Chronic Obstructive Pulmonary Disease and the Cardiovascular System: Vascular Repair and Regeneration as a Therapeutic Target

Global Hemostasis Testing in Chronic Kidney Disease-Are They Better Predictors of Bleeding and Thrombosis Risk?

Chronic kidney disease (CKD) affects over 10% of the global population and significantly increases the risk of cardiovascular disease as well as arising bleeding. There are alterations in hemostasis, which are multifactorial, involving complex interactions between coagulation, platelets, and the vessel wall. Hemostasis evaluation in CKD is critical for the optimal management of patients. However, conventional coagulation testing and renal function do not fully reflect the hemostatic alterations and do not adequately represent the risk of bleeding and/or thrombosis in patients with CKD. Global hemostatic assays, including thrombin and fibrin generation assays, provide a more wholesome assessment of the process, including the interaction between procoagulants, anticoagulants, platelets, and fibrinolysis. This review critically appraises published studies reporting the use of global coagulation assays to evaluate hemostasis in patients with CKD, as well as associated clinical outcomes.

Low levels of DNA repair enzyme NEIL2 May exacerbate inflammation and genomic damage in subjects with stable COPD and during severe exacerbations

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory airway disease that is an independent risk factor for lung cancer. Reduction in NEIL2 function, a DNA glycosylase involved in DNA repair during transcription, has been associated with an increased incidence of malignancies in humans. NEIL2 knockout mouse models have demonstrated increased inflammation and oxidative DNA damage in the lungs after exposure to an inflammatory insult, but data are lacking regarding NEIL2 function in individuals with COPD. We investigated whether NEIL2 levels and oxidative DNA damage to the transcribed genome are reduced in individuals with stable COPD and during severe acute exacerbations of COPD (AECOPD).

METHODS

The study was conducted at a single center in the US. Eligible subjects underwent a one-time 30 cc venous blood draw. The population consisted of 50 adults: 16 with stable COPD, 11 hospitalized for AECOPD, and 23 individuals without lung disease (controls). We analyzed blood leukocytes for NEIL2 mRNA and DNA damage by RT‒qPCR and LA‒qPCR, respectively, in all groups. Plasma levels of seven biomarkers, CXCL1, CXCL8, CXCL9, CXCL10, CCL2, CCL11 and IL-6, were analyzed in the COPD groups using a magnetic bead panel (Millipore®).

RESULTS

The fold change in NEIL2 mRNA levels were lower in individuals with stable COPD and AECOPD than in controls (0.72 for COPD, p = 0.029; 0.407 for AECOPD, p < 0.001). The difference in NEIL2 mRNA expression between the stable COPD group and AECOPD group was also statistically significant (p < 0.001). The fold change in DNA lesions per 10 kb of DNA was greater in the stable COPD (9.38, p < 0.001) and AECOPD (15.81, p < 0.001) groups than in the control group. The difference in fold change was also greater in the AECOPD group versus stable COPD p < 0.024). Cytokine levels were not significantly different between the COPD groups. NEIL2 levels were correlated with plasma eosinophil levels in the stable COPD group (r = 0.737, p = 0.003).

CONCLUSIONS

NEIL2 mRNA levels are significantly reduced in individuals with COPD and may exacerbate DNA damage and inflammation. These results suggest a possible mechanism that increases inflammation and oxidative genomic damage in COPD.

CLINICAL TRIAL NUMBER

Not applicable.

Biological pathways and mechanisms linking COPD and cardiovascular disease

Cardiovascular disease (CVD) still poses a significant risk for morbidity and mortality in patients with chronic obstructive pulmonary disease (COPD). For a long time, among functional parameters, only the forced expiratory volume in 1 s (FEV1) has been considered as predictive of cardiovascular (CV) mortality especially in elderly patients in fact, there is evidence that reductions in lung function indices can increase the risk of ischaemic heart diseases and cerebrovascular diseases, independently from other risk factors. Now, there is considerable evidence suggesting that hypoxemia, systemic inflammation, oxidative stress and hyperinflation may lead to an early sub-clinical CV involvement in patients affected by COPD. Ageing in itself impacts specific aspects of the CV system, including reduced beta-adrenergic responsiveness, increased vagal tone and myocardial and vascular stiffness, endothelial dysfunction, diminished arterial baroreflex and compromised diastolic function. The complex involved interactions include ageing mechanisms as well as multiple known and unknown (e.g. genetic) risk factors. CVDs are leading causes of mortality in individuals with impaired lung function and the two entities commonly coexist with poor outcomes in patients experiencing both conditions. However, the precise mechanisms responsible for this association remain largely unknown. In this narrative review, we summarize current knowledge regarding the co-occurrence of COPD and CVD focusing on the shared biological pathways and biological mechanisms involved in these conditions.

Chronic Obstructive Pulmonary Disease and Type 2 Diabetes Mellitus: Complex Interactions and Clinical Implications

Chronic obstructive pulmonary disease (COPD) and type 2 diabetes mellitus (T2DM) are highly prevalent chronic conditions, frequently coexisting due to their shared pathophysiological mechanisms and risk factors. Epidemiological studies estimate that up to 30% of COPD patients have comorbid T2DM, contributing to worsened disease progression, more hospitalizations, and higher mortality rates. Systemic inflammation in COPD contributes to insulin resistance by increasing pro-inflammatory cytokines (TNF-α, IL-6, and CRP), which impair glucose metabolism and beta-cell function. Conversely, hyperglycemia in T2DM exacerbates oxidative stress, leading to endothelial dysfunction, reduced lung function, and impaired pulmonary repair mechanisms. A comprehensive narrative review was conducted to evaluate the interplay between COPD and T2DM, examining shared pathophysiological mechanisms, clinical consequences, and management strategies. The co-occurrence of COPD and T2DM accelerates disease development, elevates hospitalization rates, and deteriorates overall prognosis. Pharmacological interactions complicate illness treatment, requiring a multidisciplinary therapy strategy. Recent data underscore the need to integrate palliative care, facilitate shared decision-making, and provide psychological support to enhance patient outcomes. Efficient therapy of COPD-T2DM comorbidity necessitates a customized, interdisciplinary strategy that targets both respiratory and metabolic health. Preliminary prognostic dialogues, palliative care, and holistic lifestyle modifications can improve patient quality of life and clinical results.

Deep learning-driven pulmonary artery and vein segmentation reveals demography-associated vasculature anatomical differences

Pulmonary artery-vein segmentation is critical for disease diagnosis and surgical planning. Traditional methods rely on Computed Tomography Pulmonary Angiography (CTPA), which requires contrast agents with potential health risks. Non-contrast CT, a safer and more widely available approach, however, has long been considered impossible for this task. Here we propose High-abundant Pulmonary Artery-vein Segmentation (HiPaS), enabling accurate segmentation across both non-contrast CT and CTPA at multiple resolutions. HiPaS integrates spatial normalization with an iterative segmentation strategy, leveraging lower-level vessel segmentations as priors for higher-level segmentations. Trained on a multi-center dataset comprising 1073 CT volumes with manual annotations, HiPaS achieves superior performance (dice score: 91.8%, sensitivity: 98.0%) and demonstrates non-inferiority on non-contrast CT compared to CTPA. Furthermore, HiPaS enables large-scale analysis of 11,784 participants, revealing associations between vessel abundance and sex, age, and diseases, under lung-volume control. HiPaS represents a promising, non-invasive approach for clinical diagnostics and anatomical research.

