 for allergic rhinitis, all of which reached statistical significance. The trimester effect was not significant. There was a trend showing the higher the number of times a child was prenatally exposed to antibiotics, the higher the hazard ratio was for childhood atopic diseases.

CONCLUSIONS

Prenatal antibiotic exposure might increase the risk of childhood atopic diseases in a dose-dependent manner.

Lung Gene Expression Suggests Roles for Interferon-Stimulated Genes and Adenosine Deaminase Acting against RNA-1 in Pathologic Responses to Diisocyanate

Mechanisms underlying methylene diphenyl diisocyanate (MDI) and other low molecular weight chemical-induced asthma are unclear and appear distinct from those of high molecular weight (HMW) allergen-induced asthma. We sought to elucidate molecular pathways that differentiate asthma-like pathogenic vs nonpathogenic responses to respiratory tract MDI exposure in a murine model. Lung gene expression differences in MDI exposed immune-sensitized and nonsensitized mice vs unexposed controls were measured by microarrays, and associated molecular pathways were identified through bioinformatic analyses and further compared with published studies of a prototypic HMW asthmagen (ovalbumin). Respiratory tract MDI exposure significantly altered lung gene expression in both nonsensitized and immune-sensitized mice, vs controls. Fifty-three gene transcripts were altered in all MDI exposed lung tissue vs controls, with levels up to 10-fold higher in immune-sensitized vs nonsensitized mice. Gene transcripts selectively increased in MDI exposed immune-sensitized animals were dominated by chitinases and chemokines and showed substantial overlap with those increased in ovalbumin-induced asthma. In contrast, MDI exposure of nonsensitized mice increased type I interferon stimulated genes (ISGs) in a pattern reflecting deficiency in adenosine deaminase acting against RNA (ADAR-1), an important regulator of innate, as well as "sterile" or autoimmunity triggered by tissue damage. Thus, MDI-induced changes in lung gene expression were identified that differentiate nonpathogenic innate responses in nonsensitized hosts from pathologic adaptive responses in immune-sensitized hosts. The data suggest that MDI alters unique biological pathways involving ISGs and ADAR-1, potentially explaining its unique immunogenicity/allergenicity.

The effects of vitamin D supplementation on inflammatory biomarkers in patients with asthma: a systematic review and meta-analysis of randomized controlled trials

Background

While the association between vitamin D and several inflammatory biomarkers in asthma patients has been extensively reported, it remains unclear whether supplementation modifies these biomarkers. This review aims to evaluate the impact of vitamin D supplementation on inflammatory biomarkers measured in vivo in individuals with asthma.

Methods

We conducted a systematic review of randomized controlled trials (RCTs) published until November 2022 in six electronic databases evaluating the impact of vitamin D supplementation (any dose, form, administration route, frequency, or duration) compared to placebo in children or adults. The two co-primary outcomes were serum IgE and blood eosinophils reported at the endpoint. Secondary outcomes included other markers of type 2 inflammation (e.g., sputum eosinophils, fractional exhaled nitric oxide, etc.), anti-inflammatory biomarkers (e.g., interleukin (IL)-10, etc.), markers of non-type 2 inflammation (e.g., high-sensitivity C-reactive protein, etc.), and non-specific biomarkers (e.g., macrophages, etc.). Data were aggregated using fixed or random effect models.

Results

Thirteen RCTs (5 in adults, 5 in pediatric patients, and 3 in mixed age groups) testing doses of vitamin D supplementation ranging from 800 to 400,000 IU over periods of 6 weeks to 12 months were included. Eight studies provided data on serum IgE and four on blood eosinophils. As secondary outcomes, three studies reported on sputum eosinophils, four on FeNO, five on serum IL-10, and two on airway IL-10. Compared to placebo, vitamin D supplementation had no significant effect on serum IgE (Mean difference [MD] [95% CI]: 0.06 [-0.13, 0.26] IU/mL), blood eosinophils (MD [95% CI]: - 0.02 [-0.11, 0.07] 103/μL), or FeNO (MD [95% CI]: -4.10 [-10.95, 2.75] ppb) at the endpoint. However, the vitamin D supplementation group showed higher serum IL-10 levels compared to placebo (MD [95% CI]: 18.85 [1.11, 36.59] pg/ml) at the endpoint. Although data could not be aggregated, narrative synthesis suggested no significant effect of supplementation on sputum eosinophils and IL-10 in both sputum and exhaled breath condensate, at the endpoint.

Conclusion

Vitamin D supplementation in individuals with asthma was not associated with lower inflammatory biomarkers related to type 2 inflammation. However, it was significantly associated with higher serum IL-10 compared to placebo.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022365666.

Prenatal polycyclic aromatic hydrocarbon exposure and asthma at age 8-9 years in a multi-site longitudinal study

BACKGROUND AND AIM

Studies suggest prenatal exposure to polycyclic aromatic hydrocarbons (PAHs) may influence wheezing or asthma in preschool-aged children. However, the impact of prenatal PAH exposure on asthma and wheeze in middle childhood remain unclear. We investigated these associations in socio-demographically diverse participants from the ECHO PATHWAYS multi-cohort consortium.

METHODS

We included 1,081 birth parent-child dyads across five U.S. cities. Maternal urinary mono-hydroxylated PAH metabolite concentrations (OH-PAH) were measured during mid-pregnancy. Asthma at age 8-9 years and wheezing trajectory across childhood were characterized by caregiver reported asthma diagnosis and asthma/wheeze symptoms. We used logistic and multinomial regression to estimate odds ratios of asthma and childhood wheezing trajectories associated with five individual OH-PAHs, adjusting for urine specific gravity, various maternal and child characteristics, study site, prenatal and postnatal smoke exposure, and birth year and season in single metabolite and mutually adjusted models. We used multiplicative interaction terms to evaluate effect modification by child sex and explored OH-PAH mixture effects through Weighted Quantile Sum regression.

RESULTS

The prevalence of asthma in the study population was 10%. We found limited evidence of adverse associations between pregnancy OH-PAH concentrations and asthma or wheezing trajectories. We observed adverse associations between 1/9-hydroxyphenanthrene and asthma and persistent wheeze among girls, and evidence of inverse associations with asthma for 1-hydroxynathpthalene, which was stronger among boys, though tests for effect modification by child sex were not statistically significant.

CONCLUSIONS

In a large, multi-site cohort, we did not find strong evidence of an association between prenatal exposure to PAHs and child asthma at age 8-9 years, though some adverse associations were observed among girls.

Mediation of the JNC/ILC2 pathway in DBP-exacerbated allergic asthma: A molecular toxicological study on neuroimmune positive feedback mechanism

BACKGROUND

Dibutyl phthalate (DBP), a commonly used plasticizer, has been found to be strongly linked to a consistently high prevalence of allergic diseases, particularly allergic asthma. Previous animal experiments have demonstrated that exposure to DBP can worsen asthma by triggering the production of calcitonin gene-related peptide (CGRP), a neuropeptide in the lung tissue. However, the precise neuroimmune mechanism and pathophysiology of DBP-exacerbated allergic asthma with the assistance of CGRP remain unclear.

OBJECTIVE

The present study was to investigate the potential pathophysiological mechanism in DBP-exacerbated asthma from the perspective of neural-immune interactions.

