Sputum and plasma endothelin-1 levels in exacerbations of chronic obstructive pulmonary disease

Changes in Retinal Nerve Fiber Layer Thickness in Patients With Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

PURPOSE

The purpose of this study is to evaluate the relationship between retinal nerve fiber layer (RNFL) thickness and the onset as well as progression of chronic obstructive pulmonary disease (COPD).

METHODS

Database searches were conducted in PubMed, Embase, Cochrane Library, Web of Science, CNKI, WanFang Data, VIP Database, and CBM, covering the period from each database's inception to March 2024.

RESULTS

This meta-analysis included 15 studies from 2016 to 2023, comprising a total of 1455 participants (801 in the COPD group and 654 in the health group). The results showed a significant reduction in RNFL thickness across all quadrants (average, inferior, nasal, superior, and temporal) in the COPD group compared to the health group (MD: -4.46; 95%CI: -7.77 to -1.14; p = 0.008; MD: -8.17; 95%CI: -11.36 to -4.99; p < 0.00001; MD: -4.69; 95%CI: -7.22 to -2.16; p = 0.0003; MD: -4.83; 95%CI: -8.45 to -1.21; p = 0.009; MD: -2.89; 95%CI: -5.35 to -0.43; p = 0.02). In the mild/moderate COPD group, only the inferior RNFL (MD: -2.32; 95%CI: -4.40 to -0.24; p = 0.03) showed a significant reduction. However, in the severe COPD group, all quadrants were significantly reduced (MD: -5.89; 95%CI: -7.40 to -4.38; p < 0.0001; MD: -6.74; 95%CI: -10.71 to -2.77; p = 0.0009; MD: -4.29; 95%CI: -5.95 to -2.64; p < 0.0001; MD: -2.34; 95%CI: -4.30 to -0.37; p = 0.02; MD: -4.84; 95%CI: -8.82 to -0.86; p = 0.02).

CONCLUSION

Based on current evidence, the average RNFL thickness and the thicknesses of various RNFL regions in COPD patients are significantly lower than those in healthy subjects, and these reductions are closely associated with disease severity. The inferior RNFL may be the first to show changes with the onset and progression of COPD.

WISP1 and Macrophage Migration Inhibitory Factor in Respiratory Inflammation: Novel Insights and Therapeutic Potentials for Asthma and COPD

Recent advancements highlight the intricate interplay between the extracellular matrix (ECM) and immune responses, notably in respiratory diseases such as asthma and Chronic Obstructive Pulmonary Disease (COPD). The ECM, a dynamic structural framework within tissues, orches-trates a plethora of cellular processes, including immune cell behavior and tissue repair mecha-nisms. WNT1-inducible-signaling pathway protein 1 (WISP1), a key ECM regulator, controls immune cell behavior, cytokine production, and tissue repair by modulating integrins, PI3K, Akt, β-catenin, and mTOR signaling pathways. WISP1 also induces macrophage migration inhibitory factor (MIF) expression via Src kinases and epidermal growth factor receptor (EGFR) activation. MIF, through its wide range of activities, enhances inflammation and tissue restructuring. Rec-ognized for its versatile roles in regulating the immune system, MIF interacts with multiple immune components, such as the NLRP3 inflammasome, thereby sustaining inflammatory pro-cesses. The WISP1-MIF axis potentially unveils complex molecular mechanisms governing im-mune responses and inflammation. Understanding the intricate roles of WISP1 and MIF in the pathogenesis of chronic respiratory diseases such as asthma and COPD could lead to the identi-fication of novel targets for therapeutic intervention to alleviate disease severity and enhance patient outcomes.

New markers in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD), a global healthcare and socioeconomic burden, is a multifaceted respiratory disorder that results in substantial decline in health status and life quality. Acute exacerbations of the disease contribute significantly to increased morbidity and mortality. Consequently, the identification of reliable and effective biomarkers for rapid diagnosis, prediction, and prognosis of exacerbations is imperative. In addition, biomarkers play a crucial role in monitoring responses to therapeutic interventions and exploring innovative treatment strategies. Although established markers such as CRP, fibrinogen and neutrophil count are routinely used, a universal marker is lacking. Fortunately, an increasing number of studies based on next generation analytics have explored potential biomarkers in COPD. Here we review those advances and the need for standardized validation studies in the appropriate clinical setting.

Inhalation of particulate matter containing environmentally persistent free radicals induces endothelial dysfunction mediated via AhR activation at the air-blood interface

Particulate matter (PM) containing environmentally persistent free radicals (EPFR) is formed by the incomplete combustion of organic wastes, resulting in the chemisorption of pollutants to the surface of PM containing redox-active transition metals. In prior studies in mice, EPFR inhalation impaired endothelium-dependent vasodilation. These findings were associated with aryl hydrocarbon receptor (AhR) activation in the alveolar type-II (AT-II) cells that form the air-blood interface in the lung. We thus hypothesized that AhR activation in AT-II cells promotes the systemic release of mediators that promote endothelium dysfunction peripheral to the lung. To test our hypothesis, we knocked down AhR in AT-II cells of male and female mice and exposed them to 280 µg/m3 EPFR lo (2.7e + 16 radicals/g) or EPFR (5.5e + 17 radicals/g) compared with filtered air for 4 h/day for 1 day or 5 days. AT-II-AhR activation-induced EPFR-mediated endothelial dysfunction, reducing endothelium-dependent vasorelaxation by 59%, and eNOS expression by 50%. It also increased endothelin-1 mRNA levels in the lungs and peptide levels in the plasma in a paracrine fashion, along with soluble vascular cell adhesion molecule-1 and iNOS mRNA expression, possibly via NF-kB activation. Finally, AhR-dependent increases in antioxidant response signaling, coupled to increased levels of 3-nitrotyrosine in the lungs of EPFR-exposed littermate control but not AT-II AhR KO mice suggested that ATII-specific AhR activation promotes oxidative and nitrative stress. Thus, AhR activation at the air-blood interface mediates endothelial dysfunction observed peripheral to the lung, potentially via release of systemic mediators.

The Potential Role of Angiotensin-Converting Enzyme Inhibitors and Beta-Blockers in Reducing Pneumonia Severity in Older Adults

Background Understanding the impact of pharmacological therapy on pneumonia severity is crucial for effective clinical management. The impact of angiotensin-converting enzyme inhibitors (ACEis) and beta-blockers (BBs) on pneumonia severity remains unknown, warranting further investigation. Methodology This retrospective study examined the hospital records of inpatients (≥75 years) admitted with community-acquired pneumonia in 2021. Pneumonia severity associated with the use of pre-established ACEi and BB therapy was documented using CURB-65 (confusion, uraemia, respiratory rate, blood pressure, age ≥65 years) and pneumonia severity index (PSI) scores. Descriptive statistics and multivariable linear regression were used to analyse differences across BB therapy, ACEi therapy, their combination, or neither (control group). Results A total of 803 patient records were examined, of whom 382 (47.6%) were male and 421 (52.4%) were female. Sample sizes for each group were as follows: control (n = 492), BB only (n = 185), ACEi only (n = 68), and BB + ACEi (n = 58). Distribution of aspiration pneumonia (AP) versus non-AP for each group, respectively, was control (21.1% vs. 78.9%), BB only (9.7% vs. 90.3%), ACEi only (7.3% vs. 92.7%), and ACEi + BB (12.1% vs. 87.9%). No significant differences in PSI and CURB-65 scores were found between intervention groups even after controlling for patient characteristics and irrespective of AP or non-AP aetiology. Patients with AP had significantly higher CURB-65 (p = 0.026) and PSI scores (p = 0.044) compared to those with non-AP. Conclusions Pre-prescribed ACEi or BB therapy did not appear to be associated with differences in pneumonia severity. There were no differences in pneumonia severity scores with ACEi and BB monotherapy or combined ACEi and BB therapy.

Efficacy and Safety of Bisoprolol in Patients with Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

Purpose

To evaluate the clinical efficacy and safety of bisoprolol in patients with chronic obstructive pulmonary disease (COPD).

Research Methods

This systematic review and meta-analysis was conducted following the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) statements. The primary outcome measures analyzed included: Pulmonary function(FEV1, FEV1%, FVC), 6-minute walking distance (6MWD), adverse events and inflammatory cytokines(IL-6, IL-8, CRP).