Unmasking Cardiovascular Risk in Patients with COPD at Primary Care Settings: The Critical Role of Age, Sex, and Smoking

Background: Chronic obstructive pulmonary disease (COPD) is a progressive respiratory condition frequently associated with cardiovascular comorbidities, including ischemic heart disease (IHD), heart failure (HF), and atrial fibrillation (AF). These conditions significantly impact patient outcomes, yet their prevalence and risk factors remain underexplored in primary care settings. This study investigates the role of age, sex, and smoking status in the prevalence of IHD, HF, and AF among patients with COPD managed in general practice settings. Methods: A retrospective analysis was conducted using de-identified electronic health records from eleven general practitioner (GP) practices in Northern Ireland. Patients with COPD were identified through the Quality and Outcomes Framework (QOF) register, and the presence of IHD, HF, and AF was recorded. Statistical analyses included chi-square tests and independent t-tests to examine associations between cardiovascular comorbidities and patient demographics, with significance set at p < 0.05. Results: Among the total registered population of 77,797, there were 1575 patients with COPD, of whom 335 had IHD, 211 had AF, and 116 had HF. Patients with COPD had a significantly higher prevalence of IHD, AF, and HF compared to those without COPD. Age was a strong determinant, with older age groups, particularly those over 75 years, showing a markedly higher prevalence of all three conditions. Sex analysis revealed that male patients with COPD were significantly more likely to have IHD, AF, and HF than females. However, the association between smoking status and the presence of HF, IHD, or AF was not significantly different between current/ex-smokers and non-smokers. Conclusions: The findings highlight the high burden of cardiovascular comorbidities among patients with COPD in primary care and emphasise the need for routine cardiovascular screening. Given the strong influence of age and sex, targeted risk assessment and management strategies should be prioritised for older and male patients with COPD. The lack of association between smoking and cardiovascular comorbidities suggests that additional risk factors should be considered in cardiovascular risk assessment. A more integrated approach to managing COPD and cardiovascular conditions within general practice settings is essential to improve patient outcomes. Future research should focus on evaluating interventions that enhance early detection and multidisciplinary management of cardiovascular comorbidities in patients with COPD.

Prevalence and clinical correlates of chronic obstructive pulmonary disease in heart failure patients: a cross-sectional study in China

Background

Despite chronic obstructive pulmonary disease's (COPD)'s prevalence in the general populace, its incidence in heart failure (HF) patients is understudied. This study aimed to assess COPD prevalence and clinical associations in Chinese HF patients.

Methods

From the Chinese Heart Failure Study, demographic and clinical details of 2008 HF patients were analyzed. Divided into 233 COPD cases and 1775 non-COPD controls, a multivariable logistic regression identified factors linked to COPD onset in HF, with thorough examination of intergroup clinical differences.

Results

The incidence of COPD in HF individuals was 11.60% (233/2008). The COPD subgroup featured a higher ratio of individuals over 60 and males, alongside lower systolic blood pressure (SBP), body mass index (BMI), higher Charlson Comorbidity Index (CCI) scores, and increased PaCO₂ levels (p < 0.05). Type II respiratory failure and right ventricular dysfunction (RVD) were more prevalent in the COPD subgroup (p < 0.001). Binary logistic regression, after adjustments, indicated positive associations between COPD and age over 60 (OR = 3.831, 95%CI: 1.085-13.526, p = 0.037), male sex (OR = 1.587, 95%CI: 1.032-2.441, p = 0.036), higher CCI (OR = 2.214, 95%CI: 1.796-2.729, p < 0.001), elevated PaCO2 (OR = 1.035, 95%CI: 1.015-1.055, p < 0.001), and RVD (OR = 0.605, 95%CI: 0.119-3.063, p = 0.544). Inversely, higher SBP (OR = 0.990, 95%CI: 0.982-0.998, p = 0.020) and log (triglycerides) (OR = 0.183, 95%CI: 0.064-0.552, p = 0.002) were negatively correlated with COPD in HF patients.

Conclusion

In a large cohort of Chinese Heart Failure (HF) patients, our study revealed a notable COPD prevalence. Key risk factors included age, sex, elevated PaCO2, CCI score, and right heart failure, while higher SBP and triglyceride levels offered protection. These insights lay groundwork for probing disease mechanisms and therapeutic approaches.

Pathophysiology of Group 3 Pulmonary Hypertension Associated with Lung Diseases and/or Hypoxia

Pulmonary hypertension associated with lung diseases and/or hypoxia is classified as group 3 in the clinical classification of pulmonary hypertension. The efficacy of existing selective pulmonary vasodilators for group 3 pulmonary hypertension is still unknown, and it is currently associated with a poor prognosis. The mechanisms by which pulmonary hypertension occurs include hypoxic pulmonary vasoconstriction, pulmonary vascular remodeling, a decrease in pulmonary vascular beds, endothelial dysfunction, endothelial-to-mesenchymal transition, mitochondrial dysfunction, oxidative stress, hypoxia-inducible factors (HIFs), inflammation, microRNA, and genetic predisposition. Among these, hypoxic pulmonary vasoconstriction and subsequent pulmonary vascular remodeling are characteristic factors involving the pulmonary vasculature and are the focus of this review. Several factors have been reported to mediate vascular remodeling induced by hypoxic pulmonary vasoconstriction, such as HIF-1α and mechanosensors, including TRP channels. New therapies that target novel molecules, such as mechanoreceptors, to inhibit vascular remodeling are awaited.

Unraveling the Role of Oxygen Pulse Variability in Endurance Exercise Training in Individuals with COPD: A Novel Approach to Response of Oxygen Pulse and Quality of Life in Pulmonary Rehabilitation

Background

Chronic obstructive pulmonary disease (COPD) is characterized by airway inflammation, airflow limitation, reduced health-related quality of life (HRQL), and exercise intolerance. Pulmonary rehabilitation (PR) is essential for COPD management, but outcomes may be influenced by individual physiological factors. Cardiopulmonary exercise testing (CPET) measures oxygen pulse (O2P), an indicator of stroke volume, yet the impact of baseline O2P on PR effectiveness remains unclear.

Methods

This retrospective study included 97 participants with COPD who had received PR, of whom 48 were classified as Group 1 (normal O2P) and 49 as Group 2 (low O2P). PR involved 12 weeks of hospital-based endurance training on a bike, performed twice a week. Participants were assessed before and after PR using spirometry, respiratory muscle strength measurements, CPET, and HRQL evaluation with the St. George's Respiratory Questionnaire (SGRQ).

Results

PR significantly improved exercise capacity (peak work rate and oxygen consumption), dyspnea score, and all domains of the SGRQ, maximum expiratory pressure, ventilatory equivalent, respiratory rate, and mean blood pressure at rest in both groups (p < 0.05). However, improvements in O2P, maximal inspiratory pressure, and tidal volume at rest were observed only in Group 2 but not in Group 1.

Conclusion

PR improves exercise capacity, HRQL and specific respiratory function in participants with COPD, regardless of baseline O2P levels. Individuals with lower baseline O2P experience more benefits from PR, including a significant increase in O2P.

Endothelial progenitor cells and chronic obstructive pulmonary disease: From basic research to clinical application

Chronic obstructive pulmonary disease (COPD) is a chronic lung disease characterized by persistent airflow limitation, with vascular endothelial dysfunction being one of its key pathogenic mechanisms. Endothelial progenitor cells (EPCs), a class of progenitor cells capable of vascular repair and regeneration, play a crucial role in the pathogenesis of COPD. In COPD patients, the number and function of circulating EPCs are significantly reduced, which is closely associated with disease severity, lung function decline, acute exacerbations, nutritional status, and comorbidities. Environmental factors such as smoking, nicotine, electronic cigarettes, and particulate matter 2.5 (PM2.5) can markedly impair both the function and quantity of EPCs. The underlying mechanisms may involve the regulation of vascular endothelial growth factor/vascular endothelial growth factor receptor (VEGF/VEGFR), C-X-C motif chemokine ligand 12/C-X-C motif chemokine receptor 4 (CXCL12/CXCR4) signaling pathways, and various cytokine regulations. Moreover, animal studies have shown that intratracheal transplantation of EPCs can significantly improve lung function and pathological changes in emphysema models, suggesting that targeting EPCs may be a promising therapeutic strategy for COPD. Elucidating the molecular mechanisms of EPC mobilization, homing, and dysfunction, and evaluating the efficacy and safety of their clinical application, may offer new insights into the treatment of COPD and other chronic lung diseases.

