Identification of Asthma-COPD Overlap, Asthma, and Chronic Obstructive Pulmonary Disease Phenotypes in Patients with Airway Obstruction: Influence on Treatment Approach

TROP2 promotes PINK1-mediated mitophagy and apoptosis to accelerate the progression of senile chronic obstructive pulmonary disease by up-regulating DRP1 expression

Chronic obstructive pulmonary disease (COPD) is a chronic airway inflammatory disease characterised by irreversible airflow limitation. The elderly are a vulnerable population for developing COPD. With the growth of age, physiological degenerative changes occur in the thorax, bronchus, lung and vascular wall, which can lead to age-related physiological attenuation of lung function in the elderly, so the prevalence of COPD increases with age. Its pathogenesis has not yet been truly clarified. Mitophagy plays an important role in maintaining the stability of mitochondrial function and intracellular environment by scavenging damaged mitochondria. Currently, studies have shown that trophoblast antigen 2 (TROP2) expression is up-regulated in airway basal cells of patients with COPD, suggesting that TROP2 is involved in the progression of COPD. However, whether it is involved in disease progression by regulating mitochondrial function remains unclear. In this study, compared with non-smoking non-COPD patients, the expression of TROP2 in lung tissues of smoking non-COPD patients and patients with COPD increased, and TROP2 expression in patients with COPD was higher than that in smoking non-COPD patients. To further explore the role of TROP2, we stimulated BEAS-2B with cigarette smoke to construct an in vitro model. We found that TROP2 expression increased, whereas TROP2 silencing reversed the cigarette smoke extract-induced decrease in mitochondrial membrane potential, increased reactive oxygen species content, decreased adenosine triphosphate (ATP) production, increased inflammatory factor secretion and increased apoptosis. In addition, we searched online bioinformatics and screened the gene dynamin-related protein 1 (DRP1) related to mitophagy as the research object. Co-IP assay verified the binding relationship between DRP1 and TROP2. Further study found that TROP2 promoted mitophagy and apoptosis of BEAS-2B cells by up-regulating the expression of DRP1. In addition, PTEN-induced putative kinase 1 (PINK1) is a potential binding protein of DRP1, and DRP1 accelerated mitophagy and apoptosis of BEAS-2B cells by promoting the expression of PINK1. We established a COPD SD rat model by cigarette smoke exposure and LPS instillation and treated it by intraperitoneal injection of si-TROP2. The results showed that TROP2 silencing restored lung function and reduced the secretion of inflammatory factors in bronchoalveolar lavage fluid. In conclusion, TROP2 can be used as a new reference for COPD treatment.

Using inflammatory index to distinguish asthma, asthma-COPD overlap and COPD: A retrospective observational study

BACKGROUND

Although asthma and chronic obstructive pulmonary disease (COPD) are two well-defined and distinct diseases, some patients present combined clinical features of both asthma and COPD, particularly in smokers and the elderly, a condition termed as asthma-COPD overlap (ACO). However, the definition of ACO is yet to be established and clinical guidelines to identify and manage ACO remain controversial. Therefore, in this study, inflammatory biomarkers were established to distinguish asthma, ACO, and COPD, and their relationship with the severity of patients' symptoms and pulmonary function were explored.

MATERIALS AND METHODS

A total of 178 patients, diagnosed with asthma (n = 38), ACO (n = 44), and COPD (n = 96) between January 2021 to June 2022, were enrolled in this study. The patients' pulmonary function was examined and routine blood samples were taken for the analysis of inflammatory indexes. Logistic regression analysis was used to establish inflammatory biomarkers for distinguishing asthma, ACO, and COPD; linear regression analysis was used to analyze the relationship between inflammatory indexes and symptom severity and pulmonary function.

