Effects of ozone repeated short exposures on the airway/lung inflammation, airway hyperresponsiveness and mucus production in a mouse model of ovalbumin-induced asthma

Dimethyl fumarate alleviates allergic asthma by strengthening the Nrf2 signaling pathway in regulatory T cells

Allergic asthma is a widely prevalent inflammatory condition affecting people across the globe. T cells and their secretory cytokines are central to the pathogenesis of allergic asthma. Here, we have evaluated the anti-inflammatory impact of dimethyl fumarate (DMF) in allergic asthma with more focus on determining its effect on T cell responses in allergic asthma. By utilizing the ovalbumin (OVA)-induced allergic asthma model, we observed that DMF administration reduced the allergic asthma symptoms and IgE levels in the OVA-induced mice model. Histopathological analysis showed that DMF treatment in an OVA-induced animal model eased the inflammation in the nasal and bronchial tissues, with a particular decrease in the infiltration of immune cells. Additionally, RT-qPCR analysis exhibited that treatment of DMF in an OVA-induced model reduced the expression of inflammatory cytokine (IL4, IL13, and IL17) while augmenting anti-inflammatory IL10 and Foxp3 (forkhead box protein 3). Mechanistically, we found that DMF increased the expression of Foxp3 by exacerbating the expression of nuclear factor E2-related factor 2 (Nrf2), and the in-vitro activation of Foxp3+ Tregs leads to an escalated expression of Nrf2. Notably, CD4-specific Nrf2 deletion intensified the allergic asthma symptoms and reduced the in-vitro iTreg differentiation. Meanwhile, DMF failed to exert protective effects on OVA-induced allergic asthma in CD4-specific Nrf2 knock-out mice. Overall, our study illustrates that DMF enhances Nrf2 signaling in T cells to assist the differentiation of Tregs, which could improve the anti-inflammatory immune response in allergic asthma.

Immunometabolism in the pathogenesis of asthma

Bronchial asthma is a heterogeneous disease characterised by chronic airway inflammation. A variety of immune cells such as eosinophils, mast cells, T lymphocytes, neutrophils and airway epithelial cells are involved in the airway inflammation and airway hyperresponsiveness in asthma pathogenesis, resulting in extensive and variable reversible expiratory airflow limitation. However, the precise molecular mechanisms underlying the allergic immune responses, particularly immunometabolism, remains unclear. Studies have detected enhanced oxidative stress, and abnormal metabolic progresses of glycolysis, fatty acid and amino acid in various immune cells, inducing dysregulation of innate and adaptive immune responses in asthma pathogenesis. Immunometabolism mechanisms contain multiple signalling pathways, providing novel therapy targets for asthma. This review summarises the current knowledge on immunometabolism reprogramming in asthma pathogenesis, as well as potential therapy strategies.

Anti-inflammatory effects of reticuline on the JAK2/STAT3/SOCS3 and p38 MAPK/NF-κB signaling pathway in a mouse model of obesity-associated asthma

BACKGROUND

Asthma associated with obesity is a chronic disease characterized by earlier airway remodeling, severe wheezing, and increased insensitivity to hormone therapy. Reticuline, a bioactive compound of Magnoliae Flos, exerts anti-inflammatory activity and can inhibit neutrophil recruitment. Thus, this study investigated the role of reticuline in obesity-related asthma.

METHODS

The BALB/c mice fed a low-fat diet (LFD) and high-fat diet (HFD) were intranasally challenged with house dust mites (HDMs) or ovalbumin (OVA). Reticuline (0.25 mg/kg) was administrated into mice by intragastrical gavage. Airway hyper-responsiveness was examined after the final challenge. Body weight was measured, and bronchoalveolar lavage fluid (BALF) and lung tissues were collected. The number of inflammatory cells in BALF was estimated. Histological changes were assessed by performing hematoxylin-eosin staining, and production of proinflammatory cytokines and IgE was examined by ELISA kits. Related pathways were studied with western blotting.

RESULTS

Reticuline suppressed airway resistance and inflammatory infiltration in lung tissue and reduced inflammatory cell recruitment in BALF in obesity mice with asthma. Additionally, the levels of IL-17A, IL-1β, IL-5, macrophage inflammatory protein 2, and regulated on activation, normal T cell expressed and secreted in the lung were reduced by reticuline. Mechanistically, reticuline inactivated the JAK2/STAT3/SOCS3 and p38 MAPK/NF-κB signaling pathways in obesity-related asthma.

CONCLUSION

Reticuline alleviates airway inflammation in obesity-related asthma by inactivating the JAK2/STAT3/SOCS3 and p38 MAPK/NF-κB signaling pathways.

High temperature exacerbates ozone-induced airway inflammation: Implication of airway microbiota and metabolites

Short-term exposure to ozone (O3) has been associated with airway inflammation. Given that high temperature (HT) accelerates O3 production, it is of significance to determine whether co-exposure to HT exacerbates O3-induced airway inflammation. The aim of this study was to examine the possible promotive effect of HT on O3-induced airway inflammation and underlying mechanisms. Forty-eight C57BL/6 N male mice were randomly divided into four groups: filtered air (control), O3, HT, and HT + O3 (co-exposure) groups. Mice in control and O3 groups were exposed to filtered air or 1 ppm O3 at 24 °C, respectively, while mice in HT and co-exposure groups were exposed to filtered air or 1 ppm O3 at 36 °C, respectively. The exposure scenario for four groups was 4 h/d for 5 consecutive days. Bronchoalveolar lavage fluids (BALF) were collected 24 h after the last exposure and subjected to examinations of oxidative stress and inflammation biomarkers, 16S rRNA sequencing, and metabolic profiling. Lung tissues were processed for H&E histological staining. The results showed that O3 inhalation triggered oxidative stress and inflammation in the airways, which was worsen by co-exposure to HT. Further studies revealed that co-exposure to HT strengthened O3-induced decline in Firmicutes and Allobaculum in airways. Moreover, co-exposure to HT promoted O3-induced airway metabolic disorder. Spearman correlation analysis revealed correlations among microbiota dysbiosis, metabolic disorder, oxidative stress and inflammation induced by co-exposure to HT and O3. Taken together, HT exposure aggravates O3-induced airway oxidative stress and inflammation, possibly through modulation of microbiota and metabolism of the airways.

