Phenotypic Variations of Mild-to-Moderate Obstructive Pulmonary Diseases According to Airway Inflammation and Clinical Features

Distinct inflammatory profiles in mustard lung: A study of sulfur mustard-exposed patients with serious pulmonary complications

Mustard Lung (ML) refers to respiratory complications caused by sulfur mustard (SM) exposure, a chemical warfare agent. This study explores the inflammatory profile of SM-exposed veterans with serious ML, aiming to distinguish it from other respiratory diseases. The aim is also to comprehend the role of inflammatory markers in disease severity. A study was conducted on 257 male SM-exposed veterans and 64 unexposed control subjects. Inflammatory markers in serum and sputum samples were measured using the ELISA technique. Clinical evaluations identified the SM-exposed group as the patients with serious problems. Statistical analyses were conducted to compare groups. SM-exposed veterans exhibited decreased serum levels of IL-1α, IL-8, IL-17, GM-CSF, and NO compared to controls, while other markers did not differ significantly. Intriguingly, inflammatory patterns in ML subgroups, including those resembling Bronchiolitis Obliterans (BO), Chronic Bronchitis (CB), and asthma, differed from the corresponding cases of these diseases as reported in prior literature. Additionally, certain factors demonstrated notable decreases in concentration in severe ML cases compared to controls. The study reveals substantial changes in inflammatory markers in ML patients, highlighting their distinctive profile compared to other respiratory conditions. Despite some similarities with asthma, BO, and CB, the ML shows discernible variations in the levels of most inflammatory markers. Furthermore, the severity of ML impacted the serum levels of specific factors. These findings support the notion of classifying ML as a separate pulmonary condition, distinct from CB, BO, and asthma, opening avenues for further research and tailored treatment strategies.

GATA1-activated lncRNA OIP5-AS1 and GAS5 promote pyroptosis to exacerbate asthma through regulating miR-136-5p/LIFR axis

Pyroptosis plays a pivotal role in airway epithelial inflammation during the progression of asthma. This study aimed to explore the influence and mechanisms of opa-interacting protein 5 antisense RNA1 (OIP5-AS1) and growth arrest-specific transcript 5 (GAS5) on pyroptosis in asthmatic models. Pyroptosis was induced in Dermatophagoides pteronyssinus 1 (Der p1)-exposed 16HBE cells and ovalbumin (OVA)-challenged rats. Subsequently, pyroptosis and its related molecular mechanisms were investigated. Our results indicated that GATA1, OIP5-AS1, GAS5, and LIFR were upregulated, while miR-136-5p was downregulated in the patients and experimental models of asthma. OIP5-AS1/GAS5 knockdown repressed NLRP3 inflammasome-mediated pyroptosis in 16HBE cells. Mechanistically, OIP5-AS1/GAS5 sponged miR-136-5p to enhance LIFR expression and subsequently activated NF-κB pathway. OIP5-AS1, GAS5, or LIFR-mediated induction of pyroptosis was abrogated by miR-136-5p mimics or NF-κB inhibitors (BAY11-7082). Finally, GATA1 transcriptionally activated OIP5-AS1/GAS5 to trigger pyroptosis, thereby driving asthma progression in vivo and in vitro. In conclusion, OIP5-AS1/GAS5 transcriptionally activated by GATA1 promoted NLRP3 inflammasome-mediated pyroptosis via the modulation of miR-136-5p/LIFR/NF-κB axis and consequently resulted in airway inflammation in asthma. Our results may provide novel therapeutic strategies for asthma.

The value of bronchodilator response in FEV1 and FeNO for differentiating between chronic respiratory diseases: an observational study

BACKGROUND

There is no uniform standard for a strongly positive bronchodilation test (BDT) result. In addition, the role of bronchodilator response in differentiating between asthma, chronic obstructive pulmonary disease (COPD), and asthma-COPD overlap (ACO) in patients with a positive BDT result is unclear. We explored a simplified standard of a strongly positive BDT result and whether bronchodilator response combined with fractional exhaled nitric oxide (FeNO) can differentiate between asthma, COPD, and ACO in patients with a positive BDT result.

METHODS

Three standards of a strongly positive BDT result, which were, respectively, defined as post-bronchodilator forced expiratory volume in 1-s responses (ΔFEV1) increasing by at least 400 mL + 15% (standard I), 400 mL (standard II), or 15% (standard III), were analyzed in asthma, COPD, and ACO patients with a positive BDT result. Receiver operating characteristic curves were used to determine the optimal values of ΔFEV1 and FeNO. Finally, the accuracy of prediction was verified by a validation study.

RESULTS

The rates of a strongly positive BDT result and the characteristics between standards I and II were consistent; however, those for standard III was different. ΔFEV1 ≥ 345 mL could predict ACO diagnosis in COPD patients with a positive BDT result (area under the curve [AUC]: 0.881; 95% confidence interval [CI] 0.83-0.94), with a sensitivity and specificity of 90.0% and 91.2%, respectively, in the validation study. When ΔFEV1 was < 315 mL combined with FeNO < 28.5 parts per billion, patients with a positive BDT result were more likely to have pure COPD (AUC: 0.774; 95% CI 0.72-0.83).

CONCLUSION

The simplified standard II can replace standard I. ΔFEV1 and FeNO are helpful in differentiating between asthma, COPD, and ACO in patients with a positive BDT result.