Efficacy of a hydrogen-oxygen generator in treating cigarette smoke-induced chronic obstructive pulmonary disease in rats

Current treatments for chronic obstructive pulmonary disease (COPD), a common respiratory condition, include oxygen therapy and steroids for temporary relief. In this study, we established a rat model of cigarette smoke (CS)-induced COPD and investigated the benefits of a hydrogen-oxygen generator in this model. CS-exposed rats were treated using either a hydrogen-oxygen generator or a steroid. A hydrogen-oxygen generator reduced the neutrophil, lymphocyte, and eosinophil counts compared to natural recovery, whereas steroid treatment increased the total white blood cell, neutrophil, lymphocyte, monocyte and eosinophil counts. Furthermore, the mean linear intercept and the mean alveolar number were 59.8%, and 188.3%, respectively, after treatment with the generator, compared to the values observed with natural recovery. Finally, the generator increased the tricuspid annular plane systolic excursion values by 113.1% compared with the values in natural recovery. Our findings indicate successful establishment of a rat model of CS-induced COPD and demonstrate the potential benefits of using a hydrogen-oxygen generator for COPD patients.

Analysis of COPD: Distinguishing Characteristics and Management of Smoking vs Never Smoking Patients

Background

Chronic obstructive pulmonary disease (COPD) is a significant public health issue characterized by gradually worsening airflow limitation. It is a leading cause of mortality and morbidity worldwide, yet research on COPD patients who have never smoked is limited. This study aims to document the demographic, symptomatic, and therapeutic characteristics of COPD patients receiving outpatient pulmonary care in Hungary, focusing on smoking history, and evaluate their distribution according to the GOLD A/B/E classification.

Methods

The study recorded demographic data, symptom severity, occurrence of severe and moderate exacerbations, treatment, comorbidities, quality of life, and COVID-19 vaccination status among COPD patients from November 2021 to January 2023. A total of 6974 patients were categorized into current smokers, former smokers, and never smokers.

Results

Patients had an average age of 67.2±8.9 years, with 48.2% male and 51.8% female. Of participants, 86.1% had a smoking history, while 13.9% had never smoked. COPD patients who had never smoked showed significantly better quality of life (CAT: 15.2±7.6 vs 15.8±6.9; p=0.006), oxygen saturation (SpO2%: 96.7±2.3 vs 95.8±2.4; p<0.001), higher body mass index (BMI: 29.4±5.9 vs 27.1±6.3; p<0.001), and better lung function (FEV1ref%: 67.9±20.7 vs 58.9±18.1; p<0.001) compared to smokers. However, non-smoking COPD patients had a higher frequency of comorbidities (3.5±2.2 vs 2.9±2.1; p<0.05). These differences may arise from complex genetic and environmental interactions.

Conclusion

COPD patients who have never smoked exhibited better quality of life, nutritional status, and lung function compared to smokers, indicating the need for tailored treatment approaches. Further long-term studies are essential to validate these differences in quality of life and lung function between smoking and non-smoking COPD patients.

Alleviatory Role of Panax Notoginseng Saponins in Modulating Inflammation and Pulmonary Vascular Remodeling in Chronic Obstructive Pulmonary Disease: mechanisms and Implications

COPD is an inflammatory lung disease that limits airflow and remodels the pulmonary vascular system. This study delves into the therapeutic potential and mechanistic underpinnings of Panax notoginseng Saponins (PNS) in alleviating inflammation and pulmonary vascular remodeling in a COPD rat model. Symmap and ETCM databases provided Panax notoginseng-related target genes, and the CTD and DisGeNET databases provided COPD-related genes. Intersection genes were subjected to protein-protein interaction analysis and pathway enrichment to identify downstream pathways. A COPD rat model was established, with groups receiving varying doses of PNS and a Roxithromycin control. The pathological changes in lung tissue and vasculature were examined using histological staining, while molecular alterations were explored through ELISA, RT-PCR, and Western blot. Network pharmacology research suggested PNS may affect the TLR4/NF-κB pathway linked to COPD development. The study revealed that, in contrast to the control group, the COPD model exhibited a significant increase in inflammatory markers and pathway components such as TLR4, NF-κB, HIF-1α, VEGF, ICAM-1, SELE mRNA, and serum TNF-α, IL-8, and IL-1β. Treatment with PNS notably decreased these markers and mitigated inflammation around the bronchi and vessels. Taken together, the study underscores the potential of PNS in reducing lung inflammation and vascular remodeling in COPD rats, primarily via modulation of the TLR4/NF-κB/HIF-1α/VEGF pathway. This research offers valuable insights for developing new therapeutic strategies for managing and preventing COPD.

Mechanisms Controlling the Behavior of Vascular Smooth Muscle Cells in Hypoxic Pulmonary Hypertension

Pulmonary hypertension is a complex and heterogeneous condition with five main subtypes (groups). This review focuses on pulmonary hypertension caused by chronic hypoxia (hypoxic pulmonary hypertension, HPH, group 3). It is based mainly on our own experimental work, especially our collaboration with the group of Professor Herget, whose fifth anniversary of death we commemorate. We have found that oxidation and degradation of the extracellular matrix (ECM) in vitro, in either the presence or the absence of pro-inflammatory cells, activate vascular smooth muscle cell (VSMC) proliferation. Significant changes in the ECM of pulmonary arteries also occurred in vivo in hypoxic rats, namely a decrease in collagen VI and an increase in matrix metalloproteinase 9 (MMP-9) in the tunica media, which may also contribute to the growth activation of VSMCs. The proliferation of VSMCs was also enhanced in their co-culture with macrophages, most likely due to the paracrine production of growth factors in these cells. However, hypoxia itself has a dual effect: on the one hand, it can activate VSMC proliferation and hyperplasia, but on the other hand, it can also induce VSMC hypertrophy and increased expression of contractile markers in these cells. The influence of hypoxia-inducible factors, microRNAs and galectin-3 in the initiation and development of HPH, and the role of cell types other than VSMCs (endothelial cells, adventitial fibroblasts) are also discussed. Keywords: Vasoconstriction, Remodeling, Oxidation, Degradation, Extracellular matrix, Collagen, Proteolytic enzymes, Metalloproteinases, Macrophages, Mast cells, Smooth muscle cells, Endothelial cells, Fibroblasts, Mesenchymal stem cells, Hypoxia-inducible factor, microRNA, Galectins, Hyperplasia, Hypertrophy, Therapy of hypoxic pulmonary hypertension.

Temporal Dynamics of Cardiovascular Risk in Patients with Chronic Obstructive Pulmonary Disease During Stable Disease and Exacerbations: Review of the Mechanisms and Implications

Introduction

Exacerbations of chronic obstructive pulmonary disease (COPD) are risk factors for severe cardiovascular (CV) events, with the risk remaining significantly elevated long after the symptomatic phase of the exacerbation. The pathophysiology underpinning the relationship between acute events of both COPD and CV diseases has been understudied. Our objectives were to review the mechanisms by which COPD exacerbations increase the risk of CV events and understand the temporality of this risk.

Methods

A pragmatic and targeted literature review was conducted with a focus on identifying recent, high-impact papers up to June 2023, guided by insights from subject matter experts including pulmonologists and cardiologists.

Results

A substantial number of inter-related mechanisms underpin the spiral of anatomical and functional deterioration of lung and heart affecting COPD patients during stable state. In turn, an exacerbation of COPD may trigger a CV event, during and beyond the symptomatic phase, due to ventilation/perfusion mismatch, oxygen supply-demand imbalance, oxidative stress, systemic inflammation, hypercoagulable state, dynamic hyperinflation, pulmonary hypertension, and sympathetic activation. However, no study was identified that explored the mechanisms by which an exacerbation confers a sustained risk of CV event.