Estimation of health risk and economic loss attributable to PM2.5 and O3 pollution in Jilin Province, China

Ambient pollutants, particularly fine particulate matter (PM2.5) and ozone (O3), pose significant risks to both public health and economic development. In recent years, PM2.5 concentration in China has decreased significantly, whereas that of O3 has increased rapidly, leading to considerable health risks. In this study, a generalized additive model was employed to establish the relationship of PM2.5 and O3 exposure with non-accidental mortality across 17 districts and counties in Jilin Province, China, over 2015-2016. The health burden and economic losses attributable to PM2.5 and O3 were assessed using high-resolution satellite and population data. According to the results, per 10 µg/m3 increase in PM2.5 and O3 concentrations related to an overall relative risk (95% confidence interval) of 1.004 (1.001-1.007) and 1.009 (1.005-1.012), respectively. In general, the spatial distribution of mortality and economic losses was uneven. Throughout the study period, a total of 23,051.274 mortalities and 27,825.015 million Chinese Yuan (CNY) in economic losses were attributed to O3 exposure, which considerably surpassing the 5,450.716 mortalities and 6,553,780 million CNY in economic losses attributed to PM2.5 exposure. The O3-related health risks and economic losses increased by 3.75% and 9.3% from 2015 to 2016, while those linked to PM2.5 decreased by 23.33% and 18.7%. Sensitivity analysis results indicated that changes in pollutant concentrations were the major factors affecting mortality rather than baseline mortality and population.

Immunomodulatory effect of glabridin in ovalbumin induced allergic asthma and its comparison with methylprednisolone in a preclinical rodent model

Glabridin, a polyphenolic flavonoid derived from Glycyrrhiza glabra (licorice) roots, has shown anti-inflammatory and antioxidant properties. The current study sought to investigate glabridin's immunomodulatory effect in ovalbumin induced allergic asthma. Healthy male Wistar rats were divided into five groups. Group I served as a control group. Asthma was induced in groups II- IV. Groups III and IV were treated with glabridin (40 mg/kg) and methylprednisolone (15 mg/kg), respectively. Inflammatory cells counts were determined in blood and bronchoalveolar lavage fluid (BALF). Serum IgE levels and levels of catalase, superoxide dismutase and glutathione peroxidase in lung homogenate were measured. The levels of mRNA expression of pro-inflammatory, anti-inflammatory and oxidative stress markers were analysed. Delayed type hypersensitivity (DTH) and acute toxicity of glabridin were also checked. Glabridin significantly decreased inflammatory cells in the blood and BALF. It increased the concentration of antioxidant enzymes catalase, superoxide dismutase and glutathione peroxidase. Glabridin markedly decreased serum IgE levels and DTH when compared to asthmatic rats. It significantly alleviated the expression of TNF-α, IL-4, IL-5, CXCL1, iNOS, and NF-κB. Administering 10 times the therapeutic dose of glabridin did not show any signs of acute toxicity. Findings suggest that glabridin has the potential to ameliorate allergic asthma and its effects are comparable to those of methylprednisolone. The immunomodulatory effect of glabridin might be contributed by the suppression of pro-inflammatory cytokines, oxidative stress markers, IgE antibodies, and elevation of antioxidant enzymes, suggesting future study and clinical trials to propose it as a candidate to treat allergic asthma.

TMT-based quantitative proteomics revealed protective efficacy of Icariside II against airway inflammation and remodeling via inhibiting LAMP2, CTSD and CTSS expression in OVA-induced chronic asthma mice

BACKGROUND

Asthma is a chronic inflammatory disorder in airways with typical pathologic features of airflow limitation, airway inflammation and remodeling. Icariside II (IS), derived from herbal medicine Herba Epimedii, exerts an anti-inflammatory property. However, underlying mechanisms with specifically targeted molecular expression by IS in asthma have not been fully understood, and whether IS could inhibit remodeling and EMT still remains unclear.

PURPOSE

The study aimed to clarify therapeutic efficacy of IS for attenuating airway inflammation and remodeling in asthma, and illustrate IS-regulated specific pathway and target proteins through TMT-based quantitative proteomics.

STUDY DESIGN AND METHODS

Murine model of chronic asthma was constructed with ovalbumin (OVA) sensitization and then challenge for 8 weeks. Pulmonary function, leukocyte count in bronchoalveolar lavage fluid (BALF), lung histopathology, inflammatory and fibrotic cytokines, and markers of epithelial-mesenchymal transition (EMT) were evaluated. TMT-based quantitative proteomics were performed on lung tissues to explore IS-regulated proteins.

RESULTS

IS contributed to alleviative airway hyperresponsiveness (AHR) evidenced by declined R_L and increased Cdyn. After IS treatment, we observed a remarked down-regulation of leukocyte count, inflammatory cytokines in BALF, and peribronchial inflammation infiltration. Goblet cell hyperplasia, mucus secretion and peribronchial collagen deposition were attenuated, with the level of TGF-β and MMP-9 in BALF declined. Furthermore, IS induced a rise of Occludin and E-cadherin and a decline of N-cadherin and α-SMA in lung tissues. These results proved the protective property of IS against airway inflammation, remodeling and EMT. To further investigate underlying mechanisms of IS in asthma treatment, TMT-based quantitative proteomics were performed and 102 overlapped DEPs regulated by IS were identified. KEGG enrichment exhibited these DEPs were enriched in lysosome, phagosome and autophagy, in which LAMP2, CTSD and CTSS were common DEPs. WB, q-PCR and IHC results proofed expressional alteration of these proteins. Besides, IS could decrease Beclin-1 and LC3B expression with increasing p62 expression thus inhibiting autophagy.

CONCLUSIONS

The study demonstrated IS could ameliorate AHR, airway inflammation, remodeling and EMT in OVA-induced chronic asthma mice. Our research was the first to reveal that inhibition of LAMP2, CTSD and CTSS expression in autophagy contributed to the therapeutic efficacy of IS to asthma.

Alteration of glycosphingolipid metabolism by ozone is associated with exacerbation of allergic asthma characteristics in mice

Asthma is a common chronic respiratory disease exacerbated by multiple environmental factors. Acute ozone exposure has previously been implicated in airway inflammation, airway hyperreactivity, and other characteristics of asthma, which may be attributable to altered sphingolipid metabolism. This study tested the hypothesis that acute ozone exposure alters sphingolipid metabolism within the lung, which contributes to exacerbations in characteristics of asthma in allergen-sensitized mice. Adult male and female BALB/c mice were sensitized intranasally to house dust mite (HDM) allergen on days 1, 3, and 5 and challenged on days 12-14. Mice were exposed to ozone following each HDM challenge for 6 h/day. Bronchoalveolar lavage, lung lobes, and microdissected lung airways were collected for metabolomics analysis (N = 8/sex/group). Another subset of mice underwent methacholine challenge using a forced oscillation technique to measure airway resistance (N = 6/sex/group). Combined HDM and ozone exposure in male mice synergistically increased airway hyperreactivity that was not observed in females and was accompanied by increased airway inflammation and eosinophilia relative to control mice. Importantly, glycosphingolipids were significantly increased following combined HDM and ozone exposure relative to controls in both male and female airways, which was also associated with both airway resistance and eosinophilia. However, 15 glycosphingolipid species were increased in females compared with only 6 in males, which was concomitant with significant associations between glycosphingolipids and airway resistance that ranged from R2 = 0.33-0.51 for females and R2 = 0.20-0.34 in male mice. These observed sex differences demonstrate that glycosphingolipids potentially serve to mitigate exacerbations in characteristics of allergic asthma.