Results

Thirty-five studies were included with a total of 3269 study participants, including 1650 in the bisoprolol group and 1619 in the control group. The effect of bisoprolol on lung function in patients with COPD, FEV1, MD (0.46 [95% CI, 0.27 to 0.65], P=0.000), FEV1%, MD (-0.64 [95% CI, 0.42 to 0.86], P=0.000), FVC, MD (0.20 [95% CI, 0.05 to 0.34], P=0.008), the results all showed a statistically significant result. The effect of bisoprolol on 6MWD in COPD patients, MD (1.37 [95% CI, 1.08 to 1.66], P=0.000), which showed a statistically significant result. The occurrence of adverse events in COPD patients treated with bisoprolol, RR (0.83 [95% CI, 0.54 to 1.26], P=0.382), resulted in no statistical significance. The effect of bisoprolol on inflammatory cytokines in COPD patients, IL-6, MD (-1.16 [95% CI, -1.67 to -0.65], P=0.000), IL-8, MD (-0.94 [95% CI, -1.32 to -0.56], P=0.000), CRP, MD (-1.74 [95% CI, -2.40 to -1.09], P=0.000), the results were statistically significant. We performed a subgroup analysis of each outcome indicator according to whether the patients had heart failure or not, and the results showed that the therapeutic effect of bisoprolol on COPD did not change with the presence or absence of heart failure.

Conclusion

Bisoprolol is safe and effective in the treatment of COPD, improving lung function and exercise performance in patients with COPD, and also reducing inflammatory markers in patients with COPD, and this effect is independent of the presence or absence of heart failure.

Beta-blockers reduce severe exacerbation in patients with mild chronic obstructive pulmonary disease with atrial fibrillation: a population-based cohort study

BACKGROUND AND OBJECTIVE

Beta-blockers (BBs) decrease mortality and acute exacerbation (AE) rates in patients with chronic obstructive pulmonary disease (COPD) and cardiovascular disease; however, information on their effects in patients with COPD and atrial fibrillation (AF) is limited. We aimed to assess the AE risk in patients with different severities of COPD and AF receiving BBs compared with that in patients receiving calcium channel blockers (CCBs).

METHODS

This retrospective cohort study used data from the Taiwan National Health Insurance Database from 2009 to 2018. Outcomes included AE-related emergency room visits and hospitalisation. HRs and 95% CIs were estimated using the Cox proportional hazards model. COPD severity was classified as mild or severe based on exacerbation history. Sensitivity analyses included treatment and subgroup analyses, and competing risk adjustment.

RESULTS

After propensity score matching, 4486 pairs of BB and CCB users from 13 462 eligible patients were included. The exacerbation risk for BB users was lower (HR 0.80; 95% CI 0.72 to 0.89) than that of CCB users. After stratification, BB benefits persisted in the mild COPD group (HR 0.75; 95% CI 0.66 to 0.85), unlike the severe COPD group (HR 0.95; 95% CI 0.75 to 1.20). The results of the subgroup analysis showed consistent protective effects even in patients without heart failure or myocardial infarction (adjusted HR 0.82; 95% CI 0.71 to 0.94).

CONCLUSION

We found that BB use in patients with mild COPD and AF was associated with a lower exacerbation risk than CCB use, and that close monitoring of BB use in patients with severe COPD and AF is warranted.

Investigation of ocular microstructural changes according to disease severity in patients with chronic obstructive pulmonary disease

OBJECTIVE

To investigate retinal nerve fibre layer (RNFL) thickness and vascular density alterations in the retina and optic disc in patients with chronic obstructive pulmonary disease (COPD).

METHODS

A total of 66 COPD patients and 54 age- and sex-matched healthy individuals were enrolled in this prospective cross-sectional study. The COPD patients were divided into 3 subgroups (mild, moderate, and severe COPD) based on spirometric parameters as per the Global Initiative for Chronic Obstructive Lung Disease guideline. RNFL thickness, foveal avascular zone area, and vessel density in the superficial capillary plexus, deep capillary plexus, and radial peripapillary capillary plexus were measured by optical coherence angiography and compared among groups.

RESULTS

There was no significant difference between COPD patients and control individuals in terms of foveal avascular zone area or RNFL thickness (p = 0.891 and p = 0.896, respectively). Patients with severe COPD showed lower vessel density in the superficial capillary plexus compared with the other groups, but the difference was not significant (p > 0.05). In the deep capillary plexus, vessel density did not differ significantly among groups in the foveal region (p > 0.05) but was significantly lower in all parafoveal quadrants in the severe COPD group. Radial peripapillary capillary plexus vessel density also was lower in the severe COPD group, especially the peripapillary region (p = 0.044).

CONCLUSION

Although COPD is primarily a lung disease, the eye seems to be among the tissues affected in its natural course. The effects are more pronounced in patients with severe COPD and in the deep capillary plexus and radial peripapillary capillary plexus.

Alterations of Macular Structure in Non-Glaucomatous Subjects With Obstructive Pulmonary Function

Purpose

The purpose of this study was to identify possible associations between obstructive pulmonary function and macular structure parameters on optical coherence tomography (OCT) and angiography in subjects without glaucomatous optic neuropathy.

Methods

A total of 70 patients were prospectively enrolled from June to December 2021 as a part of All About Life Yongin-Pulmonary/Psychiatry, Rehabilitation, Eye (AALY PRE) cohort in Yongin Severance Hospital. Patients underwent intraocular pressure (IOP), visual acuity measurements, cirrus OCT, OCT angiography, and pulmonary function testing (PFT) on the same day. Subjects with glaucomatous optic nerve damage were excluded. Those whose first second of forced expiration (FEV1) to forced vital capacity (FVC) ratio was below 70% were diagnosed with obstructive pulmonary function. Vessel densities (VDs) of retinal superficial vascular plexus were compared.

Results

Patients with obstructive function (n = 30) were significantly older than those with normal pulmonary function (n = 40, P < 0.001). After adjusting for age, IOP, and average ganglion cell-inner plexiform layer (GCIPL) thickness, macular VD was significantly decreased in all sectors except for the nasal sector in subjects with obstructive pulmonary function in comparison to those with normal function (P = 0.006). Multivariate regression analysis demonstrated that macular VD was linearly associated with FEV1/FVC (β = 0.102, P = 0.031). In subjects with obstructive function, the severity of pulmonary obstruction, FEV1, was linearly associated with GCIPLT (β = 0.302, P = 0.017).

Conclusions

Obstructive pulmonary function is associated with reduced macular VD in subjects without glaucoma. Among subjects with obstructive pulmonary function, the severity of pulmonary obstruction is associated with GCIPL thickness in the macular region. Further studies are needed on the relationship between pulmonary function and macular disease.

Influence of dose and exposition time in the effectiveness of N-Acetyl-l-cysteine treatment in A549 human epithelial cells

N-Acetyl-l-cysteine (NAC) acts as a precursor of the tripeptide glutathione (GSH), one of the principal cell mechanisms for reactive oxygen species (ROS) detoxification. Chronic obstructive pulmonary disease (COPD) is associated with enhanced inflammatory response and oxidative stress and NAC has been used to suppress various pathogenic processes in this disease. Studies show that the effects of NAC are dose-dependent, and it appears that the efficient doses in vitro are usually higher than the achieved in vivo plasma concentrations. However, to date, the inconsistencies between the in vitro NAC antioxidant and anti-inflammatory in vitro effects, by reproducing the in vivo NAC plasma concentrations as well as high NAC concentrations. To do so, A549 were transfected with polyinosinic-polycytidylic acid (Poly (I:C)) and treated with NAC at different treatment periods. Oxidative stress, release of proinflammatory mediators and NFkB activation were analyzed. Results suggest that NAC at low doses in chronic administration has sustained antioxidant and anti-inflammatory effects, while acute treatment with high dose NAC exerts a strong antioxidant and anti-inflammatory response.

The alterations of retinal vasculature detected on optical coherence tomography angiography associated with chronic obstructive pulmonary disease

OBJECTIVES

This study aimed to evaluate the retinal vasculature of the macula and optic disc in patients with chronic obstructive pulmonary disease (COPD) by optical coherence tomography angiography (OCTA).

METHODS

The right eyes of 70 COPD patients and 71 healthy individuals were evaluated. These patients had moderate airflow limitation and mean PO2 of 60 mmHg, and their average age was less than 60 years. Superficial and deep capillary plexus vascular densities, foveal avascular zone (FAZ) width, and optic disc parameters were measured with OCTA. In addition, the correlation between the PO2 level in COPD patients and superficial, deep, and peripapillary vascular densities and FAZ was examined in the study.

RESULTS

The COPD group had a significant decrease in the vascular density in the superficial (fovea [p = 0.019]; parafovea [p = 0.013]; and perifovea [p = 0.001]) and deep capillary plexus (fovea [p = 0.028]; parafovea [p = 0.005]; and perifovea [p = 0.002]). Also, the enlargement of the FAZ (p = 0.002) and a decrease in the peripapillary vascular density (p = 0.006) were observed in the COPD group. There was a positive correlation between PO2 level and superficial, deep, and peripapillary vascular densities in COPD patients and a negative correlation with FAZ (r = 0.559-0.900).

CONCLUSION

Hypercapnia, respiratory acidosis, and chronic hypoxia associated with COPD may affect the macula and optic nerve, resulting in a serious decrease in vascular density, and OCTA can be a very important tool in the follow-up and treatment of these patients.