Conclusion

While our review identified multiple dynamic and interacting pathophysiological mechanisms during and after an exacerbation of COPD that contribute to increasing the risk of a wide range of cardiac events, little is known regarding the precise long-term mechanisms after acute exacerbation to explain the persistent increased CV event risk beyond the symptomatic phase. The temporal changes in static and dynamic substrates need further characterization to better understand the different risk factors and risk periods for a CV event following the onset of an exacerbation. Moreover, guideline-directed cardiopulmonary therapies should be implemented at every opportunity; preventing exacerbations and intensively treating traditional CV risk factors should be a focus in COPD management.

Interplay between Lung Diseases and Viral Infections: A Comprehensive Review

The intricate relationship between chronic lung diseases and viral infections is a significant concern in respiratory medicine. We explore how pre-existing lung conditions, including chronic obstructive pulmonary disease, asthma, and interstitial lung diseases, influence susceptibility, severity, and outcomes of viral infections. We also examine how viral infections exacerbate and accelerate the progression of lung disease by disrupting immune responses and triggering inflammatory pathways. By summarizing current evidence, this review highlights the bidirectional nature of these interactions, where underlying lung diseasesincrease vulnerability to viral infections, while these infections, in turn, worsen the clinical course. This review underscores the importance of preventive measures, such as vaccination, early detection, and targeted therapies, to mitigate adverse outcomes in patients with chronic lung conditions. The insights provided aim to inform clinical strategies that can improve patient management and reduce the burden of chronic lung diseases exacerbated by viral infections.

Suppression of the DNA repair enzyme NEIL2 promotes persistent inflammation and genomic damage in subjects with stable COPD and during severe exacerbations

Background

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory airway disease that is an independent risk factor for lung cancer. NEIL2, a DNA glycolase involved in DNA repair during transcription, has also been associated with an increased incidence of malignancies in humans. NEIL2 knockout mouse models have demonstrated increased inflammation and oxidative DNA damage in the lungs after exposure to an inflammatory insult, but data are lacking regarding NEIL2 function in individuals with stable COPD and during severe acute exacerbations of COPD (AECOPD). We investigated whether NEIL2 levels and oxidative DNA damage to the transcribed genome are altered in individuals with stable COPD and AECOPD.

Methods

The study was conducted at a single center in the US. Eligible subjects underwent a one-time 30 cc venous blood draw. The population consisted of 50 adults: 16 with stable COPD, 11 hospitalized for AECOPD, and 23 volunteers. We analyzed blood leukocytes for NEIL2 mRNA and DNA damage by RT-qPCR and LA-qPCR, respectively, in all groups. Plasma levels of seven biomarkers, CXCL1, CXCL8, CXCL9, CXCL10, CCL2, CCL11 and IL-6, were analyzed in the COPD groups using a magnetic bead panel (Millipore®).

Results

The NEIL2 mRNA levels were lower in individuals with stable COPD and AECOPD than in controls (0.72 for COPD, p = 0.0289; 0.407 for AECOPD, p = 0.0002). The difference in NEIL2 mRNA expression between the stable COPD group and AECOPD group was also statistically significant (p < 0.001). The fold change in DNA lesions per 10 kb of DNA was greater in the stable COPD (9.38, p < 0.0008) and AECOPD (15.81, p < 0.0004) groups than in the control group. The difference in fold change was also greater in the AECOPD group versus stable COPD p < 0.0236). Biomarker levels were not significantly different between the COPD groups. NEIL2 levels were correlated with plasma eosinophil levels in the stable COPD group (r = 0.737, p < 0.0027).

Conclusions

NEIL2 mRNA levels are significantly reduced in COPD subjects and are associated with increased DNA damage and inflammation. These results reveal a mechanism that promotes persistent airway inflammation and oxidative genomic damage and increases the risk of malignancy in this population.

Altered hypoxia-induced cellular responses and inflammatory profile in lung fibroblasts from COPD patients compared to control subjects

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease characterized by chronic bronchitis, emphysema and vascular remodelling. The disease is associated with hypoxia, inflammation and oxidative stress. Lung fibroblasts are important cells in remodelling processes in COPD, as main producers of extracellular matrix proteins but also in synthesis of growth factors and inflammatory mediators.

METHODS

In this study we aimed to investigate if there are differences in how primary distal lung fibroblasts obtained from COPD patients and healthy subjects respond to hypoxia (1% O2) and pro-fibrotic stimuli with TGF-β1 (10 ng/mL). Genes and proteins associated with oxidative stress, endoplasmic reticulum stress, remodelling and inflammation were analysed with RT-qPCR and ELISA.

RESULTS

Hypoxia induced differences in expression of genes involved in oxidative stress (SOD3 and HIF-1α), ER stress (IRE1, PARK and ATF6), apoptosis (c-Jun and Bcl2) and remodelling (5HTR2B, Collagen7 and VEGFR2) in lung fibroblasts from COPD subjects compared to control subjects, where COPD fibroblasts were in general less responsive. The release of VEGF-C was increased after hypoxia, whereas TGF-β significantly reduced the VEGF response to hypoxia and the release of HGF. COPD fibroblasts had a higher release of IL-6, IL-8, MCP-1 and PGE2 compared to lung fibroblasts from control subjects. The release of inflammatory mediators was less affected by hypoxia, whereas TGFβ1 induced differences in inflammatory profile between fibroblasts from COPD and control subjects.

CONCLUSION

These results suggest that there is an alteration of gene regulation of various stress responses and remodelling associated mediator release that is related to COPD and hypoxia, where fibroblasts from COPD patients have a deficient response.

Impact of Smoking and Chronic Obstructive Pulmonary Disease on All-Cause, Respiratory, and Cardio-Cerebrovascular Mortality

Introduction

Mortality differences in chronic obstructive pulmonary disease (COPD) between nonsmokers and smokers remain unclear. We compared the risk of death associated with smoking and COPD on mortality.

Methods

The study included participants aged ≥40 years who visited pulmonary clinics and were categorised into COPD or non-COPD and smoker or nonsmoker on the basis of spirometry results and cigarette consumption. Mortality rates were compared between groups using statistical analysis for all-cause mortality, respiratory disease-related mortality, and cardiocerebrovascular disease-related mortality.

Results

Among 5811 participants, smokers with COPD had a higher risk of all-cause (adjusted hazard ratio (aHR), 1.69; 95% confidence interval (CI), 1.23-2.33) and respiratory disease-related mortality (aHR, 2.14; 95% CI, 1.20-3.79) than nonsmokers with COPD. Non-smokers with and without COPD had comparable risks of all-cause mortality (aHR, 1.39; 95% CI, 0.98-1.97) and respiratory disease-related mortality (aHR, 1.77; 95% CI, 0.85-3.68). However, nonsmokers with COPD had a higher risk of cardiocerebrovascular disease-related mortality than nonsmokers without COPD (aHR, 2.25; 95% CI, 1.15-4.40).

Conclusion

The study found that smokers with COPD had higher risks of all-cause mortality and respiratory disease-related mortality compared to nonsmokers with and without COPD. Meanwhile, nonsmokers with COPD showed comparable risks of all-cause and respiratory mortality but had a higher risk of cardiocerebrovascular disease-related mortality compared to nonsmokers without COPD.

Vascular Endothelial Damage in COPD: Where Are We Now, Where Will We Go?

BACKGROUND

Chronic obstructive pulmonary disease (COPD) has higher rates among the general population, so early identification and prevention is the goal. The mechanisms of COPD development have not been completely established, although it has been demonstrated that endothelial dysfunction plays an important role. However, to date, the measurement of endothelial dysfunction is still invasive or not fully established. Nailfold video capillaroscopy (NVC) is a safe, non-invasive diagnostic tool that can be used to easily evaluate the microcirculation and can show any possible endothelial dysfunctions early on. The aim of this review is to evaluate if nailfold microcirculation abnormalities can reflect altered pulmonary vasculature and can predict the risk of cardiovascular comorbidities in COPD patients.