Evaluating the effects of vitamin D Level on airway obstruction in two asthma endotypes in humans and in two mouse models with different intake of vitamin D during early-life

Introduction

Asthma is primarily divided into two categories: type 2 (T2-high) and non-type 2 (T2-low). A relationship between asthma severity and vitamin D deficiency has been identified, but its impact on each asthma endotype remains unknown.

Methods

We clinically examined the influence of vitamin D on patients with T2-high (n = 60) or T2-low asthma (n = 36) compared with controls (n = 40). Serum 25(OH)D levels, inflammatory cytokines and spirometry were measured. Mouse models were then used to further analyze the effects of vitamin D on both asthmatic endotypes. BALB/c mice were fed with vitamin D-deficient (LVD), -sufficient (NVD), or -supplemented diets (HVD) throughout lactation and offspring followed the same diet after weaning. Offspring were sensitized/challenged with ovalbumin (OVA) to establish "T2-high" asthma or OVA combined with ozone exposure (OVA + ozone) to induce "T2-low" asthma. Spirometry and serum, bronchoalveolar lavage fluid (BALF), and lung tissues were analyzed.

Results

Serum 25(OH)D levels were decreased in asthmatic patients compared with controls. Patients with vitamin D deficiency (Lo) had varying degrees of elevation of the pro-inflammatory cytokines IL-5, IL-6, and IL-17A, decreased expression of the anti-inflammatory cytokine IL-10, and altered forced expiratory volume in the first second as a percentage of predicted value (FEV₁%pred) in both asthmatic endotypes. Vitamin D status had a stronger correlation with FEV₁%pred in T2-low asthma than T2-high asthma, and 25(OH)D level was only positively linked to maximal mid-expiratory flow as a percentage of predicted value (MMEF%pred) in the T2-low group. Inflammation, hyperresponsiveness, and airway resistance (R_L) was increased in both asthma models compared with controls while vitamin D deficiency further increased airway inflammation and airway obstruction. These findings were particularly prominent in T2-low asthma.

Discussion

The potential function and mechanisms of vitamin D and both asthma endotypes should be studied individually, and further analysis of the potential signaling pathways involved with vitamin D on T2-low asthma is warranted.

Louki Zupa decoction attenuates the airway inflammation in acute asthma mice induced by ovalbumin through IL-33/ST2-NF-κB/GSK3β/mTOR signalling pathway

CONTEXT

Asthma is a common respiratory system disease. Louki Zupa decoction (LKZP), a traditional Chinese medicine, presents a promising efficacy against lung diseases.

OBJECTIVE

To investigate the pathogenic mechanism of asthma and reveal the intervention mechanism of LKZP.

MATERIALS AND METHODS

Forty-eight female Balb/c mice were randomly divided into 6 groups: normal control group (NC), ovalbumin (OVA)/saline asthma model group, OVA/LL group, OVA/LM group, OVA/LH group and OVA/DEX group (n = 8 per group). The asthmatic mice were modelled through intraperitoneal injecting and neutralizing OVA. LKZP decoction was administrated by gavage at the challenge stage for seven consecutive days (2.1, 4.2 and 8.4 g/kg/day). We investigated the change in lung function, airway inflammation, mucus secretion and TH-1/TH-2-related cytokines. We further verify the activated status of the IL-33/ST2/NF-κB/GSK3β/mTOR signalling pathway.

RESULTS

LKZP was proved to improve asthmatic symptoms, as evidenced by the down-regulated airway resistance by 36%, 58% and 53% (p < 0.01, p < 0.001 vs. OVA/saline group), up-regulated lung compliance by 102%, 114% and 111%, decreased airway inflammation and mucus secretion by 33%, 40% and 33% (p < 0.001 vs. OVA/saline group). Moreover, the content of cytokines in BALF related to airway allergy (such as IgE) and T helper 1/T helper 2 cells (like IL-2, IL-4, IL-5, IL-13, TNF-α and IFN-γ), were also markedly reduced by 13-65% on LKZP intervention groups compared with model group. Mechanistic research revealed that the IL-33/ST2-NF-κB/GSK3β/mTOR signalling pathway was activated in the OVA/saline group and LKZP significantly down-regulated this pathway.

DISCUSSION AND CONCLUSION

LKZP improves lung function, airway inflammation, mucus secretion and correct immune imbalance by intervening with the IL-33/ST2-NF-κB/GSK3β/mTOR signalling pathway, presenting a promising therapeutic choice for asthma.

Adipose-derived mesenchymal stem cells suppress ozone-mediated airway inflammation in a mouse model of chronic obstructive pulmonary disease

OBJECTIVE AND DESIGN

Ozone exposure is an important risk factor for Chronic Obstructive Pulmonary Disease (COPD) which is a global public health concern. Until now, there is no effective approach to reverse airflow limitation and accelerated loss of lung function completely. Here, we delineate the efficacy of mouse allogeneic adipose-derived mesenchymal stem cells (mASCs) in the treatment of COPD mice by intratracheal and intravenous administration.

METHODS

In this study, we established ozone-exposed COPD model in mice and were administered intratracheally or intravenously with mASCs which were extracted, cultured, and identified in vitro.

RESULTS

We observed that exposure to ozone resulted in a marked lung neutrophilia with high levels of inflammatory cell counts, enhanced expression of cytokines IL-1β and TNF-α, reduced expression of IL-10, lung function and airspace enlargement. mASCs intratracheal administration rescured the lung neutrophilia, lung function and emphysema-like phenotype. Similar results were observed in mice with mASCs intravenous administration. But the altered levels of serum cytokines in mice with mASCs intratracheal administration appears more robust than those in mice with mASCs intravenous administration.

CONCLUSIONS

Collectively, these data indicate that intratracheal administration of mASCs appears more effective in treating ozone-induced COPD compared to intravenous administration of mASCs, although the two approaches can be comparable in safety. mASCs are expected to become a new potential intervention strategy for COPD.