METHODS AND RESULTS

C57BL/6 mice were orally exposed to different concentrations (0.4, 4, 40 mg/kg) of DBP for 28 days. They were then sensitized with OVA and nebulized with OVA for 7 consecutive excitations. To investigate whether DBP exacerbates allergic asthma in OVA induced mice, we analyzed airway hyperresponsiveness and lung histopathology. To investigate the activation of JNC and TRPV1 neurons and the release of CGRP by JNC cells, we measured the levels of TRPV1 channels, calcium inward flow, and downstream neuropeptide CGRP. Results showed that TRPV1 expression, inward calcium flux, and CGRP levels were significantly elevated in the lung tissues of the 40DBP + OVA group, suggesting the release of CGRP by JNC cells. To counteract the detrimental effects of DBP mediated by CGRP, we employed olcegepant (also known as BIBN-4096), a CGRP receptor specific antagonist. Results revealed that 40DBP + OVA + olcegepant led to notable decreases in TRPV1, calcium inward flow, and CGRP expression in lung tissues compare with 40DBP + OVA, further supporting the efficacy of olcegepant. Additionally, we also conducted ILC2 flow sorting and observed that neuropeptide CGRP-activated ILC2 cells have a crucial role as key effector cells in DBP-induced neuroimmune positive feedback regulation. Finally, we examined the protein expression of CGRP, GATA3 and P-GATA3, and found that significant upregulations of CGRP and P-GATA3 in the 40DBP + OVA group, suggest that GATA3 acted as a key regulator of CGRP-activated ILC2.

CONCLUSION

The aforementioned studies indicate that exposure to DBP can exacerbate allergic asthma, leading to airway inflammation. This exacerbation occurs through the activation of TRPV1 in JNC, resulting in the release of CGRP. The excessive release of CGRP further promotes the release of Th2 cytokines by inducing the activation of ILC2 through GATA phosphorylation. Consequently, this process contributes to the development of airway inflammation and allergic asthma. The increased production of Th2 cytokines also triggers the production of IgE, which interacts with FcεRI on JNC neurons, thereby mediating neuro-immune positive feedback regulation.

Benralizumab in children with severe eosinophilic asthma: Pharmacokinetics and long-term safety (TATE study)

BACKGROUND

Benralizumab is an anti-interleukin-5 receptor α monoclonal antibody approved as an add-on maintenance treatment for patients with uncontrolled severe asthma. Prior Phase 3 studies have evaluated benralizumab in patients aged ≥12 years with severe uncontrolled asthma. The TATE study evaluated the pharmacokinetics (PK), pharmacodynamics (PD), and safety of benralizumab treatment in children.

METHODS

TATE was an open-label, Phase 3 study of benralizumab in children aged 6-11 years from the United States and Japan (plus participants aged 12-14 years from Japan) with severe eosinophilic asthma. Participants received benralizumab 10/30 mg according to weight (<35/≥35 kg). Primary endpoints included maximum serum concentration (Cmax ), clearance, half-life (t1/2 ), and blood eosinophil count. Clearance and t1/2 were derived from a population PK (popPK) analysis. Safety and tolerability were also assessed.

RESULTS

Twenty-eight children aged 6-11 years were included, with an additional two participants from Japan aged 12-14 years also included in the popPK analysis. Mean Cmax was 1901.2 and 3118.7 ng/mL in the 10 mg/<35 kg and 30 mg/≥35 kg groups, respectively. Clearance was 0.257, and mean t1/2 was 14.5 days. Near-complete depletion of blood eosinophils was shown across dose/weight groups. Exploratory efficacy analyses found numerical improvements in mean FEV1 , mean ACQ-IA, patient/clinician global impression of change, and exacerbation rates. Adverse events occurred in 22/28 (78.6%) of participants; none led to discontinuation/death.

CONCLUSION

PK, PD, and safety data support long-term benralizumab in children with severe eosinophilic asthma, and were similar to findings in adolescents and adults.

TRIAL REGISTRATION

ClinicalTrials.gov-ID: NCT04305405.

Role of inflammatory lipid and fatty acid metabolic abnormalities induced by plastic additives exposure in childhood asthma

Lipid metabolism play an essential role in occurrence and development of asthma, and it can be disturbed by phthalate esters (PAEs) and organophosphate flame retardants (OPFRs). As a chronic inflammatory respiratory disease, the occurrence risk of childhood asthma is increased by PAEs and OPFRs exposure, but it remains not entirely clear how PAEs and OPFRs contribute the onset and progress of the disease. We have profiled the serum levels of PAEs and OPFRs congeners by liquid chromatography coupled with mass spectrometry, and its relationships with the dysregulation of lipid metabolism in asthmatic, bronchitic (acute inflammation) and healthy (non-inflammation) children. Eight PAEs and nine OPFRs congeners were found in the serum of children (1 - 5 years old) from Shenzhen, and their total median levels were 615.16 ng/mL and 17.06 ng/mL, respectively. Moreover, the serum levels of mono-methyl phthalate (MMP), tri-propyl phosphate (TPP) and tri-n-butyl phosphate (TNBP) were significant higher in asthmatic children than in healthy and bronchitic children as control. Thirty-one characteristic lipids and fatty acids of asthma were screened by machine-learning random forest model based on serum lipidome data, and the alterations of inflammatory characteristic lipids and fatty acids including palmitic acids, 12,13-DiHODE, 14,21-DiHDHA, prostaglandin D2 and LysoPA(18:2) showed significant correlated with high serum levels of MMP, TPP and TNBP. These results imply PAEs and OPFRs promote the occurrence of childhood asthma via disrupting inflammatory lipid and fatty acid metabolism, and provide a novel sight for better understanding the effects of plastic additives on childhood asthma.

Echinochrome exhibits anti-asthmatic activity through the suppression of airway inflammation, oxidative stress, and histopathological alterations in ovalbumin-induced asthma in BALB/c mice

Asthma is a chronic pulmonary disease with marked infiltrating inflammatory cells and reduced respiratory performance. Echinochrome (Ech) is a dark-red pigment isolated from the sea urchin spines, shells, and ova. It has antioxidant, antimicrobial, and anti-inflammatory properties, but whether it can be used in asthma treatment has yet to be investigated. In this research, we aimed to study the inhibitory actions of Ech on allergic asthma symptoms in mice. Mice were divided into 4 groups (n = 8 for each): control, ovalbumin-challenged, and Ech-treated (0.1 and 1 mg/kg). At the end of the experiment, nasal scratching, lung oxidative stress, airway inflammation, and remodeling were assessed. In ovalbumin-challenged BALB/C mice, treatment with Ech significantly decreased nasal scratching, lung oxidative stress, inflammatory cell infiltration, mucus hyperproduction and hyperplasia of goblet cells, IgE levels, and inflammatory cytokines. It also inhibited NF-κB phosphorylation. This is the first study to investigate the immunomodulatory effect of Ech against allergic asthma in mice. According to our findings, we imply that Ech may be utilized as a treatment for allergic asthma.

Therapeutic potential of flavonoids in ovalbumin induced asthma in mice model

OBJECTIVES

Desmodium triquetrum DC (Fabaceae) is a plant commonly used in Indian traditional medicine to treat allergies. Asthma is a severe condition, with an estimated 300 million deaths annually, which could increase to 400 million by 2025. Flavonoids, a class of compounds found in many plants, have been found to have beneficial effects in treating asthma. In this study, researchers focused on three flavonoids, Baicalein, Naringin, and Neohesperidin, derived from Desmodium triquetrum DC, to investigate their potential as a treatment for asthma.

METHODS

The study used an aerosolized ovalbumin-induced asthma model to evaluate the effects of the flavonoids on various substances in bronchoalveolar lavage fluid, including total differential leukocyte, nitrite, nitrate, TNF, IL-4, and IL-13. The researchers also measured the levels of myeloperoxidase and malondialdehyde in the lungs.

RESULTS

The results showed that ovalbumin-induced airway hyper-responsiveness led to a significant increase in pro-inflammatory cytokine levels. However, the flavonoids significantly decreased the severity of airway inflammation. Histopathology results also supported the effectiveness of the flavonoids. These findings suggest that these flavonoids could be a supplementary and alternative treatment for asthma by inhibiting the pro-inflammatory pathway.

CONCLUSIONS

The findings suggest that the isolated compounds have the potential to act cumulatively to decrease the levels of the tested cytokines, normalize eosinophil and activated lymphocyte counts, and significantly reduce MPO and MDA. This indicates a possible respiratory mechanism of action for the drugs.

