Novel pharmacological strategies to treat cognitive dysfunction in chronic obstructive pulmonary disease

Correlation between frailty and reduction in cortical thickness in patients with chronic obstructive pulmonary disease

Physical inactivity and cognitive impairment in patients with chronic obstructive pulmonary disease (COPD) can lead to frailty and poor prognoses. However, little is known regarding the association between frailty and the human brain. We hypothesized that the brain structure could change according to frailty in patients with COPD and focused on cortical thickness. Cortical thickness measured by magnetic resonance imaging and frailty scores using the Kihon Checklist (KCL) were assessed in 40 patients with stable COPD and 20 healthy controls. Among the 34 regions assessed, multiple regions were thinner in patients with COPD than in healthy individuals (p < 0.05). We found significant negative correlations between the eight regions and the KCL scores only in patients with COPD. After adjusting for age and cognitive impairment, the association between the left and six right regions remained statistically significant. The correlation coefficient was the strongest in the bilateral superior frontal gyrus (left: ρ = - 0.5319, p = 0.0006) (right: ρ = - 0.5361, p = 0.0005). Interestingly, among the KCL scores, the daily activity domain showed the strongest correlation (sensitivity, 90%; specificity, 73%) with the bottom quartile of the reduction in the superior frontal gyrus. Frailty in patients with COPD is associated with a thickness reduction in the cortical regions, reflecting social vulnerability.

Association between urinary phthalate metabolites and chronic obstructive pulmonary disease incidence in US adults: results from NHANES 2007-2018

Despite associations between urinary phthalates and respiratory symptoms and disorders have been investigated, knowledge about their impact on COPD incidence remains limited. Using data of 8242 adults (aged 20-80 years) from the 2007-2018 National Health and Nutrition Examination Survey (NHANES), the association of mixed urinary phthalate metabolites with COPD incidence was evaluated. Among them, 789 were COPD patients, and the rest were non-COPD participants. In the single-pollutant models, a variety of phthalate metabolites were identified as independent positive factors for COPD incidence, including mono-(carboxynonyl) phthalate (MCNP), mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP), mono-n-butyl phthalate (MnBP), mono-(3-carboxylpropyl) phthalate (MCPP), mono-ethyl phthalate (MEP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), and mono-benzyl phthalate (MBzP). Multi-pollutant models, including weighted quantile sum (WQS) regression, quantile-based g computation (qgcomp), and Bayesian kernel machine regression (BKMR) approaches consistently revealed the positive association between phthalates co-exposure and COPD incidence, and MCPP was recognized as the dominant positive driver. The positive association was more evident in the youth group and the male group. The interactions between certain phthalate metabolites in COPD were also observed. Given the limitations of the cross-sectional design of NHANES study, well-designed longitudinal studies are needed to verify or disprove these findings.

Roles of Omega-3 Polyunsaturated Fatty Acids in Managing Cognitive Impairment in Chronic Obstructive Pulmonary Disease: A Review

Chronic obstructive pulmonary disease (COPD) contributes significantly to the death of people worldwide, especially the elderly. An essential feature of COPD is pulmonary inflammation, which results from long-term exposure to noxious substances from cigarette smoking and other environmental pollutants. Pulmonary inflammatory mediators spill over to the blood, leading to systemic inflammation, which is believed to play a significant role in the onset of a host of comorbidities associated with COPD. A substantial comorbidity of concern in COPD patients that is often overlooked in COPD management is cognitive impairment. The exact pathophysiology of cognitive impairment in COPD patients remains a mystery; however, hypoxia, oxidative stress, systemic inflammation, and cerebral manifestations of these conditions are believed to play crucial roles. Furthermore, the use of medications to treat cognitive impairment symptomatology in COPD patients has been reported to be associated with life-threatening adverse effects, hence the need for alternative medications with reduced side effects. In this Review, we aim to discuss the impact of cognitive impairment in COPD management and the potential mechanisms associated with increased risk of cognitive impairment in COPD patients. The promising roles of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) in improving cognitive deficits in COPD patients are also discussed. Interestingly, ω-3 PUFAs can potentially enhance the cognitive impairment symptomatology associated with COPD because they can modulate inflammatory processes, activate the antioxidant defence system, and promote amyloid-beta clearance from the brain. Thus, clinical studies are crucial to assess the efficacy of ω-3 PUFAs in managing cognitive impairment in COPD patients.

Assessing Lung Inflammation and Pathology in Preclinical Models of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is an incurable disease that is a major cause of mortality and morbidity worldwide. Cigarette smoking is a major cause of COPD and triggers progressive airflow limitation, chronic lung inflammation, and irreversible lung damage and decline in lung function. COPD patients often experience various extrapulmonary comorbid diseases, including cardiovascular disease, skeletal muscle wasting, lung cancer, and cognitive decline which markedly impact on disease morbidity, progression, and mortality. People with COPD are also susceptible to respiratory infections which cause exacerbations of the underlying disease (AECOPD). The mechanisms and mediators underlying COPD and its comorbidities are poorly understood and current COPD therapy is relatively ineffective. We and others have used animal modelling systems to explore the mechanisms underlying COPD, AECOPD, and comorbidities of COPD with the goal of identifying novel therapeutic targets. Here we provide a preclinical model and protocols to assess the cellular, molecular, and pathological consequences of cigarette smoke exposure and the development of comorbidities of COPD.