Tracking the response to Pseudomonas aeruginosa infection in ozone-induced chronic obstructive pulmonary disease mouse models

Pseudomonas aeruginosa (P. aeruginosa) is commonly isolated from the sputum of COPD patients. However, the precise role of P. aeruginosa infection in the progression of COPD, especially its role in altering inflammation remains unclear. Here, we designed mice models of COPD infected with P. aeruginosa (PA) and observed dynamic changes of lung structure, lung inflammatory microenvironment, lung function. After infection, the level of mucus secretion peaked on day 3 and remained higher throughout the study period, and the airway remodeling and emphysema was starkly apparent on day 14 and 21. On day 3, interferon-γ and interleukin (IL)- 5 levels increased rapidly, accompanied by elevated T-bet mRNA expression and CD4⁺T-bet⁺ cells; at the late stage of infection (days 14 and 21), consistent with increased GATA3 mRNA expression and CD4⁺GATA3⁺ cells, IL-4 and IL-13 levels significantly increased; IL-17A level, Foxp3 mRNA expression, CD4⁺ROR-γt⁺ cells and CD4⁺FOXP3⁺ cells remained at higher levels throughout the course of the infection. Small-airway function showed a decline from day 3 to day 21; large airway function showed a decline on day 14 and 21. Overall, P. aeruginosa infection contributed to the progression of COPD. During the infection, an early Th1-related inflammation gradually shifted to a later Th2-related inflammation, and small-airway function decline occurred earlier than that of large-airway function. On the basis of infection control, the appropriate use of glucocorticoid might slow disease progression by mitigating the enhanced Th2-related inflammation, and small airways could be also an important treatment target in P. aeruginosa -infected COPD patients.

STAT3 and IL-6 Contribute to Corticosteroid Resistance in an OVA and Ozone-induced Asthma Model with Neutrophil Infiltration

Exposure to high levels of ozone contributes to insensitivity to glucocorticoids in asthma treatment, but the underlying mechanisms are not known. We built two asthma models: a "T2-high" asthma model was established by ovalbumin (OVA) sensitization/challenge and OVA sensitization/challenge combined with ozone exposure (OVA + ozone) was used to induce airway inflammation with increased numbers of neutrophils to simulate "T2-low" asthma. The expression of T-helper (Th)1/2/17-related cytokines was measured by cytokine antibody arrays. Bronchial provocation tests were carried out to evaluate the lung resistance of mice. Hematoxylin and eosin staining, periodic acid-Schiff staining, and immunohistochemical (IHC) analyses of alpha-smooth muscle actin were undertaken to observe morphology changes in lungs. The expression of glucocorticoid receptors (GRs) and phosphorylated-GR (p-GR) was measured by western blotting. Nr3c1 mRNA was quantified by RT-qPCR. Protein expression of proinflammatory cytokines, signal transducer and activator of transcription 3 (STAT3), suppressor of cytokine signaling 3 (SOCS3), and CXCL1 was measured through ELISAs, western blotting, or IHC analyses. Resected lung tissue from seven asthma patients and 10 healthy controls undergoing thoracotomy for pulmonary nodules was evaluated by IHC analyses and ELISAs. In both asthma models, mucus hypersecretion, as well as inflammation, hyperresponsiveness, and remodeling of the airways, was present compared with the control group, whereas the OVA + ozone group showed severe neutrophil infiltration. The expression of Th17-related cytokines (interleukin (IL)-6, IL-17A, IL-21), GR protein, and CXCL1 increased in the OVA + ozone group, whereas the expression of p-GR decreased. Dexamethasone (Dex) could not totally reverse the expression of p-GR and histone deacetylase-2 in the OVA + ozone group. STAT3 expression increased in the OVA + ozone group and could not be completely reversed by Dex, and nor could IL-6 expression. A positive correlation between IL-6 or IL-17A and STAT3 and negative correlation between SOCS3 and STAT3 were shown, suggesting that the IL-6/STAT3 pathway may be involved in OVA + ozone-induced corticosteroid-resistant airway inflammation. In clinical samples, IL-17A expression in lung tissue was positively correlated with percent STAT3-positive area and negatively correlated with SOCS3 expression. The IL-6/STAT3 pathway may contribute to corticosteroid insensitivity in OVA + ozone-induced neutrophilic airway inflammation through regulation of Th17 cells and could provide new targets for individual treatment of corticosteroid resistance in asthma.

Cycloastragenol alleviates airway inflammation in asthmatic mice by inhibiting autophagy

Cycloastragenol (CAG), a secondary metabolite from the roots of Astragalus zahlbruckneri, has been reported to exert anti-inflammatory effects in heart, skin and liver diseases. However, its role in asthma remains unclear. The present study aimed to investigate the effect of CAG on airway inflammation in an ovalbumin (OVA)-induced mouse asthma model. The current study evaluated the lung function and levels of inflammation and autophagy via measurement of airway hyperresponsiveness (AHR), lung histology examination, inflammatory cytokine measurement and western blotting, amongst other techniques. The results demonstrated that CAG attenuated OVA-induced AHR in vivo. In addition, the total number of leukocytes and eosinophils, as well as the secretion of inflammatory cytokines, including interleukin (IL)-5, IL-13 and immunoglobulin E were diminished in bronchoalveolar lavage fluid of the OVA-induced murine asthma model. Histological analysis revealed that CAG suppressed inflammatory cell infiltration and goblet cell secretion. Notably, based on molecular docking simulation, CAG was demonstrated to bind to the active site of autophagy-related gene 4-microtubule-associated proteins light chain 3 complex, which explains the reduced autophagic flux in asthma caused by CAG. The expression levels of proteins associated with autophagy pathways were inhibited following treatment with CAG. Taken together, the results of the present study suggest that CAG exerts an anti-inflammatory effect in asthma, and its role may be associated with the inhibition of autophagy in lung cells.

Is small airway dysfunction an abnormal phenomenon for patients with normal forced expiratory volume in 1 second and the ratio of forced expiratory volume in 1 second to forced vital capacity?

BACKGROUND

The clinical significance of small airway dysfunction (SAD) determined with spirometry in patients with normal forced expiratory volume in 1 second (FEV1) and the ratio of FEV1 to forced vital capacity (FVC) is controversial.

OBJECTIVE

To determine whether SAD presents histologic abnormalities in the setting of normal computed tomography (CT) imaging and FEV1 and FEV1/FVC.