RESULT

The results showed that, compared with ACO, the higher the indexes of platelet, neutrophil-lymphocyte ratio (NLR) and eosinophil-basophil ratio (EBR), the more likely the possibility of asthma and COPD in patients, while the higher the eosinophils, the less likely the possibility of asthma and COPD. Hemoglobin and lymphocyte-monocyte ratio (LMR) were negatively correlated with the severity of patients' symptoms, while platelet-lymphocyte ratio (PLR) was negatively correlated with forced expiratory volume in the 1 s/forced vital capacity (FEV1/FVC) and FEV1 percent predicted (% pred), and EBR was positively correlated with FEV1% pred.

CONCLUSION

Inflammatory indexes are biomarkers for distinguishing asthma, ACO, and COPD, which are of clinical significance in therapeutic strategies and prognosis evaluation.

Effect of Respiration Training-Assisted Western Medicine Therapy on Activity Tolerance, Pulmonary Function, and Quality of Life of Chronic Obstructive Pulmonary Disease Patients in the Stable Phase

Objective

To explore the effect of respiration training-assisted western medicine therapy on activity tolerance, pulmonary function, and quality of life (QOL) of chronic obstructive pulmonary disease (COPD) patients in the stable phase.

Methods

The medical data of 90 COPD patients in the stable phase treated in the respiratory medicine of our hospital (November 2020-November 2021) were chosen for the retrospective analysis, and the patients were split into group A (n = 45, respiration training-assisted western medicine therapy) and group B (n = 45, western medicine therapy) according to the clinical reception order, so as to record and compare the activity tolerance, lung function, and QOL between the groups after intervention.

Results

Compared with group B after intervention, group A showed greatly longer mean 6-min walking distance, significantly lower St. George's Respiratory Questionnaire (SGRQ) score, significantly higher specific airway conductance (sGAW) and level values of various lung function indicators, and significantly lower level values of airway resistance (RAW) and specific airway resistance (sRAW) (p all<0.001); the total effective rate was significantly higher in group A (p < 0.05).

Conclusion

Respiration training-assisted western medicine therapy is a dependable way to improve the activity tolerance of COPD patients in the stable phase, and such strategy largely improves patients' lung function and QOL. Deeper studies will be helpful to establish a preferable solution for such patients.

Clinical and Inflammatory Features of Exacerbation-Prone Asthma: A Cross-Sectional Study Using Multidimensional Assessment

BACKGROUND

Reducing asthma exacerbations is a major target of current clinical guidelines, but identifying features of exacerbation-prone asthma (EPA) using multidimensional assessment (MDA) is lacking.

OBJECTIVE

To systemically explore the clinical and inflammatory features of adults with EPA in a Chinese population.

METHODS

We designed a cross-sectional study using the Severe Asthma Web-based Database from the Australasian Severe Asthma Network (ASAN). Eligible Chinese adults with asthma (n = 546) were assessed using MDA. We stratified patients based on exacerbation frequency: none, few (1 or 2), and exacerbation prone (≥3). Univariate and multivariable negative binomial regression analyses were performed to investigate features associated with the frequency of exacerbations.

RESULTS

Of 546 participants, 61.9% had no exacerbations (n = 338), 29.6% had few exacerbations (n = 162), and 8.4% were exacerbation prone (n = 46) within the preceding year. EPA patients were characterized by elevated blood and sputum eosinophils but less atopy, with more controller therapies but worse asthma control and quality of life (all p < 0.05). In multivariable models, blood and sputum eosinophils (adjusted rate ratio = 2.23, 95% confidence interval = [1.26, 3.84] and 1.67 [1.27, 2.21], respectively), FEV1 (0.90 [0.84, 0.96]), bronchodilator responsiveness (1.16 [1.05, 1.27]), COPD (2.22 [1.41, 3.51]), bronchiectasis (2.87 [1.69, 4.89]), anxiety (2.56 [1.10, 5.95]), and depression (1.94 [1.20, 3.13]) were found. Further, upper respiratory tract infection (1.83 [1.32, 2.54]) and food allergy (1.67 [1.23, 2.25]) were at high risk of asthma symptom triggers.

CONCLUSION

EPA is a clinically recognizable phenotype associated with several recognizable traits that could be addressed by targeted treatment.