Oxidative stress-mediated activation of FTO exacerbates impairment of the epithelial barrier by up-regulating IKBKB via N6-methyladenosine-dependent mRNA stability in asthmatic mice exposed to PM2.5

In order to comprehend the underlying mechanisms contributing to the development and exacerbation of asthma resulting from exposure to fine particulate matter (PM2.5), we established an asthmatic model in fat mass and obesity-associated gene knockdown mice subjected to PM2.5 exposure. Histological analyses using hematoxylin-eosin (HE) and Periodic Acid-Schiff (PAS) staining revealed that the down-regulation of the fat mass and obesity-associated gene (Fto) expression significantly ameliorated the pathophysiological alterations observed in asthmatic mice exposed to PM2.5. Furthermore, the down-regulation of Fto gene expression effectively attenuated damage to the airway epithelial barrier. Additionally, employing in vivo and in vitro models, we elucidated that PM2.5 modulated FTO expression by inducing oxidative stress. Asthmatic mice exposed to PM2.5 exhibited elevated Fto expression, which correlated with increased levels of reactive oxygen species. Similarly, when cells were exposed to PM2.5, FTO expression was up-regulated in a ROS-dependent manner. Notably, the administration of N-acetyl cysteine successfully reversed the PM2.5-induced elevation in FTO expression. Concurrently, we performed transcriptome-wide Methylated RNA immunoprecipitation Sequencing (MeRIP-seq) analysis subsequent to PM2.5 exposure. Through the implementation of Gene Set Enrichment Analysis and m6A-IP-qPCR, we successfully identified inhibitor of nuclear factor kappa B kinase subunit beta (IKBKB) as a target gene regulated by FTO. Interestingly, exposure to PM2.5 led to increased expression of IKBKB, while m6A modification on IKBKB mRNA was reduced. Furthermore, our investigation revealed that PM2.5 also regulated IKBKB through oxidative stress. Significantly, the down-regulation of IKBKB effectively mitigated epithelial barrier damage in cells exposed to PM2.5 by modulating nuclear factor-kappa B (NF-κB) signaling. Importantly, we discovered that decreased m6A modification on IKBKB mRNA facilitated by FTO enhanced its stability, consequently resulting in up-regulation of IKBKB expression. Collectively, our findings propose a novel role for FTO in the regulation of IKBKB through m6A-dependent mRNA stability in the context of PM2.5-induced oxidative stress. Therefore, it is conceivable that the utilization of antioxidants or inhibition of FTO could represent potential therapeutic strategies for the management of asthma exacerbated by PM2.5 exposure.

Safety and efficacy of benralizumab in elderly subjects with severe asthma

INTRODUCTION

The prevalence of asthma in adults >65 years old is approximately 12-14%, and 10% have severe asthma. A higher mortality rate is observed in subjects with asthma >65 years old and especially >80 years old.

OBJECTIVE

To analyze the effectiveness and safety of at least three doses of benralizumab in a subgroup of elderly subjects (>65 years old) with uncontrolled severe eosinophilic asthma in real-life conditions.

METHODS

This was a retrospective multicenter study (AUTOBENRA study) conducted in 9 hospitals that included 72 patients aged >18 years old with uncontrolled severe asthma based on the Spanish Asthma Guidelines who were treated with at least three doses of benralizumab, self-administered at home since before April 30, 2021. The recruitment period ended on October 1, 2021. Written consent was obtained before the study commencement. In this subanalysis, we compared the results between patients >65 years old and patients <65 years old.

RESULTS

A total of 72 subjects with severe asthma were screened, and 54 were included (MD: 57.3 ± 10 years old). There were 12 subjects aged >65 years old [MD: 69.8 ± 4.3 years old (minimum: 65 years old; maximum: 83 years old)]. Subjects >65 years old experienced statistically significant improvement in lung function, ACT and mini-AQLQ with benralizumab. Additionally, 9 patients (75%) experienced no asthma exacerbation (p = 0.0047), half (3/6) were able to stop OCS (p = 0.08), and no adverse effects with benralizumab were reported during the 20 months of follow-up.

CONCLUSIONS

In patients aged >65 years old, benralizumab was an effective and safe therapy for severe eosinophilic asthma in our study, with no significant differences from the younger subgroup. This is especially important since they are a group with numerous comorbidities, medications and worse quality of life.

Effectiveness of omalizumab across different dosing regimens in patients with moderate-to-severe allergic asthma

For patients with moderate-to-severe persistent allergic asthma, omalizumab is approved for subcutaneous administration according to a recommended dosing table based on weight and total immunoglobulin E (IgE) level. The aim of this analysis was to assess asthma outcomes including quality of life in patients with allergic asthma initiated on omalizumab in the PROSPERO trial; patients were stratified by where their IgE and body weight fell on the approved dosing table. Patient groups were defined as Inside Dosing Table: patients whose IgE and weight fell within the approved dosing table (n = 506); Insufficient Data to Recommend a Dose: patients who fell into the section of the approved dosing table where not enough clinical data were available to make dosing recommendations (n = 72); and Outside Dosing Table: patients who fell outside the approved dosing table due to baseline IgE and/or weight (n = 209). Overall, asthma and quality of life outcomes were improved after omalizumab initiation for both patients who fall within the recommended dosing table or those who fall outside the recommended dosing table. Our results suggest that omalizumab treatment may be effective in a wide range of patients with moderate-to-severe allergic asthma. ClinicalTrials.gov identifier NCT01922037.

The combined effect of oxidative stress and TRPV1 on temperature-induced asthma: Evidence in a mouse model

Temperature is one of the possible activators for asthma. As global warming continues, the health hazard of high temperatures is increasing. It is unclear, nevertheless, how high temperatures affect asthma. The research aims to examine how asthma is affected by high temperatures and underlying molecular mechanisms. The BALB/c mice were adopted in a model of asthma. The mice were exposed at 24 °C, 38 °C and 40 °C for 4h on weekdays from day 1 to day 30. After the experiment, the lung function was measured in vivo, and then serum protein, pulmonary inflammation and immunohistochemistry assay was assessed in vitro. As the temperature increased from 24 °C to 40 °C, there was a significant increase in serum protein, while there is no discernible difference in serum protein of OVA-sIgE and OVA-sIgG between the OVA (38 °C) group and OVA (24 °C) group. The immunohistochemistry assay showed a change in the pro-inflammatory cytokines. The histopathological analysis exhibited the change of airway structure after high-temperature exposure, especially for exposure at 40 °C. The results of signals protein showed a remarkable rise of TRPV1 for OVA+40 °C. Our results revealed that high temperatures may make asthmatic airway dysfunction severe, and the higher the temperature, the more serious asthma. The oxidative stress and TRPV1 receptor can be a potential drug target for asthma. It will provide a new tool for precision medicine in asthma.

Jiangqi Pingxiao formula regulates dendritic cell apoptosis in an autophagy-dependent manner through the AMPK/mTOR pathway in a murine model of OVA-induced asthma

ETHNOPHARMACOLOGICAL RELEVANCE

Allergic asthma is a recurring respiratory condition that typically manifests during childhood or adolescence. It is characterized by a dominant type II immune response triggered by the identification and capturing of inhaled allergens by dendritic cells (DCs). Jiangqi Pingxiao Formula (JQPXF), a prescription medicine used for the treatment of pediatric asthma, has been clinically proven to be both safe and effective. However, its mechanism of action in the treatment of asthma has not been fully been fully elucidated. Recent research suggests that several natural compounds have the potential to target dendritic cells (DCs) and alleviate ovalbumin (OVA)-induced asthma, which may also be found within JQPXF.

AIM OF THE STUDY

This study aimed to elucidate the effect of JQPXF on OVA-induced asthma model and its molecular mechanism targeting DCs.