METHODS

A cross-sectional study was performed in 64 patients undergoing thoracotomy for pulmonary nodules. Thoracic high-resolution CT (HRCT), bronchodilation test, and fractional exhaled nitric oxide (FENO) and its alveolar component (nitric oxide alveolar concentration [CANO]) were obtained before surgery. Lung pathology and levels of cytokines in lung tissue were measured. The patients were divided into SAD and small airway normal function groups according to forced expiratory flow at 75% and 50% of the FVC (maximal expiratory flow [MEF] 25, MEF50) and maximum midexpiratory flow.

RESULTS

The MEF50, MEF25, and maximum midexpiratory flow were strongly negatively correlated with CANO (r, -0.42, -0.42, -0.40, respectively; P ≤ .001 for all). The MEFs were mildly negatively correlated with interleukin (IL)-6 and macrophages in lung tissue (r < -0.25, P < .001 for all). The CANO (P < .001), airspace size (mean linear intercept) (P = .02), macrophages (P = .003), IL-6 (P = .003), and IL-8 (P = .008) in lung tissue were higher in patients with SAD (n = 35) than those with small airway normal function (n = 29). A total of 8 patients (22.86%) with SAD and 2 (6.90%) without SAD had pneumatoceles (P = .10).

CONCLUSION

Patients with pulmonary nodules and SAD were more likely to have abnormal inflammation and emphysematous destruction than patients without SAD. Thus, SAD indicates histologic abnormalities in patients with normal CT imaging and FEV1 and FEV1/FVC.

Effect of Vitamin D Deficiency and Supplementation in Lactation and Early Life on Allergic Airway Inflammation and the Expression of Autophagy-Related Genes in an Ovalbumin Mouse Model

Background and Objective

Vitamin D is involved in various physiological and pathological processes, including inflammation and autophagy. We aimed to investigate the effects of dietary vitamin D deficiency or supplementation initiated in lactation and early life on inflammation and autophagy in an ovalbumin (OVA) mouse model.

Methods

Female BALB/c were fed with vitamin D-deficient, sufficient or supplemented diets throughout lactation and their offspring followed the same diet after weaning. Offspring were then sensitized and challenged with OVA, airway resistance (R_L) was measured, and their serum, bronchoalveolar lavage fluid (BALF), and lung tissue were collected. Alveolar macrophages (AMs) were isolated from lung tissue and cultured with different concentrations of 1,25(OH)₂D₃. The expressions of autophagy-related (ATG) proteins including light-chain 3 (LC3), Beclin-1, and ATG5, and NF-κB p65 in lung tissue and AMs were measured.

Results

OVA sensitization and challenge induced dramatic allergic airway inflammation and higher R_L in the vitamin D-deficient group compared with vitamin D-sufficient or the supplemented group. The expression of ATGs including LC3, Beclin-1, and ATG5, and NF-κB p65 in lung tissue in the vitamin D-deficient OVA-mediated group was increased compared with vitamin D-supplemented OVA-mediated group. There was correlation between the expression of LC3 mRNA and inflammatory cell numbers and cytokines in BALF. In vitro, 1,25(OH)₂D₃ also regulated the expression of LC3, Beclin-1, ATG5, and NF-κB p65 mRNA in AMs in a time- and dose-dependent manner.

Conclusion

Deficiency of vitamin D in early life may aggravate allergic airway inflammation, and maintaining sufficient vitamin D during early life is necessary for lung health. Vitamin D may modulate autophagy in lungs of OVA sensitized/challenged mice, thus playing a protective role in OVA-induced allergic airway inflammation.

Small-Airway Dysfunction is Involved in the Pathogenesis of Asthma: Evidence from Two Mouse Models

Background

There has been growing evidence of small-airway dysfunction in patients with asthma. Few studies have evaluated the mechanism of small-airway dysfunction in mouse models of asthma.

Purpose

We explored the correlation between small-airway spirometric variables and large-airway function or inflammation in different endotypes of asthma.

Methods

Ovalbumin (OVA) sensitization/challenge was used to produce a type 2 (T2)-high asthma model, and OVA combined with ozone exposure (OVA + ozone) was used for the T2-low asthma model with increased neutrophils. Spirometry, airway responsiveness, cytokine levels in bronchoalveolar lavage fluid (BALF), and pathological analyses of lung slices stained with hematoxylin-eosin, periodic acid–Schiff, and Masson’s trichrome stain were all determined. Muc5ac expression in lung tissue was evaluated by the reverse transcription-polymerase chain reaction (RT-PCR), and alpha-smooth muscle actin was measured by immunohistochemistry.

Results

Inflammatory cells infiltrated the lung tissue and inflammatory cytokines were increased in the BALF of both the OVA and OVA + ozone groups, compared with the control group. Peribronchial hypersecretion and collagen deposition were evident in the models. The OVA + ozone group showed greater neutrophilic infiltration and peribronchial smooth muscle proliferation than the OVA group. Large-airway obstruction, small-airway dysfunction, and airway hyperresponsiveness were confirmed in both models. Small-airway functional variables, such as MMEF (mean midexpiratory flow, average flow from 25 to 75% forced vital capacity [FVC]) and FEF50 (forced expiratory flow at 50% of FVC), were positively correlated with large-airway function and had a stronger negative correlation with airway inflammation, mucus secretion, and responsiveness than large-airway function.

Conclusion

Small-airway dysfunction was evident in the two endotypes of asthma and was correlated with severe airway inflammation, mucus hypersecretion, and airway hyperresponsiveness. The small airways may be an important target in asthma treatment, and further research in the role of small-airway variables in the pathogenesis of asthma is warranted.

Air Pollution and the Airways: Lessons from a Century of Human Urbanization

Since the industrial revolution, air pollution has become a major problem causing several health problems involving the airways as well as the cardiovascular, reproductive, or neurological system. According to the WHO, about 3.6 million deaths every year are related to inhalation of polluted air, specifically due to pulmonary diseases. Polluted air first encounters the airways, which are a major human defense mechanism to reduce the risk of this aggressor. Air pollution consists of a mixture of potentially harmful compounds such as particulate matter, ozone, carbon monoxide, volatile organic compounds, and heavy metals, each having its own effects on the human body. In the last decades, a lot of research investigating the underlying risks and effects of air pollution and/or its specific compounds on the airways, has been performed, involving both in vivo and in vitro experiments. The goal of this review is to give an overview of the recent data on the effects of air pollution on healthy and diseased airways or models of airway disease, such as asthma or chronic obstructive pulmonary disease. Therefore, we focused on studies involving pollution and airway symptoms and/or damage both in mice and humans.

Ozone inhalation induces exacerbation of eosinophilic airway inflammation and Th2-skew immune response in a rat model of AR

BACKGROUND

Ozone (O3) exposure elicits allergic rhinitis (AR) exacerbations by mechanisms that remain poorly understood. We used a rat model to investigate the effects of O3 on eosinophilic airway inflammation and Th2-related response.