Retinal Vascular Changes in Patients with Chronic Obstructive Pulmonary Disease: An Optical Coherence Tomography Angiography Study

Objectives:

In the current study, we aimed to investigate retinal vascular density and blood flow changes in patients with chronic obstructive pulmonary disease (COPD) using optical coherence tomography angiography (OCTA) (AngioVue Avanti, Optovue).

Methods:

Thirty eyes of 30 patients with COPD and 30 eyes of 30 healthy controls were evaluated with OCTA. Foveal and parafoveal vessel density, inner retinal and choriocapillary flow area, and foveal avascular zone (FAZ) area were measured and compared between the groups.

Results:

No statistically significant differences were observed in the outer retinal flow area and choriocapillary flow area measurements between the groups (p=0.609 and p=0.162, respectively). There was no statistically significant difference in FAZ and FAZ perimeter values between the groups (p=0.725 and p=0.820, respectively). Vascular density measurements in the superficial foveal and parafoveal areas were not statistically significantly different between the groups (p>0.05, for all). Deep parafoveal vascular density values of the COPD group were statistically significantly lower than the control group in all investigated areas except the superior and inferior quadrants.

Conclusion:

The results of our study demonstrated for the first time that vascular density decreased in the parafoveal area due to COPD-related hypoxemia and endothelial dysfunction.

Effect of β-blockers on the risk of COPD exacerbations according to indication of use: the Rotterdam Study

Observational studies report a reduction of COPD exacerbations in patients treated with β-blockers. In contrast, the Beta-Blockers for the Prevention of Acute Exacerbations of Chronic Obstructive Pulmonary Disease (BLOCK COPD) randomised controlled trial which excluded COPD patients with cardiovascular conditions showed an increase in COPD exacerbations. It is unclear whether this discrepancy could be explained by underlying cardiovascular comorbidity. We examined whether the association between use of β-blockers and risk of COPD exacerbations differed between patients with and without a cardiovascular indication for β-blockers use.

Within the Rotterdam Study, we followed COPD subjects until the first COPD exacerbation, or end of follow-up. Cardiovascular indication for β-blockers use was defined as a history of hypertension, coronary heart disease, atrial fibrillation and/or heart failure at baseline. The association between β-blockers use and COPD exacerbations was assessed using Cox proportional hazards models adjusted for age, sex, smoking, incident cardiovascular disease (i.e. heart failure, hypertension, atrial fibrillation and/or coronary heart disease during follow-up), respiratory drugs and nitrates.

In total, 1312 COPD patients with a mean age of 69.7±9.2 years were included. In patients with a cardiovascular indication (n=755, mean age of 70.4±8.8 years), current use of cardioselective β-blockers was significantly associated with a reduced risk of COPD exacerbations (HR 0.69, 95% CI 0.57–0.85). In contrast, in subjects without a cardiovascular indication (n=557, mean age of 68.8±9.7 years), current use of cardioselective β-blockers was not associated with an altered risk of COPD exacerbations (HR 0.94, 95% CI 0.55–1.62).

Use of cardioselective β-blockers reduced the risk of exacerbations in COPD patients with concomitant cardiovascular disease. Therefore, the potential benefits of β-blockers might be confined to COPD patients with cardiovascular disease.

Use of cardioselective β-blockers reduces the risk of COPD exacerbations in patients with concomitant cardiovascular disease. The potential benefits of β-blockers might be restricted to COPD patients with cardiovascular disease.https://bit.ly/3bB1RGg

Endothelial Dysfunction during Acute Exacerbations of Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

Chronic obstructive pulmonary disease (COPD) is characterized by high cardiovascular risk, which is further amplified during acute COPD exacerbations (AECOPD). Endothelial dysfunction has been previously suggested as one of the potential pathogenetic mechanisms. In order to study the effects of AECOPD on endothelial function assessed by available functional methods, we performed a literature search involving Pubmed and Scopus databases. Eligible studies were those that included adult patients with COPD and evaluated endothelial damage via semi-invasive or noninvasive functional methods, during AECOPD and after recovery or in stable condition. Newcastle-Ottawa Scale was applied to evaluate the quality of retrieved studies. Endothelial function was significantly impaired during AECOPD compared to recovery/stable condition (SMD: -0.87, 95%CI [-1.19, -0.55]). Patients during AECOPD presented a significantly worse response in endothelium-dependent (flow-mediated dilatation WMD: -2.59, 95%CI [-3.75, -1.42]) and independent vasodilation (nitroglycerine-mediated dilatation WMD: -3.13, 95%CI [-5.18, -1.09]) compared to recovery. Sensitivity analyses confirmed the above results. In conclusion, endothelium-dependent and independent vasodilation is worse during AECOPD compared to the stable condition. Endothelial dysfunction could play a role in the high cardiovascular risk during AECOPD.

Angiotensin-converting enzyme 2 and COVID-19: patients, comorbidities, and therapies

On March 11, 2020, the World Health Organization declared coronavirus disease 2019 (COVID-19) a pandemic, and the reality of the situation has finally caught up to the widespread reach of the disease. The presentation of the disease is highly variable, ranging from asymptomatic carriers to critical COVID-19. The availability of angiotensin-converting enzyme 2 (ACE2) receptors may reportedly increase the susceptibility and/or disease progression of COVID-19. Comorbidities and risk factors have also been noted to increase COVID-19 susceptibility. In this paper, we hereby review the evidence pertaining to ACE2's relationship to common comorbidities, risk factors, and therapies associated with the susceptibility and severity of COVID-19. We also highlight gaps of knowledge that require further investigation. The primary comorbidities of respiratory disease, cardiovascular disease, renal disease, diabetes, obesity, and hypertension had strong evidence. The secondary risk factors of age, sex, and race/genetics had limited-to-moderate evidence. The tertiary factors of ACE inhibitors and angiotensin II receptor blockers had limited-to-moderate evidence. Ibuprofen and thiazolidinediones had limited evidence.

Association of β-blocker use with survival and pulmonary function in patients with chronic obstructive pulmonary and cardiovascular disease: a systematic review and meta-analysis

AIMS

The aim of this study was to clarify the effect of β-blockers (BBs) on respiratory function and survival in patients with chronic obstructive pulmonary disease with cardiovascular disease (CVD), as well as the difference between the effects of cardioselective and noncardioselective BBs.

METHODS AND RESULTS

We searched for relevant literature in four electronic databases, namely, PubMed, EMBASE, Cochrane Library, and Web of Science, and compared the differences in various survival indicators between patients with chronic obstructive pulmonary disease taking BBs and those not taking BBs. Forty-nine studies were included, with a total sample size of 670 594. Among these, 12 studies were randomized controlled trials (RCTs; seven crossover and five parallel RCTs) and 37 studies were observational (including four post hoc analyses of data from RCTs). The hazard ratios (HRs) of chronic obstructive pulmonary disease exacerbation between patients with chronic obstructive pulmonary disease who were not treated with BBs and those who were treated with BBs, cardioselective BBs, and noncardioselective BBs were 0.77 [95% confidence interval (CI) 0.67, 0.89], 0.72 [95% CI 0.56, 0.94], and 0.98 [95% CI 0.71, 1.34, respectively] (HRs <1 indicate favouring BB therapy). The HRs of all-cause mortality between patients with chronic obstructive pulmonary disease who were not treated with BBs and those who were treated with BBs, cardioselective BBs, and noncardioselective BBs were 0.70 [95% CI 0.59, 0.83], 0.60 [95% CI 0.48, 0.76], and 0.74 [95% CI 0.60, 0.90], respectively (HRs <1 indicate favouring BB therapy). Patients with Chronic obstructive pulmonary disease treated with cardioselective BBs showed no difference in ventilation effect after the use of an agonist, in comparison with placebo. The difference in mean change in forced expiratory volume in 1 s was 0.06 [95% CI -0.02, 0.14].

CONCLUSION

The use of BBs in patients with chronic obstructive pulmonary disease is not only safe but also reduces their all-cause and in-hospital mortality. Cardioselective BBs may even reduce chronic obstructive pulmonary disease exacerbations. In addition, cardioselective BBs do not affect the action of bronchodilators. Importantly, BBs reduce the heart rate acceleration caused by bronchodilators. BBs should be prescribed freely when indicated in patients with chronic obstructive pulmonary disease and heart disease.