MATERIALS AND METHODS

The main constituents of JQPXF were analyzed by ultra performance liquid chromatography (UPLC). An asthma model was established by OVA. Hematoxylin-eosin staining and measurement of respiratory function was used to evaluate the treatment effect of JQPXF on asthmatic mice. Cytokine (IL-5, IL-13 and IgE) concentrations were determined by enzyme-linked immunosorbent assay (ELISA). Flow cytometry was employed to evaluate inflammatory cell infiltration (T helper 2 cells and DCs) in vivo and DC survival in vivo and vitro. Western blot and immunofluorescence were used to verify the molecular mechanisms.

RESULTS

The results suggest that JQPXF can ameliorate pathological conditions and improve lung function in asthmatic mice, as well as the Th2 cells. Treatment with JQPXF significantly reduced the number of DCs and increased the number of Propidium iodide+ (PI) DCs. Furthermore, JQPXF upregulated protein levels of the pro-apoptotic factors Cleaved-caspase-3 and Bax, while downregulating the anti-apoptotic factor Bcl-2. Simultaneously, JQPXF increased autophagy levels by facilitating p62 degradation and promoting translation from LC3B I to LC3B II of DCs in vitro, as well as reducing the integrated optical density (IOD) of p62 within the CD11c-positive area in the lung. 3-Methyladenine (3-MA) was used to block autophagic flux and the apoptotic effect of JQPXF on DCs was abolished in vitro, with the number of DCs decreased by JQPXF being reversed in vivo. We further investigated the upstream key regulator of autophagy, the AMPK/mTOR pathway, and found that JQPXF increased AMPK phosphorylation while decreasing mTOR phosphorylation levels. Additionally, we employed Compound C (CC) as an AMPK inhibitor to inhibit this signaling pathway, and our findings revealed that both autophagic flux and apoptotic levels in DCs were abolished in vitro.

CONCLUSIONS

In summary, we have demonstrated that JQPXF could alleviate type II inflammation in an asthmatic model by promoting the apoptosis of DCs through an autophagy-dependent mechanism, achieved by regulating the AMPK/mTOR signaling pathway.

Anti-inflammation of LZTFL1 knockdown in OVA-induced asthmatic mice: Through ERK/GATA3 signaling pathway

Asthma is a common chronic respiratory disease characterized by Th2-type inflammation in the airways. Leucine zip transcription factor-like 1 (LZTFL1) has been implicated in the regulation of Th2-related factors. The knockdown of LZTFL1 resulted in decreased levels of IL-4, IL-5, and IL-13. We hypothesize that LZTFL1 may have an effect on asthma. We established an acute asthmatic mouse model using the Ovalbumin (OVA) sensitization, and we found that LZTFL1 expression was upregulated in OVA-induced CD4 + T cells. Mice challenged with OVA were administered 5 × 107 TU of lentivirus via tail vein injection. LZTFL1 knockdown reversed the frequency of sneezing and nose rubbing in OVA mice. LZTFL1 knockdown reduced inflammatory cell infiltration, reduced goblet cell numbers, and mitigated collagen deposition in lung tissue. LZTFL1 knockdown decreased the levels of OVA-specific IgE, IL-4, IL-5, and IL-13 in alveolar lavage fluid of asthmatic mice. Furthermore, LZTFL1 knockdown inhibited the aberrant activation of MEK/ERK signaling pathway in asthmatic mice. GATA binding protein 3 (GATA3) is an essential transcription factor in Th2 differentiation. Flow cytometry results revealed that LZTFL1 knockdown reduced the number of GATA3 + CD4 + Th2 cells, while it did not affect the stability of GATA3 mRNA. This may be attributed to ERK signaling which stabilized GATA3 by preventing its ubiquitination and subsequent degradation. In conclusion, LZTFL1 knockdown attenuates inflammation and pathological changes in OVA-induced asthmatic mice through ERK/GATA3 signaling pathway.

Dual biologics therapy in a patient with severe asthma and chronic urticaria: a case report and review of the literature

INTRODUCTION

The data on the use of dual biologics are scant, but a topic of current interest.

CASE STUDY

In this report, the treatment regimen of a patient with two T helper 2 pathway-related comorbidities, severe asthma, and chronic spontaneous urticaria, was presented.

RESULTS

Both urticaria and asthma symptoms of the patient could not be controlled entirely with monotherapy while both diseases could be controlled after omalizumab-mepolizumab dual treatment. No adverse events were observed after 6 months of dual biologics use.

CONCLUSION

This report supports other publications in the literature involving the use of dual biologics and provides a summary of the literature.

Investigation analysis of the acute asthma risk factor and phenotype based on relational analysis with outdoor air pollutants in Xi'an, China

Asthma is a common chronic heterogeneous disease. Outdoor air pollutants are an important cause of acute asthma. Until now, the association between the risk of acute asthma and outdoor air pollutants is unclear. And the relationship between the different phenotypes of asthma and outdoor air pollutants has not been reported. Thus, an analysis of the association between outdoor air pollutants and daily acute asthma inpatient and outpatient visits in Xi'an, China, from January 1 to December 31, 2018, was conducted. A total of 3395 people were included in the study. The statistical analysis and relational analysis based on the logistic regression were used for illustrating the relatedness of the acute asthma risk factor and phenotype with outdoor air pollutants, while the age, gender, pollen peak and non-pollen peak periods, high type 2 (T2) asthma and non-high T2 asthma were also stratified. Results showed that particulate matter with particle size below 10 μm and 2.5 μm (PM10 and PM2.5), sulfur dioxide(SO2), nitrogen dioxide(NO2), and carbon monoxide(CO) increase the risk of acute asthma and that air pollutants have a lagged effect on asthma patients. PM10, NO2, CO, and Ozone (O3) are associated with an increased risk of acute attacks of high T2 asthma. PM10, PM2.5, SO2, NO2 and CO are associated with an increased risk of acute asthma in males of 0-16 years old. PM10 and PM2.5 are more harmful to asthma patients with abnormal lung function.

Combined exposure of MAHs and PAHs enhanced amino acid and lipid metabolism disruption in epithelium leading asthma risk

Monoaromatic hydrocarbons (MAHs) and polycyclic aromatic hydrocarbons (PAHs) are ubiquitous air pollutants from industry, with multiple adverse effects on respiratory system. However, the underlying mechanisms of their mixture to induce asthma is still unclear. Here, we examined mixture of 8 MAHs, mixture of 16 PAHs and a total mixture (MIX) on human bronchial epithelial (16-HBE) cells. Exposure to MIX resulted in increased expressions of asthma alarm cytokines (TSLP, IL-25 and IL-33), indicating potential asthma risk. Exposure to MIX led to significant upregulation of transcriptional level of oxidative stress and inflammation biomarkers through aryl hydrocarbon receptor activation, including SOD-2, NQO-1, IL-1β, IL-6 and IL-8 with 3.1, 19.9, 3.5, 23.4, 18.7, 28.1-fold change, indicated asthma related epithelial cell lesions. A total of 25, 49 and 59 differential metabolites were identified in cells response to MAH, PAH and MIX exposure, respectively, and enrichment analysis demonstrated MIX exposure disturbing alanine, aspartate and glutamate metabolism, glutathione metabolism, methionine metabolism and sphingolipid metabolism, involved in antioxidative defense and inflammation response. Combined exposure of MAHs and PAHs may result in increased toxic risks, and provide evidence to asthma onset and deterioration.