METHODS

Sprague-Dawley (SD) rats were sensitized and challenged with ovalbumin (OVA) to make AR models. Three groups of AR rats were exposed respectively to 0.5, 1.0, 2.0 ppm of O3 for 2 h daily over 6 weeks consecutively and studied 24 h later. Normal rats exposed to O3 alone were used as controls. Nasal symptoms and OVA-specific immunoglobulin E (OVA-sIg E) in the serum were evaluated. Inflammatory cells in nasal lavage fluid (NLF) were classified and counted. Cytokines protein levels in NLF were assessed by ELISA. The pathological changes in the nasal mucosa were examined by histology.

RESULTS

The combination of allergen and repeated O3 exposure in rats induced a significant increase of the number of sneezes, nasal rubs, amount of nasal secretion and OVA-sIgE in the serum, accompanied by enhancement of eosinophils in NLF and nasal mucosa. The increase of interleukin-5 (IL-5), IL-13, Eotaxin and decrease of INF-γ protein levels in NLF were detected in AR rats after O3 inhalation. Hematoxylin and eosin staining showed disordered arrangement of the nasal mucosa epithelium and eosinophilic infiltration in a concentration-dependent manner.

CONCLUSIONS

O3 inhalation deteriorated symptoms in AR rats, and the possible mechanism is that ozone co-exposure could enhance the expression of Th2 cytokines, eosinophilic airway inflammation dose-dependently. The observation is helpful for us to understand the synergistic effect of O3 in the air pollution and allergen on aggravating allergic rhinitis.

TMT-based quantitative proteomics reveals suppression of SLC3A2 and ATP1A3 expression contributes to the inhibitory role of acupuncture on airway inflammation in an OVA-induced mouse asthma model

Asthma is a chronic airway inflammatory disease and acupuncture is frequently used in patients suffering from asthma in clinic. However, the regulatory mechanism of acupuncture treatment in asthma is not fully elucidated. We sought to investigate the effectiveness of acupuncture on asthma and the associated regulatory mechanism. An ovalbumin (OVA)-induced mouse asthma model was established and the effect of acupuncture on airway hyperresponsiveness (AHR), mucus hypersecretion and inflammation was assessed. Tandem mass tag (TMT)-based quantitative proteomics analysis of lung tissue and bioinformatics analysis were performed. Our results revealed that the OVA-induced mouse asthma model was successfully established with the significantly elevated AHR to methacholine (Mch), and acupuncture was effective in attenuation of AHR to Mch, peribronchial and perivascular inflammation and mucus production. The inflammatory cells around the airways, mucous secretion as well as levels of IgE, CCL5, CCL11, IL-17A in bronchoalveolar lavage fluid (BALF) and IL-4, IL-5 and IL-13 levels in serum were siginificantly inhibited by acupuncture. TMT-based quantitative proteomics analysis found that a total of 6078 quantifiable proteins were identified, and 564 (334 up-regulated and 230 down regulated) differentially expressed proteins (DEPs) were identified in OVA-induced asthma model group (A) versus normal control group (NC). Acupuncture treatment resulted in 667 DEPs (416 up-regulated and 251 down regulated) compared with A group, and 86 overlapping DEPs were identified in NC, A and AA groups. Among the 86 overlapping DEPs, we identified 41 DEPs regulated by acupuncture. Based on the above data, we performed a systematic bioinformatics analysis of the 41 DEPs, and results showed that these 41 DEPs were predominantly related to 4 KEGG pathways including SNARE interactions in vesicular transport, ferroptosis, endocrine and other factor-regulated calcium reabsorption, and protein digestion and absorption. DEPs of SLC3A2 and ATP1A3 expression levels were verified by immumohistochemical staining. Mice in OVA-induced asthma model group had elevated SLC3A2 and ATP1A3 expression and acupuncture had the ability to downregulate SLC3A2 and ATP1A3 protein expression. Furthermore, acupuncture reduced the MDA level and increased the GSH and SOD levels in the lung tissue. Taken together, our data suggested that acupuncture was effective in treating asthma by attenuation of AHR, mucus secretion and airway inflammation, and the mechanism was associated with regulation of ferroptosis, SLC3A2 and ATP1A3 protein expression as well as oxidative stress. Results from our experiments revealed the anti-inflammatory effect of acupuncture in OVA-induced mouse asthma model, leading to a more effective approach to be chosen by patients in clinic.

Associations between Levels of Urinary Oxidative Stress of 8-OHdG and Risk of Atopic Diseases in Children

The oxidative stress biomarker of urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) was reported to be changed in patients with allergic diseases. Measurement of urinary oxidative products is noninvasive. However, correlations between the severity levels of atopic diseases and oxidative stress remain unclear. This study aimed to investigate the association among urinary 8-OHdG, atopic dermatitis (AD), and the phenotypes of atopic diseases in children. In a nested case-control study, participants of kindergarten children were enrolled from the Childhood Environment and Allergic Diseases Study (CEAS). Urinary analyses and urinary 8-OHdG were performed on samples from 200 children with AD as cases and 200 age- and sex-matched controls. Our study presents the following main findings: (1) The urinary 8-OHdG levels were significantly higher in cases than controls. Higher urinary 8-OHdG levels were associated with the risk of AD in a dose-response-manner; (2) Children's AD history was associated with higher risks of asthma, allergic rhinitis, and night pruritus; (3) For children with AD, urinary 8-OHdG levels of >75th percentile were associated with higher risk of asthma, compared with the reference group of 0-25th percentiles. In summary, this study provides better understanding of the underlying mechanisms of AD and urinary 8-OHdG by analyzing a large-scale sample survey in Taiwan.

Associations between Levels of Urinary Oxidative Stress of 8-OHdG and Risk of Atopic Diseases in Children

The oxidative stress biomarker of urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) was reported to be changed in patients with allergic diseases. Measurement of urinary oxidative products is noninvasive. However, correlations between the severity levels of atopic diseases and oxidative stress remain unclear. This study aimed to investigate the association among urinary 8-OHdG, atopic dermatitis (AD), and the phenotypes of atopic diseases in children. In a nested case-control study, participants of kindergarten children were enrolled from the Childhood Environment and Allergic Diseases Study (CEAS). Urinary analyses and urinary 8-OHdG were performed on samples from 200 children with AD as cases and 200 age- and sex-matched controls. Our study presents the following main findings: (1) The urinary 8-OHdG levels were significantly higher in cases than controls. Higher urinary 8-OHdG levels were associated with the risk of AD in a dose-response-manner; (2) Children's AD history was associated with higher risks of asthma, allergic rhinitis, and night pruritus; (3) For children with AD, urinary 8-OHdG levels of >75th percentile were associated with higher risk of asthma, compared with the reference group of 0-25th percentiles. In summary, this study provides better understanding of the underlying mechanisms of AD and urinary 8-OHdG by analyzing a large-scale sample survey in Taiwan.