Progress in the mechanism and targeted drug therapy for COPD

Chronic obstructive pulmonary disease (COPD) is emphysema and/or chronic bronchitis characterised by long-term breathing problems and poor airflow. The prevalence of COPD has increased over the last decade and the drugs most commonly used to treat it, such as glucocorticoids and bronchodilators, have significant therapeutic effects; however, they also cause side effects, including infection and immunosuppression. Here we reviewed the pathogenesis and progression of COPD and elaborated on the effects and mechanisms of newly developed molecular targeted COPD therapeutic drugs. Among these new drugs, we focussed on thioredoxin (Trx). Trx effectively prevents the progression of COPD by regulating redox status and protease/anti-protease balance, blocking the NF-κB and MAPK signalling pathways, suppressing the activation and migration of inflammatory cells and the production of cytokines, inhibiting the synthesis and the activation of adhesion factors and growth factors, and controlling the cAMP-PKA and PI3K/Akt signalling pathways. The mechanism by which Trx affects COPD is different from glucocorticoid-based mechanisms which regulate the inflammatory reaction in association with suppressing immune responses. In addition, Trx also improves the insensitivity of COPD to steroids by inhibiting the production and internalisation of macrophage migration inhibitory factor (MIF). Taken together, these findings suggest that Trx may be the ideal drug for treating COPD.

Physiological and pathological regulation of ACE2, the SARS-CoV-2 receptor

The renin-angiotensin system (RAS) is crucial for the physiology and pathology of all the organs. Angiotensin-converting enzyme 2 (ACE2) maintains the homeostasis of RAS as a negative regulator. Recently, ACE2 was identified as the receptor of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the coronavirus that is causing the pandemic of Coronavirus disease 2019 (COVID-19). Since SARS-CoV-2 must bind with ACE2 before entering the host cells in humans, the distribution and expression of ACE2 may be critical for the target organ of the SARS-CoV-2 infection. Moreover, accumulating evidence has demonstrated the implication of ACE2 in the pathological progression in tissue injury and several chronic diseases, ACE2 may also be essential in the progression and clinical outcomes of COVID-19. Therefore, we summarized the expression and activity of ACE2 in various physiological and pathological conditions, and discussed its potential implication in the susceptibility of SARS-CoV-2 infection and the progression and prognosis of COVID-19 patients in the current review.

Sputum and blood transcriptomics characterisation of the inhaled PDE4 inhibitor CHF6001 on top of triple therapy in patients with chronic bronchitis

Background

Although phosphodiesterase-4 (PDE4) inhibitors have been shown to reduce COPD exacerbation rate, their biological mechanism of action is not completely elucidated at the molecular level. We aimed to characterise the whole genome gene expression profile of the inhaled PDE4-inhibitor CHF6001 on top of triple therapy in sputum cells and whole blood of patients with COPD and chronic bronchitis.

Methods

Whole genome gene expression analysis was carried out by microarray in 54 patients before and after 32 days treatment with CHF6001 800 and 1600 μg and placebo twice daily (BID) in a randomised crossover study.

Results

CHF6001 had a strong effect in sputum, with 1471 and 2598 significantly differentially-expressed probe-sets relative to placebo (p-adjusted for False Discovery Rate < 0.05) with 800 and 1600 μg BID, respectively. Functional enrichment analysis showed significant modulation of key inflammatory pathways involved in cytokine activity, pathogen-associated-pattern-recognition activity, oxidative stress and vitamin D with associated inhibition of downstream inflammatory effectors. A large number of pro-inflammatory genes coding for cytokines and matrix-metalloproteinases were significantly differentially expressed for both doses; the majority (> 87%) were downregulated, including macrophage inflammatory protein-1-alpha and 1-beta, interleukin-27-beta, interleukin-12-beta, interleukin-32, tumour necrosis factor-alpha-induced-protein-8, ligand-superfamily-member-15, and matrix-metalloproteinases-7,12 and 14. The effect in blood was not significant.

Conclusions

Inhaled PDE4 inhibition by CHF6001 on top of triple therapy in patients with COPD and chronic bronchitis significantly modulated key inflammatory targets and pathways in the lung but not in blood. Mechanistically these findings support a targeted effect in the lung while minimising unwanted systemic class-effects.

Trial registration

ClinicalTrial.gov, EudraCT, 2015–005550-35. Registered 15 July 2016.

Beta-blockeRs tO patieNts with CHronIc Obstructive puLmonary diseasE (BRONCHIOLE) - Study protocol from a randomized controlled trial

BACKGROUND

Observational studies indicate that beta-blockers are associated with a reduced risk of exacerbation and mortality in patients with chronic obstructive pulmonary disease (COPD) even without overt cardiovascular disease, but data from randomized controlled trials (RCT) are lacking. The aim of this RCT is to investigate whether beta-blocker therapy in patients with COPD without diagnosed cardiovascular disease is associated with a decreased 1-year risk of the composite endpoint of death, exacerbations, or cardiovascular events.

METHODS

The Beta-blockeRs tO patieNts with CHronIc Obstructive puLmonary diseasE (BRONCHIOLE) study is an open-label, multicentre, prospective RCT. A total of 1700 patients with COPD will be randomly assigned to either standard COPD care and metoprolol at a target dose of 100 mg per day or to standard COPD care only. The primary endpoint is a composite of death, COPD exacerbations, and cardiovascular events. Major exclusion criteria are ischemic heart disease, left-sided heart failure, cerebrovascular disease, critical limb ischemia, and atrial fibrillation/flutter. Study visits are an inclusion visit, a metoprolol titration visit at 1 month, follow-up by telephone at 6 months, and a final study visit after 1 year. Outcome data are obtained from medical history and record review during study visits, as well as from national registries.

DISCUSSION

BRONCHIOLE is a pragmatic randomized trial addressing the potential of beta-blockers in patients with COPD. The trial is expected to provide relevant clinical data on the efficacy of this treatment on patient-related outcomes in patients with COPD.

TRIAL REGISTRATION

ClinicalTrials.gov, ID: NCT03566667. Registered on 25 June 2018.

The association of elevated circulating endocan levels with lung function decline in COPD patients

Background

Endocan is thought to be a novel inflammatory marker that is associated with a variety of inflammatory diseases. However, its role in the pathogenesis of COPD remains unclear. This study aims to explore the potential role of endocan in COPD.

Methods

In total, 27 healthy volunteers, 55 COPD patients and 36 acute exacerbation of chronic obstructive pulmonary disease (AECOPD) patients were included in the study. Basic demographic characteristics, clinical features and blood samples were collected. Magnetic luminex screening assays were used to detect the concentration of endocan, Fas and Fas ligand (Fas-L) in plasma. Differences between groups were compared using an Independent sample t-test, Welch’s t-test, chi-squared test and Wilcoxon rank sum test. The correlations of plasma endocan with lung function parameters, Fas and Fas-L were analyzed by Pearson’s partial correlation test (adjusted for age, gender, body mass index and smoking history) and multiple linear regression.

Results

Plasma endocan levels in COPD patients were significantly higher than those in healthy volunteers (509.7±18.25 pg/mL vs 434.8±18.98 pg/mL (P=0.0124)), and AECOPD patients had the highest levels of endocan (524.7±27.18 pg/mL). Correlation analysis showed that circulating endocan had a negative correlation to FEV₁/FVC, FEV₁/predictive and FVC (adjusted r=−0.213, P=0.03; adjusted r=−0.209, P=0.034; and adjusted r=−0.300, P=0.002, respectively), and had a positive correlation to Fas (adjusted r=0.280, P=0.004).

Conclusion

Our study shows that elevated circulating endocan levels are associated with reduced lung ventilation function in COPD and AECOPD patients. In addition, endocan may influence apoptosis in COPD, suggesting that endocan may play a role in COPD pathogenesis.

Looking into the eye of patients with chronic obstructive pulmonary disease: an opportunity for better microvascular profiling of these complex patients

Chronic obstructive pulmonary disease (COPD) is a complex disease with many patients suffering from cardiovascular comorbidity. However, cardiovascular diseases remain often undiagnosed in COPD. Assessment of the retinal microvasculature can provide value in cardiovascular profiling of these patients. Retinal microvascular assessment carried out via a noninvasive eye exam represents an easy to use tool when examining patients with COPD. The purpose of this review was to provide an overview of studies assessing structural and functional changes in the retinal microvasculature of patients with COPD. Findings demonstrated that structural and functional microvascular changes were more common and severe in COPD patients as compared to non-COPD controls, although few retinal investigations have been performed in patients with COPD. As cardiovascular comorbidities are highly prevalent in COPD, we advocate more research to investigate the value of an eye exam for microvascular phenotyping of COPD patients.

Choroid and Retinal Nerve Fiber Layer Thickness in Patients with Chronic Obstructive Pulmonary Disease Exacerbation

PURPOSE

We aimed at measuring the choroid and retinal nerve fiber layer thickness with optic coherence tomography (OCT) in patients diagnosed with chronic obstructive pulmonary disease (COPD).