METHODS

A systematic literature search concerning COPD was performed in electronic databases (PUBMED, UpToDate, Google Scholar, ResearchGate), supplemented with manual research. We searched in these databases for articles published until March 2024. The following search words were searched in the databases in all possible combinations: chronic obstructive pulmonary disease (COPD), endothelial damage, vascular impairment, functional evaluation, capillaroscopy, video capillaroscopy, nailfold video capillaroscopy. Only manuscripts written in English were considered for this review. Papers were included only if they were able to define a relationship between COPD and endothelium dysfunction.

RESULTS

The search selected 10 articles, and among these, only three previous reviews were available. Retinal vessel imaging, flow-mediated dilation (FMD), and skin autofluorescence (AF) are reported as the most valuable methods for assessing endothelial dysfunction in COPD patients.

CONCLUSIONS

It has been assumed that decreased nitric oxide (NO) levels leads to microvascular damage in COPD patients. This finding allows us to assume NVC's potential effectiveness in COPD patients. However, this potential link is based on assumption; further investigations are needed to confirm this hypothesis.

Multidisciplinary Management of Patients With Chronic Obstructive Pulmonary Disease and Cardiovascular Disease

Chronic obstructive pulmonary disease (COPD) and cardiovascular disease (CVD) frequently coexist, increasing the prevalence of both entities and impacting on symptoms and prognosis. CVD should be suspected in patients with COPD who have high/very high risk scores on validated scales, frequent exacerbations, precordial pain, disproportionate dyspnea, or palpitations. They should be referred to cardiology if they have palpitations of unknown cause or angina pain. COPD should be suspected in patients with CVD if they have recurrent bronchitis, cough and expectoration, or disproportionate dyspnea. They should be referred to a pulmonologist if they have rhonchi or wheezing, air trapping, emphysema, or signs of chronic bronchitis. Treatment of COPD in cardiovascular patients should include long-acting muscarinic receptor antagonists (LAMA) or long-acting beta-agonists (LABA) in low-risk or high-risk non-exacerbators, and LAMA/LABA/inhaled corticosteroids in exacerbators who are not controlled with bronchodilators. Cardioselective beta-blockers should be favored in patients with CVD, the long-term need for amiodarone should be assessed, and antiplatelet drugs should be maintained if indicated.

Exploring the importance of m5c in the diagnosis and subtype classification of COPD using the GEO database

BACKGROUND

5-Methylcytosine (m5C) is an mRNA modifier that is associated with the occurrence and development of viral infection, pulmonary fibrosis, lung cancer, and other diseases. However, the role of m5C regulators in chronic obstructive pulmonary disease (COPD) remains unknown.

METHODS

In this study, by analysing the GSE42057 dataset, the differential expression of m5c regulators in the COPD group and control group was obtained, and a correlation analysis was conducted. The random forest model and support vector machine model were used to predict the occurrence of COPD. A nomogram model was also constructed to predict the prevalence of COPD. The COPD patients were divided into subtypes by consistent cluster analysis based on m5c methylation regulators. Immune cell infiltration was performed on the m5c methylation subtypes. Differentially expressed genes (DEGs) between m5c methylation subtypes were screened, and the DEGs were analysed by Gene Ontology (GO) Kyoto Encyclopedia of Genes and Genomes (KEGG). Finally, we verified the expression of several m5C regulators and related pathways using a COPD cell model.

RESULTS

Seven m5c methylation regulators were differentially expressed. The random forest model based on the above genes was the most accurate for predicting the occurrence of COPD. A nomogram model based on the above genes could also accurately predict the prevalence of COPD, and the implementation of these models could benefit COPD patients. The consistent cluster analysis divided the COPD patients into two subtypes (Cluster A and Cluster B). The main component analysis algorithm determined the m5c methylation subtypes and found that patients in Cluster A had a higher m5c score than those in Cluster B. GO analysis of the DEGs between the m5c methylation COPD patient subtypes revealed that DEGS were mainly enriched in leukocyte-mediated immunity and regulation of T-cell activation. KEGG analysis revealed that DEGS were mainly enriched in Th1 and Th2 cell differentiation, neutrophil extracellular trap formation, and the NF-κB signalling pathway. Immunocyte correlation analysis revealed that Cluster B was associated with neutrophil- and macrophage-mediated immunity, while Cluster A was associated with CD4 + T-cell- and CD8 + T-cell-mediated immunity. Cell experiments have also verified some of the above research results.

CONCLUSION

The diagnosis and subtype classification of COPD patients based on m5c regulators may provide a new strategy for the diagnosis and treatment of COPD.

Effects of a physical exercise program on HIF-1α in people with Chronic Obstructive Pulmonary Disease living at high altitude: study protocol for a clinical trial

BACKGROUND

Chronic Obstructive Pulmonary Disease (COPD) is a chronic, noncommunicable disease characterized by hypoxemia, with altered lung function, dyspnea on mild exertion, limited tolerance to physical exertion, and functional impairment. Physical exercise has been recommended worldwide as an efficient strategy to improve the autonomy and quality of life of patients affected by COPD. However, the adaptive molecular mechanisms occurring in these patients after the exposure to the hypoxic stimulus triggered by physical exercise have currently not been described in populations living at high altitude.

METHODS

The clinical trial we are presenting here consists of a quasi-experimental design with longitudinal analysis of repeated measures, with intra- and inter-group comparisons, measuring primary and secondary variables in 4 temporal points. Participants will be people with a diagnosis of COPD residing at high altitudes (> 2600 m), without oncological, renal, cardiac, or musculoskeletal comorbidities with a low level of physical activity. The intervention will be an 8-week program of physical exercise of resistance and muscular strength (8-WVP) which will be carried out at home. Primary outcome variables will be the expression of HIF-1α, VEGF, and EPO. As secondary outcome variables, we will consider lung function (measured by spirometry), physical performance (measured by ergospirometry and dynamometry), and hematological parameters.

DISCUSSION

The results obtained after the clinical trial proposed here will promote knowledge on the expression of signaling proteins as an adaptive response to hypoxia in people with COPD living at high altitude, which will be relevant because there are not data on this population group. The knowledge generated from the application of this protocol will increase the pathophysiological understanding of the disease and future medical and therapeutic decision-making based on physical exercise prescription. TRIAL REGISTRATION {2A}: NCT04955977 [ClinicalTrials.gov]-NCT04955977 [WHO ICRTP]. First Posted: July 9, 2021.

Association of MMP7 T > C Gene Variant (rs10502001) and Expression in Chronic Obstructive Pulmonary Disease

Patients with chronic obstructive pulmonary disease (COPD) have obstructed airflow through their lungs. Single nucleotide polymorphisms in matrix metalloproteinases (MMPs) genes and the risk of COPD have been the subject of numerous studies, with conflicting results. This investigation was conducted to determine whether the MMP7 (T>C) gene variant (rs10502001) was associated with an increased risk of COPD. A case-control study was conducted with 360 subjects (180 healthy controls and 180 COPD cases). The polymerase chain reaction (PCR)-restriction fragment length polymorphism method was used to genotype the SNP rs1050200. mRNA expression of MMP7 was performed using RT-PCR. The genotypic/allelic frequencies and carriage rates of rs10502001 (T>C) polymorphism were evaluated in 180 each of healthy controls and COPD cases. Cases have higher TC/CC genotype frequencies than controls. The "CC" genotype was found to be significantly associated with increased COPD risk (p = 0.016). The "C" allele frequency was higher in cases than in controls and showed significant association with COPD (p = 0.005). The carriage rate frequencies of T(-) and C(+) were significantly higher in cases than in controls (p = 0.031 and 0.047, respectively). MMP7 expression was significantly upregulated (p = 0.001) in COPD cases as compared with the controls. In addition, comparisons of MMP7 expression between the COPD cases with different genotypes showed that the "CC" genotype cases had significantly higher expression than those with "TT" genotype. The present findings showed statistically significant correlation of MMP7 (T>C) polymorphism and expression with COPD. Therefore, MMP7 responsible for degradation of elastin has been strongly linked to the progression of COPD.