Changes in industrial air pollution and the onset of childhood asthma in Quebec, Canada

Ambient air pollution has been associated with asthma onset and exacerbation in children. Whether improvement in air quality due to reduced industrial emissions has resulted in improved health outcomes such as asthma in some localities has usually been assessed indirectly with studies on between-subject comparisons of air pollution from all sources and health outcomes. In this study we directly assessed, within small areas in the province of Quebec (Canada), the influence of changes in local industrial fine particulate matter (PM2.5), nitrogen dioxide (NO2), and sulfur dioxide (SO2) concentrations, on changes in annual asthma onset rates in children (≤12 years old) with a longitudinal ecological design. We identified the yearly number of new cases of childhood asthma in 1282 small areas (census tracts or local community service centers) for the years 2002, 2004, 2005, 2006, and 2015. Annual average concentrations of industrial air pollutants for each of the geographic areas, and three sectors (i.e., pulp and paper mills, petroleum refineries, and metal smelters) were estimated by the Polair3D chemical transport model. Fixed-effects negative binomial models adjusted for household income were used to assess associations; additional adjustments for environmental tobacco smoke, background pollutant concentrations, vegetation coverage, and sociodemographic characteristics were conducted in sensitivity analyses. The incidence rate ratios (IRR) for childhood asthma onset for the interquartile increase in total industrial PM2.5, NO2, and SO2 were 1.016 (95% confidence interval, CI: 1.006-1.026), 1.063 (1.045-1.090), and 1.048 (1.031-1.080), respectively. Positive associations were also found with pollutant concentrations from most individual sectors. Results suggest that changes in industrial pollutant concentrations influence childhood asthma onset rates in small localities.

Resolvin and lipoxin metabolism network regulated by Hyssopus Cuspidatus Boriss extract in asthmatic mice

Resolvin (Rv) and lipoxin (Lx) play important regulative roles in the development of several inflammation-related diseases. The dysregulation of their metabolic network is believed to be closely related to the occurrence and development of asthma. The Hyssopus Cuspidatus Boriss extract (SXCF) has long been used as a treatment for asthma, while the mechanism of anti-inflammatory and anti-asthma action targeting Rv and Lx has not been thoroughly investigated. In this study, we aimed to investigate the effects of SXCF on Rv, Lx in ovalbumin (OVA)-sensitized asthmatic mice. The changes of Rv, Lx before and after drug administration were analyzed based on high sensitivity chromatography-multiple response monitoring (UHPLC-MRM) analysis and multivariate statistics. The pathology exploration included behavioral changes of mice, IgE in serum, cytokines in BALF, and lung tissue sections stained with H&E. It was found that SXCF significantly modulated the metabolic disturbance of Rv, Lx due to asthma. Its modulation effect was significantly better than that of dexamethasone and rosmarinic acid which is the first-line clinical medicine and the main component of Hyssopus Cuspidatus Boriss, respectively. SXCF is demonstrated to be a potential anti-asthmatic drug with significant disease-modifying effects on OVA-induced asthma. The modulation of Rv and Lx is a possible underlying mechanism of the SXCF effects.

Real-World Effectiveness of Statin Therapy in Adult Asthma

BACKGROUND

Blood lipids affect airway inflammation in asthma. Although several studies have suggested anti-inflammatory effects of statins on asthmatic airways, further studies are needed to clarify the long-term effectiveness of statins on asthma control and whether they are an effective treatment option.

OBJECTIVE

To evaluate the long-term effectiveness of statins in the chronic management of adult asthma in real-world practice.

METHODS

Electronic medical record data spanning 28 years, collected from the Ajou University Medical Center in Korea, were used to conduct a retrospective study. Clinical outcomes were compared between patients with asthma who had maintained statin use (the statin group) and those not taking statins, whose blood lipid tests were always normal (the non-statin group). We performed propensity score matching and calculated hazard ratios with 95% CIs using the Cox proportional hazards model. Severe asthma exacerbation was the primary outcome; asthma exacerbation, asthma-related hospitalization, and new-onset type 2 diabetes mellitus and hypertension were secondary outcomes.

RESULTS

After 1:1 propensity score matching, the statin and non-statin groups each included 545 adult patients with asthma. The risk of severe asthma exacerbations and asthma exacerbations was significantly lower in the statin group than in the non-statin group (hazard ratios [95% CI] = 0.57 [0.35-0.90] and 0.71 [0.52-0.96], respectively). There were no significant differences in the risk of asthma-related hospitalization or new-onset type 2 diabetes mellitus or hypertension between groups (0.76 [0.53-1.09], 2.33 [0.94-6.59], and 1.71 [0.95-3.17], respectively).

CONCLUSION

Statin use is associated with a lower risk of asthma exacerbation, with better clinical outcomes in adult asthma.

Maternal exposure to pyrethroid insecticides during pregnancy and respiratory allergy symptoms among children participating in the Venda Health Examination of Mothers, Babies and their Environment (VHEMBE)

BACKGROUND

Pyrethroid insecticides use for indoor residual spraying (IRS) in malaria-endemic areas results in high levels of exposure to local populations. Pyrethroids may cause asthma and respiratory allergies but no prior study has investigated this question in an IRS area.

METHODS

We measured maternal urinary concentrations of pyrethroid metabolites (cis-DBCA, cis-DCCA, trans-DCCA, 3-PBA) in samples collected at delivery from 751 mothers participating in the Venda Health Examination of Mothers, Babies, and their Environment (VHEMBE), a birth cohort study based in Limpopo, South Africa. At 3.5-year and 5-year follow-up visits, caregivers of 647 and 620 children, respectively, were queried about children's respiratory allergy symptoms based on validated instruments. We applied marginal structural models for repeated outcomes to estimate associations between biomarker concentrations and asthma diagnosis as well as respiratory allergy symptoms at ages 3.5 and 5 years.

RESULTS

We found that a10-fold increase in maternal urinary cis-DCCA, trans-DCCA and 3-PBA concentrations were associated with more than a doubling in the risk of doctor-diagnosed asthma (cis-DCCA: RR = 2.1, 95% CI = 1.3, 3.3; trans-DCCA: RR = 2.1, 95% CI = 1.1, 3.9; 3-PBA: RR = 2.4, 95% CI = 1.0, 5.8) and an about 80% increase in the risk of wheezing or whistling in the chest (cis-DCCA: RR = 1.8, 95% CI = 1.1, 3.0; trans-DCCA: RR = 1.7, 95% CI = 1.1, 2.6; 3-PBA: RR = 1.8, 95% CI = 1.0, 3.3) and suspected asthma (cis-DCCA: RR = 1.8, 95% CI = 1.1, 3.1; trans-DCCA: RR = 1.8, 95% CI = 1.1, 2.8). We also observed that higher concentrations of cis-DBCA and 3-PBA were related to increases in the risks of dry cough at night (RR = 3.5, 95% CI = 1.3, 9.5) and seasonal rhinoconjunctivitis (RR = 2.0, 95% CI = 1.1, 3.9), respectively.

CONCLUSION

Maternal exposure to pyrethroids may increase the risk of asthma and other respiratory allergy symptoms among preschool children from an IRS area.

Qufeng Xuanbi Formula inhibited benzo[a]pyrene-induced aggravated asthma airway mucus secretion by AhR/ROS/ERK pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Excessive secretion of airway mucus may be an important pathological factor of air pollution-induced acute asthma attacks. Treatment of airway mucus hypersecretion improves asthma aggravated by air pollutants. Qufeng Xuanbi Formula (QFXBF) has been used to treat asthma for more than 30 years. However, whether QFXBF inhibits asthmatic mucus secretion exacerbated by air pollutants has not yet been established.

AIM OF THE STUDY

This study aimed to evaluate the effect of QFXBF on airway mucus secretion and the mechanism of action in an air pollutant benzo[a]pyrene (BaP)-induced mouse model of aggravated asthma.