METHODS

A total of 60 patients with COPD and 23 healthy controls were evaluated in the scope of this prospective, observational study. COPD patients were divided into two groups as those that were stable and those with an exacerbation based on the Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification. Subfoveal choroid thickness (SFCT) of the patients and the control group was compared by measuring the choroid thickness at points 1000 µm nasal and temporal to the fovea and the mean retinal nerve fiber layer (RNFL) thickness.

RESULTS

The subfoveal choroid thickness of the COPD patients in both the exacerbation and stable groups was found to be statistically significantly thinner than the control group (p=0.047 and p=0.046, resp.). No statistically significant difference was found between the subfoveal choroid thickness of the patients that were stable and those that had an exacerbation (p=0.813). No statistically significant difference was found between the mean RNFL, 1000 µm nasal, or 1000 µm temporal choroid thicknesses of the COPD patients and the control group (p=0.263, p=0.455, and p=0.611, resp.).

CONCLUSION

Decreased subfoveal choroid thickness was found in the COPD patients both during an exacerbation and in the stable period, when compared to the control group. The mean RNFL thickness was similar in the exacerbation and stable period of the stable COPD patients when compared to the control group. This suggests that ocular findings might be important in terms of COPD morbidity. This trial is registered with www.chictr.org.cn/enIndex.aspx.

COPD as an endothelial disorder: endothelial injury linking lesions in the lungs and other organs? (2017 Grover Conference Series)

Chronic obstructive pulmonary disease (COPD) is characterized by chronic expiratory airflow obstruction that is not fully reversible. COPD patients develop varying degrees of emphysema, small and large airway disease, and various co-morbidities. It has not been clear whether these co-morbidities share common underlying pathogenic processes with the pulmonary lesions. Early research into the pathogenesis of COPD focused on the contributions of injury to the extracellular matrix and pulmonary epithelial cells. More recently, cigarette smoke-induced endothelial dysfunction/injury have been linked to the pulmonary lesions in COPD (especially emphysema) and systemic co-morbidities including atherosclerosis, pulmonary hypertension, and chronic renal injury. Herein, we review the evidence linking endothelial injury to COPD, and the pathways underlying endothelial injury and the "vascular COPD phenotype" including: (1) direct toxic effects of cigarette smoke on endothelial cells; (2) generation of auto-antibodies directed against endothelial cells; (3) vascular inflammation; (4) increased oxidative stress levels in vessels inducing increases in lipid peroxidation and increased activation of the receptor for advanced glycation end-products (RAGE); (5) reduced activation of the anti-oxidant pathways in endothelial cells; (6) increased endothelial cell release of mediators with vasoconstrictor, pro-inflammatory, and remodeling activities (endothelin-1) and reduced endothelial cell expression of mediators that promote vasodilation and homeostasis of endothelial cells (nitric oxide synthase and prostacyclin); and (7) increased endoplasmic reticular stress and the unfolded protein response in endothelial cells. We also review the literature on studies of drugs that inhibit RAGE signaling in other diseases (angiotensin-converting enzyme inhibitors and angiotensin receptor blockers), or vasodilators developed for idiopathic pulmonary arterial hypertension that have been tested on cell culture systems, animal models of COPD, and/or smokers and COPD patients.

Worldwide prevalence of viral infection in AECOPD patients: A meta-analysis

BACKGROUND AND OBJECTIVE

Chronic obstructive pulmonary disease (COPD) is a chronic progressive lung disease. On the other hand, viral infections of the airway are associated with the acute exacerbations of COPD. A systematic review and meta-analysis were performed to determine the prevalence rate of viral infections in acute exacerbations of COPD patients.

METHODS

PubMed database was systematically searched for population-based prevalence studies (1930-2017). Fixed and random effects models were used for estimation of summary effect-sizes. Between-study heterogeneity and publication bias were also calculated. "Viral infections" and "COPD patients with exacerbations" were the two critical inclusion criteria.

RESULTS

Twenty-eight studies were selected out of 26078 articles for the present review. The overall estimation of the prevalence of viral infection was 0.374 (95% C.I: 0.359-0.388). Also, the evident heterogeneity of viral infection was observed among the studies (Cochran Q test, p value < 0.001 and I-squared = 97.5%). The highest and lowest prevalence rate was related to rhinovirus and echovirus, respectively. Also, the results of this study showed that the prevalence of viral infection in exacerbated COPD patients has fluctuation during the years with a slight increase and decrease.

CONCLUSIONS

The results of this systematic review demonstrated that respiratory viral infections have an important role in the acute exacerbation of COPD (AECOPD). In addition, determining the exact geographic epidemiology of these viruses is very important to manage the treatment of these infections.

Leg blood flow is impaired during small muscle mass exercise in patients with COPD

Skeletal muscle blood flow is regulated to match the oxygen demand and dysregulation could contribute to exercise intolerance in patients with chronic obstructive pulmonary disease (COPD). We measured leg hemodynamics and metabolites from vasoactive compounds in muscle interstitial fluid and plasma at rest, during one-legged knee-extensor exercise, and during arterial infusions of sodium nitroprusside (SNP) and acetylcholine (ACh), respectively. Ten patients with moderate to severe COPD and eight age- and sex-matched healthy controls were studied. During knee-extensor exercise (10 W), leg blood flow was lower in the patients compared with the controls (1.82 ± 0.11 vs. 2.36 ± 0.14 l/min, respectively; P < 0.05), which compromised leg oxygen delivery (372 ± 26 vs. 453 ± 32 ml O2/min, respectively; P < 0.05). At rest, plasma endothelin-1 (vasoconstrictor) was higher in the patients with COPD ( P < 0.05) and also tended to be higher during exercise ( P = 0.07), whereas the formation of interstitial prostacyclin (vasodilator) was only increased in the controls. There was no difference between groups in the nitrite/nitrate levels (vasodilator) in plasma or interstitial fluid during exercise. Moreover, patients and controls showed similar vasodilatory capacity in response to both endothelium-independent (SNP) and endothelium-dependent (ACh) stimulation. The results suggest that leg muscle blood flow is impaired during small muscle mass exercise in patients with COPD possibly due to impaired formation of prostacyclin and increased levels of endothelin-1.

NEW & NOTEWORTHY This study demonstrates that chronic obstructive pulmonary disease (COPD) is associated with a reduced blood flow to skeletal muscle during small muscle mass exercise. In contrast to healthy individuals, interstitial prostacyclin levels did not increase during exercise and plasma endothelin-1 levels were higher in the patients with COPD.

Evaluation of plasma leptin, tumor necrosis factor-α, and prealbumin as prognostic biomarkers during clinical recovery from acute exacerbations of chronic obstructive pulmonary disease

BACKGROUND

Inflammatory and nutritional biomarkers have an important bearing on outcomes of acute exacerbations of chronic obstructive pulmonary disease (AECOPD), but the temporal profile of these compounds during an acute episode is unclear.

PATIENTS AND METHODS

Plasma leptin, prealbumin, and tumor necrosis factor-alpha (TNF-α) were estimated at baseline and before hospital discharge in patients with AECOPD.

RESULTS

A total of 82 patients were evaluated (66 males; mean (standard deviation) age, 61.6 (10.1) years. Of these, 74 subjects (90.2%) were current or former smokers, with median (range) pack-years of 15 (0-96), duration of COPD of 8 years (range, 2-25 years) and duration of current symptoms being 5 days (range, 1-30 days). Majority (41.5%) had type I (severe) exacerbation. During the current episode, 46 patients (58.9%) required mechanical ventilation for a median of 6 days (range, 1-34). The median duration of hospital stay was 13 days, (range, 1-110). At discharge, significant reduction was observed in dyspnea, total leukocyte count, erythrocyte sedimentation rate (ESR), partial pressure of carbon dioxide, hemoglobin, urea, creatinine, potassium, aspartate transferase, and TNF-α levels compared to baseline, whereas arterial pH, PO₂, serum albumin, prealbumin, and leptin significantly improved. No difference was seen in leptin, prealbumin, and TNF-α between patients with mild/moderate and severe exacerbation, or between patients who required or did not require mechanical ventilation. Change in leptin correlated with body mass index and change in ESR; no associations were observed between leptin, prealbumin, and TNF-α with other clinico-laboratory variables.

CONCLUSION

Plasma levels of novel inflammatory and nutritional biomarkers, i.e., leptin, TNF-α, and prealbumin are altered in AECOPD episodes and lag behind other parameters during recovery. These biomarkers are not reliable predictors of clinical outcomes in these patients.