The Role of Sphingolipids in Regulating Vascular Permeability in Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a disease that causes scarring and fibrotic transformation of the lung parenchyma, resulting in the progressive loss of respiratory function and, often, death. Current treatments that target profibrotic factors can slow the rate of progression but are unable to ultimately stop it. In the past decade, many studies have shown that increased vascular permeability may be both a predictive and perpetuating factor in fibrogenesis. Consequently, there is a search for therapeutic targets to try and modulate vascular permeability in fibrotic lungs. One such class of targets that show great promise is sphingolipids. Sphingolipids are common in cell membranes and are increasingly recognized as critical to many cell signaling pathways, including those that affect the integrity of the vascular endothelial barrier. In this focused review we look at sphingolipids, particularly the sphingosine-1-phosphate (S1P) axis and its effects on vascular permeability, and how those effects may affect the pathogenesis of IPF. We further examine existing S1P modulators and their potential efficacy as therapeutics for IPF.

Regulatory B cells protect against chronic hypoxia-induced pulmonary hypertension by modulating the Tfh/Tfr immune balance

Hypoxia-induced pulmonary hypertension (HPH) is a progressive and lethal disease characterized by the uncontrolled proliferation of pulmonary artery smooth muscle cells (PASMCs) and obstructive vascular remodelling. Previous research demonstrated that Breg cells were involved in the pathogenesis of pulmonary hypertension. This work aimed to evaluate the regulatory function of Breg cells in HPH. HPH mice model were established and induced by exposing to chronic hypoxia for 21 days. Mice with HPH were treated with anti-CD22 or adoptive transferred of Breg cells. The coculture systems of Breg cells with CD4⁺ T cells and Breg cells with PASMCs in vitro were constructed. Lung pathology was evaluated by HE staining and immunofluorescence staining. The frequencies of Breg cells, Tfh cells and Tfr cells were analysed by flow cytometry. Serum IL-21 and IL-10 levels were determined by ELISA. Protein levels of Blimp-1, Bcl-6 and CTLA-4 were determined by western blot and RT-PCR. Proliferation rate of PASMCs was measured by EdU. Compared to the control group, mean PAP, RV/(LV + S) ratio, WA% and WT% were significantly increased in the model group. Anti-CD22 exacerbated abnormal hemodynamics, pulmonary vascular remodelling and right ventricle hypertrophy in HPH, which ameliorated by adoptive transfer of Breg cells into HPH mice. The proportion of Breg cells on day 7 induced by chronic hypoxia was significantly higher than control group, which significantly decreased on day 14 and day 21. The percentage of Tfh cells was significantly increased, while percentage of Tfr cells was significantly decreased in HPH than those of control group. Anti-CD22 treatment increased the percentage of Tfh cells and decreased the percentage of Tfr cells in HPH mice. However, Breg cells restrained the Tfh cells differentiation and expanded Tfr cells differentiation in vivo and in vitro. Additionally, Breg cells inhibited the proliferation of PASMCs under hypoxic condition in vitro. Collectively, these findings suggested that Breg cells may be a new therapeutic target for modulating the Tfh/Tfr immune balance in HPH.

Small extracellular vesicles derived from human adipose-derived stem cells regulate energetic metabolism through the activation of YAP/TAZ pathway facilitating angiogenesis

Recent studies have found small extracellular vesicles (sEVs) that are secreted from human adipose tissue-derived stem cells (hADSCs-sEVs) and contribute to angiogenesis. Glycolysis, the primary energetic pathway of vascular endothelial cells, plays a key role in the process of angiogenesis. However, hADSCs-sEVs' effects on energy metabolism within endothelial cells remain unclear. In our study, we found that hADSCs-sEVs restored glycolytic metabolism suppressed by 3-(pyridinyl)-1-(4-pyridinyl)-2-propen-1-one(3PO), a unique glycolytic inhibitor increasing the extracellular acidification rate (ECAR), oxygen consumption rate (OCR), glycolytic gene expression as well as pyruvate, lactate, and ATP production in HUVEC cells. In contrast, hADSCs-sEVs decreased PDH-E1α expression and acetyl-CoA production. The above results indicate that hADSCs-sEVs promote HUVEC angiogenesis via enhancing glycolysis and suppressing mitochondrial oxidative phosphorylation. Furthermore, we found that the YAP/TAZ pathway may play a key role in the effects hADSCs-sEVs have on HUVECs, thus, providing a promising approach for pro-angiogenesis-related regeneration.

Exosomal circ-1199 derived from EPCs exposed to oscillating shear stress acts as a sponge of let-7g-5p to promote endothelial-mesenchymal transition of EPCs by increasing HMGA2 expression

AIMS

Our previous study showed that oscillatory shear stress (OSS) induces endothelial progenitor cells (EPCs) to undergo endothelial to mesenchymal transition (EndoMT), which may contribute to the onset and progression of atherosclerosis (AS). However, the underlying mechanisms have not been elucidated. A recent study showed that exosomes (Exos) released from EPCs played a key role in various cardiovascular diseases. The purpose of this study was to identify the role and mechanism of Exos released by EPCs exposed to OSS in EPC EndoMT.

MAIN METHODS

EPCs derived from the human umbilical cord blood were cultured and characterized. The Flexcell flow STR-4000 parallel plate flow chamber system was employed to apply OSS (±3.5 dyne/cm², 1 Hz) to EPCs for 12 h. Then, Exos were extracted from the cellular supernatant (Static-Exos) or perfusate (OSS-Exos) by exoEasy Maxi Kit. Afterward, cellular intervention, angiogenesis assays, high-throughput sequencing and online database predictions were used to identify the role and mechanism of OSS-Exos in EPC EndoMT.

KEY FINDINGS

OSS-Exos inhibited angiogenesis, promoted the proliferation of EPCs both in vivo and in vitro, and induced EPC EndoMT. In addition, the expression of circ-1199 in OSS-Exos was higher than that in Static-Exos. Moreover, circ-1199 induced EPC EndoMT. The dual-luciferase reporter gene assay showed that let-7g-5p was the direct target of circ-1199. Furthermore, OSS-Exos upregulated the expression of circ-1199 and then downregulated let-7g-5p, upregulating HMGA2, which activated p-Smad3/Smad3 and Snail.

SIGNIFICANCE

OSS-Exos played an important role in the EndoMT of EPCs, which was mediated by the circ-1199/let-7g-5p/HMGA2 signaling pathway. These studies would have a high probability of revealing the mechanism of EPC EndoMT.

Analysis of pathogenesis and drug treatment of chronic obstructive pulmonary disease complicated with cardiovascular disease

Chronic obstructive pulmonary disease (COPD) is a disease characterized by persistent airflow limitation, and is associated with abnormal inflammatory responses in the lungs to cigarette smoke and toxic and harmful gases. Due to the existence of common risk factors, COPD is prone to multiple complications, among which cardiovascular disease (CVD) is the most common. It is currently established that cardiovascular comorbidities increase the risk of exacerbations and mortality from COPD. COPD is also an independent risk factor for CVD, and its specific mechanism is still unclear, which may be related to chronic systemic inflammation, oxidative stress, and vascular dysfunction. There is evidence that chronic inflammation of the airways can lead to destruction of the lung parenchyma and decreased lung function. Inflammatory cells in the airways also generate reactive oxygen species in the lungs, and reactive oxygen species further promote lung inflammation through signal transduction and other pathways. Inflammatory mediators circulate from the lungs to the whole body, causing intravascular dysfunction, promoting the formation and rupture of atherosclerotic plaques, and ultimately leading to the occurrence and development of CVD. This article reviews the pathophysiological mechanisms of COPD complicated by CVD and the effects of common cardiovascular drugs on COPD.

Medication use by US patients with pulmonary hypertension associated with chronic obstructive pulmonary disease: a retrospective study of administrative data

BACKGROUND

Pulmonary hypertension (PH) is a serious complication of chronic obstructive pulmonary disease (COPD). While clinical guidelines recommend specific drug therapies for pulmonary arterial hypertension (PAH), these drug therapies are not recommended for PH due to lung disease.