MATERIALS AND METHODS

Ovalbumin (OVA) and BaP co-exposure were used to establish the aggravated asthma model. The average enhanced pause (Penh), serum OVA-specific IgE, and changes in lung histopathology were determined. 16HBE cells exposed to BaP, treatment with QFXBF, arylhydrocarbon receptor (AhR) signal antagonist SR1, reactive oxygen species (ROS) antagonist NAC, or extracellular signal-regulated kinase (ERK1/2) signal antagonist U0126 were established to investigate the effect of QFXBF on BaP-induced mucus secretion and its target. The mRNA and protein expression levels of MUC5AC in the lung tissue and 16HBE cells were examined. We also studied the effect of QFXBF on ROS production. Finally, the protein expression of AhR, phospho-extracellular signal-regulated kinases (p-ERK1/2), and ERK1/2 in 16HBE cells and lung tissues was determined by western blotting.

RESULTS

Administration of QFXBF significantly alleviated the pathological symptoms, including Penh, serum OVA-specific IgE, and changes in lung histopathology in a BaP-induced mouse model of aggravated asthma. QFXBF inhibited MUC5AC expression in asthmatic mice and 16HBE cells exposed to BaP. ROS production, AhR expression, and ERK1/2 phosphorylation were significantly increased in BaP-induced asthmatic mice and 16HBE cells. Signaling pathway inhibitors StemRegenin 1 (SR1), NAC, and U0126 significantly inhibitedBaP-induced MUC5AC expression in 16HBE cells. SR1 reversed Bap-induced ROS production and ERK activation, and NAC inhibited Bap-induced ERK activation. In addition, QFXBF regulated AhR signaling, inhibited ROS production, reversed ERK activation, and downregulated mucus secretion to improve asthma aggravated by air pollutant BaP.

CONCLUSIONS

QFXBF can ameliorate mucus secretion in BaP-induced aggravated asthmatic mice and 16HBE cells, and the specific mechanism may be related to the inhibition of the AhR/ROS/ERK signaling pathway.

Unveiling the potent effect of vitamin D: harnessing Nrf2/HO-1 signaling pathways as molecular targets to alleviate urban particulate matter-induced asthma inflammation

BACKGROUND

Asthma is the most common allergic disease characterized by an inflammatory response in the airways. Mechanismly, urban particulate matter (PM) is the most widely air pollutant associated with increased asthma morbidity and airway inflammation. Current research found that vitamin D is an essential vitamin with anti-inflammatory, antioxidant and other medical efficacy. Inadequate or deficient vitamin D often leads to the pathogenesis and stability of asthma. NGF exacerbates airway inflammation in asthma by promoting smooth muscle cell proliferation and inducing the Th2 immune response. Activation of the Nrf2/HO-1 signaling pathway can exert a protective effect on the inflammatory response in bronchial asthma. However, the specific mechanism of this pathway in PM-involved asthmatic airway smooth muscle cells remains unclear.

METHODS

Mice were sensitized and challenged with Ovalbumin (OVA) to establish an asthma model. They were then exposed to either PM, vitamin D or a combination of both, and inflammatory responses were observed. Including, acetylcholine stimulation at different concentrations measured airway hyperresponsiveness in mice. Bronchoalveolar lavage fluid (BALF) and serum were collected for TNF-α, IL-1β, IL-6, and Nerve growth factor (NGF) analysis. Additionally, lung tissues underwent histopathological examination to observe alveolar structure and inflammatory cell infiltration. Specific ELISA kits were utilized to determine the levels of the inflammatory factors TNF-α, IL-1β, IL-6, and Nerve growth factor (NGF). Nrf2/HO-1 signaling pathways were examined by western blot analysis. Meanwhile, we constructed a cell system with low HO-1 expression by lentiviral transfection of airway smooth muscle cells. The changes of Nrf2, HO-1, and NGF were observed after the treatment of OVA, PM, and Vit D were given.

RESULTS

The in vivo results showed that vitamin D significantly alleviated pathological changes in lung tissue of PM-exposed mice models. Mechanismly, vitamin D decreased substantial inflammatory cell infiltration in lung tissue, as well as the number of inflammatory cells in BALF. Furthermore, vitamin D reduced the heightened inflammatory factors including of TNF-α, IL-1β, IL-6, and NGF caused by PM exposure, and triggered the activity of nucleus Nrf2 and HO-1 in PM-exposed asthmatic mice. Notably, knockdown HO-1 weakens the Vitamin D- mediated inhibition to pollution toxicity in asthma. Importantly, in vitro experiments on OVA-stimulated mice airway smooth muscle cells, the results showed that OVA and PM, respectively, reduced Nrf2/HO-1 and increased NGF's expression, while vitamin D reversed the process. And in the HO-1 knockdown cell line of Lenti-si-HO-1 ASMCs, OVA and PM reduced Nrf2's expression, while HO-1 and NGF's expression were unchanged.

CONCLUSIONS

The above results demastrate that vitamin D downregulated the inflammatory response and the expression of NGF by regulating the Nrf2/HO-1 signaling pathways in airway smooth muscle cells, thereby showing potent anti-inflammatory activity in asthma.

Protective effect of Achyranthes aspera against compound 48/80, histamine and ovalbumin-induced allergic disorders in murine model

BACKGROUND

Achyranthes aspera L. (family Amaranthaceae) is a plant species valued in Ayurveda for the treatment of respiratory ailments. Scientific validation of its antiallergic potential was aimed.

METHODS AND RESULTS

Three extracts of A. aspera [aqueous (AaAq), hydroalcoholic (AaHA), ethanolic (AaEt)] were evaluated for their potency against C48/80-induced anaphylaxis in mice at 200 mg/kg BW oral dose. The effective dose of the most potent extract was determined through its effect on C48/80-induced anaphylaxis, and was further analyzed through its effect on mast cell degranulation, histamine-induced bronchospasm and ovalbumin (OVA)-induced asthma in a murine model. Among the three extracts, AaAq was found to be most potent at 200 mg/kg BW. AaAq 400 (400 mg/kg BW) was found to be the most effective dose in terms of inhibition of mortality and histamine level. AaAq 400 prevented the peritoneal and mesenteric mast cells from undergoing morphological changes due to degranulation induced by C48/80. Further, AaAq 400 delayed pre-convulsive time in histamine-induced bronchospasm. In the OVA-induced asthma model, AaAq 400 inhibited the level of inflammatory cell count in blood, bronchoalveolar lavage fluid and peritoneal fluid of mice. The Th2 cytokines (IL-4, IL-5, IL-13), TGF-β and OVA-specific IgE were also reduced as evaluated by ELISA. Also, significant reduction in IL-5 (an eosinophilia indicator) transcript abundance and lung inflammatory score was observed. AaAq was safe up to 4000 mg/kg BW.

CONCLUSIONS

Thus AaAq 400 possesses significant antiallergic potential and acts via attenuation of C48/80-induced anaphylaxis and inhibition of mast cell degranulation. It reduces pre-convulsive dyspnea in histamine-induced bronchospasm and Th2 cytokines in asthmatic mice.

Preparation of Budesonide-Loaded Liposomal Nanoparticles for Pulmonary Delivery and Their Therapeutic Effect in OVA-Induced Asthma in Mice

Purpose

Inhaled corticosteroids, including budesonide (BUD), are widely employed for the treatment of asthma. However, the frequent use of corticosteroids is associated with numerous adverse effects and poses challenges to ongoing drug therapy and patient adherence. Budesonide liposomal nanoparticles (BUD-LNPs) were developed to improve the bioavailability of the drug and thereby improve the effectiveness of asthma treatment.

Methods

BUD-LNPs were prepared via thin-film hydration, and the characterizations, stability, and in vitro release of BUD-LNPs were studied. In vitro cellular uptake was observed by laser-scanning confocal microscope (LSCM) and flow cytometry. And the in vitro anti-inflammatory activity of BUD-LNPs was evaluated by measuring the expression of pro-inflammatory cytokines in activated macrophages. Besides, the accumulation time in the lung of drugs delivered via liposomal carriers and free drugs was compared in vivo. And the in vivo therapeutic efficacy of BUD-LNPs was assessed in OVA-induced asthmatic mice. Finally, in vivo biosafety assessment was performed.