Adenovirus vector-mediated YKL-40 shRNA attenuates eosinophil airway inflammation in a murine asthmatic model

Recent studies have revealed that YKL-40 is involved in the pathogenesis of asthma. However, its specific mechanism remains unclear. The present study aims to investigate the effect of adenovirus vector-mediated YKL-40 short hairpin RNA (shRNA) on regulation of airway inflammation in a murine asthmatic model. Mice were assessed for airway hyperresponsiveness (AHR), total leukocytes and the percentage of eosinophil cells in bronchoalveolar lavage fluid (BALF). YKL-40 mRNA and protein expression levels were detected using quantitative real-time PCR and western blot assays. Enzyme-linked immunosorbent assay (ELISA) was used to detect YKL-40 and eosinophil-related chemokine expression levels in BALF and serum. Lung histology analyses were performed to evaluate the degree of inflammatory cell infiltration around the airway and airway mucus secretion.YKL-40 shRNA significantly inhibited the YKL-40 gene expression in asthmatic mice. In addition, YKL-40 shRNA alleviated eosinophilic airway inflammation, AHR, airway mucus secretion and decreased the levels of YKL-40 in BALF and serum in a murine asthmatic model. The levels and mRNA expression of IL-5, IL-13 in asthmatic mice lung tissues, eotaxin, and GM-CSF in BALF and serum significantly decreased. Bone marrow signaling molecules including IL-5, eotaxin, and GM-CSF were correlated with decreased levels of YKL-40. The study reveals that YKL-40 could be involved in asthma inflammation by altering bone marrow signaling molecules. YKL-40 gene RNA interference could provide new therapeutic strategies for asthma.

Oxidative Stress in Ozone-Induced Chronic Lung Inflammation and Emphysema: A Facet of Chronic Obstructive Pulmonary Disease

Oxidative stress plays an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD) caused by cigarette smoke and characterized by chronic inflammation, alveolar destruction (emphysema) and bronchiolar obstruction. Ozone is a gaseous constituent of urban air pollution resulting from photochemical interaction of air pollutants such as nitrogen oxide and organic compounds. While acute exposure to ozone induces airway hyperreactivity and neutrophilic inflammation, chronic ozone exposure in mice causes activation of oxidative pathways resulting in cell death and a chronic bronchial inflammation with emphysema, mimicking cigarette smoke-induced COPD. Therefore, the chronic exposure to ozone has become a model for studying COPD. We review recent data on mechanisms of ozone induced lung disease focusing on pathways causing chronic respiratory epithelial cell injury, cell death, alveolar destruction, and tissue remodeling associated with the development of chronic inflammation and AHR. The initial oxidant insult may result from direct effects on the integrity of membranes and organelles of exposed epithelial cells in the airways causing a stress response with the release of mitochondrial reactive oxygen species (ROS), DNA, and proteases. Mitochondrial ROS and mitochondrial DNA activate NLRP3 inflammasome and the DNA sensors cGAS and STING accelerating cell death pathways including caspases with inflammation enhancing alveolar septa destruction, remodeling, and fibrosis. Inhibitors of mitochondrial ROS, NLRP3 inflammasome, DNA sensor, cell death pathways, and IL-1 represent novel therapeutic targets for chronic airways diseases underlined by oxidative stress.

Short time exposure to ambient ozone and associated cardiovascular effects: A panel study of healthy young adults

The evidence that exposure to ambient ozone (O₃) causes acute cardiovascular effects appears inconsistent. A repeated-measure study with 61 healthy young volunteers was conducted in Xinxiang, Central China. Real-time concentrations of O₃ were monitored. Cardiovascular outcomes including blood pressure (BP), heart rate (HR), serum levels of high sensitivity C-reactive protein (hs-CRP), 8-hydroxy-2'-deoxyguanosine (8-OHdG), tissue-type plasminogen activator (t-PA), and platelet-monocyte aggregation (PMA) were repeated measured. Linear mixed-effect models were used to analyze the association of ambient O₃ with these cardiovascular outcomes. Additionally, the modifying effects of glutathione S-transferase mu 1 (GSTM1) and glutathione S-transferase theta 1 (GSTT1) polymorphisms were estimated to explore the potential mechanisms and role of the association between O₃ exposure and the above cardiovascular outcomes. A 10 μg/m³ increase in O₃ was associated with increases of 9.2 mmHg (95% confidence interval [CI]: 2.5, 15.9), 7.2 mmHg (95% CI: 0.8, 13.6), and 21.2 bpm (95% CI: 5.8, 36.6) in diastolic BP (DBP, lag1), mean arterial BP (MABP, lag1), and HR (lag01), respectively. Meanwhile, the serum concentrations of hs-CRP, 8-OHdG, and t-PA were all increased by O₃ exposure, but the PMA level was decreased. Stratification analyses showed that the estimated effects of O₃ on DBP, MABP, and HR in GSTM1-sufficient subjects were significantly higher than in GSTM1-null subjects. Moreover, GSTM1-null genotype enhanced O₃-induced increases, albeit insignificant, in levels of serum hs-CRP, 8-OHdG, and t-PA compared with GSTM1-sufficient genotype. Insignificant increases in hs-CRP and t-PA were also detected in GSTT1-null subjects. Taken together, our findings indicate that acute exposure to ambient O₃ induces autonomic alterations, systemic inflammation, oxidative stress, and fibrinolysis in healthy young subjects. GSTM1 genotype presents the trend of modifying O₃-induced cardiovascular effects.