Pharmacological and genetic reappraisals of protease and oxidative stress pathways in a mouse model of obstructive lung diseases

Protease-antiprotease imbalance and oxidative stress are considered to be major pathophysiological hallmarks of severe obstructive lung diseases including chronic obstructive pulmonary disease (COPD) and cystic fibrosis (CF), but limited information is available on their direct roles in the regulation of pulmonary phenotypes. Here, we utilized βENaC-transgenic (Tg) mice, the previously established mouse model of severe obstructive lung diseases, to produce lower-mortality but pathophysiologically highly useful mouse model by backcrossing the original line with C57/BL6J mice. C57/BL6J-βENaC-Tg mice showed higher survival rates and key pulmonary abnormalities of COPD/CF, including mucous hypersecretion, inflammatory and emphysematous phenotypes and pulmonary dysfunction. DNA microarray analysis confirmed that protease- and oxidative stress-dependent pathways are activated in the lung tissue of C57/BL6J-βENaC-Tg mice. Treatments of C57/BL6J-βENaC-Tg mice with a serine protease inhibitor ONO-3403, a derivative of camostat methylate (CM), but not CM, and with an anti-oxidant N-acetylcystein significantly improved pulmonary emphysema and dysfunction. Moreover, depletion of a murine endogenous antioxidant vitamin C (VC), by genetic disruption of VC-synthesizing enzyme SMP30 in C57/BL6J-βENaC-Tg mice, exaggerated pulmonary phenotypes. Thus, these assessments clarified that protease-antiprotease imbalance and oxidative stress are critical pathways that exacerbate the pulmonary phenotypes of C57/BL6J-βENaC-Tg mice, consistent with the characteristics of human COPD/CF.

A Systematic Review of Diagnostic Biomarkers of COPD Exacerbation

The aims of this systematic review were to determine which blood-based molecules have been evaluated as possible biomarkers to diagnose chronic obstructive pulmonary disease (COPD) exacerbations (AECOPD) and to ascertain the quality of these biomarker publications. Patients of interest were those that have been diagnosed with COPD. MEDLINE, EMBASE, and CINAHL databases were searched systematically through February 2015 for publications relating to AECOPD diagnostic biomarkers. We used a modified guideline for the REporting of tumor MARKer Studies (mREMARK) to assess study quality. Additional components of quality included the reporting of findings in a replication cohort and the use of receiver-operating characteristics area-under-the curve statistics in evaluating performance. 59 studies were included, in which the most studied biomarkers were C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). CRP showed consistent elevations in AECOPD compared to control subjects, while IL-6 and TNF-α had variable statistical significance and results. mREMARK scores ranged from 6 to 18 (median score of 13). 12 articles reported ROC analyses and only one study employed a replication cohort to confirm biomarker performance. Studies of AECOPD diagnostic biomarkers remain inconsistent in their reporting, with few studies employing ROC analyses and even fewer demonstrating replication in independent cohorts.

Beta-blockers in COPD: time for reappraisal

The combined effects on the heart of smoking and hypoxaemia may contribute to an increased cardiovascular burden in chronic obstructive pulmonary disease (COPD). The use of beta-blockers in COPD has been proposed because of their known cardioprotective effects as well as reducing heart rate and improving systolic function. Despite the proven cardiac benefits of beta-blockers post-myocardial infarction and in heart failure they remain underused due to concerns regarding potential bronchoconstriction, even with cardioselective drugs. Initiating treatment with beta-blockers requires dose titration and monitoring over a period of weeks, and beta-blockers may be less well tolerated in older patients with COPD who have other comorbidities. Medium-term prospective placebo-controlled safety studies in COPD are warranted to reassure prescribers regarding the pulmonary and cardiac tolerability of beta-blockers as well as evaluating their potential interaction with concomitant inhaled long-acting bronchodilator therapy. Several retrospective observational studies have shown impressive reductions in mortality and exacerbations conferred by beta-blockers in COPD. However, this requires confirmation from long-term prospective placebo-controlled randomised controlled trials. The real challenge is to establish whether beta-blockers confer benefits on mortality and exacerbations in all patients with COPD, including those with silent cardiovascular disease where the situation is less clear.

Novel relationships of markers of monocyte activation and endothelial dysfunction with pulmonary dysfunction in HIV-infected persons

OBJECTIVE

Chronic obstructive pulmonary disease is a common comorbidity in HIV, with prevalence and severity of disease incompletely explained by risk factors such as smoking and age. Unique HIV-associated factors, including microbial translocation, monocyte activation, and endothelial dysfunction, have been described in other comorbidities, but have not been investigated in relation to pulmonary abnormalities in HIV. This study assessed the relationship of these pathologic processes to pulmonary function in HIV-infected and uninfected individuals and determined if relationships were unique to HIV.

DESIGN

Longitudinal observational study.

METHODS

Total 274 participants completed pulmonary function testing. Markers of inflammation (IL-6, IL-8, and TNFα), microbial translocation (lipopolysaccharide, sCD14), monocyte activation (sCD163, sCD14, and IL-2 receptor), and endothelial dysfunction (endothelin-1) were measured at baseline. Cross-sectional and longitudinal analyses were performed, adjusting for pertinent covariates.

RESULTS

In HIV-infected individuals, higher IL-6 and endothelin-1 associated with worse forced expiratory volume in one second (FEV1) percentage-predicted, and higher sCD163 associated with worse FEV1/forced vital capacity. IL-6, TNFα, lipopolysaccharide, sCD163, IL-2 receptor, and endothelin-1 associated with diffusing impairment. sCD163 and endothelin-1 interacted with HIV status in relationship to pulmonary function. In HIV-infected individuals only, baseline endothelin-1 was associated with lower FEV1, and sCD163 and endothelin-1 were associated with lower diffusing capacity during follow-up.

CONCLUSION

Circulating markers of HIV-associated humoral abnormalities are associated with airflow obstruction and diffusing impairment and baseline measures of monocyte activation and endothelial dysfunction associate with lower pulmonary function over time in HIV-infected persons. These findings suggest mechanisms of the disproportionate burden of chronic obstructive pulmonary disease in HIV-infected persons.

Influenza A virus infection and cigarette smoke impair bronchodilator responsiveness to β-adrenoceptor agonists in mouse lung

β2-adrenoceptor agonists are the mainstay therapy for patients with asthma but their effectiveness in cigarette smoke (CS)-induced lung disease such as chronic obstructive pulmonary disease (COPD) is limited. In addition, bronchodilator efficacy of β2-adrenoceptor agonists is decreased during acute exacerbations of COPD (AECOPD), caused by respiratory viruses including influenza A. Therefore, the aim of the present study was to assess the effects of the β2-adrenoceptor agonist salbutamol (SALB) on small airway reactivity using mouse precision cut lung slices (PCLS) prepared from CS-exposed mice and from CS-exposed mice treated with influenza A virus (Mem71, H3N1). CS exposure alone reduced SALB potency and efficacy associated with decreased β2-adrenoceptor mRNA expression, and increased tumour necrosis factor α (TNFα) and interleukin-1β (IL-1β) expression. This impaired relaxation was restored by day 12 in the absence of further CS exposure. In PCLS prepared after Mem71 infection alone, responses to SALB were transient and were not well maintained. CS exposure prior to Mem71 infection almost completely abolished relaxation, although β2-adrenoceptor and TNFα and IL-1β expression were unaltered. The present study has shown decreased sensitivity to SALB after CS or a combination of CS and Mem71 occurs by different mechanisms. In addition, the PCLS technique and our models of CS and influenza infection provide a novel setting for assessment of alternative bronchodilators.

Sputum endothelin-1 level is associated with active pulmonary tuberculosis and effectiveness of anti-tuberculosis chemotherapy

Pulmonary tuberculosis (TB) is a major global health problem. Endothelin (ET)-1 is an important pro-inflammatory factor in the airways, which acts as a chemoattractant and an upregulator of other inflammatory mediators. In the present study, the association of the sputum ET-1 level with active pulmonary TB and the effectiveness of anti-TB chemotherapy was explored for the first time. A total of 56 newly diagnosed patients with active pulmonary TB, 56 age- and gender-matched TB-free controls, and 43 subjects with latent TB were recruited to the study. Patients in the active TB group received standard anti-TB chemotherapy. Sputum samples were collected from all study subjects at baseline (day 0) and on days 1, 2, 4, 6, 10 and 14 of treatment for the active TB group and the ET-1 level was determined by enzyme-linked immunosorbent assay. The sputum ET-1 level in the active TB group was significantly higher than those in the latent TB and the non-TB groups at baseline. Following adjustment for confounders such as age, gender, severity of clinical presentation, plasma ET-1 level and comorbidities that might affect the sputum ET-1 level, multivariate logistic regression analysis revealed that sputum ET-1 level was an independent indicator for active pulmonary TB. In the active TB group during anti-TB chemotherapy, decrements in the sputum ET-1 level were in significant correlation with decrements in the number of colony-forming units and increments in the time to positivity in a Mycobacteria Growth Indicator Tube assay. In conclusion, this study indicates that an elevated sputum ET-1 level is an independent indicator of active pulmonary TB and suggests that decrements in the sputum ET-1 level could reflect the effectiveness of anti-TB chemotherapy.