METHODS

This was a retrospective cohort study using the Optum® Clinformatics® Data Mart from January 2009-September 2019. An algorithm was designed to identify adults with ≥ 2 ICD-9-CM or ICD-10-CM diagnosis codes for PH and with ≥ 2 diagnosis codes for COPD. Sensitivity analyses were conducted among subgroups of patients with evidence of a right heart catheterization (RHC) or pulmonary function test (PFT). Patient characteristics, medications used, and durations of use of PAH and COPD medications were analyzed.

RESULTS

A total of 25,975 patients met the study inclusion criteria. Their mean age was 73.5 (SD 10.0) years and 63.8% were female. Medications targeting PAH were prescribed to 643 (2.5%) patients, most frequently a phosphodiesterase-5 inhibitor (2.1%) or an endothelin receptor antagonist (0.75%). Medications for COPD were prescribed to 17,765 (68.4%) patients, most frequently an inhaled corticosteroid (57.4%) or short-acting beta agonist (50.4%). The median durations of use ranged from 4.9 to 12.8 months for PAH medications, and from 0.4 to 5.9 months for COPD medications. Of the subgroup of patients with RHC (N = 2325), 257 (11.1%) were prescribed a PAH medication and 1670 (71.8%) used a COPD medication. Of the subgroup with a PFT (N = 2995), 58 (1.9%) were prescribed a PAH medication and 2100 (70.1%) a COPD medication.

CONCLUSIONS

Patients with PH associated with COPD were identified in a US administrative claims database. Very few of these patients received any of the medications recommended for PAH, and only about two thirds received medications for COPD.

Vasopressin: a possible link between hypoxia and hypertension

Cardiovascular and respiratory diseases are frequently associated with transient and prolonged hypoxia, whereas hypoxia exerts pro-hypertensive effects, through stimulation of the sympathetic system and release of pressor endocrine factors. This review is focused on the role of arginine vasopressin (AVP) in dysregulation of the cardiovascular system during hypoxia associated with cardiovascular disorders. AVP is synthesized mainly in the neuroendocrine neurons of the hypothalamic paraventricular nucleus (PVN) and supraoptic nucleus (SON), which send axons to the posterior pituitary and various regions of the central nervous system (CNS). Vasopressinergic neurons are innervated by multiple neuronal projections releasing several neurotransmitters and other regulatory molecules. AVP interacts with V1a, V1b and V2 receptors that are present in the brain and peripheral organs, including the heart, vessels, lungs, and kidneys. Release of vasopressin is intensified during hypernatremia, hypovolemia, inflammation, stress, pain, and hypoxia which frequently occur in cardiovascular patients, and blood AVP concentration is markedly elevated in cardiovascular diseases associated with hypoxemia. There is evidence that hypoxia stimulates AVP release through stimulation of chemoreceptors. It is suggested that acting in the carotid bodies, AVP may fine-tune respiratory and hemodynamic responses to hypoxia and that this effect is intensified in hypertension. There is also evidence that during hypoxia, augmentation of pro-hypertensive effects of vasopressin may result from inappropriate interaction of this hormone with other compounds regulating the cardiovascular system (catecholamines, angiotensins, natriuretic peptides, steroids, nitric oxide). In conclusion, current literature indicates that abnormal mutual interactions between hypoxia and vasopressin may significantly contribute to pathogenesis of hypertension.

Resistin as a Systemic Inflammation-Related Biomarker for Sarcopenia in Patients With Chronic Obstructive Pulmonary Disease

Background

Sarcopenia is common in patients with chronic obstructive pulmonary disease (COPD) and is mainly caused by systemic inflammation. Resistin acts as a proinflammatory cytokine and is involved in the activation of multiple inflammatory signaling pathways. The aim of this study was to determine the relationship between resistin levels and systemic inflammation and to assess the clinical value of circulating resistin for sarcopenia in patients with COPD.

Methods

In this prospective observational study, we enrolled 235 patients with COPD who were divided into development and validation sets. The definition of sarcopenia followed the guidelines from the Asian Working Group for Sarcopenia. Serum concentrations of resistin and TNF-α were measured using an enzyme-linked immunosorbent assay (ELISA).

Results

In this study, higher serum resistin levels were significantly associated with lower skeletal muscle mass and muscular strength. The serum resistin levels in patients with sarcopenia were significantly higher than those in patients without sarcopenia. The serum resistin level had positive correlations with the serum TNF-α level (r = 0.250, p = 0.007). The predictive efficacy of the serum resistin level (AUC: 0.828) for sarcopenia was superior to that of the serum TNF-α level (AUC: 0.621). The cutoff point (7.138 ng/ml) for the serum resistin level was validated in the validation set (AUC: 0.818).

Conclusions

Serum resistin levels were associated with systemic inflammation and can be used accurately and easily to predict sarcopenia in patients with COPD.

Cigarette smoke extract stimulates human pulmonary artery smooth muscle cell proliferation: Role of inflammation and oxidative stress

Objectives

Cigarette smoke may play a direct role in proliferation of human pulmonary artery smooth muscle cells (HPASMCs). However, the mechanism involved and the effect of interventions remain unclear. We aimed to evaluate the effect of cigarette smoke extract (CSE) on HPASMCs, explore the role of inflammation and oxidative stress, and the effects of Tempol and PDTC in this process.

Materials and Methods

HPASMCs were subjected to normal control (NC), CSE, CSE+Tempol (CSE+T), and CSE+PDTC (CSE+P) groups. Proliferation of HPASMCs was measured by CCK-8 and Western blot. TNF-α, IL-6, MDA, and SOD levels were determined by ELISA and commercial kits. Nuclear translocation of NF-κB p65 was evaluated by western blot.

Results

1%, 2.5%, and 5% CSE all promoted proliferation of HPASMCs, and effect of 1% CSE was the most significant, however, 7.5% and 10% CSE inhibited viability of cells (all P<0.05). Compared with the NC group, TNF-α, IL-6, and MDA levels increased, SOD activity decreased (all P<0.05), and NF-κB p65 expression in nuclei increased (P=0.04) in the CSE group. Tempol and PDTC inhibited the proliferation of HPASMCs induced by CSE (all P<0.05). And compared with the CSE group, TNF-α, IL-6, and MDA levels in CSE+T and CSE+P groups decreased, while SOD activity increased (all P<0.05). Tempol reduced the expression of NF-κB p65 in nuclei but did not achieve a significant difference (P=0.08). PDTC inhibited the nuclear translocation of NF-κB p65 (P=0.03).

Conclusion

CSE stimulates HPASMCs proliferation in a certain concentration range. The CSE-induced proliferation of HPASMCs involved excessive inflammatory response and oxidative stress. Tempol and PDTC attenuate these effects of CSE on HPASMCs.

The Potential Important Role of Mitochondrial Rieske Iron-Sulfur Protein as a Novel Therapeutic Target for Pulmonary Hypertension in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide, which is often due to pulmonary hypertension (PH). The underlying molecular mechanisms are poorly understood, and current medications are neither specific nor always effective. In this review, we highlight the recent findings on the roles of altered mitochondrial bioenergetics in PH in COPD. We also discuss the central role of mitochondrial reactive oxygen species (ROS) generation mediated by Rieske iron-sulfur protein (RISP) and review the contributions of RISP-dependent DNA damage and NF-κB-associated inflammatory signaling. Finally, the potential importance of mitochondrial RISP and its associated molecules as novel therapeutic targets for PH in COPD are meticulously discussed.

Cigarette smoke extract mediates cell premature senescence in chronic obstructive pulmonary disease patients by up-regulating USP7 to activate p300-p53/p21 pathway

OBJECTIVES

Tobacco hazard is one of the most severe public health issues in the world. It is believed that smoking is the most important factor leading to chronic obstructive pulmonary disease (COPD). Endothelial progenitor cells (EPCs) originate from the bone marrow and can effectively repair vascular endothelial damage and improve vascular endothelial function. Current studies suggest that EPCs senescence and EPCs depletion exist in smoking-related COPD, but the molecular mechanism remains unclear.