Results

The particle size, PDI, and zeta potential of BUD-LNPs were 127.63±1.33 nm, 0.27±0.02, and 3.33±0.13 mV, respectively. BUD-LNPs exhibited excellent biosafety and anti-inflammatory activity in vitro. Furthermore, compared with the free drugs, the utilization of liposomal nano-vehicles for drugs delivery could effectively extend the duration of drugs accumulation in the pulmonary system. Additionally, treatment with BUD-LNPs alleviated airway hyperresponsiveness, reduced airway mucus secretion, and mitigated pulmonary inflammation in OVA-induced asthmatic mice. And the BUD-LNPs demonstrated superior therapeutic efficacy compared to free BUD.

Conclusion

BUD-LNPs was successfully prepared with excellent stability and sustained release for 24 h in vitro. The data of anti-inflammatory activity, asthma therapeutic effects and safety studies indicated that drug delivery mediated by liposomal nano-vehicles was a feasible and desirable strategy for medical strategy and showed great promise in the clinical therapy of asthma.

Chalcone-derivative L6H21 attenuates the OVA-induced asthma by targeting MD2

Asthma represents a significant global challenge that affects individuals across all age groups and imposes substantial social and economic burden. Due to heterogeneity of the disease, not all patients obtain benefit with current treatments. The objective of this study was to explore the impact of MD2 on the progression of asthma using L6H21, a novel MD2 inhibitor, to identify potential targets and drug candidates for asthma treatment. To establish an asthma-related murine model and evaluate the effects of L6H21, ovalbumin (OVA) was used to sensitize and challenge mice. Pathological changes were examined with various staining techniques, such as H&E staining, glycogen staining, and Masson staining. Inflammatory cell infiltration and excessive cytokine secretion were evaluated by analyzing BALF cell count, RT-PCR, and ELISA. The TLR4/MD2 complex formation, as well as the activation of the MAPK and NF-кB pathways, was examined using western blot and co-IP. Treatment with L6H21 demonstrated alleviation of increased airway resistance, lung tissue injury, inflammatory cell infiltration and excessive cytokine secretion triggered by OVA. In addition, it also ameliorated mucus production and collagen deposition. In the L6H21 treatment group, inhibition of MAPK and NF-кB activation was observed, along with the disruption of TLR4/MD2 complex formation, in contrast to the model group. Thus, L6H21 effectively reduced the formation of the MD2 and TLR4 complex induced by OVA in a dose-dependent manner. This reduction resulted in the attenuation of MAPKs/NF-κB activation, enhanced suppression of inflammatory factor secretion, reduced excessive recruitment of inflammatory cells, and ultimately mitigated airway damage. MD2 emerges as a crucial target for asthma treatment, and L6H21, as an MD2 inhibitor, shows promise as a potential drug candidate for the treatment of asthma.

Effect of Buteyko breathing technique on clinical and functional parameters in adult patients with asthma: a randomized, controlled study

BACKGROUND

The established therapy of asthma might be supported by additional non-pharmaceutical measures, such as the Buteyko breathing technique (BBT); however, the available data are mixed. To clarify the effects of BBT in patients with asthma, we investigated whether it led to clinical improvements with correlation to functional parameters.

METHODS

Using a randomized, controlled design, we studied two groups (n = 30 each) of patients with asthma under either BBT or usual therapy (UT) w/o BBT over a period of 3 months. The primary outcome comprised the voluntary control pause (CP) after 3 months, secondary outcomes an additional breathhold parameter, forced expiratory volume in 1 s (FEV1), capnovolumetry, exhaled nitric oxide (FeNO), Asthma Control Questionnaire (ACQ) and Nijmegen Questionnaire (NQ), and the use of medication (β2-agonists; inhaled corticosteroids, ICS).

RESULTS

CP showed significant time-by-group interaction [F(1,58.09) = 28.70, p < 0.001] as well as main effects for study group [F(1,58.27) = 5.91, p = 0.018] and time [F(1,58.36) = 17.67, p < 0.001]. ACQ and NQ scores were significantly (p < 0.05 each) improved with BBT. This was associated with reductions in the use of β2-agonists and ICS (p < 0.05 each) by about 20% each. None of these effects occurred in the UT group. While FEV1 and the slopes of the capnovolumetric expiratory phases 2 and 3 did not significantly change, the capnovolumetric threshold volume at tidal breathing increased (p < 0.05) with BBT by about 10 mL or 10%, compared to baseline, suggesting a larger volume of the central airways. No significant changes were seen for FeNO.

CONCLUSIONS

BBT was clinically effective, as indicated by the fact that the improvement in symptom scores and the small increase in bronchial volume occurred despite the significant reduction of respiratory pharmacotherapy. As the self-controlled Buteyko breathing therapy was well-accepted by the participants, it could be considered as supporting tool in asthma therapy being worth of wider attention in clinical practice. Trial registration Retrospectively registered on 10 March 2017 at ClinicalTrials.gov (NCT03098849).

Effects of total alkaloids from Alstonia scholaris (L.) R. Br. on ovalbumin-induced asthma mice

ETHNOPHARMACOLOGICAL RELEVANCE

More than 300 million people worldwide suffer from asthma, a chronic respiratory inflammatory disease. Total alkaloids (TA) were extracted from the ethnic medicinal plant Alstonia solaris (L.) R.Br., which is used to treat respiratory diseases. They may be effective drugs for treating asthma, but research is still needed to determine their effectiveness and mechanism in treating asthma.

AIM OF THE STUDY

To further understand TA's role in the treatment of asthma and to support the phase II trial of the drug.

MATERIALS AND METHODS

In this study, we investigated the effects of TA in a mouse asthma model produced by Ovalbumin (OVA). H&E and PAS staining were used to observe the histopathological features of lung. airway hyperresponsiveness (AHR) was detected by ventilator; The expression of interleukin (IL)-33, suppression of tumorigenicity 2 (ST2) and E-cadherin in the lungs was evaluated by IHC. The concentrations of Mucin5AC (MUC5AC), eotaxin, IL-4, IL-5, IL-9, IL-13, interferon (IFN)-γ, IL-6, IL-8, IL-17A, IL-33, IL-25, thymic stromal lymphopoietin (TSLP), monocyte chemoattractant protein 1 (MCP-1), leukotriene (LT) B4, LTC4, LTD4, LTE4 in bronchoalveolar lavage fluid (BALF) and total IgE (tIgE), OVA-Specific IgE (OVA-IgE) in serum were measured by ELISA. ILC2s and eosinophils were detected in lung tissue by flow cytometry. The gene expression levels of IL-33 and ST2 were detected by RT-qPCR.

RESULTS

Administration of TA reduced pulmonary inflammatory symptoms, MUC5AC production in the BALF, and AHR. At the same time, TA inhibited eotaxin production and eosinophil recruitment. Moreover, TA significantly decreased Th2 and Th17 cytokines and increased Th1 cytokines, contributing to restore the balance between Th1 and Th2 and Th17 cytokines. TA may reduce ILC2s numbers by inhibiting IL-33, IL-25, and TSLP levels in BALF and IL-33/ST2 signaling in lung tissue. Finally, TA decreased tIgE, OVA-IgE, and MCP-1 levels and subsequently inhibited mast cell activation and leukotriene release.

CONCLUSIONS

These findings imply that TA may be an effective immunoregulatory medication for the management and prevention of asthma.

Protective effects of Angelica decursiva Franchet & Savatier on allergic responses through enhancement of Nrf2 and suppression of NF-kB/MMP-9 in ovalbumin-exposed mice

ETHNOPHARMACOLOGICAL RELEVANCE

Angelica decursiva Franchet & Savatier is a traditional medicinal plant used to treat asthma, cough, headache, pyrexia and thick phlegm in China, Japan and Korea. A. decursiva contains many types of coumarins, which can exert several pharmacological activities including anti-inflammatory and antioxidant properties for treating various diseases such as pneumonitis, atopic dermatitis, diabetes, and Alzheimer's disease.