Lack of Correlation Between Pulmonary and Systemic Inflammation Markers in Patients with Chronic Obstructive Pulmonary Disease: A Simultaneous, Two-Compartmental Analysis

INTRODUCTION

The origin of systemic inflammation in chronic obstructive pulmonary disease (COPD) patients remains to be defined, but one of the most widely accepted hypothesis is the 'spill over' of inflammatory mediators from the lung to the circulation.

OBJECTIVE

To evaluate the relationship between pulmonary and systemic inflammation in COPD quantifying several inflammatory markers in sputum and serum determined simultaneously.

METHODOLOGY

Correlations between various inflammatory variables (TNF-α, IL6, IL8) in sputum and serum were evaluated in 133 patients from the PAC-COPD cohort study. A secondary objective was the evaluation of relationships between inflammatory variables and lung function.

RESULTS

Inflammatory markers were clearly higher in sputum than in serum. No significant correlation was found (absolute value, r=0.03-0.24) between inflammatory markers in blood and in sputum. There were no significant associations identified between those markers and lung function variables, such as FEV1, DLCO and PaO2 neither.

CONCLUSIONS

We found no correlation between pulmonary and systemic inflammation in patients with stable COPD, suggesting different pathogenic mechanisms.

Targeting the IL-33/IL-13 Axis for Respiratory Viral Infections

Lung diseases, such as asthma and chronic obstructive pulmonary disease (COPD), are highly prevalent worldwide. One of the major factors that limits the efficacy of current medication in these patients are viral infections, leading to exacerbations of symptoms and decreased quality of life. Current pharmacological strategies targeting virus-induced lung disease are problematic due to antiviral resistance and the requirement for strain-specific vaccination. Thus, new therapeutic strategies are urgently required. In this Opinion article, we provide state-of-the-art evidence from humans and preclinical animal models implicating the interleukin (IL)-33/IL-13 axis in virus-induced lung disease. Thus, targeting the IL-33/IL-13 axis may be a feasible way to overcome the limitations of current therapy used to treat virus-induced exacerbations of lung disease.

Oxidative and Nitrosative Stress and Histone Deacetylase-2 Activity in Exacerbations of COPD

BACKGROUND

Respiratory virus infections are commonly associated with COPD exacerbations, but little is known about the mechanisms linking virus infection to exacerbations. Pathogenic mechanisms in stable COPD include oxidative and nitrosative stress and reduced activity of histone deacetylase-2 (HDAC2), but their roles in COPD exacerbations is unknown. We investigated oxidative and nitrosative stress (O&NS) and HDAC2 in COPD exacerbations using experimental rhinovirus infection.

METHODS

Nine subjects with COPD (Global Initiative for Chronic Obstructive Lung Disease stage II), 10 smokers, and 11 nonsmokers were successfully infected with rhinovirus. Markers of O&NS-associated cellular damage, and inflammatory mediators and proteases were measured in sputum, and HDAC2 activity was measured in sputum and bronchoalveolar macrophages. In an in vitro model, monocyte-derived THP-1 cells were infected with rhinovirus and nitrosylation and activity of HDAC2 was measured.

RESULTS

Rhinovirus infection induced significant increases in airways inflammation and markers of O&NS in subjects with COPD. O&NS markers correlated with virus load and inflammatory markers. Macrophage HDAC2 activity was reduced during exacerbation and correlated inversely with virus load, inflammatory markers, and nitrosative stress. Sputum macrophage HDAC2 activity pre-infection was inversely associated with sputum virus load and inflammatory markers during exacerbation. Rhinovirus infection of monocytes induced nitrosylation of HDAC2 and reduced HDAC2 activity; inhibition of O&NS inhibited rhinovirus-induced inflammatory cytokines.

CONCLUSIONS

O&NS, airways inflammation, and impaired HDAC2 may be important mechanisms of virus-induced COPD exacerbations. Therapies targeting these mechanisms offer potential new treatments for COPD exacerbations.

Vasoactive Intestinal Peptide for Diagnosing Exacerbation in Chronic Obstructive Pulmonary Disease

BACKGROUND

Vasoactive intestinal peptide (VIP) is the most abundant neuropeptide in the lung. VIP has been linked to pulmonary arterial hypertension and hypoxia.

OBJECTIVES

We aimed to assess circulating VIP levels at exacerbation and at stable chronic obstructive pulmonary disease (COPD) and to evaluate the diagnostic performance in a well-characterized cohort of COPD patients.

METHODS

The nested cohort study included patients with Global Initiative for Chronic Obstructive Lung Disease stage II-IV. Patients were examined at stable state and at acute exacerbation of COPD (AE-COPD), and dedicated serum was collected at both conditions. Serum VIP levels were determined by enzyme-linked immunosorbent assay. Diagnostic accuracy was analyzed by receiver operating characteristic curve and area under the curve (AUC).

RESULTS

Patients with acute exacerbation (n = 120) and stable COPD (n = 163) had similar characteristics at baseline. Serum VIP levels did not correlate with oxygen saturation at rest (p = 0.722) or at exercise (p = 0.168). Serum VIP levels were significantly higher at AE-COPD (130.25 pg/ml, 95% CI 112.19-151.83) as compared to stable COPD (40.07 pg/ml, 95% CI 37.13-43.96, p < 0.001). The association of increased serum VIP with AE-COPD remained significant after propensity score matching (p < 0.001). Analysis of the Youden index indicated the optimal serum VIP cutoff value as 56.6 pg/ml. The probability of AE-COPD was very low if serum VIP was ≤35 pg/ml (sensitivity >90%) and very high if serum VIP was ≥88 pg/ml (specificity >90%). Serum VIP levels presented a robust performance to diagnose AE-COPD (AUC 0.849, 95% CI 0.779-0.899).

CONCLUSIONS

Increased serum VIP levels are associated with AE-COPD.

Evaluation of arterial blood flow changes by orbital Doppler in chronic obstructive pulmonary disease and asthma

PURPOSE

Both chronic obstructive pulmonary disease (COPD) and asthma are important causes of morbidity and mortality worldwide. They primarily affect the lungs, but they have various extrapulmonary manifestations. The aim of our study was to evaluate the hemodynamic changes in orbital vessels of the patients with COPD and asthma using color Doppler ultrasonography and compare the results with healthy control subjects.

METHODS

Thirty-seven patients with COPD, 37 patients with asthma, and 41 healthy control subjects were included in this study. All patients with COPD were in moderate to severe group according to GOLD (Global Initiative for Chronic Obstructive Lung Disease), and similarly, all patients with asthma were in moderate to severe persistent group according to GINA (Global Initiative for Asthma) 2006 guidelines. End-tidal carbon dioxide, peripheral oxygen saturation, pulse rate, and respiratory rate were measured by using pulse oximeter in all patients. Measurements were performed in only 1 randomly selected eye of each participant. The peak systolic velocity, end diastolic velocity, and resistance index were measured in the central retinal artery, temporal posterior ciliary artery, and nasal posterior ciliary artery using the color Doppler ultrasonography technique.

RESULTS

The peak systolic velocity, end diastolic velocity, and resistance index values of temporal posterior ciliary artery and nasal posterior ciliary artery were significantly higher in COPD and asthma than in the control subjects. There was no difference between asthma and COPD.

CONCLUSIONS

We concluded that retrobulbar hemodynamics change in COPD and asthma is showing 1 of the systemic effects in these diseases.

Cytokine response to the 6-min walk test in individuals with different degrees of COPD

BACKGROUND AND AIM

Physical exercise is a key part of rehabilitation programs in chronic obstructive pulmonary disease (COPD) patients, although it could modulates immune system responses by altering the cytokine profile of such individuals. Furthermore, the degree of severity of COPD could influence the inflammatory response induced by exercise. To evaluate the cytokine profile of individuals with different degrees of COPD in response to a 6-min walk test (6MWT).

METHODS

Forty-one patients with COPD were classified according to the severity of the disease by Global Initiative for Chronic Obstructive Lung Disease method: moderate = 14 individuals; severe = 14 individuals; very severe = 13 individuals. Blood sample collection was performed in the subjects pre and post a 6MWT. Cytokine plasma levels were analyzed to determine the cytokine profile using a Cytometric Bead Array technique (Becton Dickinson, San Jose, CA, USA) assay in flow cytometry.

RESULTS

A significant difference was observed in the interleukin (IL)-6 levels after test between very severe and severe groups (P = 0.036). Also, lower levels of IL-4 were observed in the severe group compared with the very severe and the moderate groups in the pretest (P = 0.029; P = 0.003, respectively), and different values between the moderate and severe groups in the post-test (P = 0.044). A significant time pre-post effect was found in the IL-4 levels on the very severe group (P = 0.046).

CONCLUSION

After the 6MWT, a discrete inflammatory response was observed in COPD patients, independent of the degree of severity. The results concerning IL-4 and IL-6 levels can be indicative of an attempt to control inflammation after the 6MWT in COPD patients.