METHODS

Co-immunoprecipitation was used to detect the interaction between USP7 and p300. EPCs from smoking COPD patients were isolated, and the expressions of USP7 and p300 were detected by RT-PCR and Western Blot. Different concentrations of cigarette smoke extract (CSE) and USP7 or p300 inhibitors were used to treat EPCs, then the expression of p53, p53 target genes and aging-related genes were detected. Cell Counting Kit - 8 (CCK8) was used to detect cell proliferation, flow cytometry was used to detect cell cycle distribution, β-galactosidase (β-gal) staining and Lamp1 immunofluorescence was used to detect the proportion of aging cells. COPD mouse models were used to confirm the molecular mechanism.

RESULTS

USP7 and p300 interacted with each other, and USP7 affected the protein stability of p300 by regulating the ubiquitination of p300. There existed high expressions of USP7 and p300 proteins in EPCs of smoking COPD patients and COPD mouse model. CSE promoted the high expressions of USP7 and p300 in EPCs. Further studies showed that CSE mediated the USP7/p300-dependent high expression of p53 and activated the expression of p53 target genes especially p21. Activation of p53 - p21 pathway finally inhibited cell activity, led to cell cycle arrest and premature senescence of EPCs.

CONCLUSION

CSE mediated up-regulation of USP7 and p300 activated p53 - p21 pathway was a molecular mechanism that might lead to COPD.

Identification of Dysregulated Mechanisms and Candidate Gene Markers in Chronic Obstructive Pulmonary Disease

Purpose

This study aimed to identify candidate gene markers that may facilitate chronic obstructive pulmonary disease (COPD) diagnosis and treatment.

Methods

The GSE47460 and GSE151052 datasets were analyzed to identify differentially expressed mRNAs (DEmRs) between COPD patients and controls. DEmRs that were differentially expressed in the same direction in both datasets were analyzed for functional enrichment and for coexpression. Genes from the largest three modules were tested for their ability to diagnose COPD based on the area under the receiver operating characteristic curve (AUC). Genes with AUC > 0.7 in both datasets were used to perform regression based on the "least absolute shrinkage and selection operator" in order to identify feature genes. We also identified differentially expressed miRNAs (DEmiRs) between COPD patients and controls using the GSE38974 dataset, then constructed a regulatory network. We also examined associations between feature genes and immune cell infiltration in COPD, and we identified methylation markers of COPD using the GSE63704 dataset.

Results

A total of 1350 genes differentially regulated in the same direction in the GSE47460 and GSE151052 datasets were found. The genes were significantly enriched in immune-related biological functions. Of 186 modules identified using MEGENA, the largest were C1_ 6, C1_ 3, and C1_ 2. Of the 22 candidate genes screened based on AUC, 11 feature genes emerged from analysis of a subset of GSE47460 data, which we validated using another subset of GSE47460 data as well as the independent GSE151052 dataset. Feature genes correlated significantly with infiltration by immune cells. The feature genes GPC4 and RS1 were predicted to be regulated by miR-374a-3p. We identified 117 candidate methylation markers of COPD, including PRRG4.

Conclusion

The feature genes we identified may be potential diagnostic markers and therapeutic targets in COPD. These findings provide new leads for exploring disease mechanisms and targeted treatments.

LINC00599 influences smoke-related chronic obstructive pulmonary disease and regulates CSE-induced epithelial cell apoptosis and inflammation by targeting miR-212-5p/BASP1 axis

LINC00599 has been reported to be upregulated in response to cigarette smoking. However, the effect and underlying mechanism of LINC00599 in chronic obstructive pulmonary disease (COPD) are still under exploration. In this study, LINC00599 was upregulated in the COPD patients and was of clinical value to distinguish COPD patients. COPD cell models were established using 16HBE cells under cigarette smoke extract (CSE) treatment. LINC00599 levels were elevated in a dose and time-dependent way in response to CSE stimulation. The effect of LINC00599 on CSE-induced 16HBE cells was explored. The results showed that LINC00599 deficiency reversed the CSE-induced inhibition on cell viability and proliferation, and rescued the CSE-induced enhancement on cell 16HBE cell apoptosis and inflammation response. Moreover, LINC00599 bound with miR-212-5p to upregulate the BASP1 (brain abundant membrane attached signal protein 1) expression. MiR-212-5p was expressed at a low level in the tissue samples of COPD patients, and its levels were upregulated in LINC00599 silenced cells. BASP1 was targeted by miR-212-5p and its upregulation was identified in the tissue samples of COPD patients and cell models. BASP1 levels were downregulated after miR-212-5p overexpression or LINC00599 silencing. Moreover, the rescue assays demonstrated that BASP1 overexpression reversed the effect of silenced LINC00599 on 16HBE cells after CSE treatment, which indicated that LINC00599 promoted the COPD development by regulating BASP1 expression. In conclusion, LINC00599 facilitated CSE-induced cell apoptosis and inflammation response, while inhibiting the cell viability and proliferation in COPD progression via modulating miR-212-5p/BASP1 axis.

Endothelial Dysfunction through Oxidatively Generated Epigenetic Mark in Respiratory Viral Infections

The bronchial vascular endothelial network plays important roles in pulmonary pathology during respiratory viral infections, including respiratory syncytial virus (RSV), influenza A(H1N1) and importantly SARS-Cov-2. All of these infections can be severe and even lethal in patients with underlying risk factors.A major obstacle in disease prevention is the lack of appropriate efficacious vaccine(s) due to continuous changes in the encoding capacity of the viral genome, exuberant responsiveness of the host immune system and lack of effective antiviral drugs. Current management of these severe respiratory viral infections is limited to supportive clinical care. The primary cause of morbidity and mortality is respiratory failure, partially due to endothelial pulmonary complications, including edema. The latter is induced by the loss of alveolar epithelium integrity and by pathological changes in the endothelial vascular network that regulates blood flow, blood fluidity, exchange of fluids, electrolytes, various macromolecules and responses to signals triggered by oxygenation, and controls trafficking of leukocyte immune cells. This overview outlines the latest understanding of the implications of pulmonary vascular endothelium involvement in respiratory distress syndrome secondary to viral infections. In addition, the roles of infection-induced cytokines, growth factors, and epigenetic reprogramming in endothelial permeability, as well as emerging treatment options to decrease disease burden, are discussed.

Characteristics of length of stay and cardiovascular pharmacotherapy advice among chronic obstructive pulmonary disease patients

Chronic obstructive pulmonary disease (COPD) increases the global disease burden due to its diverse adverse health effects on the respiratory and cardiovascular systems. This study aimed to elucidate the potential indicators of length of stay (LOS) and pharmacotherapy advice among COPD patients. Thereafter, hospitalized COPD patients with clinical records and respiratory and cardiovascular pharmacotherapy advice were retrospectively collected from a tertiary hospital between April 2017 and September 2020, and the determinants of LOS and cardiovascular pharmacotherapy advice were explored using regression analyses. Overall, 475 patients with COPD were recruited and stratified according to exacerbation and presence of Cor pulmonale (CP). The extended LOS, increased B-type natriuretic peptides (BNP), and a higher percentage of cardiovascular pharmacotherapy advice were observed in COPD with CP regardless of exacerbation, although the percentage of respiratory prescriptions was comparable. The presence of CP indicated a longer LOS (B = 1.850, p < 0.001) for COPD regardless of exacerbation. Meanwhile, elevated BNP levels indicated cardiovascular pharmacotherapy advise for both COPD in exacerbation (OR = 1.003, p = 0.012) and absence of exacerbation (OR = 1.006, p = 0.015). Moreover, advice for trimetazidine use for COPD in exacerbation (OR = 1.005, p = 0.002) has been suggested. Therefore, CP appears to be an important comorbidity resulting in extended LOS for COPD, which is likely to be advised with cardiovascular pharmacotherapy, which might be guided through BNP monitoring.