Chronic Obstructive Pulmonary Disease: The Present and Future

Cellular and Molecular Biology of Mitochondria in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a progressive respiratory disorder characterized by enduring airflow limitation and chronic inflammation. Growing evidence highlights mitochondrial dysfunction as a critical factor in COPD development and progression. This review explores the cellular and molecular biology of mitochondria in COPD, focusing on structural and functional changes, including alterations in mitochondrial shape, behavior, and respiratory chain complexes. We discuss the impact on cellular signaling pathways, apoptosis, and cellular aging. Therapeutic strategies targeting mitochondrial dysfunction, such as antioxidants and mitochondrial biogenesis inducers, are examined for their potential to manage COPD. Additionally, we consider the role of mitochondrial biomarkers in diagnosis, evaluating disease progression, and monitoring treatment efficacy. Understanding the interplay between mitochondrial biology and COPD is crucial for developing targeted therapies to slow disease progression and improve patient outcomes. Despite advances, further research is needed to fully elucidate mitochondrial dysfunction mechanisms, discover new biomarkers, and develop targeted therapies, aiming for comprehensive disease management that preserves lung function and enhances the quality of life for COPD patients.

Association of Prefrailty and Frailty With All-Cause Mortality, Acute Exacerbation, and Hospitalization in Patients With Chronic Obstructive Pulmonary Disease: A Meta-Analysis

OBJECTIVE

To evaluate the impact of prefrailty and frailty on all-cause mortality, acute exacerbation, and all-cause hospitalization in patients with chronic obstructive pulmonary disease (COPD).

DESIGN

Meta-analysis.

SETTING AND PARTICIPANTS

Two authors independently searched PubMed, Web of Science, and Embase databases until December 27, 2022，to identify studies that reported the predictive value of prefrailty and frailty in COPD patients.

MEASUREMENTS

All-cause mortality, acute exacerbation, and all-cause hospitalization.

RESULTS

Ten studies reporting on 11 articles enrolling 13,203 patients with COPD were included. The prevalence of frailty ranged from 6.0% to 51%. When compared with nonfrailty, the pooled adjusted hazard ratio (HR) of all-cause mortality was 1.48 (95% CI 0.92-2.40) for prefrailty and 2.64 (95% CI 1.74-4.02) for frailty, respectively. The pooled adjusted odds ratio (OR) of all-cause hospitalization was 1.35 (95% CI 1.05-1.74) for prefrailty and 1.65 (95% CI 1.05-2.61) for frailty. In addition, frailty significantly predicted all acute exacerbation (OR 2.20, 95% CI 1.26-3.81) but not moderate to severe acute exacerbation (OR 1.42, 95% CI 0.94-2.17) in patients with stable COPD. However, the pooled results of all-cause hospitalization were not reliable in leave-1-out sensitivity analyses.

CONCLUSIONS AND IMPLICATIONS

Frailty significantly predicts all-cause mortality in patients with COPD, even after adjustment for common confounding factors. Assessment of frail status in COPD patients may improve secondary prevention and allow early intervention. However, future studies are warranted to validate the impact of frailty defined by a standardized definition of frailty on acute exacerbation and all-cause hospitalization.

Biological and Genetic Mechanisms of COPD, Its Diagnosis, Treatment, and Relationship with Lung Cancer

Chronic obstructive pulmonary disease (COPD) is one of the most prevalent chronic adult diseases, with significant worldwide morbidity and mortality. Although long-term tobacco smoking is a critical risk factor for this global health problem, its molecular mechanisms remain unclear. Several phenomena are thought to be involved in the evolution of emphysema, including airway inflammation, proteinase/anti-proteinase imbalance, oxidative stress, and genetic/epigenetic modifications. Furthermore, COPD is one main risk for lung cancer (LC), the deadliest form of human tumor; formation and chronic inflammation accompanying COPD can be a potential driver of malignancy maturation (0.8-1.7% of COPD cases develop cancer/per year). Recently, the development of more research based on COPD and lung cancer molecular analysis has provided new light for understanding their pathogenesis, improving the diagnosis and treatments, and elucidating many connections between these diseases. Our review emphasizes the biological factors involved in COPD and lung cancer, the advances in their molecular mechanisms' research, and the state of the art of diagnosis and treatments. This work combines many biological and genetic elements into a single whole and strongly links COPD with lung tumor features.

Liposomes or Extracellular Vesicles: A Comprehensive Comparison of Both Lipid Bilayer Vesicles for Pulmonary Drug Delivery

The rapid and non-invasive pulmonary drug delivery (PDD) has attracted great attention compared to the other routes. However, nanoparticle platforms, like liposomes (LPs) and extracellular vesicles (EVs), require extensive reformulation to suit the requirements of PDD. LPs are artificial vesicles composed of lipid bilayers capable of encapsulating hydrophilic and hydrophobic substances, whereas EVs are natural vesicles secreted by cells. Additionally, novel LPs-EVs hybrid vesicles may confer the best of both. The preparation methods of EVs are distinguished from LPs since they rely mainly on extraction and purification, whereas the LPs are synthesized from their basic ingredients. Similarly, drug loading methods into/onto EVs are distinguished whereby they are cell- or non-cell-based, whereas LPs are loaded via passive or active approaches. This review discusses the progress in LPs and EVs as well as hybrid vesicles with a special focus on PDD. It also provides a perspective comparison between LPs and EVs from various aspects (composition, preparation/extraction, drug loading, and large-scale manufacturing) as well as the future prospects for inhaled therapeutics. In addition, it discusses the challenges that may be encountered in scaling up the production and presents our view regarding the clinical translation of the laboratory findings into commercial products.