Color Doppler Evaluation of the Retrobulbar Hemodynamic Changes in Chronic Obstructive Pulmonary Disease: COPD and Retrobulbar Hemodynamic Changes

The aim of this study was to evaluate the hemodynamic changes in the extraocular orbital vessels of the patients with chronic obstructive pulmonary disease (COPD), using color Doppler ultrasonography, and to compare the results with those of healthy control subjects. The control group consisted of 35 healthy subjects who had no systemic problems, while the study group consisted of 60 patients with the diagnosis of COPD. Patients with COPD were grouped according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD). Twenty patients of stage 1 COPD (mild airflow limitation), stage 2 COPD (moderate airflow limitation), or stage 3 COPD (severe airflow limitation) were included in the groups 1, 2, and 3, respectively. Measurements were performed in both eyes of each participant. Peak systolic velocity (PSV), end-diastolic velocity (EDV), resistance index (RI), and pulsatility index (PI) were measured in the ophthalmic artery (OA), central retinal artery (CRA), and posterior ciliary artery (PCA). The RI and PI measurements of the OA, CRA, and PCA were significantly higher in group 3 when compared to the control group and groups 1 and 2. These significances were not observed when PSV and EDV values were compared. There were also no significant differences between groups 1, 2, and control patients, when mean PSV, EDV, RI, and PI values of all arteries were compared. None of the above parameters showed statistical significance when mean RI, PI, PSV, and EDV were compared between left and right eyes. Severe (stage 3) COPD is associated with impaired retrobulbar hemodynamics. Increased hypoxia and vascular mediators may be suggested in etiology.

Cytokine inhibition in the treatment of COPD

Cytokines play an important part in many pathobiological processes of chronic obstructive pulmonary disease (COPD), including the chronic inflammatory process, emphysema, and altered innate immune response. Proinflammatory cytokines of potential importance include tumor necrosis factor (TNF)-α, interferon-γ, interleukin (IL)-1β, IL-6, IL-17, IL-18, IL-32, and thymic stromal lymphopoietin (TSLP), and growth factors such as transforming growth factor-β. The current objectives of COPD treatment are to reduce symptoms, and to prevent and reduce the number of exacerbations. While current treatments achieve these goals to a certain extent, preventing the decline in lung function is not currently achievable. In addition, reversal of corticosteroid insensitivity and control of the fibrotic process while reducing the emphysematous process could also be controlled by specific cytokines. The abnormal pathobiological process of COPD may contribute to these fundamental characteristics of COPD, and therefore targeting cytokines involved may be a fruitful endeavor. Although there has been much work that has implicated various cytokines as potentially playing an important role in COPD, there have been very few studies that have examined the effect of specific cytokine blockade in COPD. The two largest studies that have been reported in the literature involve the use of blocking antibody to TNFα and CXCL8 (IL-8), and neither has provided benefit. Blocking the actions of CXCL8 through its CXCR2 receptor blockade was not successful either. Studies of antibodies against IL-17, IL-18, IL-1β, and TSLP are currently either being undertaken or planned. There is a need to carefully phenotype COPD and discover good biomarkers of drug efficacy for each specific target. Specific groups of COPD patients should be targeted with specific anticytokine therapy if there is evidence of high expression of that cytokine and there are features of the clinical expression of COPD that will respond.

Experimental rhinovirus infection in COPD: implications for antiviral therapies

•

COPD exacerbations are a major cause of morbidity and mortality; new treatments are urgently needed.

•

Respiratory viruses, particularly rhinoviruses, are a major cause of exacerbations.

•

Experimental rhinovirus infection is a valid model of virus-induced COPD exacerbations.

•

This model could be used to evaluate new antiviral treatments in COPD.

Chronic obstructive pulmonary disease (COPD) is a major public health problem and will be one of the leading global causes of mortality over the coming decades. Much of the morbidity, mortality and health care costs of COPD are attributable to acute exacerbations, the commonest causes of which are respiratory infections. Respiratory viruses are frequently detected in COPD exacerbations but direct proof of a causative relationship has been lacking. We have developed a model of COPD exacerbation using experimental rhinovirus infection in COPD patients and this has established a causative relationship between virus infection and exacerbations. In addition it has determined some of the molecular mechanisms linking virus infections to COPD exacerbations and identified potential new therapeutic targets. This new data should stimulate research into the role of antiviral agents as potential treatments for COPD exacerbations. Testing of antiviral agents has been hampered by the lack of a small animal model for rhinovirus infection and experimental rhinovirus infection in healthy volunteers has been used to test treatments for the common cold. Experimental rhinovirus infection in COPD subjects offers the prospect of a model that can be used to evaluate the effects of new treatments for virus-induced COPD exacerbations, and provide essential data that can be used in making decisions regarding large scale clinical trials.

Significance of the microbiome in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is one of few chronic disorders with rising mortality and morbidity. It is a highly prevalent disorder, characterized by highly heterogeneous clinical symptoms, health status, and disease progression. COPD is also characterized by an inflammatory/immune response that persists despite smoking cessation and varies by the patient population, method of assessment, and timing of measurement. Bacterial colonization or infection is ubiquitous in patients with COPD and, until recently, has been predominantly assessed using culture-based methodologies. This colonization has been believed to be biologically relevant. It has been estimated that more than 70% of the bacterial species on body surfaces cannot be cultured by standard techniques. As such, advanced culture-independent techniques have been developed that target bacterial genes, such as the 16S ribosomal RNA gene, that function as molecular chronometers. Application of these techniques in patients with COPD has suggested microbial diversity that varies by age, disease severity, and medication use. All of these data provide unique and rapidly evolving insight into the potential role of the respiratory microbiome in disease genesis and expression.

Pulmonary biomarkers in COPD exacerbations: a systematic review

Exacerbations of COPD (ECOPD) represent a major burden for patients and health care systems. Innovative sampling techniques have led to the identification of several pulmonary biomarkers. Although some molecules are promising, their usefulness in clinical practice is not yet established. Medline and Highwire databases were used to identify studies evaluating pulmonary sampled biomarkers in ECOPD. We combined 3 terms for ECOPD, 3 for biomarkers and 6 for the sampling method. Seventy-nine studies were considered eligible for inclusion in the review and were analyzed further. Pulmonary biomarkers sampled with non-invasive, semi-invasive and invasive methods were evaluated for their potential to illustrate the disease's clinical course, to correlate to clinical variables and to predict clinical outcomes, ECOPD etiology and response to treatment. According to published data several pulmonary biomarkers assessed in ECOPD have the potential to illustrate the natural history of disease through the modification of their levels. Among the clinically relevant molecules, those that have been studied the most and appear to be promising are spontaneous and induced sputum biomarkers for reflecting clinical severity and symptomatic recovery, as well as for directing towards an etiological diagnosis. Current evidence on the clinical usefulness of exhaled breath condensate and bronchoalveolar lavage biomarkers in ECOPD is limited. In conclusion, pulmonary biomarkers have the potential to provide information on the mechanisms underlying ECOPD, and several correlate with clinical variables and outcomes. However, on the basis of published evidence, no single molecule is adequately validated for wide clinical use. Clinical trials that incorporate biomarkers in decisional algorithms are required.

Effect of acute exacerbations on circulating endothelial, clotting and fibrinolytic markers in COPD patients

Patients with chronic obstructive pulmonary disease (COPD) are prone to clinical exacerbations that are associated with increased airway inflammation, a potent pro-thrombotic stimulus. Limited information is available on the mechanisms underlying the putative alterations of the endothelial-coagulative system during acute exacerbations. The aim was to investigate whether the activation of the endothelial-coagulative system occurs in association with the acute inflammatory response of COPD exacerbation. We monitored the blood levels of surrogate markers of inflammation: interleukin-6 (IL-6); endothelium damage: von Willebrand's factor (vWF); clotting activation: D-dimer (D-D), and prothrombin fragment 1+2 (F1+2); fibrinolytic response: plasminogen activator inhibitor 1 (PAI-1), in COPD subjects, during hospital admission and after clinical resolution. In 30 COPD subjects, IL-6, vWF, D-D and F1+2 levels were elevated during exacerbation and decreased significantly at clinical stability (IL-6, p = 0.005; vWF, p < 0.001; D-D, p < 0.001; F1+2, p < 0.001). PAI-1 levels did not change at exacerbation compared to clinically stable situations. Positive correlations were observed between several of the markers measured. Elevation of IL-6, vWF, D-D and F1+2 levels during COPD exacerbations implies a strict association between acute inflammation, endothelial activation and clotting initiation. This was not associated with a change in PAI-1, implying an increase in the fibrinolytic response to inflammation. The pro-thrombotic nature of COPD exacerbations sustained by enhanced clotting activation appears to be mitigated by excessive fibrinolysis.