Apolipoprotein E negatively regulates murine allergic airway inflammation via suppressing the activation of NLRP3 inflammasome and oxidative stress

Apolipoprotein E (ApoE) has been reported as a steroid unresponsive gene and functions as a negative regulator of airway hyperreactivity (AHR) and goblet cell hyperplasia in house dust mite (HDM)-challenged mice. However, the role of ApoE in Ovalbumin (OVA)-induced allergic airway inflammation disease and the underlying mechanism are still unknown. In the present study, murine allergic airway inflammation was induced by inhaled OVA for consecutive 7 days in wild type (WT) and ApoE^-/- mice. In the OVA-induced model, the ApoE level in the bronchoalveolar lavage fluid (BALF) and lung tissues was significantly higher than that of control mice. And ApoE deficiency aggravated airway inflammation including leukocytes infiltration, goblet cell hyperplasia and IgE production as compared to those of WT mice after OVA- challenged, suggesting ApoE servers as an endogenous negative regulator of airway inflammation. Furthermore, OVA challenge elevated the activation of NLRP3 inflammasome with higher protein expression of NLRP3, caspase1 and IL-1β, enhanced oxidative stress with higher expression of 8-OHdG, nitrotyrosine and SOD2, increased the expression of mitochondrial fusion/fission markers including Optic Atrophy 1 (OPA1), Mitofusion 2 (Mfn2), dynamin-related protein 1 (DRP1) and Fission 1 (Fis1). However, these OVA-induced changes were augmented in ApoE^-/- mice. Collectively, our results demonstrated that the OVA-induced airway inflammation was aggravated in ApoE^-/- mice, and suggested that the underlying mechanism may be associated with the augmented activation of NLRP3 inflammasome and oxidative stress in ApoE^-/- mice, therefore targeting ApoE pathway might be a novel therapy approach for allergic airway diseases such as asthma.

Transcriptional Effects of Ozone and Impact on Airway Inflammation

Epidemiological and challenge studies in healthy subjects and in individuals with asthma highlight the health impact of environmental ozone even at levels considered safe. Acute ozone exposure in man results in sputum neutrophilia in 30% of subjects particularly young children, females, and those with ongoing cardiopulmonary disease. This may be associated with systemic inflammation although not in all cases. Chronic exposure amplifies these effects and can result in the formation of asthma-like symptoms and immunopathology. Asthmatic patients who respond to ozone (responders) induce a greater number of genes in bronchoalveolar (BAL) macrophages than healthy responders with up-regulation of inflammatory and immune pathways under the control of cytokines and chemokines and the enhanced expression of remodeling and repair programmes including those associated with protease imbalances and cell-cell adhesion. These pathways are under the control of several key transcription regulatory factors including nuclear factor (NF)-κB, anti-oxidant factors such as nuclear factor (erythroid-derived 2)-like 2 NRF2, the p38 mitogen activated protein kinase (MAPK), and priming of the immune system by up-regulating toll-like receptor (TLR) expression. Murine and cellular models of acute and chronic ozone exposure recapitulate the inflammatory effects seen in humans and enable the elucidation of key transcriptional pathways. These studies emphasize the importance of distinct transcriptional networks in driving the detrimental effects of ozone. Studies indicate the critical role of mediators including IL-1, IL-17, and IL-33 in driving ozone effects on airway inflammation, remodeling and hyperresponsiveness. Transcription analysis and proof of mechanisms studies will enable the development of drugs to ameliorate the effects of ozone exposure in susceptible individuals.

Hydrogen sulfide exposure triggers chicken trachea inflammatory injury through oxidative stress-mediated FOS/IL8 signaling

Hydrogen sulfide (H₂S) is well known to cause irritation and damage to airway following inhalation, but the mechanism by which H₂S contributes to airway toxicity is unclear. In order to assess the respiratory toxicity of H₂S inhalation in chicken trachea, we investigated the change of oxidative stress parameters, tracheal tissue structure and transcriptome profiles of chicken trachea exposed to H₂S for 42 days. The results showed H₂S exposure induced oxidative stress and inflammation in trachea. The ultrastructural analysis revealed loss of cilia and accumulation of mucus in tracheal epithelium. Differentially expressed genes (DEGs) analysis indicated 454 genes were significantly changed, including 136 genes upregulated and 318 genes downregulated. Gene ontology and KEGG analysis showed many genes involved in response to oxidative stress, inflammatory and immune response, which might contribute to H₂S-induced tracheal inflammatory injury. Among those genes, N-acetyl-L-cysteine (NAC) treatment blocked the H₂S-triggered expression of FOS and IL8. Silencing FOS by siRNA inhibited H₂S-induced expression of IL8. Taken together, we concluded that H₂S induced oxidative stress leads to tracheal inflammation through FOS/IL8 signaling, leading to excessive mucus secretion and absence of cilia. These results provide new insights for unveiling the biological effects of H₂S in vivo and in vitro.

Synthesis and biological evaluation of Ginsenoside Compound K analogues as a novel class of anti-asthmatic agents

Ginsenoside Compound K (CK) showed potent activity against IgE for the treatment of asthma. A series of CK analogues were then synthesized by straightforward procedures. The in vivo anti-IgE activity evaluations using the OVA-induced asthmatic mouse model revealed preliminary SARs of the CK analogues, which showed that the sugar type, modifications on A-ring and the C20 side chain of CK all affected much on the activities. Primary SARs optimization led to the discovery of compounds T1, T2, T3, T8 and T12, which displayed superior or comparable anti-asthmatic effects (IgE value = 1237.11 ± 106.28, 975.82 ± 160.32, 1136.96 ± 121.85, 1191.08 ± 107.59 and 1258.27 ± 148.70 ng/mL, respectively) in comparison with CK (1501.85 ± 184.66 ng/mL). These potent compounds could serve as leads for further development.

The burden of ozone pollution on years of life lost from chronic obstructive pulmonary disease in a city of Yangtze River Delta, China

OBJECTIVE

Ambient ozone is one of the most important air pollutants with respect to its impacts on human health and its increasing concentrations globally. However, studies which explored the burden of ozone pollution on chronic obstructive pulmonary disease (COPD) and estimated the relevant economic loss were rare.

OBJECTIVE

We explored the relationships between ambient ozone exposure and years of life lost (YLL) from COPD mortality and estimated the relevant economic loss in Ningbo, in the Yangtze River Delta of China, 2011-2015.

METHODS

A time-series study was conducted to explore the effects of ozone on YLL from COPD. Seasonal stratified analyses were performed, and the effect modification of demographic factors was estimated. In addition, the related economic loss was calculated using the method of the value per statistical life year (VSLY).

RESULTS

Averaged daily mean maximum 8-h average ozone concentration was 40.90 ppb in Ningbo, China, 2011-2015. The effect of short term ambient ozone exposure on COPD YLL was more pronounced in the cool season than in the warm season, with 10 ppb increment of ozone corresponding to 7.09(95%CI: 3.41, 10.78) years increase in the cool season and 0.31 (95%CI: -2.15, 2.77) years change in the warm season. The effect was higher in the elderly than the young. Economic loss due to excess COPD YLL related to ozone exposure accounted for 7.30% of the total economic loss due to COPD YLL in Ningbo during the study period.

CONCLUSIONS

Our findings highlight that ozone exposure was related to tremendous disease burden of COPD in Ningbo, China. The effects were more pronounced in the cool season, and the elderly were more susceptible populations.