AIM OF THE STUDY

In this study, we analyzed the components of A. decursiva ethanol extract (ADE) by high performance liquid chromatography (HPLC) and investigated the therapeutic effects of ADE against allergic asthma using lipopolysaccharide (LPS) stimulated RAW264.7 cells and an ovalbumin (OVA)-exposed allergic asthma model. To elucidate the mechanism of action of ADE, we examined the protein expression through network pharmacological analysis.

MATERIALS AND METHODS

To establish asthma model, the mice were sensitized on day 0 and 14 via intraperitoneal injection of OVA with aluminum hydroxide. The mice were inhaled with OVA using an ultrasonic nebulizer on day 21, 22 and 23. ADE (50 and 100 mg/kg) was administered to mice by oral gave form day 18-23. On day 24, airway hyperresponsiveness (AHR) was measured using flexivent. On day 25, the mice were sacrificed and collected bronchoalveolar lavage fluids (BALF), serum and lung tissue. In LPS-stimulated RAW264.7 cell, nitric oxide and cytokines were measured. Additionally, expression of nuclear factor erythroid-2-related factor (Nrf2) and suppression of nuclear factor (NF)-κB were detected using double-immunofluorescence.

RESULTS

We detected the five coumarin components which included nodakenin, umbelliferon, (-)-marmesin (=nodakenetin), bergapten, and decursin, in ADE by high performance liquid chromatography. Treatment with ADE decreased the production of nitric oxide, interleukin (IL)-6 and tumor necrosis factor (TNF)-α in LPS-stimulated RAW264.7 cells accompanied by the enhanced expression of nuclear factor erythroid-2-related factor (Nrf2) and suppression of nuclear factor (NF)-κB. In the asthma model, the administration of ADE reduced inflammatory cell count and airway hyperresponsiveness in OVA-exposed animals with decreased levels of IL-4, IL-13, and OVA-specific immunoglobulin E. These results were accompanied by the reduction of pulmonary inflammation and mucus secretion. Furthermore, ADE administration inhibited the expression of NF-κB and matrix metalloproteinase (MMP)-9 in OVA-exposed animals, which was consistent with the results of network pharmacological analysis.

CONCLUSION

This study demonstrated that ADE effectively attenuated allergic inflammation induced by OVA inhalation through the enhancement of Nrf2 expression and suppression of NF-κB expression. Therefore, ADE may be a potential therapeutic agent for controlling asthma.

Prenatal dietary exposure to mixtures of chemicals is associated with allergy or respiratory diseases in children in the ELFE nationwide cohort

INTRODUCTION

Prenatal exposure to environmental chemicals may be associated with allergies later in life. We aimed to examine the association between prenatal dietary exposure to mixtures of chemicals and allergic or respiratory diseases up to age 5.5 y.

METHODS

We included 11,638 mother-child pairs from the French "Étude Longitudinale Française depuis l'Enfance" (ELFE) cohort. Maternal dietary exposure during pregnancy to eight mixtures of chemicals was previously assessed. Allergic and respiratory diseases (eczema, food allergy, wheezing and asthma) were reported by parents between birth and age 5.5 years. Associations were evaluated with adjusted logistic regressions. Results are expressed as odds ratio (OR[95%CI]) for a variation of one SD increase in mixture pattern.

RESULTS

Maternal dietary exposure to a mixture composed mainly of trace elements, furans and polycyclic aromatic hydrocarbons (PAHs) was positively associated with the risk of eczema (1.10 [1.05; 1.15]), this association was consistent across sensitivity analyses. Dietary exposure to one mixture of pesticides was positively associated with the risk of food allergy (1.10 [1.02; 1.18]), whereas the exposure to another mixture of pesticides was positively but slightly related to the risk of wheezing (1.05 [1.01; 1.08]). This last association was not found in all sensitivity analyses. Dietary exposure to a mixture composed by perfluoroalkyl acids, PAHs and trace elements was negatively associated with the risk of asthma (0.89 [0.80; 0.99]), this association was consistent across sensitivity analyses, except the complete-case analysis.

CONCLUSION

Whereas few individual chemicals were related to the risk of allergic and respiratory diseases, some consistent associations were found between prenatal dietary exposure to some mixtures of chemicals and the risk of allergic or respiratory diseases. The positive association between trace elements, furans and PAHs and the risk of eczema, and that between pesticides mixtures and food allergy need to be confirmed in other studies. Conversely, the negative association between perfluoroalkyl acids, PAHs and trace elements and the risk of asthma need to be further explored.

VEGF and EGFR signaling pathways are involved in the baicalein attenuation of OVA-induced airway inflammation and airway remodeling in mice

BACKGROUND

Although Traditional Chinese Medicine (TCM) has been used for treating asthma for centuries, the understanding of its mechanism of action is still limited. Thus, the purpose of this study was to explore the possible therapeutic effects, and underlying mechanism of baicalein in the treatment of asthma.

METHODS

Freely availabled atabases (e.g. OMIM, TTD, Genecards, BATMAN-TCM, STITCH 5.0, SEA, SwissTargetPrediction) and software (e.g. Ligplot 2.2.5 and PyMoL) were used for disease drug target prediction and molecular docking by network pharmacology. The efficacy and mechanism of action of baicalein in the treatment of asthma were validated using an ovalbumin (OVA)-induced asthma mouse model and molecular biology techniques.

RESULTS

A total of 1655 asthma-related genes and 161 baicalein-related targets were identified from public databases. Utilizing common databases and software for network pharmacology and molecular docking analysis, seven potential target proteins for the therapeutic effects of baicalein on asthma were selected, including v-akt murine thymoma viral oncogene homolog 1 (AKT1), vascular endothelial growth factor A (VEGFA), epidermal growth factor receptor (EGFR), proto-oncogene tyrosine-protein kinase Src (SRC), mitogen-activated protein kinase 3 (MAPK3), matrix metallopeptidase 9 (MMP9), and MAPK1. In vivo, baicalein treatment via intraperitoneal injection at a dose of 50 mg/kg significantly reduced airway inflammation, collagen deposition, smooth muscle thickness, lung interleukin (IL)-4 and IL-13 levels, peripheral blood immunoglobulin (Ig)E levels, as well as the count and ratio of eosinophils in bronchoalveolar lavage fluid (BALF) in an OVA-induced asthma mouse model. Further validation by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blotting analysis revealed that the VEGF and EGFR signaling pathways involving VEGFA, MAPK1, MAPK3, and EGFR were inhibited by baicalein in the asthma mouse model.

CONCLUSION

Baicalein attenuates airway inflammation and airway remodeling through inhibition of VEGF and EGFR signaling pathways in an OVA-induced asthma mouse model. This will provide a new basis for the development of baicalein as a treatment for asthma and highlights the potential of network pharmacology and molecular docking in drug discovery and development.

Early life exposure to particulate matter and childhood asthma in Beijing, China: a case-control study

A case-control study was conducted to examine the association of particulate matter exposure during the pre-natal (the first, second, and third trimesters. and the whole pregnancy) and post-natal periods (the first year after birth) with childhood asthma in Beijing, China. Multivariable logistic regressions showed that childhood asthma was significantly associated with exposures to PM2.5 and PM10 during the entire pregnancy, with ORs of 1.28(95%CI:1.06-1.56) and 1.21(95%CI:1.02-1.42), respectively. The highest association with a 10 μg/m3 increase in PM2.5 and PM10 were both seen for the second trimester, with ORs of 1.17(95% CI: 1.05-1.30) and 1.14(95% CI: 1.04-1.24). Subgroup analyses suggested that significant and positive effects were subject to be observed in children with a family history of atopy. This study added evidence that exposures to PM2.5 and PM10 during pregnancy might increase the risk of childhood asthma in seriously polluted area, highlighting stronger associations in the second trimester.